Staging: most: add MOST driver's aim-v4l2 module (3d31c0cb) · Commits · jan.koester / Linux

drivers/staging/most/Kconfig

+2 −0

Original line number	Diff line number	Diff line
		@@ -19,4 +19,6 @@ source "drivers/staging/most/aim-network/Kconfig"

		source "drivers/staging/most/aim-sound/Kconfig"

		source "drivers/staging/most/aim-v4l2/Kconfig"

		endif

drivers/staging/most/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -2,3 +2,4 @@ obj-$(CONFIG_MOSTCORE) += mostcore/
		obj-$(CONFIG_AIM_CDEV) += aim-cdev/
		obj-$(CONFIG_AIM_NETWORK) += aim-network/
		obj-$(CONFIG_AIM_SOUND) += aim-sound/
		obj-$(CONFIG_AIM_V4L2) += aim-v4l2/

drivers/staging/most/aim-v4l2/Kconfig

0 → 100644

+12 −0

Original line number	Diff line number	Diff line
		#
		# MOST V4L2 configuration
		#

		config AIM_V4L2
		tristate "V4L2 AIM"
		depends on VIDEO_V4L2
		---help---
		Say Y here if you want to commumicate via Video 4 Linux.

		To compile this driver as a module, choose M here: the
		module will be called aim_v4l2.
		No newline at end of file

drivers/staging/most/aim-v4l2/Makefile

0 → 100644

+6 −0

Original line number	Diff line number	Diff line
		obj-$(CONFIG_AIM_V4L2) += aim_v4l2.o

		aim_v4l2-objs := video.o

		ccflags-y += -Idrivers/staging/most/mostcore/
		ccflags-y += -Idrivers/media/video

drivers/staging/most/aim-v4l2/video.c

0 → 100644

+634 −0

Original line number	Diff line number	Diff line
		/*
		* V4L2 AIM - V4L2 Application Interface Module for MostCore
		*
		* Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
		*
		* 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.
		*
		* This file is licensed under GPLv2.
		*/

		#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 "mostcore.h"


		#define V4L2_AIM_MAX_INPUT 1


		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 aim_fh {
		/* must be the first field of this struct! */
		struct v4l2_fh fh;
		struct most_video_dev *mdev;
		u32 offs;
		};


		static struct list_head video_devices = LIST_HEAD_INIT(video_devices);
		static struct spinlock list_lock;
		static struct most_aim aim_info;


		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 aim_vdev_open(struct file *filp)
		{
		int ret;
		struct video_device *vdev = video_devdata(filp);
		struct most_video_dev *mdev = video_drvdata(filp);
		struct aim_fh *fh;

		pr_info("aim_vdev_open()\n");

		switch (vdev->vfl_type) {
		case VFL_TYPE_GRABBER:
		break;
		default:
		return -EINVAL;
		}

		fh = kzalloc(sizeof(struct aim_fh), GFP_KERNEL);
		if (!fh)
		return -ENOMEM;

		if (!atomic_inc_and_test(&mdev->access_ref)) {
		pr_err("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);
		if (ret) {
		pr_err("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 aim_vdev_close(struct file *filp)
		{
		struct aim_fh *fh = filp->private_data;
		struct most_video_dev *mdev = fh->mdev;
		struct mbo mbo, tmp;

		pr_info("aim_vdev_close()\n");

		/*
		* 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(&mdev->list_lock);
		mdev->mute = true;
		list_for_each_entry_safe(mbo, tmp, &mdev->pending_mbos, list) {
		list_del(&mbo->list);
		spin_unlock(&mdev->list_lock);
		most_put_mbo(mbo);
		spin_lock(&mdev->list_lock);
		}
		spin_unlock(&mdev->list_lock);
		most_stop_channel(mdev->iface, mdev->ch_idx);
		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 aim_vdev_read(struct file filp, char __user buf,
		size_t count, loff_t *pos)
		{
		struct aim_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)) {
		pr_err("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(&mdev->list_lock);
		list_del(&mbo->list);
		spin_unlock(&mdev->list_lock);
		most_put_mbo(mbo);
		}
		}
		return ret;
		}

		static unsigned int aim_vdev_poll(struct file filp, poll_table wait)
		{
		struct aim_fh *fh = filp->private_data;
		struct most_video_dev *mdev = fh->mdev;
		unsigned int 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 \|= POLLIN \| POLLRDNORM;

		return mask;
		}

		static void aim_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 aim_set_format(struct most_video_dev *mdev, unsigned int cmd,
		struct v4l2_format *format)
		{
		#if 0
		u32 const pixfmt = format->fmt.pix.pixelformat;
		const char *fmt;

