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 = 32 * 1024,
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 int periods; /* period index of period_ptr */
81
82 /* PDC register save */
83 u32 pdc_xpr_save;
84 u32 pdc_xcr_save;
85 u32 pdc_xnpr_save;
86 u32 pdc_xncr_save;
87 };
88
89
90 /*--------------------------------------------------------------------------*\
91 * Helper functions
92 \*--------------------------------------------------------------------------*/
93 static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
94 int stream)
95 {
96 struct snd_pcm_substream *substream = pcm->streams[stream].substream;
97 struct snd_dma_buffer *buf = &substream->dma_buffer;
98 size_t size = atmel_pcm_hardware.buffer_bytes_max;
99
100 buf->dev.type = SNDRV_DMA_TYPE_DEV;
101 buf->dev.dev = pcm->card->dev;
102 buf->private_data = NULL;
103 buf->area = dma_alloc_coherent(pcm->card->dev, size,
104 &buf->addr, GFP_KERNEL);
105 pr_debug("atmel-pcm:"
106 "preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
107 (void *) buf->area,
108 (void *) buf->addr,
109 size);
110
111 if (!buf->area)
112 return -ENOMEM;
113
114 buf->bytes = size;
115 return 0;
116 }
117 /*--------------------------------------------------------------------------*\
118 * ISR
119 \*--------------------------------------------------------------------------*/
120 static void atmel_pcm_dma_irq(u32 ssc_sr,
121 struct snd_pcm_substream *substream)
122 {
123 struct atmel_runtime_data *prtd = substream->runtime->private_data;
124 struct atmel_pcm_dma_params *params = prtd->params;
125 static int count;
126
127 count++;
128
129 if (ssc_sr & params->mask->ssc_endbuf) {
130 pr_warning("atmel-pcm: buffer %s on %s"
131 " (SSC_SR=%#x, count=%d)\n",
132 substream->stream == SNDRV_PCM_STREAM_PLAYBACK
133 ? "underrun" : "overrun",
134 params->name, ssc_sr, count);
135
136 /* re-start the PDC */
137 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
138 params->mask->pdc_disable);
139 prtd->period_ptr += prtd->period_size;
140 if (prtd->period_ptr >= prtd->dma_buffer_end)
141 prtd->period_ptr = prtd->dma_buffer;
142
143 ssc_writex(params->ssc->regs, params->pdc->xpr,
144 prtd->period_ptr);
145 ssc_writex(params->ssc->regs, params->pdc->xcr,
146 prtd->period_size / params->pdc_xfer_size);
147 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
148 params->mask->pdc_enable);
149 }
150
151 if (ssc_sr & params->mask->ssc_endx) {
152 /* Load the PDC next pointer and counter registers */
153 prtd->period_ptr += prtd->period_size;
154 if (prtd->period_ptr >= prtd->dma_buffer_end)
155 prtd->period_ptr = prtd->dma_buffer;
156
157 ssc_writex(params->ssc->regs, params->pdc->xnpr,
158 prtd->period_ptr);
159 ssc_writex(params->ssc->regs, params->pdc->xncr,
160 prtd->period_size / params->pdc_xfer_size);
161 }
162
163 snd_pcm_period_elapsed(substream);
164 }
165
166
167 /*--------------------------------------------------------------------------*\
168 * PCM operations
169 \*--------------------------------------------------------------------------*/
170 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream,
171 struct snd_pcm_hw_params *params)
172 {
173 struct snd_pcm_runtime *runtime = substream->runtime;
174 struct atmel_runtime_data *prtd = runtime->private_data;
175 struct snd_soc_pcm_runtime *rtd = substream->private_data;
176
177 /* this may get called several times by oss emulation
178 * with different params */
179
180 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
181 runtime->dma_bytes = params_buffer_bytes(params);
182
183 prtd->params = rtd->dai->cpu_dai->dma_data;
184 prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
185
186 prtd->dma_buffer = runtime->dma_addr;
187 prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
188 prtd->period_size = params_period_bytes(params);
189
190 pr_debug("atmel-pcm: "
191 "hw_params: DMA for %s initialized "
192 "(dma_bytes=%u, period_size=%u)\n",
193 prtd->params->name,
194 runtime->dma_bytes,
195 prtd->period_size);
196 return 0;
197 }
198
199 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream)
200 {
201 struct atmel_runtime_data *prtd = substream->runtime->private_data;
202 struct atmel_pcm_dma_params *params = prtd->params;
