// SPDX-License-Identifier: GPL-2.0-only
/*
 * Hauppauge HD PVR USB driver - video 4 linux 2 interface
 *
 * Copyright (C) 2008      Janne Grunau (j@jannau.net)
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>

#include <linux/videodev2.h>
#include <linux/v4l2-dv-timings.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-common.h>
#include <media/v4l2-dv-timings.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#include "hdpvr.h"

#define BULK_URB_TIMEOUT   90 /* 0.09 seconds */

#define print_buffer_status() { \
                v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,       \
                         "%s:%d buffer stat: %d free, %d proc\n",       \
                         __func__, __LINE__,                            \
                         list_size(&dev->free_buff_list),               \
                         list_size(&dev->rec_buff_list)); }

static const struct v4l2_dv_timings hdpvr_dv_timings[] = {
        V4L2_DV_BT_CEA_720X480I59_94,
        V4L2_DV_BT_CEA_720X576I50,
        V4L2_DV_BT_CEA_720X480P59_94,
        V4L2_DV_BT_CEA_720X576P50,
        V4L2_DV_BT_CEA_1280X720P50,
        V4L2_DV_BT_CEA_1280X720P60,
        V4L2_DV_BT_CEA_1920X1080I50,
        V4L2_DV_BT_CEA_1920X1080I60,
};

/* Use 480i59 as the default timings */
#define HDPVR_DEF_DV_TIMINGS_IDX (0)

struct hdpvr_fh {
        struct v4l2_fh fh;
        bool legacy_mode;
};

static inline struct hdpvr_fh *file_to_hdpvr_fh(struct file *file)
{
        return container_of(file_to_v4l2_fh(file), struct hdpvr_fh, fh);
}

static uint list_size(struct list_head *list)
{
        struct list_head *tmp;
        uint count = 0;

        list_for_each(tmp, list) {
                count++;
        }

        return count;
}

/*=========================================================================*/
/* urb callback */
static void hdpvr_read_bulk_callback(struct urb *urb)
{
        struct hdpvr_buffer *buf = (struct hdpvr_buffer *)urb->context;
        struct hdpvr_device *dev = buf->dev;

        /* marking buffer as received and wake waiting */
        buf->status = BUFSTAT_READY;
        wake_up_interruptible(&dev->wait_data);
}

/*=========================================================================*/
/* buffer bits */

/* function expects dev->io_mutex to be hold by caller */
int hdpvr_cancel_queue(struct hdpvr_device *dev)
{
        struct hdpvr_buffer *buf;

        list_for_each_entry(buf, &dev->rec_buff_list, buff_list) {
                usb_kill_urb(buf->urb);
                buf->status = BUFSTAT_AVAILABLE;
        }

        list_splice_init(&dev->rec_buff_list, dev->free_buff_list.prev);

        return 0;
}

static int hdpvr_free_queue(struct list_head *q)
{
        struct list_head *tmp;
        struct list_head *p;
        struct hdpvr_buffer *buf;
        struct urb *urb;

        for (p = q->next; p != q;) {
                buf = list_entry(p, struct hdpvr_buffer, buff_list);

                urb = buf->urb;
                usb_free_coherent(urb->dev, urb->transfer_buffer_length,
                                  urb->transfer_buffer, urb->transfer_dma);
                usb_free_urb(urb);
                tmp = p->next;
                list_del(p);
                kfree(buf);
                p = tmp;
        }

        return 0;
}

/* function expects dev->io_mutex to be hold by caller */
int hdpvr_free_buffers(struct hdpvr_device *dev)
{
        hdpvr_cancel_queue(dev);

        hdpvr_free_queue(&dev->free_buff_list);
        hdpvr_free_queue(&dev->rec_buff_list);

        return 0;
}

/* function expects dev->io_mutex to be hold by caller */
int hdpvr_alloc_buffers(struct hdpvr_device *dev, uint count)
{
        uint i;
        int retval = -ENOMEM;
        u8 *mem;
        struct hdpvr_buffer *buf;
        struct urb *urb;

        v4l2_dbg(MSG_INFO, hdpvr_debug, &dev->v4l2_dev,
                 "allocating %u buffers\n", count);

        for (i = 0; i < count; i++) {

                buf = kzalloc_obj(struct hdpvr_buffer);
                if (!buf) {
                        v4l2_err(&dev->v4l2_dev, "cannot allocate buffer\n");
                        goto exit;
                }
                buf->dev = dev;

                urb = usb_alloc_urb(0, GFP_KERNEL);
                if (!urb)
                        goto exit_urb;
                buf->urb = urb;

                mem = usb_alloc_coherent(dev->udev, dev->bulk_in_size, GFP_KERNEL,
                                         &urb->transfer_dma);
                if (!mem) {
                        v4l2_err(&dev->v4l2_dev,
                                 "cannot allocate usb transfer buffer\n");
                        goto exit_urb_buffer;
                }

                usb_fill_bulk_urb(buf->urb, dev->udev,
                                  usb_rcvbulkpipe(dev->udev,
                                                  dev->bulk_in_endpointAddr),
                                  mem, dev->bulk_in_size,
                                  hdpvr_read_bulk_callback, buf);

