sq905c.c

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/*
 * SQ905C subdriver
 *
 * Copyright (C) 2009 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
 */

/*
 *
 * This driver uses work done in
 * libgphoto2/camlibs/digigr8, Copyright (C) Theodore Kilgore.
 *
 * This driver has also used as a base the sq905c driver
 * and may contain code fragments from it.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#define MODULE_NAME "sq905c"

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

MODULE_AUTHOR("Theodore Kilgore <[email protected]>");
MODULE_DESCRIPTION("GSPCA/SQ905C USB Camera Driver");
MODULE_LICENSE("GPL");

/* Default timeouts, in ms */
#define SQ905C_CMD_TIMEOUT 500
#define SQ905C_DATA_TIMEOUT 1000

/* Maximum transfer size to use. */
#define SQ905C_MAX_TRANSFER 0x8000

#define FRAME_HEADER_LEN 0x50

/* Commands. These go in the "value" slot. */
#define SQ905C_CLEAR   0xa0     /* clear everything */
#define SQ905C_GET_ID  0x14f4       /* Read version number */
#define SQ905C_CAPTURE_LOW 0xa040   /* Starts capture at 160x120 */
#define SQ905C_CAPTURE_MED 0x1440   /* Starts capture at 320x240 */
#define SQ905C_CAPTURE_HI 0x2840    /* Starts capture at 320x240 */

/* For capture, this must go in the "index" slot. */
#define SQ905C_CAPTURE_INDEX 0x110f

/* Structure to hold all of our device specific stuff */
struct sd {
    struct gspca_dev gspca_dev; /* !! must be the first item */
    const struct v4l2_pix_format *cap_mode;
    /* Driver stuff */
    struct work_struct work_struct;
    struct workqueue_struct *work_thread;
};

/*
 * Most of these cameras will do 640x480 and 320x240. 160x120 works
 * in theory but gives very poor output. Therefore, not supported.
 * The 0x2770:0x9050 cameras have max resolution of 320x240.
 */
static struct v4l2_pix_format sq905c_mode[] = {
    { 320, 240, V4L2_PIX_FMT_SQ905C, V4L2_FIELD_NONE,
        .bytesperline = 320,
        .sizeimage = 320 * 240,
        .colorspace = V4L2_COLORSPACE_SRGB,
        .priv = 0},
    { 640, 480, V4L2_PIX_FMT_SQ905C, V4L2_FIELD_NONE,
        .bytesperline = 640,
        .sizeimage = 640 * 480,
        .colorspace = V4L2_COLORSPACE_SRGB,
        .priv = 0}
};

/* Send a command to the camera. */
static int sq905c_command(struct gspca_dev *gspca_dev, u16 command, u16 index)
{
    int ret;

    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,
                  command, index, NULL, 0,
                  SQ905C_CMD_TIMEOUT);
    if (ret < 0) {
        pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
        return ret;
    }

    return 0;
}

static int sq905c_read(struct gspca_dev *gspca_dev, u16 command, u16 index,
               int size)
{
    int ret;

    ret = usb_control_msg(gspca_dev->dev,
                  usb_rcvctrlpipe(gspca_dev->dev, 0),
                  USB_REQ_SYNCH_FRAME,      /* request */
                  USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                  command, index, gspca_dev->usb_buf, size,
                  SQ905C_CMD_TIMEOUT);
    if (ret < 0) {
        pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
        return ret;
    }

    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 sq905c_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 act_len;
    int packet_type;
    int ret;
    u8 *buffer;

    buffer = kmalloc(SQ905C_MAX_TRANSFER, GFP_KERNEL | GFP_DMA);
    if (!buffer) {
        pr_err("Couldn't allocate USB buffer\n");
        goto quit_stream;
    }

