1 /*
2 * vivid-sdr-cap.c - software defined radio 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/errno.h>
21 #include <linux/kernel.h>
22 #include <linux/delay.h>
23 #include <linux/kthread.h>
24 #include <linux/freezer.h>
25 #include <linux/videodev2.h>
26 #include <linux/v4l2-dv-timings.h>
27 #include <media/v4l2-common.h>
28 #include <media/v4l2-event.h>
29 #include <media/v4l2-dv-timings.h>
30 #include <linux/fixp-arith.h>
31
32 #include "vivid-core.h"
33 #include "vivid-ctrls.h"
34 #include "vivid-sdr-cap.h"
35
36 static const struct v4l2_frequency_band bands_adc[] = {
37 {
38 .tuner = 0,
39 .type = V4L2_TUNER_ADC,
40 .index = 0,
41 .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
42 .rangelow = 300000,
43 .rangehigh = 300000,
44 },
45 {
46 .tuner = 0,
47 .type = V4L2_TUNER_ADC,
48 .index = 1,
49 .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
50 .rangelow = 900001,
51 .rangehigh = 2800000,
52 },
53 {
54 .tuner = 0,
55 .type = V4L2_TUNER_ADC,
56 .index = 2,
57 .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
58 .rangelow = 3200000,
59 .rangehigh = 3200000,
60 },
61 };
62
63 /* ADC band midpoints */
64 #define BAND_ADC_0 ((bands_adc[0].rangehigh + bands_adc[1].rangelow) / 2)
65 #define BAND_ADC_1 ((bands_adc[1].rangehigh + bands_adc[2].rangelow) / 2)
66
67 static const struct v4l2_frequency_band bands_fm[] = {
68 {
69 .tuner = 1,
70 .type = V4L2_TUNER_RF,
71 .index = 0,
72 .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
73 .rangelow = 50000000,
74 .rangehigh = 2000000000,
75 },
76 };
77
vivid_thread_sdr_cap_tick(struct vivid_dev * dev)78 static void vivid_thread_sdr_cap_tick(struct vivid_dev *dev)
79 {
80 struct vivid_buffer *sdr_cap_buf = NULL;
81
82 dprintk(dev, 1, "SDR Capture Thread Tick\n");
83
84 /* Drop a certain percentage of buffers. */
85 if (dev->perc_dropped_buffers &&
86 prandom_u32_max(100) < dev->perc_dropped_buffers)
87 return;
88
89 spin_lock(&dev->slock);
90 if (!list_empty(&dev->sdr_cap_active)) {
91 sdr_cap_buf = list_entry(dev->sdr_cap_active.next,
92 struct vivid_buffer, list);
93 list_del(&sdr_cap_buf->list);
94 }
95 spin_unlock(&dev->slock);
96
97 if (sdr_cap_buf) {
98 sdr_cap_buf->vb.v4l2_buf.sequence = dev->sdr_cap_seq_count;
99 vivid_sdr_cap_process(dev, sdr_cap_buf);
100 v4l2_get_timestamp(&sdr_cap_buf->vb.v4l2_buf.timestamp);
101 sdr_cap_buf->vb.v4l2_buf.timestamp.tv_sec += dev->time_wrap_offset;
102 vb2_buffer_done(&sdr_cap_buf->vb, dev->dqbuf_error ?
