2 * omap-pcm.c -- ALSA PCM interface for the OMAP SoC
4 * Copyright (C) 2008 Nokia Corporation
6 * Contact: Jarkko Nikula <jhnikula@gmail.com>
7 * Peter Ujfalusi <peter.ujfalusi@nokia.com>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * version 2 as published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
25 #include <linux/dma-mapping.h>
26 #include <sound/core.h>
27 #include <sound/pcm.h>
28 #include <sound/pcm_params.h>
29 #include <sound/soc.h>
34 static const struct snd_pcm_hardware omap_pcm_hardware = {
35 .info = SNDRV_PCM_INFO_MMAP |
36 SNDRV_PCM_INFO_MMAP_VALID |
37 SNDRV_PCM_INFO_INTERLEAVED |
38 SNDRV_PCM_INFO_PAUSE |
39 SNDRV_PCM_INFO_RESUME,
40 .formats = SNDRV_PCM_FMTBIT_S16_LE |
41 SNDRV_PCM_FMTBIT_S32_LE,
42 .period_bytes_min = 32,
43 .period_bytes_max = 64 * 1024,
46 .buffer_bytes_max = 128 * 1024,
49 struct omap_runtime_data {
51 struct omap_pcm_dma_data *dma_data;
56 static void omap_pcm_dma_irq(int ch, u16 stat, void *data)
58 struct snd_pcm_substream *substream = data;
59 struct snd_pcm_runtime *runtime = substream->runtime;
60 struct omap_runtime_data *prtd = runtime->private_data;
63 if ((cpu_is_omap1510()) &&
64 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)) {
66 * OMAP1510 doesn't fully support DMA progress counter
67 * and there is no software emulation implemented yet,
68 * so have to maintain our own playback progress counter
69 * that can be used by omap_pcm_pointer() instead.
71 spin_lock_irqsave(&prtd->lock, flags);
72 if ((stat == OMAP_DMA_LAST_IRQ) &&
73 (prtd->period_index == runtime->periods - 1)) {
74 /* we are in sync, do nothing */
75 spin_unlock_irqrestore(&prtd->lock, flags);
78 if (prtd->period_index >= 0) {
79 if (stat & OMAP_DMA_BLOCK_IRQ) {
80 /* end of buffer reached, loop back */
81 prtd->period_index = 0;
82 } else if (stat & OMAP_DMA_LAST_IRQ) {
83 /* update the counter for the last period */
84 prtd->period_index = runtime->periods - 1;
85 } else if (++prtd->period_index >= runtime->periods) {
86 /* end of buffer missed? loop back */
87 prtd->period_index = 0;
90 spin_unlock_irqrestore(&prtd->lock, flags);
93 snd_pcm_period_elapsed(substream);
96 /* this may get called several times by oss emulation */
97 static int omap_pcm_hw_params(struct snd_pcm_substream *substream,
98 struct snd_pcm_hw_params *params)
100 struct snd_pcm_runtime *runtime = substream->runtime;
101 struct snd_soc_pcm_runtime *rtd = substream->private_data;
102 struct omap_runtime_data *prtd = runtime->private_data;
103 struct omap_pcm_dma_data *dma_data = rtd->dai->cpu_dai->dma_data;
106 /* return if this is a bufferless transfer e.g.
107 * codec <--> BT codec or GSM modem -- lg FIXME */
111 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
112 runtime->dma_bytes = params_buffer_bytes(params);
116 prtd->dma_data = dma_data;
117 err = omap_request_dma(dma_data->dma_req, dma_data->name,
118 omap_pcm_dma_irq, substream, &prtd->dma_ch);
121 * Link channel with itself so DMA doesn't need any
122 * reprogramming while looping the buffer
124 omap_dma_link_lch(prtd->dma_ch, prtd->dma_ch);
130 static int omap_pcm_hw_free(struct snd_pcm_substream *substream)
132 struct snd_pcm_runtime *runtime = substream->runtime;
133 struct omap_runtime_data *prtd = runtime->private_data;
135 if (prtd->dma_data == NULL)
138 omap_dma_unlink_lch(prtd->dma_ch, prtd->dma_ch);
139 omap_free_dma(prtd->dma_ch);
140 prtd->dma_data = NULL;
142 snd_pcm_set_runtime_buffer(substream, NULL);
147 static int omap_pcm_prepare(struct snd_pcm_substream *substream)
149 struct snd_pcm_runtime *runtime = substream->runtime;
150 struct omap_runtime_data *prtd = runtime->private_data;
151 struct omap_pcm_dma_data *dma_data = prtd->dma_data;
152 struct omap_dma_channel_params dma_params;
155 /* return if this is a bufferless transfer e.g.
