sound/sh/sh_dac_audio.c

   1 /*
   2  * sh_dac_audio.c - SuperH DAC audio driver for ALSA
   3  *
   4  * Copyright (c) 2009 by Rafael Ignacio Zurita <rizurita@yahoo.com>
   5  *
   6  *
   7  * Based on sh_dac_audio.c (Copyright (C) 2004, 2005 by Andriy Skulysh)
   8  *
   9  *   This program is free software; you can redistribute it and/or modify
  10  *   it under the terms of the GNU General Public License as published by
  11  *   the Free Software Foundation; either version 2 of the License, or
  12  *   (at your option) any later version.
  13  *
  14  *   This program is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *   GNU General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU General Public License
  20  *   along with this program; if not, write to the Free Software
  21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  22  *
  23  */
  24
  25 #include <linux/hrtimer.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/io.h>
  28 #include <linux/platform_device.h>
  29 #include <sound/core.h>
  30 #include <sound/initval.h>
  31 #include <sound/pcm.h>
  32 #include <sound/sh_dac_audio.h>
  33 #include <asm/clock.h>
  34 #include <asm/hd64461.h>
  35 #include <mach/hp6xx.h>
  36 #include <cpu/dac.h>
  37
  38 MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>");
  39 MODULE_DESCRIPTION("SuperH DAC audio driver");
  40 MODULE_LICENSE("GPL");
  41 MODULE_SUPPORTED_DEVICE("{{SuperH DAC audio support}}");
  42
  43 /* Module Parameters */
  44 static int index = SNDRV_DEFAULT_IDX1;
  45 static char *id = SNDRV_DEFAULT_STR1;
  46 module_param(index, int, 0444);
  47 MODULE_PARM_DESC(index, "Index value for SuperH DAC audio.");
  48 module_param(id, charp, 0444);
  49 MODULE_PARM_DESC(id, "ID string for SuperH DAC audio.");
  50
  51 /* main struct */
  52 struct snd_sh_dac {
  53         struct snd_card *card;
  54         struct snd_pcm_substream *substream;
  55         struct hrtimer hrtimer;
  56         ktime_t wakeups_per_second;
  57
  58         int rate;
  59         int empty;
  60         char *data_buffer, *buffer_begin, *buffer_end;
  61         int processed; /* bytes proccesed, to compare with period_size */
  62         int buffer_size;
  63         struct dac_audio_pdata *pdata;
  64 };
  65
  66
  67 static void dac_audio_start_timer(struct snd_sh_dac *chip)
  68 {
  69         hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
  70                       HRTIMER_MODE_REL);
  71 }
  72
  73 static void dac_audio_stop_timer(struct snd_sh_dac *chip)
  74 {
  75         hrtimer_cancel(&chip->hrtimer);
  76 }
  77
  78 static void dac_audio_reset(struct snd_sh_dac *chip)
  79 {
  80         dac_audio_stop_timer(chip);
  81         chip->buffer_begin = chip->buffer_end = chip->data_buffer;
  82         chip->processed = 0;
  83         chip->empty = 1;
  84 }
  85
  86 static void dac_audio_set_rate(struct snd_sh_dac *chip)
  87 {
  88         chip->wakeups_per_second = ktime_set(0, 1000000000 / chip->rate);
  89 }
  90
  91
  92 /* PCM INTERFACE */
  93
  94 static struct snd_pcm_hardware snd_sh_dac_pcm_hw = {
  95         .info                   = (SNDRV_PCM_INFO_MMAP |
  96                                         SNDRV_PCM_INFO_MMAP_VALID |
  97                                         SNDRV_PCM_INFO_INTERLEAVED |
  98                                         SNDRV_PCM_INFO_HALF_DUPLEX),
  99         .formats                = SNDRV_PCM_FMTBIT_U8,
 100         .rates                  = SNDRV_PCM_RATE_8000,
 101         .rate_min               = 8000,
 102         .rate_max               = 8000,
 103         .channels_min           = 1,
 104         .channels_max           = 1,
 105         .buffer_bytes_max       = (48*1024),
 106         .period_bytes_min       = 1,
 107         .period_bytes_max       = (48*1024),
 108         .periods_min            = 1,
 109         .periods_max            = 1024,
 110 };
 111
 112 static int snd_sh_dac_pcm_open(struct snd_pcm_substream *substream)
 113 {
 114         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 115         struct snd_pcm_runtime *runtime = substream->runtime;
 116
 117         runtime->hw = snd_sh_dac_pcm_hw;
 118
 119         chip->substream = substream;
 120         chip->buffer_begin = chip->buffer_end = chip->data_buffer;
 121         chip->processed = 0;
 122         chip->empty = 1;
 123
 124         chip->pdata->start(chip->pdata);
 125
 126         return 0;
 127 }
 128
 129 static int snd_sh_dac_pcm_close(struct snd_pcm_substream *substream)
 130 {
 131         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 132
 133         chip->substream = NULL;
 134
 135         dac_audio_stop_timer(chip);
 136         chip->pdata->stop(chip->pdata);
 137
 138         return 0;
 139 }
 140
 141 static int snd_sh_dac_pcm_hw_params(struct snd_pcm_substream *substream,
 142                                 struct snd_pcm_hw_params *hw_params)
 143 {
 144         return snd_pcm_lib_malloc_pages(substream,
 145                         params_buffer_bytes(hw_params));
 146 }
 147
 148 static int snd_sh_dac_pcm_hw_free(struct snd_pcm_substream *substream)
