1 /* 2 * atmel-pcm.c -- ALSA PCM interface for the Atmel atmel SoC. 3 * 4 * Copyright (C) 2005 SAN People 5 * Copyright (C) 2008 Atmel 6 * 7 * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com> 8 * 9 * Based on at91-pcm. by: 10 * Frank Mandarino <fmandarino@endrelia.com> 11 * Copyright 2006 Endrelia Technologies Inc. 12 * 13 * Based on pxa2xx-pcm.c by: 14 * 15 * Author: Nicolas Pitre 16 * Created: Nov 30, 2004 17 * Copyright: (C) 2004 MontaVista Software, Inc. 18 * 19 * This program is free software; you can redistribute it and/or modify 20 * it under the terms of the GNU General Public License as published by 21 * the Free Software Foundation; either version 2 of the License, or 22 * (at your option) any later version. 23 * 24 * This program is distributed in the hope that it will be useful, 25 * but WITHOUT ANY WARRANTY; without even the implied warranty of 26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 27 * GNU General Public License for more details. 28 * 29 * You should have received a copy of the GNU General Public License 30 * along with this program; if not, write to the Free Software 31 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 32 */ 33 34 #include <linux/module.h> 35 #include <linux/init.h> 36 #include <linux/platform_device.h> 37 #include <linux/slab.h> 38 #include <linux/dma-mapping.h> 39 #include <linux/atmel_pdc.h> 40 #include <linux/atmel-ssc.h> 41 42 #include <sound/core.h> 43 #include <sound/pcm.h> 44 #include <sound/pcm_params.h> 45 #include <sound/soc.h> 46 47 #include "atmel-pcm.h" 48 49 50 static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, 51 int stream) 52 { 53 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 54 struct snd_dma_buffer *buf = &substream->dma_buffer; 55 size_t size = ATMEL_SSC_DMABUF_SIZE; 56 57 buf->dev.type = SNDRV_DMA_TYPE_DEV; 58 buf->dev.dev = pcm->card->dev; 59 buf->private_data = NULL; 60 buf->area = dma_alloc_coherent(pcm->card->dev, size, 61 &buf->addr, GFP_KERNEL); 62 pr_debug("atmel-pcm: alloc dma buffer: area=%p, addr=%p, size=%zu\n", 63 (void *)buf->area, (void *)(long)buf->addr, size); 64 65 if (!buf->area) 66 return -ENOMEM; 67 68 buf->bytes = size; 69 return 0; 70 } 71 72 static int atmel_pcm_mmap(struct snd_pcm_substream *substream, 73 struct vm_area_struct *vma) 74 { 75 return remap_pfn_range(vma, vma->vm_start, 76 substream->dma_buffer.addr >> PAGE_SHIFT, 77 vma->vm_end - vma->vm_start, vma->vm_page_prot); 78 } 79 80 static int atmel_pcm_new(struct snd_soc_pcm_runtime *rtd) 81 { 82 struct snd_card *card = rtd->card->snd_card; 83 struct snd_pcm *pcm = rtd->pcm; 84 int ret; 85 86 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 87 if (ret) 88 return ret; 89 90 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 91 pr_debug("atmel-pcm: allocating PCM playback DMA buffer\n"); 92 ret = atmel_pcm_preallocate_dma_buffer(pcm, 93 SNDRV_PCM_STREAM_PLAYBACK); 94 if (ret) 95 goto out; 96 } 97 98 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) { 99 pr_debug("atmel-pcm: allocating PCM capture DMA buffer\n"); 100 ret = atmel_pcm_preallocate_dma_buffer(pcm, 101 SNDRV_PCM_STREAM_CAPTURE); 102 if (ret) 103 goto out; 104 } 105 out: 106 return ret; 107 } 108 109 static void atmel_pcm_free(struct snd_pcm *pcm) 110 { 111 struct snd_pcm_substream *substream; 112 struct snd_dma_buffer *buf; 113 int stream; 114 115 for (stream = 0; stream < 2; stream++) { 116 substream = pcm->streams[stream].substream; 117 if (!substream) 118 continue; 119 120 buf = &substream->dma_buffer; 121 if (!buf->area) 122 continue; 123 dma_free_coherent(pcm->card->dev, buf->bytes, 124 buf->area, buf->addr); 125 buf->area = NULL; 126 } 127 } 128 129 /*--------------------------------------------------------------------------*\ 130 * Hardware definition 131 \*--------------------------------------------------------------------------*/ 132 /* TODO: These values were taken from the AT91 platform driver, check 133 * them against real values for AT32 134 */ 135 static const struct snd_pcm_hardware atmel_pcm_hardware = { 136 .info = SNDRV_PCM_INFO_MMAP | 137 SNDRV_PCM_INFO_MMAP_VALID | 138 SNDRV_PCM_INFO_INTERLEAVED | 139 SNDRV_PCM_INFO_PAUSE, 140 .period_bytes_min = 32, 141 .period_bytes_max = 8192, 142 .periods_min = 2, 143 .periods_max = 1024, 144 .buffer_bytes_max = ATMEL_SSC_DMABUF_SIZE, 145 }; 146 