1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * vivid-kthread-out.h - video/vbi output thread support functions.
4  *
5  * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
6  */
7 
8 #include <linux/module.h>
9 #include <linux/errno.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/sched.h>
13 #include <linux/slab.h>
14 #include <linux/font.h>
15 #include <linux/mutex.h>
16 #include <linux/videodev2.h>
17 #include <linux/kthread.h>
18 #include <linux/freezer.h>
19 #include <linux/random.h>
20 #include <linux/v4l2-dv-timings.h>
21 #include <asm/div64.h>
22 #include <media/videobuf2-vmalloc.h>
23 #include <media/v4l2-dv-timings.h>
24 #include <media/v4l2-ioctl.h>
25 #include <media/v4l2-fh.h>
26 #include <media/v4l2-event.h>
27 
28 #include "vivid-core.h"
29 #include "vivid-vid-common.h"
30 #include "vivid-vid-cap.h"
31 #include "vivid-vid-out.h"
32 #include "vivid-radio-common.h"
33 #include "vivid-radio-rx.h"
34 #include "vivid-radio-tx.h"
35 #include "vivid-sdr-cap.h"
36 #include "vivid-vbi-cap.h"
37 #include "vivid-vbi-out.h"
38 #include "vivid-osd.h"
39 #include "vivid-ctrls.h"
40 #include "vivid-kthread-out.h"
41 
vivid_thread_vid_out_tick(struct vivid_dev * dev)42 static void vivid_thread_vid_out_tick(struct vivid_dev *dev)
43 {
44 	struct vivid_buffer *vid_out_buf = NULL;
45 	struct vivid_buffer *vbi_out_buf = NULL;
46 
47 	dprintk(dev, 1, "Video Output Thread Tick\n");
48 
49 	/* Drop a certain percentage of buffers. */
50 	if (dev->perc_dropped_buffers &&
51 	    prandom_u32_max(100) < dev->perc_dropped_buffers)
52 		return;
53 
54 	spin_lock(&dev->slock);
55 	/*
56 	 * Only dequeue buffer if there is at least one more pending.
57 	 * This makes video loopback possible.
58 	 */
59 	if (!list_empty(&dev->vid_out_active) &&
60 	    !list_is_singular(&dev->vid_out_active)) {
61 		vid_out_buf = list_entry(dev->vid_out_active.next,
62 					 struct vivid_buffer, list);
63 		list_del(&vid_out_buf->list);
64 	}
65 	if (!list_empty(&dev->vbi_out_active) &&
66 	    (dev->field_out != V4L2_FIELD_ALTERNATE ||
67 	     (dev->vbi_out_seq_count & 1))) {
68 		vbi_out_buf = list_entry(dev->vbi_out_active.next,
69 					 struct vivid_buffer, list);
70 		list_del(&vbi_out_buf->list);
71 	}
72 	spin_unlock(&dev->slock);
73 
74 	if (!vid_out_buf && !vbi_out_buf)
75 		return;
76 
77 	if (vid_out_buf) {
78 		v4l2_ctrl_request_setup(vid_out_buf->vb.vb2_buf.req_obj.req,
79 					&dev->ctrl_hdl_vid_out);
80 		v4l2_ctrl_request_complete(vid_out_buf->vb.vb2_buf.req_obj.req,
81 					   &dev->ctrl_hdl_vid_out);
82 		vid_out_buf->vb.sequence = dev->vid_out_seq_count;
83 		if (dev->field_out == V4L2_FIELD_ALTERNATE) {
84 			/*
85 			 * The sequence counter counts frames, not fields.
86 			 * So divide by two.
87 			 */
88 			vid_out_buf->vb.sequence /= 2;
89 		}
90 		vid_out_buf->vb.vb2_buf.timestamp =
91 			ktime_get_ns() + dev->time_wrap_offset;
92 		vb2_buffer_done(&vid_out_buf->vb.vb2_buf, dev->dqbuf_error ?
93 				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
94 		dprintk(dev, 2, "vid_out buffer %d done\n",
95 			vid_out_buf->vb.vb2_buf.index);
96 	}
97 
98 	if (vbi_out_buf) {
99 		v4l2_ctrl_request_setup(vbi_out_buf->vb.vb2_buf.req_obj.req,
100 					&dev->ctrl_hdl_vbi_out);
101 		v4l2_ctrl_request_complete(vbi_out_buf->vb.vb2_buf.req_obj.req,
102 					   &dev->ctrl_hdl_vbi_out);
103 		if (dev->stream_sliced_vbi_out)
104 			vivid_sliced_vbi_out_process(dev, vbi_out_buf);
105 
106 		vbi_out_buf->vb.sequence = dev->vbi_out_seq_count;
107 		vbi_out_buf->vb.vb2_buf.timestamp =
108 			ktime_get_ns() + dev->time_wrap_offset;
109 		vb2_buffer_done(&vbi_out_buf->vb.vb2_buf, dev->dqbuf_error ?
