drivers/media/platform/vivid/vivid-kthread-out.c - kernel/bruno - Git at Google

 /*
  * vivid-kthread-out.h - video/vbi output thread support functions.
  *
  * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
  *
  * This program is free software; you may redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; version 2 of the License.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */

 #include <linux/module.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/font.h>
 #include <linux/mutex.h>
 #include <linux/videodev2.h>
 #include <linux/kthread.h>
 #include <linux/freezer.h>
 #include <linux/random.h>
 #include <linux/v4l2-dv-timings.h>
 #include <asm/div64.h>
 #include <media/videobuf2-vmalloc.h>
 #include <media/v4l2-dv-timings.h>
 #include <media/v4l2-ioctl.h>
 #include <media/v4l2-fh.h>
 #include <media/v4l2-event.h>

 #include "vivid-core.h"
 #include "vivid-vid-common.h"
 #include "vivid-vid-cap.h"
 #include "vivid-vid-out.h"
 #include "vivid-radio-common.h"
 #include "vivid-radio-rx.h"
 #include "vivid-radio-tx.h"
 #include "vivid-sdr-cap.h"
 #include "vivid-vbi-cap.h"
 #include "vivid-vbi-out.h"
 #include "vivid-osd.h"
 #include "vivid-ctrls.h"
 #include "vivid-kthread-out.h"

 static void vivid_thread_vid_out_tick(struct vivid_dev *dev)
 {
 	struct vivid_buffer *vid_out_buf = NULL;
 	struct vivid_buffer *vbi_out_buf = NULL;

 	dprintk(dev, 1, "Video Output Thread Tick\n");

 	/* Drop a certain percentage of buffers. */
 	if (dev->perc_dropped_buffers &&
 	    prandom_u32_max(100) < dev->perc_dropped_buffers)
 		return;

 	spin_lock(&dev->slock);
 	/*
 	 * Only dequeue buffer if there is at least one more pending.
 	 * This makes video loopback possible.
 	 */
 	if (!list_empty(&dev->vid_out_active) &&
 	    !list_is_singular(&dev->vid_out_active)) {
 		vid_out_buf = list_entry(dev->vid_out_active.next,
 					 struct vivid_buffer, list);
 		list_del(&vid_out_buf->list);
 	}
 	if (!list_empty(&dev->vbi_out_active) &&
 	    (dev->field_out != V4L2_FIELD_ALTERNATE ||
 	     (dev->vbi_out_seq_count & 1))) {
 		vbi_out_buf = list_entry(dev->vbi_out_active.next,
 					 struct vivid_buffer, list);
 		list_del(&vbi_out_buf->list);
 	}
 	spin_unlock(&dev->slock);

 	if (!vid_out_buf && !vbi_out_buf)
 		return;

 	if (vid_out_buf) {
 		vid_out_buf->vb.sequence = dev->vid_out_seq_count;
 		if (dev->field_out == V4L2_FIELD_ALTERNATE) {
 			/*
 			 * The sequence counter counts frames, not fields.
 			 * So divide by two.
 			 */
 			vid_out_buf->vb.sequence /= 2;
 		}
 		v4l2_get_timestamp(&vid_out_buf->vb.timestamp);
 		vid_out_buf->vb.timestamp.tv_sec += dev->time_wrap_offset;
 		vb2_buffer_done(&vid_out_buf->vb.vb2_buf, dev->dqbuf_error ?
 				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
 		dprintk(dev, 2, "vid_out buffer %d done\n",
 			vid_out_buf->vb.vb2_buf.index);
 	}

 	if (vbi_out_buf) {
 		if (dev->stream_sliced_vbi_out)
 			vivid_sliced_vbi_out_process(dev, vbi_out_buf);

 		vbi_out_buf->vb.sequence = dev->vbi_out_seq_count;
 		v4l2_get_timestamp(&vbi_out_buf->vb.timestamp);
 		vbi_out_buf->vb.timestamp.tv_sec += dev->time_wrap_offset;
 		vb2_buffer_done(&vbi_out_buf->vb.vb2_buf, dev->dqbuf_error ?
 				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
 		dprintk(dev, 2, "vbi_out buffer %d done\n",
 			vbi_out_buf->vb.vb2_buf.index);
 	}
 	dev->dqbuf_error = false;
 }

 static int vivid_thread_vid_out(void *data)
 {
 	struct vivid_dev *dev = data;
 	u64 numerators_since_start;
 	u64 buffers_since_start;
 	u64 next_jiffies_since_start;
 	unsigned long jiffies_since_start;
 	unsigned long cur_jiffies;
 	unsigned wait_jiffies;
 	unsigned numerator;
 	unsigned denominator;

 	dprintk(dev, 1, "Video Output Thread Start\n");

 	set_freezable();

