cx18-streams.c

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/*
 *  cx18 init/start/stop/exit stream functions
 *
 *  Derived from ivtv-streams.c
 *
 *  Copyright (C) 2007  Hans Verkuil <[email protected]>
 *  Copyright (C) 2008  Andy Walls <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 *  02111-1307  USA
 */

#include "cx18-driver.h"
#include "cx18-io.h"
#include "cx18-fileops.h"
#include "cx18-mailbox.h"
#include "cx18-i2c.h"
#include "cx18-queue.h"
#include "cx18-ioctl.h"
#include "cx18-streams.h"
#include "cx18-cards.h"
#include "cx18-scb.h"
#include "cx18-dvb.h"

#define CX18_DSP0_INTERRUPT_MASK        0xd0004C

static struct v4l2_file_operations cx18_v4l2_enc_fops = {
    .owner = THIS_MODULE,
    .read = cx18_v4l2_read,
    .open = cx18_v4l2_open,
    .unlocked_ioctl = video_ioctl2,
    .release = cx18_v4l2_close,
    .poll = cx18_v4l2_enc_poll,
    .mmap = cx18_v4l2_mmap,
};

/* offset from 0 to register ts v4l2 minors on */
#define CX18_V4L2_ENC_TS_OFFSET   16
/* offset from 0 to register pcm v4l2 minors on */
#define CX18_V4L2_ENC_PCM_OFFSET  24
/* offset from 0 to register yuv v4l2 minors on */
#define CX18_V4L2_ENC_YUV_OFFSET  32

static struct {
    const char *name;
    int vfl_type;
    int num_offset;
    int dma;
} cx18_stream_info[] = {
    {   /* CX18_ENC_STREAM_TYPE_MPG */
        "encoder MPEG",
        VFL_TYPE_GRABBER, 0,
        PCI_DMA_FROMDEVICE,
    },
    {   /* CX18_ENC_STREAM_TYPE_TS */
        "TS",
        VFL_TYPE_GRABBER, -1,
        PCI_DMA_FROMDEVICE,
    },
    {   /* CX18_ENC_STREAM_TYPE_YUV */
        "encoder YUV",
        VFL_TYPE_GRABBER, CX18_V4L2_ENC_YUV_OFFSET,
        PCI_DMA_FROMDEVICE,
    },
    {   /* CX18_ENC_STREAM_TYPE_VBI */
        "encoder VBI",
        VFL_TYPE_VBI, 0,
        PCI_DMA_FROMDEVICE,
    },
    {   /* CX18_ENC_STREAM_TYPE_PCM */
        "encoder PCM audio",
        VFL_TYPE_GRABBER, CX18_V4L2_ENC_PCM_OFFSET,
        PCI_DMA_FROMDEVICE,
    },
    {   /* CX18_ENC_STREAM_TYPE_IDX */
        "encoder IDX",
        VFL_TYPE_GRABBER, -1,
        PCI_DMA_FROMDEVICE,
    },
    {   /* CX18_ENC_STREAM_TYPE_RAD */
        "encoder radio",
        VFL_TYPE_RADIO, 0,
        PCI_DMA_NONE,
    },
};


void cx18_dma_free(struct videobuf_queue *q,
    struct cx18_stream *s, struct cx18_videobuf_buffer *buf)
{
    videobuf_waiton(q, &buf->vb, 0, 0);
    videobuf_vmalloc_free(&buf->vb);
    buf->vb.state = VIDEOBUF_NEEDS_INIT;
}

static int cx18_prepare_buffer(struct videobuf_queue *q,
    struct cx18_stream *s,
    struct cx18_videobuf_buffer *buf,
    u32 pixelformat,
    unsigned int width, unsigned int height,
    enum v4l2_field field)
{
        struct cx18 *cx = s->cx;
    int rc = 0;

    /* check settings */
    buf->bytes_used = 0;

    if ((width  < 48) || (height < 32))
        return -EINVAL;

    buf->vb.size = (width * height * 2);
    if ((buf->vb.baddr != 0) && (buf->vb.bsize < buf->vb.size))
        return -EINVAL;

    /* alloc + fill struct (if changed) */
    if (buf->vb.width != width || buf->vb.height != height ||
        buf->vb.field != field || s->pixelformat != pixelformat ||
        buf->tvnorm != cx->std) {

        buf->vb.width  = width;
        buf->vb.height = height;
        buf->vb.field  = field;
        buf->tvnorm    = cx->std;
        s->pixelformat = pixelformat;

        /* HM12 YUV size is (Y=(h*720) + UV=(h*(720/2)))
           UYUV YUV size is (Y=(h*720) + UV=(h*(720))) */
        if (s->pixelformat == V4L2_PIX_FMT_HM12)
            s->vb_bytes_per_frame = height * 720 * 3 / 2;
        else
            s->vb_bytes_per_frame = height * 720 * 2;
        cx18_dma_free(q, s, buf);
    }

    if ((buf->vb.baddr != 0) && (buf->vb.bsize < buf->vb.size))
        return -EINVAL;

    if (buf->vb.field == 0)
        buf->vb.field = V4L2_FIELD_INTERLACED;

    if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
        buf->vb.width  = width;
        buf->vb.height = height;
        buf->vb.field  = field;
        buf->tvnorm    = cx->std;
        s->pixelformat = pixelformat;

