sq905.c

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/*
 * SQ905 subdriver
 *
 * Copyright (C) 2008, 2009 Adam Baker and Theodore Kilgore
 *
 * 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
 * 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
 */

/*
 * History and Acknowledgments
 *
 * The original Linux driver for SQ905 based cameras was written by
 * Marcell Lengyel and furter developed by many other contributors
 * and is available from http://sourceforge.net/projects/sqcam/
 *
 * This driver takes advantage of the reverse engineering work done for
 * that driver and for libgphoto2 but shares no code with them.
 *
 * This driver has used as a base the finepix driver and other gspca
 * based drivers and may still contain code fragments taken from those
 * drivers.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#define MODULE_NAME "sq905"

#include <linux/workqueue.h>
#include <linux/slab.h>
#include "gspca.h"

MODULE_AUTHOR("Adam Baker <[email protected]>, "
        "Theodore Kilgore <[email protected]>");
MODULE_DESCRIPTION("GSPCA/SQ905 USB Camera Driver");
MODULE_LICENSE("GPL");

/* Default timeouts, in ms */
#define SQ905_CMD_TIMEOUT 500
#define SQ905_DATA_TIMEOUT 1000

/* Maximum transfer size to use. */
#define SQ905_MAX_TRANSFER 0x8000
#define FRAME_HEADER_LEN 64

/* The known modes, or registers. These go in the "value" slot. */

/* 00 is "none" obviously */

#define SQ905_BULK_READ 0x03    /* precedes any bulk read */
#define SQ905_COMMAND   0x06    /* precedes the command codes below */
#define SQ905_PING  0x07    /* when reading an "idling" command */
#define SQ905_READ_DONE 0xc0    /* ack bulk read completed */

/* Any non-zero value in the bottom 2 bits of the 2nd byte of
 * the ID appears to indicate the camera can do 640*480. If the
 * LSB of that byte is set the image is just upside down, otherwise
 * it is rotated 180 degrees. */
#define SQ905_HIRES_MASK    0x00000300
#define SQ905_ORIENTATION_MASK  0x00000100

/* Some command codes. These go in the "index" slot. */

#define SQ905_ID      0xf0  /* asks for model string */
#define SQ905_CONFIG  0x20  /* gets photo alloc. table, not used here */
#define SQ905_DATA    0x30  /* accesses photo data, not used here */
#define SQ905_CLEAR   0xa0  /* clear everything */
#define SQ905_CAPTURE_LOW  0x60 /* Starts capture at 160x120 */
#define SQ905_CAPTURE_MED  0x61 /* Starts capture at 320x240 */
#define SQ905_CAPTURE_HIGH 0x62 /* Starts capture at 640x480 (some cams only) */
/* note that the capture command also controls the output dimensions */

/* Structure to hold all of our device specific stuff */
struct sd {
    struct gspca_dev gspca_dev; /* !! must be the first item */

    /*
     * Driver stuff
     */
    struct work_struct work_struct;
    struct workqueue_struct *work_thread;
};

static struct v4l2_pix_format sq905_mode[] = {
    { 160, 120, V4L2_PIX_FMT_SBGGR8, V4L2_FIELD_NONE,
        .bytesperline = 160,
        .sizeimage = 160 * 120,
        .colorspace = V4L2_COLORSPACE_SRGB,
        .priv = 0},
    { 320, 240, V4L2_PIX_FMT_SBGGR8, V4L2_FIELD_NONE,
        .bytesperline = 320,
        .sizeimage = 320 * 240,
        .colorspace = V4L2_COLORSPACE_SRGB,
        .priv = 0},
    { 640, 480, V4L2_PIX_FMT_SBGGR8, V4L2_FIELD_NONE,
        .bytesperline = 640,
        .sizeimage = 640 * 480,
        .colorspace = V4L2_COLORSPACE_SRGB,
        .priv = 0}
};

/*
 * Send a command to the camera.
 */
static int sq905_command(struct gspca_dev *gspca_dev, u16 index)
{
    int ret;

    gspca_dev->usb_buf[0] = '\0';
    ret = usb_control_msg(gspca_dev->dev,
                  usb_sndctrlpipe(gspca_dev->dev, 0),
                  USB_REQ_SYNCH_FRAME,                /* request */
                  USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                  SQ905_COMMAND, index, gspca_dev->usb_buf, 1,
                  SQ905_CMD_TIMEOUT);
    if (ret < 0) {
        pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
        return ret;
    }

    ret = usb_control_msg(gspca_dev->dev,
                  usb_sndctrlpipe(gspca_dev->dev, 0),
                  USB_REQ_SYNCH_FRAME,                /* request */
                  USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                  SQ905_PING, 0, gspca_dev->usb_buf, 1,
                  SQ905_CMD_TIMEOUT);
    if (ret < 0) {
        pr_err("%s: usb_control_msg failed 2 (%d)\n", __func__, ret);
        return ret;
    }