                buf->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
                buf->status = BUFSTAT_AVAILABLE;
                list_add_tail(&buf->buff_list, &dev->free_buff_list);
        }
        return 0;
exit_urb_buffer:
        usb_free_urb(urb);
exit_urb:
        kfree(buf);
exit:
        hdpvr_free_buffers(dev);
        return retval;
}

static int hdpvr_submit_buffers(struct hdpvr_device *dev)
{
        struct hdpvr_buffer *buf;
        struct urb *urb;
        int ret = 0, err_count = 0;

        mutex_lock(&dev->io_mutex);

        while (dev->status == STATUS_STREAMING &&
               !list_empty(&dev->free_buff_list)) {

                buf = list_entry(dev->free_buff_list.next, struct hdpvr_buffer,
                                 buff_list);
                if (buf->status != BUFSTAT_AVAILABLE) {
                        v4l2_err(&dev->v4l2_dev,
                                 "buffer not marked as available\n");
                        ret = -EFAULT;
                        goto err;
                }

                urb = buf->urb;
                urb->status = 0;
                urb->actual_length = 0;
                ret = usb_submit_urb(urb, GFP_KERNEL);
                if (ret) {
                        v4l2_err(&dev->v4l2_dev,
                                 "usb_submit_urb in %s returned %d\n",
                                 __func__, ret);
                        if (++err_count > 2)
                                break;
                        continue;
                }
                buf->status = BUFSTAT_INPROGRESS;
                list_move_tail(&buf->buff_list, &dev->rec_buff_list);
        }
err:
        print_buffer_status();
        mutex_unlock(&dev->io_mutex);
        return ret;
}

static struct hdpvr_buffer *hdpvr_get_next_buffer(struct hdpvr_device *dev)
{
        struct hdpvr_buffer *buf;

        mutex_lock(&dev->io_mutex);

        if (list_empty(&dev->rec_buff_list)) {
                mutex_unlock(&dev->io_mutex);
                return NULL;
        }

        buf = list_entry(dev->rec_buff_list.next, struct hdpvr_buffer,
                         buff_list);
        mutex_unlock(&dev->io_mutex);

        return buf;
}

static void hdpvr_transmit_buffers(struct work_struct *work)
{
        struct hdpvr_device *dev = container_of(work, struct hdpvr_device,
                                                worker);

        while (dev->status == STATUS_STREAMING) {

                if (hdpvr_submit_buffers(dev)) {
                        v4l2_err(&dev->v4l2_dev, "couldn't submit buffers\n");
                        goto error;
                }
                if (wait_event_interruptible(dev->wait_buffer,
                                !list_empty(&dev->free_buff_list) ||
                                             dev->status != STATUS_STREAMING))
                        goto error;
        }

        v4l2_dbg(MSG_INFO, hdpvr_debug, &dev->v4l2_dev,
                 "transmit worker exited\n");
        return;
error:
        v4l2_dbg(MSG_INFO, hdpvr_debug, &dev->v4l2_dev,
                 "transmit buffers errored\n");
        dev->status = STATUS_ERROR;
}

/* function expects dev->io_mutex to be hold by caller */
static int hdpvr_start_streaming(struct hdpvr_device *dev)
{
        int ret;
        struct hdpvr_video_info vidinf;

        if (dev->status == STATUS_STREAMING)
                return 0;
        if (dev->status != STATUS_IDLE)
                return -EAGAIN;

        ret = get_video_info(dev, &vidinf);
        if (ret < 0)
                return ret;

        if (!vidinf.valid) {
                msleep(250);
                v4l2_dbg(MSG_INFO, hdpvr_debug, &dev->v4l2_dev,
                                "no video signal at input %d\n", dev->options.video_input);
                return -EAGAIN;
        }

        v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
                        "video signal: %dx%d@%dhz\n", vidinf.width,
                        vidinf.height, vidinf.fps);

        /* start streaming 2 request */
        ret = usb_control_msg(dev->udev,
                        usb_sndctrlpipe(dev->udev, 0),
                        0xb8, 0x38, 0x1, 0, NULL, 0, 8000);
        v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
                        "encoder start control request returned %d\n", ret);
        if (ret < 0)
                return ret;

        ret = hdpvr_config_call(dev, CTRL_START_STREAMING_VALUE, 0x00);
        if (ret)
                return ret;

        dev->status = STATUS_STREAMING;

        schedule_work(&dev->worker);

        v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
                        "streaming started\n");

        return 0;
}


/* function expects dev->io_mutex to be hold by caller */
static int hdpvr_stop_streaming(struct hdpvr_device *dev)
{
        int actual_length;
        uint c = 0;
        u8 *buf;

        if (dev->status == STATUS_IDLE)
                return 0;
        else if (dev->status != STATUS_STREAMING)
                return -EAGAIN;

        buf = kmalloc(dev->bulk_in_size, GFP_KERNEL);
        if (!buf)
                v4l2_err(&dev->v4l2_dev, "failed to allocate temporary buffer for emptying the internal device buffer. Next capture start will be slow\n");

        dev->status = STATUS_SHUTTING_DOWN;
        hdpvr_config_call(dev, CTRL_STOP_STREAMING_VALUE, 0x00);
        mutex_unlock(&dev->io_mutex);

        wake_up_interruptible(&dev->wait_buffer);
        msleep(50);

        flush_work(&dev->worker);

        mutex_lock(&dev->io_mutex);
        /* kill the still outstanding urbs */
        hdpvr_cancel_queue(dev);