        /* HM12 YUV size is (Y=(h*720) + UV=(h*(720/2)))
           UYUV YUV size is (Y=(h*720) + UV=(h*(720))) */
        if (s->pixelformat == V4L2_PIX_FMT_HM12)
            s->vb_bytes_per_frame = height * 720 * 3 / 2;
        else
            s->vb_bytes_per_frame = height * 720 * 2;
        rc = videobuf_iolock(q, &buf->vb, NULL);
        if (rc != 0)
            goto fail;
    }
    buf->vb.state = VIDEOBUF_PREPARED;
    return 0;

fail:
    cx18_dma_free(q, s, buf);
    return rc;

}

/* VB_MIN_BUFSIZE is lcm(1440 * 480, 1440 * 576)
   1440 is a single line of 4:2:2 YUV at 720 luma samples wide
*/
#define VB_MIN_BUFFERS 32
#define VB_MIN_BUFSIZE 4147200

static int buffer_setup(struct videobuf_queue *q,
    unsigned int *count, unsigned int *size)
{
    struct cx18_stream *s = q->priv_data;
    struct cx18 *cx = s->cx;

    *size = 2 * cx->cxhdl.width * cx->cxhdl.height;
    if (*count == 0)
        *count = VB_MIN_BUFFERS;

    while (*size * *count > VB_MIN_BUFFERS * VB_MIN_BUFSIZE)
        (*count)--;

    q->field = V4L2_FIELD_INTERLACED;
    q->last = V4L2_FIELD_INTERLACED;

    return 0;
}

static int buffer_prepare(struct videobuf_queue *q,
    struct videobuf_buffer *vb,
    enum v4l2_field field)
{
    struct cx18_videobuf_buffer *buf =
        container_of(vb, struct cx18_videobuf_buffer, vb);
    struct cx18_stream *s = q->priv_data;
    struct cx18 *cx = s->cx;

    return cx18_prepare_buffer(q, s, buf, s->pixelformat,
        cx->cxhdl.width, cx->cxhdl.height, field);
}

static void buffer_release(struct videobuf_queue *q,
    struct videobuf_buffer *vb)
{
    struct cx18_videobuf_buffer *buf =
        container_of(vb, struct cx18_videobuf_buffer, vb);
    struct cx18_stream *s = q->priv_data;

    cx18_dma_free(q, s, buf);
}

static void buffer_queue(struct videobuf_queue *q, struct videobuf_buffer *vb)
{
    struct cx18_videobuf_buffer *buf =
        container_of(vb, struct cx18_videobuf_buffer, vb);
    struct cx18_stream *s = q->priv_data;

    buf->vb.state = VIDEOBUF_QUEUED;

    list_add_tail(&buf->vb.queue, &s->vb_capture);
}

static struct videobuf_queue_ops cx18_videobuf_qops = {
    .buf_setup    = buffer_setup,
    .buf_prepare  = buffer_prepare,
    .buf_queue    = buffer_queue,
    .buf_release  = buffer_release,
};

static void cx18_stream_init(struct cx18 *cx, int type)
{
    struct cx18_stream *s = &cx->streams[type];
    struct video_device *video_dev = s->video_dev;

    /* we need to keep video_dev, so restore it afterwards */
    memset(s, 0, sizeof(*s));
    s->video_dev = video_dev;

    /* initialize cx18_stream fields */
    s->dvb = NULL;
    s->cx = cx;
    s->type = type;
    s->name = cx18_stream_info[type].name;
    s->handle = CX18_INVALID_TASK_HANDLE;

    s->dma = cx18_stream_info[type].dma;
    s->buffers = cx->stream_buffers[type];
    s->buf_size = cx->stream_buf_size[type];
    INIT_LIST_HEAD(&s->buf_pool);
    s->bufs_per_mdl = 1;
    s->mdl_size = s->buf_size * s->bufs_per_mdl;

    init_waitqueue_head(&s->waitq);
    s->id = -1;
    spin_lock_init(&s->q_free.lock);
    cx18_queue_init(&s->q_free);
    spin_lock_init(&s->q_busy.lock);
    cx18_queue_init(&s->q_busy);
    spin_lock_init(&s->q_full.lock);
    cx18_queue_init(&s->q_full);
    spin_lock_init(&s->q_idle.lock);
    cx18_queue_init(&s->q_idle);

    INIT_WORK(&s->out_work_order, cx18_out_work_handler);

