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 snd_dma_continuous_data(GFP_KERNEL), 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); 434