1 /*
2 * s3c24xx-pcm.c -- ALSA Soc Audio Layer
3 *
4 * (c) 2006 Wolfson Microelectronics PLC.
5 * Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
6 *
7 * (c) 2004-2005 Simtec Electronics
8 * http://armlinux.simtec.co.uk/
9 * Ben Dooks <ben@simtec.co.uk>
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version.
15 */
16
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/io.h>
20 #include <linux/platform_device.h>
21 #include <linux/slab.h>
22 #include <linux/dma-mapping.h>
23
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 #include <sound/soc.h>
28
29 #include <asm/dma.h>
30 #include <mach/hardware.h>
31 #include <mach/dma.h>
32 #include <mach/audio.h>
33
34 #include "s3c24xx-pcm.h"
35
36 #define S3C24XX_PCM_DEBUG 0
37 #if S3C24XX_PCM_DEBUG
38 #define DBG(x...) printk(KERN_DEBUG "s3c24xx-pcm: " x)
39 #else
40 #define DBG(x...)
41 #endif
42
43 static const struct snd_pcm_hardware s3c24xx_pcm_hardware = {
44 .info = SNDRV_PCM_INFO_INTERLEAVED |
45 SNDRV_PCM_INFO_BLOCK_TRANSFER |
46 SNDRV_PCM_INFO_MMAP |
47 SNDRV_PCM_INFO_MMAP_VALID |
48 SNDRV_PCM_INFO_PAUSE |
49 SNDRV_PCM_INFO_RESUME,
50 .formats = SNDRV_PCM_FMTBIT_S16_LE |
51 SNDRV_PCM_FMTBIT_U16_LE |
52 SNDRV_PCM_FMTBIT_U8 |
53 SNDRV_PCM_FMTBIT_S8,
54 .channels_min = 2,
55 .channels_max = 2,
56 .buffer_bytes_max = 128*1024,
57 .period_bytes_min = PAGE_SIZE,
58 .period_bytes_max = PAGE_SIZE*2,
59 .periods_min = 2,
60 .periods_max = 128,
61 .fifo_size = 32,
62 };
63
64 struct s3c24xx_runtime_data {
65 spinlock_t lock;
66 int state;
67 unsigned int dma_loaded;
68 unsigned int dma_limit;
69 unsigned int dma_period;
70 dma_addr_t dma_start;
71 dma_addr_t dma_pos;
72 dma_addr_t dma_end;
73 struct s3c24xx_pcm_dma_params *params;
74 };
75
76 /* s3c24xx_pcm_enqueue
77 *
78 * place a dma buffer onto the queue for the dma system
79 * to handle.
80 */
s3c24xx_pcm_enqueue(struct snd_pcm_substream * substream)81 static void s3c24xx_pcm_enqueue(struct snd_pcm_substream *substream)
82 {
83 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
84 dma_addr_t pos = prtd->dma_pos;
85 int ret;
86
87 DBG("Entered %s\n", __func__);
88
89 while (prtd->dma_loaded < prtd->dma_limit) {
90 unsigned long len = prtd->dma_period;
91
92 DBG("dma_loaded: %d\n", prtd->dma_loaded);
93
94 if ((pos + len) > prtd->dma_end) {
95 len = prtd->dma_end - pos;
96 DBG(KERN_DEBUG "%s: corrected dma len %ld\n",
97 __func__, len);
98 }
99
100 ret = s3c2410_dma_enqueue(prtd->params->channel,
101 substream, pos, len);
102
103 if (ret == 0) {
104 prtd->dma_loaded++;
105 pos += prtd->dma_period;
106 if (pos >= prtd->dma_end)
107 pos = prtd->dma_start;
108 } else
109 break;
110 }
111
112 prtd->dma_pos = pos;
113 }
114
s3c24xx_audio_buffdone(struct s3c2410_dma_chan * channel,void * dev_id,int size,enum s3c2410_dma_buffresult result)115 static void s3c24xx_audio_buffdone(struct s3c2410_dma_chan *channel,
116 void *dev_id, int size,
117 enum s3c2410_dma_buffresult result)
118 {
119 struct snd_pcm_substream *substream = dev_id;
120 struct s3c24xx_runtime_data *prtd;
121
122 DBG("Entered %s\n", __func__);
123
124 if (result == S3C2410_RES_ABORT || result == S3C2410_RES_ERR)
125 return;
126
127 prtd = substream->runtime->private_data;
128
129 if (substream)
130 snd_pcm_period_elapsed(substream);
131
132 spin_lock(&prtd->lock);
133 if (prtd->state & ST_RUNNING) {
134 prtd->dma_loaded--;
135 s3c24xx_pcm_enqueue(substream);
136 }
137
138 spin_unlock(&prtd->lock);
139 }
140
s3c24xx_pcm_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)141 static int s3c24xx_pcm_hw_params(struct snd_pcm_substream *substream,
142 struct snd_pcm_hw_params *params)
143 {
144 struct snd_pcm_runtime *runtime = substream->runtime;
145 struct s3c24xx_runtime_data *prtd = runtime->private_data;
146 struct snd_soc_pcm_runtime *rtd = substream->private_data;
147 struct s3c24xx_pcm_dma_params *dma = rtd->dai->cpu_dai->dma_data;
148 unsigned long totbytes = params_buffer_bytes(params);
149 int ret = 0;
150
151 DBG("Entered %s\n", __func__);
152
153 /* return if this is a bufferless transfer e.g.
