2 * s3c24xx-pcm.c -- ALSA Soc Audio Layer
4 * (c) 2006 Wolfson Microelectronics PLC.
5 * Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
7 * Copyright 2004-2005 Simtec Electronics
8 * http://armlinux.simtec.co.uk/
9 * Ben Dooks <ben@simtec.co.uk>
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.
17 #include <linux/module.h>
18 #include <linux/init.h>
20 #include <linux/platform_device.h>
21 #include <linux/slab.h>
22 #include <linux/dma-mapping.h>
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 #include <sound/soc.h>
30 #include <mach/hardware.h>
32 #include <plat/audio.h>
34 #include "s3c24xx-pcm.h"
36 static const struct snd_pcm_hardware s3c24xx_pcm_hardware = {
37 .info = SNDRV_PCM_INFO_INTERLEAVED |
38 SNDRV_PCM_INFO_BLOCK_TRANSFER |
40 SNDRV_PCM_INFO_MMAP_VALID |
41 SNDRV_PCM_INFO_PAUSE |
42 SNDRV_PCM_INFO_RESUME,
43 .formats = SNDRV_PCM_FMTBIT_S16_LE |
44 SNDRV_PCM_FMTBIT_U16_LE |
49 .buffer_bytes_max = 128*1024,
50 .period_bytes_min = PAGE_SIZE,
51 .period_bytes_max = PAGE_SIZE*2,
57 struct s3c24xx_runtime_data {
60 unsigned int dma_loaded;
61 unsigned int dma_limit;
62 unsigned int dma_period;
66 struct s3c24xx_pcm_dma_params *params;
69 /* s3c24xx_pcm_enqueue
71 * place a dma buffer onto the queue for the dma system
74 static void s3c24xx_pcm_enqueue(struct snd_pcm_substream *substream)
76 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
77 dma_addr_t pos = prtd->dma_pos;
80 pr_debug("Entered %s\n", __func__);
82 while (prtd->dma_loaded < prtd->dma_limit) {
83 unsigned long len = prtd->dma_period;
85 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
87 if ((pos + len) > prtd->dma_end) {
88 len = prtd->dma_end - pos;
89 pr_debug(KERN_DEBUG "%s: corrected dma len %ld\n",
93 ret = s3c2410_dma_enqueue(prtd->params->channel,
98 pos += prtd->dma_period;
99 if (pos >= prtd->dma_end)
100 pos = prtd->dma_start;
108 static void s3c24xx_audio_buffdone(struct s3c2410_dma_chan *channel,
109 void *dev_id, int size,
110 enum s3c2410_dma_buffresult result)
112 struct snd_pcm_substream *substream = dev_id;
113 struct s3c24xx_runtime_data *prtd;
115 pr_debug("Entered %s\n", __func__);
117 if (result == S3C2410_RES_ABORT || result == S3C2410_RES_ERR)
120 prtd = substream->runtime->private_data;
123 snd_pcm_period_elapsed(substream);
125 spin_lock(&prtd->lock);
126 if (prtd->state & ST_RUNNING) {
128 s3c24xx_pcm_enqueue(substream);
131 spin_unlock(&prtd->lock);
134 static int s3c24xx_pcm_hw_params(struct snd_pcm_substream *substream,
135 struct snd_pcm_hw_params *params)
137 struct snd_pcm_runtime *runtime = substream->runtime;
138 struct s3c24xx_runtime_data *prtd = runtime->private_data;
139 struct snd_soc_pcm_runtime *rtd = substream->private_data;
140 struct s3c24xx_pcm_dma_params *dma = rtd->dai->cpu_dai->dma_data;
141 unsigned long totbytes = params_buffer_bytes(params);
144 pr_debug("Entered %s\n", __func__);
146 /* return if this is a bufferless transfer e.g.