        /* emptying the device buffer beforeshutting it down */
        while (buf && ++c < 500 &&
               !usb_bulk_msg(dev->udev,
                             usb_rcvbulkpipe(dev->udev,
                                             dev->bulk_in_endpointAddr),
                             buf, dev->bulk_in_size, &actual_length,
                             BULK_URB_TIMEOUT)) {
                v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
                         "%2d: got %d bytes\n", c, actual_length);
        }
        kfree(buf);
        v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
                 "used %d urbs to empty device buffers\n", c-1);
        msleep(10);

        dev->status = STATUS_IDLE;

        return 0;
}


/*=======================================================================*/
/*
 * video 4 linux 2 file operations
 */

static int hdpvr_open(struct file *file)
{
        struct hdpvr_fh *fh = kzalloc_obj(*fh);

        if (fh == NULL)
                return -ENOMEM;
        fh->legacy_mode = true;
        v4l2_fh_init(&fh->fh, video_devdata(file));
        v4l2_fh_add(&fh->fh, file);
        return 0;
}

static int hdpvr_release(struct file *file)
{
        struct hdpvr_device *dev = video_drvdata(file);

        mutex_lock(&dev->io_mutex);
        if (file_to_v4l2_fh(file) == dev->owner) {
                hdpvr_stop_streaming(dev);
                dev->owner = NULL;
        }
        mutex_unlock(&dev->io_mutex);

        return v4l2_fh_release(file);
}

/*
 * hdpvr_v4l2_read()
 * will allocate buffers when called for the first time
 */
static ssize_t hdpvr_read(struct file *file, char __user *buffer, size_t count,
                          loff_t *pos)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_buffer *buf = NULL;
        struct urb *urb;
        int ret = 0;
        int rem, cnt;

        if (*pos)
                return -ESPIPE;

        mutex_lock(&dev->io_mutex);
        if (dev->status == STATUS_IDLE) {
                if (hdpvr_start_streaming(dev)) {
                        v4l2_dbg(MSG_INFO, hdpvr_debug, &dev->v4l2_dev,
                                 "start_streaming failed\n");
                        ret = -EIO;
                        msleep(200);
                        dev->status = STATUS_IDLE;
                        mutex_unlock(&dev->io_mutex);
                        goto err;
                }
                dev->owner = file_to_v4l2_fh(file);
                print_buffer_status();
        }
        mutex_unlock(&dev->io_mutex);

        /* wait for the first buffer */
        if (!(file->f_flags & O_NONBLOCK)) {
                if (wait_event_interruptible(dev->wait_data,
                                             !list_empty_careful(&dev->rec_buff_list)))
                        return -ERESTARTSYS;
        }

        buf = hdpvr_get_next_buffer(dev);

        while (count > 0 && buf) {

                if (buf->status != BUFSTAT_READY &&
                    dev->status != STATUS_DISCONNECTED) {
                        int err;
                        /* return nonblocking */
                        if (file->f_flags & O_NONBLOCK) {
                                if (!ret)
                                        ret = -EAGAIN;
                                goto err;
                        }

                        err = wait_event_interruptible_timeout(dev->wait_data,
                                buf->status == BUFSTAT_READY,
                                msecs_to_jiffies(1000));
                        if (err < 0) {
                                ret = err;
                                goto err;
                        }
                        if (!err) {
                                v4l2_info(&dev->v4l2_dev,
                                          "timeout: restart streaming\n");
                                mutex_lock(&dev->io_mutex);
                                hdpvr_stop_streaming(dev);
                                mutex_unlock(&dev->io_mutex);
                                /*
                                 * The FW needs about 4 seconds after streaming
                                 * stopped before it is ready to restart
                                 * streaming.
                                 */
                                msleep(4000);
                                err = hdpvr_start_streaming(dev);
                                if (err) {
                                        ret = err;
                                        goto err;
                                }
                        }
                }

                if (buf->status != BUFSTAT_READY)
                        break;

                /* set remaining bytes to copy */
                urb = buf->urb;
                rem = urb->actual_length - buf->pos;
                cnt = rem > count ? count : rem;

                if (copy_to_user(buffer, urb->transfer_buffer + buf->pos,
                                 cnt)) {
                        v4l2_err(&dev->v4l2_dev, "read: copy_to_user failed\n");
                        if (!ret)
                                ret = -EFAULT;
                        goto err;
                }

                buf->pos += cnt;
                count -= cnt;
                buffer += cnt;
                ret += cnt;

                /* finished, take next buffer */
                if (buf->pos == urb->actual_length) {
                        mutex_lock(&dev->io_mutex);
                        buf->pos = 0;
                        buf->status = BUFSTAT_AVAILABLE;

                        list_move_tail(&buf->buff_list, &dev->free_buff_list);

                        print_buffer_status();

                        mutex_unlock(&dev->io_mutex);

                        wake_up_interruptible(&dev->wait_buffer);