 149 {
 150         return snd_pcm_lib_free_pages(substream);
 151 }
 152
 153 static int snd_sh_dac_pcm_prepare(struct snd_pcm_substream *substream)
 154 {
 155         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 156         struct snd_pcm_runtime *runtime = chip->substream->runtime;
 157
 158         chip->buffer_size = runtime->buffer_size;
 159         memset(chip->data_buffer, 0, chip->pdata->buffer_size);
 160
 161         return 0;
 162 }
 163
 164 static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 165 {
 166         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 167
 168         switch (cmd) {
 169         case SNDRV_PCM_TRIGGER_START:
 170                 dac_audio_start_timer(chip);
 171                 break;
 172         case SNDRV_PCM_TRIGGER_STOP:
 173                 chip->buffer_begin = chip->buffer_end = chip->data_buffer;
 174                 chip->processed = 0;
 175                 chip->empty = 1;
 176                 dac_audio_stop_timer(chip);
 177                 break;
 178         default:
 179                  return -EINVAL;
 180         }
 181
 182         return 0;
 183 }
 184
 185 static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream, int channel,
 186         snd_pcm_uframes_t pos, void __user *src, snd_pcm_uframes_t count)
 187 {
 188         /* channel is not used (interleaved data) */
 189         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 190         struct snd_pcm_runtime *runtime = substream->runtime;
 191         ssize_t b_count = frames_to_bytes(runtime , count);
 192         ssize_t b_pos = frames_to_bytes(runtime , pos);
 193
 194         if (count < 0)
 195                 return -EINVAL;
 196
 197         if (!count)
 198                 return 0;
 199
 200         memcpy_toio(chip->data_buffer + b_pos, src, b_count);
 201         chip->buffer_end = chip->data_buffer + b_pos + b_count;
 202
 203         if (chip->empty) {
 204                 chip->empty = 0;
 205                 dac_audio_start_timer(chip);
 206         }
 207
 208         return 0;
 209 }
 210
 211 static int snd_sh_dac_pcm_silence(struct snd_pcm_substream *substream,
 212                                   int channel, snd_pcm_uframes_t pos,
 213                                   snd_pcm_uframes_t count)
 214 {
 215         /* channel is not used (interleaved data) */
 216         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 217         struct snd_pcm_runtime *runtime = substream->runtime;
 218         ssize_t b_count = frames_to_bytes(runtime , count);
 219         ssize_t b_pos = frames_to_bytes(runtime , pos);
 220
 221         if (count < 0)
 222                 return -EINVAL;
 223
 224         if (!count)
 225                 return 0;
 226
 227         memset_io(chip->data_buffer + b_pos, 0, b_count);
 228         chip->buffer_end = chip->data_buffer + b_pos + b_count;
 229
 230         if (chip->empty) {
 231                 chip->empty = 0;
 232                 dac_audio_start_timer(chip);
 233         }
 234
 235         return 0;
 236 }
 237
 238 static
 239 snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream)
 240 {
 241         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 242         int pointer = chip->buffer_begin - chip->data_buffer;
 243
 244         return pointer;
 245 }
 246
 247 /* pcm ops */
 248 static struct snd_pcm_ops snd_sh_dac_pcm_ops = {
 249         .open           = snd_sh_dac_pcm_open,
 250         .close          = snd_sh_dac_pcm_close,
 251         .ioctl          = snd_pcm_lib_ioctl,
 252         .hw_params      = snd_sh_dac_pcm_hw_params,
 253         .hw_free        = snd_sh_dac_pcm_hw_free,
 254         .prepare        = snd_sh_dac_pcm_prepare,
 255         .trigger        = snd_sh_dac_pcm_trigger,
 256         .pointer        = snd_sh_dac_pcm_pointer,
 257         .copy           = snd_sh_dac_pcm_copy,
 258         .silence        = snd_sh_dac_pcm_silence,
 259         .mmap           = snd_pcm_lib_mmap_iomem,
 260 };
 261
 262 static int __devinit snd_sh_dac_pcm(struct snd_sh_dac *chip, int device)
 263 {
 264         int err;
 265         struct snd_pcm *pcm;
 266
 267         /* device should be always 0 for us */
 268         err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm);
 269         if (err < 0)
 270                 return err;
 271
 272         pcm->private_data = chip;
 273         strcpy(pcm->name, "SH_DAC PCM");
 274         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops);
 275
 276         /* buffer size=48K */
 277         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
 278                                           snd_dma_continuous_data(GFP_KERNEL),
 279                                                         48 * 1024,
 280                                                         48 * 1024);
 281
 282         return 0;
 283 }
 284 /* END OF PCM INTERFACE */
 285
 286
 287 /* driver .remove  --  destructor */
 288 static int snd_sh_dac_remove(struct platform_device *devptr)
 289 {
 290         snd_card_free(platform_get_drvdata(devptr));
