1 /*
2  * vivid-kthread-out.h - video/vbi output thread support functions.
3  *
4  * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
5  *
6  * This program is free software; you may redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 of the License.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
11  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
12  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
13  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
14  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
15  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
16  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
17  * SOFTWARE.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/errno.h>
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/font.h>
27 #include <linux/mutex.h>
28 #include <linux/videodev2.h>
29 #include <linux/kthread.h>
30 #include <linux/freezer.h>
31 #include <linux/random.h>
32 #include <linux/v4l2-dv-timings.h>
33 #include <asm/div64.h>
34 #include <media/videobuf2-vmalloc.h>
35 #include <media/v4l2-dv-timings.h>
36 #include <media/v4l2-ioctl.h>
37 #include <media/v4l2-fh.h>
38 #include <media/v4l2-event.h>
39 
40 #include "vivid-core.h"
41 #include "vivid-vid-common.h"
42 #include "vivid-vid-cap.h"
43 #include "vivid-vid-out.h"
44 #include "vivid-radio-common.h"
45 #include "vivid-radio-rx.h"
46 #include "vivid-radio-tx.h"
47 #include "vivid-sdr-cap.h"
48 #include "vivid-vbi-cap.h"
49 #include "vivid-vbi-out.h"
50 #include "vivid-osd.h"
51 #include "vivid-ctrls.h"
52 #include "vivid-kthread-out.h"
53 
vivid_thread_vid_out_tick(struct vivid_dev * dev)54 static void vivid_thread_vid_out_tick(struct vivid_dev *dev)
55 {
56 	struct vivid_buffer *vid_out_buf = NULL;
57 	struct vivid_buffer *vbi_out_buf = NULL;
58 
59 	dprintk(dev, 1, "Video Output Thread Tick\n");
60 
61 	/* Drop a certain percentage of buffers. */
62 	if (dev->perc_dropped_buffers &&
63 	    prandom_u32_max(100) < dev->perc_dropped_buffers)
64 		return;
65 
66 	spin_lock(&dev->slock);
67 	/*
68 	 * Only dequeue buffer if there is at least one more pending.
69 	 * This makes video loopback possible.
70 	 */
71 	if (!list_empty(&dev->vid_out_active) &&
72 	    !list_is_singular(&dev->vid_out_active)) {
73 		vid_out_buf = list_entry(dev->vid_out_active.next,
74 					 struct vivid_buffer, list);
75 		list_del(&vid_out_buf->list);
76 	}
77 	if (!list_empty(&dev->vbi_out_active) &&
78 	    (dev->field_out != V4L2_FIELD_ALTERNATE ||
79 	     (dev->vbi_out_seq_count & 1))) {
80 		vbi_out_buf = list_entry(dev->vbi_out_active.next,
81 					 struct vivid_buffer, list);
82 		list_del(&vbi_out_buf->list);
83 	}
84 	spin_unlock(&dev->slock);
85 
86 	if (!vid_out_buf && !vbi_out_buf)
87 		return;
88 
89 	if (vid_out_buf) {
90 		vid_out_buf->vb.sequence = dev->vid_out_seq_count;
91 		if (dev->field_out == V4L2_FIELD_ALTERNATE) {
92 			/*
93 			 * The sequence counter counts frames, not fields.
94 			 * So divide by two.
95 			 */
96 			vid_out_buf->vb.sequence /= 2;
97 		}
98 		v4l2_get_timestamp(&vid_out_buf->vb.timestamp);
99 		vid_out_buf->vb.timestamp.tv_sec += dev->time_wrap_offset;
100 		vb2_buffer_done(&vid_out_buf->vb.vb2_buf, dev->dqbuf_error ?
101 				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
102 		dprintk(dev, 2, "vid_out buffer %d done\n",
103 			vid_out_buf->vb.vb2_buf.index);
104 	}
105 
106 	if (vbi_out_buf) {
107 		if (dev->stream_sliced_vbi_out)
108 			vivid_sliced_vbi_out_process(dev, vbi_out_buf);
109 
110 		vbi_out_buf->vb.sequence = dev->vbi_out_seq_count;
111 		v4l2_get_timestamp(&vbi_out_buf->vb.timestamp);
112 		vbi_out_buf->vb.timestamp.tv_sec += dev->time_wrap_offset;
113 		vb2_buffer_done(&vbi_out_buf->vb.vb2_buf, dev->dqbuf_error ?