203
204 if (params != NULL) {
205 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
206 params->mask->pdc_disable);
207 prtd->params->dma_intr_handler = NULL;
208 }
209
210 return 0;
211 }
212
213 static int atmel_pcm_prepare(struct snd_pcm_substream *substream)
214 {
215 struct atmel_runtime_data *prtd = substream->runtime->private_data;
216 struct atmel_pcm_dma_params *params = prtd->params;
217
218 ssc_writex(params->ssc->regs, SSC_IDR,
219 params->mask->ssc_endx | params->mask->ssc_endbuf);
220 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
221 params->mask->pdc_disable);
222 return 0;
223 }
224
225 static int atmel_pcm_trigger(struct snd_pcm_substream *substream,
226 int cmd)
227 {
228 struct snd_pcm_runtime *rtd = substream->runtime;
229 struct atmel_runtime_data *prtd = rtd->private_data;
230 struct atmel_pcm_dma_params *params = prtd->params;
231 int ret = 0;
232
233 pr_debug("atmel-pcm:buffer_size = %ld,"
234 "dma_area = %p, dma_bytes = %u\n",
235 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
236
237 switch (cmd) {
238 case SNDRV_PCM_TRIGGER_START:
239 prtd->period_ptr = prtd->dma_buffer;
240
241 ssc_writex(params->ssc->regs, params->pdc->xpr,
242 prtd->period_ptr);
243 ssc_writex(params->ssc->regs, params->pdc->xcr,
244 prtd->period_size / params->pdc_xfer_size);
245
246 prtd->period_ptr += prtd->period_size;
247 ssc_writex(params->ssc->regs, params->pdc->xnpr,
248 prtd->period_ptr);
249 ssc_writex(params->ssc->regs, params->pdc->xncr,
250 prtd->period_size / params->pdc_xfer_size);
251
252 pr_debug("atmel-pcm: trigger: "
253 "period_ptr=%lx, xpr=%u, "
254 "xcr=%u, xnpr=%u, xncr=%u\n",
255 (unsigned long)prtd->period_ptr,
256 ssc_readx(params->ssc->regs, params->pdc->xpr),
257 ssc_readx(params->ssc->regs, params->pdc->xcr),
258 ssc_readx(params->ssc->regs, params->pdc->xnpr),
259 ssc_readx(params->ssc->regs, params->pdc->xncr));
260
261 ssc_writex(params->ssc->regs, SSC_IER,
262 params->mask->ssc_endx | params->mask->ssc_endbuf);
263 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
264 params->mask->pdc_enable);
265
266 pr_debug("sr=%u imr=%u\n",
267 ssc_readx(params->ssc->regs, SSC_SR),
268 ssc_readx(params->ssc->regs, SSC_IER));
269 break; /* SNDRV_PCM_TRIGGER_START */
270
271 case SNDRV_PCM_TRIGGER_STOP:
272 case SNDRV_PCM_TRIGGER_SUSPEND:
273 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
274 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
275 params->mask->pdc_disable);
276 break;
277
278 case SNDRV_PCM_TRIGGER_RESUME:
279 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
280 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
281 params->mask->pdc_enable);
282 break;
283
284 default:
285 ret = -EINVAL;
286 }
287
288 return ret;
289 }
290
291 static snd_pcm_uframes_t atmel_pcm_pointer(
292 struct snd_pcm_substream *substream)
293 {
294 struct snd_pcm_runtime *runtime = substream->runtime;
295 struct atmel_runtime_data *prtd = runtime->private_data;
296 struct atmel_pcm_dma_params *params = prtd->params;
297 dma_addr_t ptr;
298 snd_pcm_uframes_t x;
299
300 ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
301 x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
302
303 if (x == runtime->buffer_size)
304 x = 0;
305
306 return x;
307 }
308
309 static int atmel_pcm_open(struct snd_pcm_substream *substream)
310 {
311 struct snd_pcm_runtime *runtime = substream->runtime;
312 struct atmel_runtime_data *prtd;
313 int ret = 0;
314
315 snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
316
317 /* ensure that buffer size is a multiple of period size */
318 ret = snd_pcm_hw_constraint_integer(runtime,
319 SNDRV_PCM_HW_PARAM_PERIODS);
320 if (ret < 0)
321 goto out;
322
323 prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
324 if (prtd == NULL) {
325 ret = -ENOMEM;
326 goto out;
327 }
328 runtime->private_data = prtd;
329
330 out:
331 return ret;
332 }
333
334 static int atmel_pcm_close(struct snd_pcm_substream *substream)
335 {
336 struct atmel_runtime_data *prtd = substream->runtime->private_data;
337
338 kfree(prtd);
339 return 0;
340 }
341
342 static int atmel_pcm_mmap(struct snd_pcm_substream *substream,
343 struct vm_area_struct *vma)
344 {