110 				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
111 		dprintk(dev, 2, "vbi_out buffer %d done\n",
112 			vbi_out_buf->vb.vb2_buf.index);
113 	}
114 	dev->dqbuf_error = false;
115 }
116 
vivid_thread_vid_out(void * data)117 static int vivid_thread_vid_out(void *data)
118 {
119 	struct vivid_dev *dev = data;
120 	u64 numerators_since_start;
121 	u64 buffers_since_start;
122 	u64 next_jiffies_since_start;
123 	unsigned long jiffies_since_start;
124 	unsigned long cur_jiffies;
125 	unsigned wait_jiffies;
126 	unsigned numerator;
127 	unsigned denominator;
128 
129 	dprintk(dev, 1, "Video Output Thread Start\n");
130 
131 	set_freezable();
132 
133 	/* Resets frame counters */
134 	dev->out_seq_offset = 0;
135 	if (dev->seq_wrap)
136 		dev->out_seq_count = 0xffffff80U;
137 	dev->jiffies_vid_out = jiffies;
138 	dev->vid_out_seq_start = dev->vbi_out_seq_start = 0;
139 	dev->out_seq_resync = false;
140 
141 	for (;;) {
142 		try_to_freeze();
143 		if (kthread_should_stop())
144 			break;
145 
146 		mutex_lock(&dev->mutex);
147 		cur_jiffies = jiffies;
148 		if (dev->out_seq_resync) {
149 			dev->jiffies_vid_out = cur_jiffies;
150 			dev->out_seq_offset = dev->out_seq_count + 1;
151 			dev->out_seq_count = 0;
152 			dev->out_seq_resync = false;
153 		}
154 		numerator = dev->timeperframe_vid_out.numerator;
155 		denominator = dev->timeperframe_vid_out.denominator;
156 
157 		if (dev->field_out == V4L2_FIELD_ALTERNATE)
158 			denominator *= 2;
159 
160 		/* Calculate the number of jiffies since we started streaming */
161 		jiffies_since_start = cur_jiffies - dev->jiffies_vid_out;
162 		/* Get the number of buffers streamed since the start */
163 		buffers_since_start = (u64)jiffies_since_start * denominator +
164 				      (HZ * numerator) / 2;
165 		do_div(buffers_since_start, HZ * numerator);
166 
167 		/*
168 		 * After more than 0xf0000000 (rounded down to a multiple of
169 		 * 'jiffies-per-day' to ease jiffies_to_msecs calculation)
170 		 * jiffies have passed since we started streaming reset the
171 		 * counters and keep track of the sequence offset.
172 		 */
173 		if (jiffies_since_start > JIFFIES_RESYNC) {
174 			dev->jiffies_vid_out = cur_jiffies;
175 			dev->out_seq_offset = buffers_since_start;
176 			buffers_since_start = 0;
177 		}
178 		dev->out_seq_count = buffers_since_start + dev->out_seq_offset;
179 		dev->vid_out_seq_count = dev->out_seq_count - dev->vid_out_seq_start;
180 		dev->vbi_out_seq_count = dev->out_seq_count - dev->vbi_out_seq_start;
181 
182 		vivid_thread_vid_out_tick(dev);
183 		mutex_unlock(&dev->mutex);
184 
185 		/*
186 		 * Calculate the number of 'numerators' streamed since we started,
187 		 * not including the current buffer.
188 		 */
189 		numerators_since_start = buffers_since_start * numerator;
190 
191 		/* And the number of jiffies since we started */
192 		jiffies_since_start = jiffies - dev->jiffies_vid_out;
193 
194 		/* Increase by the 'numerator' of one buffer */
195 		numerators_since_start += numerator;
196 		/*
197 		 * Calculate when that next buffer is supposed to start
198 		 * in jiffies since we started streaming.
