// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Fujifilm Finepix subdriver
 *
 * Copyright (C) 2008 Frank Zago
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#define MODULE_NAME "finepix"

#include "gspca.h"

MODULE_AUTHOR("Frank Zago <frank@zago.net>");
MODULE_DESCRIPTION("Fujifilm FinePix USB V4L2 driver");
MODULE_LICENSE("GPL");

/* Default timeout, in ms */
#define FPIX_TIMEOUT 250

/* Maximum transfer size to use. The windows driver reads by chunks of
 * 0x2000 bytes, so do the same. Note: reading more seems to work
 * too. */
#define FPIX_MAX_TRANSFER 0x2000

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

        struct work_struct work_struct;
};

/* Delay after which claim the next frame. If the delay is too small,
 * the camera will return old frames. On the 4800Z, 20ms is bad, 25ms
 * will fail every 4 or 5 frames, but 30ms is perfect. On the A210,
 * 30ms is bad while 35ms is perfect. */
#define NEXT_FRAME_DELAY 35

/* These cameras only support 320x200. */
static const struct v4l2_pix_format fpix_mode[1] = {
        { 320, 240, V4L2_PIX_FMT_JPEG, V4L2_FIELD_NONE,
                .bytesperline = 320,
                .sizeimage = 320 * 240 * 3 / 8 + 590,
                .colorspace = V4L2_COLORSPACE_SRGB,
                .priv = 0}
};

/* send a command to the webcam */
static int command(struct gspca_dev *gspca_dev,
                int order)      /* 0: reset, 1: frame request */
{
        static u8 order_values[2][12] = {
                {0xc6, 0, 0, 0, 0, 0, 0,    0, 0x20, 0, 0, 0},  /* reset */
                {0xd3, 0, 0, 0, 0, 0, 0, 0x01,    0, 0, 0, 0},  /* fr req */
        };

        memcpy(gspca_dev->usb_buf, order_values[order], 12);
        return usb_control_msg(gspca_dev->dev,
                        usb_sndctrlpipe(gspca_dev->dev, 0),
                        USB_REQ_GET_STATUS,
                        USB_DIR_OUT | USB_TYPE_CLASS |
                        USB_RECIP_INTERFACE, 0, 0, gspca_dev->usb_buf,
                        12, FPIX_TIMEOUT);
}

/*
 * 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 dostream(struct work_struct *work)
{
        struct usb_fpix *dev = container_of(work, struct usb_fpix, work_struct);
        struct gspca_dev *gspca_dev = &dev->gspca_dev;
        struct urb *urb = gspca_dev->urb[0];
        u8 *data = urb->transfer_buffer;
        int ret = 0;
        int len;

        gspca_dbg(gspca_dev, D_STREAM, "dostream started\n");

        /* loop reading a frame */
again:
        while (gspca_dev->present && gspca_dev->streaming) {
#ifdef CONFIG_PM
                if (gspca_dev->frozen)
                        break;
#endif

                /* request a frame */
                mutex_lock(&gspca_dev->usb_lock);
                ret = command(gspca_dev, 1);
                mutex_unlock(&gspca_dev->usb_lock);
                if (ret < 0)
                        break;
#ifdef CONFIG_PM
                if (gspca_dev->frozen)
                        break;
#endif
                if (!gspca_dev->present || !gspca_dev->streaming)
                        break;

                /* the frame comes in parts */
                for (;;) {
                        ret = usb_bulk_msg(gspca_dev->dev,
                                        urb->pipe,
                                        data,
                                        FPIX_MAX_TRANSFER,
                                        &len, FPIX_TIMEOUT);
                        if (ret < 0) {
                                /* Most of the time we get a timeout
                                 * error. Just restart. */
                                goto again;
                        }
#ifdef CONFIG_PM
                        if (gspca_dev->frozen)
                                goto out;
#endif
                        if (!gspca_dev->present || !gspca_dev->streaming)
                                goto out;
                        if (len < FPIX_MAX_TRANSFER ||
                                (data[len - 2] == 0xff &&
                                        data[len - 1] == 0xd9)) {