		if (pixfmt != V4L2_PIX_FMT_MPEG) {
		if (cmd == VIDIOC_TRY_FMT)
		fmt = KERN_ERR "try %c%c%c%c failed\n";
		else
		fmt = KERN_ERR "set %c%c%c%c failed\n";
		} else {
		if (cmd == VIDIOC_TRY_FMT)
		fmt = KERN_ERR "try %c%c%c%c\n";
		else
		fmt = KERN_ERR "set %c%c%c%c\n";
		}
		printk(fmt,
		(pixfmt) & 255,
		(pixfmt >> 8) & 255,
		(pixfmt >> 16) & 255,
		(pixfmt >> 24) & 255);
		#endif

		if (format->fmt.pix.pixelformat != V4L2_PIX_FMT_MPEG)
		return -EINVAL;

		if (cmd == VIDIOC_TRY_FMT)
		return 0;

		aim_set_format_struct(format);

		return 0;
		}


		static int vidioc_querycap(struct file file, void priv,
		struct v4l2_capability *cap)
		{
		struct aim_fh *fh = priv;
		struct most_video_dev *mdev = fh->mdev;

		pr_info("vidioc_querycap()\n");

		strlcpy(cap->driver, "v4l2_most_aim", sizeof(cap->driver));
		strlcpy(cap->card, "my_card", sizeof(cap->card));
		snprintf(cap->bus_info, sizeof(cap->bus_info),
		"%s", mdev->iface->description);

		cap->capabilities =
		V4L2_CAP_READWRITE \|
		V4L2_CAP_TUNER \|
		V4L2_CAP_VIDEO_CAPTURE;
		return 0;
		}

		static int vidioc_enum_fmt_vid_cap(struct file file, void priv,
		struct v4l2_fmtdesc *f)
		{
		pr_info("vidioc_enum_fmt_vid_cap() %d\n", f->index);

		if (f->index)
		return -EINVAL;

		strcpy(f->description, "MPEG");
		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)
		{
		pr_info("vidioc_g_fmt_vid_cap()\n");

		aim_set_format_struct(f);
		return 0;
		}

		static int vidioc_try_fmt_vid_cap(struct file file, void priv,
		struct v4l2_format *f)
		{
		struct aim_fh *fh = priv;
		struct most_video_dev *mdev = fh->mdev;

		return aim_set_format(mdev, VIDIOC_TRY_FMT, f);
		}

		static int vidioc_s_fmt_vid_cap(struct file file, void priv,
		struct v4l2_format *f)
		{
		struct aim_fh *fh = priv;
		struct most_video_dev *mdev = fh->mdev;

		return aim_set_format(mdev, VIDIOC_S_FMT, f);
		}

		static int vidioc_g_std(struct file file, void priv, v4l2_std_id *norm)
		{
		pr_info("vidioc_g_std()\n");

		*norm = V4L2_STD_UNKNOWN;
		return 0;
		}

		static int vidioc_enum_input(struct file file, void priv,
		struct v4l2_input *input)
		{
		struct aim_fh *fh = priv;
		struct most_video_dev *mdev = fh->mdev;

		if (input->index >= V4L2_AIM_MAX_INPUT)
		return -EINVAL;

		strcpy(input->name, "MOST Video");
		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 aim_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 aim_fh *fh = priv;
		struct most_video_dev *mdev = fh->mdev;

		pr_info("vidioc_s_input(%d)\n", index);

		if (index >= V4L2_AIM_MAX_INPUT)
		return -EINVAL;
		mdev->ctrl_input = index;
		return 0;
		}

		static struct v4l2_file_operations aim_fops = {
		.owner = THIS_MODULE,
		.open = aim_vdev_open,
		.release = aim_vdev_close,
		.read = aim_vdev_read,
		.poll = aim_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 aim_videodev_template = {
		.fops = &aim_fops,
		.release = video_device_release,
		.ioctl_ops = &video_ioctl_ops,
		.tvnorms = V4L2_STD_UNKNOWN,
		};

