linux/linux-5.4.31/drivers/media/pci/solo6x10/solo6x10-v4l2.c

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2024-01-30 10:43:28 +00:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2010-2013 Bluecherry, LLC <http://www.bluecherrydvr.com>
*
* Original author:
* Ben Collins <bcollins@ubuntu.com>
*
* Additional work by:
* John Brooks <john.brooks@bluecherry.net>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-common.h>
#include <media/v4l2-event.h>
#include <media/videobuf2-v4l2.h>
#include <media/videobuf2-dma-contig.h>
#include "solo6x10.h"
#include "solo6x10-tw28.h"
/* Image size is two fields, SOLO_HW_BPL is one horizontal line in hardware */
#define SOLO_HW_BPL 2048
#define solo_vlines(__solo) (__solo->video_vsize * 2)
#define solo_image_size(__solo) (solo_bytesperline(__solo) * \
solo_vlines(__solo))
#define solo_bytesperline(__solo) (__solo->video_hsize * 2)
#define MIN_VID_BUFFERS 2
static inline void erase_on(struct solo_dev *solo_dev)
{
solo_reg_write(solo_dev, SOLO_VO_DISP_ERASE, SOLO_VO_DISP_ERASE_ON);
solo_dev->erasing = 1;
solo_dev->frame_blank = 0;
}
static inline int erase_off(struct solo_dev *solo_dev)
{
if (!solo_dev->erasing)
return 0;
/* First time around, assert erase off */
if (!solo_dev->frame_blank)
solo_reg_write(solo_dev, SOLO_VO_DISP_ERASE, 0);
/* Keep the erasing flag on for 8 frames minimum */
if (solo_dev->frame_blank++ >= 8)
solo_dev->erasing = 0;
return 1;
}
void solo_video_in_isr(struct solo_dev *solo_dev)
{
wake_up_interruptible_all(&solo_dev->disp_thread_wait);
}
static void solo_win_setup(struct solo_dev *solo_dev, u8 ch,
int sx, int sy, int ex, int ey, int scale)
{
if (ch >= solo_dev->nr_chans)
return;
/* Here, we just keep window/channel the same */
solo_reg_write(solo_dev, SOLO_VI_WIN_CTRL0(ch),
SOLO_VI_WIN_CHANNEL(ch) |
SOLO_VI_WIN_SX(sx) |
SOLO_VI_WIN_EX(ex) |
SOLO_VI_WIN_SCALE(scale));
solo_reg_write(solo_dev, SOLO_VI_WIN_CTRL1(ch),
SOLO_VI_WIN_SY(sy) |
SOLO_VI_WIN_EY(ey));
}
static int solo_v4l2_ch_ext_4up(struct solo_dev *solo_dev, u8 idx, int on)
{
u8 ch = idx * 4;
if (ch >= solo_dev->nr_chans)
return -EINVAL;
if (!on) {
u8 i;
for (i = ch; i < ch + 4; i++)
solo_win_setup(solo_dev, i, solo_dev->video_hsize,
solo_vlines(solo_dev),
solo_dev->video_hsize,
solo_vlines(solo_dev), 0);
return 0;
}
/* Row 1 */
solo_win_setup(solo_dev, ch, 0, 0, solo_dev->video_hsize / 2,
solo_vlines(solo_dev) / 2, 3);
solo_win_setup(solo_dev, ch + 1, solo_dev->video_hsize / 2, 0,
solo_dev->video_hsize, solo_vlines(solo_dev) / 2, 3);
/* Row 2 */
solo_win_setup(solo_dev, ch + 2, 0, solo_vlines(solo_dev) / 2,
solo_dev->video_hsize / 2, solo_vlines(solo_dev), 3);
solo_win_setup(solo_dev, ch + 3, solo_dev->video_hsize / 2,
solo_vlines(solo_dev) / 2, solo_dev->video_hsize,
solo_vlines(solo_dev), 3);
return 0;
}
static int solo_v4l2_ch_ext_16up(struct solo_dev *solo_dev, int on)
{
int sy, ysize, hsize, i;
if (!on) {
for (i = 0; i < 16; i++)
