1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * atmel-pcm.c -- ALSA PCM interface for the Atmel atmel SoC. 4 * 5 * Copyright (C) 2005 SAN People 6 * Copyright (C) 2008 Atmel 7 * 8 * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com> 9 * 10 * Based on at91-pcm. by: 11 * Frank Mandarino <fmandarino@endrelia.com> 12 * Copyright 2006 Endrelia Technologies Inc. 13 * 14 * Based on pxa2xx-pcm.c by: 15 * 16 * Author: Nicolas Pitre 17 * Created: Nov 30, 2004 18 * Copyright: (C) 2004 MontaVista Software, Inc. 19 */ 20 21 #include <linux/module.h> 22 #include <linux/init.h> 23 #include <linux/platform_device.h> 24 #include <linux/slab.h> 25 #include <linux/dma-mapping.h> 26 #include <linux/atmel_pdc.h> 27 #include <linux/atmel-ssc.h> 28 29 #include <sound/core.h> 30 #include <sound/pcm.h> 31 #include <sound/pcm_params.h> 32 #include <sound/soc.h> 33 34 #include "atmel-pcm.h" 35 36 37 static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, 38 int stream) 39 { 40 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 41 struct snd_dma_buffer *buf = &substream->dma_buffer; 42 size_t size = ATMEL_SSC_DMABUF_SIZE; 43 44 buf->dev.type = SNDRV_DMA_TYPE_DEV; 45 buf->dev.dev = pcm->card->dev; 46 buf->private_data = NULL; 47 buf->area = dma_alloc_coherent(pcm->card->dev, size, 48 &buf->addr, GFP_KERNEL); 49 pr_debug("atmel-pcm: alloc dma buffer: area=%p, addr=%p, size=%zu\n", 50 (void *)buf->area, (void *)(long)buf->addr, size); 51 52 if (!buf->area) 53 return -ENOMEM; 54 55 buf->bytes = size; 56 return 0; 57 } 58 59 static int atmel_pcm_mmap(struct snd_pcm_substream *substream, 60 struct vm_area_struct *vma) 61 { 62 return remap_pfn_range(vma, vma->vm_start, 63 substream->dma_buffer.addr >> PAGE_SHIFT, 64 vma->vm_end - vma->vm_start, vma->vm_page_prot); 65 } 66 67 static int atmel_pcm_new(struct snd_soc_pcm_runtime *rtd) 68 { 69 struct snd_card *card = rtd->card->snd_card; 70 struct snd_pcm *pcm = rtd->pcm; 71 int ret; 72 73 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 74 if (ret) 75 return ret; 76 77 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 78 pr_debug("atmel-pcm: allocating PCM playback DMA buffer\n"); 79 ret = atmel_pcm_preallocate_dma_buffer(pcm, 80 SNDRV_PCM_STREAM_PLAYBACK); 81 if (ret) 82 goto out; 83 } 84 85 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) { 86 pr_debug("atmel-pcm: allocating PCM capture DMA buffer\n"); 87 ret = atmel_pcm_preallocate_dma_buffer(pcm, 88 SNDRV_PCM_STREAM_CAPTURE); 89 if (ret) 90 goto out; 91 } 92 out: 93 return ret; 94 } 95 96 static void atmel_pcm_free(struct snd_pcm *pcm) 97 { 98 struct snd_pcm_substream *substream; 99 struct snd_dma_buffer *buf; 100 int stream; 101 102 for (stream = 0; stream < 2; stream++) { 103 substream = pcm->streams[stream].substream; 104 if (!substream) 105 continue; 106 107 buf = &substream->dma_buffer; 108 if (!buf->area) 109 continue; 110 dma_free_coherent(pcm->card->dev, buf->bytes, 111 buf->area, buf->addr); 112 buf->area = NULL; 113 } 114 } 115 116 /*--------------------------------------------------------------------------*\ 117 * Hardware definition 118 \*--------------------------------------------------------------------------*/ 119 /* TODO: These values were taken from the AT91 platform driver, check 120 * them against real values for AT32 121 */ 122 static const struct snd_pcm_hardware atmel_pcm_hardware = { 123 .info = SNDRV_PCM_INFO_MMAP | 124 SNDRV_PCM_INFO_MMAP_VALID | 125 SNDRV_PCM_INFO_INTERLEAVED | 126 SNDRV_PCM_INFO_PAUSE, 127 .period_bytes_min = 32, 128 .period_bytes_max = 8192, 129 .periods_min = 2, 130 .periods_max = 1024, 131 .buffer_bytes_max = ATMEL_SSC_DMABUF_SIZE, 132 }; 133 134 135 /*--------------------------------------------------------------------------*\ 136 * Data types 137 \*--------------------------------------------------------------------------*/ 138 struct atmel_runtime_data { 139 struct atmel_pcm_dma_params *params; 140 dma_addr_t dma_buffer; /* physical address of dma buffer */ 141 dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */ 142 size_t