    INIT_LIST_HEAD(&s->vb_capture);
    s->vb_timeout.function = cx18_vb_timeout;
    s->vb_timeout.data = (unsigned long)s;
    init_timer(&s->vb_timeout);
    spin_lock_init(&s->vb_lock);
    if (type == CX18_ENC_STREAM_TYPE_YUV) {
        spin_lock_init(&s->vbuf_q_lock);

        s->vb_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        videobuf_queue_vmalloc_init(&s->vbuf_q, &cx18_videobuf_qops,
            &cx->pci_dev->dev, &s->vbuf_q_lock,
            V4L2_BUF_TYPE_VIDEO_CAPTURE,
            V4L2_FIELD_INTERLACED,
            sizeof(struct cx18_videobuf_buffer),
            s, &cx->serialize_lock);

        /* Assume the previous pixel default */
        s->pixelformat = V4L2_PIX_FMT_HM12;
        s->vb_bytes_per_frame = cx->cxhdl.height * 720 * 3 / 2;
    }
}

static int cx18_prep_dev(struct cx18 *cx, int type)
{
    struct cx18_stream *s = &cx->streams[type];
    u32 cap = cx->v4l2_cap;
    int num_offset = cx18_stream_info[type].num_offset;
    int num = cx->instance + cx18_first_minor + num_offset;

    /*
     * These five fields are always initialized.
     * For analog capture related streams, if video_dev == NULL then the
     * stream is not in use.
     * For the TS stream, if dvb == NULL then the stream is not in use.
     * In those cases no other fields but these four can be used.
     */
    s->video_dev = NULL;
    s->dvb = NULL;
    s->cx = cx;
    s->type = type;
    s->name = cx18_stream_info[type].name;

    /* Check whether the radio is supported */
    if (type == CX18_ENC_STREAM_TYPE_RAD && !(cap & V4L2_CAP_RADIO))
        return 0;

    /* Check whether VBI is supported */
    if (type == CX18_ENC_STREAM_TYPE_VBI &&
        !(cap & (V4L2_CAP_VBI_CAPTURE | V4L2_CAP_SLICED_VBI_CAPTURE)))
        return 0;

    /* User explicitly selected 0 buffers for these streams, so don't
       create them. */
    if (cx18_stream_info[type].dma != PCI_DMA_NONE &&
        cx->stream_buffers[type] == 0) {
        CX18_INFO("Disabled %s device\n", cx18_stream_info[type].name);
        return 0;
    }

    cx18_stream_init(cx, type);

    /* Allocate the cx18_dvb struct only for the TS on cards with DTV */
    if (type == CX18_ENC_STREAM_TYPE_TS) {
        if (cx->card->hw_all & CX18_HW_DVB) {
            s->dvb = kzalloc(sizeof(struct cx18_dvb), GFP_KERNEL);
            if (s->dvb == NULL) {
                CX18_ERR("Couldn't allocate cx18_dvb structure"
                     " for %s\n", s->name);
                return -ENOMEM;
            }
        } else {
            /* Don't need buffers for the TS, if there is no DVB */
            s->buffers = 0;
        }
    }

    if (num_offset == -1)
        return 0;

    /* allocate and initialize the v4l2 video device structure */
    s->video_dev = video_device_alloc();
    if (s->video_dev == NULL) {
        CX18_ERR("Couldn't allocate v4l2 video_device for %s\n",
                s->name);
        return -ENOMEM;
    }

    snprintf(s->video_dev->name, sizeof(s->video_dev->name), "%s %s",
         cx->v4l2_dev.name, s->name);

    s->video_dev->num = num;
    s->video_dev->v4l2_dev = &cx->v4l2_dev;
    s->video_dev->fops = &cx18_v4l2_enc_fops;
    s->video_dev->release = video_device_release;
    s->video_dev->tvnorms = V4L2_STD_ALL;
    s->video_dev->lock = &cx->serialize_lock;
    set_bit(V4L2_FL_USE_FH_PRIO, &s->video_dev->flags);
    cx18_set_funcs(s->video_dev);
    return 0;
}

/* Initialize v4l2 variables and register v4l2 devices */
int cx18_streams_setup(struct cx18 *cx)
{
    int type, ret;

    /* Setup V4L2 Devices */
    for (type = 0; type < CX18_MAX_STREAMS; type++) {
        /* Prepare device */
        ret = cx18_prep_dev(cx, type);
        if (ret < 0)
            break;

        /* Allocate Stream */
        ret = cx18_stream_alloc(&cx->streams[type]);
        if (ret < 0)
            break;
    }
    if (type == CX18_MAX_STREAMS)
        return 0;