solo_win_setup(solo_dev, i, solo_dev->video_hsize,
solo_vlines(solo_dev),
solo_dev->video_hsize,
solo_vlines(solo_dev), 0);
return 0;
}
ysize = solo_vlines(solo_dev) / 4;
hsize = solo_dev->video_hsize / 4;
for (sy = 0, i = 0; i < 4; i++, sy += ysize) {
solo_win_setup(solo_dev, i * 4, 0, sy, hsize,
sy + ysize, 5);
solo_win_setup(solo_dev, (i * 4) + 1, hsize, sy,
hsize * 2, sy + ysize, 5);
solo_win_setup(solo_dev, (i * 4) + 2, hsize * 2, sy,
hsize * 3, sy + ysize, 5);
solo_win_setup(solo_dev, (i * 4) + 3, hsize * 3, sy,
solo_dev->video_hsize, sy + ysize, 5);
}
return 0;
}
static int solo_v4l2_ch(struct solo_dev *solo_dev, u8 ch, int on)
{
u8 ext_ch;
if (ch < solo_dev->nr_chans) {
solo_win_setup(solo_dev, ch, on ? 0 : solo_dev->video_hsize,
on ? 0 : solo_vlines(solo_dev),
solo_dev->video_hsize, solo_vlines(solo_dev),
on ? 1 : 0);
return 0;
}
if (ch >= solo_dev->nr_chans + solo_dev->nr_ext)
return -EINVAL;
ext_ch = ch - solo_dev->nr_chans;
/* 4up's first */
if (ext_ch < 4)
return solo_v4l2_ch_ext_4up(solo_dev, ext_ch, on);
/* Remaining case is 16up for 16-port */
return solo_v4l2_ch_ext_16up(solo_dev, on);
}
static int solo_v4l2_set_ch(struct solo_dev *solo_dev, u8 ch)
{
if (ch >= solo_dev->nr_chans + solo_dev->nr_ext)
return -EINVAL;
erase_on(solo_dev);
solo_v4l2_ch(solo_dev, solo_dev->cur_disp_ch, 0);
solo_v4l2_ch(solo_dev, ch, 1);
solo_dev->cur_disp_ch = ch;
return 0;
}
static void solo_fillbuf(struct solo_dev *solo_dev,
struct vb2_buffer *vb)
{
struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
dma_addr_t addr;
unsigned int fdma_addr;
int error = -1;
int i;
addr = vb2_dma_contig_plane_dma_addr(vb, 0);
if (!addr)
goto finish_buf;
if (erase_off(solo_dev)) {
void *p = vb2_plane_vaddr(vb, 0);
int image_size = solo_image_size(solo_dev);
for (i = 0; i < image_size; i += 2) {
((u8 *)p)[i] = 0x80;
((u8 *)p)[i + 1] = 0x00;
}
error = 0;
} else {
fdma_addr = SOLO_DISP_EXT_ADDR + (solo_dev->old_write *
(SOLO_HW_BPL * solo_vlines(solo_dev)));
error = solo_p2m_dma_t(solo_dev, 0, addr, fdma_addr,
solo_bytesperline(solo_dev),
solo_vlines(solo_dev), SOLO_HW_BPL);
}
finish_buf:
if (!error) {
vb2_set_plane_payload(vb, 0,
solo_vlines(solo_dev) * solo_bytesperline(solo_dev));
vbuf->sequence = solo_dev->sequence++;
vb->timestamp = ktime_get_ns();
}
vb2_buffer_done(vb, error ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
}
static void solo_thread_try(struct solo_dev *solo_dev)
{
struct solo_vb2_buf *vb;
/* Only "break" from this loop if slock is held, otherwise
* just return. */
for (;;) {
unsigned int cur_write;
cur_write = SOLO_VI_STATUS0_PAGE(
solo_reg_read(solo_dev, SOLO_VI_STATUS0));
if (cur_write == solo_dev->old_write)
return;
spin_lock(&solo_dev->slock);
if (list_empty(&solo_dev->vidq_active))
break;
vb = list_first_entry(&solo_dev->vidq_active, struct solo_vb2_buf,
list);
solo_dev->old_write = cur_write;
list_del(&vb->list);
spin_unlock(&solo_dev->slock);