    return 0;
}

/*
 * Acknowledge the end of a frame - see warning on sq905_command.
 */
static int sq905_ack_frame(struct gspca_dev *gspca_dev)
{
    int ret;

    gspca_dev->usb_buf[0] = '\0';
    ret = usb_control_msg(gspca_dev->dev,
                  usb_sndctrlpipe(gspca_dev->dev, 0),
                  USB_REQ_SYNCH_FRAME,                /* request */
                  USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                  SQ905_READ_DONE, 0, gspca_dev->usb_buf, 1,
                  SQ905_CMD_TIMEOUT);
    if (ret < 0) {
        pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
        return ret;
    }

    return 0;
}

/*
 *  request and read a block of data - see warning on sq905_command.
 */
static int
sq905_read_data(struct gspca_dev *gspca_dev, u8 *data, int size, int need_lock)
{
    int ret;
    int act_len;

    gspca_dev->usb_buf[0] = '\0';
    if (need_lock)
        mutex_lock(&gspca_dev->usb_lock);
    ret = usb_control_msg(gspca_dev->dev,
                  usb_sndctrlpipe(gspca_dev->dev, 0),
                  USB_REQ_SYNCH_FRAME,                /* request */
                  USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                  SQ905_BULK_READ, size, gspca_dev->usb_buf,
                  1, SQ905_CMD_TIMEOUT);
    if (need_lock)
        mutex_unlock(&gspca_dev->usb_lock);
    if (ret < 0) {
        pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
        return ret;
    }
    ret = usb_bulk_msg(gspca_dev->dev,
               usb_rcvbulkpipe(gspca_dev->dev, 0x81),
               data, size, &act_len, SQ905_DATA_TIMEOUT);

    /* successful, it returns 0, otherwise  negative */
    if (ret < 0 || act_len != size) {
        pr_err("bulk read fail (%d) len %d/%d\n", ret, act_len, size);
        return -EIO;
    }
    return 0;
}

/*
 * This function is called as a workqueue function and runs whenever the camera
 * is streaming data. Because it is a workqueue function it is allowed to sleep
 * so we can use synchronous USB calls. To avoid possible collisions with other
 * threads attempting to use gspca_dev->usb_buf we take the usb_lock when
 * performing USB operations using it. In practice we don't really need this
 * as the camera doesn't provide any controls.
 */
static void sq905_dostream(struct work_struct *work)
{
    struct sd *dev = container_of(work, struct sd, work_struct);
    struct gspca_dev *gspca_dev = &dev->gspca_dev;
    int bytes_left; /* bytes remaining in current frame. */
    int data_len;   /* size to use for the next read. */
    int header_read; /* true if we have already read the frame header. */
    int packet_type;
    int frame_sz;
    int ret;
    u8 *data;
    u8 *buffer;

    buffer = kmalloc(SQ905_MAX_TRANSFER, GFP_KERNEL | GFP_DMA);
    if (!buffer) {
        pr_err("Couldn't allocate USB buffer\n");
        goto quit_stream;
    }

    frame_sz = gspca_dev->cam.cam_mode[gspca_dev->curr_mode].sizeimage
            + FRAME_HEADER_LEN;

    while (gspca_dev->present && gspca_dev->streaming) {
#ifdef CONFIG_PM
        if (gspca_dev->frozen)
            break;
#endif
        /* request some data and then read it until we have
         * a complete frame. */
        bytes_left = frame_sz;
        header_read = 0;

        /* Note we do not check for gspca_dev->streaming here, as
           we must finish reading an entire frame, otherwise the
           next time we stream we start reading in the middle of a
           frame. */
        while (bytes_left > 0 && gspca_dev->present) {
            data_len = bytes_left > SQ905_MAX_TRANSFER ?
                SQ905_MAX_TRANSFER : bytes_left;
            ret = sq905_read_data(gspca_dev, buffer, data_len, 1);
            if (ret < 0)
                goto quit_stream;
            PDEBUG(D_PACK,
                "Got %d bytes out of %d for frame",
                data_len, bytes_left);
            bytes_left -= data_len;
            data = buffer;
            if (!header_read) {
                packet_type = FIRST_PACKET;
                /* The first 64 bytes of each frame are
                 * a header full of FF 00 bytes */
                data += FRAME_HEADER_LEN;
                data_len -= FRAME_HEADER_LEN;
                header_read = 1;
            } else if (bytes_left == 0) {
                packet_type = LAST_PACKET;
            } else {
                packet_type = INTER_PACKET;
            }
            gspca_frame_add(gspca_dev, packet_type,
                    data, data_len);
            /* If entire frame fits in one packet we still
               need to add a LAST_PACKET */
            if (packet_type == FIRST_PACKET &&
                bytes_left == 0)
                gspca_frame_add(gspca_dev, LAST_PACKET,
                        NULL, 0);
        }
        if (gspca_dev->present) {
            /* acknowledge the frame */
            mutex_lock(&gspca_dev->usb_lock);
            ret = sq905_ack_frame(gspca_dev);
            mutex_unlock(&gspca_dev->usb_lock);
            if (ret < 0)
                goto quit_stream;
        }
    }
quit_stream:
    if (gspca_dev->present) {
        mutex_lock(&gspca_dev->usb_lock);
        sq905_command(gspca_dev, SQ905_CLEAR);
        mutex_unlock(&gspca_dev->usb_lock);
    }
    kfree(buffer);
}