 	/* Resets frame counters */
 	dev->out_seq_offset = 0;
 	if (dev->seq_wrap)
 		dev->out_seq_count = 0xffffff80U;
 	dev->jiffies_vid_out = jiffies;
 	dev->vid_out_seq_start = dev->vbi_out_seq_start = 0;
 	dev->out_seq_resync = false;

 	for (;;) {
 		try_to_freeze();
 		if (kthread_should_stop())
 			break;

 		mutex_lock(&dev->mutex);
 		cur_jiffies = jiffies;
 		if (dev->out_seq_resync) {
 			dev->jiffies_vid_out = cur_jiffies;
 			dev->out_seq_offset = dev->out_seq_count + 1;
 			dev->out_seq_count = 0;
 			dev->out_seq_resync = false;
 		}
 		numerator = dev->timeperframe_vid_out.numerator;
 		denominator = dev->timeperframe_vid_out.denominator;

 		if (dev->field_out == V4L2_FIELD_ALTERNATE)
 			denominator *= 2;

 		/* Calculate the number of jiffies since we started streaming */
 		jiffies_since_start = cur_jiffies - dev->jiffies_vid_out;
 		/* Get the number of buffers streamed since the start */
 		buffers_since_start = (u64)jiffies_since_start * denominator +
 				      (HZ * numerator) / 2;
 		do_div(buffers_since_start, HZ * numerator);

 		/*
 		 * After more than 0xf0000000 (rounded down to a multiple of
 		 * 'jiffies-per-day' to ease jiffies_to_msecs calculation)
 		 * jiffies have passed since we started streaming reset the
 		 * counters and keep track of the sequence offset.
 		 */
 		if (jiffies_since_start > JIFFIES_RESYNC) {
 			dev->jiffies_vid_out = cur_jiffies;
 			dev->out_seq_offset = buffers_since_start;
 			buffers_since_start = 0;
 		}
 		dev->out_seq_count = buffers_since_start + dev->out_seq_offset;
 		dev->vid_out_seq_count = dev->out_seq_count - dev->vid_out_seq_start;
 		dev->vbi_out_seq_count = dev->out_seq_count - dev->vbi_out_seq_start;

 		vivid_thread_vid_out_tick(dev);
 		mutex_unlock(&dev->mutex);

 		/*
 		 * Calculate the number of 'numerators' streamed since we started,
 		 * not including the current buffer.
 		 */
 		numerators_since_start = buffers_since_start * numerator;

 		/* And the number of jiffies since we started */
 		jiffies_since_start = jiffies - dev->jiffies_vid_out;

 		/* Increase by the 'numerator' of one buffer */
 		numerators_since_start += numerator;
 		/*
 		 * Calculate when that next buffer is supposed to start
 		 * in jiffies since we started streaming.
 		 */
 		next_jiffies_since_start = numerators_since_start * HZ +
 					   denominator / 2;
 		do_div(next_jiffies_since_start, denominator);
 		/* If it is in the past, then just schedule asap */
 		if (next_jiffies_since_start < jiffies_since_start)
 			next_jiffies_since_start = jiffies_since_start;

 		wait_jiffies = next_jiffies_since_start - jiffies_since_start;
 		schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
 	}
 	dprintk(dev, 1, "Video Output Thread End\n");
 	return 0;
 }

 static void vivid_grab_controls(struct vivid_dev *dev, bool grab)
 {
 	v4l2_ctrl_grab(dev->ctrl_has_crop_out, grab);
 	v4l2_ctrl_grab(dev->ctrl_has_compose_out, grab);
 	v4l2_ctrl_grab(dev->ctrl_has_scaler_out, grab);
 	v4l2_ctrl_grab(dev->ctrl_tx_mode, grab);
 	v4l2_ctrl_grab(dev->ctrl_tx_rgb_range, grab);
 }

 int vivid_start_generating_vid_out(struct vivid_dev *dev, bool *pstreaming)
 {
 	dprintk(dev, 1, "%s\n", __func__);

 	if (dev->kthread_vid_out) {
 		u32 seq_count = dev->out_seq_count + dev->seq_wrap * 128;

 		if (pstreaming == &dev->vid_out_streaming)
 			dev->vid_out_seq_start = seq_count;
 		else
 			dev->vbi_out_seq_start = seq_count;
 		*pstreaming = true;
 		return 0;
 	}

