LXR linux/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
  31#include "vivid-core.h"
  32#include "vivid-ctrls.h"
  33#include "vivid-sdr-cap.h"
  34
  35static const struct v4l2_frequency_band bands_adc[] = {
  36        {
  37                .tuner = 0,
  38                .type = V4L2_TUNER_ADC,
  39                .index = 0,
  40                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
  41                .rangelow   =  300000,
  42                .rangehigh  =  300000,
  43        },
  44        {
  45                .tuner = 0,
  46                .type = V4L2_TUNER_ADC,
  47                .index = 1,
  48                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
  49                .rangelow   =  900001,
  50                .rangehigh  = 2800000,
  51        },
  52        {
  53                .tuner = 0,
  54                .type = V4L2_TUNER_ADC,
  55                .index = 2,
  56                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
  57                .rangelow   = 3200000,
  58                .rangehigh  = 3200000,
  59        },
  60};
  61
  62/* ADC band midpoints */
  63#define BAND_ADC_0 ((bands_adc[0].rangehigh + bands_adc[1].rangelow) / 2)
  64#define BAND_ADC_1 ((bands_adc[1].rangehigh + bands_adc[2].rangelow) / 2)
  65
  66static const struct v4l2_frequency_band bands_fm[] = {
  67        {
  68                .tuner = 1,
  69                .type = V4L2_TUNER_RF,
  70                .index = 0,
  71                .capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
  72                .rangelow   =    50000000,
  73                .rangehigh  =  2000000000,
  74        },
  75};
  76
  77static void vivid_thread_sdr_cap_tick(struct vivid_dev *dev)
  78{
  79        struct vivid_buffer *sdr_cap_buf = NULL;
  80
  81        dprintk(dev, 1, "SDR Capture Thread Tick\n");
  82
  83        /* Drop a certain percentage of buffers. */
  84        if (dev->perc_dropped_buffers &&
  85            prandom_u32_max(100) < dev->perc_dropped_buffers)
  86                return;
  87
  88        spin_lock(&dev->slock);
  89        if (!list_empty(&dev->sdr_cap_active)) {
  90                sdr_cap_buf = list_entry(dev->sdr_cap_active.next,
  91                                         struct vivid_buffer, list);
  92                list_del(&sdr_cap_buf->list);
  93        }
  94        spin_unlock(&dev->slock);
  95
  96        if (sdr_cap_buf) {
  97                sdr_cap_buf->vb.v4l2_buf.sequence = dev->sdr_cap_seq_count;
  98                vivid_sdr_cap_process(dev, sdr_cap_buf);
  99                v4l2_get_timestamp(&sdr_cap_buf->vb.v4l2_buf.timestamp);
 100                sdr_cap_buf->vb.v4l2_buf.timestamp.tv_sec += dev->time_wrap_offset;
 101                vb2_buffer_done(&sdr_cap_buf->vb, dev->dqbuf_error ?