103 VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
104 dev->dqbuf_error = false;
105 }
106 }
107
vivid_thread_sdr_cap(void * data)108 static int vivid_thread_sdr_cap(void *data)
109 {
110 struct vivid_dev *dev = data;
111 u64 samples_since_start;
112 u64 buffers_since_start;
113 u64 next_jiffies_since_start;
114 unsigned long jiffies_since_start;
115 unsigned long cur_jiffies;
116 unsigned wait_jiffies;
117
118 dprintk(dev, 1, "SDR Capture Thread Start\n");
119
120 set_freezable();
121
122 /* Resets frame counters */
123 dev->sdr_cap_seq_offset = 0;
124 if (dev->seq_wrap)
125 dev->sdr_cap_seq_offset = 0xffffff80U;
126 dev->jiffies_sdr_cap = jiffies;
127 dev->sdr_cap_seq_resync = false;
128
129 for (;;) {
130 try_to_freeze();
131 if (kthread_should_stop())
132 break;
133
134 mutex_lock(&dev->mutex);
135 cur_jiffies = jiffies;
136 if (dev->sdr_cap_seq_resync) {
137 dev->jiffies_sdr_cap = cur_jiffies;
138 dev->sdr_cap_seq_offset = dev->sdr_cap_seq_count + 1;
139 dev->sdr_cap_seq_count = 0;
140 dev->sdr_cap_seq_resync = false;
141 }
142 /* Calculate the number of jiffies since we started streaming */
143 jiffies_since_start = cur_jiffies - dev->jiffies_sdr_cap;
144 /* Get the number of buffers streamed since the start */
145 buffers_since_start = (u64)jiffies_since_start * dev->sdr_adc_freq +
146 (HZ * SDR_CAP_SAMPLES_PER_BUF) / 2;
147 do_div(buffers_since_start, HZ * SDR_CAP_SAMPLES_PER_BUF);
148
149 /*
150 * After more than 0xf0000000 (rounded down to a multiple of
151 * 'jiffies-per-day' to ease jiffies_to_msecs calculation)
152 * jiffies have passed since we started streaming reset the
153 * counters and keep track of the sequence offset.
154 */
155 if (jiffies_since_start > JIFFIES_RESYNC) {
156 dev->jiffies_sdr_cap = cur_jiffies;
157 dev->sdr_cap_seq_offset = buffers_since_start;
158 buffers_since_start = 0;
159 }
160 dev->sdr_cap_seq_count = buffers_since_start + dev->sdr_cap_seq_offset;
161
162 vivid_thread_sdr_cap_tick(dev);
163 mutex_unlock(&dev->mutex);
164
165 /*
166 * Calculate the number of samples streamed since we started,
167 * not including the current buffer.
168 */
169 samples_since_start = buffers_since_start * SDR_CAP_SAMPLES_PER_BUF;
170
171 /* And the number of jiffies since we started */
172 jiffies_since_start = jiffies - dev->jiffies_sdr_cap;
173
174 /* Increase by the number of samples in one buffer */
175 samples_since_start += SDR_CAP_SAMPLES_PER_BUF;
176 /*
177 * Calculate when that next buffer is supposed to start
178 * in jiffies since we started streaming.
179 */
180 next_jiffies_since_start = samples_since_start * HZ +
181 dev->sdr_adc_freq / 2;
182 do_div(next_jiffies_since_start, dev->sdr_adc_freq);
183 /* If it is in the past, then just schedule asap */
184 if (next_jiffies_since_start < jiffies_since_start)
185 next_jiffies_since_start = jiffies_since_start;
186
187 wait_jiffies = next_jiffies_since_start - jiffies_since_start;
188 schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
189 }
190 dprintk(dev, 1, "SDR Capture Thread End\n");
191 return 0;
192 }
193
sdr_cap_queue_setup(struct vb2_queue * vq,const struct v4l2_format * fmt,unsigned * nbuffers,unsigned * nplanes,unsigned sizes[],void * alloc_ctxs[])194 static int sdr_cap_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
195 unsigned *nbuffers, unsigned *nplanes,
196 unsigned sizes[], void *alloc_ctxs[])
197 {
198 /* 2 = max 16-bit sample returned */
199 sizes[0] = SDR_CAP_SAMPLES_PER_BUF * 2;
200 *nplanes = 1;
201 return 0;
202 }
203
sdr_cap_buf_prepare(struct vb2_buffer * vb)204 static int sdr_cap_buf_prepare(struct vb2_buffer *vb)
205 {
206 struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
207 unsigned size = SDR_CAP_SAMPLES_PER_BUF * 2;
208
209 dprintk(dev, 1, "%s\n", __func__);
210
211 if (dev->buf_prepare_error) {
212 /*
213 * Error injection: test what happens if buf_prepare() returns
214 * an error.