                        buf = hdpvr_get_next_buffer(dev);
                }
        }
err:
        if (!ret && !buf)
                ret = -EAGAIN;
        return ret;
}

static __poll_t hdpvr_poll(struct file *filp, poll_table *wait)
{
        __poll_t req_events = poll_requested_events(wait);
        struct hdpvr_buffer *buf = NULL;
        struct hdpvr_device *dev = video_drvdata(filp);
        __poll_t mask = v4l2_ctrl_poll(filp, wait);

        if (!(req_events & (EPOLLIN | EPOLLRDNORM)))
                return mask;

        mutex_lock(&dev->io_mutex);

        if (dev->status == STATUS_IDLE) {
                if (hdpvr_start_streaming(dev)) {
                        v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
                                 "start_streaming failed\n");
                        dev->status = STATUS_IDLE;
                } else {
                        dev->owner = file_to_v4l2_fh(filp);
                }

                print_buffer_status();
        }
        mutex_unlock(&dev->io_mutex);

        buf = hdpvr_get_next_buffer(dev);
        /* only wait if no data is available */
        if (!buf || buf->status != BUFSTAT_READY) {
                poll_wait(filp, &dev->wait_data, wait);
                buf = hdpvr_get_next_buffer(dev);
        }
        if (buf && buf->status == BUFSTAT_READY)
                mask |= EPOLLIN | EPOLLRDNORM;

        return mask;
}


static const struct v4l2_file_operations hdpvr_fops = {
        .owner          = THIS_MODULE,
        .open           = hdpvr_open,
        .release        = hdpvr_release,
        .read           = hdpvr_read,
        .poll           = hdpvr_poll,
        .unlocked_ioctl = video_ioctl2,
};

/*=======================================================================*/
/*
 * V4L2 ioctl handling
 */

static int vidioc_querycap(struct file *file, void  *priv,
                           struct v4l2_capability *cap)
{
        struct hdpvr_device *dev = video_drvdata(file);

        strscpy(cap->driver, "hdpvr", sizeof(cap->driver));
        strscpy(cap->card, "Hauppauge HD PVR", sizeof(cap->card));
        usb_make_path(dev->udev, cap->bus_info, sizeof(cap->bus_info));
        return 0;
}

static int vidioc_s_std(struct file *file, void *priv,
                        v4l2_std_id std)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);
        u8 std_type = 1;

        if (!fh->legacy_mode && dev->options.video_input == HDPVR_COMPONENT)
                return -ENODATA;
        if (dev->status != STATUS_IDLE)
                return -EBUSY;
        if (std & V4L2_STD_525_60)
                std_type = 0;
        dev->cur_std = std;
        dev->width = 720;
        dev->height = std_type ? 576 : 480;

        return hdpvr_config_call(dev, CTRL_VIDEO_STD_TYPE, std_type);
}

static int vidioc_g_std(struct file *file, void *priv,
                        v4l2_std_id *std)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);


        if (!fh->legacy_mode && dev->options.video_input == HDPVR_COMPONENT)
                return -ENODATA;
        *std = dev->cur_std;
        return 0;
}

static int vidioc_querystd(struct file *file, void *priv, v4l2_std_id *a)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);
        struct hdpvr_video_info vid_info;
        int ret;

        *a = V4L2_STD_UNKNOWN;
        if (dev->options.video_input == HDPVR_COMPONENT)
                return fh->legacy_mode ? 0 : -ENODATA;
        ret = get_video_info(dev, &vid_info);
        if (vid_info.valid && vid_info.width == 720 &&
            (vid_info.height == 480 || vid_info.height == 576)) {
                *a = (vid_info.height == 480) ?
                        V4L2_STD_525_60 : V4L2_STD_625_50;
        }
        return ret;
}

static int vidioc_s_dv_timings(struct file *file, void *priv,
                                    struct v4l2_dv_timings *timings)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);
        int i;

        fh->legacy_mode = false;
        if (dev->options.video_input)
                return -ENODATA;
        if (dev->status != STATUS_IDLE)
                return -EBUSY;
        for (i = 0; i < ARRAY_SIZE(hdpvr_dv_timings); i++)
                if (v4l2_match_dv_timings(timings, hdpvr_dv_timings + i, 0, false))
                        break;
        if (i == ARRAY_SIZE(hdpvr_dv_timings))
                return -EINVAL;
        dev->cur_dv_timings = hdpvr_dv_timings[i];
        dev->width = hdpvr_dv_timings[i].bt.width;
        dev->height = hdpvr_dv_timings[i].bt.height;
        return 0;
}

static int vidioc_g_dv_timings(struct file *file, void *priv,
                                    struct v4l2_dv_timings *timings)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);

        fh->legacy_mode = false;
        if (dev->options.video_input)
                return -ENODATA;
        *timings = dev->cur_dv_timings;
        return 0;
}

static int vidioc_query_dv_timings(struct file *file, void *priv,
                                    struct v4l2_dv_timings *timings)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);
        struct hdpvr_video_info vid_info;
        bool interlaced;
        int ret = 0;
        int i;

        fh->legacy_mode = false;
        if (dev->options.video_input)
                return -ENODATA;
        ret = get_video_info(dev, &vid_info);
        if (ret)
                return ret;
        if (!vid_info.valid)
                return -ENOLCK;
        interlaced = vid_info.fps <= 30;
        for (i = 0; i < ARRAY_SIZE(hdpvr_dv_timings); i++) {
                const struct v4l2_bt_timings *bt = &hdpvr_dv_timings[i].bt;
                unsigned hsize;
                unsigned vsize;
                unsigned fps;

