kernel/drivers/media/platform/vivid/vivid-sdr-cap.c

   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
  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
 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
 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
 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
 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
 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 */
 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
 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
 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
 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
 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
 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
 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
 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
 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 }