sound/sh/sh_dac_audio.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * sh_dac_audio.c - SuperH DAC audio driver for ALSA
   4  *
   5  * Copyright (c) 2009 by Rafael Ignacio Zurita <rizurita@yahoo.com>
   6  *
   7  * Based on sh_dac_audio.c (Copyright (C) 2004, 2005 by Andriy Skulysh)
   8  */
   9
  10 #include <linux/hrtimer.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/io.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/slab.h>
  15 #include <linux/module.h>
  16 #include <sound/core.h>
  17 #include <sound/initval.h>
  18 #include <sound/pcm.h>
  19 #include <sound/sh_dac_audio.h>
  20 #include <asm/clock.h>
  21 #include <asm/hd64461.h>
  22 #include <mach/hp6xx.h>
  23 #include <cpu/dac.h>
  24
  25 MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>");
  26 MODULE_DESCRIPTION("SuperH DAC audio driver");
  27 MODULE_LICENSE("GPL");
  28 MODULE_SUPPORTED_DEVICE("{{SuperH DAC audio support}}");
  29
  30 /* Module Parameters */
  31 static int index = SNDRV_DEFAULT_IDX1;
  32 static char *id = SNDRV_DEFAULT_STR1;
  33 module_param(index, int, 0444);
  34 MODULE_PARM_DESC(index, "Index value for SuperH DAC audio.");
  35 module_param(id, charp, 0444);
  36 MODULE_PARM_DESC(id, "ID string for SuperH DAC audio.");
  37
  38 /* main struct */
  39 struct snd_sh_dac {
  40         struct snd_card *card;
  41         struct snd_pcm_substream *substream;
  42         struct hrtimer hrtimer;
  43         ktime_t wakeups_per_second;
  44
  45         int rate;
  46         int empty;
  47         char *data_buffer, *buffer_begin, *buffer_end;
  48         int processed; /* bytes proccesed, to compare with period_size */
  49         int buffer_size;
  50         struct dac_audio_pdata *pdata;
  51 };
  52
  53
  54 static void dac_audio_start_timer(struct snd_sh_dac *chip)
  55 {
  56         hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
  57                       HRTIMER_MODE_REL);
  58 }
  59
  60 static void dac_audio_stop_timer(struct snd_sh_dac *chip)
  61 {
  62         hrtimer_cancel(&chip->hrtimer);
  63 }
  64
  65 static void dac_audio_reset(struct snd_sh_dac *chip)
  66 {
  67         dac_audio_stop_timer(chip);
  68         chip->buffer_begin = chip->buffer_end = chip->data_buffer;
  69         chip->processed = 0;
  70         chip->empty = 1;
  71 }
  72
  73 static void dac_audio_set_rate(struct snd_sh_dac *chip)
  74 {
  75         chip->wakeups_per_second = 1000000000 / chip->rate;
  76 }
  77
  78
  79 /* PCM INTERFACE */
  80
  81 static const struct snd_pcm_hardware snd_sh_dac_pcm_hw = {
  82         .info                   = (SNDRV_PCM_INFO_MMAP |
  83                                         SNDRV_PCM_INFO_MMAP_VALID |
  84                                         SNDRV_PCM_INFO_INTERLEAVED |
  85                                         SNDRV_PCM_INFO_HALF_DUPLEX),
  86         .formats                = SNDRV_PCM_FMTBIT_U8,
  87         .rates                  = SNDRV_PCM_RATE_8000,
  88         .rate_min               = 8000,
  89         .rate_max               = 8000,
  90         .channels_min           = 1,
  91         .channels_max           = 1,
  92         .buffer_bytes_max       = (48*1024),
  93         .period_bytes_min       = 1,
  94         .period_bytes_max       = (48*1024),
  95         .periods_min            = 1,
  96         .periods_max            = 1024,
  97 };
  98
  99 static int snd_sh_dac_pcm_open(struct snd_pcm_substream *substream)
 100 {
 101         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 102         struct snd_pcm_runtime *runtime = substream->runtime;
 103
 104         runtime->hw = snd_sh_dac_pcm_hw;
 105
 106         chip->substream = substream;
 107         chip->buffer_begin = chip->buffer_end = chip->data_buffer;
 108         chip->processed = 0;
 109         chip->empty = 1;
 110
 111         chip->pdata->start(chip->pdata);
 112
 113         return 0;
 114 }
 115
 116 static int snd_sh_dac_pcm_close(struct snd_pcm_substream *substream)
 117 {
 118         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 119
 120         chip->substream = NULL;
 121
 122         dac_audio_stop_timer(chip);
 123         chip->pdata->stop(chip->pdata);
 124
 125         return 0;
 126 }
 127
 128 static int snd_sh_dac_pcm_hw_params(struct snd_pcm_substream *substream,
 129                                 struct snd_pcm_hw_params *hw_params)
 130 {
 131         return snd_pcm_lib_malloc_pages(substream,
 132                         params_buffer_bytes(hw_params));
 133 }
 134
 135 static int snd_sh_dac_pcm_hw_free(struct snd_pcm_substream *substream)
 136 {
 137         return snd_pcm_lib_free_pages(substream);
 138 }
 139
 140 static int snd_sh_dac_pcm_prepare(struct snd_pcm_substream *substream)
 141 {