period_size; 143 144 dma_addr_t period_ptr; /* physical address of next period */ 145 }; 146 147 /*--------------------------------------------------------------------------*\ 148 * ISR 149 \*--------------------------------------------------------------------------*/ 150 static void atmel_pcm_dma_irq(u32 ssc_sr, 151 struct snd_pcm_substream *substream) 152 { 153 struct atmel_runtime_data *prtd = substream->runtime->private_data; 154 struct atmel_pcm_dma_params *params = prtd->params; 155 static int count; 156 157 count++; 158 159 if (ssc_sr & params->mask->ssc_endbuf) { 160 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n", 161 substream->stream == SNDRV_PCM_STREAM_PLAYBACK 162 ? "underrun" : "overrun", 163 params->name, ssc_sr, count); 164 165 /* re-start the PDC */ 166 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 167 params->mask->pdc_disable); 168 prtd->period_ptr += prtd->period_size; 169 if (prtd->period_ptr >= prtd->dma_buffer_end) 170 prtd->period_ptr = prtd->dma_buffer; 171 172 ssc_writex(params->ssc->regs, params->pdc->xpr, 173 prtd->period_ptr); 174 ssc_writex(params->ssc->regs, params->pdc->xcr, 175 prtd->period_size / params->pdc_xfer_size); 176 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 177 params->mask->pdc_enable); 178 } 179 180 if (ssc_sr & params->mask->ssc_endx) { 181 /* Load the PDC next pointer and counter registers */ 182 prtd->period_ptr += prtd->period_size; 183 if (prtd->period_ptr >= prtd->dma_buffer_end) 184 prtd->period_ptr = prtd->dma_buffer; 185 186 ssc_writex(params->ssc->regs, params->pdc->xnpr, 187 prtd->period_ptr); 188 ssc_writex(params->ssc->regs, params->pdc->xncr, 189 prtd->period_size / params->pdc_xfer_size); 190 } 191 192 snd_pcm_period_elapsed(substream); 193 } 194 195 196 /*--------------------------------------------------------------------------*\ 197 * PCM operations 198 \*--------------------------------------------------------------------------*/ 199 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream, 200 struct snd_pcm_hw_params *params) 201 { 202 struct snd_pcm_runtime *runtime = substream->runtime; 203 struct atmel_runtime_data *prtd = runtime->private_data; 204 struct snd_soc_pcm_runtime *rtd = substream->private_data; 205 206 /* this may get called several times by oss emulation 207 * with different params */ 208 209 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 210 runtime->dma_bytes = params_buffer_bytes(params); 211 212 prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 213 prtd->params->dma_intr_handler = atmel_pcm_dma_irq; 214 215 prtd->dma_buffer = runtime->dma_addr; 216 prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes; 217 prtd->period_size = params_period_bytes(params); 218 219 pr_debug("atmel-pcm: " 220 "hw_params: DMA for %s initialized " 221 "(dma_bytes=%zu, period_size=%zu)\n", 222 prtd->params->name, 223 runtime->dma_bytes, 224 prtd->period_size); 225 return 0; 226 } 227 228 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream) 229 { 230 struct atmel_runtime_data *prtd = substream->runtime->private_data; 231 struct atmel_pcm_dma_params *params = prtd->params; 232 233 if (params != NULL) { 234 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 235 params->mask->pdc_disable); 236 prtd->params->dma_intr_handler = NULL; 237 } 238 239 return 0; 240 } 241 242 static int atmel_pcm_prepare(struct snd_pcm_substream *substream) 243 { 244 struct atmel_runtime_data *prtd = substream->runtime->private_data; 245 struct atmel_pcm_dma_params *params = prtd->params; 246 247 ssc_writex(params->ssc->regs, SSC_IDR, 248 params->mask->ssc_endx | params->mask->ssc_endbuf); 249 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 250 params->mask->pdc_disable); 251 return 0; 252 } 253 254 static int atmel_pcm_trigger(struct snd_pcm_substream *substream, 255 int cmd) 256 { 257 struct snd_pcm_runtime *rtd = substream->runtime; 258 struct atmel_runtime_data *prtd = rtd->private_data; 259 struct atmel_pcm_dma_params *params = prtd->params; 260 int ret = 0; 261 262 pr_debug("atmel-pcm:buffer_size = %ld," 263 "dma_area = %p, dma_bytes = %zu\n", 264 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes); 265 266 switch (cmd) { 267 case SNDRV_PCM_TRIGGER_START: 268 prtd->period_ptr = prtd->dma_buffer; 269 270 ssc_writex(params->ssc->regs, params->pdc->xpr, 271 prtd->period_ptr); 272 ssc_writex(params->ssc->regs, params->pdc->xcr, 273 prtd->period_size / params->pdc_xfer_size); 274 275 prtd->period_ptr += prtd->period_size; 276 ssc_writex(params->ssc->regs, params->pdc->xnpr, 277 prtd->period_ptr); 278 ssc_writex(params->ssc->regs, params->pdc->xncr, 279 prtd->period_size / params->pdc_xfer_size); 280 281 pr_debug("atmel-pcm: trigger: " 282 "period_ptr=%lx, xpr=%u, " 283 "xcr=%u, xnpr=%u, xncr=%u\n", 284 (unsigned long)prtd->period_ptr, 285 ssc_readx(params->ssc->regs, params->pdc->xpr), 286 ssc_readx(params->ssc->regs, params->pdc->xcr), 287 ssc_readx(params->ssc->regs, params->pdc->xnpr), 288 ssc_readx(params->ssc->regs, params->pdc->xncr)); 289 290 ssc_writex(params->ssc->regs, SSC_IER, 291 params->mask->ssc_endx | params->mask->ssc_endbuf); 292 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 293 params->mask->pdc_enable); 294 295 pr_debug("sr=%u imr=%u\n", 296 ssc_readx(params->ssc->regs, SSC_SR), 297 ssc_readx(params->ssc->regs, SSC_IER)); 298 break; /* SNDRV_PCM_TRIGGER_START */ 299 300 case SNDRV_PCM_TRIGGER_STOP: 301 case SNDRV_PCM_TRIGGER_SUSPEND: 302 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 303 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 304 params->mask->pdc_disable); 305 break; 306 307 case SNDRV_PCM_TRIGGER_RESUME: 308 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 309 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 310 params->mask->pdc_enable); 311 break; 312 313 default: 314 ret = -EINVAL; 315 } 316 317 return ret; 318 } 319 320 static snd_pcm_uframes_t atmel_pcm_pointer( 321 struct snd_pcm_substream *substream) 322 { 323 struct snd_pcm_runtime *runtime = substream->runtime; 324 struct atmel_runtime_data *prtd = runtime->private_data; 325 struct atmel_pcm_dma_params *params = prtd->params; 326 dma_addr_t ptr; 327 snd_pcm_uframes_t x; 328 329 ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr); 330 x = bytes_to_frames(runtime, ptr - prtd->dma_buffer); 331 332 if (x == runtime->buffer_size) 333 x = 0; 334 335 return x; 336 } 337 338 static int atmel_pcm_open(struct snd_pcm_substream *substream) 339 { 340 struct snd_pcm_runtime *runtime = substream->runtime; 341 struct atmel_runtime_data *prtd; 342 int ret = 0; 343 344 snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware); 345 346 /* ensure that buffer size is a multiple of period size */ 347 ret = snd_pcm_hw_constraint_integer(runtime, 348 SNDRV_PCM_HW_PARAM_PERIODS); 349 if (ret < 0) 350 goto out; 351 352 prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL); 353 if (prtd == NULL) { 354 ret = -ENOMEM; 355 goto out; 356 } 357 runtime->private_data = prtd; 358 359 out: 360 return ret; 361 } 362 363 static int atmel_pcm_close(struct snd_pcm_substream *substream) 364 { 365 struct atmel_runtime_data *prtd = substream->runtime->private_data; 366 367 kfree(prtd); 368 return 0; 369 } 370 371 static const struct snd_pcm_ops atmel_pcm_ops = { 372 .open = atmel_pcm_open, 373 .close = atmel_pcm_close, 374 .ioctl = snd_pcm_lib_ioctl, 375 .hw_params = atmel_pcm_hw_params, 376 .hw_free = atmel_pcm_hw_free, 377 .prepare = atmel_pcm_prepare, 378 .trigger = atmel_pcm_trigger, 379 .pointer = atmel_pcm_pointer, 380 .mmap = atmel_pcm_mmap, 381 }; 382 383 static struct snd_soc_component_driver atmel_soc_platform = { 384 .ops = &atmel_pcm_ops, 385 .pcm_new = atmel_pcm_new, 386 .pcm_free = atmel_pcm_free, 387 }; 388 389 int atmel_pcm_pdc_platform_register(struct device *dev) 390 { 391 return devm_snd_soc_register_component(dev, &atmel_soc_platform, 392 NULL, 0); 393 } 394 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register); 395 396 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>"); 397 MODULE_DESCRIPTION("Atmel PCM module"); 398 MODULE_LICENSE("GPL"); 399