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28c4468b LPC |
1 | /* |
2 | * Copyright (C) 2013, Analog Devices Inc. | |
3 | * Author: Lars-Peter Clausen <lars@metafoo.de> | |
4 | * | |
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. | |
9 | * | |
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. | |
13 | * | |
14 | */ | |
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> | |
23 | #include <linux/of.h> | |
28c4468b LPC |
24 | |
25 | #include <sound/dmaengine_pcm.h> | |
26 | ||
acde50a7 LPC |
27 | /* |
28 | * The platforms dmaengine driver does not support reporting the amount of | |
29 | * bytes that are still left to transfer. | |
30 | */ | |
31 | #define SND_DMAENGINE_PCM_FLAG_NO_RESIDUE BIT(31) | |
32 | ||
28c4468b | 33 | struct dmaengine_pcm { |
f82bf8e2 | 34 | struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1]; |
28c4468b LPC |
35 | const struct snd_dmaengine_pcm_config *config; |
36 | struct snd_soc_platform platform; | |
d1e1406c | 37 | unsigned int flags; |
28c4468b LPC |
38 | }; |
39 | ||
40 | static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p) | |
41 | { | |
42 | return container_of(p, struct dmaengine_pcm, platform); | |
43 | } | |
44 | ||
c0de42bf LPC |
45 | static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm, |
46 | struct snd_pcm_substream *substream) | |
47 | { | |
48 | if (!pcm->chan[substream->stream]) | |
49 | return NULL; | |
50 | ||
51 | return pcm->chan[substream->stream]->device->dev; | |
52 | } | |
53 | ||
28c4468b LPC |
54 | /** |
55 | * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback | |
56 | * @substream: PCM substream | |
57 | * @params: hw_params | |
58 | * @slave_config: DMA slave config to prepare | |
59 | * | |
60 | * This function can be used as a generic prepare_slave_config callback for | |
61 | * platforms which make use of the snd_dmaengine_dai_dma_data struct for their | |
62 | * DAI DMA data. Internally the function will first call | |
63 | * snd_hwparams_to_dma_slave_config to fill in the slave config based on the | |
64 | * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the | |
65 | * remaining fields based on the DAI DMA data. | |
66 | */ | |
67 | int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream, | |
68 | struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config) | |
69 | { | |
70 | struct snd_soc_pcm_runtime *rtd = substream->private_data; | |
71 | struct snd_dmaengine_dai_dma_data *dma_data; | |
72 | int ret; | |
73 | ||
74 | dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); | |
75 | ||
76 | ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config); | |
77 | if (ret) | |
78 | return ret; | |
79 | ||
80 | snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data, | |
81 | slave_config); | |
82 | ||
83 | return 0; | |
84 | } | |
85 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config); | |
86 | ||
87 | static int dmaengine_pcm_hw_params(struct snd_pcm_substream *substream, | |
88 | struct snd_pcm_hw_params *params) | |
89 | { | |
90 | struct snd_soc_pcm_runtime *rtd = substream->private_data; | |
91 | struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); | |
92 | struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream); | |
fa654e08 LPC |
93 | int (*prepare_slave_config)(struct snd_pcm_substream *substream, |
94 | struct snd_pcm_hw_params *params, | |
95 | struct dma_slave_config *slave_config); | |
28c4468b LPC |
96 | struct dma_slave_config slave_config; |
97 | int ret; | |
98 | ||
a894bd7f LJ |
99 | memset(&slave_config, 0, sizeof(slave_config)); |
100 | ||
fa654e08 LPC |
101 | if (!pcm->config) |
102 | prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; | |
103 | else | |
104 | prepare_slave_config = pcm->config->prepare_slave_config; | |
105 | ||
106 | if (prepare_slave_config) { | |
107 | ret = prepare_slave_config(substream, params, &slave_config); | |
28c4468b LPC |
108 | if (ret) |
109 | return ret; | |
110 | ||
111 | ret = dmaengine_slave_config(chan, &slave_config); | |
112 | if (ret) | |
113 | return ret; | |
114 | } | |
115 | ||
116 | return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); | |
117 | } | |
118 | ||
c0de42bf | 119 | static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substream) |
28c4468b LPC |
120 | { |
121 | struct snd_soc_pcm_runtime *rtd = substream->private_data; | |
122 | struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); | |
c0de42bf | 123 | struct device *dma_dev = dmaengine_dma_dev(pcm, substream); |