                                /* If the result is less than what was asked
                                 * for, then it's the end of the
                                 * frame. Sometimes the jpeg is not complete,
                                 * but there's nothing we can do. We also end
                                 * here if the jpeg ends right at the end
                                 * of the frame. */
                                gspca_frame_add(gspca_dev, LAST_PACKET,
                                                data, len);
                                break;
                        }

                        /* got a partial image */
                        gspca_frame_add(gspca_dev,
                                        gspca_dev->last_packet_type
                                                == LAST_PACKET
                                        ? FIRST_PACKET : INTER_PACKET,
                                        data, len);
                }

                /* We must wait before trying reading the next
                 * frame. If we don't, or if the delay is too short,
                 * the camera will disconnect. */
                msleep(NEXT_FRAME_DELAY);
        }

out:
        gspca_dbg(gspca_dev, D_STREAM, "dostream stopped\n");
}

/* this function is called at probe time */
static int sd_config(struct gspca_dev *gspca_dev,
                const struct usb_device_id *id)
{
        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
        struct cam *cam = &gspca_dev->cam;

        cam->cam_mode = fpix_mode;
        cam->nmodes = 1;
        cam->bulk = 1;
        cam->bulk_size = FPIX_MAX_TRANSFER;

        INIT_WORK(&dev->work_struct, dostream);

        return 0;
}

/* this function is called at probe and resume time */
static int sd_init(struct gspca_dev *gspca_dev)
{
        return 0;
}

/* start the camera */
static int sd_start(struct gspca_dev *gspca_dev)
{
        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
        int ret, len;

        /* Init the device */
        ret = command(gspca_dev, 0);
        if (ret < 0) {
                pr_err("init failed %d\n", ret);
                return ret;
        }

        /* Read the result of the command. Ignore the result, for it
         * varies with the device. */
        ret = usb_bulk_msg(gspca_dev->dev,
                        gspca_dev->urb[0]->pipe,
                        gspca_dev->urb[0]->transfer_buffer,
                        FPIX_MAX_TRANSFER, &len,
                        FPIX_TIMEOUT);
        if (ret < 0) {
                pr_err("usb_bulk_msg failed %d\n", ret);
                return ret;
        }

        /* Request a frame, but don't read it */
        ret = command(gspca_dev, 1);
        if (ret < 0) {
                pr_err("frame request failed %d\n", ret);
                return ret;
        }

        /* Again, reset bulk in endpoint */
        usb_clear_halt(gspca_dev->dev, gspca_dev->urb[0]->pipe);

        schedule_work(&dev->work_struct);

        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 usb_fpix *dev = (struct usb_fpix *) gspca_dev;

        /* wait for the work queue to terminate */
        mutex_unlock(&gspca_dev->usb_lock);
        flush_work(&dev->work_struct);
        mutex_lock(&gspca_dev->usb_lock);
}

/* Table of supported USB devices */
static const struct usb_device_id device_table[] = {
        {USB_DEVICE(0x04cb, 0x0104)},
        {USB_DEVICE(0x04cb, 0x0109)},
        {USB_DEVICE(0x04cb, 0x010b)},
        {USB_DEVICE(0x04cb, 0x010f)},
        {USB_DEVICE(0x04cb, 0x0111)},
        {USB_DEVICE(0x04cb, 0x0113)},
        {USB_DEVICE(0x04cb, 0x0115)},
        {USB_DEVICE(0x04cb, 0x0117)},
        {USB_DEVICE(0x04cb, 0x0119)},
        {USB_DEVICE(0x04cb, 0x011b)},
        {USB_DEVICE(0x04cb, 0x011d)},
        {USB_DEVICE(0x04cb, 0x0121)},
        {USB_DEVICE(0x04cb, 0x0123)},
        {USB_DEVICE(0x04cb, 0x0125)},
        {USB_DEVICE(0x04cb, 0x0127)},
        {USB_DEVICE(0x04cb, 0x0129)},
        {USB_DEVICE(0x04cb, 0x012b)},
        {USB_DEVICE(0x04cb, 0x012d)},
        {USB_DEVICE(0x04cb, 0x012f)},
        {USB_DEVICE(0x04cb, 0x0131)},
        {USB_DEVICE(0x04cb, 0x013b)},
        {USB_DEVICE(0x04cb, 0x013d)},
        {USB_DEVICE(0x04cb, 0x013f)},
        {}
};

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 usb_fpix),
                        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);