 102                                VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
 103                dev->dqbuf_error = false;
 104        }
 105}
 106
 107static int vivid_thread_sdr_cap(void *data)
 108{
 109        struct vivid_dev *dev = data;
 110        u64 samples_since_start;
 111        u64 buffers_since_start;
 112        u64 next_jiffies_since_start;
 113        unsigned long jiffies_since_start;
 114        unsigned long cur_jiffies;
 115        unsigned wait_jiffies;
 116
 117        dprintk(dev, 1, "SDR Capture Thread Start\n");
 118
 119        set_freezable();
 120
 121        /* Resets frame counters */
 122        dev->sdr_cap_seq_offset = 0;
 123        if (dev->seq_wrap)
 124                dev->sdr_cap_seq_offset = 0xffffff80U;
 125        dev->jiffies_sdr_cap = jiffies;
 126        dev->sdr_cap_seq_resync = false;
 127
 128        for (;;) {
 129                try_to_freeze();
 130                if (kthread_should_stop())
 131                        break;
 132
 133                mutex_lock(&dev->mutex);
 134                cur_jiffies = jiffies;
 135                if (dev->sdr_cap_seq_resync) {
 136                        dev->jiffies_sdr_cap = cur_jiffies;
 137                        dev->sdr_cap_seq_offset = dev->sdr_cap_seq_count + 1;
 138                        dev->sdr_cap_seq_count = 0;
 139                        dev->sdr_cap_seq_resync = false;
 140                }
 141                /* Calculate the number of jiffies since we started streaming */
 142                jiffies_since_start = cur_jiffies - dev->jiffies_sdr_cap;
 143                /* Get the number of buffers streamed since the start */
 144                buffers_since_start = (u64)jiffies_since_start * dev->sdr_adc_freq +
 145                                      (HZ * SDR_CAP_SAMPLES_PER_BUF) / 2;
 146                do_div(buffers_since_start, HZ * SDR_CAP_SAMPLES_PER_BUF);
 147
 148                /*
 149                 * After more than 0xf0000000 (rounded down to a multiple of
 150                 * 'jiffies-per-day' to ease jiffies_to_msecs calculation)
 151                 * jiffies have passed since we started streaming reset the
 152                 * counters and keep track of the sequence offset.
 153                 */
 154                if (jiffies_since_start > JIFFIES_RESYNC) {
 155                        dev->jiffies_sdr_cap = cur_jiffies;
 156                        dev->sdr_cap_seq_offset = buffers_since_start;
 157                        buffers_since_start = 0;
 158                }
 159                dev->sdr_cap_seq_count = buffers_since_start + dev->sdr_cap_seq_offset;
 160
 161                vivid_thread_sdr_cap_tick(dev);
 162                mutex_unlock(&dev->mutex);
 163
 164                /*
 165                 * Calculate the number of samples streamed since we started,
 166                 * not including the current buffer.
 167                 */
 168                samples_since_start = buffers_since_start * SDR_CAP_SAMPLES_PER_BUF;
 169
 170                /* And the number of jiffies since we started */
 171                jiffies_since_start = jiffies - dev->jiffies_sdr_cap;
 172
 173                /* Increase by the number of samples in one buffer */
 174                samples_since_start += SDR_CAP_SAMPLES_PER_BUF;
 175                /*
 176                 * Calculate when that next buffer is supposed to start
 177                 * in jiffies since we started streaming.
 178                 */
 179                next_jiffies_since_start = samples_since_start * HZ +
 180                                           dev->sdr_adc_freq / 2;
 181                do_div(next_jiffies_since_start, dev->sdr_adc_freq);
 182                /* If it is in the past, then just schedule asap */
 183                if (next_jiffies_since_start < jiffies_since_start)
 184                        next_jiffies_since_start = jiffies_since_start;
 185
 186                wait_jiffies = next_jiffies_since_start - jiffies_since_start;
 187                schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
 188        }
 189        dprintk(dev, 1, "SDR Capture Thread End\n");
 190        return 0;
 191}
 192
 193static int sdr_cap_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
 194                       unsigned *nbuffers, unsigned *nplanes,
 195                       unsigned sizes[], void *alloc_ctxs[])
 196{
 197        /* 2 = max 16-bit sample returned */
 198        sizes[0] = SDR_CAP_SAMPLES_PER_BUF * 2;
 199        *nplanes = 1;
 200        return 0;
 201}
 202
 203static int sdr_cap_buf_prepare(struct vb2_buffer *vb)
 204{
 205        struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
 206        unsigned size = SDR_CAP_SAMPLES_PER_BUF * 2;
 207
 208        dprintk(dev, 1, "%s\n", __func__);
 209
 210        if (dev->buf_prepare_error) {
 211                /*
 212                 * Error injection: test what happens if buf_prepare() returns
 213                 * an error.