28c4468b | 124 | struct dma_chan *chan = pcm->chan[substream->stream]; |
c0de42bf LPC |
125 | struct snd_dmaengine_dai_dma_data *dma_data; |
126 | struct dma_slave_caps dma_caps; | |
127 | struct snd_pcm_hardware hw; | |
2d38df12 PU |
128 | u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | |
129 | BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | | |
130 | BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); | |
131 | int i, ret; | |
28c4468b | 132 | |
fa654e08 | 133 | if (pcm->config && pcm->config->pcm_hardware) |
c0de42bf | 134 | return snd_soc_set_runtime_hwparams(substream, |
28c4468b | 135 | pcm->config->pcm_hardware); |
28c4468b | 136 | |
c0de42bf LPC |
137 | dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); |
138 | ||
139 | memset(&hw, 0, sizeof(hw)); | |
140 | hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | | |
141 | SNDRV_PCM_INFO_INTERLEAVED; | |
142 | hw.periods_min = 2; | |
143 | hw.periods_max = UINT_MAX; | |
144 | hw.period_bytes_min = 256; | |
145 | hw.period_bytes_max = dma_get_max_seg_size(dma_dev); | |
146 | hw.buffer_bytes_max = SIZE_MAX; | |
147 | hw.fifo_size = dma_data->fifo_size; | |
148 | ||
a22f33b0 LPC |
149 | if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE) |
150 | hw.info |= SNDRV_PCM_INFO_BATCH; | |
151 | ||
c0de42bf LPC |
152 | ret = dma_get_slave_caps(chan, &dma_caps); |
153 | if (ret == 0) { | |
154 | if (dma_caps.cmd_pause) | |
155 | hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME; | |
478028e0 LPC |
156 | if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT) |
157 | hw.info |= SNDRV_PCM_INFO_BATCH; | |
2d38df12 PU |
158 | |
159 | if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) | |
ceacbdbf | 160 | addr_widths = dma_caps.dst_addr_widths; |
2d38df12 PU |
161 | else |
162 | addr_widths = dma_caps.src_addr_widths; | |
163 | } | |
164 | ||
165 | /* | |
73fe01cf MR |
166 | * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep |
167 | * hw.formats set to 0, meaning no restrictions are in place. | |
168 | * In this case it's the responsibility of the DAI driver to | |
169 | * provide the supported format information. | |
2d38df12 | 170 | */ |
73fe01cf MR |
171 | if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)) |
172 | /* | |
173 | * Prepare formats mask for valid/allowed sample types. If the | |
174 | * dma does not have support for the given physical word size, | |
175 | * it needs to be masked out so user space can not use the | |
176 | * format which produces corrupted audio. | |
177 | * In case the dma driver does not implement the slave_caps the | |
178 | * default assumption is that it supports 1, 2 and 4 bytes | |
179 | * widths. | |
180 | */ | |
181 | for (i = 0; i <= SNDRV_PCM_FORMAT_LAST; i++) { | |
182 | int bits = snd_pcm_format_physical_width(i); | |
183 | ||
184 | /* | |
185 | * Enable only samples with DMA supported physical | |
186 | * widths | |
187 | */ | |
188 | switch (bits) { | |
189 | case 8: | |
190 | case 16: | |
191 | case 24: | |
192 | case 32: | |
193 | case 64: | |
194 | if (addr_widths & (1 << (bits / 8))) | |
195 | hw.formats |= (1LL << i); | |
196 | break; | |
197 | default: | |
198 | /* Unsupported types */ | |
199 | break; | |
200 | } | |
2d38df12 | 201 | } |
c0de42bf LPC |
202 | |
203 | return snd_soc_set_runtime_hwparams(substream, &hw); | |
28c4468b LPC |
204 | } |
205 | ||
c0de42bf | 206 | static int dmaengine_pcm_open(struct snd_pcm_substream *substream) |
28c4468b | 207 | { |
c0de42bf LPC |
208 | struct snd_soc_pcm_runtime *rtd = substream->private_data; |
209 | struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); | |
210 | struct dma_chan *chan = pcm->chan[substream->stream]; | |
211 | int ret; | |
28c4468b | 212 | |
c0de42bf LPC |
213 | ret = dmaengine_pcm_set_runtime_hwparams(substream); |
214 | if (ret) | |
215 | return ret; | |
216 | ||
217 | return snd_dmaengine_pcm_open(substream, chan); | |
28c4468b LPC |
218 | } |
219 | ||
c999836d LPC |
220 | static struct dma_chan *dmaengine_pcm_compat_request_channel( |
221 | struct snd_soc_pcm_runtime *rtd, | |
222 | struct snd_pcm_substream *substream) | |
223 | { | |
224 | struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); | |
90130d2e | 225 | struct snd_dmaengine_dai_dma_data *dma_data; |
ec4f2857 | 226 | dma_filter_fn fn = NULL; |
90130d2e MB |
227 | |
228 | dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); | |
c999836d | 229 | |
d1e1406c LPC |
230 | if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0]) |
