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>
24 #include <linux/of_dma.h>
26 #include <sound/dmaengine_pcm.h>
28 struct dmaengine_pcm {
29 struct dma_chan *chan[SNDRV_PCM_STREAM_CAPTURE + 1];
30 const struct snd_dmaengine_pcm_config *config;
31 struct snd_soc_platform platform;
35 static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p)
37 return container_of(p, struct dmaengine_pcm, platform);
41 * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
42 * @substream: PCM substream
44 * @slave_config: DMA slave config to prepare
46 * This function can be used as a generic prepare_slave_config callback for
47 * platforms which make use of the snd_dmaengine_dai_dma_data struct for their
48 * DAI DMA data. Internally the function will first call
49 * snd_hwparams_to_dma_slave_config to fill in the slave config based on the
50 * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the
51 * remaining fields based on the DAI DMA data.
53 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
54 struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
56 struct snd_soc_pcm_runtime *rtd = substream->private_data;
57 struct snd_dmaengine_dai_dma_data *dma_data;
60 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
62 ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
66 snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
71 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
73 static int dmaengine_pcm_hw_params(struct snd_pcm_substream *substream,
74 struct snd_pcm_hw_params *params)
76 struct snd_soc_pcm_runtime *rtd = substream->private_data;
77 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
78 struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
79 struct dma_slave_config slave_config;
82 if (pcm->config->prepare_slave_config) {
83 ret = pcm->config->prepare_slave_config(substream, params,
88 ret = dmaengine_slave_config(chan, &slave_config);
93 return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
96 static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
98 struct snd_soc_pcm_runtime *rtd = substream->private_data;
99 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
100 struct dma_chan *chan = pcm->chan[substream->stream];
103 ret = snd_soc_set_runtime_hwparams(substream,
104 pcm->config->pcm_hardware);
108 return snd_dmaengine_pcm_open(substream, chan);
111 static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
112 struct snd_pcm_substream *substream)
114 if (!pcm->chan[substream->stream])
117 return pcm->chan[substream->stream]->device->dev;
120 static void dmaengine_pcm_free(struct snd_pcm *pcm)
122 snd_pcm_lib_preallocate_free_for_all(pcm);
125 static struct dma_chan *dmaengine_pcm_compat_request_channel(
126 struct snd_soc_pcm_runtime *rtd,
127 struct snd_pcm_substream *substream)
129 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
131 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0])
134 if (pcm->config->compat_request_channel)
135 return pcm->config->compat_request_channel(rtd, substream);
137 return snd_dmaengine_pcm_request_channel(pcm->config->compat_filter_fn,
138 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream));
141 static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
143 struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
144 const struct snd_dmaengine_pcm_config *config = pcm->config;
145 struct snd_pcm_substream *substream;
149 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
150 substream = rtd->pcm->streams[i].substream;
154 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
155 pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
160 dev_err(rtd->platform->dev,
161 "Missing dma channel for stream: %d\n", i);
166 ret = snd_pcm_lib_preallocate_pages(substream,
168 dmaengine_dma_dev(pcm, substream),
169 config->prealloc_buffer_size,
170 config->pcm_hardware->buffer_bytes_max);
178 dmaengine_pcm_free(rtd->pcm);
182 static const struct snd_pcm_ops dmaengine_pcm_ops = {
183 .open = dmaengine_pcm_open,
184 .close = snd_dmaengine_pcm_close,
185 .ioctl = snd_pcm_lib_ioctl,
186 .hw_params = dmaengine_pcm_hw_params,
187 .hw_free = snd_pcm_lib_free_pages,
188 .trigger = snd_dmaengine_pcm_trigger,
189 .pointer = snd_dmaengine_pcm_pointer,
192 static const struct snd_soc_platform_driver dmaengine_pcm_platform = {
193 .ops = &dmaengine_pcm_ops,
194 .pcm_new = dmaengine_pcm_new,
195 .pcm_free = dmaengine_pcm_free,
196 .probe_order = SND_SOC_COMP_ORDER_LATE,
199 static const struct snd_pcm_ops dmaengine_no_residue_pcm_ops = {
200 .open = dmaengine_pcm_open,
201 .close = snd_dmaengine_pcm_close,
202 .ioctl = snd_pcm_lib_ioctl,
203 .hw_params = dmaengine_pcm_hw_params,
204 .hw_free = snd_pcm_lib_free_pages,
205 .trigger = snd_dmaengine_pcm_trigger,
206 .pointer = snd_dmaengine_pcm_pointer_no_residue,
209 static const struct snd_soc_platform_driver dmaengine_no_residue_pcm_platform = {
210 .ops = &dmaengine_no_residue_pcm_ops,
211 .pcm_new = dmaengine_pcm_new,
212 .pcm_free = dmaengine_pcm_free,
213 .probe_order = SND_SOC_COMP_ORDER_LATE,
216 static const char * const dmaengine_pcm_dma_channel_names[] = {
217 [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
218 [SNDRV_PCM_STREAM_CAPTURE] = "rx",
221 static void dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
222 struct device_node *of_node)
226 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || !of_node)
229 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) {
230 pcm->chan[0] = of_dma_request_slave_channel(of_node, "tx_rx");
231 pcm->chan[1] = pcm->chan[0];
233 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
234 pcm->chan[i] = of_dma_request_slave_channel(of_node,
235 dmaengine_pcm_dma_channel_names[i]);
241 * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
242 * @dev: The parent device for the PCM device
243 * @config: Platform specific PCM configuration
244 * @flags: Platform specific quirks
246 int snd_dmaengine_pcm_register(struct device *dev,
247 const struct snd_dmaengine_pcm_config *config, unsigned int flags)
249 struct dmaengine_pcm *pcm;
251 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
255 pcm->config = config;
258 dmaengine_pcm_request_chan_of(pcm, dev->of_node);
260 if (flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
261 return snd_soc_add_platform(dev, &pcm->platform,
262 &dmaengine_no_residue_pcm_platform);
264 return snd_soc_add_platform(dev, &pcm->platform,
265 &dmaengine_pcm_platform);
267 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
270 * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
271 * @dev: Parent device the PCM was register with
273 * Removes a dmaengine based PCM device previously registered with
274 * snd_dmaengine_pcm_register.
276 void snd_dmaengine_pcm_unregister(struct device *dev)
278 struct snd_soc_platform *platform;
279 struct dmaengine_pcm *pcm;
282 platform = snd_soc_lookup_platform(dev);
286 pcm = soc_platform_to_pcm(platform);
288 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
290 dma_release_channel(pcm->chan[i]);
291 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
296 snd_soc_remove_platform(platform);
299 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
301 MODULE_LICENSE("GPL");