                hsize = V4L2_DV_BT_FRAME_WIDTH(bt);
                vsize = V4L2_DV_BT_FRAME_HEIGHT(bt);
                fps = (unsigned)bt->pixelclock / (hsize * vsize);
                if (bt->width != vid_info.width ||
                    bt->height != vid_info.height ||
                    bt->interlaced != interlaced ||
                    (fps != vid_info.fps && fps + 1 != vid_info.fps))
                        continue;
                *timings = hdpvr_dv_timings[i];
                break;
        }
        if (i == ARRAY_SIZE(hdpvr_dv_timings))
                ret = -ERANGE;

        return ret;
}

static int vidioc_enum_dv_timings(struct file *file, void *priv,
                                    struct v4l2_enum_dv_timings *timings)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);

        fh->legacy_mode = false;
        memset(timings->reserved, 0, sizeof(timings->reserved));
        if (dev->options.video_input)
                return -ENODATA;
        if (timings->index >= ARRAY_SIZE(hdpvr_dv_timings))
                return -EINVAL;
        timings->timings = hdpvr_dv_timings[timings->index];
        return 0;
}

static int vidioc_dv_timings_cap(struct file *file, void *priv,
                                    struct v4l2_dv_timings_cap *cap)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);

        fh->legacy_mode = false;
        if (dev->options.video_input)
                return -ENODATA;
        cap->type = V4L2_DV_BT_656_1120;
        cap->bt.min_width = 720;
        cap->bt.max_width = 1920;
        cap->bt.min_height = 480;
        cap->bt.max_height = 1080;
        cap->bt.min_pixelclock = 27000000;
        cap->bt.max_pixelclock = 74250000;
        cap->bt.standards = V4L2_DV_BT_STD_CEA861;
        cap->bt.capabilities = V4L2_DV_BT_CAP_INTERLACED | V4L2_DV_BT_CAP_PROGRESSIVE;
        return 0;
}

static const char *iname[] = {
        [HDPVR_COMPONENT] = "Component",
        [HDPVR_SVIDEO]    = "S-Video",
        [HDPVR_COMPOSITE] = "Composite",
};

static int vidioc_enum_input(struct file *file, void *priv, struct v4l2_input *i)
{
        unsigned int n;

        n = i->index;
        if (n >= HDPVR_VIDEO_INPUTS)
                return -EINVAL;

        i->type = V4L2_INPUT_TYPE_CAMERA;

        strscpy(i->name, iname[n], sizeof(i->name));

        i->audioset = 1<<HDPVR_RCA_FRONT | 1<<HDPVR_RCA_BACK | 1<<HDPVR_SPDIF;

        i->capabilities = n ? V4L2_IN_CAP_STD : V4L2_IN_CAP_DV_TIMINGS;
        i->std = n ? V4L2_STD_ALL : 0;

        return 0;
}

static int vidioc_s_input(struct file *file, void *priv,
                          unsigned int index)
{
        struct hdpvr_device *dev = video_drvdata(file);
        int retval;

        if (index >= HDPVR_VIDEO_INPUTS)
                return -EINVAL;

        if (dev->status != STATUS_IDLE)
                return -EBUSY;

        retval = hdpvr_config_call(dev, CTRL_VIDEO_INPUT_VALUE, index+1);
        if (!retval) {
                dev->options.video_input = index;
                /*
                 * Unfortunately gstreamer calls ENUMSTD and bails out if it
                 * won't find any formats, even though component input is
                 * selected. This means that we have to leave tvnorms at
                 * V4L2_STD_ALL. We cannot use the 'legacy' trick since
                 * tvnorms is set at the device node level and not at the
                 * filehandle level.
                 *
                 * Comment this out for now, but if the legacy mode can be
                 * removed in the future, then this code should be enabled
                 * again.
                dev->video_dev.tvnorms =
                        (index != HDPVR_COMPONENT) ? V4L2_STD_ALL : 0;
                 */
        }

        return retval;
}

static int vidioc_g_input(struct file *file, void *priv,
                          unsigned int *index)
{
        struct hdpvr_device *dev = video_drvdata(file);

        *index = dev->options.video_input;
        return 0;
}


static const char *audio_iname[] = {
        [HDPVR_RCA_FRONT] = "RCA front",
        [HDPVR_RCA_BACK]  = "RCA back",
        [HDPVR_SPDIF]     = "SPDIF",
};

static int vidioc_enumaudio(struct file *file, void *priv,
                                struct v4l2_audio *audio)
{
        unsigned int n;

        n = audio->index;
        if (n >= HDPVR_AUDIO_INPUTS)
                return -EINVAL;

        audio->capability = V4L2_AUDCAP_STEREO;

        strscpy(audio->name, audio_iname[n], sizeof(audio->name));

        return 0;
}

static int vidioc_s_audio(struct file *file, void *priv,
                          const struct v4l2_audio *audio)
{
        struct hdpvr_device *dev = video_drvdata(file);
        int retval;

        if (audio->index >= HDPVR_AUDIO_INPUTS)
                return -EINVAL;

        if (dev->status != STATUS_IDLE)
                return -EBUSY;