114 				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
115 		dprintk(dev, 2, "vbi_out buffer %d done\n",
116 			vbi_out_buf->vb.vb2_buf.index);
117 	}
118 	dev->dqbuf_error = false;
119 }
120 
vivid_thread_vid_out(void * data)121 static int vivid_thread_vid_out(void *data)
122 {
123 	struct vivid_dev *dev = data;
124 	u64 numerators_since_start;
125 	u64 buffers_since_start;
126 	u64 next_jiffies_since_start;
127 	unsigned long jiffies_since_start;
128 	unsigned long cur_jiffies;
129 	unsigned wait_jiffies;
130 	unsigned numerator;
131 	unsigned denominator;
132 
133 	dprintk(dev, 1, "Video Output Thread Start\n");
134 
135 	set_freezable();
136 
137 	/* Resets frame counters */
138 	dev->out_seq_offset = 0;
139 	if (dev->seq_wrap)
140 		dev->out_seq_count = 0xffffff80U;
141 	dev->jiffies_vid_out = jiffies;
142 	dev->vid_out_seq_start = dev->vbi_out_seq_start = 0;
143 	dev->out_seq_resync = false;
144 
145 	for (;;) {
146 		try_to_freeze();
147 		if (kthread_should_stop())
148 			break;
149 
150 		mutex_lock(&dev->mutex);
151 		cur_jiffies = jiffies;
152 		if (dev->out_seq_resync) {
153 			dev->jiffies_vid_out = cur_jiffies;
154 			dev->out_seq_offset = dev->out_seq_count + 1;
155 			dev->out_seq_count = 0;
156 			dev->out_seq_resync = false;
157 		}
158 		numerator = dev->timeperframe_vid_out.numerator;
159 		denominator = dev->timeperframe_vid_out.denominator;
160 
161 		if (dev->field_out == V4L2_FIELD_ALTERNATE)
162 			denominator *= 2;
163 
164 		/* Calculate the number of jiffies since we started streaming */
165 		jiffies_since_start = cur_jiffies - dev->jiffies_vid_out;
166 		/* Get the number of buffers streamed since the start */
167 		buffers_since_start = (u64)jiffies_since_start * denominator +
168 				      (HZ * numerator) / 2;
169 		do_div(buffers_since_start, HZ * numerator);
170 
171 		/*
172 		 * After more than 0xf0000000 (rounded down to a multiple of
173 		 * 'jiffies-per-day' to ease jiffies_to_msecs calculation)
174 		 * jiffies have passed since we started streaming reset the
175 		 * counters and keep track of the sequence offset.
176 		 */
177 		if (jiffies_since_start > JIFFIES_RESYNC) {
178 			dev->jiffies_vid_out = cur_jiffies;
179 			dev->out_seq_offset = buffers_since_start;
180 			buffers_since_start = 0;
181 		}
182 		dev->out_seq_count = buffers_since_start + dev->out_seq_offset;
183 		dev->vid_out_seq_count = dev->out_seq_count - dev->vid_out_seq_start;
184 		dev->vbi_out_seq_count = dev->out_seq_count - dev->vbi_out_seq_start;
185 
186 		vivid_thread_vid_out_tick(dev);
187 		mutex_unlock(&dev->mutex);
188 
189 		/*
190 		 * Calculate the number of 'numerators' streamed since we started,
191 		 * not including the current buffer.
192 		 */
193 		numerators_since_start = buffers_since_start * numerator;
194 
195 		/* And the number of jiffies since we started */
196 		jiffies_since_start = jiffies - dev->jiffies_vid_out;
197 
198 		/* Increase by the 'numerator' of one buffer */
199 		numerators_since_start += numerator;
200 		/*
201 		 * Calculate when that next buffer is supposed to start
202 		 * in jiffies since we started streaming.