 	/* Resets frame counters */
 	dev->jiffies_vid_out = jiffies;
 	dev->vid_out_seq_start = dev->seq_wrap * 128;
 	dev->vbi_out_seq_start = dev->seq_wrap * 128;

 	dev->kthread_vid_out = kthread_run(vivid_thread_vid_out, dev,
 			"%s-vid-out", dev->v4l2_dev.name);

 	if (IS_ERR(dev->kthread_vid_out)) {
 		v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
 		return PTR_ERR(dev->kthread_vid_out);
 	}
 	*pstreaming = true;
 	vivid_grab_controls(dev, true);

 	dprintk(dev, 1, "returning from %s\n", __func__);
 	return 0;
 }

 void vivid_stop_generating_vid_out(struct vivid_dev *dev, bool *pstreaming)
 {
 	dprintk(dev, 1, "%s\n", __func__);

 	if (dev->kthread_vid_out == NULL)
 		return;

 	*pstreaming = false;
 	if (pstreaming == &dev->vid_out_streaming) {
 		/* Release all active buffers */
 		while (!list_empty(&dev->vid_out_active)) {
 			struct vivid_buffer *buf;

 			buf = list_entry(dev->vid_out_active.next,
 					 struct vivid_buffer, list);
 			list_del(&buf->list);
 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
 			dprintk(dev, 2, "vid_out buffer %d done\n",
 				buf->vb.vb2_buf.index);
 		}
 	}

 	if (pstreaming == &dev->vbi_out_streaming) {
 		while (!list_empty(&dev->vbi_out_active)) {
 			struct vivid_buffer *buf;

 			buf = list_entry(dev->vbi_out_active.next,
 					 struct vivid_buffer, list);
 			list_del(&buf->list);
 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
 			dprintk(dev, 2, "vbi_out buffer %d done\n",
 				buf->vb.vb2_buf.index);
 		}
 	}

 	if (dev->vid_out_streaming || dev->vbi_out_streaming)
 		return;

 	/* shutdown control thread */
 	vivid_grab_controls(dev, false);
 	mutex_unlock(&dev->mutex);
 	kthread_stop(dev->kthread_vid_out);
 	dev->kthread_vid_out = NULL;
 	mutex_lock(&dev->mutex);
 }
	/*
	* vivid-kthread-out.h - video/vbi output thread support functions.
	*
	* Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
	*
	* This program is free software; you may redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; version 2 of the License.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	#include <linux/module.h>
	#include <linux/errno.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/sched.h>
	#include <linux/slab.h>
	#include <linux/font.h>
	#include <linux/mutex.h>
	#include <linux/videodev2.h>
	#include <linux/kthread.h>
	#include <linux/freezer.h>
	#include <linux/random.h>
	#include <linux/v4l2-dv-timings.h>
	#include <asm/div64.h>
	#include <media/videobuf2-vmalloc.h>
	#include <media/v4l2-dv-timings.h>
	#include <media/v4l2-ioctl.h>
	#include <media/v4l2-fh.h>
	#include <media/v4l2-event.h>

	#include "vivid-core.h"
	#include "vivid-vid-common.h"
	#include "vivid-vid-cap.h"
	#include "vivid-vid-out.h"
	#include "vivid-radio-common.h"
	#include "vivid-radio-rx.h"
	#include "vivid-radio-tx.h"
	#include "vivid-sdr-cap.h"
	#include "vivid-vbi-cap.h"
	#include "vivid-vbi-out.h"
	#include "vivid-osd.h"
	#include "vivid-ctrls.h"
	#include "vivid-kthread-out.h"

	static void vivid_thread_vid_out_tick(struct vivid_dev *dev)
	{
	struct vivid_buffer *vid_out_buf = NULL;
	struct vivid_buffer *vbi_out_buf = NULL;

	dprintk(dev, 1, "Video Output Thread Tick\n");