147 * codec <--> BT codec or GSM modem -- lg FIXME */
151 /* this may get called several times by oss emulation
152 * with different params -HW */
153 if (prtd->params == NULL) {
157 pr_debug("params %p, client %p, channel %d\n", prtd->params,
158 prtd->params->client, prtd->params->channel);
160 ret = s3c2410_dma_request(prtd->params->channel,
161 prtd->params->client, NULL);
164 printk(KERN_ERR "failed to get dma channel\n");
169 s3c2410_dma_set_buffdone_fn(prtd->params->channel,
170 s3c24xx_audio_buffdone);
172 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
174 runtime->dma_bytes = totbytes;
176 spin_lock_irq(&prtd->lock);
177 prtd->dma_loaded = 0;
178 prtd->dma_limit = runtime->hw.periods_min;
179 prtd->dma_period = params_period_bytes(params);
180 prtd->dma_start = runtime->dma_addr;
181 prtd->dma_pos = prtd->dma_start;
182 prtd->dma_end = prtd->dma_start + totbytes;
183 spin_unlock_irq(&prtd->lock);
188 static int s3c24xx_pcm_hw_free(struct snd_pcm_substream *substream)
190 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
192 pr_debug("Entered %s\n", __func__);
194 /* TODO - do we need to ensure DMA flushed */
195 snd_pcm_set_runtime_buffer(substream, NULL);
198 s3c2410_dma_free(prtd->params->channel, prtd->params->client);
205 static int s3c24xx_pcm_prepare(struct snd_pcm_substream *substream)
207 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
210 pr_debug("Entered %s\n", __func__);
212 /* return if this is a bufferless transfer e.g.
213 * codec <--> BT codec or GSM modem -- lg FIXME */
217 /* channel needs configuring for mem=>device, increment memory addr,
218 * sync to pclk, half-word transfers to the IIS-FIFO. */
219 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
220 s3c2410_dma_devconfig(prtd->params->channel,
221 S3C2410_DMASRC_MEM, S3C2410_DISRCC_INC |
222 S3C2410_DISRCC_APB, prtd->params->dma_addr);
224 s3c2410_dma_config(prtd->params->channel,
225 prtd->params->dma_size,
226 S3C2410_DCON_SYNC_PCLK |
227 S3C2410_DCON_HANDSHAKE);
229 s3c2410_dma_config(prtd->params->channel,
230 prtd->params->dma_size,
231 S3C2410_DCON_HANDSHAKE |
232 S3C2410_DCON_SYNC_PCLK);
234 s3c2410_dma_devconfig(prtd->params->channel,
235 S3C2410_DMASRC_HW, 0x3,
236 prtd->params->dma_addr);
239 /* flush the DMA channel */
240 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
241 prtd->dma_loaded = 0;
242 prtd->dma_pos = prtd->dma_start;
244 /* enqueue dma buffers */
245 s3c24xx_pcm_enqueue(substream);
250 static int s3c24xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
252 struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
255 pr_debug("Entered %s\n", __func__);
257 spin_lock(&prtd->lock);
260 case SNDRV_PCM_TRIGGER_START:
261 case SNDRV_PCM_TRIGGER_RESUME:
262 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
263 prtd->state |= ST_RUNNING;
264 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);
265 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STARTED);
268 case SNDRV_PCM_TRIGGER_STOP:
269 case SNDRV_PCM_TRIGGER_SUSPEND:
270 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
271 prtd->state &= ~ST_RUNNING;
272 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);
280 spin_unlock(&prtd->lock);
285 static snd_pcm_uframes_t
286 s3c24xx_pcm_pointer(struct snd_pcm_substream *substream)
288 struct snd_pcm_runtime *runtime = substream->runtime;
289 struct s3c24xx_runtime_data *prtd = runtime->private_data;
293 pr_debug("Entered %s\n", __func__);
295 spin_lock(&prtd->lock);
296 s3c2410_dma_getposition(prtd->params->channel, &src, &dst);
298 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
299 res = dst - prtd->dma_start;
301 res = src - prtd->dma_start;
303 spin_unlock(&prtd->lock);
305 pr_debug("Pointer %x %x\n", src, dst);
307 /* we seem to be getting the odd error from the pcm library due
