// SPDX-License-Identifier: GPL-2.0
/*
* video.c - V4L2 component for Mostcore
*
* Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/suspend.h>
#include <linux/videodev2.h>
#include <linux/mutex.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-fh.h>
#include <linux/most.h>
#define V4L2_CMP_MAX_INPUT 1
static struct most_component comp;
struct most_video_dev {
struct most_interface *iface;
int ch_idx;
struct list_head list;
bool mute;
struct list_head pending_mbos;
spinlock_t list_lock;
struct v4l2_device v4l2_dev;
atomic_t access_ref;
struct video_device *vdev;
unsigned int ctrl_input;
struct mutex lock;
wait_queue_head_t wait_data;
};
struct comp_fh {
/* must be the first field of this struct! */
struct v4l2_fh fh;
struct most_video_dev *mdev;
u32 offs;
};
static LIST_HEAD(video_devices);
static DEFINE_SPINLOCK(list_lock);
static inline bool data_ready(struct most_video_dev *mdev)
{
return !list_empty(&mdev->pending_mbos);
}
static inline struct mbo *get_top_mbo(struct most_video_dev *mdev)
{
return list_first_entry(&mdev->pending_mbos, struct mbo, list);
}
static int comp_vdev_open(struct file *filp)
{
int ret;
struct video_device *vdev = video_devdata(filp);
struct most_video_dev *mdev = video_drvdata(filp);
struct comp_fh *fh;
switch (vdev->vfl_type) {
case VFL_TYPE_VIDEO:
break;
default:
return -EINVAL;
}
fh = kzalloc(sizeof(*fh), GFP_KERNEL);
if (!fh)
return -ENOMEM;
if (!atomic_inc_and_test(&mdev->access_ref)) {
v4l2_err(&mdev->v4l2_dev, "too many clients\n");
ret = -EBUSY;
goto err_dec;
}
fh->mdev = mdev;
v4l2_fh_init(&fh->fh, vdev);
filp->private_data = fh;
v4l2_fh_add(&fh->fh);
ret = most_start_channel(mdev->iface, mdev->ch_idx, &comp);
if (ret) {
v4l2_err(&mdev->v4l2_dev, "most_start_channel() failed\n");
goto err_rm;
}
return 0;
err_rm:
v4l2_fh_del(&fh->fh);
v4l2_fh_exit(&fh->fh);
err_dec:
atomic_dec(&mdev->access_ref);
kfree(fh);
return ret;
}
static int comp_vdev_close(struct file *filp)
{
struct comp_fh *fh = filp->private_data;
struct most_video_dev *mdev = fh->mdev;
struct mbo *mbo, *tmp;
/*
* We need to put MBOs back before we call most_stop_channel()
* to deallocate MBOs.
* From the other hand mostcore still calling rx_completion()
* to deliver MBOs until most_stop_channel() is called.
* Use mute to work around this issue.
* This must be implemented in core.
