vino.c

Go to the documentation of this file.

/*
 * Driver for the VINO (Video In No Out) system found in SGI Indys.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License version 2 as published by the Free Software Foundation.
 *
 * Copyright (C) 2004,2005 Mikael Nousiainen <[email protected]>
 *
 * Based on the previous version of the driver for 2.4 kernels by:
 * Copyright (C) 2003 Ladislav Michl <[email protected]>
 *
 * v4l2_device/v4l2_subdev conversion by:
 * Copyright (C) 2009 Hans Verkuil <[email protected]>
 *
 * Note: this conversion is untested! Please contact the linux-media
 * mailinglist if you can test this, together with the test results.
 */

/*
 * TODO:
 * - remove "mark pages reserved-hacks" from memory allocation code
 *   and implement fault()
 * - check decimation, calculating and reporting image size when
 *   using decimation
 * - implement read(), user mode buffers and overlay (?)
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/time.h>
#include <linux/kmod.h>

#include <linux/i2c.h>

#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <linux/mutex.h>

#include <asm/paccess.h>
#include <asm/io.h>
#include <asm/sgi/ip22.h>
#include <asm/sgi/mc.h>

#include "vino.h"
#include "saa7191.h"
#include "indycam.h"

/* Uncomment the following line to get lots and lots of (mostly useless)
 * debug info.
 * Note that the debug output also slows down the driver significantly */
// #define VINO_DEBUG
// #define VINO_DEBUG_INT

#define VINO_MODULE_VERSION "0.0.7"

MODULE_DESCRIPTION("SGI VINO Video4Linux2 driver");
MODULE_VERSION(VINO_MODULE_VERSION);
MODULE_AUTHOR("Mikael Nousiainen <[email protected]>");
MODULE_LICENSE("GPL");

#ifdef VINO_DEBUG
#define dprintk(x...) printk("VINO: " x);
#else
#define dprintk(x...)
#endif

#define VINO_NO_CHANNEL         0
#define VINO_CHANNEL_A          1
#define VINO_CHANNEL_B          2

#define VINO_PAL_WIDTH          768
#define VINO_PAL_HEIGHT         576
#define VINO_NTSC_WIDTH         640
#define VINO_NTSC_HEIGHT        480

#define VINO_MIN_WIDTH          32
#define VINO_MIN_HEIGHT         32

#define VINO_CLIPPING_START_ODD_D1  1
#define VINO_CLIPPING_START_ODD_PAL 15
#define VINO_CLIPPING_START_ODD_NTSC    12

#define VINO_CLIPPING_START_EVEN_D1 2
#define VINO_CLIPPING_START_EVEN_PAL    15
#define VINO_CLIPPING_START_EVEN_NTSC   12

#define VINO_INPUT_CHANNEL_COUNT    3

/* the number is the index for vino_inputs */
#define VINO_INPUT_NONE         -1
#define VINO_INPUT_COMPOSITE        0
#define VINO_INPUT_SVIDEO       1
#define VINO_INPUT_D1           2

#define VINO_PAGE_RATIO         (PAGE_SIZE / VINO_PAGE_SIZE)

#define VINO_FIFO_THRESHOLD_DEFAULT 16

#define VINO_FRAMEBUFFER_SIZE       ((VINO_PAL_WIDTH \
                      * VINO_PAL_HEIGHT * 4 \
                      + 3 * PAGE_SIZE) & ~(PAGE_SIZE - 1))

#define VINO_FRAMEBUFFER_COUNT_MAX  8

#define VINO_FRAMEBUFFER_UNUSED     0
#define VINO_FRAMEBUFFER_IN_USE     1
#define VINO_FRAMEBUFFER_READY      2

#define VINO_QUEUE_ERROR        -1
#define VINO_QUEUE_MAGIC        0x20050125

#define VINO_MEMORY_NONE        0
#define VINO_MEMORY_MMAP        1
#define VINO_MEMORY_USERPTR     2

#define VINO_DUMMY_DESC_COUNT       4
#define VINO_DESC_FETCH_DELAY       5   /* microseconds */

#define VINO_MAX_FRAME_SKIP_COUNT   128

/* the number is the index for vino_data_formats */
#define VINO_DATA_FMT_NONE      -1
#define VINO_DATA_FMT_GREY      0
#define VINO_DATA_FMT_RGB332        1
#define VINO_DATA_FMT_RGB32     2
#define VINO_DATA_FMT_YUV       3

#define VINO_DATA_FMT_COUNT     4

/* the number is the index for vino_data_norms */
#define VINO_DATA_NORM_NONE     -1
#define VINO_DATA_NORM_NTSC     0
#define VINO_DATA_NORM_PAL      1
#define VINO_DATA_NORM_SECAM        2
#define VINO_DATA_NORM_D1       3

#define VINO_DATA_NORM_COUNT        4

/* I2C controller flags */
#define SGI_I2C_FORCE_IDLE      (0 << 0)
#define SGI_I2C_NOT_IDLE        (1 << 0)
#define SGI_I2C_WRITE           (0 << 1)
#define SGI_I2C_READ            (1 << 1)
#define SGI_I2C_RELEASE_BUS     (0 << 2)
#define SGI_I2C_HOLD_BUS        (1 << 2)
#define SGI_I2C_XFER_DONE       (0 << 4)
#define SGI_I2C_XFER_BUSY       (1 << 4)
#define SGI_I2C_ACK         (0 << 5)
#define SGI_I2C_NACK            (1 << 5)
#define SGI_I2C_BUS_OK          (0 << 7)
#define SGI_I2C_BUS_ERR         (1 << 7)

/* Internal data structure definitions */

struct vino_input {
    char *name;
    v4l2_std_id std;
};

struct vino_clipping {
    unsigned int left, right, top, bottom;
};

struct vino_data_format {
    /* the description */
    char *description;
    /* bytes per pixel */
    unsigned int bpp;
    /* V4L2 fourcc code */
    __u32 pixelformat;
    /* V4L2 colorspace (duh!) */
    enum v4l2_colorspace colorspace;
};

struct vino_data_norm {
    char *description;
    unsigned int width, height;
    struct vino_clipping odd;
    struct vino_clipping even;

    v4l2_std_id std;
    unsigned int fps_min, fps_max;
    __u32 framelines;
};

struct vino_descriptor_table {
    /* the number of PAGE_SIZE sized pages in the buffer */
    unsigned int page_count;
    /* virtual (kmalloc'd) pointers to the actual data
     * (in PAGE_SIZE chunks, used with mmap streaming) */
    unsigned long *virtual;

    /* cpu address for the VINO descriptor table
     * (contains DMA addresses, VINO_PAGE_SIZE chunks) */
    unsigned long *dma_cpu;
    /* dma address for the VINO descriptor table
     * (contains DMA addresses, VINO_PAGE_SIZE chunks) */
    dma_addr_t dma;
};

struct vino_framebuffer {
    /* identifier nubmer */
    unsigned int id;
    /* the length of the whole buffer */
    unsigned int size;
    /* the length of actual data in buffer */
    unsigned int data_size;
    /* the data format */
    unsigned int data_format;
    /* the state of buffer data */
    unsigned int state;
    /* is the buffer mapped in user space? */
    unsigned int map_count;
    /* memory offset for mmap() */
    unsigned int offset;
    /* frame counter */
    unsigned int frame_counter;
    /* timestamp (written when image capture finishes) */
    struct timeval timestamp;

    struct vino_descriptor_table desc_table;

    spinlock_t state_lock;
};

struct vino_framebuffer_fifo {
    unsigned int length;

    unsigned int used;
    unsigned int head;
    unsigned int tail;

    unsigned int data[VINO_FRAMEBUFFER_COUNT_MAX];
};

struct vino_framebuffer_queue {
    unsigned int magic;

    /* VINO_MEMORY_NONE, VINO_MEMORY_MMAP or VINO_MEMORY_USERPTR */
    unsigned int type;
    unsigned int length;

    /* data field of in and out contain index numbers for buffer */
    struct vino_framebuffer_fifo in;
    struct vino_framebuffer_fifo out;

    struct vino_framebuffer *buffer[VINO_FRAMEBUFFER_COUNT_MAX];

    spinlock_t queue_lock;
    struct mutex queue_mutex;
    wait_queue_head_t frame_wait_queue;
};

struct vino_interrupt_data {
    struct timeval timestamp;
    unsigned int frame_counter;
    unsigned int skip_count;
    unsigned int skip;
};

struct vino_channel_settings {
    unsigned int channel;

    int input;
    unsigned int data_format;
    unsigned int data_norm;
    struct vino_clipping clipping;
    unsigned int decimation;
    unsigned int line_size;
    unsigned int alpha;
    unsigned int fps;
    unsigned int framert_reg;

    unsigned int fifo_threshold;

    struct vino_framebuffer_queue fb_queue;

    /* number of the current field */
    unsigned int field;

    /* read in progress */
    int reading;
    /* streaming is active */
    int streaming;
    /* the driver is currently processing the queue */
    int capturing;

    struct mutex mutex;
    spinlock_t capture_lock;

    unsigned int users;

    struct vino_interrupt_data int_data;

    /* V4L support */
    struct video_device *vdev;
};

struct vino_settings {
    struct v4l2_device v4l2_dev;
    struct vino_channel_settings a;
    struct vino_channel_settings b;

    /* the channel which owns this client:
     * VINO_NO_CHANNEL, VINO_CHANNEL_A or VINO_CHANNEL_B */
    unsigned int decoder_owner;
    struct v4l2_subdev *decoder;
    unsigned int camera_owner;
    struct v4l2_subdev *camera;

    /* a lock for vino register access */
    spinlock_t vino_lock;
    /* a lock for channel input changes */
    spinlock_t input_lock;

    unsigned long dummy_page;
    struct vino_descriptor_table dummy_desc_table;
};

/* Module parameters */

/*
 * Using vino_pixel_conversion the ABGR32-format pixels supplied
 * by the VINO chip can be converted to more common formats
 * like RGBA32 (or probably RGB24 in the future). This way we
 * can give out data that can be specified correctly with
 * the V4L2-definitions.
 *
 * The pixel format is specified as RGBA32 when no conversion
 * is used.
 *
 * Note that this only affects the 32-bit bit depth.
 *
 * Use non-zero value to enable conversion.
 */
static int vino_pixel_conversion;

module_param_named(pixelconv, vino_pixel_conversion, int, 0);

MODULE_PARM_DESC(pixelconv,
         "enable pixel conversion (non-zero value enables)");

/* Internal data structures */

static struct sgi_vino *vino;

static struct vino_settings *vino_drvdata;

#define camera_call(o, f, args...) \
    v4l2_subdev_call(vino_drvdata->camera, o, f, ##args)
#define decoder_call(o, f, args...) \
    v4l2_subdev_call(vino_drvdata->decoder, o, f, ##args)

static const char *vino_driver_name = "vino";
static const char *vino_driver_description = "SGI VINO";
static const char *vino_bus_name = "GIO64 bus";
static const char *vino_vdev_name_a = "SGI VINO Channel A";
static const char *vino_vdev_name_b = "SGI VINO Channel B";

static void vino_capture_tasklet(unsigned long channel);

DECLARE_TASKLET(vino_tasklet_a, vino_capture_tasklet, VINO_CHANNEL_A);
DECLARE_TASKLET(vino_tasklet_b, vino_capture_tasklet, VINO_CHANNEL_B);

static const struct vino_input vino_inputs[] = {
    {
        .name       = "Composite",
        .std        = V4L2_STD_NTSC | V4L2_STD_PAL
        | V4L2_STD_SECAM,
    }, {
        .name       = "S-Video",
        .std        = V4L2_STD_NTSC | V4L2_STD_PAL
        | V4L2_STD_SECAM,
    }, {
        .name       = "D1/IndyCam",
        .std        = V4L2_STD_NTSC,
    }
};

static const struct vino_data_format vino_data_formats[] = {
    {
        .description    = "8-bit greyscale",
        .bpp        = 1,
        .pixelformat    = V4L2_PIX_FMT_GREY,
        .colorspace = V4L2_COLORSPACE_SMPTE170M,
    }, {
        .description    = "8-bit dithered RGB 3-3-2",
        .bpp        = 1,
        .pixelformat    = V4L2_PIX_FMT_RGB332,
        .colorspace = V4L2_COLORSPACE_SRGB,
    }, {
        .description    = "32-bit RGB",
        .bpp        = 4,
        .pixelformat    = V4L2_PIX_FMT_RGB32,
        .colorspace = V4L2_COLORSPACE_SRGB,
    }, {
        .description    = "YUV 4:2:2",
        .bpp        = 2,
        .pixelformat    = V4L2_PIX_FMT_YUYV, // XXX: swapped?
        .colorspace = V4L2_COLORSPACE_SMPTE170M,
    }
};

static const struct vino_data_norm vino_data_norms[] = {
    {
        .description    = "NTSC",
        .std        = V4L2_STD_NTSC,
        .fps_min    = 6,
        .fps_max    = 30,
        .framelines = 525,
        .width      = VINO_NTSC_WIDTH,
        .height     = VINO_NTSC_HEIGHT,
        .odd        = {
            .top    = VINO_CLIPPING_START_ODD_NTSC,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_ODD_NTSC
            + VINO_NTSC_HEIGHT / 2 - 1,
            .right  = VINO_NTSC_WIDTH,
        },
        .even       = {
            .top    = VINO_CLIPPING_START_EVEN_NTSC,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_EVEN_NTSC
            + VINO_NTSC_HEIGHT / 2 - 1,
            .right  = VINO_NTSC_WIDTH,
        },
    }, {
        .description    = "PAL",
        .std        = V4L2_STD_PAL,
        .fps_min    = 5,
        .fps_max    = 25,
        .framelines = 625,
        .width      = VINO_PAL_WIDTH,
        .height     = VINO_PAL_HEIGHT,
        .odd        = {
            .top    = VINO_CLIPPING_START_ODD_PAL,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_ODD_PAL
            + VINO_PAL_HEIGHT / 2 - 1,
            .right  = VINO_PAL_WIDTH,
        },
        .even       = {
            .top    = VINO_CLIPPING_START_EVEN_PAL,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_EVEN_PAL
            + VINO_PAL_HEIGHT / 2 - 1,
            .right  = VINO_PAL_WIDTH,
        },
    }, {
        .description    = "SECAM",
        .std        = V4L2_STD_SECAM,
        .fps_min    = 5,
        .fps_max    = 25,
        .framelines = 625,
        .width      = VINO_PAL_WIDTH,
        .height     = VINO_PAL_HEIGHT,
        .odd        = {
            .top    = VINO_CLIPPING_START_ODD_PAL,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_ODD_PAL
            + VINO_PAL_HEIGHT / 2 - 1,
            .right  = VINO_PAL_WIDTH,
        },
        .even       = {
            .top    = VINO_CLIPPING_START_EVEN_PAL,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_EVEN_PAL
            + VINO_PAL_HEIGHT / 2 - 1,
            .right  = VINO_PAL_WIDTH,
        },
    }, {
        .description    = "NTSC/D1",
        .std        = V4L2_STD_NTSC,
        .fps_min    = 6,
        .fps_max    = 30,
        .framelines = 525,
        .width      = VINO_NTSC_WIDTH,
        .height     = VINO_NTSC_HEIGHT,
        .odd        = {
            .top    = VINO_CLIPPING_START_ODD_D1,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_ODD_D1
            + VINO_NTSC_HEIGHT / 2 - 1,
            .right  = VINO_NTSC_WIDTH,
        },
        .even       = {
            .top    = VINO_CLIPPING_START_EVEN_D1,
            .left   = 0,
            .bottom = VINO_CLIPPING_START_EVEN_D1
            + VINO_NTSC_HEIGHT / 2 - 1,
            .right  = VINO_NTSC_WIDTH,
        },
    }
};