215 */
216 dev->buf_prepare_error = false;
217 return -EINVAL;
218 }
219 if (vb2_plane_size(vb, 0) < size) {
220 dprintk(dev, 1, "%s data will not fit into plane (%lu < %u)\n",
221 __func__, vb2_plane_size(vb, 0), size);
222 return -EINVAL;
223 }
224 vb2_set_plane_payload(vb, 0, size);
225
226 return 0;
227 }
228
sdr_cap_buf_queue(struct vb2_buffer * vb)229 static void sdr_cap_buf_queue(struct vb2_buffer *vb)
230 {
231 struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
232 struct vivid_buffer *buf = container_of(vb, struct vivid_buffer, vb);
233
234 dprintk(dev, 1, "%s\n", __func__);
235
236 spin_lock(&dev->slock);
237 list_add_tail(&buf->list, &dev->sdr_cap_active);
238 spin_unlock(&dev->slock);
239 }
240
sdr_cap_start_streaming(struct vb2_queue * vq,unsigned count)241 static int sdr_cap_start_streaming(struct vb2_queue *vq, unsigned count)
242 {
243 struct vivid_dev *dev = vb2_get_drv_priv(vq);
244 int err = 0;
245
246 dprintk(dev, 1, "%s\n", __func__);
247 dev->sdr_cap_seq_count = 0;
248 if (dev->start_streaming_error) {
249 dev->start_streaming_error = false;
250 err = -EINVAL;
251 } else if (dev->kthread_sdr_cap == NULL) {
252 dev->kthread_sdr_cap = kthread_run(vivid_thread_sdr_cap, dev,
253 "%s-sdr-cap", dev->v4l2_dev.name);
254
255 if (IS_ERR(dev->kthread_sdr_cap)) {
256 v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
257 err = PTR_ERR(dev->kthread_sdr_cap);
258 dev->kthread_sdr_cap = NULL;
259 }
260 }
261 if (err) {
262 struct vivid_buffer *buf, *tmp;
263
264 list_for_each_entry_safe(buf, tmp, &dev->sdr_cap_active, list) {
265 list_del(&buf->list);
266 vb2_buffer_done(&buf->vb, VB2_BUF_STATE_QUEUED);
267 }
268 }
269 return err;
270 }
271
272 /* abort streaming and wait for last buffer */
sdr_cap_stop_streaming(struct vb2_queue * vq)273 static void sdr_cap_stop_streaming(struct vb2_queue *vq)
274 {
275 struct vivid_dev *dev = vb2_get_drv_priv(vq);
276
277 if (dev->kthread_sdr_cap == NULL)
278 return;
279
280 while (!list_empty(&dev->sdr_cap_active)) {
281 struct vivid_buffer *buf;
282
283 buf = list_entry(dev->sdr_cap_active.next, struct vivid_buffer, list);
284 list_del(&buf->list);
285 vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
286 }
287
288 /* shutdown control thread */
289 mutex_unlock(&dev->mutex);
290 kthread_stop(dev->kthread_sdr_cap);
291 dev->kthread_sdr_cap = NULL;
292 mutex_lock(&dev->mutex);
293 }
294
295 const struct vb2_ops vivid_sdr_cap_qops = {
296 .queue_setup = sdr_cap_queue_setup,
297 .buf_prepare = sdr_cap_buf_prepare,
298 .buf_queue = sdr_cap_buf_queue,
299 .start_streaming = sdr_cap_start_streaming,
300 .stop_streaming = sdr_cap_stop_streaming,
301 .wait_prepare = vb2_ops_wait_prepare,
302 .wait_finish = vb2_ops_wait_finish,
303 };
304
vivid_sdr_enum_freq_bands(struct file * file,void * fh,struct v4l2_frequency_band * band)305 int vivid_sdr_enum_freq_bands(struct file *file, void *fh, struct v4l2_frequency_band *band)
