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