solo_fillbuf(solo_dev, &vb->vb.vb2_buf);
}
assert_spin_locked(&solo_dev->slock);
spin_unlock(&solo_dev->slock);
}
static int solo_thread(void *data)
{
struct solo_dev *solo_dev = data;
DECLARE_WAITQUEUE(wait, current);
set_freezable();
add_wait_queue(&solo_dev->disp_thread_wait, &wait);
for (;;) {
long timeout = schedule_timeout_interruptible(HZ);
if (timeout == -ERESTARTSYS || kthread_should_stop())
break;
solo_thread_try(solo_dev);
try_to_freeze();
}
remove_wait_queue(&solo_dev->disp_thread_wait, &wait);
return 0;
}
static int solo_start_thread(struct solo_dev *solo_dev)
{
int ret = 0;
solo_dev->kthread = kthread_run(solo_thread, solo_dev, SOLO6X10_NAME "_disp");
if (IS_ERR(solo_dev->kthread)) {
ret = PTR_ERR(solo_dev->kthread);
solo_dev->kthread = NULL;
return ret;
}
solo_irq_on(solo_dev, SOLO_IRQ_VIDEO_IN);
return ret;
}
static void solo_stop_thread(struct solo_dev *solo_dev)
{
if (!solo_dev->kthread)
return;
solo_irq_off(solo_dev, SOLO_IRQ_VIDEO_IN);
kthread_stop(solo_dev->kthread);
solo_dev->kthread = NULL;
}
static int solo_queue_setup(struct vb2_queue *q,
unsigned int *num_buffers, unsigned int *num_planes,
unsigned int sizes[], struct device *alloc_devs[])
{
struct solo_dev *solo_dev = vb2_get_drv_priv(q);
sizes[0] = solo_image_size(solo_dev);
*num_planes = 1;
if (*num_buffers < MIN_VID_BUFFERS)
*num_buffers = MIN_VID_BUFFERS;
return 0;
}
static int solo_start_streaming(struct vb2_queue *q, unsigned int count)
{
struct solo_dev *solo_dev = vb2_get_drv_priv(q);
solo_dev->sequence = 0;
return solo_start_thread(solo_dev);
}
static void solo_stop_streaming(struct vb2_queue *q)
{
struct solo_dev *solo_dev = vb2_get_drv_priv(q);
solo_stop_thread(solo_dev);
spin_lock(&solo_dev->slock);
while (!list_empty(&solo_dev->vidq_active)) {
struct solo_vb2_buf *buf = list_entry(
solo_dev->vidq_active.next,
struct solo_vb2_buf, list);
list_del(&buf->list);
vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
}
spin_unlock(&solo_dev->slock);
INIT_LIST_HEAD(&solo_dev->vidq_active);
}
static void solo_buf_queue(struct vb2_buffer *vb)
{
struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
struct vb2_queue *vq = vb->vb2_queue;
struct solo_dev *solo_dev = vb2_get_drv_priv(vq);
struct solo_vb2_buf *solo_vb =
container_of(vbuf, struct solo_vb2_buf, vb);
spin_lock(&solo_dev->slock);
list_add_tail(&solo_vb->list, &solo_dev->vidq_active);
spin_unlock(&solo_dev->slock);
wake_up_interruptible(&solo_dev->disp_thread_wait);
}
static const struct vb2_ops solo_video_qops = {
.queue_setup = solo_queue_setup,
.buf_queue = solo_buf_queue,
.start_streaming = solo_start_streaming,
.stop_streaming = solo_stop_streaming,
.wait_prepare = vb2_ops_wait_prepare,
.wait_finish = vb2_ops_wait_finish,
};
static int solo_querycap(struct file *file, void *priv,
struct v4l2_capability *cap)
{
struct solo_dev *solo_dev = video_drvdata(file);
strscpy(cap->driver, SOLO6X10_NAME, sizeof(cap->driver));