306 {
307 switch (band->tuner) {
308 case 0:
309 if (band->index >= ARRAY_SIZE(bands_adc))
310 return -EINVAL;
311 *band = bands_adc[band->index];
312 return 0;
313 case 1:
314 if (band->index >= ARRAY_SIZE(bands_fm))
315 return -EINVAL;
316 *band = bands_fm[band->index];
317 return 0;
318 default:
319 return -EINVAL;
320 }
321 }
322
vivid_sdr_g_frequency(struct file * file,void * fh,struct v4l2_frequency * vf)323 int vivid_sdr_g_frequency(struct file *file, void *fh, struct v4l2_frequency *vf)
324 {
325 struct vivid_dev *dev = video_drvdata(file);
326
327 switch (vf->tuner) {
328 case 0:
329 vf->frequency = dev->sdr_adc_freq;
330 vf->type = V4L2_TUNER_ADC;
331 return 0;
332 case 1:
333 vf->frequency = dev->sdr_fm_freq;
334 vf->type = V4L2_TUNER_RF;
335 return 0;
336 default:
337 return -EINVAL;
338 }
339 }
340
vivid_sdr_s_frequency(struct file * file,void * fh,const struct v4l2_frequency * vf)341 int vivid_sdr_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf)
342 {
343 struct vivid_dev *dev = video_drvdata(file);
344 unsigned freq = vf->frequency;
345 unsigned band;
346
347 switch (vf->tuner) {
348 case 0:
349 if (vf->type != V4L2_TUNER_ADC)
350 return -EINVAL;
351 if (freq < BAND_ADC_0)
352 band = 0;
353 else if (freq < BAND_ADC_1)
354 band = 1;
355 else
356 band = 2;
357
358 freq = clamp_t(unsigned, freq,
359 bands_adc[band].rangelow,
360 bands_adc[band].rangehigh);
361
362 if (vb2_is_streaming(&dev->vb_sdr_cap_q) &&
363 freq != dev->sdr_adc_freq) {
364 /* resync the thread's timings */
365 dev->sdr_cap_seq_resync = true;
366 }
367 dev->sdr_adc_freq = freq;
368 return 0;
369 case 1:
370 if (vf->type != V4L2_TUNER_RF)
371 return -EINVAL;
372 dev->sdr_fm_freq = clamp_t(unsigned, freq,
373 bands_fm[0].rangelow,
374 bands_fm[0].rangehigh);
375 return 0;
376 default:
377 return -EINVAL;
378 }
379 }
380
vivid_sdr_g_tuner(struct file * file,void * fh,struct v4l2_tuner * vt)381 int vivid_sdr_g_tuner(struct file *file, void *fh, struct v4l2_tuner *vt)
382 {
383 switch (vt->index) {
384 case 0:
385 strlcpy(vt->name, "ADC", sizeof(vt->name));
386 vt->type = V4L2_TUNER_ADC;
387 vt->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
388 vt->rangelow = bands_adc[0].rangelow;
389 vt->rangehigh = bands_adc[2].rangehigh;
390 return 0;
391 case 1:
392 strlcpy(vt->name, "RF", sizeof(vt->name));
393 vt->type = V4L2_TUNER_RF;
394 vt->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
395 vt->rangelow = bands_fm[0].rangelow;
396 vt->rangehigh = bands_fm[0].rangehigh;
397 return 0;
398 default:
399 return -EINVAL;
400 }
401 }
402
vivid_sdr_s_tuner(struct file * file,void * fh,const struct v4l2_tuner * vt)403 int vivid_sdr_s_tuner(struct file *file, void *fh, const struct v4l2_tuner *vt)
404 {
405 if (vt->index > 1)
406 return -EINVAL;
407 return 0;
408 }
409