308 * to out-of-bounds pointers. this is maybe due to the dma engine
309 * not having loaded the new values for the channel before being
310 * callled... (todo - fix )
313 if (res >= snd_pcm_lib_buffer_bytes(substream)) {
314 if (res == snd_pcm_lib_buffer_bytes(substream))
318 return bytes_to_frames(substream->runtime, res);
321 static int s3c24xx_pcm_open(struct snd_pcm_substream *substream)
323 struct snd_pcm_runtime *runtime = substream->runtime;
324 struct s3c24xx_runtime_data *prtd;
326 pr_debug("Entered %s\n", __func__);
328 snd_soc_set_runtime_hwparams(substream, &s3c24xx_pcm_hardware);
330 prtd = kzalloc(sizeof(struct s3c24xx_runtime_data), GFP_KERNEL);
334 spin_lock_init(&prtd->lock);
336 runtime->private_data = prtd;
340 static int s3c24xx_pcm_close(struct snd_pcm_substream *substream)
342 struct snd_pcm_runtime *runtime = substream->runtime;
343 struct s3c24xx_runtime_data *prtd = runtime->private_data;
345 pr_debug("Entered %s\n", __func__);
348 pr_debug("s3c24xx_pcm_close called with prtd == NULL\n");
355 static int s3c24xx_pcm_mmap(struct snd_pcm_substream *substream,
356 struct vm_area_struct *vma)
358 struct snd_pcm_runtime *runtime = substream->runtime;
360 pr_debug("Entered %s\n", __func__);
362 return dma_mmap_writecombine(substream->pcm->card->dev, vma,
368 static struct snd_pcm_ops s3c24xx_pcm_ops = {
369 .open = s3c24xx_pcm_open,
370 .close = s3c24xx_pcm_close,
371 .ioctl = snd_pcm_lib_ioctl,
372 .hw_params = s3c24xx_pcm_hw_params,
373 .hw_free = s3c24xx_pcm_hw_free,
374 .prepare = s3c24xx_pcm_prepare,
375 .trigger = s3c24xx_pcm_trigger,
376 .pointer = s3c24xx_pcm_pointer,
377 .mmap = s3c24xx_pcm_mmap,
380 static int s3c24xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
382 struct snd_pcm_substream *substream = pcm->streams[stream].substream;
383 struct snd_dma_buffer *buf = &substream->dma_buffer;
384 size_t size = s3c24xx_pcm_hardware.buffer_bytes_max;
386 pr_debug("Entered %s\n", __func__);
388 buf->dev.type = SNDRV_DMA_TYPE_DEV;
389 buf->dev.dev = pcm->card->dev;
390 buf->private_data = NULL;
391 buf->area = dma_alloc_writecombine(pcm->card->dev, size,
392 &buf->addr, GFP_KERNEL);
399 static void s3c24xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
401 struct snd_pcm_substream *substream;
402 struct snd_dma_buffer *buf;
405 pr_debug("Entered %s\n", __func__);
407 for (stream = 0; stream < 2; stream++) {
408 substream = pcm->streams[stream].substream;
412 buf = &substream->dma_buffer;
416 dma_free_writecombine(pcm->card->dev, buf->bytes,
417 buf->area, buf->addr);
422 static u64 s3c24xx_pcm_dmamask = DMA_BIT_MASK(32);
424 static int s3c24xx_pcm_new(struct snd_card *card,
425 struct snd_soc_dai *dai, struct snd_pcm *pcm)
429 pr_debug("Entered %s\n", __func__);
431 if (!card->dev->dma_mask)
432 card->dev->dma_mask = &s3c24xx_pcm_dmamask;
433 if (!card->dev->coherent_dma_mask)
434 card->dev->coherent_dma_mask = 0xffffffff;
436 if (dai->playback.channels_min) {
437 ret = s3c24xx_pcm_preallocate_dma_buffer(pcm,
438 SNDRV_PCM_STREAM_PLAYBACK);
443 if (dai->capture.channels_min) {
444 ret = s3c24xx_pcm_preallocate_dma_buffer(pcm,
445 SNDRV_PCM_STREAM_CAPTURE);
453 struct snd_soc_platform s3c24xx_soc_platform = {
454 .name = "s3c24xx-audio",
455 .pcm_ops = &s3c24xx_pcm_ops,
456 .pcm_new = s3c24xx_pcm_new,
457 .pcm_free = s3c24xx_pcm_free_dma_buffers,
459 EXPORT_SYMBOL_GPL(s3c24xx_soc_platform);
461 static int __init s3c24xx_soc_platform_init(void)
463 return snd_soc_register_platform(&s3c24xx_soc_platform);
465 module_init(s3c24xx_soc_platform_init);
467 static void __exit s3c24xx_soc_platform_exit(void)
469 snd_soc_unregister_platform(&s3c24xx_soc_platform);
471 module_exit(s3c24xx_soc_platform_exit);
473 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
474 MODULE_DESCRIPTION("Samsung S3C24XX PCM DMA module");
475 MODULE_LICENSE("GPL");