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 /*--------------------------------------------------------------------------*\ 51 * Hardware definition 52 \*--------------------------------------------------------------------------*/ 53 /* TODO: These values were taken from the AT91 platform driver, check 54 * them against real values for AT32 55 */ 56 static const struct snd_pcm_hardware atmel_pcm_hardware = { 57 .info = SNDRV_PCM_INFO_MMAP | 58 SNDRV_PCM_INFO_MMAP_VALID | 59 SNDRV_PCM_INFO_INTERLEAVED | 60 SNDRV_PCM_INFO_PAUSE, 61 .formats = SNDRV_PCM_FMTBIT_S16_LE, 62 .period_bytes_min = 32, 63 .period_bytes_max = 8192, 64 .periods_min = 2, 65 .periods_max = 1024, 66 .buffer_bytes_max = ATMEL_SSC_DMABUF_SIZE, 67 }; 68 69 70 /*--------------------------------------------------------------------------*\ 71 * Data types 72 \*--------------------------------------------------------------------------*/ 73 struct atmel_runtime_data { 74 struct atmel_pcm_dma_params *params; 75 dma_addr_t dma_buffer; /* physical address of dma buffer */ 76 dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */ 77 size_t period_size; 78 79 dma_addr_t period_ptr; /* physical address of next period */ 80 81 /* PDC register save */ 82 u32 pdc_xpr_save; 83 u32 pdc_xcr_save; 84 u32 pdc_xnpr_save; 85 u32 pdc_xncr_save; 86 }; 87 88 /*--------------------------------------------------------------------------*\ 89 * ISR 90 \*--------------------------------------------------------------------------*/ 91 static void atmel_pcm_dma_irq(u32 ssc_sr, 92 struct snd_pcm_substream *substream) 93 { 94 struct atmel_runtime_data *prtd = substream->runtime->private_data; 95 struct atmel_pcm_dma_params *params = prtd->params; 96 static int count; 97 98 count++; 99 100 if (ssc_sr & params->mask->ssc_endbuf) { 101 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n", 102 substream->stream == SNDRV_PCM_STREAM_PLAYBACK 103 ? "underrun" : "overrun", 104 params->name, ssc_sr, count); 105 106 /* re-start the PDC */ 107 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 108 params->mask->pdc_disable); 109 prtd->period_ptr += prtd->period_size; 110 if (prtd->period_ptr >= prtd->dma_buffer_end) 111 prtd->period_ptr = prtd->dma_buffer; 112 113 ssc_writex(params->ssc->regs, params->pdc->xpr, 114 prtd->period_ptr); 115 ssc_writex(params->ssc->regs, params->pdc->xcr, 116 prtd->period_size / params->pdc_xfer_size); 117 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 118 params->mask->pdc_enable); 119 } 120 121 if (ssc_sr & params->mask->ssc_endx) { 122 /* Load the PDC next pointer and counter registers */ 123 prtd->period_ptr += prtd->period_size; 124 if (prtd->period_ptr >= prtd->dma_buffer_end) 125 prtd->period_ptr = prtd->dma_buffer; 126 127 ssc_writex(params->ssc->regs, params->pdc->xnpr, 128 prtd->period_ptr); 129 ssc_writex(params->ssc->regs, params->pdc->xncr, 130 prtd->period_size / params->pdc_xfer_size); 131 } 132 133 snd_pcm_period_elapsed(substream); 134 } 135 136 137 /*--------------------------------------------------------------------------*\ 138 * PCM operations 139 \*--------------------------------------------------------------------------*/ 140 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream, 141 struct snd_pcm_hw_params *params) 142 { 143 struct snd_pcm_runtime *runtime = substream->runtime; 144 struct atmel_runtime_data *prtd = runtime->private_data; 145 struct snd_soc_pcm_runtime *rtd = substream->private_data; 146 147 /* this may get called several times by oss emulation 148 * with different params */ 149 150 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 151 runtime->dma_bytes = params_buffer_bytes(params); 152 153 prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 154 prtd->params->dma_intr_handler = atmel_pcm_dma_irq; 155 156 prtd->dma_buffer = runtime->dma_addr; 157 prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes; 158 prtd->period_size = params_period_bytes(params); 159 160 pr_debug("atmel-pcm: " 161 "hw_params: DMA for %s initialized " 162 "(dma_bytes=%zu, period_size=%zu)\n", 163 prtd->params->name, 164 runtime->dma_bytes, 165 prtd->period_size); 166 return 0; 167 } 168 169 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream) 170 { 171 struct atmel_runtime_data *prtd = substream->runtime->private_data; 172 struct atmel_pcm_dma_params *params = prtd->params; 173 174 if (params != NULL) { 175 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 176 params->mask->pdc_disable); 177 prtd->params->dma_intr_handler = NULL; 178 } 179 180 return 0; 181 } 182 183 static int atmel_pcm_prepare(struct snd_pcm_substream *substream) 184 { 185 struct atmel_runtime_data *prtd = substream->runtime->private_data; 186 struct atmel_pcm_dma_params *params = prtd->params; 187 188 ssc_writex(params->ssc->regs, SSC_IDR, 189 params->mask->ssc_endx | params->mask->ssc_endbuf); 190 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 191 params->mask->pdc_disable); 192 return 0; 193 } 194 195 static int atmel_pcm_trigger(struct snd_pcm_substream *substream, 196 int cmd) 197 { 198 struct snd_pcm_runtime *rtd = substream->runtime; 199 struct atmel_runtime_data *prtd = rtd->private_data; 200 struct atmel_pcm_dma_params *params = prtd->params; 201 int ret = 0; 202 203 pr_debug("atmel-pcm:buffer_size = %ld," 204 "dma_area = %p, dma_bytes = %zu\n", 205 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes); 206 207 switch (cmd) { 208 case SNDRV_PCM_TRIGGER_START: 209 prtd->period_ptr = prtd->dma_buffer; 210 211 ssc_writex(params->ssc->regs, params->pdc->xpr, 212 prtd->period_ptr); 213 ssc_writex(params->ssc->regs, params->pdc->xcr, 214 prtd->period_size / params->pdc_xfer_size); 215 216 prtd->period_ptr += prtd->period_size; 217 ssc_writex(params->ssc->regs, params->pdc->xnpr, 218 prtd->period_ptr); 219 ssc_writex(params->ssc->regs, params->pdc->xncr, 220 prtd->period_size / params->pdc_xfer_size); 221 222 pr_debug("atmel-pcm: trigger: " 223 "period_ptr=%lx, xpr=%u, " 224 "xcr=%u, xnpr=%u, xncr=%u\n", 225 (unsigned long)prtd->period_ptr, 226 ssc_readx(params->ssc->regs, params->pdc->xpr), 227 ssc_readx(params->ssc->regs, params->pdc->xcr), 228 ssc_readx(params->ssc->regs, params->pdc->xnpr), 229 ssc_readx(params->ssc->regs, params->pdc->xncr)); 230 231 ssc_writex(params->ssc->regs, SSC_IER, 232 params->mask->ssc_endx | params->mask->ssc_endbuf); 233 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 234 params->mask->pdc_enable); 235 236 pr_debug("sr=%u imr=%u\n", 237 ssc_readx(params->ssc->regs, SSC_SR), 238 ssc_readx(params->ssc->regs, SSC_IER)); 239 break; /* SNDRV_PCM_TRIGGER_START */ 240 241 case SNDRV_PCM_TRIGGER_STOP: 242 case SNDRV_PCM_TRIGGER_SUSPEND: 243 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 244 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 245 params->mask->pdc_disable); 246 break; 247 248 case SNDRV_PCM_TRIGGER_RESUME: 249 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 250 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 251 params->mask->pdc_enable); 252 break; 253 254 default: 255 ret = -EINVAL; 256 } 257 258 return ret; 259 } 260 261 static snd_pcm_uframes_t atmel_pcm_pointer( 262 struct snd_pcm_substream *substream) 263 { 264 struct snd_pcm_runtime *runtime = substream->runtime; 265 struct atmel_runtime_data *prtd = runtime->private_data; 266 struct atmel_pcm_dma_params *params = prtd->params; 267 dma_addr_t ptr; 268 snd_pcm_uframes_t x; 269 270 ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr); 271 x = bytes_to_frames(runtime, ptr - prtd->dma_buffer); 272 273 if (x == runtime->buffer_size) 274 x = 0; 275 276 return x; 277 } 278 279 static int atmel_pcm_open(struct snd_pcm_substream *substream) 280 { 281 struct snd_pcm_runtime *runtime = substream->runtime; 282 struct atmel_runtime_data *prtd; 283 int ret = 0; 284 285 snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware); 286 287 /* ensure that buffer size is a multiple of period size */ 288 ret = snd_pcm_hw_constraint_integer(runtime, 289 SNDRV_PCM_HW_PARAM_PERIODS); 290 if (ret < 0) 291 goto out; 292 293 prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL); 294 if (prtd == NULL) { 295 ret = -ENOMEM; 296 goto out; 297 } 298 runtime->private_data = prtd; 299 300 out: 301 return ret; 302 } 303 304 static int atmel_pcm_close(struct snd_pcm_substream *substream) 305 { 306 struct atmel_runtime_data *prtd = substream->runtime->private_data; 307 308 kfree(prtd); 309 return 0; 310 } 311 312 static struct snd_pcm_ops atmel_pcm_ops = { 313 .open = atmel_pcm_open, 314 .close = atmel_pcm_close, 315 .ioctl = snd_pcm_lib_ioctl, 316 .hw_params = atmel_pcm_hw_params, 317 .hw_free = atmel_pcm_hw_free, 318 .prepare = atmel_pcm_prepare, 319 .trigger = atmel_pcm_trigger, 320 .pointer = atmel_pcm_pointer, 321 .mmap = atmel_pcm_mmap, 322 }; 323 324 325 /*--------------------------------------------------------------------------*\ 326 * ASoC platform driver 327 \*--------------------------------------------------------------------------*/ 328 #ifdef CONFIG_PM 329 static int atmel_pcm_suspend(struct snd_soc_dai *dai) 330 { 331 struct snd_pcm_runtime *runtime = dai->runtime; 332 struct atmel_runtime_data *prtd; 333 struct atmel_pcm_dma_params *params; 334 335 if (!runtime) 336 return 0; 337 338 prtd = runtime->private_data; 339 params = prtd->params; 340 341 /* disable the PDC and save the PDC registers */ 342 343 ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable); 344 345 prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr); 346 prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr); 347 prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr); 348 prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr); 349 350 return 0; 351 } 352 353 static int atmel_pcm_resume(struct snd_soc_dai *dai) 354 { 355 struct snd_pcm_runtime *runtime = dai->runtime; 356 struct atmel_runtime_data *prtd; 357 struct atmel_pcm_dma_params *params; 358 359 if (!runtime) 360 return 0; 361 362 prtd = runtime->private_data; 363 params = prtd->params; 364 365 /* restore the PDC registers and enable the PDC */ 366 ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save); 367 ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save); 368 ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save); 369 ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save); 370 371 ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable); 372 return 0; 373 } 374 #else 375 #define atmel_pcm_suspend NULL 376 #define atmel_pcm_resume NULL 377 #endif 378 379 static struct snd_soc_platform_driver atmel_soc_platform = { 380 .ops = &atmel_pcm_ops, 381 .pcm_new = atmel_pcm_new, 382 .pcm_free = atmel_pcm_free, 383 .suspend = atmel_pcm_suspend, 384 .resume = atmel_pcm_resume, 385 }; 386 387 int atmel_pcm_pdc_platform_register(struct device *dev) 388 { 389 return snd_soc_register_platform(dev, &atmel_soc_platform); 390 } 391 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register); 392 393 void atmel_pcm_pdc_platform_unregister(struct device *dev) 394 { 395 snd_soc_unregister_platform(dev); 396 } 397 EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister); 398 399 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>"); 400 MODULE_DESCRIPTION("Atmel PCM module"); 401 MODULE_LICENSE("GPL"); 402