199 		 */
200 		next_jiffies_since_start = numerators_since_start * HZ +
201 					   denominator / 2;
202 		do_div(next_jiffies_since_start, denominator);
203 		/* If it is in the past, then just schedule asap */
204 		if (next_jiffies_since_start < jiffies_since_start)
205 			next_jiffies_since_start = jiffies_since_start;
206 
207 		wait_jiffies = next_jiffies_since_start - jiffies_since_start;
208 		schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
209 	}
210 	dprintk(dev, 1, "Video Output Thread End\n");
211 	return 0;
212 }
213 
vivid_grab_controls(struct vivid_dev * dev,bool grab)214 static void vivid_grab_controls(struct vivid_dev *dev, bool grab)
215 {
216 	v4l2_ctrl_grab(dev->ctrl_has_crop_out, grab);
217 	v4l2_ctrl_grab(dev->ctrl_has_compose_out, grab);
218 	v4l2_ctrl_grab(dev->ctrl_has_scaler_out, grab);
219 	v4l2_ctrl_grab(dev->ctrl_tx_mode, grab);
220 	v4l2_ctrl_grab(dev->ctrl_tx_rgb_range, grab);
221 }
222 
vivid_start_generating_vid_out(struct vivid_dev * dev,bool * pstreaming)223 int vivid_start_generating_vid_out(struct vivid_dev *dev, bool *pstreaming)
224 {
225 	dprintk(dev, 1, "%s\n", __func__);
226 
227 	if (dev->kthread_vid_out) {
228 		u32 seq_count = dev->out_seq_count + dev->seq_wrap * 128;
229 
230 		if (pstreaming == &dev->vid_out_streaming)
231 			dev->vid_out_seq_start = seq_count;
232 		else
233 			dev->vbi_out_seq_start = seq_count;
234 		*pstreaming = true;
235 		return 0;
236 	}
237 
238 	/* Resets frame counters */
239 	dev->jiffies_vid_out = jiffies;
240 	dev->vid_out_seq_start = dev->seq_wrap * 128;
241 	dev->vbi_out_seq_start = dev->seq_wrap * 128;
242 
243 	dev->kthread_vid_out = kthread_run(vivid_thread_vid_out, dev,
244 			"%s-vid-out", dev->v4l2_dev.name);
245 
246 	if (IS_ERR(dev->kthread_vid_out)) {
247 		int err = PTR_ERR(dev->kthread_vid_out);
248 
249 		dev->kthread_vid_out = NULL;
250 		v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
251 		return err;
252 	}
253 	*pstreaming = true;
254 	vivid_grab_controls(dev, true);
255 
256 	dprintk(dev, 1, "returning from %s\n", __func__);
257 	return 0;
258 }
259 
vivid_stop_generating_vid_out(struct vivid_dev * dev,bool * pstreaming)260 void vivid_stop_generating_vid_out(struct vivid_dev *dev, bool *pstreaming)
261 {
262 	dprintk(dev, 1, "%s\n", __func__);
263 
264 	if (dev->kthread_vid_out == NULL)
265 		return;
266 
267 	*pstreaming = false;
268 	if (pstreaming == &dev->vid_out_streaming) {
269 		/* Release all active buffers */
270 		while (!list_empty(&dev->vid_out_active)) {
271 			struct vivid_buffer *buf;
272 
273 			buf = list_entry(dev->vid_out_active.next,
274 					 struct vivid_buffer, list);
275 			list_del(&buf->list);
276 			v4l2_ctrl_request_complete(buf->vb.vb2_buf.req_obj.req,
277 						   &dev->ctrl_hdl_vid_out);
278 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
279 			dprintk(dev, 2, "vid_out buffer %d done\n",
280 				buf->vb.vb2_buf.index);
281 		}
282 	}
283 
284 	if (pstreaming == &dev->vbi_out_streaming) {
285 		while (!list_empty(&dev->vbi_out_active)) {
286 			struct vivid_buffer *buf;
287 
288 			buf = list_entry(dev->vbi_out_active.next,
289 					 struct vivid_buffer, list);
290 			list_del(&buf->list);
291 			v4l2_ctrl_request_complete(buf->vb.vb2_buf.req_obj.req,
292 						   &dev->ctrl_hdl_vbi_out);
293 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
294 			dprintk(dev, 2, "vbi_out buffer %d done\n",
295 				buf->vb.vb2_buf.index);
296 		}
297 	}
298 
299 	if (dev->vid_out_streaming || dev->vbi_out_streaming)
300 		return;
301 
302 	/* shutdown control thread */
303 	vivid_grab_controls(dev, false);
304 	mutex_unlock(&dev->mutex);
305 	kthread_stop(dev->kthread_vid_out);
306 	dev->kthread_vid_out = NULL;
307 	mutex_lock(&dev->mutex);
308 }
309