147 148 /*--------------------------------------------------------------------------*\ 149 * Data types 150 \*--------------------------------------------------------------------------*/ 151 struct atmel_runtime_data { 152 struct atmel_pcm_dma_params *params; 153 dma_addr_t dma_buffer; /* physical address of dma buffer */ 154 dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */ 155 size_t period_size; 156 157 dma_addr_t period_ptr; /* physical address of next period */ 158 }; 159 160 /*--------------------------------------------------------------------------*\ 161 * ISR 162 \*--------------------------------------------------------------------------*/ 163 static void atmel_pcm_dma_irq(u32 ssc_sr, 164 struct snd_pcm_substream *substream) 165 { 166 struct atmel_runtime_data *prtd = substream->runtime->private_data; 167 struct atmel_pcm_dma_params *params = prtd->params; 168 static int count; 169 170 count++; 171 172 if (ssc_sr & params->mask->ssc_endbuf) { 173 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n", 174 substream->stream == SNDRV_PCM_STREAM_PLAYBACK 175 ? "underrun" : "overrun", 176 params->name, ssc_sr, count); 177 178 /* re-start the PDC */ 179 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 180 params->mask->pdc_disable); 181 prtd->period_ptr += prtd->period_size; 182 if (prtd->period_ptr >= prtd->dma_buffer_end) 183 prtd->period_ptr = prtd->dma_buffer; 184 185 ssc_writex(params->ssc->regs, params->pdc->xpr, 186 prtd->period_ptr); 187 ssc_writex(params->ssc->regs, params->pdc->xcr, 188 prtd->period_size / params->pdc_xfer_size); 189 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 190 params->mask->pdc_enable); 191 } 192 193 if (ssc_sr & params->mask->ssc_endx) { 194 /* Load the PDC next pointer and counter registers */ 195 prtd->period_ptr += prtd->period_size; 196 if (prtd->period_ptr >= prtd->dma_buffer_end) 197 prtd->period_ptr = prtd->dma_buffer; 198 199 ssc_writex(params->ssc->regs, params->pdc->xnpr, 200 prtd->period_ptr); 201 ssc_writex(params->ssc->regs, params->pdc->xncr, 202 prtd->period_size / params->pdc_xfer_size); 203 } 204 205 snd_pcm_period_elapsed(substream); 206 } 207 208 209 /*--------------------------------------------------------------------------*\ 210 * PCM operations 211 \*--------------------------------------------------------------------------*/ 212 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream, 213 struct snd_pcm_hw_params *params) 214 { 215 struct snd_pcm_runtime *runtime = substream->runtime; 216 struct atmel_runtime_data *prtd = runtime->private_data; 217 struct snd_soc_pcm_runtime *rtd = substream->private_data; 218 219 /* this may get called several times by oss emulation 220 * with different params */ 221 222 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 223 runtime->dma_bytes = params_buffer_bytes(params); 224 225 prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 226 prtd->params->dma_intr_handler = atmel_pcm_dma_irq; 227 228 prtd->dma_buffer = runtime->dma_addr; 229 prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes; 230 prtd->period_size = params_period_bytes(params); 231 232 pr_debug("atmel-pcm: " 233 "hw_params: DMA for %s initialized " 234 "(dma_bytes=%zu, period_size=%zu)\n", 235 prtd->params->name, 236 runtime->dma_bytes, 237 prtd->period_size); 238 return 0; 239 } 240 241 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream) 242 { 243 struct atmel_runtime_data *prtd = substream->runtime->private_data; 244 struct atmel_pcm_dma_params *params = prtd->params; 245 246 if (params != NULL) { 247 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 248 params->mask->pdc_disable); 249 prtd->params->dma_intr_handler = NULL; 250 } 251 252 return 0; 253 } 254 255 static int atmel_pcm_prepare(struct snd_pcm_substream *substream) 256 { 257 struct atmel_runtime_data *prtd = substream->runtime->private_data; 258 struct atmel_pcm_dma_params *params = prtd->params; 259 260 ssc_writex(params->ssc->regs, SSC_IDR, 261 params->mask->ssc_endx | params->mask->ssc_endbuf); 262 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 263 params->mask->pdc_disable); 264 return 0; 265 } 266 267 static int atmel_pcm_trigger(struct snd_pcm_substream *substream, 268 int cmd) 269 { 270 struct snd_pcm_runtime *rtd = substream->runtime; 271 struct atmel_runtime_data *prtd = rtd->private_data; 272 struct atmel_pcm_dma_params *params = prtd->params; 273 int ret = 0; 274 275 pr_debug("atmel-pcm:buffer_size = %ld," 276 "dma_area = %p, dma_bytes = %zu\n", 277 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes); 278 279 switch (cmd) { 280 case SNDRV_PCM_TRIGGER_START: 281 prtd->period_ptr = prtd->dma_buffer; 282 283 ssc_writex(params->ssc->regs, params->pdc->xpr, 284 prtd->period_ptr); 285 ssc_writex(params->ssc->regs, params->pdc->xcr, 286 prtd->period_size / params->pdc_xfer_size); 287 288 prtd->period_ptr += prtd->period_size; 289 ssc_writex(params->ssc->regs, params->pdc->xnpr, 290 prtd->period_ptr); 291 ssc_writex(params->ssc->regs, params->pdc->xncr, 292 prtd->period_size / params->pdc_xfer_size); 293 294 pr_debug("atmel-pcm: trigger: " 295 "period_ptr=%lx, xpr=%u, " 296 "xcr=%u, xnpr=%u, xncr=%u\n", 297 (unsigned long)prtd->period_ptr, 298 ssc_readx(params->ssc->regs, params->pdc->xpr), 299 ssc_readx(params->ssc->regs, params->pdc->xcr), 300 ssc_readx(params->ssc->regs, params->pdc->xnpr), 301 ssc_readx(params->ssc->regs, params->pdc->xncr)); 302 303 ssc_writex(params->ssc->regs, SSC_IER, 304 params->mask->ssc_endx | params->mask->ssc_endbuf); 305 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 306 params->mask->pdc_enable); 307 308 pr_debug("sr=%u imr=%u\n", 309 ssc_readx(params->ssc->regs, SSC_SR), 310 ssc_readx(params->ssc->regs, SSC_IER)); 311 break; /* SNDRV_PCM_TRIGGER_START */ 312 313 case SNDRV_PCM_TRIGGER_STOP: 314 case SNDRV_PCM_TRIGGER_SUSPEND: 315 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 316 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 317 params->mask->pdc_disable); 318 break; 319 320 case SNDRV_PCM_TRIGGER_RESUME: 321 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 322 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 323 params->mask->pdc_enable); 324 break; 325 326 default: 327 ret = -EINVAL; 328 } 329 330 return ret; 331 } 332 333 static snd_pcm_uframes_t atmel_pcm_pointer( 334 struct snd_pcm_substream *substream) 335 { 336 struct snd_pcm_runtime *runtime = substream->runtime; 337 struct atmel_runtime_data *prtd = runtime->private_data; 338 struct atmel_pcm_dma_params *params = prtd->params; 339 dma_addr_t ptr; 340 snd_pcm_uframes_t x; 341 342 ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr); 343 x = bytes_to_frames(runtime, ptr - prtd->dma_buffer); 344 345 if (x == runtime->buffer_size) 346 x = 0; 347 348 return x; 349 } 350 351 static int atmel_pcm_open(struct snd_pcm_substream *substream) 352 { 353 struct snd_pcm_runtime *runtime = substream->runtime; 354 struct atmel_runtime_data *prtd; 355 int ret = 0; 356 357 snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware); 358 359 /* ensure that buffer size is a multiple of period size */ 360 ret = snd_pcm_hw_constraint_integer(runtime, 361 SNDRV_PCM_HW_PARAM_PERIODS); 362 if (ret < 0) 363 goto out; 364 365 prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL); 366 if (prtd == NULL) { 367 ret = -ENOMEM; 368 goto out; 369 } 370 runtime->private_data = prtd; 371 372 out: 373 return ret; 374 } 375 376 static int atmel_pcm_close(struct snd_pcm_substream *substream) 377 { 378 struct atmel_runtime_data *prtd = substream->runtime->private_data; 379 380 kfree(prtd); 381 return 0; 382 } 383 384 static struct snd_pcm_ops atmel_pcm_ops = { 385 .open = atmel_pcm_open, 386 .close = atmel_pcm_close, 387 .ioctl = snd_pcm_lib_ioctl, 388 .hw_params = atmel_pcm_hw_params, 389 .hw_free = atmel_pcm_hw_free, 390 .prepare = atmel_pcm_prepare, 391 .trigger = atmel_pcm_trigger, 392 .pointer = atmel_pcm_pointer, 393 .mmap = atmel_pcm_mmap, 394 }; 395 396 static struct snd_soc_platform_driver atmel_soc_platform = { 397 .ops = &atmel_pcm_ops, 398 .pcm_new = atmel_pcm_new, 399 .pcm_free = atmel_pcm_free, 400 }; 401 402 int atmel_pcm_pdc_platform_register(struct device *dev) 403 { 404 return snd_soc_register_platform(dev, &atmel_soc_platform); 405 } 406 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register); 407 408 void atmel_pcm_pdc_platform_unregister(struct device *dev) 409 { 410 snd_soc_unregister_platform(dev); 411 } 412 EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister); 413 414 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>"); 415 MODULE_DESCRIPTION("Atmel PCM module"); 416 MODULE_LICENSE("GPL"); 417