2 * dma.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/slab.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/module.h>
21 #include <sound/soc.h>
22 #include <sound/pcm_params.h>
25 #include <mach/hardware.h>
30 #define ST_RUNNING (1<<0)
31 #define ST_OPENED (1<<1)
33 static const struct snd_pcm_hardware dma_hardware = {
34 .info = SNDRV_PCM_INFO_INTERLEAVED |
35 SNDRV_PCM_INFO_BLOCK_TRANSFER |
37 SNDRV_PCM_INFO_MMAP_VALID,
38 .formats = SNDRV_PCM_FMTBIT_S16_LE |
39 SNDRV_PCM_FMTBIT_U16_LE |
44 .buffer_bytes_max = 128*1024,
45 .period_bytes_min = PAGE_SIZE,
46 .period_bytes_max = PAGE_SIZE*2,
55 unsigned int dma_loaded;
56 unsigned int dma_period;
60 struct s3c_dma_params *params;
63 static void audio_buffdone(void *data);
67 * place a dma buffer onto the queue for the dma system
70 static void dma_enqueue(struct snd_pcm_substream *substream)
72 struct runtime_data *prtd = substream->runtime->private_data;
73 dma_addr_t pos = prtd->dma_pos;
75 struct samsung_dma_prep dma_info;
77 pr_debug("Entered %s\n", __func__);
79 limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
81 pr_debug("%s: loaded %d, limit %d\n",
82 __func__, prtd->dma_loaded, limit);
84 dma_info.cap = (samsung_dma_has_circular() ? DMA_CYCLIC : DMA_SLAVE);
86 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
87 ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
88 dma_info.fp = audio_buffdone;
89 dma_info.fp_param = substream;
90 dma_info.period = prtd->dma_period;
91 dma_info.len = prtd->dma_period*limit;
93 while (prtd->dma_loaded < limit) {
94 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
96 if ((pos + dma_info.period) > prtd->dma_end) {
97 dma_info.period = prtd->dma_end - pos;
98 pr_debug("%s: corrected dma len %ld\n",
99 __func__, dma_info.period);
103 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
106 pos += prtd->dma_period;
107 if (pos >= prtd->dma_end)
108 pos = prtd->dma_start;
114 static void audio_buffdone(void *data)
116 struct snd_pcm_substream *substream = data;
117 struct runtime_data *prtd = substream->runtime->private_data;
119 pr_debug("Entered %s\n", __func__);
121 if (prtd->state & ST_RUNNING) {
122 prtd->dma_pos += prtd->dma_period;
123 if (prtd->dma_pos >= prtd->dma_end)
124 prtd->dma_pos = prtd->dma_start;
127 snd_pcm_period_elapsed(substream);
129 spin_lock(&prtd->lock);
130 if (!samsung_dma_has_circular()) {
132 dma_enqueue(substream);
134 spin_unlock(&prtd->lock);
138 static int dma_hw_params(struct snd_pcm_substream *substream,
139 struct snd_pcm_hw_params *params)
141 struct snd_pcm_runtime *runtime = substream->runtime;
142 struct runtime_data *prtd = runtime->private_data;
143 struct snd_soc_pcm_runtime *rtd = substream->private_data;
144 unsigned long totbytes = params_buffer_bytes(params);
145 struct s3c_dma_params *dma =
146 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
147 struct samsung_dma_req req;
148 struct samsung_dma_config config;
150 pr_debug("Entered %s\n", __func__);
152 /* return if this is a bufferless transfer e.g.
153 * codec <--> BT codec or GSM modem -- lg FIXME */
157 /* this may get called several times by oss emulation
158 * with different params -HW */
159 if (prtd->params == NULL) {
163 pr_debug("params %p, client %p, channel %d\n", prtd->params,
164 prtd->params->client, prtd->params->channel);
166 prtd->params->ops = samsung_dma_get_ops();
168 req.cap = (samsung_dma_has_circular() ?
169 DMA_CYCLIC : DMA_SLAVE);
170 req.client = prtd->params->client;
172 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
173 ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
174 config.width = prtd->params->dma_size;
175 config.fifo = prtd->params->dma_addr;
176 prtd->params->ch = prtd->params->ops->request(
177 prtd->params->channel, &req);
178 prtd->params->ops->config(prtd->params->ch, &config);
181 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
183 runtime->dma_bytes = totbytes;
185 spin_lock_irq(&prtd->lock);
186 prtd->dma_loaded = 0;
187 prtd->dma_period = params_period_bytes(params);
188 prtd->dma_start = runtime->dma_addr;
189 prtd->dma_pos = prtd->dma_start;
190 prtd->dma_end = prtd->dma_start + totbytes;
191 spin_unlock_irq(&prtd->lock);
196 static int dma_hw_free(struct snd_pcm_substream *substream)
198 struct runtime_data *prtd = substream->runtime->private_data;
200 pr_debug("Entered %s\n", __func__);
202 snd_pcm_set_runtime_buffer(substream, NULL);
205 prtd->params->ops->flush(prtd->params->ch);
206 prtd->params->ops->release(prtd->params->ch,
207 prtd->params->client);
214 static int dma_prepare(struct snd_pcm_substream *substream)
216 struct runtime_data *prtd = substream->runtime->private_data;
219 pr_debug("Entered %s\n", __func__);
221 /* return if this is a bufferless transfer e.g.