	/* Drop a certain percentage of buffers. */
	if (dev->perc_dropped_buffers &&
	prandom_u32_max(100) < dev->perc_dropped_buffers)
	return;

	spin_lock(&dev->slock);
	/*
	* Only dequeue buffer if there is at least one more pending.
	* This makes video loopback possible.
	*/
	if (!list_empty(&dev->vid_out_active) &&
	!list_is_singular(&dev->vid_out_active)) {
	vid_out_buf = list_entry(dev->vid_out_active.next,
	struct vivid_buffer, list);
	list_del(&vid_out_buf->list);
	}
	if (!list_empty(&dev->vbi_out_active) &&
	(dev->field_out != V4L2_FIELD_ALTERNATE \|\|
	(dev->vbi_out_seq_count & 1))) {
	vbi_out_buf = list_entry(dev->vbi_out_active.next,
	struct vivid_buffer, list);
	list_del(&vbi_out_buf->list);
	}
	spin_unlock(&dev->slock);

	if (!vid_out_buf && !vbi_out_buf)
	return;

	if (vid_out_buf) {
	vid_out_buf->vb.sequence = dev->vid_out_seq_count;
	if (dev->field_out == V4L2_FIELD_ALTERNATE) {
	/*
	* The sequence counter counts frames, not fields.
	* So divide by two.
	*/
	vid_out_buf->vb.sequence /= 2;
	}
	v4l2_get_timestamp(&vid_out_buf->vb.timestamp);
	vid_out_buf->vb.timestamp.tv_sec += dev->time_wrap_offset;
	vb2_buffer_done(&vid_out_buf->vb.vb2_buf, dev->dqbuf_error ?
	VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
	dprintk(dev, 2, "vid_out buffer %d done\n",
	vid_out_buf->vb.vb2_buf.index);
	}

	if (vbi_out_buf) {
	if (dev->stream_sliced_vbi_out)
	vivid_sliced_vbi_out_process(dev, vbi_out_buf);

	vbi_out_buf->vb.sequence = dev->vbi_out_seq_count;
	v4l2_get_timestamp(&vbi_out_buf->vb.timestamp);
	vbi_out_buf->vb.timestamp.tv_sec += dev->time_wrap_offset;
	vb2_buffer_done(&vbi_out_buf->vb.vb2_buf, dev->dqbuf_error ?
	VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
	dprintk(dev, 2, "vbi_out buffer %d done\n",
	vbi_out_buf->vb.vb2_buf.index);
	}
	dev->dqbuf_error = false;
	}

	static int vivid_thread_vid_out(void *data)
	{
	struct vivid_dev *dev = data;
	u64 numerators_since_start;
	u64 buffers_since_start;
	u64 next_jiffies_since_start;
	unsigned long jiffies_since_start;
	unsigned long cur_jiffies;
	unsigned wait_jiffies;
	unsigned numerator;
	unsigned denominator;

	dprintk(dev, 1, "Video Output Thread Start\n");

	set_freezable();

	/* Resets frame counters */
	dev->out_seq_offset = 0;
	if (dev->seq_wrap)
	dev->out_seq_count = 0xffffff80U;
	dev->jiffies_vid_out = jiffies;
	dev->vid_out_seq_start = dev->vbi_out_seq_start = 0;
	dev->out_seq_resync = false;

	for (;;) {
	try_to_freeze();
	if (kthread_should_stop())
	break;

	mutex_lock(&dev->mutex);
	cur_jiffies = jiffies;
	if (dev->out_seq_resync) {
	dev->jiffies_vid_out = cur_jiffies;
	dev->out_seq_offset = dev->out_seq_count + 1;
	dev->out_seq_count = 0;
	dev->out_seq_resync = false;
	}
	numerator = dev->timeperframe_vid_out.numerator;
	denominator = dev->timeperframe_vid_out.denominator;

	if (dev->field_out == V4L2_FIELD_ALTERNATE)
	denominator *= 2;

	/* Calculate the number of jiffies since we started streaming */
	jiffies_since_start = cur_jiffies - dev->jiffies_vid_out;
	/* Get the number of buffers streamed since the start */
	buffers_since_start = (u64)jiffies_since_start * denominator +
	(HZ * numerator) / 2;
	do_div(buffers_since_start, HZ * numerator);

	/*
	* After more than 0xf0000000 (rounded down to a multiple of
	* 'jiffies-per-day' to ease jiffies_to_msecs calculation)
	* jiffies have passed since we started streaming reset the
	* counters and keep track of the sequence offset.
	*/
	if (jiffies_since_start > JIFFIES_RESYNC) {
	dev->jiffies_vid_out = cur_jiffies;
	dev->out_seq_offset = buffers_since_start;
	buffers_since_start = 0;
	}
	dev->out_seq_count = buffers_since_start + dev->out_seq_offset;
	dev->vid_out_seq_count = dev->out_seq_count - dev->vid_out_seq_start;
	dev->vbi_out_seq_count = dev->out_seq_count - dev->vbi_out_seq_start;

	vivid_thread_vid_out_tick(dev);
	mutex_unlock(&dev->mutex);