#define VINO_INDYCAM_V4L2_CONTROL_COUNT     9

struct v4l2_queryctrl vino_indycam_v4l2_controls[] = {
    {
        .id = V4L2_CID_AUTOGAIN,
        .type = V4L2_CTRL_TYPE_BOOLEAN,
        .name = "Automatic Gain Control",
        .minimum = 0,
        .maximum = 1,
        .step = 1,
        .default_value = INDYCAM_AGC_DEFAULT,
    }, {
        .id = V4L2_CID_AUTO_WHITE_BALANCE,
        .type = V4L2_CTRL_TYPE_BOOLEAN,
        .name = "Automatic White Balance",
        .minimum = 0,
        .maximum = 1,
        .step = 1,
        .default_value = INDYCAM_AWB_DEFAULT,
    }, {
        .id = V4L2_CID_GAIN,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Gain",
        .minimum = INDYCAM_GAIN_MIN,
        .maximum = INDYCAM_GAIN_MAX,
        .step = 1,
        .default_value = INDYCAM_GAIN_DEFAULT,
    }, {
        .id = INDYCAM_CONTROL_RED_SATURATION,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Red Saturation",
        .minimum = INDYCAM_RED_SATURATION_MIN,
        .maximum = INDYCAM_RED_SATURATION_MAX,
        .step = 1,
        .default_value = INDYCAM_RED_SATURATION_DEFAULT,
    }, {
        .id = INDYCAM_CONTROL_BLUE_SATURATION,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Blue Saturation",
        .minimum = INDYCAM_BLUE_SATURATION_MIN,
        .maximum = INDYCAM_BLUE_SATURATION_MAX,
        .step = 1,
        .default_value = INDYCAM_BLUE_SATURATION_DEFAULT,
    }, {
        .id = V4L2_CID_RED_BALANCE,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Red Balance",
        .minimum = INDYCAM_RED_BALANCE_MIN,
        .maximum = INDYCAM_RED_BALANCE_MAX,
        .step = 1,
        .default_value = INDYCAM_RED_BALANCE_DEFAULT,
    }, {
        .id = V4L2_CID_BLUE_BALANCE,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Blue Balance",
        .minimum = INDYCAM_BLUE_BALANCE_MIN,
        .maximum = INDYCAM_BLUE_BALANCE_MAX,
        .step = 1,
        .default_value = INDYCAM_BLUE_BALANCE_DEFAULT,
    }, {
        .id = V4L2_CID_EXPOSURE,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Shutter Control",
        .minimum = INDYCAM_SHUTTER_MIN,
        .maximum = INDYCAM_SHUTTER_MAX,
        .step = 1,
        .default_value = INDYCAM_SHUTTER_DEFAULT,
    }, {
        .id = V4L2_CID_GAMMA,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Gamma",
        .minimum = INDYCAM_GAMMA_MIN,
        .maximum = INDYCAM_GAMMA_MAX,
        .step = 1,
        .default_value = INDYCAM_GAMMA_DEFAULT,
    }
};

#define VINO_SAA7191_V4L2_CONTROL_COUNT     9

struct v4l2_queryctrl vino_saa7191_v4l2_controls[] = {
    {
        .id = V4L2_CID_HUE,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Hue",
        .minimum = SAA7191_HUE_MIN,
        .maximum = SAA7191_HUE_MAX,
        .step = 1,
        .default_value = SAA7191_HUE_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_BANDPASS,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Luminance Bandpass",
        .minimum = SAA7191_BANDPASS_MIN,
        .maximum = SAA7191_BANDPASS_MAX,
        .step = 1,
        .default_value = SAA7191_BANDPASS_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_BANDPASS_WEIGHT,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Luminance Bandpass Weight",
        .minimum = SAA7191_BANDPASS_WEIGHT_MIN,
        .maximum = SAA7191_BANDPASS_WEIGHT_MAX,
        .step = 1,
        .default_value = SAA7191_BANDPASS_WEIGHT_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_CORING,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "HF Luminance Coring",
        .minimum = SAA7191_CORING_MIN,
        .maximum = SAA7191_CORING_MAX,
        .step = 1,
        .default_value = SAA7191_CORING_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_FORCE_COLOUR,
        .type = V4L2_CTRL_TYPE_BOOLEAN,
        .name = "Force Colour",
        .minimum = SAA7191_FORCE_COLOUR_MIN,
        .maximum = SAA7191_FORCE_COLOUR_MAX,
        .step = 1,
        .default_value = SAA7191_FORCE_COLOUR_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_CHROMA_GAIN,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Chrominance Gain Control",
        .minimum = SAA7191_CHROMA_GAIN_MIN,
        .maximum = SAA7191_CHROMA_GAIN_MAX,
        .step = 1,
        .default_value = SAA7191_CHROMA_GAIN_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_VTRC,
        .type = V4L2_CTRL_TYPE_BOOLEAN,
        .name = "VTR Time Constant",
        .minimum = SAA7191_VTRC_MIN,
        .maximum = SAA7191_VTRC_MAX,
        .step = 1,
        .default_value = SAA7191_VTRC_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_LUMA_DELAY,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Luminance Delay Compensation",
        .minimum = SAA7191_LUMA_DELAY_MIN,
        .maximum = SAA7191_LUMA_DELAY_MAX,
        .step = 1,
        .default_value = SAA7191_LUMA_DELAY_DEFAULT,
    }, {
        .id = SAA7191_CONTROL_VNR,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Vertical Noise Reduction",
        .minimum = SAA7191_VNR_MIN,
        .maximum = SAA7191_VNR_MAX,
        .step = 1,
        .default_value = SAA7191_VNR_DEFAULT,
    }
};

/* VINO framebuffer/DMA descriptor management */

static void vino_free_buffer_with_count(struct vino_framebuffer *fb,
                           unsigned int count)
{
    unsigned int i;

    dprintk("vino_free_buffer_with_count(): count = %d\n", count);

    for (i = 0; i < count; i++) {
        ClearPageReserved(virt_to_page((void *)fb->desc_table.virtual[i]));
        dma_unmap_single(NULL,
                 fb->desc_table.dma_cpu[VINO_PAGE_RATIO * i],
                 PAGE_SIZE, DMA_FROM_DEVICE);
        free_page(fb->desc_table.virtual[i]);
    }

    dma_free_coherent(NULL,
              VINO_PAGE_RATIO * (fb->desc_table.page_count + 4) *
              sizeof(dma_addr_t), (void *)fb->desc_table.dma_cpu,
              fb->desc_table.dma);
    kfree(fb->desc_table.virtual);

    memset(fb, 0, sizeof(struct vino_framebuffer));
}

static void vino_free_buffer(struct vino_framebuffer *fb)
{
    vino_free_buffer_with_count(fb, fb->desc_table.page_count);
}

static int vino_allocate_buffer(struct vino_framebuffer *fb,
                unsigned int size)
{
    unsigned int count, i, j;
    int ret = 0;

    dprintk("vino_allocate_buffer():\n");

    if (size < 1)
        return -EINVAL;

    memset(fb, 0, sizeof(struct vino_framebuffer));

    count = ((size / PAGE_SIZE) + 4) & ~3;

    dprintk("vino_allocate_buffer(): size = %d, count = %d\n",
        size, count);

    /* allocate memory for table with virtual (page) addresses */
    fb->desc_table.virtual =
        kmalloc(count * sizeof(unsigned long), GFP_KERNEL);
    if (!fb->desc_table.virtual)
        return -ENOMEM;

    /* allocate memory for table with dma addresses
     * (has space for four extra descriptors) */
    fb->desc_table.dma_cpu =
        dma_alloc_coherent(NULL, VINO_PAGE_RATIO * (count + 4) *
                   sizeof(dma_addr_t), &fb->desc_table.dma,
                   GFP_KERNEL | GFP_DMA);
    if (!fb->desc_table.dma_cpu) {
        ret = -ENOMEM;
        goto out_free_virtual;
    }

    /* allocate pages for the buffer and acquire the according
     * dma addresses */
    for (i = 0; i < count; i++) {
        dma_addr_t dma_data_addr;

        fb->desc_table.virtual[i] =
            get_zeroed_page(GFP_KERNEL | GFP_DMA);
        if (!fb->desc_table.virtual[i]) {
            ret = -ENOBUFS;
            break;
        }

        dma_data_addr =
            dma_map_single(NULL,
                       (void *)fb->desc_table.virtual[i],
                       PAGE_SIZE, DMA_FROM_DEVICE);

        for (j = 0; j < VINO_PAGE_RATIO; j++) {
            fb->desc_table.dma_cpu[VINO_PAGE_RATIO * i + j] =
                dma_data_addr + VINO_PAGE_SIZE * j;
        }

        SetPageReserved(virt_to_page((void *)fb->desc_table.virtual[i]));
    }

    /* page_count needs to be set anyway, because the descriptor table has
     * been allocated according to this number */
    fb->desc_table.page_count = count;

    if (ret) {
        /* the descriptor with index i doesn't contain
         * a valid address yet */
        vino_free_buffer_with_count(fb, i);
        return ret;
    }

    //fb->size = size;
    fb->size = count * PAGE_SIZE;
    fb->data_format = VINO_DATA_FMT_NONE;

    /* set the dma stop-bit for the last (count+1)th descriptor */
    fb->desc_table.dma_cpu[VINO_PAGE_RATIO * count] = VINO_DESC_STOP;
    return 0;

 out_free_virtual:
    kfree(fb->desc_table.virtual);
    return ret;
}

#if 0
/* user buffers not fully implemented yet */
static int vino_prepare_user_buffer(struct vino_framebuffer *fb,
                     void *user,
                     unsigned int size)
{
    unsigned int count, i, j;
    int ret = 0;

    dprintk("vino_prepare_user_buffer():\n");

    if (size < 1)
        return -EINVAL;

    memset(fb, 0, sizeof(struct vino_framebuffer));

    count = ((size / PAGE_SIZE)) & ~3;

    dprintk("vino_prepare_user_buffer(): size = %d, count = %d\n",
        size, count);

    /* allocate memory for table with virtual (page) addresses */
    fb->desc_table.virtual = (unsigned long *)
        kmalloc(count * sizeof(unsigned long), GFP_KERNEL);
    if (!fb->desc_table.virtual)
        return -ENOMEM;

    /* allocate memory for table with dma addresses
     * (has space for four extra descriptors) */
    fb->desc_table.dma_cpu =
        dma_alloc_coherent(NULL, VINO_PAGE_RATIO * (count + 4) *
                   sizeof(dma_addr_t), &fb->desc_table.dma,
                   GFP_KERNEL | GFP_DMA);
    if (!fb->desc_table.dma_cpu) {
        ret = -ENOMEM;
        goto out_free_virtual;
    }

    /* allocate pages for the buffer and acquire the according
     * dma addresses */
    for (i = 0; i < count; i++) {
        dma_addr_t dma_data_addr;

        fb->desc_table.virtual[i] =
            get_zeroed_page(GFP_KERNEL | GFP_DMA);
        if (!fb->desc_table.virtual[i]) {
            ret = -ENOBUFS;
            break;
        }

        dma_data_addr =
            dma_map_single(NULL,
                       (void *)fb->desc_table.virtual[i],
                       PAGE_SIZE, DMA_FROM_DEVICE);

        for (j = 0; j < VINO_PAGE_RATIO; j++) {
            fb->desc_table.dma_cpu[VINO_PAGE_RATIO * i + j] =
                dma_data_addr + VINO_PAGE_SIZE * j;
        }

        SetPageReserved(virt_to_page((void *)fb->desc_table.virtual[i]));
    }

    /* page_count needs to be set anyway, because the descriptor table has
     * been allocated according to this number */
    fb->desc_table.page_count = count;

    if (ret) {
        /* the descriptor with index i doesn't contain
         * a valid address yet */
        vino_free_buffer_with_count(fb, i);
        return ret;
    }

    //fb->size = size;
    fb->size = count * PAGE_SIZE;

    /* set the dma stop-bit for the last (count+1)th descriptor */
    fb->desc_table.dma_cpu[VINO_PAGE_RATIO * count] = VINO_DESC_STOP;
    return 0;

 out_free_virtual:
    kfree(fb->desc_table.virtual);
    return ret;
}
#endif

static void vino_sync_buffer(struct vino_framebuffer *fb)
{
    int i;

    dprintk("vino_sync_buffer():\n");

    for (i = 0; i < fb->desc_table.page_count; i++)
        dma_sync_single_for_cpu(NULL,
                    fb->desc_table.dma_cpu[VINO_PAGE_RATIO * i],
                    PAGE_SIZE, DMA_FROM_DEVICE);
}

/* Framebuffer fifo functions (need to be locked externally) */

static inline void vino_fifo_init(struct vino_framebuffer_fifo *f,
               unsigned int length)
{
    f->length = 0;
    f->used = 0;
    f->head = 0;
    f->tail = 0;

    if (length > VINO_FRAMEBUFFER_COUNT_MAX)
        length = VINO_FRAMEBUFFER_COUNT_MAX;

    f->length = length;
}

/* returns true/false */
static inline int vino_fifo_has_id(struct vino_framebuffer_fifo *f,
                   unsigned int id)
{
    unsigned int i;

    for (i = f->head; i == (f->tail - 1); i = (i + 1) % f->length) {
        if (f->data[i] == id)
            return 1;
    }

    return 0;
}

#if 0
/* returns true/false */
static inline int vino_fifo_full(struct vino_framebuffer_fifo *f)
{
    return (f->used == f->length);
}
#endif

static inline unsigned int vino_fifo_get_used(struct vino_framebuffer_fifo *f)
{
    return f->used;
}

static int vino_fifo_enqueue(struct vino_framebuffer_fifo *f, unsigned int id)
{
    if (id >= f->length) {
        return VINO_QUEUE_ERROR;
    }

    if (vino_fifo_has_id(f, id)) {
        return VINO_QUEUE_ERROR;
    }

    if (f->used < f->length) {
        f->data[f->tail] = id;
        f->tail = (f->tail + 1) % f->length;
        f->used++;
    } else {
        return VINO_QUEUE_ERROR;
    }

    return 0;
}

static int vino_fifo_peek(struct vino_framebuffer_fifo *f, unsigned int *id)
{
    if (f->used > 0) {
        *id = f->data[f->head];
    } else {
        return VINO_QUEUE_ERROR;
    }

    return 0;
}

static int vino_fifo_dequeue(struct vino_framebuffer_fifo *f, unsigned int *id)
{
    if (f->used > 0) {
        *id = f->data[f->head];
        f->head = (f->head + 1) % f->length;
        f->used--;
    } else {
        return VINO_QUEUE_ERROR;
    }

    return 0;
}

/* Framebuffer queue functions */

/* execute with queue_lock locked */
static void vino_queue_free_with_count(struct vino_framebuffer_queue *q,
                       unsigned int length)
{
    unsigned int i;

    q->length = 0;
    memset(&q->in, 0, sizeof(struct vino_framebuffer_fifo));
    memset(&q->out, 0, sizeof(struct vino_framebuffer_fifo));
    for (i = 0; i < length; i++) {
        dprintk("vino_queue_free_with_count(): freeing buffer %d\n",
            i);
        vino_free_buffer(q->buffer[i]);
        kfree(q->buffer[i]);
    }

    q->type = VINO_MEMORY_NONE;
    q->magic = 0;
}

static void vino_queue_free(struct vino_framebuffer_queue *q)
{
    dprintk("vino_queue_free():\n");

