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_prepare(struct snd_pcm_substream *substream) 129 { 130 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); 131 struct snd_pcm_runtime *runtime = chip->substream->runtime; 132 133 chip->buffer_size = runtime->buffer_size; 134 memset(chip->data_buffer, 0, chip->pdata->buffer_size); 135 136 return 0; 137 } 138 139 static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd) 140 { 141 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); 142 143 switch (cmd) { 144 case SNDRV_PCM_TRIGGER_START: 145 dac_audio_start_timer(chip); 146 break; 147 case SNDRV_PCM_TRIGGER_STOP: 148 chip->buffer_begin = chip->buffer_end = chip->data_buffer; 149 chip->processed = 0; 150 chip->empty = 1; 151 dac_audio_stop_timer(chip); 152 break; 153 default: 154 return -EINVAL; 155 } 156 157 return 0; 158 } 159 160 static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream, 161 int channel, unsigned long pos, 162 void __user *src, unsigned long count) 163 { 164 /* channel is not used (interleaved data) */ 165 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); 166 struct snd_pcm_runtime *runtime = substream->runtime; 167 168 if (copy_from_user_toio(chip->data_buffer + pos, src, count)) 169 return -EFAULT; 170 chip->buffer_end = chip->data_buffer + pos + count; 171 172 if (chip->empty) { 173 chip->empty = 0; 174 dac_audio_start_timer(chip); 175 } 176 177 return 0; 178 } 179 180 static int snd_sh_dac_pcm_copy_kernel(struct snd_pcm_substream *substream, 181 int channel, unsigned long pos, 182 void *src, unsigned long count) 183 { 184 /* channel is not used (interleaved data) */ 185 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); 186 struct snd_pcm_runtime *runtime = substream->runtime; 187 188 memcpy_toio(chip->data_buffer + pos, src, count); 189 chip->buffer_end = chip->data_buffer + pos + count; 190 191 if (chip->empty) { 192 chip->empty = 0; 193 dac_audio_start_timer(chip); 194 } 195 196 return 0; 197 } 198 199 static int snd_sh_dac_pcm_silence(struct snd_pcm_substream *substream, 200 int channel, unsigned long pos, 201 unsigned long count) 202 { 203 /* channel is not used (interleaved data) */ 204 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); 205 struct snd_pcm_runtime *runtime = substream->runtime; 206 207 memset_io(chip->data_buffer + pos, 0, count); 208 chip->buffer_end = chip->data_buffer + pos + count; 209 210 if (chip->empty) { 211 chip->empty = 0; 212 dac_audio_start_timer(chip); 213 } 214 215 return 0; 216 } 217 218 static 219 snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream) 220 { 221 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); 222 int pointer = chip->buffer_begin - chip->data_buffer; 223 224 return pointer; 225 } 226 227 /* pcm ops */ 228 static const struct snd_pcm_ops snd_sh_dac_pcm_ops = { 229 .open = snd_sh_dac_pcm_open, 230 .close = snd_sh_dac_pcm_close, 231 .prepare = snd_sh_dac_pcm_prepare, 232 .trigger = snd_sh_dac_pcm_trigger, 233 .pointer = snd_sh_dac_pcm_pointer, 234 .copy_user = snd_sh_dac_pcm_copy, 235 .copy_kernel = snd_sh_dac_pcm_copy_kernel, 236 .fill_silence = snd_sh_dac_pcm_silence, 237 .mmap = snd_pcm_lib_mmap_iomem, 238 }; 239 240 static int snd_sh_dac_pcm(struct snd_sh_dac *chip, int device) 241 { 242 int err; 243 struct snd_pcm *pcm; 244 245 /* device should be always 0 for us */ 246 err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm); 247 if (err < 0) 248 return err; 249 250 pcm->private_data = chip; 251 strcpy(pcm->name, "SH_DAC PCM"); 252 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops); 253 254 /* buffer size=48K */ 255 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, 256 NULL, 48 * 1024, 48 * 1024); 257 258 return 0; 259 } 260 /* END OF PCM INTERFACE */ 261 262 263 /* driver .remove -- destructor */ 264 static int snd_sh_dac_remove(struct platform_device *devptr) 265 { 266 snd_card_free(platform_get_drvdata(devptr)); 267 return 0; 268 } 269 270 /* free -- it has been defined by create */ 271 static int snd_sh_dac_free(struct snd_sh_dac *chip) 272 { 273 /* release the data */ 274 kfree(chip->data_buffer); 275 kfree(chip); 276 277 return 0; 278 } 279 280 static int snd_sh_dac_dev_free(struct snd_device *device) 281 { 282 struct snd_sh_dac *chip = device->device_data; 283 284 return snd_sh_dac_free(chip); 285 } 286 287 static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle) 288 { 289 struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac, 290 hrtimer); 291 struct snd_pcm_runtime *runtime = chip->substream->runtime; 292 ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size); 293 294 if (!chip->empty) { 295 sh_dac_output(*chip->buffer_begin, chip->pdata->channel); 296 chip->buffer_begin++; 297 298 chip->processed++; 299 if (chip->processed >= b_ps) { 300 chip->processed -= b_ps; 301 snd_pcm_period_elapsed(chip->substream); 302 } 303 304 if (chip->buffer_begin == (chip->data_buffer + 305 chip->buffer_size - 1)) 306 chip->buffer_begin = chip->data_buffer; 307 308 if (chip->buffer_begin == chip->buffer_end) 309 chip->empty = 1; 310 311 } 312 313 if (!chip->empty) 314 hrtimer_start(&chip->hrtimer, chip->wakeups_per_second, 315 HRTIMER_MODE_REL); 316 317 return HRTIMER_NORESTART; 318 } 319 320 /* create -- chip-specific constructor for the cards components */ 321 static int snd_sh_dac_create(struct snd_card *card, 322 struct platform_device *devptr, 323 struct snd_sh_dac **rchip) 324 { 325 struct snd_sh_dac *chip; 326 int err; 327 328 static struct snd_device_ops ops = { 329 .dev_free = snd_sh_dac_dev_free, 330 }; 331 332 *rchip = NULL; 333 334 chip = kzalloc(sizeof(*chip), GFP_KERNEL); 335 if (chip == NULL) 336 return -ENOMEM; 337 338 chip->card = card; 339 340 hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 341 chip->hrtimer.function = sh_dac_audio_timer; 342 343 dac_audio_reset(chip); 344 chip->rate = 8000; 345 dac_audio_set_rate(chip); 346 347 chip->pdata = devptr->dev.platform_data; 348 349 chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL); 350 if (chip->data_buffer == NULL) { 351 kfree(chip); 352 return -ENOMEM; 353 } 354 355 err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops); 356 if (err < 0) { 357 snd_sh_dac_free(chip); 358 return err; 359 } 360 361 *rchip = chip; 362 363 return 0; 364 } 365 366 /* driver .probe -- constructor */ 367 static int snd_sh_dac_probe(struct platform_device *devptr) 368 { 369 struct snd_sh_dac *chip; 370 struct snd_card *card; 371 int err; 372 373 err = snd_card_new(&devptr->dev, index, id, THIS_MODULE, 0, &card); 374 if (err < 0) { 375 snd_printk(KERN_ERR "cannot allocate the card\n"); 376 return err; 377 } 378 379 err = snd_sh_dac_create(card, devptr, &chip); 380 if (err < 0) 381 goto probe_error; 382 383 err = snd_sh_dac_pcm(chip, 0); 384 if (err < 0) 385 goto probe_error; 386 387 strcpy(card->driver, "snd_sh_dac"); 388 strcpy(card->shortname, "SuperH DAC audio driver"); 389 printk(KERN_INFO "%s %s", card->longname, card->shortname); 390 391 err = snd_card_register(card); 392 if (err < 0) 393 goto probe_error; 394 395 snd_printk(KERN_INFO "ALSA driver for SuperH DAC audio"); 396 397 platform_set_drvdata(devptr, card); 398 return 0; 399 400 probe_error: 401 snd_card_free(card); 402 return err; 403 } 404 405 /* 406 * "driver" definition 407 */ 408 static struct platform_driver sh_dac_driver = { 409 .probe = snd_sh_dac_probe, 410 .remove = snd_sh_dac_remove, 411 .driver = { 412 .name = "dac_audio", 413 }, 414 }; 415 416 module_platform_driver(sh_dac_driver); 417