    /* One or more streams could not be initialized. Clean 'em all up. */
    cx18_streams_cleanup(cx, 0);
    return ret;
}

static int cx18_reg_dev(struct cx18 *cx, int type)
{
    struct cx18_stream *s = &cx->streams[type];
    int vfl_type = cx18_stream_info[type].vfl_type;
    const char *name;
    int num, ret;

    if (type == CX18_ENC_STREAM_TYPE_TS && s->dvb != NULL) {
        ret = cx18_dvb_register(s);
        if (ret < 0) {
            CX18_ERR("DVB failed to register\n");
            return ret;
        }
    }

    if (s->video_dev == NULL)
        return 0;

    num = s->video_dev->num;
    /* card number + user defined offset + device offset */
    if (type != CX18_ENC_STREAM_TYPE_MPG) {
        struct cx18_stream *s_mpg = &cx->streams[CX18_ENC_STREAM_TYPE_MPG];

        if (s_mpg->video_dev)
            num = s_mpg->video_dev->num
                + cx18_stream_info[type].num_offset;
    }
    video_set_drvdata(s->video_dev, s);

    /* Register device. First try the desired minor, then any free one. */
    ret = video_register_device_no_warn(s->video_dev, vfl_type, num);
    if (ret < 0) {
        CX18_ERR("Couldn't register v4l2 device for %s (device node number %d)\n",
            s->name, num);
        video_device_release(s->video_dev);
        s->video_dev = NULL;
        return ret;
    }

    name = video_device_node_name(s->video_dev);

    switch (vfl_type) {
    case VFL_TYPE_GRABBER:
        CX18_INFO("Registered device %s for %s (%d x %d.%02d kB)\n",
              name, s->name, cx->stream_buffers[type],
              cx->stream_buf_size[type] / 1024,
              (cx->stream_buf_size[type] * 100 / 1024) % 100);
        break;

    case VFL_TYPE_RADIO:
        CX18_INFO("Registered device %s for %s\n", name, s->name);
        break;

    case VFL_TYPE_VBI:
        if (cx->stream_buffers[type])
            CX18_INFO("Registered device %s for %s "
                  "(%d x %d bytes)\n",
                  name, s->name, cx->stream_buffers[type],
                  cx->stream_buf_size[type]);
        else
            CX18_INFO("Registered device %s for %s\n",
                name, s->name);
        break;
    }

    return 0;
}

/* Register v4l2 devices */
int cx18_streams_register(struct cx18 *cx)
{
    int type;
    int err;
    int ret = 0;

    /* Register V4L2 devices */
    for (type = 0; type < CX18_MAX_STREAMS; type++) {
        err = cx18_reg_dev(cx, type);
        if (err && ret == 0)
            ret = err;
    }

    if (ret == 0)
        return 0;

    /* One or more streams could not be initialized. Clean 'em all up. */
    cx18_streams_cleanup(cx, 1);
    return ret;
}

/* Unregister v4l2 devices */
void cx18_streams_cleanup(struct cx18 *cx, int unregister)
{
    struct video_device *vdev;
    int type;

    /* Teardown all streams */
    for (type = 0; type < CX18_MAX_STREAMS; type++) {

        /* The TS has a cx18_dvb structure, not a video_device */
        if (type == CX18_ENC_STREAM_TYPE_TS) {
            if (cx->streams[type].dvb != NULL) {
                if (unregister)
                    cx18_dvb_unregister(&cx->streams[type]);
                kfree(cx->streams[type].dvb);
                cx->streams[type].dvb = NULL;
                cx18_stream_free(&cx->streams[type]);
            }
            continue;
        }

        /* No struct video_device, but can have buffers allocated */
        if (type == CX18_ENC_STREAM_TYPE_IDX) {
            /* If the module params didn't inhibit IDX ... */
            if (cx->stream_buffers[type] != 0) {
                cx->stream_buffers[type] = 0;
                /*
                 * Before calling cx18_stream_free(),
                 * check if the IDX stream was actually set up.
                 * Needed, since the cx18_probe() error path
                 * exits through here as well as normal clean up
                 */
                if (cx->streams[type].buffers != 0)
                    cx18_stream_free(&cx->streams[type]);
            }
            continue;
        }

        /* If struct video_device exists, can have buffers allocated */
        vdev = cx->streams[type].video_dev;

        cx->streams[type].video_dev = NULL;
        if (vdev == NULL)
            continue;

        if (type == CX18_ENC_STREAM_TYPE_YUV)
            videobuf_mmap_free(&cx->streams[type].vbuf_q);

        cx18_stream_free(&cx->streams[type]);

        /* Unregister or release device */
        if (unregister)
            video_unregister_device(vdev);
        else
            video_device_release(vdev);
    }
}

static void cx18_vbi_setup(struct cx18_stream *s)
{
    struct cx18 *cx = s->cx;
    int raw = cx18_raw_vbi(cx);
    u32 data[CX2341X_MBOX_MAX_DATA];
    int lines;

    if (cx->is_60hz) {
        cx->vbi.count = 12;
        cx->vbi.start[0] = 10;
        cx->vbi.start[1] = 273;
    } else {        /* PAL/SECAM */
        cx->vbi.count = 18;
        cx->vbi.start[0] = 6;
        cx->vbi.start[1] = 318;
    }

    /* setup VBI registers */
    if (raw)
        v4l2_subdev_call(cx->sd_av, vbi, s_raw_fmt, &cx->vbi.in.fmt.vbi);
    else
        v4l2_subdev_call(cx->sd_av, vbi, s_sliced_fmt, &cx->vbi.in.fmt.sliced);