156 * codec <--> BT codec or GSM modem -- lg FIXME */
160 memset(&dma_params, 0, sizeof(dma_params));
161 dma_params.data_type = dma_data->data_type;
162 dma_params.trigger = dma_data->dma_req;
163 dma_params.sync_mode = dma_data->sync_mode;
164 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
165 dma_params.src_amode = OMAP_DMA_AMODE_POST_INC;
166 dma_params.dst_amode = OMAP_DMA_AMODE_CONSTANT;
167 dma_params.src_or_dst_synch = OMAP_DMA_DST_SYNC;
168 dma_params.src_start = runtime->dma_addr;
169 dma_params.dst_start = dma_data->port_addr;
170 dma_params.dst_port = OMAP_DMA_PORT_MPUI;
171 dma_params.dst_fi = dma_data->packet_size;
173 dma_params.src_amode = OMAP_DMA_AMODE_CONSTANT;
174 dma_params.dst_amode = OMAP_DMA_AMODE_POST_INC;
175 dma_params.src_or_dst_synch = OMAP_DMA_SRC_SYNC;
176 dma_params.src_start = dma_data->port_addr;
177 dma_params.dst_start = runtime->dma_addr;
178 dma_params.src_port = OMAP_DMA_PORT_MPUI;
179 dma_params.src_fi = dma_data->packet_size;
182 * Set DMA transfer frame size equal to ALSA period size and frame
183 * count as no. of ALSA periods. Then with DMA frame interrupt enabled,
184 * we can transfer the whole ALSA buffer with single DMA transfer but
185 * still can get an interrupt at each period bounary
187 bytes = snd_pcm_lib_period_bytes(substream);
188 dma_params.elem_count = bytes >> dma_data->data_type;
189 dma_params.frame_count = runtime->periods;
190 omap_set_dma_params(prtd->dma_ch, &dma_params);
192 if ((cpu_is_omap1510()) &&
193 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK))
194 omap_enable_dma_irq(prtd->dma_ch, OMAP_DMA_FRAME_IRQ |
195 OMAP_DMA_LAST_IRQ | OMAP_DMA_BLOCK_IRQ);
197 omap_enable_dma_irq(prtd->dma_ch, OMAP_DMA_FRAME_IRQ);
199 if (!(cpu_class_is_omap1())) {
200 omap_set_dma_src_burst_mode(prtd->dma_ch,
201 OMAP_DMA_DATA_BURST_16);
202 omap_set_dma_dest_burst_mode(prtd->dma_ch,
203 OMAP_DMA_DATA_BURST_16);
209 static int omap_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
211 struct snd_pcm_runtime *runtime = substream->runtime;
212 struct omap_runtime_data *prtd = runtime->private_data;
213 struct omap_pcm_dma_data *dma_data = prtd->dma_data;
217 spin_lock_irqsave(&prtd->lock, flags);
219 case SNDRV_PCM_TRIGGER_START:
220 case SNDRV_PCM_TRIGGER_RESUME:
221 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
222 prtd->period_index = 0;
223 /* Configure McBSP internal buffer usage */
224 if (dma_data->set_threshold)
225 dma_data->set_threshold(substream);
227 omap_start_dma(prtd->dma_ch);
230 case SNDRV_PCM_TRIGGER_STOP:
231 case SNDRV_PCM_TRIGGER_SUSPEND:
232 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
233 prtd->period_index = -1;
234 omap_stop_dma(prtd->dma_ch);
239 spin_unlock_irqrestore(&prtd->lock, flags);
244 static snd_pcm_uframes_t omap_pcm_pointer(struct snd_pcm_substream *substream)
246 struct snd_pcm_runtime *runtime = substream->runtime;
247 struct omap_runtime_data *prtd = runtime->private_data;
249 snd_pcm_uframes_t offset;
251 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
252 ptr = omap_get_dma_dst_pos(prtd->dma_ch);
253 offset = bytes_to_frames(runtime, ptr - runtime->dma_addr);
254 } else if (!(cpu_is_omap1510())) {
255 ptr = omap_get_dma_src_pos(prtd->dma_ch);
256 offset = bytes_to_frames(runtime, ptr - runtime->dma_addr);