    if (q->magic != VINO_QUEUE_MAGIC)
        return;
    if (q->type != VINO_MEMORY_MMAP)
        return;

    mutex_lock(&q->queue_mutex);

    vino_queue_free_with_count(q, q->length);

    mutex_unlock(&q->queue_mutex);
}

static int vino_queue_init(struct vino_framebuffer_queue *q,
               unsigned int *length)
{
    unsigned int i;
    int ret = 0;

    dprintk("vino_queue_init(): length = %d\n", *length);

    if (q->magic == VINO_QUEUE_MAGIC) {
        dprintk("vino_queue_init(): queue already initialized!\n");
        return -EINVAL;
    }

    if (q->type != VINO_MEMORY_NONE) {
        dprintk("vino_queue_init(): queue already initialized!\n");
        return -EINVAL;
    }

    if (*length < 1)
        return -EINVAL;

    mutex_lock(&q->queue_mutex);

    if (*length > VINO_FRAMEBUFFER_COUNT_MAX)
        *length = VINO_FRAMEBUFFER_COUNT_MAX;

    q->length = 0;

    for (i = 0; i < *length; i++) {
        dprintk("vino_queue_init(): allocating buffer %d\n", i);
        q->buffer[i] = kmalloc(sizeof(struct vino_framebuffer),
                       GFP_KERNEL);
        if (!q->buffer[i]) {
            dprintk("vino_queue_init(): kmalloc() failed\n");
            ret = -ENOMEM;
            break;
        }

        ret = vino_allocate_buffer(q->buffer[i],
                       VINO_FRAMEBUFFER_SIZE);
        if (ret) {
            kfree(q->buffer[i]);
            dprintk("vino_queue_init(): "
                "vino_allocate_buffer() failed\n");
            break;
        }

        q->buffer[i]->id = i;
        if (i > 0) {
            q->buffer[i]->offset = q->buffer[i - 1]->offset +
                q->buffer[i - 1]->size;
        } else {
            q->buffer[i]->offset = 0;
        }

        spin_lock_init(&q->buffer[i]->state_lock);

        dprintk("vino_queue_init(): buffer = %d, offset = %d, "
            "size = %d\n", i, q->buffer[i]->offset,
            q->buffer[i]->size);
    }

    if (ret) {
        vino_queue_free_with_count(q, i);
        *length = 0;
    } else {
        q->length = *length;
        vino_fifo_init(&q->in, q->length);
        vino_fifo_init(&q->out, q->length);
        q->type = VINO_MEMORY_MMAP;
        q->magic = VINO_QUEUE_MAGIC;
    }

    mutex_unlock(&q->queue_mutex);

    return ret;
}

static struct vino_framebuffer *vino_queue_add(struct
                           vino_framebuffer_queue *q,
                           unsigned int id)
{
    struct vino_framebuffer *ret = NULL;
    unsigned int total;
    unsigned long flags;

    dprintk("vino_queue_add(): id = %d\n", id);

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0)
        goto out;

    if (id >= q->length)
        goto out;

    /* not needed?: if (vino_fifo_full(&q->out)) {
        goto out;
        }*/
    /* check that outgoing queue isn't already full
     * (or that it won't become full) */
    total = vino_fifo_get_used(&q->in) +
        vino_fifo_get_used(&q->out);
    if (total >= q->length)
        goto out;

    if (vino_fifo_enqueue(&q->in, id))
        goto out;

    ret = q->buffer[id];

out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

static struct vino_framebuffer *vino_queue_transfer(struct
                            vino_framebuffer_queue *q)
{
    struct vino_framebuffer *ret = NULL;
    struct vino_framebuffer *fb;
    int id;
    unsigned long flags;

    dprintk("vino_queue_transfer():\n");

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0)
        goto out;

    // now this actually removes an entry from the incoming queue
    if (vino_fifo_dequeue(&q->in, &id)) {
        goto out;
    }

    dprintk("vino_queue_transfer(): id = %d\n", id);
    fb = q->buffer[id];

    // we have already checked that the outgoing queue is not full, but...
    if (vino_fifo_enqueue(&q->out, id)) {
        printk(KERN_ERR "vino_queue_transfer(): "
               "outgoing queue is full, this shouldn't happen!\n");
        goto out;
    }

    ret = fb;
out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

/* returns true/false */
static int vino_queue_incoming_contains(struct vino_framebuffer_queue *q,
                    unsigned int id)
{
    int ret = 0;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0)
        goto out;

    ret = vino_fifo_has_id(&q->in, id);

out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

/* returns true/false */
static int vino_queue_outgoing_contains(struct vino_framebuffer_queue *q,
                    unsigned int id)
{
    int ret = 0;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0)
        goto out;

    ret = vino_fifo_has_id(&q->out, id);

out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

static int vino_queue_get_incoming(struct vino_framebuffer_queue *q,
                   unsigned int *used)
{
    int ret = 0;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return VINO_QUEUE_ERROR;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0) {
        ret = VINO_QUEUE_ERROR;
        goto out;
    }

    *used = vino_fifo_get_used(&q->in);

out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

static int vino_queue_get_outgoing(struct vino_framebuffer_queue *q,
                   unsigned int *used)
{
    int ret = 0;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return VINO_QUEUE_ERROR;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0) {
        ret = VINO_QUEUE_ERROR;
        goto out;
    }

    *used = vino_fifo_get_used(&q->out);

out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

#if 0
static int vino_queue_get_total(struct vino_framebuffer_queue *q,
                unsigned int *total)
{
    int ret = 0;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return VINO_QUEUE_ERROR;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0) {
        ret = VINO_QUEUE_ERROR;
        goto out;
    }

    *total = vino_fifo_get_used(&q->in) +
        vino_fifo_get_used(&q->out);

out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}
#endif

static struct vino_framebuffer *vino_queue_peek(struct
                        vino_framebuffer_queue *q,
                        unsigned int *id)
{
    struct vino_framebuffer *ret = NULL;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0)
        goto out;

    if (vino_fifo_peek(&q->in, id)) {
        goto out;
    }

    ret = q->buffer[*id];
out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

static struct vino_framebuffer *vino_queue_remove(struct
                          vino_framebuffer_queue *q,
                          unsigned int *id)
{
    struct vino_framebuffer *ret = NULL;
    unsigned long flags;
    dprintk("vino_queue_remove():\n");

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0)
        goto out;

    if (vino_fifo_dequeue(&q->out, id)) {
        goto out;
    }

    dprintk("vino_queue_remove(): id = %d\n", *id);
    ret = q->buffer[*id];
out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

static struct
vino_framebuffer *vino_queue_get_buffer(struct vino_framebuffer_queue *q,
                    unsigned int id)
{
    struct vino_framebuffer *ret = NULL;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);

    if (q->length == 0)
        goto out;

    if (id >= q->length)
        goto out;

    ret = q->buffer[id];
 out:
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

static unsigned int vino_queue_get_length(struct vino_framebuffer_queue *q)
{
    unsigned int length = 0;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return length;
    }

    spin_lock_irqsave(&q->queue_lock, flags);
    length = q->length;
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return length;
}

static int vino_queue_has_mapped_buffers(struct vino_framebuffer_queue *q)
{
    unsigned int i;
    int ret = 0;
    unsigned long flags;

    if (q->magic != VINO_QUEUE_MAGIC) {
        return ret;
    }

    spin_lock_irqsave(&q->queue_lock, flags);
    for (i = 0; i < q->length; i++) {
        if (q->buffer[i]->map_count > 0) {
            ret = 1;
            break;
        }
    }
    spin_unlock_irqrestore(&q->queue_lock, flags);

    return ret;
}

/* VINO functions */

/* execute with input_lock locked */
static void vino_update_line_size(struct vino_channel_settings *vcs)
{
    unsigned int w = vcs->clipping.right - vcs->clipping.left;
    unsigned int d = vcs->decimation;
    unsigned int bpp = vino_data_formats[vcs->data_format].bpp;
    unsigned int lsize;

    dprintk("update_line_size(): before: w = %d, d = %d, "
        "line_size = %d\n", w, d, vcs->line_size);

    /* line size must be multiple of 8 bytes */
    lsize = (bpp * (w / d)) & ~7;
    w = (lsize / bpp) * d;

    vcs->clipping.right = vcs->clipping.left + w;
    vcs->line_size = lsize;

    dprintk("update_line_size(): after: w = %d, d = %d, "
        "line_size = %d\n", w, d, vcs->line_size);
}

/* execute with input_lock locked */
static void vino_set_clipping(struct vino_channel_settings *vcs,
                  unsigned int x, unsigned int y,
                  unsigned int w, unsigned int h)
{
    unsigned int maxwidth, maxheight;
    unsigned int d;

    maxwidth = vino_data_norms[vcs->data_norm].width;
    maxheight = vino_data_norms[vcs->data_norm].height;
    d = vcs->decimation;

    y &= ~1;    /* odd/even fields */

    if (x > maxwidth) {
        x = 0;
    }
    if (y > maxheight) {
        y = 0;
    }

    if (((w / d) < VINO_MIN_WIDTH)
        || ((h / d) < VINO_MIN_HEIGHT)) {
        w = VINO_MIN_WIDTH * d;
        h = VINO_MIN_HEIGHT * d;
    }

    if ((x + w) > maxwidth) {
        w = maxwidth - x;
        if ((w / d) < VINO_MIN_WIDTH)
            x = maxwidth - VINO_MIN_WIDTH * d;
    }
    if ((y + h) > maxheight) {
        h = maxheight - y;
        if ((h / d) < VINO_MIN_HEIGHT)
            y = maxheight - VINO_MIN_HEIGHT * d;
    }

    vcs->clipping.left = x;
    vcs->clipping.top = y;
    vcs->clipping.right = x + w;
    vcs->clipping.bottom = y + h;

    vino_update_line_size(vcs);

    dprintk("clipping %d, %d, %d, %d / %d - %d\n",
        vcs->clipping.left, vcs->clipping.top, vcs->clipping.right,
        vcs->clipping.bottom, vcs->decimation, vcs->line_size);
}

/* execute with input_lock locked */
static inline void vino_set_default_clipping(struct vino_channel_settings *vcs)
{
    vino_set_clipping(vcs, 0, 0, vino_data_norms[vcs->data_norm].width,
              vino_data_norms[vcs->data_norm].height);
}

/* execute with input_lock locked */
static void vino_set_scaling(struct vino_channel_settings *vcs,
                 unsigned int w, unsigned int h)
{
    unsigned int x, y, curw, curh, d;

    x = vcs->clipping.left;
    y = vcs->clipping.top;
    curw = vcs->clipping.right - vcs->clipping.left;
    curh = vcs->clipping.bottom - vcs->clipping.top;

    d = max(curw / w, curh / h);

    dprintk("scaling w: %d, h: %d, curw: %d, curh: %d, d: %d\n",
        w, h, curw, curh, d);

    if (d < 1) {
        d = 1;
    } else if (d > 8) {
        d = 8;
    }

    vcs->decimation = d;
    vino_set_clipping(vcs, x, y, w * d, h * d);

    dprintk("scaling %d, %d, %d, %d / %d - %d\n", vcs->clipping.left,
        vcs->clipping.top, vcs->clipping.right, vcs->clipping.bottom,
        vcs->decimation, vcs->line_size);
}

/* execute with input_lock locked */
static inline void vino_set_default_scaling(struct vino_channel_settings *vcs)
{
    vino_set_scaling(vcs, vcs->clipping.right - vcs->clipping.left,
             vcs->clipping.bottom - vcs->clipping.top);
}

/* execute with input_lock locked */
static void vino_set_framerate(struct vino_channel_settings *vcs,
                   unsigned int fps)
{
    unsigned int mask;

    switch (vcs->data_norm) {
    case VINO_DATA_NORM_NTSC:
    case VINO_DATA_NORM_D1:
        fps = (unsigned int)(fps / 6) * 6; // FIXME: round!

        if (fps < vino_data_norms[vcs->data_norm].fps_min)
            fps = vino_data_norms[vcs->data_norm].fps_min;
        if (fps > vino_data_norms[vcs->data_norm].fps_max)
            fps = vino_data_norms[vcs->data_norm].fps_max;

        switch (fps) {
        case 6:
            mask = 0x003;
            break;
        case 12:
            mask = 0x0c3;
            break;
        case 18:
            mask = 0x333;
            break;
        case 24:
            mask = 0x3ff;
            break;
        case 30:
            mask = 0xfff;
            break;
        default:
            mask = VINO_FRAMERT_FULL;
        }
        vcs->framert_reg = VINO_FRAMERT_RT(mask);
        break;
    case VINO_DATA_NORM_PAL:
    case VINO_DATA_NORM_SECAM:
        fps = (unsigned int)(fps / 5) * 5; // FIXME: round!

        if (fps < vino_data_norms[vcs->data_norm].fps_min)
            fps = vino_data_norms[vcs->data_norm].fps_min;
        if (fps > vino_data_norms[vcs->data_norm].fps_max)
            fps = vino_data_norms[vcs->data_norm].fps_max;

        switch (fps) {
        case 5:
            mask = 0x003;
            break;
        case 10:
            mask = 0x0c3;
            break;
        case 15:
            mask = 0x333;
            break;
        case 20:
            mask = 0x0ff;
            break;
        case 25:
            mask = 0x3ff;
            break;
        default:
            mask = VINO_FRAMERT_FULL;
        }
        vcs->framert_reg = VINO_FRAMERT_RT(mask) | VINO_FRAMERT_PAL;
        break;
    }

    vcs->fps = fps;
}

/* execute with input_lock locked */
static inline void vino_set_default_framerate(struct
                          vino_channel_settings *vcs)
{
    vino_set_framerate(vcs, vino_data_norms[vcs->data_norm].fps_max);
}

/* VINO I2C bus functions */

struct i2c_algo_sgi_data {
    void *data; /* private data for lowlevel routines */
    unsigned (*getctrl)(void *data);
    void (*setctrl)(void *data, unsigned val);
    unsigned (*rdata)(void *data);
    void (*wdata)(void *data, unsigned val);

    int xfer_timeout;
    int ack_timeout;
};

static int wait_xfer_done(struct i2c_algo_sgi_data *adap)
{
    int i;

    for (i = 0; i < adap->xfer_timeout; i++) {
        if ((adap->getctrl(adap->data) & SGI_I2C_XFER_BUSY) == 0)
            return 0;
        udelay(1);
    }

    return -ETIMEDOUT;
}

static int wait_ack(struct i2c_algo_sgi_data *adap)
{
    int i;

    if (wait_xfer_done(adap))
        return -ETIMEDOUT;
    for (i = 0; i < adap->ack_timeout; i++) {
        if ((adap->getctrl(adap->data) & SGI_I2C_NACK) == 0)
            return 0;
        udelay(1);
    }

    return -ETIMEDOUT;
}

static int force_idle(struct i2c_algo_sgi_data *adap)
{
    int i;

    adap->setctrl(adap->data, SGI_I2C_FORCE_IDLE);
    for (i = 0; i < adap->xfer_timeout; i++) {
        if ((adap->getctrl(adap->data) & SGI_I2C_NOT_IDLE) == 0)
            goto out;
        udelay(1);
    }
    return -ETIMEDOUT;
out:
    if (adap->getctrl(adap->data) & SGI_I2C_BUS_ERR)
        return -EIO;
    return 0;
}

static int do_address(struct i2c_algo_sgi_data *adap, unsigned int addr,
              int rd)
{
    if (rd)
        adap->setctrl(adap->data, SGI_I2C_NOT_IDLE);
    /* Check if bus is idle, eventually force it to do so */
    if (adap->getctrl(adap->data) & SGI_I2C_NOT_IDLE)
        if (force_idle(adap))
            return -EIO;
    /* Write out the i2c chip address and specify operation */
    adap->setctrl(adap->data,
              SGI_I2C_HOLD_BUS | SGI_I2C_WRITE | SGI_I2C_NOT_IDLE);
    if (rd)
        addr |= 1;
    adap->wdata(adap->data, addr);
    if (wait_ack(adap))
        return -EIO;
    return 0;
}

static int i2c_read(struct i2c_algo_sgi_data *adap, unsigned char *buf,
            unsigned int len)
{
    int i;

    adap->setctrl(adap->data,
              SGI_I2C_HOLD_BUS | SGI_I2C_READ | SGI_I2C_NOT_IDLE);
    for (i = 0; i < len; i++) {
        if (wait_xfer_done(adap))
            return -EIO;
        buf[i] = adap->rdata(adap->data);
    }
    adap->setctrl(adap->data, SGI_I2C_RELEASE_BUS | SGI_I2C_FORCE_IDLE);

    return 0;