    /*
     * Send the CX18_CPU_SET_RAW_VBI_PARAM API command to setup Encoder Raw
     * VBI when the first analog capture channel starts, as once it starts
     * (e.g. MPEG), we can't effect any change in the Encoder Raw VBI setup
     * (i.e. for the VBI capture channels).  We also send it for each
     * analog capture channel anyway just to make sure we get the proper
     * behavior
     */
    if (raw) {
        lines = cx->vbi.count * 2;
    } else {
        /*
         * For 525/60 systems, according to the VIP 2 & BT.656 std:
         * The EAV RP code's Field bit toggles on line 4, a few lines
         * after the Vertcal Blank bit has already toggled.
         * Tell the encoder to capture 21-4+1=18 lines per field,
         * since we want lines 10 through 21.
         *
         * For 625/50 systems, according to the VIP 2 & BT.656 std:
         * The EAV RP code's Field bit toggles on line 1, a few lines
         * after the Vertcal Blank bit has already toggled.
         * (We've actually set the digitizer so that the Field bit
         * toggles on line 2.) Tell the encoder to capture 23-2+1=22
         * lines per field, since we want lines 6 through 23.
         */
        lines = cx->is_60hz ? (21 - 4 + 1) * 2 : (23 - 2 + 1) * 2;
    }

    data[0] = s->handle;
    /* Lines per field */
    data[1] = (lines / 2) | ((lines / 2) << 16);
    /* bytes per line */
    data[2] = (raw ? vbi_active_samples
               : (cx->is_60hz ? vbi_hblank_samples_60Hz
                      : vbi_hblank_samples_50Hz));
    /* Every X number of frames a VBI interrupt arrives
       (frames as in 25 or 30 fps) */
    data[3] = 1;
    /*
     * Set the SAV/EAV RP codes to look for as start/stop points
     * when in VIP-1.1 mode
     */
    if (raw) {
        /*
         * Start codes for beginning of "active" line in vertical blank
         * 0x20 (               VerticalBlank                )
         * 0x60 (     EvenField VerticalBlank                )
         */
        data[4] = 0x20602060;
        /*
         * End codes for end of "active" raw lines and regular lines
         * 0x30 (               VerticalBlank HorizontalBlank)
         * 0x70 (     EvenField VerticalBlank HorizontalBlank)
         * 0x90 (Task                         HorizontalBlank)
         * 0xd0 (Task EvenField               HorizontalBlank)
         */
        data[5] = 0x307090d0;
    } else {
        /*
         * End codes for active video, we want data in the hblank region
         * 0xb0 (Task         0 VerticalBlank HorizontalBlank)
         * 0xf0 (Task EvenField VerticalBlank HorizontalBlank)
         *
         * Since the V bit is only allowed to toggle in the EAV RP code,
         * just before the first active region line, these two
         * are problematic:
         * 0x90 (Task                         HorizontalBlank)
         * 0xd0 (Task EvenField               HorizontalBlank)
         *
         * We have set the digitzer such that we don't have to worry
         * about these problem codes.
         */
        data[4] = 0xB0F0B0F0;
        /*
         * Start codes for beginning of active line in vertical blank
         * 0xa0 (Task           VerticalBlank                )
         * 0xe0 (Task EvenField VerticalBlank                )
         */
        data[5] = 0xA0E0A0E0;
    }

    CX18_DEBUG_INFO("Setup VBI h: %d lines %x bpl %d fr %d %x %x\n",
            data[0], data[1], data[2], data[3], data[4], data[5]);

    cx18_api(cx, CX18_CPU_SET_RAW_VBI_PARAM, 6, data);
}

void cx18_stream_rotate_idx_mdls(struct cx18 *cx)
{
    struct cx18_stream *s = &cx->streams[CX18_ENC_STREAM_TYPE_IDX];
    struct cx18_mdl *mdl;

    if (!cx18_stream_enabled(s))
        return;

    /* Return if the firmware is not running low on MDLs */
    if ((atomic_read(&s->q_free.depth) + atomic_read(&s->q_busy.depth)) >=
                        CX18_ENC_STREAM_TYPE_IDX_FW_MDL_MIN)
        return;

    /* Return if there are no MDLs to rotate back to the firmware */
    if (atomic_read(&s->q_full.depth) < 2)
        return;

    /*
     * Take the oldest IDX MDL still holding data, and discard its index
     * entries by scheduling the MDL to go back to the firmware
     */
    mdl = cx18_dequeue(s, &s->q_full);
    if (mdl != NULL)
        cx18_enqueue(s, mdl, &s->q_free);
}

static
struct cx18_queue *_cx18_stream_put_mdl_fw(struct cx18_stream *s,
                       struct cx18_mdl *mdl)
{
    struct cx18 *cx = s->cx;
    struct cx18_queue *q;