strscpy(cap->card, "Softlogic 6x10", sizeof(cap->card));
snprintf(cap->bus_info, sizeof(cap->bus_info), "PCI:%s",
pci_name(solo_dev->pdev));
return 0;
}
static int solo_enum_ext_input(struct solo_dev *solo_dev,
struct v4l2_input *input)
{
int ext = input->index - solo_dev->nr_chans;
unsigned int nup, first;
if (ext >= solo_dev->nr_ext)
return -EINVAL;
nup = (ext == 4) ? 16 : 4;
first = (ext & 3) << 2; /* first channel in the n-up */
snprintf(input->name, sizeof(input->name),
"Multi %d-up (cameras %d-%d)",
nup, first + 1, first + nup);
/* Possible outputs:
* Multi 4-up (cameras 1-4)
* Multi 4-up (cameras 5-8)
* Multi 4-up (cameras 9-12)
* Multi 4-up (cameras 13-16)
* Multi 16-up (cameras 1-16)
*/
return 0;
}
static int solo_enum_input(struct file *file, void *priv,
struct v4l2_input *input)
{
struct solo_dev *solo_dev = video_drvdata(file);
if (input->index >= solo_dev->nr_chans) {
int ret = solo_enum_ext_input(solo_dev, input);
if (ret < 0)
return ret;
} else {
snprintf(input->name, sizeof(input->name), "Camera %d",
input->index + 1);
/* We can only check this for normal inputs */
if (!tw28_get_video_status(solo_dev, input->index))
input->status = V4L2_IN_ST_NO_SIGNAL;
}
input->type = V4L2_INPUT_TYPE_CAMERA;
input->std = solo_dev->vfd->tvnorms;
return 0;
}
static int solo_set_input(struct file *file, void *priv, unsigned int index)
{
struct solo_dev *solo_dev = video_drvdata(file);
int ret = solo_v4l2_set_ch(solo_dev, index);
if (!ret) {
while (erase_off(solo_dev))
/* Do nothing */;
}
return ret;
}
static int solo_get_input(struct file *file, void *priv, unsigned int *index)
{
struct solo_dev *solo_dev = video_drvdata(file);
*index = solo_dev->cur_disp_ch;
return 0;
}
static int solo_enum_fmt_cap(struct file *file, void *priv,
struct v4l2_fmtdesc *f)
{
if (f->index)
return -EINVAL;
f->pixelformat = V4L2_PIX_FMT_UYVY;
return 0;
}
static int solo_try_fmt_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct solo_dev *solo_dev = video_drvdata(file);
struct v4l2_pix_format *pix = &f->fmt.pix;
int image_size = solo_image_size(solo_dev);
if (pix->pixelformat != V4L2_PIX_FMT_UYVY)
return -EINVAL;
pix->width = solo_dev->video_hsize;
pix->height = solo_vlines(solo_dev);
pix->sizeimage = image_size;
pix->field = V4L2_FIELD_INTERLACED;
pix->pixelformat = V4L2_PIX_FMT_UYVY;
pix->colorspace = V4L2_COLORSPACE_SMPTE170M;
return 0;
}
static int solo_set_fmt_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct solo_dev *solo_dev = video_drvdata(file);
if (vb2_is_busy(&solo_dev->vidq))
return -EBUSY;
/* For right now, if it doesn't match our running config,
* then fail */
return solo_try_fmt_cap(file, priv, f);
}
static int solo_get_fmt_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct solo_dev *solo_dev = video_drvdata(file);
struct v4l2_pix_format *pix = &f->fmt.pix;
pix->width = solo_dev->video_hsize;
pix->height = solo_vlines(solo_dev);
pix->pixelformat = V4L2_PIX_FMT_UYVY;
pix->field = V4L2_FIELD_INTERLACED;