*/
spin_lock_irq(&mdev->list_lock);
mdev->mute = true;
list_for_each_entry_safe(mbo, tmp, &mdev->pending_mbos, list) {
list_del(&mbo->list);
spin_unlock_irq(&mdev->list_lock);
most_put_mbo(mbo);
spin_lock_irq(&mdev->list_lock);
}
spin_unlock_irq(&mdev->list_lock);
most_stop_channel(mdev->iface, mdev->ch_idx, &comp);
mdev->mute = false;
v4l2_fh_del(&fh->fh);
v4l2_fh_exit(&fh->fh);
atomic_dec(&mdev->access_ref);
kfree(fh);
return 0;
}
static ssize_t comp_vdev_read(struct file *filp, char __user *buf,
size_t count, loff_t *pos)
{
struct comp_fh *fh = filp->private_data;
struct most_video_dev *mdev = fh->mdev;
int ret = 0;
if (*pos)
return -ESPIPE;
if (!mdev)
return -ENODEV;
/* wait for the first buffer */
if (!(filp->f_flags & O_NONBLOCK)) {
if (wait_event_interruptible(mdev->wait_data, data_ready(mdev)))
return -ERESTARTSYS;
}
if (!data_ready(mdev))
return -EAGAIN;
while (count > 0 && data_ready(mdev)) {
struct mbo *const mbo = get_top_mbo(mdev);
int const rem = mbo->processed_length - fh->offs;
int const cnt = rem < count ? rem : count;
if (copy_to_user(buf, mbo->virt_address + fh->offs, cnt)) {
v4l2_err(&mdev->v4l2_dev, "read: copy_to_user failed\n");
if (!ret)
ret = -EFAULT;
return ret;
}
fh->offs += cnt;
count -= cnt;
buf += cnt;
ret += cnt;
if (cnt >= rem) {
fh->offs = 0;
spin_lock_irq(&mdev->list_lock);
list_del(&mbo->list);
spin_unlock_irq(&mdev->list_lock);
most_put_mbo(mbo);
}
}
return ret;
}
static __poll_t comp_vdev_poll(struct file *filp, poll_table *wait)
{
struct comp_fh *fh = filp->private_data;
struct most_video_dev *mdev = fh->mdev;
__poll_t mask = 0;
/* only wait if no data is available */
if (!data_ready(mdev))
poll_wait(filp, &mdev->wait_data, wait);
if (data_ready(mdev))
mask |= EPOLLIN | EPOLLRDNORM;
return mask;
}
static void comp_set_format_struct(struct v4l2_format *f)
{
f->fmt.pix.width = 8;
f->fmt.pix.height = 8;
f->fmt.pix.pixelformat = V4L2_PIX_FMT_MPEG;
f->fmt.pix.bytesperline = 0;
f->fmt.pix.sizeimage = 188 * 2;
f->fmt.pix.colorspace = V4L2_COLORSPACE_REC709;
f->fmt.pix.field = V4L2_FIELD_NONE;
f->fmt.pix.priv = 0;
}
static int comp_set_format(struct most_video_dev *mdev, unsigned int cmd,
struct v4l2_format *format)
{
if (format->fmt.pix.pixelformat != V4L2_PIX_FMT_MPEG)
return -EINVAL;
if (cmd == VIDIOC_TRY_FMT)
return 0;
comp_set_format_struct(format);
return 0;
}
static int vidioc_querycap(struct file *file, void *priv,
struct v4l2_capability *cap)
{
struct comp_fh *fh = priv;
struct most_video_dev *mdev = fh->mdev;
strscpy(cap->driver, "v4l2_component", sizeof(cap->driver));
strscpy(cap->card, "MOST", sizeof(cap->card));
snprintf(cap->bus_info, sizeof(cap->bus_info),
"%s", mdev->iface->description);
return 0;
}
static int vidioc_enum_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_fmtdesc *f)
{
if (f->index)
return -EINVAL;
strscpy(f->description, "MPEG", sizeof(f->description));
f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
f->flags = V4L2_FMT_FLAG_COMPRESSED;
f->pixelformat = V4L2_PIX_FMT_MPEG;
return 0;
}
static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
comp_set_format_struct(f);
return 0;
}
static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct comp_fh *fh = priv;
struct most_video_dev *mdev = fh->mdev;
return comp_set_format(mdev, VIDIOC_TRY_FMT, f);
}
static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct comp_fh *fh = priv;
struct most_video_dev *mdev = fh->mdev;