    /* Don't give it to the firmware, if we're not running a capture */
    if (s->handle == CX18_INVALID_TASK_HANDLE ||
        test_bit(CX18_F_S_STOPPING, &s->s_flags) ||
        !test_bit(CX18_F_S_STREAMING, &s->s_flags))
        return cx18_enqueue(s, mdl, &s->q_free);

    q = cx18_enqueue(s, mdl, &s->q_busy);
    if (q != &s->q_busy)
        return q; /* The firmware has the max MDLs it can handle */

    cx18_mdl_sync_for_device(s, mdl);
    cx18_vapi(cx, CX18_CPU_DE_SET_MDL, 5, s->handle,
          (void __iomem *) &cx->scb->cpu_mdl[mdl->id] - cx->enc_mem,
          s->bufs_per_mdl, mdl->id, s->mdl_size);
    return q;
}

static
void _cx18_stream_load_fw_queue(struct cx18_stream *s)
{
    struct cx18_queue *q;
    struct cx18_mdl *mdl;

    if (atomic_read(&s->q_free.depth) == 0 ||
        atomic_read(&s->q_busy.depth) >= CX18_MAX_FW_MDLS_PER_STREAM)
        return;

    /* Move from q_free to q_busy notifying the firmware, until the limit */
    do {
        mdl = cx18_dequeue(s, &s->q_free);
        if (mdl == NULL)
            break;
        q = _cx18_stream_put_mdl_fw(s, mdl);
    } while (atomic_read(&s->q_busy.depth) < CX18_MAX_FW_MDLS_PER_STREAM
         && q == &s->q_busy);
}

void cx18_out_work_handler(struct work_struct *work)
{
    struct cx18_stream *s =
             container_of(work, struct cx18_stream, out_work_order);

    _cx18_stream_load_fw_queue(s);
}

static void cx18_stream_configure_mdls(struct cx18_stream *s)
{
    cx18_unload_queues(s);

    switch (s->type) {
    case CX18_ENC_STREAM_TYPE_YUV:
        /*
         * Height should be a multiple of 32 lines.
         * Set the MDL size to the exact size needed for one frame.
         * Use enough buffers per MDL to cover the MDL size
         */
        if (s->pixelformat == V4L2_PIX_FMT_HM12)
            s->mdl_size = 720 * s->cx->cxhdl.height * 3 / 2;
        else
            s->mdl_size = 720 * s->cx->cxhdl.height * 2;
        s->bufs_per_mdl = s->mdl_size / s->buf_size;
        if (s->mdl_size % s->buf_size)
            s->bufs_per_mdl++;
        break;
    case CX18_ENC_STREAM_TYPE_VBI:
        s->bufs_per_mdl = 1;
        if  (cx18_raw_vbi(s->cx)) {
            s->mdl_size = (s->cx->is_60hz ? 12 : 18)
                               * 2 * vbi_active_samples;
        } else {
            /*
             * See comment in cx18_vbi_setup() below about the
             * extra lines we capture in sliced VBI mode due to
             * the lines on which EAV RP codes toggle.
            */
            s->mdl_size = s->cx->is_60hz
                   ? (21 - 4 + 1) * 2 * vbi_hblank_samples_60Hz
                   : (23 - 2 + 1) * 2 * vbi_hblank_samples_50Hz;
        }
        break;
    default:
        s->bufs_per_mdl = 1;
        s->mdl_size = s->buf_size * s->bufs_per_mdl;
        break;
    }

    cx18_load_queues(s);
}

int cx18_start_v4l2_encode_stream(struct cx18_stream *s)
{
    u32 data[MAX_MB_ARGUMENTS];
    struct cx18 *cx = s->cx;
    int captype = 0;
    struct cx18_stream *s_idx;

    if (!cx18_stream_enabled(s))
        return -EINVAL;

    CX18_DEBUG_INFO("Start encoder stream %s\n", s->name);

    switch (s->type) {
    case CX18_ENC_STREAM_TYPE_MPG:
        captype = CAPTURE_CHANNEL_TYPE_MPEG;
        cx->mpg_data_received = cx->vbi_data_inserted = 0;
        cx->dualwatch_jiffies = jiffies;
        cx->dualwatch_stereo_mode = v4l2_ctrl_g_ctrl(cx->cxhdl.audio_mode);
        cx->search_pack_header = 0;
        break;

    case CX18_ENC_STREAM_TYPE_IDX:
        captype = CAPTURE_CHANNEL_TYPE_INDEX;
        break;
    case CX18_ENC_STREAM_TYPE_TS:
        captype = CAPTURE_CHANNEL_TYPE_TS;
        break;
    case CX18_ENC_STREAM_TYPE_YUV:
        captype = CAPTURE_CHANNEL_TYPE_YUV;
        break;
    case CX18_ENC_STREAM_TYPE_PCM:
        captype = CAPTURE_CHANNEL_TYPE_PCM;
        break;
    case CX18_ENC_STREAM_TYPE_VBI:
#ifdef CX18_ENCODER_PARSES_SLICED
        captype = cx18_raw_vbi(cx) ?
             CAPTURE_CHANNEL_TYPE_VBI : CAPTURE_CHANNEL_TYPE_SLICED_VBI;
#else
        /*
         * Currently we set things up so that Sliced VBI from the
         * digitizer is handled as Raw VBI by the encoder
         */
        captype = CAPTURE_CHANNEL_TYPE_VBI;
#endif
        cx->vbi.frame = 0;
        cx->vbi.inserted_frame = 0;
        memset(cx->vbi.sliced_mpeg_size,
            0, sizeof(cx->vbi.sliced_mpeg_size));
        break;
    default:
        return -EINVAL;
    }