pix->sizeimage = solo_image_size(solo_dev);
pix->colorspace = V4L2_COLORSPACE_SMPTE170M;
pix->bytesperline = solo_bytesperline(solo_dev);
return 0;
}
static int solo_g_std(struct file *file, void *priv, v4l2_std_id *i)
{
struct solo_dev *solo_dev = video_drvdata(file);
if (solo_dev->video_type == SOLO_VO_FMT_TYPE_NTSC)
*i = V4L2_STD_NTSC_M;
else
*i = V4L2_STD_PAL;
return 0;
}
int solo_set_video_type(struct solo_dev *solo_dev, bool is_50hz)
{
int i;
/* Make sure all video nodes are idle */
if (vb2_is_busy(&solo_dev->vidq))
return -EBUSY;
for (i = 0; i < solo_dev->nr_chans; i++)
if (vb2_is_busy(&solo_dev->v4l2_enc[i]->vidq))
return -EBUSY;
solo_dev->video_type = is_50hz ? SOLO_VO_FMT_TYPE_PAL :
SOLO_VO_FMT_TYPE_NTSC;
/* Reconfigure for the new standard */
solo_disp_init(solo_dev);
solo_enc_init(solo_dev);
solo_tw28_init(solo_dev);
for (i = 0; i < solo_dev->nr_chans; i++)
solo_update_mode(solo_dev->v4l2_enc[i]);
return solo_v4l2_set_ch(solo_dev, solo_dev->cur_disp_ch);
}
static int solo_s_std(struct file *file, void *priv, v4l2_std_id std)
{
struct solo_dev *solo_dev = video_drvdata(file);
return solo_set_video_type(solo_dev, std & V4L2_STD_625_50);
}
static int solo_s_ctrl(struct v4l2_ctrl *ctrl)
{
struct solo_dev *solo_dev =
container_of(ctrl->handler, struct solo_dev, disp_hdl);
switch (ctrl->id) {
case V4L2_CID_MOTION_TRACE:
if (ctrl->val) {
solo_reg_write(solo_dev, SOLO_VI_MOTION_BORDER,
SOLO_VI_MOTION_Y_ADD |
SOLO_VI_MOTION_Y_VALUE(0x20) |
SOLO_VI_MOTION_CB_VALUE(0x10) |
SOLO_VI_MOTION_CR_VALUE(0x10));
solo_reg_write(solo_dev, SOLO_VI_MOTION_BAR,
SOLO_VI_MOTION_CR_ADD |
SOLO_VI_MOTION_Y_VALUE(0x10) |
SOLO_VI_MOTION_CB_VALUE(0x80) |
SOLO_VI_MOTION_CR_VALUE(0x10));
} else {
solo_reg_write(solo_dev, SOLO_VI_MOTION_BORDER, 0);
solo_reg_write(solo_dev, SOLO_VI_MOTION_BAR, 0);
}
return 0;
default:
break;
}
return -EINVAL;
}
static const struct v4l2_file_operations solo_v4l2_fops = {
.owner = THIS_MODULE,
.open = v4l2_fh_open,
.release = vb2_fop_release,
.read = vb2_fop_read,
.poll = vb2_fop_poll,
.mmap = vb2_fop_mmap,
.unlocked_ioctl = video_ioctl2,
};
static const struct v4l2_ioctl_ops solo_v4l2_ioctl_ops = {
.vidioc_querycap = solo_querycap,
.vidioc_s_std = solo_s_std,
.vidioc_g_std = solo_g_std,
/* Input callbacks */
.vidioc_enum_input = solo_enum_input,
.vidioc_s_input = solo_set_input,
.vidioc_g_input = solo_get_input,
/* Video capture format callbacks */
.vidioc_enum_fmt_vid_cap = solo_enum_fmt_cap,
.vidioc_try_fmt_vid_cap = solo_try_fmt_cap,
.vidioc_s_fmt_vid_cap = solo_set_fmt_cap,
.vidioc_g_fmt_vid_cap = solo_get_fmt_cap,
/* Streaming I/O */
.vidioc_reqbufs = vb2_ioctl_reqbufs,
.vidioc_querybuf = vb2_ioctl_querybuf,
.vidioc_qbuf = vb2_ioctl_qbuf,
.vidioc_dqbuf = vb2_ioctl_dqbuf,
.vidioc_streamon = vb2_ioctl_streamon,
.vidioc_streamoff = vb2_ioctl_streamoff,
/* Logging and events */
.vidioc_log_status = v4l2_ctrl_log_status,
.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};