}

static int i2c_write(struct i2c_algo_sgi_data *adap, unsigned char *buf,
             unsigned int len)
{
    int i;

    /* We are already in write state */
    for (i = 0; i < len; i++) {
        adap->wdata(adap->data, buf[i]);
        if (wait_ack(adap))
            return -EIO;
    }
    return 0;
}

static int sgi_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
            int num)
{
    struct i2c_algo_sgi_data *adap = i2c_adap->algo_data;
    struct i2c_msg *p;
    int i, err = 0;

    for (i = 0; !err && i < num; i++) {
        p = &msgs[i];
        err = do_address(adap, p->addr, p->flags & I2C_M_RD);
        if (err || !p->len)
            continue;
        if (p->flags & I2C_M_RD)
            err = i2c_read(adap, p->buf, p->len);
        else
            err = i2c_write(adap, p->buf, p->len);
    }

    return (err < 0) ? err : i;
}

static u32 sgi_func(struct i2c_adapter *adap)
{
    return I2C_FUNC_SMBUS_EMUL;
}

static const struct i2c_algorithm sgi_algo = {
    .master_xfer    = sgi_xfer,
    .functionality  = sgi_func,
};

static unsigned i2c_vino_getctrl(void *data)
{
    return vino->i2c_control;
}

static void i2c_vino_setctrl(void *data, unsigned val)
{
    vino->i2c_control = val;
}

static unsigned i2c_vino_rdata(void *data)
{
    return vino->i2c_data;
}

static void i2c_vino_wdata(void *data, unsigned val)
{
    vino->i2c_data = val;
}

static struct i2c_algo_sgi_data i2c_sgi_vino_data = {
    .getctrl = &i2c_vino_getctrl,
    .setctrl = &i2c_vino_setctrl,
    .rdata   = &i2c_vino_rdata,
    .wdata   = &i2c_vino_wdata,
    .xfer_timeout = 200,
    .ack_timeout  = 1000,
};

static struct i2c_adapter vino_i2c_adapter = {
    .name           = "VINO I2C bus",
    .algo           = &sgi_algo,
    .algo_data      = &i2c_sgi_vino_data,
    .owner          = THIS_MODULE,
};

/*
 * Prepare VINO for DMA transfer...
 * (execute only with vino_lock and input_lock locked)
 */
static int vino_dma_setup(struct vino_channel_settings *vcs,
              struct vino_framebuffer *fb)
{
    u32 ctrl, intr;
    struct sgi_vino_channel *ch;
    const struct vino_data_norm *norm;

    dprintk("vino_dma_setup():\n");

    vcs->field = 0;
    fb->frame_counter = 0;

    ch = (vcs->channel == VINO_CHANNEL_A) ? &vino->a : &vino->b;
    norm = &vino_data_norms[vcs->data_norm];

    ch->page_index = 0;
    ch->line_count = 0;

    /* VINO line size register is set 8 bytes less than actual */
    ch->line_size = vcs->line_size - 8;

    /* let VINO know where to transfer data */
    ch->start_desc_tbl = fb->desc_table.dma;
    ch->next_4_desc = fb->desc_table.dma;

    /* give vino time to fetch the first four descriptors, 5 usec
     * should be more than enough time */
    udelay(VINO_DESC_FETCH_DELAY);

    dprintk("vino_dma_setup(): start desc = %08x, next 4 desc = %08x\n",
        ch->start_desc_tbl, ch->next_4_desc);

    /* set the alpha register */
    ch->alpha = vcs->alpha;

    /* set clipping registers */
    ch->clip_start = VINO_CLIP_ODD(norm->odd.top + vcs->clipping.top / 2) |
        VINO_CLIP_EVEN(norm->even.top +
                   vcs->clipping.top / 2) |
        VINO_CLIP_X(vcs->clipping.left);
    ch->clip_end = VINO_CLIP_ODD(norm->odd.top +
                     vcs->clipping.bottom / 2 - 1) |
        VINO_CLIP_EVEN(norm->even.top +
                   vcs->clipping.bottom / 2 - 1) |
        VINO_CLIP_X(vcs->clipping.right);

    /* set the size of actual content in the buffer (DECIMATION !) */
    fb->data_size = ((vcs->clipping.right - vcs->clipping.left) /
             vcs->decimation) *
        ((vcs->clipping.bottom - vcs->clipping.top) /
         vcs->decimation) *
        vino_data_formats[vcs->data_format].bpp;

    ch->frame_rate = vcs->framert_reg;

    ctrl = vino->control;
    intr = vino->intr_status;

    if (vcs->channel == VINO_CHANNEL_A) {
        /* All interrupt conditions for this channel was cleared
         * so clear the interrupt status register and enable
         * interrupts */
        intr &= ~VINO_INTSTAT_A;
        ctrl |= VINO_CTRL_A_INT;

        /* enable synchronization */
        ctrl |= VINO_CTRL_A_SYNC_ENBL;

        /* enable frame assembly */
        ctrl |= VINO_CTRL_A_INTERLEAVE_ENBL;

        /* set decimation used */
        if (vcs->decimation < 2)
            ctrl &= ~VINO_CTRL_A_DEC_ENBL;
        else {
            ctrl |= VINO_CTRL_A_DEC_ENBL;
            ctrl &= ~VINO_CTRL_A_DEC_SCALE_MASK;
            ctrl |= (vcs->decimation - 1) <<
                VINO_CTRL_A_DEC_SCALE_SHIFT;
        }

        /* select input interface */
        if (vcs->input == VINO_INPUT_D1)
            ctrl |= VINO_CTRL_A_SELECT;
        else
            ctrl &= ~VINO_CTRL_A_SELECT;

        /* palette */
        ctrl &= ~(VINO_CTRL_A_LUMA_ONLY | VINO_CTRL_A_RGB |
              VINO_CTRL_A_DITHER);
    } else {
        intr &= ~VINO_INTSTAT_B;
        ctrl |= VINO_CTRL_B_INT;

        ctrl |= VINO_CTRL_B_SYNC_ENBL;
        ctrl |= VINO_CTRL_B_INTERLEAVE_ENBL;

        if (vcs->decimation < 2)
            ctrl &= ~VINO_CTRL_B_DEC_ENBL;
        else {
            ctrl |= VINO_CTRL_B_DEC_ENBL;
            ctrl &= ~VINO_CTRL_B_DEC_SCALE_MASK;
            ctrl |= (vcs->decimation - 1) <<
                VINO_CTRL_B_DEC_SCALE_SHIFT;

        }
        if (vcs->input == VINO_INPUT_D1)
            ctrl |= VINO_CTRL_B_SELECT;
        else
            ctrl &= ~VINO_CTRL_B_SELECT;

        ctrl &= ~(VINO_CTRL_B_LUMA_ONLY | VINO_CTRL_B_RGB |
              VINO_CTRL_B_DITHER);
    }

    /* set palette */
    fb->data_format = vcs->data_format;

    switch (vcs->data_format) {
        case VINO_DATA_FMT_GREY:
            ctrl |= (vcs->channel == VINO_CHANNEL_A) ?
                VINO_CTRL_A_LUMA_ONLY : VINO_CTRL_B_LUMA_ONLY;
            break;
        case VINO_DATA_FMT_RGB32:
            ctrl |= (vcs->channel == VINO_CHANNEL_A) ?
                VINO_CTRL_A_RGB : VINO_CTRL_B_RGB;
            break;
        case VINO_DATA_FMT_YUV:
            /* nothing needs to be done */
            break;
        case VINO_DATA_FMT_RGB332:
            ctrl |= (vcs->channel == VINO_CHANNEL_A) ?
                VINO_CTRL_A_RGB | VINO_CTRL_A_DITHER :
                VINO_CTRL_B_RGB | VINO_CTRL_B_DITHER;
            break;
    }

    vino->intr_status = intr;
    vino->control = ctrl;

    return 0;
}

/* (execute only with vino_lock locked) */
static inline void vino_dma_start(struct vino_channel_settings *vcs)
{
    u32 ctrl = vino->control;

    dprintk("vino_dma_start():\n");
    ctrl |= (vcs->channel == VINO_CHANNEL_A) ?
        VINO_CTRL_A_DMA_ENBL : VINO_CTRL_B_DMA_ENBL;
    vino->control = ctrl;
}

/* (execute only with vino_lock locked) */
static inline void vino_dma_stop(struct vino_channel_settings *vcs)
{
    u32 ctrl = vino->control;

    ctrl &= (vcs->channel == VINO_CHANNEL_A) ?
        ~VINO_CTRL_A_DMA_ENBL : ~VINO_CTRL_B_DMA_ENBL;
    ctrl &= (vcs->channel == VINO_CHANNEL_A) ?
        ~VINO_CTRL_A_INT : ~VINO_CTRL_B_INT;
    vino->control = ctrl;
    dprintk("vino_dma_stop():\n");
}

/*
 * Load dummy page to descriptor registers. This prevents generating of
 * spurious interrupts. (execute only with vino_lock locked)
 */
static void vino_clear_interrupt(struct vino_channel_settings *vcs)
{
    struct sgi_vino_channel *ch;

    ch = (vcs->channel == VINO_CHANNEL_A) ? &vino->a : &vino->b;

    ch->page_index = 0;
    ch->line_count = 0;

    ch->start_desc_tbl = vino_drvdata->dummy_desc_table.dma;
    ch->next_4_desc = vino_drvdata->dummy_desc_table.dma;

    udelay(VINO_DESC_FETCH_DELAY);
    dprintk("channel %c clear interrupt condition\n",
           (vcs->channel == VINO_CHANNEL_A) ? 'A':'B');
}

static int vino_capture(struct vino_channel_settings *vcs,
            struct vino_framebuffer *fb)
{
    int err = 0;
    unsigned long flags, flags2;

    spin_lock_irqsave(&fb->state_lock, flags);

    if (fb->state == VINO_FRAMEBUFFER_IN_USE)
        err = -EBUSY;
    fb->state = VINO_FRAMEBUFFER_IN_USE;

    spin_unlock_irqrestore(&fb->state_lock, flags);

    if (err)
        return err;

    spin_lock_irqsave(&vino_drvdata->vino_lock, flags);
    spin_lock_irqsave(&vino_drvdata->input_lock, flags2);

    vino_dma_setup(vcs, fb);
    vino_dma_start(vcs);

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags2);
    spin_unlock_irqrestore(&vino_drvdata->vino_lock, flags);

    return err;
}

static
struct vino_framebuffer *vino_capture_enqueue(struct
                          vino_channel_settings *vcs,
                          unsigned int index)
{
    struct vino_framebuffer *fb;
    unsigned long flags;

    dprintk("vino_capture_enqueue():\n");

    spin_lock_irqsave(&vcs->capture_lock, flags);

    fb = vino_queue_add(&vcs->fb_queue, index);
    if (fb == NULL) {
        dprintk("vino_capture_enqueue(): vino_queue_add() failed, "
            "queue full?\n");
        goto out;
    }
out:
    spin_unlock_irqrestore(&vcs->capture_lock, flags);

    return fb;
}

static int vino_capture_next(struct vino_channel_settings *vcs, int start)
{
    struct vino_framebuffer *fb;
    unsigned int incoming, id;
    int err = 0;
    unsigned long flags;

    dprintk("vino_capture_next():\n");

    spin_lock_irqsave(&vcs->capture_lock, flags);

    if (start) {
        /* start capture only if capture isn't in progress already */
        if (vcs->capturing) {
            spin_unlock_irqrestore(&vcs->capture_lock, flags);
            return 0;
        }

    } else {
        /* capture next frame:
         * stop capture if capturing is not set */
        if (!vcs->capturing) {
            spin_unlock_irqrestore(&vcs->capture_lock, flags);
            return 0;
        }
    }

    err = vino_queue_get_incoming(&vcs->fb_queue, &incoming);
    if (err) {
        dprintk("vino_capture_next(): vino_queue_get_incoming() "
            "failed\n");
        err = -EINVAL;
        goto out;
    }
    if (incoming == 0) {
        dprintk("vino_capture_next(): no buffers available\n");
        goto out;
    }

    fb = vino_queue_peek(&vcs->fb_queue, &id);
    if (fb == NULL) {
        dprintk("vino_capture_next(): vino_queue_peek() failed\n");
        err = -EINVAL;
        goto out;
    }

    if (start) {
        vcs->capturing = 1;
    }

    spin_unlock_irqrestore(&vcs->capture_lock, flags);

    err = vino_capture(vcs, fb);

    return err;

out:
    vcs->capturing = 0;
    spin_unlock_irqrestore(&vcs->capture_lock, flags);

    return err;
}

static inline int vino_is_capturing(struct vino_channel_settings *vcs)
{
    int ret;
    unsigned long flags;

    spin_lock_irqsave(&vcs->capture_lock, flags);

    ret = vcs->capturing;

    spin_unlock_irqrestore(&vcs->capture_lock, flags);

    return ret;
}

/* waits until a frame is captured */
static int vino_wait_for_frame(struct vino_channel_settings *vcs)
{
    wait_queue_t wait;
    int err = 0;

    dprintk("vino_wait_for_frame():\n");

    init_waitqueue_entry(&wait, current);
    /* add ourselves into wait queue */
    add_wait_queue(&vcs->fb_queue.frame_wait_queue, &wait);

    /* to ensure that schedule_timeout will return immediately
     * if VINO interrupt was triggered meanwhile */
    schedule_timeout_interruptible(msecs_to_jiffies(100));

    if (signal_pending(current))
        err = -EINTR;

    remove_wait_queue(&vcs->fb_queue.frame_wait_queue, &wait);

    dprintk("vino_wait_for_frame(): waiting for frame %s\n",
        err ? "failed" : "ok");

    return err;
}

/* the function assumes that PAGE_SIZE % 4 == 0 */
static void vino_convert_to_rgba(struct vino_framebuffer *fb) {
    unsigned char *pageptr;
    unsigned int page, i;
    unsigned char a;

    for (page = 0; page < fb->desc_table.page_count; page++) {
        pageptr = (unsigned char *)fb->desc_table.virtual[page];

        for (i = 0; i < PAGE_SIZE; i += 4) {
            a = pageptr[0];
            pageptr[0] = pageptr[3];
            pageptr[1] = pageptr[2];
            pageptr[2] = pageptr[1];
            pageptr[3] = a;
            pageptr += 4;
        }
    }
}