return comp_set_format(mdev, VIDIOC_S_FMT, f);
}
static int vidioc_g_std(struct file *file, void *priv, v4l2_std_id *norm)
{
*norm = V4L2_STD_UNKNOWN;
return 0;
}
static int vidioc_enum_input(struct file *file, void *priv,
struct v4l2_input *input)
{
struct comp_fh *fh = priv;
struct most_video_dev *mdev = fh->mdev;
if (input->index >= V4L2_CMP_MAX_INPUT)
return -EINVAL;
strscpy(input->name, "MOST Video", sizeof(input->name));
input->type |= V4L2_INPUT_TYPE_CAMERA;
input->audioset = 0;
input->std = mdev->vdev->tvnorms;
return 0;
}
static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
{
struct comp_fh *fh = priv;
struct most_video_dev *mdev = fh->mdev;
*i = mdev->ctrl_input;
return 0;
}
static int vidioc_s_input(struct file *file, void *priv, unsigned int index)
{
struct comp_fh *fh = priv;
struct most_video_dev *mdev = fh->mdev;
if (index >= V4L2_CMP_MAX_INPUT)
return -EINVAL;
mdev->ctrl_input = index;
return 0;
}
static const struct v4l2_file_operations comp_fops = {
.owner = THIS_MODULE,
.open = comp_vdev_open,
.release = comp_vdev_close,
.read = comp_vdev_read,
.poll = comp_vdev_poll,
.unlocked_ioctl = video_ioctl2,
};
static const struct v4l2_ioctl_ops video_ioctl_ops = {
.vidioc_querycap = vidioc_querycap,
.vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap,
.vidioc_g_fmt_vid_cap = vidioc_g_fmt_vid_cap,
.vidioc_try_fmt_vid_cap = vidioc_try_fmt_vid_cap,
.vidioc_s_fmt_vid_cap = vidioc_s_fmt_vid_cap,
.vidioc_g_std = vidioc_g_std,
.vidioc_enum_input = vidioc_enum_input,
.vidioc_g_input = vidioc_g_input,
.vidioc_s_input = vidioc_s_input,
};
static const struct video_device comp_videodev_template = {
.fops = &comp_fops,
.release = video_device_release,
.ioctl_ops = &video_ioctl_ops,
.tvnorms = V4L2_STD_UNKNOWN,
.device_caps = V4L2_CAP_READWRITE | V4L2_CAP_VIDEO_CAPTURE,
};
/**************************************************************************/
static struct most_video_dev *get_comp_dev(struct most_interface *iface, int channel_idx)
{
struct most_video_dev *mdev;
unsigned long flags;
spin_lock_irqsave(&list_lock, flags);
list_for_each_entry(mdev, &video_devices, list) {
if (mdev->iface == iface && mdev->ch_idx == channel_idx) {
spin_unlock_irqrestore(&list_lock, flags);
return mdev;
}
}
spin_unlock_irqrestore(&list_lock, flags);
return NULL;
}
static int comp_rx_data(struct mbo *mbo)
{
unsigned long flags;
struct most_video_dev *mdev =
get_comp_dev(mbo->ifp, mbo->hdm_channel_id);
if (!mdev)
return -EIO;
spin_lock_irqsave(&mdev->list_lock, flags);
if (unlikely(mdev->mute)) {
spin_unlock_irqrestore(&mdev->list_lock, flags);
return -EIO;
}
list_add_tail(&mbo->list, &mdev->pending_mbos);
spin_unlock_irqrestore(&mdev->list_lock, flags);
wake_up_interruptible(&mdev->wait_data);
return 0;
}
static int comp_register_videodev(struct most_video_dev *mdev)
{
int ret;
init_waitqueue_head(&mdev->wait_data);
/* allocate and fill v4l2 video struct */
mdev->vdev = video_device_alloc();
if (!mdev->vdev)
return -ENOMEM;
/* Fill the video capture device struct */
*mdev->vdev = comp_videodev_template;
mdev->vdev->v4l2_dev = &mdev->v4l2_dev;
mdev->vdev->lock = &mdev->lock;
snprintf(mdev->vdev->name, sizeof(mdev->vdev->name), "MOST: %s",
mdev->v4l2_dev.name);
/* Register the v4l2 device */
video_set_drvdata(mdev->vdev, mdev);
ret = video_register_device(mdev->vdev, VFL_TYPE_VIDEO, -1);
if (ret) {
v4l2_err(&mdev->v4l2_dev, "video_register_device failed (%d)\n",
ret);