	/*
	* Calculate the number of 'numerators' streamed since we started,
	* not including the current buffer.
	*/
	numerators_since_start = buffers_since_start * numerator;

	/* And the number of jiffies since we started */
	jiffies_since_start = jiffies - dev->jiffies_vid_out;

	/* Increase by the 'numerator' of one buffer */
	numerators_since_start += numerator;
	/*
	* Calculate when that next buffer is supposed to start
	* in jiffies since we started streaming.
	*/
	next_jiffies_since_start = numerators_since_start * HZ +
	denominator / 2;
	do_div(next_jiffies_since_start, denominator);
	/* If it is in the past, then just schedule asap */
	if (next_jiffies_since_start < jiffies_since_start)
	next_jiffies_since_start = jiffies_since_start;

	wait_jiffies = next_jiffies_since_start - jiffies_since_start;
	schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
	}
	dprintk(dev, 1, "Video Output Thread End\n");
	return 0;
	}

	static void vivid_grab_controls(struct vivid_dev *dev, bool grab)
	{
	v4l2_ctrl_grab(dev->ctrl_has_crop_out, grab);
	v4l2_ctrl_grab(dev->ctrl_has_compose_out, grab);
	v4l2_ctrl_grab(dev->ctrl_has_scaler_out, grab);
	v4l2_ctrl_grab(dev->ctrl_tx_mode, grab);
	v4l2_ctrl_grab(dev->ctrl_tx_rgb_range, grab);
	}

	int vivid_start_generating_vid_out(struct vivid_dev dev, bool pstreaming)
	{
	dprintk(dev, 1, "%s\n", __func__);

	if (dev->kthread_vid_out) {
	u32 seq_count = dev->out_seq_count + dev->seq_wrap * 128;

	if (pstreaming == &dev->vid_out_streaming)
	dev->vid_out_seq_start = seq_count;
	else
	dev->vbi_out_seq_start = seq_count;
	*pstreaming = true;
	return 0;
	}

	/* Resets frame counters */
	dev->jiffies_vid_out = jiffies;
	dev->vid_out_seq_start = dev->seq_wrap * 128;
	dev->vbi_out_seq_start = dev->seq_wrap * 128;

	dev->kthread_vid_out = kthread_run(vivid_thread_vid_out, dev,
	"%s-vid-out", dev->v4l2_dev.name);

	if (IS_ERR(dev->kthread_vid_out)) {
	v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
	return PTR_ERR(dev->kthread_vid_out);
	}
	*pstreaming = true;
	vivid_grab_controls(dev, true);

	dprintk(dev, 1, "returning from %s\n", __func__);
	return 0;
	}

	void vivid_stop_generating_vid_out(struct vivid_dev dev, bool pstreaming)
	{
	dprintk(dev, 1, "%s\n", __func__);

	if (dev->kthread_vid_out == NULL)
	return;

	*pstreaming = false;
	if (pstreaming == &dev->vid_out_streaming) {
	/* Release all active buffers */
	while (!list_empty(&dev->vid_out_active)) {
	struct vivid_buffer *buf;

	buf = list_entry(dev->vid_out_active.next,
	struct vivid_buffer, list);
	list_del(&buf->list);
	vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
	dprintk(dev, 2, "vid_out buffer %d done\n",
	buf->vb.vb2_buf.index);
	}
	}

	if (pstreaming == &dev->vbi_out_streaming) {
	while (!list_empty(&dev->vbi_out_active)) {
	struct vivid_buffer *buf;

	buf = list_entry(dev->vbi_out_active.next,
	struct vivid_buffer, list);
	list_del(&buf->list);
	vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
	dprintk(dev, 2, "vbi_out buffer %d done\n",
	buf->vb.vb2_buf.index);
	}
	}

	if (dev->vid_out_streaming \|\| dev->vbi_out_streaming)
	return;

	/* shutdown control thread */
	vivid_grab_controls(dev, false);
	mutex_unlock(&dev->mutex);
	kthread_stop(dev->kthread_vid_out);
	dev->kthread_vid_out = NULL;
	mutex_lock(&dev->mutex);
	}