/* checks if the buffer is in correct state and syncs data */
static int vino_check_buffer(struct vino_channel_settings *vcs,
                 struct vino_framebuffer *fb)
{
    int err = 0;
    unsigned long flags;

    dprintk("vino_check_buffer():\n");

    spin_lock_irqsave(&fb->state_lock, flags);
    switch (fb->state) {
    case VINO_FRAMEBUFFER_IN_USE:
        err = -EIO;
        break;
    case VINO_FRAMEBUFFER_READY:
        vino_sync_buffer(fb);
        fb->state = VINO_FRAMEBUFFER_UNUSED;
        break;
    default:
        err = -EINVAL;
    }
    spin_unlock_irqrestore(&fb->state_lock, flags);

    if (!err) {
        if (vino_pixel_conversion
            && (fb->data_format == VINO_DATA_FMT_RGB32)) {
            vino_convert_to_rgba(fb);
        }
    } else if (err && (err != -EINVAL)) {
        dprintk("vino_check_buffer(): buffer not ready\n");

        spin_lock_irqsave(&vino_drvdata->vino_lock, flags);
        vino_dma_stop(vcs);
        vino_clear_interrupt(vcs);
        spin_unlock_irqrestore(&vino_drvdata->vino_lock, flags);
    }

    return err;
}

/* forcefully terminates capture */
static void vino_capture_stop(struct vino_channel_settings *vcs)
{
    unsigned int incoming = 0, outgoing = 0, id;
    unsigned long flags, flags2;

    dprintk("vino_capture_stop():\n");

    spin_lock_irqsave(&vcs->capture_lock, flags);

    /* unset capturing to stop queue processing */
    vcs->capturing = 0;

    spin_lock_irqsave(&vino_drvdata->vino_lock, flags2);

    vino_dma_stop(vcs);
    vino_clear_interrupt(vcs);

    spin_unlock_irqrestore(&vino_drvdata->vino_lock, flags2);

    /* remove all items from the queue */
    if (vino_queue_get_incoming(&vcs->fb_queue, &incoming)) {
        dprintk("vino_capture_stop(): "
            "vino_queue_get_incoming() failed\n");
        goto out;
    }
    while (incoming > 0) {
        vino_queue_transfer(&vcs->fb_queue);

        if (vino_queue_get_incoming(&vcs->fb_queue, &incoming)) {
            dprintk("vino_capture_stop(): "
                "vino_queue_get_incoming() failed\n");
            goto out;
        }
    }

    if (vino_queue_get_outgoing(&vcs->fb_queue, &outgoing)) {
        dprintk("vino_capture_stop(): "
            "vino_queue_get_outgoing() failed\n");
        goto out;
    }
    while (outgoing > 0) {
        vino_queue_remove(&vcs->fb_queue, &id);

        if (vino_queue_get_outgoing(&vcs->fb_queue, &outgoing)) {
            dprintk("vino_capture_stop(): "
                "vino_queue_get_outgoing() failed\n");
            goto out;
        }
    }

out:
    spin_unlock_irqrestore(&vcs->capture_lock, flags);
}

#if 0
static int vino_capture_failed(struct vino_channel_settings *vcs)
{
    struct vino_framebuffer *fb;
    unsigned long flags;
    unsigned int i;
    int ret;

    dprintk("vino_capture_failed():\n");

    spin_lock_irqsave(&vino_drvdata->vino_lock, flags);

    vino_dma_stop(vcs);
    vino_clear_interrupt(vcs);

    spin_unlock_irqrestore(&vino_drvdata->vino_lock, flags);

    ret = vino_queue_get_incoming(&vcs->fb_queue, &i);
    if (ret == VINO_QUEUE_ERROR) {
        dprintk("vino_queue_get_incoming() failed\n");
        return -EINVAL;
    }
    if (i == 0) {
        /* no buffers to process */
        return 0;
    }

    fb = vino_queue_peek(&vcs->fb_queue, &i);
    if (fb == NULL) {
        dprintk("vino_queue_peek() failed\n");
        return -EINVAL;
    }

    spin_lock_irqsave(&fb->state_lock, flags);
    if (fb->state == VINO_FRAMEBUFFER_IN_USE) {
        fb->state = VINO_FRAMEBUFFER_UNUSED;
        vino_queue_transfer(&vcs->fb_queue);
        vino_queue_remove(&vcs->fb_queue, &i);
        /* we should actually discard the newest frame,
         * but who cares ... */
    }
    spin_unlock_irqrestore(&fb->state_lock, flags);

    return 0;
}
#endif

static void vino_skip_frame(struct vino_channel_settings *vcs)
{
    struct vino_framebuffer *fb;
    unsigned long flags;
    unsigned int id;

    spin_lock_irqsave(&vcs->capture_lock, flags);
    fb = vino_queue_peek(&vcs->fb_queue, &id);
    if (!fb) {
        spin_unlock_irqrestore(&vcs->capture_lock, flags);
        dprintk("vino_skip_frame(): vino_queue_peek() failed!\n");
        return;
    }
    spin_unlock_irqrestore(&vcs->capture_lock, flags);

    spin_lock_irqsave(&fb->state_lock, flags);
    fb->state = VINO_FRAMEBUFFER_UNUSED;
    spin_unlock_irqrestore(&fb->state_lock, flags);

    vino_capture_next(vcs, 0);
}

static void vino_frame_done(struct vino_channel_settings *vcs)
{
    struct vino_framebuffer *fb;
    unsigned long flags;

    spin_lock_irqsave(&vcs->capture_lock, flags);
    fb = vino_queue_transfer(&vcs->fb_queue);
    if (!fb) {
        spin_unlock_irqrestore(&vcs->capture_lock, flags);
        dprintk("vino_frame_done(): vino_queue_transfer() failed!\n");
        return;
    }
    spin_unlock_irqrestore(&vcs->capture_lock, flags);

    fb->frame_counter = vcs->int_data.frame_counter;
    memcpy(&fb->timestamp, &vcs->int_data.timestamp,
           sizeof(struct timeval));

    spin_lock_irqsave(&fb->state_lock, flags);
    if (fb->state == VINO_FRAMEBUFFER_IN_USE)
        fb->state = VINO_FRAMEBUFFER_READY;
    spin_unlock_irqrestore(&fb->state_lock, flags);

    wake_up(&vcs->fb_queue.frame_wait_queue);

    vino_capture_next(vcs, 0);
}

static void vino_capture_tasklet(unsigned long channel) {
    struct vino_channel_settings *vcs;

    vcs = (channel == VINO_CHANNEL_A)
        ? &vino_drvdata->a : &vino_drvdata->b;

    if (vcs->int_data.skip)
        vcs->int_data.skip_count++;

    if (vcs->int_data.skip && (vcs->int_data.skip_count
                   <= VINO_MAX_FRAME_SKIP_COUNT)) {
        vino_skip_frame(vcs);
    } else {
        vcs->int_data.skip_count = 0;
        vino_frame_done(vcs);
    }
}

static irqreturn_t vino_interrupt(int irq, void *dev_id)
{
    u32 ctrl, intr;
    unsigned int fc_a, fc_b;
    int handled_a = 0, skip_a = 0, done_a = 0;
    int handled_b = 0, skip_b = 0, done_b = 0;

#ifdef VINO_DEBUG_INT
    int loop = 0;
    unsigned int line_count = vino->a.line_count,
        page_index = vino->a.page_index,
        field_counter = vino->a.field_counter,
        start_desc_tbl = vino->a.start_desc_tbl,
        next_4_desc = vino->a.next_4_desc;
    unsigned int line_count_2,
        page_index_2,
        field_counter_2,
        start_desc_tbl_2,
        next_4_desc_2;
#endif

    spin_lock(&vino_drvdata->vino_lock);

    while ((intr = vino->intr_status)) {
        fc_a = vino->a.field_counter >> 1;
        fc_b = vino->b.field_counter >> 1;

        /* handle error-interrupts in some special way ?
         * --> skips frames */
        if (intr & VINO_INTSTAT_A) {
            if (intr & VINO_INTSTAT_A_EOF) {
                vino_drvdata->a.field++;
                if (vino_drvdata->a.field > 1) {
                    vino_dma_stop(&vino_drvdata->a);
                    vino_clear_interrupt(&vino_drvdata->a);
                    vino_drvdata->a.field = 0;
                    done_a = 1;
                } else {
                    if (vino->a.page_index
                        != vino_drvdata->a.line_size) {
                        vino->a.line_count = 0;
                        vino->a.page_index =
                            vino_drvdata->
                            a.line_size;
                        vino->a.next_4_desc =
                            vino->a.start_desc_tbl;
                    }
                }
                dprintk("channel A end-of-field "
                    "interrupt: %04x\n", intr);
            } else {
                vino_dma_stop(&vino_drvdata->a);
                vino_clear_interrupt(&vino_drvdata->a);
                vino_drvdata->a.field = 0;
                skip_a = 1;
                dprintk("channel A error interrupt: %04x\n",
                    intr);
            }

#ifdef VINO_DEBUG_INT
            line_count_2 = vino->a.line_count;
            page_index_2 = vino->a.page_index;
            field_counter_2 = vino->a.field_counter;
            start_desc_tbl_2 = vino->a.start_desc_tbl;
            next_4_desc_2 = vino->a.next_4_desc;

            printk("intr = %04x, loop = %d, field = %d\n",
                   intr, loop, vino_drvdata->a.field);
            printk("1- line count = %04d, page index = %04d, "
                   "start = %08x, next = %08x\n"
                   "   fieldc = %d, framec = %d\n",
                   line_count, page_index, start_desc_tbl,
                   next_4_desc, field_counter, fc_a);
            printk("12-line count = %04d, page index = %04d, "
                   "   start = %08x, next = %08x\n",
                   line_count_2, page_index_2, start_desc_tbl_2,
                   next_4_desc_2);

            if (done_a)
                printk("\n");
#endif
        }

        if (intr & VINO_INTSTAT_B) {
            if (intr & VINO_INTSTAT_B_EOF) {
                vino_drvdata->b.field++;
                if (vino_drvdata->b.field > 1) {
                    vino_dma_stop(&vino_drvdata->b);
                    vino_clear_interrupt(&vino_drvdata->b);
                    vino_drvdata->b.field = 0;
                    done_b = 1;
                }
                dprintk("channel B end-of-field "
                    "interrupt: %04x\n", intr);
            } else {
                vino_dma_stop(&vino_drvdata->b);
                vino_clear_interrupt(&vino_drvdata->b);
                vino_drvdata->b.field = 0;
                skip_b = 1;
                dprintk("channel B error interrupt: %04x\n",
                    intr);
            }
        }

        /* Always remember to clear interrupt status.
         * Disable VINO interrupts while we do this. */
        ctrl = vino->control;
        vino->control = ctrl & ~(VINO_CTRL_A_INT | VINO_CTRL_B_INT);
        vino->intr_status = ~intr;
        vino->control = ctrl;

        spin_unlock(&vino_drvdata->vino_lock);

        if ((!handled_a) && (done_a || skip_a)) {
            if (!skip_a) {
                do_gettimeofday(&vino_drvdata->
                        a.int_data.timestamp);
                vino_drvdata->a.int_data.frame_counter = fc_a;
            }
            vino_drvdata->a.int_data.skip = skip_a;

            dprintk("channel A %s, interrupt: %d\n",
                skip_a ? "skipping frame" : "frame done",
                intr);
            tasklet_hi_schedule(&vino_tasklet_a);
            handled_a = 1;
        }

        if ((!handled_b) && (done_b || skip_b)) {
            if (!skip_b) {
                do_gettimeofday(&vino_drvdata->
                        b.int_data.timestamp);
                vino_drvdata->b.int_data.frame_counter = fc_b;
            }
            vino_drvdata->b.int_data.skip = skip_b;

            dprintk("channel B %s, interrupt: %d\n",
                skip_b ? "skipping frame" : "frame done",
                intr);
            tasklet_hi_schedule(&vino_tasklet_b);
            handled_b = 1;
        }

#ifdef VINO_DEBUG_INT
        loop++;
#endif
        spin_lock(&vino_drvdata->vino_lock);
    }

    spin_unlock(&vino_drvdata->vino_lock);

    return IRQ_HANDLED;
}

/* VINO video input management */

static int vino_get_saa7191_input(int input)
{
    switch (input) {
    case VINO_INPUT_COMPOSITE:
        return SAA7191_INPUT_COMPOSITE;
    case VINO_INPUT_SVIDEO:
        return SAA7191_INPUT_SVIDEO;
    default:
        printk(KERN_ERR "VINO: vino_get_saa7191_input(): "
               "invalid input!\n");
        return -1;
    }
}

/* execute with input_lock locked */
static int vino_is_input_owner(struct vino_channel_settings *vcs)
{
    switch(vcs->input) {
    case VINO_INPUT_COMPOSITE:
    case VINO_INPUT_SVIDEO:
        return vino_drvdata->decoder_owner == vcs->channel;
    case VINO_INPUT_D1:
        return vino_drvdata->camera_owner == vcs->channel;
    default:
        return 0;
    }
}

static int vino_acquire_input(struct vino_channel_settings *vcs)
{
    unsigned long flags;
    int ret = 0;

    dprintk("vino_acquire_input():\n");

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    /* First try D1 and then SAA7191 */
    if (vino_drvdata->camera
        && (vino_drvdata->camera_owner == VINO_NO_CHANNEL)) {
        vino_drvdata->camera_owner = vcs->channel;
        vcs->input = VINO_INPUT_D1;
        vcs->data_norm = VINO_DATA_NORM_D1;
    } else if (vino_drvdata->decoder
           && (vino_drvdata->decoder_owner == VINO_NO_CHANNEL)) {
        int input;
        int data_norm = 0;
        v4l2_std_id norm;

        input = VINO_INPUT_COMPOSITE;

        ret = decoder_call(video, s_routing,
                vino_get_saa7191_input(input), 0, 0);
        if (ret) {
            ret = -EINVAL;
            goto out;
        }

        spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

        /* Don't hold spinlocks while auto-detecting norm
         * as it may take a while... */

        ret = decoder_call(video, querystd, &norm);
        if (!ret) {
            for (data_norm = 0; data_norm < 3; data_norm++) {
                if (vino_data_norms[data_norm].std & norm)
                    break;
            }
            if (data_norm == 3)
                data_norm = VINO_DATA_NORM_PAL;
            ret = decoder_call(core, s_std, norm);
        }

        spin_lock_irqsave(&vino_drvdata->input_lock, flags);

        if (ret) {
            ret = -EINVAL;
            goto out;
        }

        vino_drvdata->decoder_owner = vcs->channel;

        vcs->input = input;
        vcs->data_norm = data_norm;
    } else {
        vcs->input = (vcs->channel == VINO_CHANNEL_A) ?
            vino_drvdata->b.input : vino_drvdata->a.input;
        vcs->data_norm = (vcs->channel == VINO_CHANNEL_A) ?
            vino_drvdata->b.data_norm : vino_drvdata->a.data_norm;
    }

    if (vcs->input == VINO_INPUT_NONE) {
        ret = -ENODEV;
        goto out;
    }

    vino_set_default_clipping(vcs);
    vino_set_default_scaling(vcs);
    vino_set_default_framerate(vcs);

    dprintk("vino_acquire_input(): %s\n", vino_inputs[vcs->input].name);

out:
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return ret;
}

static int vino_set_input(struct vino_channel_settings *vcs, int input)
{
    struct vino_channel_settings *vcs2 = (vcs->channel == VINO_CHANNEL_A) ?
        &vino_drvdata->b : &vino_drvdata->a;
    unsigned long flags;
    int ret = 0;

    dprintk("vino_set_input():\n");