video_device_release(mdev->vdev);
}
return ret;
}
static void comp_unregister_videodev(struct most_video_dev *mdev)
{
video_unregister_device(mdev->vdev);
}
static void comp_v4l2_dev_release(struct v4l2_device *v4l2_dev)
{
struct most_video_dev *mdev =
container_of(v4l2_dev, struct most_video_dev, v4l2_dev);
v4l2_device_unregister(v4l2_dev);
kfree(mdev);
}
static int comp_probe_channel(struct most_interface *iface, int channel_idx,
struct most_channel_config *ccfg, char *name,
char *args)
{
int ret;
struct most_video_dev *mdev = get_comp_dev(iface, channel_idx);
if (mdev) {
pr_err("Channel already linked\n");
return -EEXIST;
}
if (ccfg->direction != MOST_CH_RX) {
pr_err("Wrong direction, expected rx\n");
return -EINVAL;
}
if (ccfg->data_type != MOST_CH_SYNC &&
ccfg->data_type != MOST_CH_ISOC) {
pr_err("Wrong channel type, expected sync or isoc\n");
return -EINVAL;
}
mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
if (!mdev)
return -ENOMEM;
mutex_init(&mdev->lock);
atomic_set(&mdev->access_ref, -1);
spin_lock_init(&mdev->list_lock);
INIT_LIST_HEAD(&mdev->pending_mbos);
mdev->iface = iface;
mdev->ch_idx = channel_idx;
mdev->v4l2_dev.release = comp_v4l2_dev_release;
/* Create the v4l2_device */
strscpy(mdev->v4l2_dev.name, name, sizeof(mdev->v4l2_dev.name));
ret = v4l2_device_register(NULL, &mdev->v4l2_dev);
if (ret) {
pr_err("v4l2_device_register() failed\n");
kfree(mdev);
return ret;
}
ret = comp_register_videodev(mdev);
if (ret)
goto err_unreg;
spin_lock_irq(&list_lock);
list_add(&mdev->list, &video_devices);
spin_unlock_irq(&list_lock);
return 0;
err_unreg:
v4l2_device_disconnect(&mdev->v4l2_dev);
v4l2_device_put(&mdev->v4l2_dev);
return ret;
}
static int comp_disconnect_channel(struct most_interface *iface,
int channel_idx)
{
struct most_video_dev *mdev = get_comp_dev(iface, channel_idx);
if (!mdev) {
pr_err("no such channel is linked\n");
return -ENOENT;
}
spin_lock_irq(&list_lock);
list_del(&mdev->list);
spin_unlock_irq(&list_lock);
comp_unregister_videodev(mdev);
v4l2_device_disconnect(&mdev->v4l2_dev);
v4l2_device_put(&mdev->v4l2_dev);
return 0;
}
static struct most_component comp = {
.mod = THIS_MODULE,
.name = "video",
.probe_channel = comp_probe_channel,
.disconnect_channel = comp_disconnect_channel,
.rx_completion = comp_rx_data,
};
static int __init comp_init(void)
{
int err;
err = most_register_component(&comp);
if (err)
return err;
err = most_register_configfs_subsys(&comp);
if (err) {
most_deregister_component(&comp);
return err;
}
return 0;
}
static void __exit comp_exit(void)
{
struct most_video_dev *mdev, *tmp;
/*
* As the mostcore currently doesn't call disconnect_channel()
* for linked channels while we call most_deregister_component()
* we simulate this call here.
* This must be fixed in core.
*/
spin_lock_irq(&list_lock);
list_for_each_entry_safe(mdev, tmp, &video_devices, list) {
list_del(&mdev->list);
spin_unlock_irq(&list_lock);
comp_unregister_videodev(mdev);
v4l2_device_disconnect(&mdev->v4l2_dev);
v4l2_device_put(&mdev->v4l2_dev);
spin_lock_irq(&list_lock);
}
spin_unlock_irq(&list_lock);
most_deregister_configfs_subsys(&comp);
most_deregister_component(&comp);
BUG_ON(!list_empty(&video_devices));
}
module_init(comp_init);
module_exit(comp_exit);
MODULE_DESCRIPTION("V4L2 Component Module for Mostcore");
MODULE_AUTHOR("Andrey Shvetsov <[email protected]>");
MODULE_LICENSE("GPL");
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