 142         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 143         struct snd_pcm_runtime *runtime = chip->substream->runtime;
 144
 145         chip->buffer_size = runtime->buffer_size;
 146         memset(chip->data_buffer, 0, chip->pdata->buffer_size);
 147
 148         return 0;
 149 }
 150
 151 static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 152 {
 153         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 154
 155         switch (cmd) {
 156         case SNDRV_PCM_TRIGGER_START:
 157                 dac_audio_start_timer(chip);
 158                 break;
 159         case SNDRV_PCM_TRIGGER_STOP:
 160                 chip->buffer_begin = chip->buffer_end = chip->data_buffer;
 161                 chip->processed = 0;
 162                 chip->empty = 1;
 163                 dac_audio_stop_timer(chip);
 164                 break;
 165         default:
 166                  return -EINVAL;
 167         }
 168
 169         return 0;
 170 }
 171
 172 static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream,
 173                                int channel, unsigned long pos,
 174                                void __user *src, unsigned long count)
 175 {
 176         /* channel is not used (interleaved data) */
 177         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 178         struct snd_pcm_runtime *runtime = substream->runtime;
 179
 180         if (copy_from_user_toio(chip->data_buffer + pos, src, count))
 181                 return -EFAULT;
 182         chip->buffer_end = chip->data_buffer + pos + count;
 183
 184         if (chip->empty) {
 185                 chip->empty = 0;
 186                 dac_audio_start_timer(chip);
 187         }
 188
 189         return 0;
 190 }
 191
 192 static int snd_sh_dac_pcm_copy_kernel(struct snd_pcm_substream *substream,
 193                                       int channel, unsigned long pos,
 194                                       void *src, unsigned long count)
 195 {
 196         /* channel is not used (interleaved data) */
 197         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 198         struct snd_pcm_runtime *runtime = substream->runtime;
 199
 200         memcpy_toio(chip->data_buffer + pos, src, count);
 201         chip->buffer_end = chip->data_buffer + pos + 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, unsigned long pos,
 213                                   unsigned long 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
 219         memset_io(chip->data_buffer + pos, 0, count);
 220         chip->buffer_end = chip->data_buffer + pos + count;
 221
 222         if (chip->empty) {
 223                 chip->empty = 0;
 224                 dac_audio_start_timer(chip);
 225         }
 226
 227         return 0;
 228 }
 229
 230 static
 231 snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream)
 232 {
 233         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 234         int pointer = chip->buffer_begin - chip->data_buffer;
 235
 236         return pointer;
 237 }
 238
 239 /* pcm ops */
 240 static const struct snd_pcm_ops snd_sh_dac_pcm_ops = {
 241         .open           = snd_sh_dac_pcm_open,
 242         .close          = snd_sh_dac_pcm_close,
 243         .ioctl          = snd_pcm_lib_ioctl,
 244         .hw_params      = snd_sh_dac_pcm_hw_params,
 245         .hw_free        = snd_sh_dac_pcm_hw_free,
 246         .prepare        = snd_sh_dac_pcm_prepare,
 247         .trigger        = snd_sh_dac_pcm_trigger,
 248         .pointer        = snd_sh_dac_pcm_pointer,
 249         .copy_user      = snd_sh_dac_pcm_copy,
 250         .copy_kernel    = snd_sh_dac_pcm_copy_kernel,
 251         .fill_silence   = snd_sh_dac_pcm_silence,
 252         .mmap           = snd_pcm_lib_mmap_iomem,
 253 };
 254
 255 static int snd_sh_dac_pcm(struct snd_sh_dac *chip, int device)
 256 {
 257         int err;
 258         struct snd_pcm *pcm;
 259
 260         /* device should be always 0 for us */
 261         err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm);
 262         if (err < 0)
 263                 return err;
 264
 265         pcm->private_data = chip;
 266         strcpy(pcm->name, "SH_DAC PCM");
 267         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops);
 268
 269         /* buffer size=48K */
 270         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
 271                                               NULL,
 272                                                         48 * 1024,
 273                                                         48 * 1024);
 274
 275         return 0;
 276 }
 277 /* END OF PCM INTERFACE */
 278
 279
 280 /* driver .remove  --  destructor */
 281 static int snd_sh_dac_remove(struct platform_device *devptr)
 282 {
 283         snd_card_free(platform_get_drvdata(devptr));