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    if (vcs->input == input)
        goto out;

    switch (input) {
    case VINO_INPUT_COMPOSITE:
    case VINO_INPUT_SVIDEO:
        if (!vino_drvdata->decoder) {
            ret = -EINVAL;
            goto out;
        }

        if (vino_drvdata->decoder_owner == VINO_NO_CHANNEL) {
            vino_drvdata->decoder_owner = vcs->channel;
        }

        if (vino_drvdata->decoder_owner == vcs->channel) {
            int data_norm = 0;
            v4l2_std_id norm;

            ret = decoder_call(video, s_routing,
                    vino_get_saa7191_input(input), 0, 0);
            if (ret) {
                vino_drvdata->decoder_owner = VINO_NO_CHANNEL;
                ret = -EINVAL;
                goto out;
            }

            spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

            /* Don't hold spinlocks while auto-detecting norm
             * as it may take a while... */

            ret = decoder_call(video, querystd, &norm);
            if (!ret) {
                for (data_norm = 0; data_norm < 3; data_norm++) {
                    if (vino_data_norms[data_norm].std & norm)
                        break;
                }
                if (data_norm == 3)
                    data_norm = VINO_DATA_NORM_PAL;
                ret = decoder_call(core, s_std, norm);
            }

            spin_lock_irqsave(&vino_drvdata->input_lock, flags);

            if (ret) {
                vino_drvdata->decoder_owner = VINO_NO_CHANNEL;
                ret = -EINVAL;
                goto out;
            }

            vcs->input = input;
            vcs->data_norm = data_norm;
        } else {
            if (input != vcs2->input) {
                ret = -EBUSY;
                goto out;
            }

            vcs->input = input;
            vcs->data_norm = vcs2->data_norm;
        }

        if (vino_drvdata->camera_owner == vcs->channel) {
            /* Transfer the ownership or release the input */
            if (vcs2->input == VINO_INPUT_D1) {
                vino_drvdata->camera_owner = vcs2->channel;
            } else {
                vino_drvdata->camera_owner = VINO_NO_CHANNEL;
            }
        }
        break;
    case VINO_INPUT_D1:
        if (!vino_drvdata->camera) {
            ret = -EINVAL;
            goto out;
        }

        if (vino_drvdata->camera_owner == VINO_NO_CHANNEL)
            vino_drvdata->camera_owner = vcs->channel;

        if (vino_drvdata->decoder_owner == vcs->channel) {
            /* Transfer the ownership or release the input */
            if ((vcs2->input == VINO_INPUT_COMPOSITE) ||
                 (vcs2->input == VINO_INPUT_SVIDEO)) {
                vino_drvdata->decoder_owner = vcs2->channel;
            } else {
                vino_drvdata->decoder_owner = VINO_NO_CHANNEL;
            }
        }

        vcs->input = input;
        vcs->data_norm = VINO_DATA_NORM_D1;
        break;
    default:
        ret = -EINVAL;
        goto out;
    }

    vino_set_default_clipping(vcs);
    vino_set_default_scaling(vcs);
    vino_set_default_framerate(vcs);

    dprintk("vino_set_input(): %s\n", vino_inputs[vcs->input].name);

out:
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return ret;
}

static void vino_release_input(struct vino_channel_settings *vcs)
{
    struct vino_channel_settings *vcs2 = (vcs->channel == VINO_CHANNEL_A) ?
        &vino_drvdata->b : &vino_drvdata->a;
    unsigned long flags;

    dprintk("vino_release_input():\n");

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    /* Release ownership of the channel
     * and if the other channel takes input from
     * the same source, transfer the ownership */
    if (vino_drvdata->camera_owner == vcs->channel) {
        if (vcs2->input == VINO_INPUT_D1) {
            vino_drvdata->camera_owner = vcs2->channel;
        } else {
            vino_drvdata->camera_owner = VINO_NO_CHANNEL;
        }
    } else if (vino_drvdata->decoder_owner == vcs->channel) {
        if ((vcs2->input == VINO_INPUT_COMPOSITE) ||
             (vcs2->input == VINO_INPUT_SVIDEO)) {
            vino_drvdata->decoder_owner = vcs2->channel;
        } else {
            vino_drvdata->decoder_owner = VINO_NO_CHANNEL;
        }
    }
    vcs->input = VINO_INPUT_NONE;

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);
}

/* execute with input_lock locked */
static int vino_set_data_norm(struct vino_channel_settings *vcs,
                  unsigned int data_norm,
                  unsigned long *flags)
{
    int err = 0;

    if (data_norm == vcs->data_norm)
        return 0;

    switch (vcs->input) {
    case VINO_INPUT_D1:
        /* only one "norm" supported */
        if (data_norm != VINO_DATA_NORM_D1)
            return -EINVAL;
        break;
    case VINO_INPUT_COMPOSITE:
    case VINO_INPUT_SVIDEO: {
        v4l2_std_id norm;

        if ((data_norm != VINO_DATA_NORM_PAL)
            && (data_norm != VINO_DATA_NORM_NTSC)
            && (data_norm != VINO_DATA_NORM_SECAM))
            return -EINVAL;

        spin_unlock_irqrestore(&vino_drvdata->input_lock, *flags);

        /* Don't hold spinlocks while setting norm
         * as it may take a while... */

        norm = vino_data_norms[data_norm].std;
        err = decoder_call(core, s_std, norm);

        spin_lock_irqsave(&vino_drvdata->input_lock, *flags);

        if (err)
            goto out;

        vcs->data_norm = data_norm;

        vino_set_default_clipping(vcs);
        vino_set_default_scaling(vcs);
        vino_set_default_framerate(vcs);
        break;
    }
    default:
        return -EINVAL;
    }

out:
    return err;
}

/* V4L2 helper functions */

static int vino_find_data_format(__u32 pixelformat)
{
    int i;

    for (i = 0; i < VINO_DATA_FMT_COUNT; i++) {
        if (vino_data_formats[i].pixelformat == pixelformat)
            return i;
    }

    return VINO_DATA_FMT_NONE;
}

static int vino_int_enum_input(struct vino_channel_settings *vcs, __u32 index)
{
    int input = VINO_INPUT_NONE;
    unsigned long flags;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);
    if (vino_drvdata->decoder && vino_drvdata->camera) {
        switch (index) {
        case 0:
            input = VINO_INPUT_COMPOSITE;
            break;
        case 1:
            input = VINO_INPUT_SVIDEO;
            break;
        case 2:
            input = VINO_INPUT_D1;
            break;
        }
    } else if (vino_drvdata->decoder) {
        switch (index) {
        case 0:
            input = VINO_INPUT_COMPOSITE;
            break;
        case 1:
            input = VINO_INPUT_SVIDEO;
            break;
        }
    } else if (vino_drvdata->camera) {
        switch (index) {
        case 0:
            input = VINO_INPUT_D1;
            break;
        }
    }
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return input;
}

/* execute with input_lock locked */
static __u32 vino_find_input_index(struct vino_channel_settings *vcs)
{
    __u32 index = 0;
    // FIXME: detect when no inputs available

    if (vino_drvdata->decoder && vino_drvdata->camera) {
        switch (vcs->input) {
        case VINO_INPUT_COMPOSITE:
            index = 0;
            break;
        case VINO_INPUT_SVIDEO:
            index = 1;
            break;
        case VINO_INPUT_D1:
            index = 2;
            break;
        }
    } else if (vino_drvdata->decoder) {
        switch (vcs->input) {
        case VINO_INPUT_COMPOSITE:
            index = 0;
            break;
        case VINO_INPUT_SVIDEO:
            index = 1;
            break;
        }
    } else if (vino_drvdata->camera) {
        switch (vcs->input) {
        case VINO_INPUT_D1:
            index = 0;
            break;
        }
    }

    return index;
}

/* V4L2 ioctls */

static int vino_querycap(struct file *file, void *__fh,
        struct v4l2_capability *cap)
{
    memset(cap, 0, sizeof(struct v4l2_capability));

    strcpy(cap->driver, vino_driver_name);
    strcpy(cap->card, vino_driver_description);
    strcpy(cap->bus_info, vino_bus_name);
    cap->capabilities =
        V4L2_CAP_VIDEO_CAPTURE |
        V4L2_CAP_STREAMING;
    // V4L2_CAP_OVERLAY, V4L2_CAP_READWRITE
    return 0;
}

static int vino_enum_input(struct file *file, void *__fh,
                   struct v4l2_input *i)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    __u32 index = i->index;
    int input;
    dprintk("requested index = %d\n", index);

    input = vino_int_enum_input(vcs, index);
    if (input == VINO_INPUT_NONE)
        return -EINVAL;

    i->type = V4L2_INPUT_TYPE_CAMERA;
    i->std = vino_inputs[input].std;
    strcpy(i->name, vino_inputs[input].name);

    if (input == VINO_INPUT_COMPOSITE || input == VINO_INPUT_SVIDEO)
        decoder_call(video, g_input_status, &i->status);
    return 0;
}

static int vino_g_input(struct file *file, void *__fh,
                 unsigned int *i)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    __u32 index;
    int input;
    unsigned long flags;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);
    input = vcs->input;
    index = vino_find_input_index(vcs);
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    dprintk("input = %d\n", input);

    if (input == VINO_INPUT_NONE) {
        return -EINVAL;
    }

    *i = index;

    return 0;
}

static int vino_s_input(struct file *file, void *__fh,
                 unsigned int i)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    int input;
    dprintk("requested input = %d\n", i);

    input = vino_int_enum_input(vcs, i);
    if (input == VINO_INPUT_NONE)
        return -EINVAL;

    return vino_set_input(vcs, input);
}

static int vino_querystd(struct file *file, void *__fh,
                  v4l2_std_id *std)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    int err = 0;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    switch (vcs->input) {
    case VINO_INPUT_D1:
        *std = vino_inputs[vcs->input].std;
        break;
    case VINO_INPUT_COMPOSITE:
    case VINO_INPUT_SVIDEO: {
        decoder_call(video, querystd, std);
        break;
    }
    default:
        err = -EINVAL;
    }

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return err;
}

static int vino_g_std(struct file *file, void *__fh,
               v4l2_std_id *std)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    *std = vino_data_norms[vcs->data_norm].std;
    dprintk("current standard = %d\n", vcs->data_norm);

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return 0;
}

static int vino_s_std(struct file *file, void *__fh,
               v4l2_std_id *std)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    int ret = 0;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    if (!vino_is_input_owner(vcs)) {
        ret = -EBUSY;
        goto out;
    }

    /* check if the standard is valid for the current input */
    if ((*std) & vino_inputs[vcs->input].std) {
        dprintk("standard accepted\n");

        /* change the video norm for SAA7191
         * and accept NTSC for D1 (do nothing) */

        if (vcs->input == VINO_INPUT_D1)
            goto out;

        if ((*std) & V4L2_STD_PAL) {
            ret = vino_set_data_norm(vcs, VINO_DATA_NORM_PAL,
                         &flags);
        } else if ((*std) & V4L2_STD_NTSC) {
            ret = vino_set_data_norm(vcs, VINO_DATA_NORM_NTSC,
                         &flags);
        } else if ((*std) & V4L2_STD_SECAM) {
            ret = vino_set_data_norm(vcs, VINO_DATA_NORM_SECAM,
                         &flags);
        } else {
            ret = -EINVAL;
        }

        if (ret) {
            ret = -EINVAL;
        }
    } else {
        ret = -EINVAL;
    }

out:
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return ret;
}

static int vino_enum_fmt_vid_cap(struct file *file, void *__fh,
                  struct v4l2_fmtdesc *fd)
{
    dprintk("format index = %d\n", fd->index);

    if (fd->index >= VINO_DATA_FMT_COUNT)
        return -EINVAL;
    dprintk("format name = %s\n", vino_data_formats[fd->index].description);

    fd->pixelformat = vino_data_formats[fd->index].pixelformat;
    strcpy(fd->description, vino_data_formats[fd->index].description);
    return 0;
}

static int vino_try_fmt_vid_cap(struct file *file, void *__fh,
                 struct v4l2_format *f)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    struct vino_channel_settings tempvcs;
    unsigned long flags;
    struct v4l2_pix_format *pf = &f->fmt.pix;

    dprintk("requested: w = %d, h = %d\n",
            pf->width, pf->height);

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);
    memcpy(&tempvcs, vcs, sizeof(struct vino_channel_settings));
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    tempvcs.data_format = vino_find_data_format(pf->pixelformat);
    if (tempvcs.data_format == VINO_DATA_FMT_NONE) {
        tempvcs.data_format = VINO_DATA_FMT_GREY;
        pf->pixelformat =
            vino_data_formats[tempvcs.data_format].
            pixelformat;
    }

    /* data format must be set before clipping/scaling */
    vino_set_scaling(&tempvcs, pf->width, pf->height);

    dprintk("data format = %s\n",
            vino_data_formats[tempvcs.data_format].description);

    pf->width = (tempvcs.clipping.right - tempvcs.clipping.left) /
        tempvcs.decimation;
    pf->height = (tempvcs.clipping.bottom - tempvcs.clipping.top) /
        tempvcs.decimation;

    pf->field = V4L2_FIELD_INTERLACED;
    pf->bytesperline = tempvcs.line_size;
    pf->sizeimage = tempvcs.line_size *
        (tempvcs.clipping.bottom - tempvcs.clipping.top) /
        tempvcs.decimation;
    pf->colorspace =
        vino_data_formats[tempvcs.data_format].colorspace;

    pf->priv = 0;
    return 0;
}

static int vino_g_fmt_vid_cap(struct file *file, void *__fh,
               struct v4l2_format *f)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    struct v4l2_pix_format *pf = &f->fmt.pix;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    pf->width = (vcs->clipping.right - vcs->clipping.left) /
        vcs->decimation;
    pf->height = (vcs->clipping.bottom - vcs->clipping.top) /
        vcs->decimation;
    pf->pixelformat =
        vino_data_formats[vcs->data_format].pixelformat;

    pf->field = V4L2_FIELD_INTERLACED;
    pf->bytesperline = vcs->line_size;
    pf->sizeimage = vcs->line_size *
        (vcs->clipping.bottom - vcs->clipping.top) /
        vcs->decimation;
    pf->colorspace =
        vino_data_formats[vcs->data_format].colorspace;

    pf->priv = 0;

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);
    return 0;
}

static int vino_s_fmt_vid_cap(struct file *file, void *__fh,
               struct v4l2_format *f)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    int data_format;
    unsigned long flags;
    struct v4l2_pix_format *pf = &f->fmt.pix;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    data_format = vino_find_data_format(pf->pixelformat);

    if (data_format == VINO_DATA_FMT_NONE) {
        vcs->data_format = VINO_DATA_FMT_GREY;
        pf->pixelformat =
            vino_data_formats[vcs->data_format].
            pixelformat;
    } else {
        vcs->data_format = data_format;
    }

    /* data format must be set before clipping/scaling */
    vino_set_scaling(vcs, pf->width, pf->height);

    dprintk("data format = %s\n",
           vino_data_formats[vcs->data_format].description);

    pf->width = vcs->clipping.right - vcs->clipping.left;
    pf->height = vcs->clipping.bottom - vcs->clipping.top;

    pf->field = V4L2_FIELD_INTERLACED;
    pf->bytesperline = vcs->line_size;
    pf->sizeimage = vcs->line_size *
        (vcs->clipping.bottom - vcs->clipping.top) /
        vcs->decimation;
    pf->colorspace =
        vino_data_formats[vcs->data_format].colorspace;

    pf->priv = 0;