222 * codec <--> BT codec or GSM modem -- lg FIXME */
226 /* flush the DMA channel */
227 prtd->params->ops->flush(prtd->params->ch);
229 prtd->dma_loaded = 0;
230 prtd->dma_pos = prtd->dma_start;
232 /* enqueue dma buffers */
233 dma_enqueue(substream);
238 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
240 struct runtime_data *prtd = substream->runtime->private_data;
243 pr_debug("Entered %s\n", __func__);
245 spin_lock(&prtd->lock);
248 case SNDRV_PCM_TRIGGER_START:
249 prtd->state |= ST_RUNNING;
250 prtd->params->ops->trigger(prtd->params->ch);
253 case SNDRV_PCM_TRIGGER_STOP:
254 prtd->state &= ~ST_RUNNING;
255 prtd->params->ops->stop(prtd->params->ch);
263 spin_unlock(&prtd->lock);
268 static snd_pcm_uframes_t
269 dma_pointer(struct snd_pcm_substream *substream)
271 struct snd_pcm_runtime *runtime = substream->runtime;
272 struct runtime_data *prtd = runtime->private_data;
275 pr_debug("Entered %s\n", __func__);
277 res = prtd->dma_pos - prtd->dma_start;
279 pr_debug("Pointer offset: %lu\n", res);
281 /* we seem to be getting the odd error from the pcm library due
282 * to out-of-bounds pointers. this is maybe due to the dma engine
283 * not having loaded the new values for the channel before being
284 * called... (todo - fix )
287 if (res >= snd_pcm_lib_buffer_bytes(substream)) {
288 if (res == snd_pcm_lib_buffer_bytes(substream))
292 return bytes_to_frames(substream->runtime, res);
295 static int dma_open(struct snd_pcm_substream *substream)
297 struct snd_pcm_runtime *runtime = substream->runtime;
298 struct runtime_data *prtd;
300 pr_debug("Entered %s\n", __func__);
302 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
303 snd_soc_set_runtime_hwparams(substream, &dma_hardware);
305 prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
309 spin_lock_init(&prtd->lock);
311 runtime->private_data = prtd;
315 static int dma_close(struct snd_pcm_substream *substream)
317 struct snd_pcm_runtime *runtime = substream->runtime;
318 struct runtime_data *prtd = runtime->private_data;
320 pr_debug("Entered %s\n", __func__);
323 pr_debug("dma_close called with prtd == NULL\n");
330 static int dma_mmap(struct snd_pcm_substream *substream,
331 struct vm_area_struct *vma)
333 struct snd_pcm_runtime *runtime = substream->runtime;
335 pr_debug("Entered %s\n", __func__);
337 return dma_mmap_writecombine(substream->pcm->card->dev, vma,
343 static struct snd_pcm_ops dma_ops = {
346 .ioctl = snd_pcm_lib_ioctl,
347 .hw_params = dma_hw_params,
348 .hw_free = dma_hw_free,
349 .prepare = dma_prepare,
350 .trigger = dma_trigger,
351 .pointer = dma_pointer,
355 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
357 struct snd_pcm_substream *substream = pcm->streams[stream].substream;
358 struct snd_dma_buffer *buf = &substream->dma_buffer;
359 size_t size = dma_hardware.buffer_bytes_max;
361 pr_debug("Entered %s\n", __func__);
363 buf->dev.type = SNDRV_DMA_TYPE_DEV;
364 buf->dev.dev = pcm->card->dev;
365 buf->private_data = NULL;
366 buf->area = dma_alloc_writecombine(pcm->card->dev, size,
367 &buf->addr, GFP_KERNEL);
374 static void dma_free_dma_buffers(struct snd_pcm *pcm)
376 struct snd_pcm_substream *substream;
377 struct snd_dma_buffer *buf;
380 pr_debug("Entered %s\n", __func__);
382 for (stream = 0; stream < 2; stream++) {
383 substream = pcm->streams[stream].substream;
387 buf = &substream->dma_buffer;
391 dma_free_writecombine(pcm->card->dev, buf->bytes,
392 buf->area, buf->addr);
397 static u64 dma_mask = DMA_BIT_MASK(32);
399 static int dma_new(struct snd_soc_pcm_runtime *rtd)
401 struct snd_card *card = rtd->card->snd_card;
402 struct snd_pcm *pcm = rtd->pcm;
405 pr_debug("Entered %s\n", __func__);
407 if (!card->dev->dma_mask)
408 card->dev->dma_mask = &dma_mask;
409 if (!card->dev->coherent_dma_mask)
410 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
412 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
413 ret = preallocate_dma_buffer(pcm,
414 SNDRV_PCM_STREAM_PLAYBACK);
419 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
420 ret = preallocate_dma_buffer(pcm,
421 SNDRV_PCM_STREAM_CAPTURE);
429 static struct snd_soc_platform_driver samsung_asoc_platform = {
432 .pcm_free = dma_free_dma_buffers,
435 static int __devinit samsung_asoc_platform_probe(struct platform_device *pdev)
437 return snd_soc_register_platform(&pdev->dev, &samsung_asoc_platform);
440 static int __devexit samsung_asoc_platform_remove(struct platform_device *pdev)
442 snd_soc_unregister_platform(&pdev->dev);
446 static struct platform_driver asoc_dma_driver = {
448 .name = "samsung-audio",
449 .owner = THIS_MODULE,
452 .probe = samsung_asoc_platform_probe,
453 .remove = __devexit_p(samsung_asoc_platform_remove),
456 module_platform_driver(asoc_dma_driver);
458 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
459 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
460 MODULE_LICENSE("GPL");
461 MODULE_ALIAS("platform:samsung-audio");