/* This function is called at probe time just before sd_init */
static int sd_config(struct gspca_dev *gspca_dev,
        const struct usb_device_id *id)
{
    struct cam *cam = &gspca_dev->cam;
    struct sd *dev = (struct sd *) gspca_dev;

    /* We don't use the buffer gspca allocates so make it small. */
    cam->bulk = 1;
    cam->bulk_size = 64;

    INIT_WORK(&dev->work_struct, sq905_dostream);

    return 0;
}

/* called on streamoff with alt==0 and on disconnect */
/* the usb_lock is held at entry - restore on exit */
static void sd_stop0(struct gspca_dev *gspca_dev)
{
    struct sd *dev = (struct sd *) gspca_dev;

    /* wait for the work queue to terminate */
    mutex_unlock(&gspca_dev->usb_lock);
    /* This waits for sq905_dostream to finish */
    destroy_workqueue(dev->work_thread);
    dev->work_thread = NULL;
    mutex_lock(&gspca_dev->usb_lock);
}

/* this function is called at probe and resume time */
static int sd_init(struct gspca_dev *gspca_dev)
{
    u32 ident;
    int ret;

    /* connect to the camera and read
     * the model ID and process that and put it away.
     */
    ret = sq905_command(gspca_dev, SQ905_CLEAR);
    if (ret < 0)
        return ret;
    ret = sq905_command(gspca_dev, SQ905_ID);
    if (ret < 0)
        return ret;
    ret = sq905_read_data(gspca_dev, gspca_dev->usb_buf, 4, 0);
    if (ret < 0)
        return ret;
    /* usb_buf is allocated with kmalloc so is aligned.
     * Camera model number is the right way round if we assume this
     * reverse engineered ID is supposed to be big endian. */
    ident = be32_to_cpup((__be32 *)gspca_dev->usb_buf);
    ret = sq905_command(gspca_dev, SQ905_CLEAR);
    if (ret < 0)
        return ret;
    PDEBUG(D_CONF, "SQ905 camera ID %08x detected", ident);
    gspca_dev->cam.cam_mode = sq905_mode;
    gspca_dev->cam.nmodes = ARRAY_SIZE(sq905_mode);
    if (!(ident & SQ905_HIRES_MASK))
        gspca_dev->cam.nmodes--;

    if (ident & SQ905_ORIENTATION_MASK)
        gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP;
    else
        gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP |
                         V4L2_IN_ST_HFLIP;
    return 0;
}

/* Set up for getting frames. */
static int sd_start(struct gspca_dev *gspca_dev)
{
    struct sd *dev = (struct sd *) gspca_dev;
    int ret;

    /* "Open the shutter" and set size, to start capture */
    switch (gspca_dev->curr_mode) {
    default:
/*  case 2: */
        PDEBUG(D_STREAM, "Start streaming at high resolution");
        ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_HIGH);
        break;
    case 1:
        PDEBUG(D_STREAM, "Start streaming at medium resolution");
        ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_MED);
        break;
    case 0:
        PDEBUG(D_STREAM, "Start streaming at low resolution");
        ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_LOW);
    }

    if (ret < 0) {
        PDEBUG(D_ERR, "Start streaming command failed");
        return ret;
    }
    /* Start the workqueue function to do the streaming */
    dev->work_thread = create_singlethread_workqueue(MODULE_NAME);
    queue_work(dev->work_thread, &dev->work_struct);

    return 0;
}

/* Table of supported USB devices */
static const struct usb_device_id device_table[] = {
    {USB_DEVICE(0x2770, 0x9120)},
    {}
};

MODULE_DEVICE_TABLE(usb, device_table);

/* sub-driver description */
static const struct sd_desc sd_desc = {
    .name   = MODULE_NAME,
    .config = sd_config,
    .init   = sd_init,
    .start  = sd_start,
    .stop0  = sd_stop0,
};

/* -- device connect -- */
static int sd_probe(struct usb_interface *intf,
        const struct usb_device_id *id)
{
    return gspca_dev_probe(intf, id,
            &sd_desc,
            sizeof(struct sd),
            THIS_MODULE);
}

static struct usb_driver sd_driver = {
    .name       = MODULE_NAME,
    .id_table   = device_table,
    .probe      = sd_probe,
    .disconnect = gspca_disconnect,
#ifdef CONFIG_PM
    .suspend = gspca_suspend,
    .resume  = gspca_resume,
    .reset_resume = gspca_resume,
#endif
};

module_usb_driver(sd_driver);