    while (gspca_dev->present && gspca_dev->streaming) {
#ifdef CONFIG_PM
        if (gspca_dev->frozen)
            break;
#endif
        /* Request the header, which tells the size to download */
        ret = usb_bulk_msg(gspca_dev->dev,
                usb_rcvbulkpipe(gspca_dev->dev, 0x81),
                buffer, FRAME_HEADER_LEN, &act_len,
                SQ905C_DATA_TIMEOUT);
        PDEBUG(D_STREAM,
            "Got %d bytes out of %d for header",
            act_len, FRAME_HEADER_LEN);
        if (ret < 0 || act_len < FRAME_HEADER_LEN)
            goto quit_stream;
        /* size is read from 4 bytes starting 0x40, little endian */
        bytes_left = buffer[0x40]|(buffer[0x41]<<8)|(buffer[0x42]<<16)
                    |(buffer[0x43]<<24);
        PDEBUG(D_STREAM, "bytes_left = 0x%x", bytes_left);
        /* We keep the header. It has other information, too. */
        packet_type = FIRST_PACKET;
        gspca_frame_add(gspca_dev, packet_type,
                buffer, FRAME_HEADER_LEN);
        while (bytes_left > 0 && gspca_dev->present) {
            data_len = bytes_left > SQ905C_MAX_TRANSFER ?
                SQ905C_MAX_TRANSFER : bytes_left;
            ret = usb_bulk_msg(gspca_dev->dev,
                usb_rcvbulkpipe(gspca_dev->dev, 0x81),
                buffer, data_len, &act_len,
                SQ905C_DATA_TIMEOUT);
            if (ret < 0 || act_len < data_len)
                goto quit_stream;
            PDEBUG(D_STREAM,
                "Got %d bytes out of %d for frame",
                data_len, bytes_left);
            bytes_left -= data_len;
            if (bytes_left == 0)
                packet_type = LAST_PACKET;
            else
                packet_type = INTER_PACKET;
            gspca_frame_add(gspca_dev, packet_type,
                    buffer, data_len);
        }
    }
quit_stream:
    if (gspca_dev->present) {
        mutex_lock(&gspca_dev->usb_lock);
        sq905c_command(gspca_dev, SQ905C_CLEAR, 0);
        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;
    int ret;

    PDEBUG(D_PROBE,
        "SQ9050 camera detected"
        " (vid/pid 0x%04X:0x%04X)", id->idVendor, id->idProduct);

    ret = sq905c_command(gspca_dev, SQ905C_GET_ID, 0);
    if (ret < 0) {
        PDEBUG(D_ERR, "Get version command failed");
        return ret;
    }

    ret = sq905c_read(gspca_dev, 0xf5, 0, 20);
    if (ret < 0) {
        PDEBUG(D_ERR, "Reading version command failed");
        return ret;
    }
    /* Note we leave out the usb id and the manufacturing date */
    PDEBUG(D_PROBE,
           "SQ9050 ID string: %02x - %*ph",
        gspca_dev->usb_buf[3], 6, gspca_dev->usb_buf + 14);

    cam->cam_mode = sq905c_mode;
    cam->nmodes = 2;
    if (gspca_dev->usb_buf[15] == 0)
        cam->nmodes = 1;
    /* We don't use the buffer gspca allocates so make it small. */
    cam->bulk_size = 32;
    cam->bulk = 1;
    INIT_WORK(&dev->work_struct, sq905c_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 sq905c_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)
{
    int ret;

    /* connect to the camera and reset it. */
    ret = sq905c_command(gspca_dev, SQ905C_CLEAR, 0);
    return ret;
}

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

    dev->cap_mode = gspca_dev->cam.cam_mode;
    /* "Open the shutter" and set size, to start capture */
    switch (gspca_dev->width) {
    case 640:
        PDEBUG(D_STREAM, "Start streaming at high resolution");
        dev->cap_mode++;
        ret = sq905c_command(gspca_dev, SQ905C_CAPTURE_HI,
                        SQ905C_CAPTURE_INDEX);
        break;
    default: /* 320 */
    PDEBUG(D_STREAM, "Start streaming at medium resolution");
        ret = sq905c_command(gspca_dev, SQ905C_CAPTURE_MED,
                        SQ905C_CAPTURE_INDEX);
    }

    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, 0x905c)},
    {USB_DEVICE(0x2770, 0x9050)},
    {USB_DEVICE(0x2770, 0x9051)},
    {USB_DEVICE(0x2770, 0x9052)},
    {USB_DEVICE(0x2770, 0x913d)},
    {}
};

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);