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);
    return 0;
}

static int vino_cropcap(struct file *file, void *__fh,
                 struct v4l2_cropcap *ccap)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    const struct vino_data_norm *norm;
    unsigned long flags;

    switch (ccap->type) {
    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
        spin_lock_irqsave(&vino_drvdata->input_lock, flags);

        norm = &vino_data_norms[vcs->data_norm];

        spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

        ccap->bounds.left = 0;
        ccap->bounds.top = 0;
        ccap->bounds.width = norm->width;
        ccap->bounds.height = norm->height;
        memcpy(&ccap->defrect, &ccap->bounds,
               sizeof(struct v4l2_rect));

        ccap->pixelaspect.numerator = 1;
        ccap->pixelaspect.denominator = 1;
        break;
    case V4L2_BUF_TYPE_VIDEO_OVERLAY:
    default:
        return -EINVAL;
    }

    return 0;
}

static int vino_g_crop(struct file *file, void *__fh,
                struct v4l2_crop *c)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;

    switch (c->type) {
    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
        spin_lock_irqsave(&vino_drvdata->input_lock, flags);

        c->c.left = vcs->clipping.left;
        c->c.top = vcs->clipping.top;
        c->c.width = vcs->clipping.right - vcs->clipping.left;
        c->c.height = vcs->clipping.bottom - vcs->clipping.top;

        spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);
        break;
    case V4L2_BUF_TYPE_VIDEO_OVERLAY:
    default:
        return -EINVAL;
    }

    return 0;
}

static int vino_s_crop(struct file *file, void *__fh,
                const struct v4l2_crop *c)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;

    switch (c->type) {
    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
        spin_lock_irqsave(&vino_drvdata->input_lock, flags);

        vino_set_clipping(vcs, c->c.left, c->c.top,
                  c->c.width, c->c.height);

        spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);
        break;
    case V4L2_BUF_TYPE_VIDEO_OVERLAY:
    default:
        return -EINVAL;
    }

    return 0;
}

static int vino_g_parm(struct file *file, void *__fh,
                struct v4l2_streamparm *sp)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    struct v4l2_captureparm *cp = &sp->parm.capture;

    cp->capability = V4L2_CAP_TIMEPERFRAME;
    cp->timeperframe.numerator = 1;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    cp->timeperframe.denominator = vcs->fps;

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    /* TODO: cp->readbuffers = xxx; */

    return 0;
}

static int vino_s_parm(struct file *file, void *__fh,
                struct v4l2_streamparm *sp)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    struct v4l2_captureparm *cp = &sp->parm.capture;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    if ((cp->timeperframe.numerator == 0) ||
        (cp->timeperframe.denominator == 0)) {
        /* reset framerate */
        vino_set_default_framerate(vcs);
    } else {
        vino_set_framerate(vcs, cp->timeperframe.denominator /
                   cp->timeperframe.numerator);
    }

    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return 0;
}

static int vino_reqbufs(struct file *file, void *__fh,
                 struct v4l2_requestbuffers *rb)
{
    struct vino_channel_settings *vcs = video_drvdata(file);

    if (vcs->reading)
        return -EBUSY;

    /* TODO: check queue type */
    if (rb->memory != V4L2_MEMORY_MMAP) {
        dprintk("type not mmap\n");
        return -EINVAL;
    }

    dprintk("count = %d\n", rb->count);
    if (rb->count > 0) {
        if (vino_is_capturing(vcs)) {
            dprintk("busy, capturing\n");
            return -EBUSY;
        }

        if (vino_queue_has_mapped_buffers(&vcs->fb_queue)) {
            dprintk("busy, buffers still mapped\n");
            return -EBUSY;
        } else {
            vcs->streaming = 0;
            vino_queue_free(&vcs->fb_queue);
            vino_queue_init(&vcs->fb_queue, &rb->count);
        }
    } else {
        vcs->streaming = 0;
        vino_capture_stop(vcs);
        vino_queue_free(&vcs->fb_queue);
    }

    return 0;
}

static void vino_v4l2_get_buffer_status(struct vino_channel_settings *vcs,
                    struct vino_framebuffer *fb,
                    struct v4l2_buffer *b)
{
    if (vino_queue_outgoing_contains(&vcs->fb_queue,
                     fb->id)) {
        b->flags &= ~V4L2_BUF_FLAG_QUEUED;
        b->flags |= V4L2_BUF_FLAG_DONE;
    } else if (vino_queue_incoming_contains(&vcs->fb_queue,
                       fb->id)) {
        b->flags &= ~V4L2_BUF_FLAG_DONE;
        b->flags |= V4L2_BUF_FLAG_QUEUED;
    } else {
        b->flags &= ~(V4L2_BUF_FLAG_DONE |
                  V4L2_BUF_FLAG_QUEUED);
    }

    b->flags &= ~(V4L2_BUF_FLAG_TIMECODE);

    if (fb->map_count > 0)
        b->flags |= V4L2_BUF_FLAG_MAPPED;

    b->index = fb->id;
    b->memory = (vcs->fb_queue.type == VINO_MEMORY_MMAP) ?
        V4L2_MEMORY_MMAP : V4L2_MEMORY_USERPTR;
    b->m.offset = fb->offset;
    b->bytesused = fb->data_size;
    b->length = fb->size;
    b->field = V4L2_FIELD_INTERLACED;
    b->sequence = fb->frame_counter;
    memcpy(&b->timestamp, &fb->timestamp,
           sizeof(struct timeval));
    // b->input ?

    dprintk("buffer %d: length = %d, bytesused = %d, offset = %d\n",
        fb->id, fb->size, fb->data_size, fb->offset);
}

static int vino_querybuf(struct file *file, void *__fh,
                  struct v4l2_buffer *b)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    struct vino_framebuffer *fb;

    if (vcs->reading)
        return -EBUSY;

    /* TODO: check queue type */
    if (b->index >= vino_queue_get_length(&vcs->fb_queue)) {
        dprintk("invalid index = %d\n",
               b->index);
        return -EINVAL;
    }

    fb = vino_queue_get_buffer(&vcs->fb_queue,
                   b->index);
    if (fb == NULL) {
        dprintk("vino_queue_get_buffer() failed");
        return -EINVAL;
    }

    vino_v4l2_get_buffer_status(vcs, fb, b);

    return 0;
}

static int vino_qbuf(struct file *file, void *__fh,
              struct v4l2_buffer *b)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    struct vino_framebuffer *fb;
    int ret;

    if (vcs->reading)
        return -EBUSY;

    /* TODO: check queue type */
    if (b->memory != V4L2_MEMORY_MMAP) {
        dprintk("type not mmap\n");
        return -EINVAL;
    }

    fb = vino_capture_enqueue(vcs, b->index);
    if (fb == NULL)
        return -EINVAL;

    vino_v4l2_get_buffer_status(vcs, fb, b);

    if (vcs->streaming) {
        ret = vino_capture_next(vcs, 1);
        if (ret)
            return ret;
    }

    return 0;
}

static int vino_dqbuf(struct file *file, void *__fh,
               struct v4l2_buffer *b)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned int nonblocking = file->f_flags & O_NONBLOCK;
    struct vino_framebuffer *fb;
    unsigned int incoming, outgoing;
    int err;

    if (vcs->reading)
        return -EBUSY;

    /* TODO: check queue type */

    err = vino_queue_get_incoming(&vcs->fb_queue, &incoming);
    if (err) {
        dprintk("vino_queue_get_incoming() failed\n");
        return -EINVAL;
    }
    err = vino_queue_get_outgoing(&vcs->fb_queue, &outgoing);
    if (err) {
        dprintk("vino_queue_get_outgoing() failed\n");
        return -EINVAL;
    }

    dprintk("incoming = %d, outgoing = %d\n", incoming, outgoing);

    if (outgoing == 0) {
        if (incoming == 0) {
            dprintk("no incoming or outgoing buffers\n");
            return -EINVAL;
        }
        if (nonblocking) {
            dprintk("non-blocking I/O was selected and "
                "there are no buffers to dequeue\n");
            return -EAGAIN;
        }

        err = vino_wait_for_frame(vcs);
        if (err) {
            err = vino_wait_for_frame(vcs);
            if (err) {
                /* interrupted or no frames captured because of
                 * frame skipping */
                /* vino_capture_failed(vcs); */
                return -EIO;
            }
        }
    }

    fb = vino_queue_remove(&vcs->fb_queue, &b->index);
    if (fb == NULL) {
        dprintk("vino_queue_remove() failed\n");
        return -EINVAL;
    }

    err = vino_check_buffer(vcs, fb);

    vino_v4l2_get_buffer_status(vcs, fb, b);

    if (err)
        return -EIO;

    return 0;
}

static int vino_streamon(struct file *file, void *__fh,
        enum v4l2_buf_type i)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned int incoming;
    int ret;
    if (vcs->reading)
        return -EBUSY;

    if (vcs->streaming)
        return 0;

    // TODO: check queue type

    if (vino_queue_get_length(&vcs->fb_queue) < 1) {
        dprintk("no buffers allocated\n");
        return -EINVAL;
    }

    ret = vino_queue_get_incoming(&vcs->fb_queue, &incoming);
    if (ret) {
        dprintk("vino_queue_get_incoming() failed\n");
        return -EINVAL;
    }

    vcs->streaming = 1;

    if (incoming > 0) {
        ret = vino_capture_next(vcs, 1);
        if (ret) {
            vcs->streaming = 0;

            dprintk("couldn't start capture\n");
            return -EINVAL;
        }
    }

    return 0;
}

static int vino_streamoff(struct file *file, void *__fh,
        enum v4l2_buf_type i)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    if (vcs->reading)
        return -EBUSY;

    if (!vcs->streaming)
        return 0;

    vcs->streaming = 0;
    vino_capture_stop(vcs);

    return 0;
}

static int vino_queryctrl(struct file *file, void *__fh,
                   struct v4l2_queryctrl *queryctrl)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    int i;
    int err = 0;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    switch (vcs->input) {
    case VINO_INPUT_D1:
        for (i = 0; i < VINO_INDYCAM_V4L2_CONTROL_COUNT; i++) {
            if (vino_indycam_v4l2_controls[i].id ==
                queryctrl->id) {
                memcpy(queryctrl,
                       &vino_indycam_v4l2_controls[i],
                       sizeof(struct v4l2_queryctrl));
                queryctrl->reserved[0] = 0;
                goto found;
            }
        }

        err =  -EINVAL;
        break;
    case VINO_INPUT_COMPOSITE:
    case VINO_INPUT_SVIDEO:
        for (i = 0; i < VINO_SAA7191_V4L2_CONTROL_COUNT; i++) {
            if (vino_saa7191_v4l2_controls[i].id ==
                queryctrl->id) {
                memcpy(queryctrl,
                       &vino_saa7191_v4l2_controls[i],
                       sizeof(struct v4l2_queryctrl));
                queryctrl->reserved[0] = 0;
                goto found;
            }
        }

        err =  -EINVAL;
        break;
    default:
        err =  -EINVAL;
    }

 found:
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return err;
}

static int vino_g_ctrl(struct file *file, void *__fh,
                struct v4l2_control *control)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    int i;
    int err = 0;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    switch (vcs->input) {
    case VINO_INPUT_D1: {
        err = -EINVAL;
        for (i = 0; i < VINO_INDYCAM_V4L2_CONTROL_COUNT; i++) {
            if (vino_indycam_v4l2_controls[i].id == control->id) {
                err = 0;
                break;
            }
        }

        if (err)
            goto out;

        err = camera_call(core, g_ctrl, control);
        if (err)
            err = -EINVAL;
        break;
    }
    case VINO_INPUT_COMPOSITE:
    case VINO_INPUT_SVIDEO: {
        err = -EINVAL;
        for (i = 0; i < VINO_SAA7191_V4L2_CONTROL_COUNT; i++) {
            if (vino_saa7191_v4l2_controls[i].id == control->id) {
                err = 0;
                break;
            }
        }

        if (err)
            goto out;

        err = decoder_call(core, g_ctrl, control);
        if (err)
            err = -EINVAL;
        break;
    }
    default:
        err =  -EINVAL;
    }

out:
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return err;
}

static int vino_s_ctrl(struct file *file, void *__fh,
                struct v4l2_control *control)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned long flags;
    int i;
    int err = 0;

    spin_lock_irqsave(&vino_drvdata->input_lock, flags);

    if (!vino_is_input_owner(vcs)) {
        err = -EBUSY;
        goto out;
    }

    switch (vcs->input) {
    case VINO_INPUT_D1: {
        err = -EINVAL;
        for (i = 0; i < VINO_INDYCAM_V4L2_CONTROL_COUNT; i++) {
            if (vino_indycam_v4l2_controls[i].id == control->id) {
                err = 0;
                break;
            }
        }
        if (err)
            goto out;
        if (control->value < vino_indycam_v4l2_controls[i].minimum ||
            control->value > vino_indycam_v4l2_controls[i].maximum) {
            err = -ERANGE;
            goto out;
        }
        err = camera_call(core, s_ctrl, control);
        if (err)
            err = -EINVAL;
        break;
    }
    case VINO_INPUT_COMPOSITE:
    case VINO_INPUT_SVIDEO: {
        err = -EINVAL;
        for (i = 0; i < VINO_SAA7191_V4L2_CONTROL_COUNT; i++) {
            if (vino_saa7191_v4l2_controls[i].id == control->id) {
                err = 0;
                break;
            }
        }
        if (err)
            goto out;
        if (control->value < vino_saa7191_v4l2_controls[i].minimum ||
            control->value > vino_saa7191_v4l2_controls[i].maximum) {
            err = -ERANGE;
            goto out;
        }

        err = decoder_call(core, s_ctrl, control);
        if (err)
            err = -EINVAL;
        break;
    }
    default:
        err =  -EINVAL;
    }

out:
    spin_unlock_irqrestore(&vino_drvdata->input_lock, flags);

    return err;
}

/* File operations */

static int vino_open(struct file *file)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    int ret = 0;
    dprintk("open(): channel = %c\n",
           (vcs->channel == VINO_CHANNEL_A) ? 'A' : 'B');

    mutex_lock(&vcs->mutex);

    if (vcs->users) {
        dprintk("open(): driver busy\n");
        ret = -EBUSY;
        goto out;
    }

    ret = vino_acquire_input(vcs);
    if (ret) {
        dprintk("open(): vino_acquire_input() failed\n");
        goto out;
    }

    vcs->users++;

 out:
    mutex_unlock(&vcs->mutex);

    dprintk("open(): %s!\n", ret ? "failed" : "complete");

    return ret;
}

static int vino_close(struct file *file)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    dprintk("close():\n");

    mutex_lock(&vcs->mutex);

    vcs->users--;

    if (!vcs->users) {
        vino_release_input(vcs);

        /* stop DMA and free buffers */
        vino_capture_stop(vcs);
        vino_queue_free(&vcs->fb_queue);
    }

    mutex_unlock(&vcs->mutex);

    return 0;
}

static void vino_vm_open(struct vm_area_struct *vma)
{
    struct vino_framebuffer *fb = vma->vm_private_data;

    fb->map_count++;
    dprintk("vino_vm_open(): count = %d\n", fb->map_count);
}

static void vino_vm_close(struct vm_area_struct *vma)
{
    struct vino_framebuffer *fb = vma->vm_private_data;

    fb->map_count--;
    dprintk("vino_vm_close(): count = %d\n", fb->map_count);
}

static const struct vm_operations_struct vino_vm_ops = {
    .open   = vino_vm_open,
    .close  = vino_vm_close,
};

static int vino_mmap(struct file *file, struct vm_area_struct *vma)
{
    struct vino_channel_settings *vcs = video_drvdata(file);

    unsigned long start = vma->vm_start;
    unsigned long size = vma->vm_end - vma->vm_start;
    unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;

    struct vino_framebuffer *fb = NULL;
    unsigned int i, length;
    int ret = 0;

    dprintk("mmap():\n");