203 		 */
204 		next_jiffies_since_start = numerators_since_start * HZ +
205 					   denominator / 2;
206 		do_div(next_jiffies_since_start, denominator);
207 		/* If it is in the past, then just schedule asap */
208 		if (next_jiffies_since_start < jiffies_since_start)
209 			next_jiffies_since_start = jiffies_since_start;
210 
211 		wait_jiffies = next_jiffies_since_start - jiffies_since_start;
212 		schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
213 	}
214 	dprintk(dev, 1, "Video Output Thread End\n");
215 	return 0;
216 }
217 
vivid_grab_controls(struct vivid_dev * dev,bool grab)218 static void vivid_grab_controls(struct vivid_dev *dev, bool grab)
219 {
220 	v4l2_ctrl_grab(dev->ctrl_has_crop_out, grab);
221 	v4l2_ctrl_grab(dev->ctrl_has_compose_out, grab);
222 	v4l2_ctrl_grab(dev->ctrl_has_scaler_out, grab);
223 	v4l2_ctrl_grab(dev->ctrl_tx_mode, grab);
224 	v4l2_ctrl_grab(dev->ctrl_tx_rgb_range, grab);
225 }
226 
vivid_start_generating_vid_out(struct vivid_dev * dev,bool * pstreaming)227 int vivid_start_generating_vid_out(struct vivid_dev *dev, bool *pstreaming)
228 {
229 	dprintk(dev, 1, "%s\n", __func__);
230 
231 	if (dev->kthread_vid_out) {
232 		u32 seq_count = dev->out_seq_count + dev->seq_wrap * 128;
233 
234 		if (pstreaming == &dev->vid_out_streaming)
235 			dev->vid_out_seq_start = seq_count;
236 		else
237 			dev->vbi_out_seq_start = seq_count;
238 		*pstreaming = true;
239 		return 0;
240 	}
241 
242 	/* Resets frame counters */
243 	dev->jiffies_vid_out = jiffies;
244 	dev->vid_out_seq_start = dev->seq_wrap * 128;
245 	dev->vbi_out_seq_start = dev->seq_wrap * 128;
246 
247 	dev->kthread_vid_out = kthread_run(vivid_thread_vid_out, dev,
248 			"%s-vid-out", dev->v4l2_dev.name);
249 
250 	if (IS_ERR(dev->kthread_vid_out)) {
251 		v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
252 		return PTR_ERR(dev->kthread_vid_out);
253 	}
254 	*pstreaming = true;
255 	vivid_grab_controls(dev, true);
256 
257 	dprintk(dev, 1, "returning from %s\n", __func__);
258 	return 0;
259 }
260 
vivid_stop_generating_vid_out(struct vivid_dev * dev,bool * pstreaming)261 void vivid_stop_generating_vid_out(struct vivid_dev *dev, bool *pstreaming)
262 {
263 	dprintk(dev, 1, "%s\n", __func__);
264 
265 	if (dev->kthread_vid_out == NULL)
266 		return;
267 
268 	*pstreaming = false;
269 	if (pstreaming == &dev->vid_out_streaming) {
270 		/* Release all active buffers */
271 		while (!list_empty(&dev->vid_out_active)) {
272 			struct vivid_buffer *buf;
273 
274 			buf = list_entry(dev->vid_out_active.next,
275 					 struct vivid_buffer, list);
276 			list_del(&buf->list);
277 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
278 			dprintk(dev, 2, "vid_out buffer %d done\n",
279 				buf->vb.vb2_buf.index);
280 		}
281 	}
282 
283 	if (pstreaming == &dev->vbi_out_streaming) {
284 		while (!list_empty(&dev->vbi_out_active)) {
285 			struct vivid_buffer *buf;
286 
287 			buf = list_entry(dev->vbi_out_active.next,
288 					 struct vivid_buffer, list);
289 			list_del(&buf->list);
290 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
291 			dprintk(dev, 2, "vbi_out buffer %d done\n",
292 				buf->vb.vb2_buf.index);
293 		}
294 	}
295 
296 	if (dev->vid_out_streaming || dev->vbi_out_streaming)
297 		return;
298 
299 	/* shutdown control thread */
300 	vivid_grab_controls(dev, false);
301 	mutex_unlock(&dev->mutex);
302 	kthread_stop(dev->kthread_vid_out);
303 	dev->kthread_vid_out = NULL;
304 	mutex_lock(&dev->mutex);
305 }
306