1 /* 2 * linux/sound/arm/pxa2xx-pcm.c -- ALSA PCM interface for the Intel PXA2xx chip 3 * 4 * Author: Nicolas Pitre 5 * Created: Nov 30, 2004 6 * Copyright: (C) 2004 MontaVista Software, Inc. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/platform_device.h> 16 #include <linux/slab.h> 17 #include <linux/dma-mapping.h> 18 19 #include <sound/core.h> 20 #include <sound/pcm.h> 21 #include <sound/pcm_params.h> 22 #include <sound/soc.h> 23 24 #include <asm/dma.h> 25 #include <asm/hardware.h> 26 #include <asm/arch/pxa-regs.h> 27 #include <asm/arch/audio.h> 28 29 #include "pxa2xx-pcm.h" 30 31 static const struct snd_pcm_hardware pxa2xx_pcm_hardware = { 32 .info = SNDRV_PCM_INFO_MMAP | 33 SNDRV_PCM_INFO_MMAP_VALID | 34 SNDRV_PCM_INFO_INTERLEAVED | 35 SNDRV_PCM_INFO_PAUSE | 36 SNDRV_PCM_INFO_RESUME, 37 .formats = SNDRV_PCM_FMTBIT_S16_LE | 38 SNDRV_PCM_FMTBIT_S24_LE | 39 SNDRV_PCM_FMTBIT_S32_LE, 40 .period_bytes_min = 32, 41 .period_bytes_max = 8192 - 32, 42 .periods_min = 1, 43 .periods_max = PAGE_SIZE/sizeof(pxa_dma_desc), 44 .buffer_bytes_max = 128 * 1024, 45 .fifo_size = 32, 46 }; 47 48 struct pxa2xx_runtime_data { 49 int dma_ch; 50 struct pxa2xx_pcm_dma_params *params; 51 pxa_dma_desc *dma_desc_array; 52 dma_addr_t dma_desc_array_phys; 53 }; 54 55 static void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id) 56 { 57 struct snd_pcm_substream *substream = dev_id; 58 struct pxa2xx_runtime_data *prtd = substream->runtime->private_data; 59 int dcsr; 60 61 dcsr = DCSR(dma_ch); 62 DCSR(dma_ch) = dcsr & ~DCSR_STOPIRQEN; 63 64 if (dcsr & DCSR_ENDINTR) { 65 snd_pcm_period_elapsed(substream); 66 } else { 67 printk(KERN_ERR "%s: DMA error on channel %d (DCSR=%#x)\n", 68 prtd->params->name, dma_ch, dcsr); 69 } 70 } 71 72 static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream, 73 struct snd_pcm_hw_params *params) 74 { 75 struct snd_pcm_runtime *runtime = substream->runtime; 76 struct pxa2xx_runtime_data *prtd = runtime->private_data; 77 struct snd_soc_pcm_runtime *rtd = substream->private_data; 78 struct pxa2xx_pcm_dma_params *dma = rtd->dai->cpu_dai->dma_data; 79 size_t totsize = params_buffer_bytes(params); 80 size_t period = params_period_bytes(params); 81 pxa_dma_desc *dma_desc; 82 dma_addr_t dma_buff_phys, next_desc_phys; 83 int ret; 84 85 /* return if this is a bufferless transfer e.g. 86 * codec <--> BT codec or GSM modem -- lg FIXME */ 87 if (!dma) 88 return 0; 89 90 /* this may get called several times by oss emulation 91 * with different params */ 92 if (prtd->params == NULL) { 93 prtd->params = dma; 94 ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW, 95 pxa2xx_pcm_dma_irq, substream); 96 if (ret < 0) 97 return ret; 98 prtd->dma_ch = ret; 99 } else if (prtd->params != dma) { 100 pxa_free_dma(prtd->dma_ch); 101 prtd->params = dma; 102 ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW, 103 pxa2xx_pcm_dma_irq, substream); 104 if (ret < 0) 105 return ret; 106 prtd->dma_ch = ret; 107 } 108 109 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 110 runtime->dma_bytes = totsize; 111 112 dma_desc = prtd->dma_desc_array; 113 next_desc_phys = prtd->dma_desc_array_phys; 114 dma_buff_phys = runtime->dma_addr; 115 do { 116 next_desc_phys += sizeof(pxa_dma_desc); 117 dma_desc->ddadr = next_desc_phys; 118 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { 119 dma_desc->dsadr = dma_buff_phys; 120 dma_desc->dtadr = prtd->params->dev_addr; 121 } else { 122 dma_desc->dsadr = prtd->params->dev_addr; 123 dma_desc->dtadr = dma_buff_phys; 124 } 125 if (period > totsize) 126 period = totsize; 127 dma_desc->dcmd = prtd->params->dcmd | period | DCMD_ENDIRQEN; 128 dma_desc++; 129 dma_buff_phys += period; 130 } while (totsize -= period); 131 dma_desc[-1].ddadr = prtd->dma_desc_array_phys; 132 133 return 0; 134 } 135 136 static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream) 137 { 138 struct pxa2xx_runtime_data *prtd = substream->runtime->private_data; 139 140 if (prtd && prtd->params) 141 *prtd->params->drcmr = 0; 142 143 if (prtd->dma_ch) { 144 snd_pcm_set_runtime_buffer(substream, NULL); 145 pxa_free_dma(prtd->dma_ch); 146 prtd->dma_ch = 0; 147 } 148 149 return 0; 150 } 151 152 static int pxa2xx_pcm_prepare(struct snd_pcm_substream *substream) 153 { 154 struct pxa2xx_runtime_data *prtd = substream->runtime->private_data; 155 156 DCSR(prtd->dma_ch) &= ~DCSR_RUN; 157 DCSR(prtd->dma_ch) = 0; 158 DCMD(prtd->dma_ch) = 0; 159 *prtd->params->drcmr = prtd->dma_ch | DRCMR_MAPVLD; 160 161 return 0; 162 } 163 164 static int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd) 165 { 166 struct pxa2xx_runtime_data *prtd = substream->runtime->private_data; 167 int ret = 0; 168 169 switch (cmd) { 170 case SNDRV_PCM_TRIGGER_START: 171 DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys; 172 DCSR(prtd->dma_ch) = DCSR_RUN; 173 break; 174 175 case SNDRV_PCM_TRIGGER_STOP: 176 case SNDRV_PCM_TRIGGER_SUSPEND: 177 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 178 DCSR(prtd->dma_ch) &= ~DCSR_RUN; 179 break; 180 181 case SNDRV_PCM_TRIGGER_RESUME: 182 DCSR(prtd->dma_ch) |= DCSR_RUN; 183 break; 184 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 185 DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys; 186 DCSR(prtd->dma_ch) |= DCSR_RUN; 187 break; 188 189 default: 190 ret = -EINVAL; 191 } 192 193 return ret; 194 } 195 196 static snd_pcm_uframes_t 197 pxa2xx_pcm_pointer(struct snd_pcm_substream *substream) 198 { 199 struct snd_pcm_runtime *runtime = substream->runtime; 200 struct pxa2xx_runtime_data *prtd = runtime->private_data; 201 202 dma_addr_t ptr = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ? 203 DSADR(prtd->dma_ch) : DTADR(prtd->dma_ch); 204 snd_pcm_uframes_t x = bytes_to_frames(runtime, ptr - runtime->dma_addr); 205 206 if (x == runtime->buffer_size) 207 x = 0; 208 return x; 209 } 210 211 static int pxa2xx_pcm_open(struct snd_pcm_substream *substream) 212 { 213 struct snd_pcm_runtime *runtime = substream->runtime; 214 struct pxa2xx_runtime_data *prtd; 215 int ret; 216 217 snd_soc_set_runtime_hwparams(substream, &pxa2xx_pcm_hardware); 218 219 /* 220 * For mysterious reasons (and despite what the manual says) 221 * playback samples are lost if the DMA count is not a multiple 222 * of the DMA burst size. Let's add a rule to enforce that. 223 */ 224 ret = snd_pcm_hw_constraint_step(runtime, 0, 225 SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 32); 226 if (ret) 227 goto out; 228 229 ret = snd_pcm_hw_constraint_step(runtime, 0, 230 SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 32); 231 if (ret) 232 goto out; 233 234 ret = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS); 235 if (ret < 0) 236 goto out; 237 238 prtd = kzalloc(sizeof(struct pxa2xx_runtime_data), GFP_KERNEL); 239 if (prtd == NULL) { 240 ret = -ENOMEM; 241 goto out; 242 } 243 244 prtd->dma_desc_array = 245 