static const struct video_device solo_v4l2_template = {
.name = SOLO6X10_NAME,
.fops = &solo_v4l2_fops,
.ioctl_ops = &solo_v4l2_ioctl_ops,
.minor = -1,
.release = video_device_release,
.tvnorms = V4L2_STD_NTSC_M | V4L2_STD_PAL,
.device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE |
V4L2_CAP_STREAMING,
};
static const struct v4l2_ctrl_ops solo_ctrl_ops = {
.s_ctrl = solo_s_ctrl,
};
static const struct v4l2_ctrl_config solo_motion_trace_ctrl = {
.ops = &solo_ctrl_ops,
.id = V4L2_CID_MOTION_TRACE,
.name = "Motion Detection Trace",
.type = V4L2_CTRL_TYPE_BOOLEAN,
.max = 1,
.step = 1,
};
int solo_v4l2_init(struct solo_dev *solo_dev, unsigned nr)
{
int ret;
int i;
init_waitqueue_head(&solo_dev->disp_thread_wait);
spin_lock_init(&solo_dev->slock);
mutex_init(&solo_dev->lock);
INIT_LIST_HEAD(&solo_dev->vidq_active);
solo_dev->vfd = video_device_alloc();
if (!solo_dev->vfd)
return -ENOMEM;
*solo_dev->vfd = solo_v4l2_template;
solo_dev->vfd->v4l2_dev = &solo_dev->v4l2_dev;
solo_dev->vfd->queue = &solo_dev->vidq;
solo_dev->vfd->lock = &solo_dev->lock;
v4l2_ctrl_handler_init(&solo_dev->disp_hdl, 1);
v4l2_ctrl_new_custom(&solo_dev->disp_hdl, &solo_motion_trace_ctrl, NULL);
if (solo_dev->disp_hdl.error) {
ret = solo_dev->disp_hdl.error;
goto fail;
}
solo_dev->vfd->ctrl_handler = &solo_dev->disp_hdl;
video_set_drvdata(solo_dev->vfd, solo_dev);
solo_dev->vidq.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
solo_dev->vidq.io_modes = VB2_MMAP | VB2_USERPTR | VB2_READ;
solo_dev->vidq.ops = &solo_video_qops;
solo_dev->vidq.mem_ops = &vb2_dma_contig_memops;
solo_dev->vidq.drv_priv = solo_dev;
solo_dev->vidq.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
solo_dev->vidq.gfp_flags = __GFP_DMA32 | __GFP_KSWAPD_RECLAIM;
solo_dev->vidq.buf_struct_size = sizeof(struct solo_vb2_buf);
solo_dev->vidq.lock = &solo_dev->lock;
solo_dev->vidq.dev = &solo_dev->pdev->dev;
ret = vb2_queue_init(&solo_dev->vidq);
if (ret < 0)
goto fail;
/* Cycle all the channels and clear */
for (i = 0; i < solo_dev->nr_chans; i++) {
solo_v4l2_set_ch(solo_dev, i);
while (erase_off(solo_dev))
/* Do nothing */;
}
/* Set the default display channel */
solo_v4l2_set_ch(solo_dev, 0);
while (erase_off(solo_dev))
/* Do nothing */;
ret = video_register_device(solo_dev->vfd, VFL_TYPE_GRABBER, nr);
if (ret < 0)
goto fail;
snprintf(solo_dev->vfd->name, sizeof(solo_dev->vfd->name), "%s (%i)",
SOLO6X10_NAME, solo_dev->vfd->num);
dev_info(&solo_dev->pdev->dev, "Display as /dev/video%d with %d inputs (%d extended)\n",
solo_dev->vfd->num,
solo_dev->nr_chans, solo_dev->nr_ext);
return 0;
fail:
video_device_release(solo_dev->vfd);
v4l2_ctrl_handler_free(&solo_dev->disp_hdl);
solo_dev->vfd = NULL;
return ret;
}
void solo_v4l2_exit(struct solo_dev *solo_dev)
{
if (solo_dev->vfd == NULL)
return;
video_unregister_device(solo_dev->vfd);
v4l2_ctrl_handler_free(&solo_dev->disp_hdl);
solo_dev->vfd = NULL;
}