vidioc_enum_fmt_sdr_cap(struct file * file,void * fh,struct v4l2_fmtdesc * f)410 int vidioc_enum_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_fmtdesc *f)
411 {
412 if (f->index)
413 return -EINVAL;
414 f->pixelformat = V4L2_SDR_FMT_CU8;
415 strlcpy(f->description, "IQ U8", sizeof(f->description));
416 return 0;
417 }
418
vidioc_g_fmt_sdr_cap(struct file * file,void * fh,struct v4l2_format * f)419 int vidioc_g_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_format *f)
420 {
421 f->fmt.sdr.pixelformat = V4L2_SDR_FMT_CU8;
422 f->fmt.sdr.buffersize = SDR_CAP_SAMPLES_PER_BUF * 2;
423 memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
424 return 0;
425 }
426
427 #define FIXP_N (15)
428 #define FIXP_FRAC (1 << FIXP_N)
429 #define FIXP_2PI ((int)(2 * 3.141592653589 * FIXP_FRAC))
430
vivid_sdr_cap_process(struct vivid_dev * dev,struct vivid_buffer * buf)431 void vivid_sdr_cap_process(struct vivid_dev *dev, struct vivid_buffer *buf)
432 {
433 u8 *vbuf = vb2_plane_vaddr(&buf->vb, 0);
434 unsigned long i;
435 unsigned long plane_size = vb2_plane_size(&buf->vb, 0);
436 s32 src_phase_step;
437 s32 mod_phase_step;
438 s32 fixp_i;
439 s32 fixp_q;
440
441 /*
442 * TODO: Generated beep tone goes very crackly when sample rate is
443 * increased to ~1Msps or more. That is because of huge rounding error
444 * of phase angle caused by used cosine implementation.
445 */
446
447 /* calculate phase step */
448 #define BEEP_FREQ 1000 /* 1kHz beep */
449 src_phase_step = DIV_ROUND_CLOSEST(FIXP_2PI * BEEP_FREQ,
450 dev->sdr_adc_freq);
451
452 for (i = 0; i < plane_size; i += 2) {
453 mod_phase_step = fixp_cos32_rad(dev->sdr_fixp_src_phase,
454 FIXP_2PI) >> (31 - FIXP_N);
455
456 dev->sdr_fixp_src_phase += src_phase_step;
457 dev->sdr_fixp_mod_phase += mod_phase_step / 4;
458
459 /*
460 * Transfer phases to [0 / 2xPI] in order to avoid variable
461 * overflow and make it suitable for cosine implementation
462 * used, which does not support negative angles.
463 */
464 while (dev->sdr_fixp_mod_phase < FIXP_2PI)
465 dev->sdr_fixp_mod_phase += FIXP_2PI;
466 while (dev->sdr_fixp_mod_phase > FIXP_2PI)
467 dev->sdr_fixp_mod_phase -= FIXP_2PI;
468
469 while (dev->sdr_fixp_src_phase > FIXP_2PI)
470 dev->sdr_fixp_src_phase -= FIXP_2PI;
471
472 fixp_i = fixp_cos32_rad(dev->sdr_fixp_mod_phase, FIXP_2PI);
473 fixp_q = fixp_sin32_rad(dev->sdr_fixp_mod_phase, FIXP_2PI);
474
475 /* Normalize fraction values represented with 32 bit precision
476 * to fixed point representation with FIXP_N bits */
477 fixp_i >>= (31 - FIXP_N);
478 fixp_q >>= (31 - FIXP_N);
479
480 /* convert 'fixp float' to u8 */
481 /* u8 = X * 127.5f + 127.5f; where X is float [-1.0 / +1.0] */
482 fixp_i = fixp_i * 1275 + FIXP_FRAC * 1275;
483 fixp_q = fixp_q * 1275 + FIXP_FRAC * 1275;
484 *vbuf++ = DIV_ROUND_CLOSEST(fixp_i, FIXP_FRAC * 10);
485 *vbuf++ = DIV_ROUND_CLOSEST(fixp_q, FIXP_FRAC * 10);
486 }
487 }
488