2 * Copyright (C) 2013, Analog Devices Inc.
3 * Author: Lars-Peter Clausen <lars@metafoo.de>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
10 * You should have received a copy of the GNU General Public License along
11 * with this program; if not, write to the Free Software Foundation, Inc.,
12 * 675 Mass Ave, Cambridge, MA 02139, USA.
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/dmaengine.h>
18 #include <linux/slab.h>
19 #include <sound/pcm.h>
20 #include <sound/pcm_params.h>
21 #include <sound/soc.h>
22 #include <linux/dma-mapping.h>
25 #include <sound/dmaengine_pcm.h>
27 struct dmaengine_pcm {
28 struct dma_chan *chan[SNDRV_PCM_STREAM_CAPTURE + 1];
29 const struct snd_dmaengine_pcm_config *config;
30 struct snd_soc_platform platform;
34 static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p)
36 return container_of(p, struct dmaengine_pcm, platform);
40 * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
41 * @substream: PCM substream
43 * @slave_config: DMA slave config to prepare
45 * This function can be used as a generic prepare_slave_config callback for
46 * platforms which make use of the snd_dmaengine_dai_dma_data struct for their
47 * DAI DMA data. Internally the function will first call
48 * snd_hwparams_to_dma_slave_config to fill in the slave config based on the
49 * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the
50 * remaining fields based on the DAI DMA data.
52 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
53 struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
55 struct snd_soc_pcm_runtime *rtd = substream->private_data;
56 struct snd_dmaengine_dai_dma_data *dma_data;
59 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
61 ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
65 snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
70 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
72 static int dmaengine_pcm_hw_params(struct snd_pcm_substream *substream,
73 struct snd_pcm_hw_params *params)
75 struct snd_soc_pcm_runtime *rtd = substream->private_data;
76 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
77 struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
78 struct dma_slave_config slave_config;
81 if (pcm->config->prepare_slave_config) {
82 ret = pcm->config->prepare_slave_config(substream, params,
87 ret = dmaengine_slave_config(chan, &slave_config);
92 return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
95 static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
97 struct snd_soc_pcm_runtime *rtd = substream->private_data;
98 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
99 struct dma_chan *chan = pcm->chan[substream->stream];
102 ret = snd_soc_set_runtime_hwparams(substream,
103 pcm->config->pcm_hardware);
107 return snd_dmaengine_pcm_open(substream, chan);
110 static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
111 struct snd_pcm_substream *substream)
113 if (!pcm->chan[substream->stream])
116 return pcm->chan[substream->stream]->device->dev;
119 static void dmaengine_pcm_free(struct snd_pcm *pcm)
121 snd_pcm_lib_preallocate_free_for_all(pcm);
124 static const char * const dmaengine_pcm_dma_channel_names[] = {
125 [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
126 [SNDRV_PCM_STREAM_CAPTURE] = "rx",
129 static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
131 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
132 const struct snd_dmaengine_pcm_config *config = pcm->config;
133 struct snd_pcm_substream *substream;
137 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
138 substream = rtd->pcm->streams[i].substream;
142 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
143 pcm->chan[i] = dma_request_slave_channel(rtd->platform->dev,
144 dmaengine_pcm_dma_channel_names[i]);
148 dev_err(rtd->platform->dev,
149 "Missing dma channel for stream: %d\n", i);
154 ret = snd_pcm_lib_preallocate_pages(substream,
156 dmaengine_dma_dev(pcm, substream),
157 config->prealloc_buffer_size,
158 config->pcm_hardware->buffer_bytes_max);
166 dmaengine_pcm_free(rtd->pcm);
170 static const struct snd_pcm_ops dmaengine_pcm_ops = {
171 .open = dmaengine_pcm_open,
172 .close = snd_dmaengine_pcm_close,
173 .ioctl = snd_pcm_lib_ioctl,
174 .hw_params = dmaengine_pcm_hw_params,
175 .hw_free = snd_pcm_lib_free_pages,
176 .trigger = snd_dmaengine_pcm_trigger,
177 .pointer = snd_dmaengine_pcm_pointer,
180 static const struct snd_soc_platform_driver dmaengine_pcm_platform = {
181 .ops = &dmaengine_pcm_ops,
182 .pcm_new = dmaengine_pcm_new,
183 .pcm_free = dmaengine_pcm_free,
184 .probe_order = SND_SOC_COMP_ORDER_LATE,
187 static const struct snd_pcm_ops dmaengine_no_residue_pcm_ops = {
188 .open = dmaengine_pcm_open,
189 .close = snd_dmaengine_pcm_close,
190 .ioctl = snd_pcm_lib_ioctl,
191 .hw_params = dmaengine_pcm_hw_params,
192 .hw_free = snd_pcm_lib_free_pages,
193 .trigger = snd_dmaengine_pcm_trigger,
194 .pointer = snd_dmaengine_pcm_pointer_no_residue,
197 static const struct snd_soc_platform_driver dmaengine_no_residue_pcm_platform = {
198 .ops = &dmaengine_no_residue_pcm_ops,
199 .pcm_new = dmaengine_pcm_new,
200 .pcm_free = dmaengine_pcm_free,
201 .probe_order = SND_SOC_COMP_ORDER_LATE,
204 static void dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
209 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || !dev->of_node)
212 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) {
213 pcm->chan[0] = dma_request_slave_channel(dev, "rx-tx");
214 pcm->chan[1] = pcm->chan[0];
216 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
217 pcm->chan[i] = dma_request_slave_channel(dev,
218 dmaengine_pcm_dma_channel_names[i]);
224 * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
225 * @dev: The parent device for the PCM device
226 * @config: Platform specific PCM configuration
227 * @flags: Platform specific quirks
229 int snd_dmaengine_pcm_register(struct device *dev,
230 const struct snd_dmaengine_pcm_config *config, unsigned int flags)
232 struct dmaengine_pcm *pcm;
234 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
238 pcm->config = config;
241 dmaengine_pcm_request_chan_of(pcm, dev);
243 if (flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
244 return snd_soc_add_platform(dev, &pcm->platform,
245 &dmaengine_no_residue_pcm_platform);
247 return snd_soc_add_platform(dev, &pcm->platform,
248 &dmaengine_pcm_platform);
250 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
253 * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
254 * @dev: Parent device the PCM was register with
256 * Removes a dmaengine based PCM device previously registered with
257 * snd_dmaengine_pcm_register.
259 void snd_dmaengine_pcm_unregister(struct device *dev)
261 struct snd_soc_platform *platform;
262 struct dmaengine_pcm *pcm;
265 platform = snd_soc_lookup_platform(dev);
269 pcm = soc_platform_to_pcm(platform);
271 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
273 dma_release_channel(pcm->chan[i]);
274 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
279 snd_soc_remove_platform(platform);
282 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
284 MODULE_LICENSE("GPL");