        retval = hdpvr_set_audio(dev, audio->index+1, dev->options.audio_codec);
        if (!retval)
                dev->options.audio_input = audio->index;

        return retval;
}

static int vidioc_g_audio(struct file *file, void *priv,
                          struct v4l2_audio *audio)
{
        struct hdpvr_device *dev = video_drvdata(file);

        audio->index = dev->options.audio_input;
        audio->capability = V4L2_AUDCAP_STEREO;
        strscpy(audio->name, audio_iname[audio->index], sizeof(audio->name));
        return 0;
}

static int hdpvr_try_ctrl(struct v4l2_ctrl *ctrl)
{
        struct hdpvr_device *dev =
                container_of(ctrl->handler, struct hdpvr_device, hdl);

        switch (ctrl->id) {
        case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
                if (ctrl->val == V4L2_MPEG_VIDEO_BITRATE_MODE_VBR &&
                    dev->video_bitrate->val >= dev->video_bitrate_peak->val)
                        dev->video_bitrate_peak->val =
                                        dev->video_bitrate->val + 100000;
                break;
        }
        return 0;
}

static int hdpvr_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct hdpvr_device *dev =
                container_of(ctrl->handler, struct hdpvr_device, hdl);
        struct hdpvr_options *opt = &dev->options;
        int ret = -EINVAL;

        switch (ctrl->id) {
        case V4L2_CID_BRIGHTNESS:
                ret = hdpvr_config_call(dev, CTRL_BRIGHTNESS, ctrl->val);
                if (ret)
                        break;
                dev->options.brightness = ctrl->val;
                return 0;
        case V4L2_CID_CONTRAST:
                ret = hdpvr_config_call(dev, CTRL_CONTRAST, ctrl->val);
                if (ret)
                        break;
                dev->options.contrast = ctrl->val;
                return 0;
        case V4L2_CID_SATURATION:
                ret = hdpvr_config_call(dev, CTRL_SATURATION, ctrl->val);
                if (ret)
                        break;
                dev->options.saturation = ctrl->val;
                return 0;
        case V4L2_CID_HUE:
                ret = hdpvr_config_call(dev, CTRL_HUE, ctrl->val);
                if (ret)
                        break;
                dev->options.hue = ctrl->val;
                return 0;
        case V4L2_CID_SHARPNESS:
                ret = hdpvr_config_call(dev, CTRL_SHARPNESS, ctrl->val);
                if (ret)
                        break;
                dev->options.sharpness = ctrl->val;
                return 0;
        case V4L2_CID_MPEG_AUDIO_ENCODING:
                if (dev->flags & HDPVR_FLAG_AC3_CAP) {
                        opt->audio_codec = ctrl->val;
                        return hdpvr_set_audio(dev, opt->audio_input + 1,
                                              opt->audio_codec);
                }
                return 0;
        case V4L2_CID_MPEG_VIDEO_ENCODING:
                return 0;
/*      case V4L2_CID_MPEG_VIDEO_B_FRAMES: */
/*              if (ctrl->value == 0 && !(opt->gop_mode & 0x2)) { */
/*                      opt->gop_mode |= 0x2; */
/*                      hdpvr_config_call(dev, CTRL_GOP_MODE_VALUE, */
/*                                        opt->gop_mode); */
/*              } */
/*              if (ctrl->value == 128 && opt->gop_mode & 0x2) { */
/*                      opt->gop_mode &= ~0x2; */
/*                      hdpvr_config_call(dev, CTRL_GOP_MODE_VALUE, */
/*                                        opt->gop_mode); */
/*              } */
/*              break; */
        case V4L2_CID_MPEG_VIDEO_BITRATE_MODE: {
                uint peak_bitrate = dev->video_bitrate_peak->val / 100000;
                uint bitrate = dev->video_bitrate->val / 100000;

                if (ctrl->is_new) {
                        if (ctrl->val == V4L2_MPEG_VIDEO_BITRATE_MODE_CBR)
                                opt->bitrate_mode = HDPVR_CONSTANT;
                        else
                                opt->bitrate_mode = HDPVR_VARIABLE_AVERAGE;
                        hdpvr_config_call(dev, CTRL_BITRATE_MODE_VALUE,
                                          opt->bitrate_mode);
                        v4l2_ctrl_activate(dev->video_bitrate_peak,
                                ctrl->val != V4L2_MPEG_VIDEO_BITRATE_MODE_CBR);
                }

                if (dev->video_bitrate_peak->is_new ||
                    dev->video_bitrate->is_new) {
                        opt->bitrate = bitrate;
                        opt->peak_bitrate = peak_bitrate;
                        hdpvr_set_bitrate(dev);
                }
                return 0;
        }
        case V4L2_CID_MPEG_STREAM_TYPE:
                return 0;
        default:
                break;
        }
        return ret;
}

static int vidioc_enum_fmt_vid_cap(struct file *file, void *priv,
                                    struct v4l2_fmtdesc *f)
{
        if (f->index != 0)
                return -EINVAL;

        f->pixelformat = V4L2_PIX_FMT_MPEG;

        return 0;
}

static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
                                struct v4l2_format *f)
{
        struct hdpvr_device *dev = video_drvdata(file);
        struct hdpvr_fh *fh = file_to_hdpvr_fh(file);
        int ret;