    // TODO: reject mmap if already mapped

    if (mutex_lock_interruptible(&vcs->mutex))
        return -EINTR;

    if (vcs->reading) {
        ret = -EBUSY;
        goto out;
    }

    // TODO: check queue type

    if (!(vma->vm_flags & VM_WRITE)) {
        dprintk("mmap(): app bug: PROT_WRITE please\n");
        ret = -EINVAL;
        goto out;
    }
    if (!(vma->vm_flags & VM_SHARED)) {
        dprintk("mmap(): app bug: MAP_SHARED please\n");
        ret = -EINVAL;
        goto out;
    }

    /* find the correct buffer using offset */
    length = vino_queue_get_length(&vcs->fb_queue);
    if (length == 0) {
        dprintk("mmap(): queue not initialized\n");
        ret = -EINVAL;
        goto out;
    }

    for (i = 0; i < length; i++) {
        fb = vino_queue_get_buffer(&vcs->fb_queue, i);
        if (fb == NULL) {
            dprintk("mmap(): vino_queue_get_buffer() failed\n");
            ret = -EINVAL;
            goto out;
        }

        if (fb->offset == offset)
            goto found;
    }

    dprintk("mmap(): invalid offset = %lu\n", offset);
    ret = -EINVAL;
    goto out;

found:
    dprintk("mmap(): buffer = %d\n", i);

    if (size > (fb->desc_table.page_count * PAGE_SIZE)) {
        dprintk("mmap(): failed: size = %lu > %lu\n",
            size, fb->desc_table.page_count * PAGE_SIZE);
        ret = -EINVAL;
        goto out;
    }

    for (i = 0; i < fb->desc_table.page_count; i++) {
        unsigned long pfn =
            virt_to_phys((void *)fb->desc_table.virtual[i]) >>
            PAGE_SHIFT;

        if (size < PAGE_SIZE)
            break;

        // protection was: PAGE_READONLY
        if (remap_pfn_range(vma, start, pfn, PAGE_SIZE,
                    vma->vm_page_prot)) {
            dprintk("mmap(): remap_pfn_range() failed\n");
            ret = -EAGAIN;
            goto out;
        }

        start += PAGE_SIZE;
        size -= PAGE_SIZE;
    }

    fb->map_count = 1;

    vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
    vma->vm_flags &= ~VM_IO;
    vma->vm_private_data = fb;
    vma->vm_file = file;
    vma->vm_ops = &vino_vm_ops;

out:
    mutex_unlock(&vcs->mutex);

    return ret;
}

static unsigned int vino_poll(struct file *file, poll_table *pt)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    unsigned int outgoing;
    unsigned int ret = 0;

    // lock mutex (?)
    // TODO: this has to be corrected for different read modes

    dprintk("poll():\n");

    if (vino_queue_get_outgoing(&vcs->fb_queue, &outgoing)) {
        dprintk("poll(): vino_queue_get_outgoing() failed\n");
        ret = POLLERR;
        goto error;
    }
    if (outgoing > 0)
        goto over;

    poll_wait(file, &vcs->fb_queue.frame_wait_queue, pt);

    if (vino_queue_get_outgoing(&vcs->fb_queue, &outgoing)) {
        dprintk("poll(): vino_queue_get_outgoing() failed\n");
        ret = POLLERR;
        goto error;
    }

over:
    dprintk("poll(): data %savailable\n",
        (outgoing > 0) ? "" : "not ");

    if (outgoing > 0)
        ret = POLLIN | POLLRDNORM;

error:
    return ret;
}

static long vino_ioctl(struct file *file,
              unsigned int cmd, unsigned long arg)
{
    struct vino_channel_settings *vcs = video_drvdata(file);
    long ret;

    if (mutex_lock_interruptible(&vcs->mutex))
        return -EINTR;

    ret = video_ioctl2(file, cmd, arg);

    mutex_unlock(&vcs->mutex);

    return ret;
}

/* Initialization and cleanup */

/* __initdata */
static int vino_init_stage;

const struct v4l2_ioctl_ops vino_ioctl_ops = {
    .vidioc_enum_fmt_vid_cap     = vino_enum_fmt_vid_cap,
    .vidioc_g_fmt_vid_cap        = vino_g_fmt_vid_cap,
    .vidioc_s_fmt_vid_cap        = vino_s_fmt_vid_cap,
    .vidioc_try_fmt_vid_cap      = vino_try_fmt_vid_cap,
    .vidioc_querycap             = vino_querycap,
    .vidioc_enum_input           = vino_enum_input,
    .vidioc_g_input              = vino_g_input,
    .vidioc_s_input              = vino_s_input,
    .vidioc_g_std            = vino_g_std,
    .vidioc_s_std            = vino_s_std,
    .vidioc_querystd             = vino_querystd,
    .vidioc_cropcap              = vino_cropcap,
    .vidioc_s_crop               = vino_s_crop,
    .vidioc_g_crop               = vino_g_crop,
    .vidioc_s_parm           = vino_s_parm,
    .vidioc_g_parm           = vino_g_parm,
    .vidioc_reqbufs              = vino_reqbufs,
    .vidioc_querybuf             = vino_querybuf,
    .vidioc_qbuf                 = vino_qbuf,
    .vidioc_dqbuf                = vino_dqbuf,
    .vidioc_streamon             = vino_streamon,
    .vidioc_streamoff            = vino_streamoff,
    .vidioc_queryctrl            = vino_queryctrl,
    .vidioc_g_ctrl               = vino_g_ctrl,
    .vidioc_s_ctrl               = vino_s_ctrl,
};

static const struct v4l2_file_operations vino_fops = {
    .owner      = THIS_MODULE,
    .open       = vino_open,
    .release    = vino_close,
    .unlocked_ioctl = vino_ioctl,
    .mmap       = vino_mmap,
    .poll       = vino_poll,
};

static struct video_device vdev_template = {
    .name       = "NOT SET",
    .fops       = &vino_fops,
    .ioctl_ops  = &vino_ioctl_ops,
    .tvnorms    = V4L2_STD_NTSC | V4L2_STD_PAL | V4L2_STD_SECAM,
};

static void vino_module_cleanup(int stage)
{
    switch(stage) {
    case 11:
        video_unregister_device(vino_drvdata->b.vdev);
        vino_drvdata->b.vdev = NULL;
    case 10:
        video_unregister_device(vino_drvdata->a.vdev);
        vino_drvdata->a.vdev = NULL;
    case 9:
        i2c_del_adapter(&vino_i2c_adapter);
    case 8:
        free_irq(SGI_VINO_IRQ, NULL);
    case 7:
        if (vino_drvdata->b.vdev) {
            video_device_release(vino_drvdata->b.vdev);
            vino_drvdata->b.vdev = NULL;
        }
    case 6:
        if (vino_drvdata->a.vdev) {
            video_device_release(vino_drvdata->a.vdev);
            vino_drvdata->a.vdev = NULL;
        }
    case 5:
        /* all entries in dma_cpu dummy table have the same address */
        dma_unmap_single(NULL,
                 vino_drvdata->dummy_desc_table.dma_cpu[0],
                 PAGE_SIZE, DMA_FROM_DEVICE);
        dma_free_coherent(NULL, VINO_DUMMY_DESC_COUNT
                  * sizeof(dma_addr_t),
                  (void *)vino_drvdata->
                  dummy_desc_table.dma_cpu,
                  vino_drvdata->dummy_desc_table.dma);
    case 4:
        free_page(vino_drvdata->dummy_page);
    case 3:
        v4l2_device_unregister(&vino_drvdata->v4l2_dev);
    case 2:
        kfree(vino_drvdata);
    case 1:
        iounmap(vino);
    case 0:
        break;
    default:
        dprintk("vino_module_cleanup(): invalid cleanup stage = %d\n",
            stage);
    }
}

static int vino_probe(void)
{
    unsigned long rev_id;

    if (ip22_is_fullhouse()) {
        printk(KERN_ERR "VINO doesn't exist in IP22 Fullhouse\n");
        return -ENODEV;
    }

    if (!(sgimc->systemid & SGIMC_SYSID_EPRESENT)) {
        printk(KERN_ERR "VINO is not found (EISA BUS not present)\n");
        return -ENODEV;
    }

    vino = (struct sgi_vino *)ioremap(VINO_BASE, sizeof(struct sgi_vino));
    if (!vino) {
        printk(KERN_ERR "VINO: ioremap() failed\n");
        return -EIO;
    }
    vino_init_stage++;

    if (get_dbe(rev_id, &(vino->rev_id))) {
        printk(KERN_ERR "Failed to read VINO revision register\n");
        vino_module_cleanup(vino_init_stage);
        return -ENODEV;
    }

    if (VINO_ID_VALUE(rev_id) != VINO_CHIP_ID) {
        printk(KERN_ERR "Unknown VINO chip ID (Rev/ID: 0x%02lx)\n",
               rev_id);
        vino_module_cleanup(vino_init_stage);
        return -ENODEV;
    }

    printk(KERN_INFO "VINO revision %ld found\n", VINO_REV_NUM(rev_id));

    return 0;
}

static int vino_init(void)
{
    dma_addr_t dma_dummy_address;
    int err;
    int i;

    vino_drvdata = kzalloc(sizeof(struct vino_settings), GFP_KERNEL);
    if (!vino_drvdata) {
        vino_module_cleanup(vino_init_stage);
        return -ENOMEM;
    }
    vino_init_stage++;
    strlcpy(vino_drvdata->v4l2_dev.name, "vino",
            sizeof(vino_drvdata->v4l2_dev.name));
    err = v4l2_device_register(NULL, &vino_drvdata->v4l2_dev);
    if (err)
        return err;
    vino_init_stage++;

    /* create a dummy dma descriptor */
    vino_drvdata->dummy_page = get_zeroed_page(GFP_KERNEL | GFP_DMA);
    if (!vino_drvdata->dummy_page) {
        vino_module_cleanup(vino_init_stage);
        return -ENOMEM;
    }
    vino_init_stage++;

    // TODO: use page_count in dummy_desc_table

    vino_drvdata->dummy_desc_table.dma_cpu =
        dma_alloc_coherent(NULL,
        VINO_DUMMY_DESC_COUNT * sizeof(dma_addr_t),
        &vino_drvdata->dummy_desc_table.dma,
        GFP_KERNEL | GFP_DMA);
    if (!vino_drvdata->dummy_desc_table.dma_cpu) {
        vino_module_cleanup(vino_init_stage);
        return -ENOMEM;
    }
    vino_init_stage++;

    dma_dummy_address = dma_map_single(NULL,
                       (void *)vino_drvdata->dummy_page,
                    PAGE_SIZE, DMA_FROM_DEVICE);
    for (i = 0; i < VINO_DUMMY_DESC_COUNT; i++) {
        vino_drvdata->dummy_desc_table.dma_cpu[i] = dma_dummy_address;
    }

    /* initialize VINO */

    vino->control = 0;
    vino->a.next_4_desc = vino_drvdata->dummy_desc_table.dma;
    vino->b.next_4_desc = vino_drvdata->dummy_desc_table.dma;
    udelay(VINO_DESC_FETCH_DELAY);

    vino->intr_status = 0;

    vino->a.fifo_thres = VINO_FIFO_THRESHOLD_DEFAULT;
    vino->b.fifo_thres = VINO_FIFO_THRESHOLD_DEFAULT;

    return 0;
}

static int vino_init_channel_settings(struct vino_channel_settings *vcs,
                 unsigned int channel, const char *name)
{
    vcs->channel = channel;
    vcs->input = VINO_INPUT_NONE;
    vcs->alpha = 0;
    vcs->users = 0;
    vcs->data_format = VINO_DATA_FMT_GREY;
    vcs->data_norm = VINO_DATA_NORM_NTSC;
    vcs->decimation = 1;
    vino_set_default_clipping(vcs);
    vino_set_default_framerate(vcs);

    vcs->capturing = 0;

    mutex_init(&vcs->mutex);
    spin_lock_init(&vcs->capture_lock);

    mutex_init(&vcs->fb_queue.queue_mutex);
    spin_lock_init(&vcs->fb_queue.queue_lock);
    init_waitqueue_head(&vcs->fb_queue.frame_wait_queue);

    vcs->vdev = video_device_alloc();
    if (!vcs->vdev) {
        vino_module_cleanup(vino_init_stage);
        return -ENOMEM;
    }
    vino_init_stage++;

    memcpy(vcs->vdev, &vdev_template,
           sizeof(struct video_device));
    strcpy(vcs->vdev->name, name);
    vcs->vdev->release = video_device_release;
    vcs->vdev->v4l2_dev = &vino_drvdata->v4l2_dev;

    video_set_drvdata(vcs->vdev, vcs);

    return 0;
}

static int __init vino_module_init(void)
{
    int ret;

    printk(KERN_INFO "SGI VINO driver version %s\n",
           VINO_MODULE_VERSION);

    ret = vino_probe();
    if (ret)
        return ret;

    ret = vino_init();
    if (ret)
        return ret;

    /* initialize data structures */

    spin_lock_init(&vino_drvdata->vino_lock);
    spin_lock_init(&vino_drvdata->input_lock);

    ret = vino_init_channel_settings(&vino_drvdata->a, VINO_CHANNEL_A,
                    vino_vdev_name_a);
    if (ret)
        return ret;

    ret = vino_init_channel_settings(&vino_drvdata->b, VINO_CHANNEL_B,
                    vino_vdev_name_b);
    if (ret)
        return ret;

    /* initialize hardware and register V4L devices */

    ret = request_irq(SGI_VINO_IRQ, vino_interrupt, 0,
        vino_driver_description, NULL);
    if (ret) {
        printk(KERN_ERR "VINO: requesting IRQ %02d failed\n",
               SGI_VINO_IRQ);
        vino_module_cleanup(vino_init_stage);
        return -EAGAIN;
    }
    vino_init_stage++;

    ret = i2c_add_adapter(&vino_i2c_adapter);
    if (ret) {
        printk(KERN_ERR "VINO I2C bus registration failed\n");
        vino_module_cleanup(vino_init_stage);
        return ret;
    }
    i2c_set_adapdata(&vino_i2c_adapter, &vino_drvdata->v4l2_dev);
    vino_init_stage++;

    ret = video_register_device(vino_drvdata->a.vdev,
                    VFL_TYPE_GRABBER, -1);
    if (ret < 0) {
        printk(KERN_ERR "VINO channel A Video4Linux-device "
               "registration failed\n");
        vino_module_cleanup(vino_init_stage);
        return -EINVAL;
    }
    vino_init_stage++;

    ret = video_register_device(vino_drvdata->b.vdev,
                    VFL_TYPE_GRABBER, -1);
    if (ret < 0) {
        printk(KERN_ERR "VINO channel B Video4Linux-device "
               "registration failed\n");
        vino_module_cleanup(vino_init_stage);
        return -EINVAL;
    }
    vino_init_stage++;

    vino_drvdata->decoder =
        v4l2_i2c_new_subdev(&vino_drvdata->v4l2_dev, &vino_i2c_adapter,
                   "saa7191", 0, I2C_ADDRS(0x45));
    vino_drvdata->camera =
        v4l2_i2c_new_subdev(&vino_drvdata->v4l2_dev, &vino_i2c_adapter,
                   "indycam", 0, I2C_ADDRS(0x2b));

    dprintk("init complete!\n");

    return 0;
}

static void __exit vino_module_exit(void)
{
    dprintk("exiting, stage = %d ...\n", vino_init_stage);
    vino_module_cleanup(vino_init_stage);
    dprintk("cleanup complete, exit!\n");
}

module_init(vino_module_init);
module_exit(vino_module_exit);