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