154 * codec <--> BT codec or GSM modem -- lg FIXME */
155 if (!dma)
156 return 0;
157
158 /* this may get called several times by oss emulation
159 * with different params -HW */
160 if (prtd->params == NULL) {
161 /* prepare DMA */
162 prtd->params = dma;
163
164 DBG("params %p, client %p, channel %d\n", prtd->params,
165 prtd->params->client, prtd->params->channel);
166
167 ret = s3c2410_dma_request(prtd->params->channel,
168 prtd->params->client, NULL);
169
170 if (ret < 0) {
171 DBG(KERN_ERR "failed to get dma channel\n");
172 return ret;
173 }
174 }
175
176 s3c2410_dma_set_buffdone_fn(prtd->params->channel,
177 s3c24xx_audio_buffdone);
178
179 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
180
181 runtime->dma_bytes = totbytes;
182
183 spin_lock_irq(&prtd->lock);
184 prtd->dma_loaded = 0;
185 prtd->dma_limit = runtime->hw.periods_min;
186 prtd->dma_period = params_period_bytes(params);
187 prtd->dma_start = runtime->dma_addr;
188 prtd->dma_pos = prtd->dma_start;
189 prtd->dma_end = prtd->dma_start + totbytes;
190 spin_unlock_irq(&prtd->lock);
191
192 return 0;
193 }
194
s3c24xx_pcm_hw_free(struct snd_pcm_substream * substream)195 static int s3c24xx_pcm_hw_free(struct snd_pcm_substream *substream)
196 {
197 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
198
199 DBG("Entered %s\n", __func__);
200
201 /* TODO - do we need to ensure DMA flushed */
202 snd_pcm_set_runtime_buffer(substream, NULL);
203
204 if (prtd->params) {
205 s3c2410_dma_free(prtd->params->channel, prtd->params->client);
206 prtd->params = NULL;
207 }
208
209 return 0;
210 }
211
s3c24xx_pcm_prepare(struct snd_pcm_substream * substream)212 static int s3c24xx_pcm_prepare(struct snd_pcm_substream *substream)
213 {
214 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
215 int ret = 0;
216
217 DBG("Entered %s\n", __func__);
218
219 /* return if this is a bufferless transfer e.g.