        /*
         * The original driver would always returns the current detected
         * resolution as the format (and EFAULT if it couldn't be detected).
         * With the introduction of VIDIOC_QUERY_DV_TIMINGS there is now a
         * better way of doing this, but to stay compatible with existing
         * applications we assume legacy mode every time an application opens
         * the device. Only if one of the new DV_TIMINGS ioctls is called
         * will the filehandle go into 'normal' mode where g_fmt returns the
         * last set format.
         */
        if (fh->legacy_mode) {
                struct hdpvr_video_info vid_info;

                ret = get_video_info(dev, &vid_info);
                if (ret < 0)
                        return ret;
                if (!vid_info.valid)
                        return -EFAULT;
                f->fmt.pix.width = vid_info.width;
                f->fmt.pix.height = vid_info.height;
        } else {
                f->fmt.pix.width = dev->width;
                f->fmt.pix.height = dev->height;
        }
        f->fmt.pix.pixelformat  = V4L2_PIX_FMT_MPEG;
        f->fmt.pix.sizeimage    = dev->bulk_in_size;
        f->fmt.pix.bytesperline = 0;
        if (f->fmt.pix.width == 720) {
                /* SDTV formats */
                f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
                f->fmt.pix.field = V4L2_FIELD_INTERLACED;
        } else {
                /* HDTV formats */
                f->fmt.pix.colorspace = V4L2_COLORSPACE_REC709;
                f->fmt.pix.field = V4L2_FIELD_NONE;
        }
        return 0;
}

static int vidioc_encoder_cmd(struct file *filp, void *priv,
                               struct v4l2_encoder_cmd *a)
{
        struct hdpvr_device *dev = video_drvdata(filp);
        int res = 0;

        mutex_lock(&dev->io_mutex);
        a->flags = 0;

        switch (a->cmd) {
        case V4L2_ENC_CMD_START:
                if (dev->owner && file_to_v4l2_fh(filp) != dev->owner) {
                        res = -EBUSY;
                        break;
                }
                if (dev->status == STATUS_STREAMING)
                        break;
                res = hdpvr_start_streaming(dev);
                if (!res)
                        dev->owner = file_to_v4l2_fh(filp);
                else
                        dev->status = STATUS_IDLE;
                break;
        case V4L2_ENC_CMD_STOP:
                if (dev->owner && file_to_v4l2_fh(filp) != dev->owner) {
                        res = -EBUSY;
                        break;
                }
                if (dev->status == STATUS_IDLE)
                        break;
                res = hdpvr_stop_streaming(dev);
                if (!res)
                        dev->owner = NULL;
                break;
        default:
                v4l2_dbg(MSG_INFO, hdpvr_debug, &dev->v4l2_dev,
                         "Unsupported encoder cmd %d\n", a->cmd);
                res = -EINVAL;
                break;
        }

        mutex_unlock(&dev->io_mutex);
        return res;
}

static int vidioc_try_encoder_cmd(struct file *filp, void *priv,
                                        struct v4l2_encoder_cmd *a)
{
        a->flags = 0;
        switch (a->cmd) {
        case V4L2_ENC_CMD_START:
        case V4L2_ENC_CMD_STOP:
                return 0;
        default:
                return -EINVAL;
        }
}

static const struct v4l2_ioctl_ops hdpvr_ioctl_ops = {
        .vidioc_querycap        = vidioc_querycap,
        .vidioc_s_std           = vidioc_s_std,
        .vidioc_g_std           = vidioc_g_std,
        .vidioc_querystd        = vidioc_querystd,
        .vidioc_s_dv_timings    = vidioc_s_dv_timings,
        .vidioc_g_dv_timings    = vidioc_g_dv_timings,
        .vidioc_query_dv_timings= vidioc_query_dv_timings,
        .vidioc_enum_dv_timings = vidioc_enum_dv_timings,
        .vidioc_dv_timings_cap  = vidioc_dv_timings_cap,
        .vidioc_enum_input      = vidioc_enum_input,
        .vidioc_g_input         = vidioc_g_input,
        .vidioc_s_input         = vidioc_s_input,
        .vidioc_enumaudio       = vidioc_enumaudio,
        .vidioc_g_audio         = vidioc_g_audio,
        .vidioc_s_audio         = vidioc_s_audio,
        .vidioc_enum_fmt_vid_cap= vidioc_enum_fmt_vid_cap,
        .vidioc_g_fmt_vid_cap   = vidioc_g_fmt_vid_cap,
        .vidioc_s_fmt_vid_cap   = vidioc_g_fmt_vid_cap,
        .vidioc_try_fmt_vid_cap = vidioc_g_fmt_vid_cap,
        .vidioc_encoder_cmd     = vidioc_encoder_cmd,
        .vidioc_try_encoder_cmd = vidioc_try_encoder_cmd,
        .vidioc_log_status      = v4l2_ctrl_log_status,
        .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
        .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};

static void hdpvr_device_release(struct video_device *vdev)
{
        struct hdpvr_device *dev = video_get_drvdata(vdev);

        hdpvr_delete(dev);
        flush_work(&dev->worker);

        v4l2_device_unregister(&dev->v4l2_dev);
        v4l2_ctrl_handler_free(&dev->hdl);