258 offset = prtd->period_index * runtime->period_size;
260 if (offset >= runtime->buffer_size)
266 static int omap_pcm_open(struct snd_pcm_substream *substream)
268 struct snd_pcm_runtime *runtime = substream->runtime;
269 struct omap_runtime_data *prtd;
272 snd_soc_set_runtime_hwparams(substream, &omap_pcm_hardware);
274 /* Ensure that buffer size is a multiple of period size */
275 ret = snd_pcm_hw_constraint_integer(runtime,
276 SNDRV_PCM_HW_PARAM_PERIODS);
280 prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
285 spin_lock_init(&prtd->lock);
286 runtime->private_data = prtd;
292 static int omap_pcm_close(struct snd_pcm_substream *substream)
294 struct snd_pcm_runtime *runtime = substream->runtime;
296 kfree(runtime->private_data);
300 static int omap_pcm_mmap(struct snd_pcm_substream *substream,
301 struct vm_area_struct *vma)
303 struct snd_pcm_runtime *runtime = substream->runtime;
305 return dma_mmap_writecombine(substream->pcm->card->dev, vma,
311 static struct snd_pcm_ops omap_pcm_ops = {
312 .open = omap_pcm_open,
313 .close = omap_pcm_close,
314 .ioctl = snd_pcm_lib_ioctl,
315 .hw_params = omap_pcm_hw_params,
316 .hw_free = omap_pcm_hw_free,
317 .prepare = omap_pcm_prepare,
318 .trigger = omap_pcm_trigger,
319 .pointer = omap_pcm_pointer,
320 .mmap = omap_pcm_mmap,
323 static u64 omap_pcm_dmamask = DMA_BIT_MASK(64);
325 static int omap_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
328 struct snd_pcm_substream *substream = pcm->streams[stream].substream;
329 struct snd_dma_buffer *buf = &substream->dma_buffer;
330 size_t size = omap_pcm_hardware.buffer_bytes_max;
332 buf->dev.type = SNDRV_DMA_TYPE_DEV;
333 buf->dev.dev = pcm->card->dev;
334 buf->private_data = NULL;
335 buf->area = dma_alloc_writecombine(pcm->card->dev, size,
336 &buf->addr, GFP_KERNEL);
344 static void omap_pcm_free_dma_buffers(struct snd_pcm *pcm)
346 struct snd_pcm_substream *substream;
347 struct snd_dma_buffer *buf;
350 for (stream = 0; stream < 2; stream++) {
351 substream = pcm->streams[stream].substream;
355 buf = &substream->dma_buffer;
359 dma_free_writecombine(pcm->card->dev, buf->bytes,
360 buf->area, buf->addr);
365 static int omap_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
370 if (!card->dev->dma_mask)
371 card->dev->dma_mask = &omap_pcm_dmamask;
372 if (!card->dev->coherent_dma_mask)
373 card->dev->coherent_dma_mask = DMA_BIT_MASK(64);
375 if (dai->playback.channels_min) {
376 ret = omap_pcm_preallocate_dma_buffer(pcm,
377 SNDRV_PCM_STREAM_PLAYBACK);
382 if (dai->capture.channels_min) {
383 ret = omap_pcm_preallocate_dma_buffer(pcm,
384 SNDRV_PCM_STREAM_CAPTURE);
393 struct snd_soc_platform omap_soc_platform = {
394 .name = "omap-pcm-audio",
395 .pcm_ops = &omap_pcm_ops,
396 .pcm_new = omap_pcm_new,
397 .pcm_free = omap_pcm_free_dma_buffers,
399 EXPORT_SYMBOL_GPL(omap_soc_platform);
401 static int __init omap_soc_platform_init(void)
403 return snd_soc_register_platform(&omap_soc_platform);
405 module_init(omap_soc_platform_init);
407 static void __exit omap_soc_platform_exit(void)
409 snd_soc_unregister_platform(&omap_soc_platform);
411 module_exit(omap_soc_platform_exit);
413 MODULE_AUTHOR("Jarkko Nikula <jhnikula@gmail.com>");
414 MODULE_DESCRIPTION("OMAP PCM DMA module");
415 MODULE_LICENSE("GPL");