220 * codec <--> BT codec or GSM modem -- lg FIXME */
221 if (!prtd->params)
222 return 0;
223
224 /* channel needs configuring for mem=>device, increment memory addr,
225 * sync to pclk, half-word transfers to the IIS-FIFO. */
226 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
227 s3c2410_dma_devconfig(prtd->params->channel,
228 S3C2410_DMASRC_MEM, S3C2410_DISRCC_INC |
229 S3C2410_DISRCC_APB, prtd->params->dma_addr);
230
231 s3c2410_dma_config(prtd->params->channel,
232 prtd->params->dma_size,
233 S3C2410_DCON_SYNC_PCLK |
234 S3C2410_DCON_HANDSHAKE);
235 } else {
236 s3c2410_dma_config(prtd->params->channel,
237 prtd->params->dma_size,
238 S3C2410_DCON_HANDSHAKE |
239 S3C2410_DCON_SYNC_PCLK);
240
241 s3c2410_dma_devconfig(prtd->params->channel,
242 S3C2410_DMASRC_HW, 0x3,
243 prtd->params->dma_addr);
244 }
245
246 /* flush the DMA channel */
247 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
248 prtd->dma_loaded = 0;
249 prtd->dma_pos = prtd->dma_start;
250
251 /* enqueue dma buffers */
252 s3c24xx_pcm_enqueue(substream);
253
254 return ret;
255 }
256
s3c24xx_pcm_trigger(struct snd_pcm_substream * substream,int cmd)257 static int s3c24xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
258 {
259 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
260 int ret = 0;
261
262 DBG("Entered %s\n", __func__);
263
264 spin_lock(&prtd->lock);
265
266 switch (cmd) {
267 case SNDRV_PCM_TRIGGER_START:
268 case SNDRV_PCM_TRIGGER_RESUME:
269 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
270 prtd->state |= ST_RUNNING;
271 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);
272 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STARTED);
273 break;
274
275 case SNDRV_PCM_TRIGGER_STOP:
276 case SNDRV_PCM_TRIGGER_SUSPEND:
277 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
278 prtd->state &= ~ST_RUNNING;
279 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);
280 break;
281
282 default:
283 ret = -EINVAL;
284 break;
285 }
286
287 spin_unlock(&prtd->lock);
288
289 return ret;
290 }
291
292 static snd_pcm_uframes_t
s3c24xx_pcm_pointer(struct snd_pcm_substream * substream)293 s3c24xx_pcm_pointer(struct snd_pcm_substream *substream)
294 {
295 struct snd_pcm_runtime *runtime = substream->runtime;
296 struct s3c24xx_runtime_data *prtd = runtime->private_data;
297 unsigned long res;
298 dma_addr_t src, dst;
299
300 DBG("Entered %s\n", __func__);
301
302 spin_lock(&prtd->lock);
303 s3c2410_dma_getposition(prtd->params->channel, &src, &dst);
304
305 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
306 res = dst - prtd->dma_start;
307 else
308 res = src - prtd->dma_start;
309
310 spin_unlock(&prtd->lock);
311
312 DBG("Pointer %x %x\n", src, dst);
313
314 /* we seem to be getting the odd error from the pcm library due
315 * to out-of-bounds pointers. this is maybe due to the dma engine
316 * not having loaded the new values for the channel before being
317 * callled... (todo - fix )
318 */
319
320 if (res >= snd_pcm_lib_buffer_bytes(substream)) {
321 if (res == snd_pcm_lib_buffer_bytes(substream))
322 res = 0;
323 }
324
325 return bytes_to_frames(substream->runtime, res);
326 }
327
s3c24xx_pcm_open(struct snd_pcm_substream * substream)328 static int s3c24xx_pcm_open(struct snd_pcm_substream *substream)
329 {
330 struct snd_pcm_runtime *runtime = substream->runtime;
331 struct s3c24xx_runtime_data *prtd;
332
333 DBG("Entered %s\n", __func__);
334
335 snd_soc_set_runtime_hwparams(substream, &s3c24xx_pcm_hardware);
336
337 prtd = kzalloc(sizeof(struct s3c24xx_runtime_data), GFP_KERNEL);
338 if (prtd == NULL)
339 return -ENOMEM;
340
341 spin_lock_init(&prtd->lock);
342
343 runtime->private_data = prtd;
344 return 0;
345 }
346
s3c24xx_pcm_close(struct snd_pcm_substream * substream)347 static int s3c24xx_pcm_close(struct snd_pcm_substream *substream)
348 {
349 struct snd_pcm_runtime *runtime = substream->runtime;