    /* Clear Streamoff flags in case left from last capture */
    clear_bit(CX18_F_S_STREAMOFF, &s->s_flags);

    cx18_vapi_result(cx, data, CX18_CREATE_TASK, 1, CPU_CMD_MASK_CAPTURE);
    s->handle = data[0];
    cx18_vapi(cx, CX18_CPU_SET_CHANNEL_TYPE, 2, s->handle, captype);

    /*
     * For everything but CAPTURE_CHANNEL_TYPE_TS, play it safe and
     * set up all the parameters, as it is not obvious which parameters the
     * firmware shares across capture channel types and which it does not.
     *
     * Some of the cx18_vapi() calls below apply to only certain capture
     * channel types.  We're hoping there's no harm in calling most of them
     * anyway, as long as the values are all consistent.  Setting some
     * shared parameters will have no effect once an analog capture channel
     * has started streaming.
     */
    if (captype != CAPTURE_CHANNEL_TYPE_TS) {
        cx18_vapi(cx, CX18_CPU_SET_VER_CROP_LINE, 2, s->handle, 0);
        cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 3, s->handle, 3, 1);
        cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 3, s->handle, 8, 0);
        cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 3, s->handle, 4, 1);

        /*
         * Audio related reset according to
         * Documentation/video4linux/cx2341x/fw-encoder-api.txt
         */
        if (atomic_read(&cx->ana_capturing) == 0)
            cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 2,
                  s->handle, 12);

        /*
         * Number of lines for Field 1 & Field 2 according to
         * Documentation/video4linux/cx2341x/fw-encoder-api.txt
         * Field 1 is 312 for 625 line systems in BT.656
         * Field 2 is 313 for 625 line systems in BT.656
         */
        cx18_vapi(cx, CX18_CPU_SET_CAPTURE_LINE_NO, 3,
              s->handle, 312, 313);

        if (cx->v4l2_cap & V4L2_CAP_VBI_CAPTURE)
            cx18_vbi_setup(s);

        /*
         * Select to receive I, P, and B frame index entries, if the
         * index stream is enabled.  Otherwise disable index entry
         * generation.
         */
        s_idx = &cx->streams[CX18_ENC_STREAM_TYPE_IDX];
        cx18_vapi_result(cx, data, CX18_CPU_SET_INDEXTABLE, 2,
                 s->handle, cx18_stream_enabled(s_idx) ? 7 : 0);

        /* Call out to the common CX2341x API setup for user controls */
        cx->cxhdl.priv = s;
        cx2341x_handler_setup(&cx->cxhdl);

        /*
         * When starting a capture and we're set for radio,
         * ensure the video is muted, despite the user control.
         */
        if (!cx->cxhdl.video_mute &&
            test_bit(CX18_F_I_RADIO_USER, &cx->i_flags))
            cx18_vapi(cx, CX18_CPU_SET_VIDEO_MUTE, 2, s->handle,
              (v4l2_ctrl_g_ctrl(cx->cxhdl.video_mute_yuv) << 8) | 1);

        /* Enable the Video Format Converter for UYVY 4:2:2 support,
         * rather than the default HM12 Macroblovk 4:2:0 support.
         */
        if (captype == CAPTURE_CHANNEL_TYPE_YUV) {
            if (s->pixelformat == V4L2_PIX_FMT_UYVY)
                cx18_vapi(cx, CX18_CPU_SET_VFC_PARAM, 2,
                    s->handle, 1);
            else
                /* If in doubt, default to HM12 */
                cx18_vapi(cx, CX18_CPU_SET_VFC_PARAM, 2,
                    s->handle, 0);
        }
    }

    if (atomic_read(&cx->tot_capturing) == 0) {
        cx2341x_handler_set_busy(&cx->cxhdl, 1);
        clear_bit(CX18_F_I_EOS, &cx->i_flags);
        cx18_write_reg(cx, 7, CX18_DSP0_INTERRUPT_MASK);
    }

    cx18_vapi(cx, CX18_CPU_DE_SET_MDL_ACK, 3, s->handle,
        (void __iomem *)&cx->scb->cpu_mdl_ack[s->type][0] - cx->enc_mem,
        (void __iomem *)&cx->scb->cpu_mdl_ack[s->type][1] - cx->enc_mem);