		/**************************************************************************/

		static struct most_video_dev *get_aim_dev(
		struct most_interface *iface, int channel_idx)
		{
		struct most_video_dev mdev, tmp;

		spin_lock(&list_lock);
		list_for_each_entry_safe(mdev, tmp, &video_devices, list) {
		if (mdev->iface == iface && mdev->ch_idx == channel_idx) {
		spin_unlock(&list_lock);
		return mdev;
		}
		}
		spin_unlock(&list_lock);
		return 0;
		}

		static int aim_rx_data(struct mbo *mbo)
		{
		struct most_video_dev *mdev =
		get_aim_dev(mbo->ifp, mbo->hdm_channel_id);

		if (!mdev)
		return -EIO;

		spin_lock(&mdev->list_lock);
		if (unlikely(mdev->mute)) {
		spin_unlock(&mdev->list_lock);
		return -EIO;
		}

		list_add_tail(&mbo->list, &mdev->pending_mbos);
		spin_unlock(&mdev->list_lock);
		wake_up_interruptible(&mdev->wait_data);
		return 0;
		}

		static int aim_register_videodev(struct most_video_dev *mdev)
		{
		int retval = -ENOMEM;
		int ret;

		pr_info("aim_register_videodev()\n");

		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 = aim_videodev_template;
		mdev->vdev->v4l2_dev = &mdev->v4l2_dev;
		mdev->vdev->lock = &mdev->lock;
		strcpy(mdev->vdev->name, "most v4l2 aim video");

		/* Register the v4l2 device */
		video_set_drvdata(mdev->vdev, mdev);
		retval = video_register_device(mdev->vdev, VFL_TYPE_GRABBER, -1);
		if (retval != 0) {
		pr_err("video_register_device failed (%d)\n", retval);
		ret = -ENODEV;
		goto err_vbi_dev;
		}

		return 0;

		err_vbi_dev:
		video_device_release(mdev->vdev);
		return ret;
		}

		static void aim_unregister_videodev(struct most_video_dev *mdev)
		{
		pr_info("aim_unregister_videodev()\n");

		video_unregister_device(mdev->vdev);
		}


		static void aim_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 aim_probe_channel(struct most_interface *iface, int channel_idx,
		struct most_channel_config *ccfg,
		struct kobject parent, char name)
		{
		int ret;
		struct most_video_dev *mdev = get_aim_dev(iface, channel_idx);

		pr_info("aim_probe_channel()\n");

		if (mdev) {
		pr_err("channel already linked\n");
		return -EEXIST;
		}

		if (ccfg->direction != MOST_CH_RX) {
		pr_err("wrong direction, expect rx\n");
		return -EINVAL;
		}

		if (ccfg->data_type != MOST_CH_SYNC &&
		ccfg->data_type != MOST_CH_ISOC_AVP) {
		pr_err("wrong channel type, expect sync or isoc_avp\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 = aim_v4l2_dev_release;

		/* Create the v4l2_device */
		strlcpy(mdev->v4l2_dev.name, "most_video_device",
		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 = aim_register_videodev(mdev);
		if (ret)
		goto err_unreg;

		spin_lock(&list_lock);
		list_add(&mdev->list, &video_devices);
		spin_unlock(&list_lock);
		return 0;

		err_unreg:
		v4l2_device_disconnect(&mdev->v4l2_dev);
		v4l2_device_put(&mdev->v4l2_dev);
		return ret;
		}

		static int aim_disconnect_channel(struct most_interface *iface,
		int channel_idx)
		{
		struct most_video_dev *mdev = get_aim_dev(iface, channel_idx);

		pr_info("aim_disconnect_channel()\n");

		if (!mdev) {
		pr_err("no such channel is linked\n");
		return -ENOENT;
		}

		spin_lock(&list_lock);
		list_del(&mdev->list);
		spin_unlock(&list_lock);

		aim_unregister_videodev(mdev);
		v4l2_device_disconnect(&mdev->v4l2_dev);
		v4l2_device_put(&mdev->v4l2_dev);
		return 0;
		}

		static int __init aim_init(void)
		{
		spin_lock_init(&list_lock);

		aim_info.name = "v4l";
		aim_info.probe_channel = aim_probe_channel;
		aim_info.disconnect_channel = aim_disconnect_channel;
		aim_info.rx_completion = aim_rx_data;
		return most_register_aim(&aim_info);
		}

		static void __exit aim_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_aim()
		* we simulate this call here.
		* This must be fixed in core.
		*/
		spin_lock(&list_lock);
		list_for_each_entry_safe(mdev, tmp, &video_devices, list) {
		list_del(&mdev->list);
		spin_unlock(&list_lock);

		aim_unregister_videodev(mdev);
		v4l2_device_disconnect(&mdev->v4l2_dev);
		v4l2_device_put(&mdev->v4l2_dev);
		}
		spin_unlock(&list_lock);

		most_deregister_aim(&aim_info);
		BUG_ON(!list_empty(&video_devices));
		}

		module_init(aim_init);
		module_exit(aim_exit);

		MODULE_DESCRIPTION("V4L2 Application Interface Module for MostCore");
		MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>");
		MODULE_LICENSE("GPL");