345 return remap_pfn_range(vma, vma->vm_start,
346 substream->dma_buffer.addr >> PAGE_SHIFT,
347 vma->vm_end - vma->vm_start, vma->vm_page_prot);
348 }
349
350 static struct snd_pcm_ops atmel_pcm_ops = {
351 .open = atmel_pcm_open,
352 .close = atmel_pcm_close,
353 .ioctl = snd_pcm_lib_ioctl,
354 .hw_params = atmel_pcm_hw_params,
355 .hw_free = atmel_pcm_hw_free,
356 .prepare = atmel_pcm_prepare,
357 .trigger = atmel_pcm_trigger,
358 .pointer = atmel_pcm_pointer,
359 .mmap = atmel_pcm_mmap,
360 };
361
362
363 /*--------------------------------------------------------------------------*\
364 * ASoC platform driver
365 \*--------------------------------------------------------------------------*/
366 static u64 atmel_pcm_dmamask = 0xffffffff;
367
368 static int atmel_pcm_new(struct snd_card *card,
369 struct snd_soc_dai *dai, struct snd_pcm *pcm)
370 {
371 int ret = 0;
372
373 if (!card->dev->dma_mask)
374 card->dev->dma_mask = &atmel_pcm_dmamask;
375 if (!card->dev->coherent_dma_mask)
376 card->dev->coherent_dma_mask = 0xffffffff;
377
378 if (dai->playback.channels_min) {
379 ret = atmel_pcm_preallocate_dma_buffer(pcm,
380 SNDRV_PCM_STREAM_PLAYBACK);
381 if (ret)
382 goto out;
383 }
384
385 if (dai->capture.channels_min) {
386 pr_debug("at32-pcm:"
387 "Allocating PCM capture DMA buffer\n");
388 ret = atmel_pcm_preallocate_dma_buffer(pcm,
389 SNDRV_PCM_STREAM_CAPTURE);
390 if (ret)
391 goto out;
392 }
393 out:
394 return ret;
395 }
396
397 static void atmel_pcm_free_dma_buffers(struct snd_pcm *pcm)
398 {
399 struct snd_pcm_substream *substream;
400 struct snd_dma_buffer *buf;
401 int stream;
402
403 for (stream = 0; stream < 2; stream++) {
404 substream = pcm->streams[stream].substream;
405 if (!substream)
406 continue;
407
408 buf = &substream->dma_buffer;
409 if (!buf->area)
410 continue;
411 dma_free_coherent(pcm->card->dev, buf->bytes,
412 buf->area, buf->addr);
413 buf->area = NULL;
414 }
415 }
416
417 #ifdef CONFIG_PM
418 static int atmel_pcm_suspend(struct snd_soc_dai *dai)
419 {
420 struct snd_pcm_runtime *runtime = dai->runtime;
421 struct atmel_runtime_data *prtd;
422 struct atmel_pcm_dma_params *params;
423
424 if (!runtime)
425 return 0;
426
427 prtd = runtime->private_data;
428 params = prtd->params;
429
430 /* disable the PDC and save the PDC registers */
431
432 ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable);
433
434 prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
435 prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
436 prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
437 prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
438
439 return 0;
440 }
441
442 static int atmel_pcm_resume(struct snd_soc_dai *dai)
443 {
444 struct snd_pcm_runtime *runtime = dai->runtime;
445 struct atmel_runtime_data *prtd;
446 struct atmel_pcm_dma_params *params;
447
448 if (!runtime)
449 return 0;
450
451 prtd = runtime->private_data;
452 params = prtd->params;
453
454 /* restore the PDC registers and enable the PDC */
455 ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
456 ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
457 ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
458 ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
459
460 ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable);
461 return 0;
462 }
463 #else
464 #define atmel_pcm_suspend NULL
465 #define atmel_pcm_resume NULL
466 #endif
467
468 struct snd_soc_platform atmel_soc_platform = {
469 .name = "atmel-audio",
470 .pcm_ops = &atmel_pcm_ops,
471 .pcm_new = atmel_pcm_new,
472 .pcm_free = atmel_pcm_free_dma_buffers,
473 .suspend = atmel_pcm_suspend,
474 .resume = atmel_pcm_resume,
475 };
476 EXPORT_SYMBOL_GPL(atmel_soc_platform);
477
478 static int __init atmel_pcm_modinit(void)
479 {
480 return snd_soc_register_platform(&atmel_soc_platform);
481 }
482 module_init(atmel_pcm_modinit);
483
484 static void __exit atmel_pcm_modexit(void)
485 {
486 snd_soc_unregister_platform(&atmel_soc_platform);
487 }
488 module_exit(atmel_pcm_modexit);
489
490 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
491 MODULE_DESCRIPTION("Atmel PCM module");
492 MODULE_LICENSE("GPL");
493
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