 214                 */
 215                dev->buf_prepare_error = false;
 216                return -EINVAL;
 217        }
 218        if (vb2_plane_size(vb, 0) < size) {
 219                dprintk(dev, 1, "%s data will not fit into plane (%lu < %u)\n",
 220                                __func__, vb2_plane_size(vb, 0), size);
 221                return -EINVAL;
 222        }
 223        vb2_set_plane_payload(vb, 0, size);
 224
 225        return 0;
 226}
 227
 228static void sdr_cap_buf_queue(struct vb2_buffer *vb)
 229{
 230        struct vivid_dev *dev = vb2_get_drv_priv(vb->vb2_queue);
 231        struct vivid_buffer *buf = container_of(vb, struct vivid_buffer, vb);
 232
 233        dprintk(dev, 1, "%s\n", __func__);
 234
 235        spin_lock(&dev->slock);
 236        list_add_tail(&buf->list, &dev->sdr_cap_active);
 237        spin_unlock(&dev->slock);
 238}
 239
 240static int sdr_cap_start_streaming(struct vb2_queue *vq, unsigned count)
 241{
 242        struct vivid_dev *dev = vb2_get_drv_priv(vq);
 243        int err = 0;
 244
 245        dprintk(dev, 1, "%s\n", __func__);
 246        dev->sdr_cap_seq_count = 0;
 247        if (dev->start_streaming_error) {
 248                dev->start_streaming_error = false;
 249                err = -EINVAL;
 250        } else if (dev->kthread_sdr_cap == NULL) {
 251                dev->kthread_sdr_cap = kthread_run(vivid_thread_sdr_cap, dev,
 252                                "%s-sdr-cap", dev->v4l2_dev.name);
 253
 254                if (IS_ERR(dev->kthread_sdr_cap)) {
 255                        v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
 256                        err = PTR_ERR(dev->kthread_sdr_cap);
 257                        dev->kthread_sdr_cap = NULL;
 258                }
 259        }
 260        if (err) {
 261                struct vivid_buffer *buf, *tmp;
 262
 263                list_for_each_entry_safe(buf, tmp, &dev->sdr_cap_active, list) {
 264                        list_del(&buf->list);
 265                        vb2_buffer_done(&buf->vb, VB2_BUF_STATE_QUEUED);
 266                }
 267        }
 268        return err;
 269}
 270
 271/* abort streaming and wait for last buffer */
 272static void sdr_cap_stop_streaming(struct vb2_queue *vq)
 273{
 274        struct vivid_dev *dev = vb2_get_drv_priv(vq);
 275
 276        if (dev->kthread_sdr_cap == NULL)
 277                return;
 278
 279        while (!list_empty(&dev->sdr_cap_active)) {
 280                struct vivid_buffer *buf;
 281
 282                buf = list_entry(dev->sdr_cap_active.next, struct vivid_buffer, list);
 283                list_del(&buf->list);
 284                vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
 285        }
 286
 287        /* shutdown control thread */
 288        mutex_unlock(&dev->mutex);
 289        kthread_stop(dev->kthread_sdr_cap);
 290        dev->kthread_sdr_cap = NULL;
 291        mutex_lock(&dev->mutex);
 292}
 293
 294const struct vb2_ops vivid_sdr_cap_qops = {
 295        .queue_setup            = sdr_cap_queue_setup,
 296        .buf_prepare            = sdr_cap_buf_prepare,
 297        .buf_queue              = sdr_cap_buf_queue,
 298        .start_streaming        = sdr_cap_start_streaming,
 299        .stop_streaming         = sdr_cap_stop_streaming,
 300        .wait_prepare           = vb2_ops_wait_prepare,
 301        .wait_finish            = vb2_ops_wait_finish,
 302};
 303
 304int vivid_sdr_enum_freq_bands(struct file *file, void *fh, struct v4l2_frequency_band *band)
 305{
 306        switch (band->tuner) {
 307        case 0:
 308                if (band->index >= ARRAY_SIZE(bands_adc))
 309                        return -EINVAL;
 310                *band = bands_adc[band->index];
 311                return 0;
 312        case 1:
 313                if (band->index >= ARRAY_SIZE(bands_fm))
 314                        return -EINVAL;
 315                *band = bands_fm[band->index];
 316                return 0;
 317        default:
 318                return -EINVAL;
 319        }
 320}
 321
 322int vivid_sdr_g_frequency(struct file *file, void *fh, struct v4l2_frequency *vf)
 323{
 324        struct vivid_dev *dev = video_drvdata(file);