    /* Init all the cpu_mdls for this stream */
    cx18_stream_configure_mdls(s);
    _cx18_stream_load_fw_queue(s);

    /* begin_capture */
    if (cx18_vapi(cx, CX18_CPU_CAPTURE_START, 1, s->handle)) {
        CX18_DEBUG_WARN("Error starting capture!\n");
        /* Ensure we're really not capturing before releasing MDLs */
        set_bit(CX18_F_S_STOPPING, &s->s_flags);
        if (s->type == CX18_ENC_STREAM_TYPE_MPG)
            cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 2, s->handle, 1);
        else
            cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 1, s->handle);
        clear_bit(CX18_F_S_STREAMING, &s->s_flags);
        /* FIXME - CX18_F_S_STREAMOFF as well? */
        cx18_vapi(cx, CX18_CPU_DE_RELEASE_MDL, 1, s->handle);
        cx18_vapi(cx, CX18_DESTROY_TASK, 1, s->handle);
        s->handle = CX18_INVALID_TASK_HANDLE;
        clear_bit(CX18_F_S_STOPPING, &s->s_flags);
        if (atomic_read(&cx->tot_capturing) == 0) {
            set_bit(CX18_F_I_EOS, &cx->i_flags);
            cx18_write_reg(cx, 5, CX18_DSP0_INTERRUPT_MASK);
        }
        return -EINVAL;
    }

    /* you're live! sit back and await interrupts :) */
    if (captype != CAPTURE_CHANNEL_TYPE_TS)
        atomic_inc(&cx->ana_capturing);
    atomic_inc(&cx->tot_capturing);
    return 0;
}
EXPORT_SYMBOL(cx18_start_v4l2_encode_stream);

void cx18_stop_all_captures(struct cx18 *cx)
{
    int i;

    for (i = CX18_MAX_STREAMS - 1; i >= 0; i--) {
        struct cx18_stream *s = &cx->streams[i];

        if (!cx18_stream_enabled(s))
            continue;
        if (test_bit(CX18_F_S_STREAMING, &s->s_flags))
            cx18_stop_v4l2_encode_stream(s, 0);
    }
}

int cx18_stop_v4l2_encode_stream(struct cx18_stream *s, int gop_end)
{
    struct cx18 *cx = s->cx;

    if (!cx18_stream_enabled(s))
        return -EINVAL;

    /* This function assumes that you are allowed to stop the capture
       and that we are actually capturing */

    CX18_DEBUG_INFO("Stop Capture\n");

    if (atomic_read(&cx->tot_capturing) == 0)
        return 0;

    set_bit(CX18_F_S_STOPPING, &s->s_flags);
    if (s->type == CX18_ENC_STREAM_TYPE_MPG)
        cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 2, s->handle, !gop_end);
    else
        cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 1, s->handle);

    if (s->type == CX18_ENC_STREAM_TYPE_MPG && gop_end) {
        CX18_INFO("ignoring gop_end: not (yet?) supported by the firmware\n");
    }

    if (s->type != CX18_ENC_STREAM_TYPE_TS)
        atomic_dec(&cx->ana_capturing);
    atomic_dec(&cx->tot_capturing);

    /* Clear capture and no-read bits */
    clear_bit(CX18_F_S_STREAMING, &s->s_flags);

    /* Tell the CX23418 it can't use our buffers anymore */
    cx18_vapi(cx, CX18_CPU_DE_RELEASE_MDL, 1, s->handle);

    cx18_vapi(cx, CX18_DESTROY_TASK, 1, s->handle);
    s->handle = CX18_INVALID_TASK_HANDLE;
    clear_bit(CX18_F_S_STOPPING, &s->s_flags);

    if (atomic_read(&cx->tot_capturing) > 0)
        return 0;

    cx2341x_handler_set_busy(&cx->cxhdl, 0);
    cx18_write_reg(cx, 5, CX18_DSP0_INTERRUPT_MASK);
    wake_up(&s->waitq);

    return 0;
}
EXPORT_SYMBOL(cx18_stop_v4l2_encode_stream);

u32 cx18_find_handle(struct cx18 *cx)
{
    int i;

    /* find first available handle to be used for global settings */
    for (i = 0; i < CX18_MAX_STREAMS; i++) {
        struct cx18_stream *s = &cx->streams[i];

        if (s->video_dev && (s->handle != CX18_INVALID_TASK_HANDLE))
            return s->handle;
    }
    return CX18_INVALID_TASK_HANDLE;
}

struct cx18_stream *cx18_handle_to_stream(struct cx18 *cx, u32 handle)
{
    int i;
    struct cx18_stream *s;

    if (handle == CX18_INVALID_TASK_HANDLE)
        return NULL;

    for (i = 0; i < CX18_MAX_STREAMS; i++) {
        s = &cx->streams[i];
        if (s->handle != handle)
            continue;
        if (cx18_stream_enabled(s))
            return s;
    }
    return NULL;
}