        /* deregister I2C adapter */
#if IS_ENABLED(CONFIG_I2C)
        mutex_lock(&dev->i2c_mutex);
        i2c_del_adapter(&dev->i2c_adapter);
        mutex_unlock(&dev->i2c_mutex);
#endif /* CONFIG_I2C */

        kfree(dev->usbc_buf);
        kfree(dev);
}

static const struct video_device hdpvr_video_template = {
        .fops                   = &hdpvr_fops,
        .release                = hdpvr_device_release,
        .ioctl_ops              = &hdpvr_ioctl_ops,
        .tvnorms                = V4L2_STD_ALL,
        .device_caps            = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_AUDIO |
                                  V4L2_CAP_READWRITE,
};

static const struct v4l2_ctrl_ops hdpvr_ctrl_ops = {
        .try_ctrl = hdpvr_try_ctrl,
        .s_ctrl = hdpvr_s_ctrl,
};

int hdpvr_register_videodev(struct hdpvr_device *dev, struct device *parent,
                            int devnum)
{
        struct v4l2_ctrl_handler *hdl = &dev->hdl;
        bool ac3 = dev->flags & HDPVR_FLAG_AC3_CAP;
        int res;

        // initialize dev->worker
        INIT_WORK(&dev->worker, hdpvr_transmit_buffers);

        dev->cur_std = V4L2_STD_525_60;
        dev->width = 720;
        dev->height = 480;
        dev->cur_dv_timings = hdpvr_dv_timings[HDPVR_DEF_DV_TIMINGS_IDX];
        v4l2_ctrl_handler_init(hdl, 11);
        if (dev->fw_ver > 0x15) {
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_BRIGHTNESS, 0x0, 0xff, 1, 0x80);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_CONTRAST, 0x0, 0xff, 1, 0x40);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_SATURATION, 0x0, 0xff, 1, 0x40);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_HUE, 0x0, 0x1e, 1, 0xf);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_SHARPNESS, 0x0, 0xff, 1, 0x80);
        } else {
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_BRIGHTNESS, 0x0, 0xff, 1, 0x86);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_CONTRAST, 0x0, 0xff, 1, 0x80);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_SATURATION, 0x0, 0xff, 1, 0x80);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_HUE, 0x0, 0xff, 1, 0x80);
                v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                        V4L2_CID_SHARPNESS, 0x0, 0xff, 1, 0x80);
        }

        v4l2_ctrl_new_std_menu(hdl, &hdpvr_ctrl_ops,
                V4L2_CID_MPEG_STREAM_TYPE,
                V4L2_MPEG_STREAM_TYPE_MPEG2_TS,
                0x1, V4L2_MPEG_STREAM_TYPE_MPEG2_TS);
        v4l2_ctrl_new_std_menu(hdl, &hdpvr_ctrl_ops,
                V4L2_CID_MPEG_AUDIO_ENCODING,
                ac3 ? V4L2_MPEG_AUDIO_ENCODING_AC3 : V4L2_MPEG_AUDIO_ENCODING_AAC,
                0x7, ac3 ? dev->options.audio_codec : V4L2_MPEG_AUDIO_ENCODING_AAC);
        v4l2_ctrl_new_std_menu(hdl, &hdpvr_ctrl_ops,
                V4L2_CID_MPEG_VIDEO_ENCODING,
                V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC, 0x3,
                V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC);

        dev->video_mode = v4l2_ctrl_new_std_menu(hdl, &hdpvr_ctrl_ops,
                V4L2_CID_MPEG_VIDEO_BITRATE_MODE,
                V4L2_MPEG_VIDEO_BITRATE_MODE_CBR, 0,
                V4L2_MPEG_VIDEO_BITRATE_MODE_CBR);

        dev->video_bitrate = v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                V4L2_CID_MPEG_VIDEO_BITRATE,
                1000000, 13500000, 100000, 6500000);
        dev->video_bitrate_peak = v4l2_ctrl_new_std(hdl, &hdpvr_ctrl_ops,
                V4L2_CID_MPEG_VIDEO_BITRATE_PEAK,
                1100000, 20200000, 100000, 9000000);
        dev->v4l2_dev.ctrl_handler = hdl;
        if (hdl->error) {
                res = hdl->error;
                v4l2_err(&dev->v4l2_dev, "Could not register controls\n");
                goto error;
        }
        v4l2_ctrl_cluster(3, &dev->video_mode);
        res = v4l2_ctrl_handler_setup(hdl);
        if (res < 0) {
                v4l2_err(&dev->v4l2_dev, "Could not setup controls\n");
                goto error;
        }

        /* setup and register video device */
        dev->video_dev = hdpvr_video_template;
        strscpy(dev->video_dev.name, "Hauppauge HD PVR",
                sizeof(dev->video_dev.name));
        dev->video_dev.v4l2_dev = &dev->v4l2_dev;
        video_set_drvdata(&dev->video_dev, dev);

        res = video_register_device(&dev->video_dev, VFL_TYPE_VIDEO, devnum);
        if (res < 0) {
                v4l2_err(&dev->v4l2_dev, "video_device registration failed\n");
                goto error;
        }

        return 0;
error:
        v4l2_ctrl_handler_free(hdl);
        return res;
}