 325
 326        switch (vf->tuner) {
 327        case 0:
 328                vf->frequency = dev->sdr_adc_freq;
 329                vf->type = V4L2_TUNER_ADC;
 330                return 0;
 331        case 1:
 332                vf->frequency = dev->sdr_fm_freq;
 333                vf->type = V4L2_TUNER_RF;
 334                return 0;
 335        default:
 336                return -EINVAL;
 337        }
 338}
 339
 340int vivid_sdr_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf)
 341{
 342        struct vivid_dev *dev = video_drvdata(file);
 343        unsigned freq = vf->frequency;
 344        unsigned band;
 345
 346        switch (vf->tuner) {
 347        case 0:
 348                if (vf->type != V4L2_TUNER_ADC)
 349                        return -EINVAL;
 350                if (freq < BAND_ADC_0)
 351                        band = 0;
 352                else if (freq < BAND_ADC_1)
 353                        band = 1;
 354                else
 355                        band = 2;
 356
 357                freq = clamp_t(unsigned, freq,
 358                                bands_adc[band].rangelow,
 359                                bands_adc[band].rangehigh);
 360
 361                if (vb2_is_streaming(&dev->vb_sdr_cap_q) &&
 362                    freq != dev->sdr_adc_freq) {
 363                        /* resync the thread's timings */
 364                        dev->sdr_cap_seq_resync = true;
 365                }
 366                dev->sdr_adc_freq = freq;
 367                return 0;
 368        case 1:
 369                if (vf->type != V4L2_TUNER_RF)
 370                        return -EINVAL;
 371                dev->sdr_fm_freq = clamp_t(unsigned, freq,
 372                                bands_fm[0].rangelow,
 373                                bands_fm[0].rangehigh);
 374                return 0;
 375        default:
 376                return -EINVAL;
 377        }
 378}
 379
 380int vivid_sdr_g_tuner(struct file *file, void *fh, struct v4l2_tuner *vt)
 381{
 382        switch (vt->index) {
 383        case 0:
 384                strlcpy(vt->name, "ADC", sizeof(vt->name));
 385                vt->type = V4L2_TUNER_ADC;
 386                vt->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
 387                vt->rangelow = bands_adc[0].rangelow;
 388                vt->rangehigh = bands_adc[2].rangehigh;
 389                return 0;
 390        case 1:
 391                strlcpy(vt->name, "RF", sizeof(vt->name));
 392                vt->type = V4L2_TUNER_RF;
 393                vt->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
 394                vt->rangelow = bands_fm[0].rangelow;
 395                vt->rangehigh = bands_fm[0].rangehigh;
 396                return 0;
 397        default:
 398                return -EINVAL;
 399        }
 400}
 401
 402int vivid_sdr_s_tuner(struct file *file, void *fh, const struct v4l2_tuner *vt)
 403{
 404        if (vt->index > 1)
 405                return -EINVAL;
 406        return 0;
 407}
 408
 409int vidioc_enum_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_fmtdesc *f)
 410{
 411        if (f->index)
 412                return -EINVAL;
 413        f->pixelformat = V4L2_SDR_FMT_CU8;
 414        strlcpy(f->description, "IQ U8", sizeof(f->description));
 415        return 0;
 416}
 417
 418int vidioc_g_fmt_sdr_cap(struct file *file, void *fh, struct v4l2_format *f)
 419{
 420        f->fmt.sdr.pixelformat = V4L2_SDR_FMT_CU8;
 421        f->fmt.sdr.buffersize = SDR_CAP_SAMPLES_PER_BUF * 2;
 422        memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
 423        return 0;
 424}
 425
 426#define FIXP_FRAC    (1 << 15)
 427#define FIXP_PI      ((int)(FIXP_FRAC * 3.141592653589))
 428
 429/* cos() from cx88 driver: cx88-dsp.c */
 430static s32 fixp_cos(unsigned int x)
 431{
 432        u32 t2, t4, t6, t8;
 433        u16 period = x / FIXP_PI;
 434
 435        if (period % 2)
 436                return -fixp_cos(x - FIXP_PI);
 437        x = x % FIXP_PI;
 438        if (x > FIXP_PI/2)
 439                return -fixp_cos(FIXP_PI/2 - (x % (FIXP_PI/2)));
 440        /* Now x is between 0 and FIXP_PI/2.