350 struct s3c24xx_runtime_data *prtd = runtime->private_data;
351
352 DBG("Entered %s\n", __func__);
353
354 if (!prtd)
355 DBG("s3c24xx_pcm_close called with prtd == NULL\n");
356
357 kfree(prtd);
358
359 return 0;
360 }
361
s3c24xx_pcm_mmap(struct snd_pcm_substream * substream,struct vm_area_struct * vma)362 static int s3c24xx_pcm_mmap(struct snd_pcm_substream *substream,
363 struct vm_area_struct *vma)
364 {
365 struct snd_pcm_runtime *runtime = substream->runtime;
366
367 DBG("Entered %s\n", __func__);
368
369 return dma_mmap_writecombine(substream->pcm->card->dev, vma,
370 runtime->dma_area,
371 runtime->dma_addr,
372 runtime->dma_bytes);
373 }
374
375 static struct snd_pcm_ops s3c24xx_pcm_ops = {
376 .open = s3c24xx_pcm_open,
377 .close = s3c24xx_pcm_close,
378 .ioctl = snd_pcm_lib_ioctl,
379 .hw_params = s3c24xx_pcm_hw_params,
380 .hw_free = s3c24xx_pcm_hw_free,
381 .prepare = s3c24xx_pcm_prepare,
382 .trigger = s3c24xx_pcm_trigger,
383 .pointer = s3c24xx_pcm_pointer,
384 .mmap = s3c24xx_pcm_mmap,
385 };
386
s3c24xx_pcm_preallocate_dma_buffer(struct snd_pcm * pcm,int stream)387 static int s3c24xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
388 {
389 struct snd_pcm_substream *substream = pcm->streams[stream].substream;
390 struct snd_dma_buffer *buf = &substream->dma_buffer;
391 size_t size = s3c24xx_pcm_hardware.buffer_bytes_max;
392
393 DBG("Entered %s\n", __func__);
394
395 buf->dev.type = SNDRV_DMA_TYPE_DEV;
396 buf->dev.dev = pcm->card->dev;
397 buf->private_data = NULL;
398 buf->area = dma_alloc_writecombine(pcm->card->dev, size,
399 &buf->addr, GFP_KERNEL);
400 if (!buf->area)
401 return -ENOMEM;
402 buf->bytes = size;
403 return 0;
404 }
405
s3c24xx_pcm_free_dma_buffers(struct snd_pcm * pcm)406 static void s3c24xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
407 {
408 struct snd_pcm_substream *substream;
409 struct snd_dma_buffer *buf;
410 int stream;
411
412 DBG("Entered %s\n", __func__);
413
414 for (stream = 0; stream < 2; stream++) {
415 substream = pcm->streams[stream].substream;
416 if (!substream)
417 continue;
418
419 buf = &substream->dma_buffer;
420 if (!buf->area)
421 continue;
422
423 dma_free_writecombine(pcm->card->dev, buf->bytes,
424 buf->area, buf->addr);
425 buf->area = NULL;
426 }
427 }
428
429 static u64 s3c24xx_pcm_dmamask = DMA_32BIT_MASK;
430
s3c24xx_pcm_new(struct snd_card * card,struct snd_soc_dai * dai,struct snd_pcm * pcm)431 static int s3c24xx_pcm_new(struct snd_card *card,
432 struct snd_soc_dai *dai, struct snd_pcm *pcm)
433 {
434 int ret = 0;
435
436 DBG("Entered %s\n", __func__);
437
438 if (!card->dev->dma_mask)
439 card->dev->dma_mask = &s3c24xx_pcm_dmamask;
440 if (!card->dev->coherent_dma_mask)
441 card->dev->coherent_dma_mask = 0xffffffff;
442
443 if (dai->playback.channels_min) {
444 ret = s3c24xx_pcm_preallocate_dma_buffer(pcm,
445 SNDRV_PCM_STREAM_PLAYBACK);
446 if (ret)
447 goto out;
448 }
449
450 if (dai->capture.channels_min) {
451 ret = s3c24xx_pcm_preallocate_dma_buffer(pcm,
452 SNDRV_PCM_STREAM_CAPTURE);
453 if (ret)
454 goto out;
455 }
456 out:
457 return ret;
458 }
459
460 struct snd_soc_platform s3c24xx_soc_platform = {
461 .name = "s3c24xx-audio",
462 .pcm_ops = &s3c24xx_pcm_ops,
463 .pcm_new = s3c24xx_pcm_new,
464 .pcm_free = s3c24xx_pcm_free_dma_buffers,
465 };
466 EXPORT_SYMBOL_GPL(s3c24xx_soc_platform);
467
s3c24xx_soc_platform_init(void)468 static int __init s3c24xx_soc_platform_init(void)
469 {
470 return snd_soc_register_platform(&s3c24xx_soc_platform);
471 }
472 module_init(s3c24xx_soc_platform_init);
473
s3c24xx_soc_platform_exit(void)474 static void __exit s3c24xx_soc_platform_exit(void)
475 {
476 snd_soc_unregister_platform(&s3c24xx_soc_platform);
477 }
478 module_exit(s3c24xx_soc_platform_exit);
479
480 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
481 MODULE_DESCRIPTION("Samsung S3C24XX PCM DMA module");
482 MODULE_LICENSE("GPL");
483