 291         platform_set_drvdata(devptr, NULL);
 292
 293         return 0;
 294 }
 295
 296 /* free -- it has been defined by create */
 297 static int snd_sh_dac_free(struct snd_sh_dac *chip)
 298 {
 299         /* release the data */
 300         kfree(chip->data_buffer);
 301         kfree(chip);
 302
 303         return 0;
 304 }
 305
 306 static int snd_sh_dac_dev_free(struct snd_device *device)
 307 {
 308         struct snd_sh_dac *chip = device->device_data;
 309
 310         return snd_sh_dac_free(chip);
 311 }
 312
 313 static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
 314 {
 315         struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac,
 316                                                hrtimer);
 317         struct snd_pcm_runtime *runtime = chip->substream->runtime;
 318         ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size);
 319
 320         if (!chip->empty) {
 321                 sh_dac_output(*chip->buffer_begin, chip->pdata->channel);
 322                 chip->buffer_begin++;
 323
 324                 chip->processed++;
 325                 if (chip->processed >= b_ps) {
 326                         chip->processed -= b_ps;
 327                         snd_pcm_period_elapsed(chip->substream);
 328                 }
 329
 330                 if (chip->buffer_begin == (chip->data_buffer +
 331                                            chip->buffer_size - 1))
 332                         chip->buffer_begin = chip->data_buffer;
 333
 334                 if (chip->buffer_begin == chip->buffer_end)
 335                         chip->empty = 1;
 336
 337         }
 338
 339         if (!chip->empty)
 340                 hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
 341                               HRTIMER_MODE_REL);
 342
 343         return HRTIMER_NORESTART;
 344 }
 345
 346 /* create  --  chip-specific constructor for the cards components */
 347 static int __devinit snd_sh_dac_create(struct snd_card *card,
 348                                        struct platform_device *devptr,
 349                                        struct snd_sh_dac **rchip)
 350 {
 351         struct snd_sh_dac *chip;
 352         int err;
 353
 354         static struct snd_device_ops ops = {
 355                    .dev_free = snd_sh_dac_dev_free,
 356         };
 357
 358         *rchip = NULL;
 359
 360         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 361         if (chip == NULL)
 362                 return -ENOMEM;
 363
 364         chip->card = card;
 365
 366         hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 367         chip->hrtimer.function = sh_dac_audio_timer;
 368
 369         dac_audio_reset(chip);
 370         chip->rate = 8000;
 371         dac_audio_set_rate(chip);
 372
 373         chip->pdata = devptr->dev.platform_data;
 374
 375         chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL);
 376         if (chip->data_buffer == NULL) {
 377                 kfree(chip);
 378                 return -ENOMEM;
 379         }
 380
 381         err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
 382         if (err < 0) {
 383                 snd_sh_dac_free(chip);
 384                 return err;
 385         }
 386
 387         *rchip = chip;
 388
 389         return 0;
 390 }
 391
 392 /* driver .probe  --  constructor */
 393 static int __devinit snd_sh_dac_probe(struct platform_device *devptr)
 394 {
 395         struct snd_sh_dac *chip;
 396         struct snd_card *card;
 397         int err;
 398
 399         err = snd_card_create(index, id, THIS_MODULE, 0, &card);
 400         if (err < 0) {
 401                         snd_printk(KERN_ERR "cannot allocate the card\n");
 402                         return err;
 403         }
 404
 405         err = snd_sh_dac_create(card, devptr, &chip);
 406         if (err < 0)
 407                 goto probe_error;
 408
 409         err = snd_sh_dac_pcm(chip, 0);
 410         if (err < 0)
 411                 goto probe_error;
 412
 413         strcpy(card->driver, "snd_sh_dac");
 414         strcpy(card->shortname, "SuperH DAC audio driver");
 415         printk(KERN_INFO "%s %s", card->longname, card->shortname);
 416
 417         err = snd_card_register(card);
 418         if (err < 0)
 419                 goto probe_error;
 420
 421         snd_printk("ALSA driver for SuperH DAC audio");
 422
 423         platform_set_drvdata(devptr, card);
 424         return 0;
 425
 426 probe_error:
 427         snd_card_free(card);
 428         return err;
 429 }
 430
 431 /*
 432  * "driver" definition
 433  */
 434 static struct platform_driver driver = {
 435         .probe  = snd_sh_dac_probe,
 436         .remove = snd_sh_dac_remove,
 437         .driver = {
 438                 .name = "dac_audio",
 439         },
 440 };
 441
 442 static int __init sh_dac_init(void)
 443 {
 444         return platform_driver_register(&driver);
 445 }
 446
 447 static void __exit sh_dac_exit(void)
 448 {
 449         platform_driver_unregister(&driver);
 450 }
 451
 452 module_init(sh_dac_init);
 453 module_exit(sh_dac_exit);