 441         * To calculate cos(x) we use it's Taylor polinom. */
 442        t2 = x*x/FIXP_FRAC/2;
 443        t4 = t2*x/FIXP_FRAC*x/FIXP_FRAC/3/4;
 444        t6 = t4*x/FIXP_FRAC*x/FIXP_FRAC/5/6;
 445        t8 = t6*x/FIXP_FRAC*x/FIXP_FRAC/7/8;
 446        return FIXP_FRAC-t2+t4-t6+t8;
 447}
 448
 449static inline s32 fixp_sin(unsigned int x)
 450{
 451        return -fixp_cos(x + (FIXP_PI / 2));
 452}
 453
 454void vivid_sdr_cap_process(struct vivid_dev *dev, struct vivid_buffer *buf)
 455{
 456        u8 *vbuf = vb2_plane_vaddr(&buf->vb, 0);
 457        unsigned long i;
 458        unsigned long plane_size = vb2_plane_size(&buf->vb, 0);
 459        int fixp_src_phase_step, fixp_i, fixp_q;
 460
 461        /*
 462         * TODO: Generated beep tone goes very crackly when sample rate is
 463         * increased to ~1Msps or more. That is because of huge rounding error
 464         * of phase angle caused by used cosine implementation.
 465         */
 466
 467        /* calculate phase step */
 468        #define BEEP_FREQ 1000 /* 1kHz beep */
 469        fixp_src_phase_step = DIV_ROUND_CLOSEST(2 * FIXP_PI * BEEP_FREQ,
 470                        dev->sdr_adc_freq);
 471
 472        for (i = 0; i < plane_size; i += 2) {
 473                dev->sdr_fixp_mod_phase += fixp_cos(dev->sdr_fixp_src_phase);
 474                dev->sdr_fixp_src_phase += fixp_src_phase_step;
 475
 476                /*
 477                 * Transfer phases to [0 / 2xPI] in order to avoid variable
 478                 * overflow and make it suitable for cosine implementation
 479                 * used, which does not support negative angles.
 480                 */
 481                while (dev->sdr_fixp_mod_phase < (0 * FIXP_PI))
 482                        dev->sdr_fixp_mod_phase += (2 * FIXP_PI);
 483                while (dev->sdr_fixp_mod_phase > (2 * FIXP_PI))
 484                        dev->sdr_fixp_mod_phase -= (2 * FIXP_PI);
 485
 486                while (dev->sdr_fixp_src_phase > (2 * FIXP_PI))
 487                        dev->sdr_fixp_src_phase -= (2 * FIXP_PI);
 488
 489                fixp_i = fixp_cos(dev->sdr_fixp_mod_phase);
 490                fixp_q = fixp_sin(dev->sdr_fixp_mod_phase);
 491
 492                /* convert 'fixp float' to u8 */
 493                /* u8 = X * 127.5f + 127.5f; where X is float [-1.0 / +1.0] */
 494                fixp_i = fixp_i * 1275 + FIXP_FRAC * 1275;
 495                fixp_q = fixp_q * 1275 + FIXP_FRAC * 1275;
 496                *vbuf++ = DIV_ROUND_CLOSEST(fixp_i, FIXP_FRAC * 10);
 497                *vbuf++ = DIV_ROUND_CLOSEST(fixp_q, FIXP_FRAC * 10);
 498        }
 499}
 500