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