dma_alloc_writecombine(substream->pcm->card->dev, PAGE_SIZE, 246 &prtd->dma_desc_array_phys, GFP_KERNEL); 247 if (!prtd->dma_desc_array) { 248 ret = -ENOMEM; 249 goto err1; 250 } 251 252 runtime->private_data = prtd; 253 return 0; 254 255 err1: 256 kfree(prtd); 257 out: 258 return ret; 259 } 260 261 static int pxa2xx_pcm_close(struct snd_pcm_substream *substream) 262 { 263 struct snd_pcm_runtime *runtime = substream->runtime; 264 struct pxa2xx_runtime_data *prtd = runtime->private_data; 265 266 dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE, 267 prtd->dma_desc_array, prtd->dma_desc_array_phys); 268 kfree(prtd); 269 return 0; 270 } 271 272 static int pxa2xx_pcm_mmap(struct snd_pcm_substream *substream, 273 struct vm_area_struct *vma) 274 { 275 struct snd_pcm_runtime *runtime = substream->runtime; 276 return dma_mmap_writecombine(substream->pcm->card->dev, vma, 277 runtime->dma_area, 278 runtime->dma_addr, 279 runtime->dma_bytes); 280 } 281 282 struct snd_pcm_ops pxa2xx_pcm_ops = { 283 .open = pxa2xx_pcm_open, 284 .close = pxa2xx_pcm_close, 285 .ioctl = snd_pcm_lib_ioctl, 286 .hw_params = pxa2xx_pcm_hw_params, 287 .hw_free = pxa2xx_pcm_hw_free, 288 .prepare = pxa2xx_pcm_prepare, 289 .trigger = pxa2xx_pcm_trigger, 290 .pointer = pxa2xx_pcm_pointer, 291 .mmap = pxa2xx_pcm_mmap, 292 }; 293 294 static int pxa2xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream) 295 { 296 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 297 struct snd_dma_buffer *buf = &substream->dma_buffer; 298 size_t size = pxa2xx_pcm_hardware.buffer_bytes_max; 299 buf->dev.type = SNDRV_DMA_TYPE_DEV; 300 buf->dev.dev = pcm->card->dev; 301 buf->private_data = NULL; 302 buf->area = dma_alloc_writecombine(pcm->card->dev, size, 303 &buf->addr, GFP_KERNEL); 304 if (!buf->area) 305 return -ENOMEM; 306 buf->bytes = size; 307 return 0; 308 } 309 310 static void pxa2xx_pcm_free_dma_buffers(struct snd_pcm *pcm) 311 { 312 struct snd_pcm_substream *substream; 313 struct snd_dma_buffer *buf; 314 int stream; 315 316 for (stream = 0; stream < 2; stream++) { 317 substream = pcm->streams[stream].substream; 318 if (!substream) 319 continue; 320 321 buf = &substream->dma_buffer; 322 if (!buf->area) 323 continue; 324 325 dma_free_writecombine(pcm->card->dev, buf->bytes, 326 buf->area, buf->addr); 327 buf->area = NULL; 328 } 329 } 330 331 static u64 pxa2xx_pcm_dmamask = DMA_32BIT_MASK; 332 333 int pxa2xx_pcm_new(struct snd_card *card, struct snd_soc_dai *dai, 334 struct snd_pcm *pcm) 335 { 336 int ret = 0; 337 338 if (!card->dev->dma_mask) 339 card->dev->dma_mask = &pxa2xx_pcm_dmamask; 340 if (!card->dev->coherent_dma_mask) 341 card->dev->coherent_dma_mask = DMA_32BIT_MASK; 342 343 if (dai->playback.channels_min) { 344 ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, 345 SNDRV_PCM_STREAM_PLAYBACK); 346 if (ret) 347 goto out; 348 } 349 350 if (dai->capture.channels_min) { 351 ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, 352 SNDRV_PCM_STREAM_CAPTURE); 353 if (ret) 354 goto out; 355 } 356 out: 357 return ret; 358 } 359 360 struct snd_soc_platform pxa2xx_soc_platform = { 361 .name = "pxa2xx-audio", 362 .pcm_ops = &pxa2xx_pcm_ops, 363 .pcm_new = pxa2xx_pcm_new, 364 .pcm_free = pxa2xx_pcm_free_dma_buffers, 365 }; 366 EXPORT_SYMBOL_GPL(pxa2xx_soc_platform); 367 368 MODULE_AUTHOR("Nicolas Pitre"); 369 MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module"); 370 MODULE_LICENSE("GPL"); 371