 284         return 0;
 285 }
 286
 287 /* free -- it has been defined by create */
 288 static int snd_sh_dac_free(struct snd_sh_dac *chip)
 289 {
 290         /* release the data */
 291         kfree(chip->data_buffer);
 292         kfree(chip);
 293
 294         return 0;
 295 }
 296
 297 static int snd_sh_dac_dev_free(struct snd_device *device)
 298 {
 299         struct snd_sh_dac *chip = device->device_data;
 300
 301         return snd_sh_dac_free(chip);
 302 }
 303
 304 static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
 305 {
 306         struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac,
 307                                                hrtimer);
 308         struct snd_pcm_runtime *runtime = chip->substream->runtime;
 309         ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size);
 310
 311         if (!chip->empty) {
 312                 sh_dac_output(*chip->buffer_begin, chip->pdata->channel);
 313                 chip->buffer_begin++;
 314
 315                 chip->processed++;
 316                 if (chip->processed >= b_ps) {
 317                         chip->processed -= b_ps;
 318                         snd_pcm_period_elapsed(chip->substream);
 319                 }
 320
 321                 if (chip->buffer_begin == (chip->data_buffer +
 322                                            chip->buffer_size - 1))
 323                         chip->buffer_begin = chip->data_buffer;
 324
 325                 if (chip->buffer_begin == chip->buffer_end)
 326                         chip->empty = 1;
 327
 328         }
 329
 330         if (!chip->empty)
 331                 hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
 332                               HRTIMER_MODE_REL);
 333
 334         return HRTIMER_NORESTART;
 335 }
 336
 337 /* create  --  chip-specific constructor for the cards components */
 338 static int snd_sh_dac_create(struct snd_card *card,
 339                              struct platform_device *devptr,
 340                              struct snd_sh_dac **rchip)
 341 {
 342         struct snd_sh_dac *chip;
 343         int err;
 344
 345         static struct snd_device_ops ops = {
 346                    .dev_free = snd_sh_dac_dev_free,
 347         };
 348
 349         *rchip = NULL;
 350
 351         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 352         if (chip == NULL)
 353                 return -ENOMEM;
 354
 355         chip->card = card;
 356
 357         hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 358         chip->hrtimer.function = sh_dac_audio_timer;
 359
 360         dac_audio_reset(chip);
 361         chip->rate = 8000;
 362         dac_audio_set_rate(chip);
 363
 364         chip->pdata = devptr->dev.platform_data;
 365
 366         chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL);
 367         if (chip->data_buffer == NULL) {
 368                 kfree(chip);
 369                 return -ENOMEM;
 370         }
 371
 372         err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
 373         if (err < 0) {
 374                 snd_sh_dac_free(chip);
 375                 return err;
 376         }
 377
 378         *rchip = chip;
 379
 380         return 0;
 381 }
 382
 383 /* driver .probe  --  constructor */
 384 static int snd_sh_dac_probe(struct platform_device *devptr)
 385 {
 386         struct snd_sh_dac *chip;
 387         struct snd_card *card;
 388         int err;
 389
 390         err = snd_card_new(&devptr->dev, index, id, THIS_MODULE, 0, &card);
 391         if (err < 0) {
 392                         snd_printk(KERN_ERR "cannot allocate the card\n");
 393                         return err;
 394         }
 395
 396         err = snd_sh_dac_create(card, devptr, &chip);
 397         if (err < 0)
 398                 goto probe_error;
 399
 400         err = snd_sh_dac_pcm(chip, 0);
 401         if (err < 0)
 402                 goto probe_error;
 403
 404         strcpy(card->driver, "snd_sh_dac");
 405         strcpy(card->shortname, "SuperH DAC audio driver");
 406         printk(KERN_INFO "%s %s", card->longname, card->shortname);
 407
 408         err = snd_card_register(card);
 409         if (err < 0)
 410                 goto probe_error;
 411
 412         snd_printk(KERN_INFO "ALSA driver for SuperH DAC audio");
 413
 414         platform_set_drvdata(devptr, card);
 415         return 0;
 416
 417 probe_error:
 418         snd_card_free(card);
 419         return err;
 420 }
 421
 422 /*
 423  * "driver" definition
 424  */
 425 static struct platform_driver sh_dac_driver = {
 426         .probe  = snd_sh_dac_probe,
 427         .remove = snd_sh_dac_remove,
 428         .driver = {
 429                 .name = "dac_audio",
 430         },
 431 };
 432
 433 module_platform_driver(sh_dac_driver);