231 | return pcm->chan[0]; | |
232 | ||
ec4f2857 | 233 | if (pcm->config && pcm->config->compat_request_channel) |
c999836d LPC |
234 | return pcm->config->compat_request_channel(rtd, substream); |
235 | ||
ec4f2857 XL |
236 | if (pcm->config) |
237 | fn = pcm->config->compat_filter_fn; | |
238 | ||
239 | return snd_dmaengine_pcm_request_channel(fn, dma_data->filter_data); | |
c999836d LPC |
240 | } |
241 | ||
acde50a7 LPC |
242 | static bool dmaengine_pcm_can_report_residue(struct device *dev, |
243 | struct dma_chan *chan) | |
478028e0 LPC |
244 | { |
245 | struct dma_slave_caps dma_caps; | |
246 | int ret; | |
247 | ||
248 | ret = dma_get_slave_caps(chan, &dma_caps); | |
acde50a7 LPC |
249 | if (ret != 0) { |
250 | dev_warn(dev, "Failed to get DMA channel capabilities, falling back to period counting: %d\n", | |
251 | ret); | |
252 | return false; | |
253 | } | |
478028e0 LPC |
254 | |
255 | if (dma_caps.residue_granularity == DMA_RESIDUE_GRANULARITY_DESCRIPTOR) | |
256 | return false; | |
257 | ||
258 | return true; | |
259 | } | |
260 | ||
28c4468b LPC |
261 | static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd) |
262 | { | |
263 | struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); | |
264 | const struct snd_dmaengine_pcm_config *config = pcm->config; | |
ea73b7dd MB |
265 | struct device *dev = rtd->platform->dev; |
266 | struct snd_dmaengine_dai_dma_data *dma_data; | |
28c4468b | 267 | struct snd_pcm_substream *substream; |
fa654e08 LPC |
268 | size_t prealloc_buffer_size; |
269 | size_t max_buffer_size; | |
28c4468b LPC |
270 | unsigned int i; |
271 | int ret; | |
272 | ||
fa654e08 LPC |
273 | if (config && config->prealloc_buffer_size) { |
274 | prealloc_buffer_size = config->prealloc_buffer_size; | |
275 | max_buffer_size = config->pcm_hardware->buffer_bytes_max; | |
276 | } else { | |
277 | prealloc_buffer_size = 512 * 1024; | |
278 | max_buffer_size = SIZE_MAX; | |
279 | } | |
280 | ||
281 | ||
28c4468b LPC |
282 | for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) { |
283 | substream = rtd->pcm->streams[i].substream; | |
284 | if (!substream) | |
285 | continue; | |
286 | ||
ea73b7dd MB |
287 | dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); |
288 | ||
289 | if (!pcm->chan[i] && | |
290 | (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) | |
291 | pcm->chan[i] = dma_request_slave_channel(dev, | |
292 | dma_data->chan_name); | |
293 | ||
d1e1406c | 294 | if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) { |
c999836d LPC |
295 | pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd, |
296 | substream); | |
297 | } | |
298 | ||
28c4468b LPC |
299 | if (!pcm->chan[i]) { |
300 | dev_err(rtd->platform->dev, | |
301 | "Missing dma channel for stream: %d\n", i); | |
de7621e8 | 302 | return -EINVAL; |
28c4468b LPC |
303 | } |
304 | ||
305 | ret = snd_pcm_lib_preallocate_pages(substream, | |
ca2b0295 | 306 | SNDRV_DMA_TYPE_DEV_IRAM, |
28c4468b | 307 | dmaengine_dma_dev(pcm, substream), |
fa654e08 LPC |
308 | prealloc_buffer_size, |
309 | max_buffer_size); | |
28c4468b | 310 | if (ret) |
de7621e8 | 311 | return ret; |
478028e0 | 312 | |
acde50a7 | 313 | if (!dmaengine_pcm_can_report_residue(dev, pcm->chan[i])) |
478028e0 | 314 | pcm->flags |= SND_DMAENGINE_PCM_FLAG_NO_RESIDUE; |
28c4468b LPC |
315 | } |
316 | ||
317 | return 0; | |
28c4468b LPC |
318 | } |
319 | ||
93b943ed LPC |
320 | static snd_pcm_uframes_t dmaengine_pcm_pointer( |
321 | struct snd_pcm_substream *substream) | |
322 | { | |
323 | struct snd_soc_pcm_runtime *rtd = substream->private_data; | |
324 | struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform); | |
325 | ||
326 | if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE) | |
327 | return snd_dmaengine_pcm_pointer_no_residue(substream); | |
328 | else | |
329 | return snd_dmaengine_pcm_pointer(substream); | |
330 | } | |
331 | ||
28c4468b LPC |
332 | static const struct snd_pcm_ops dmaengine_pcm_ops = { |
333 | .open = dmaengine_pcm_open, | |
334 | .close = snd_dmaengine_pcm_close, | |
335 | .ioctl = snd_pcm_lib_ioctl, | |
336 | .hw_params = dmaengine_pcm_hw_params, | |
337 | .hw_free = snd_pcm_lib_free_pages, | |
338 | .trigger = snd_dmaengine_pcm_trigger, | |
93b943ed | 339 | .pointer = dmaengine_pcm_pointer, |
28c4468b LPC |
340 | }; |
341 | ||
342 | static const struct snd_soc_platform_driver dmaengine_pcm_platform = { | |
f1d45cc3 LPC |
343 | .component_driver = { |
344 | .probe_order = SND_SOC_COMP_ORDER_LATE, | |
345 | }, | |
28c4468b LPC |
346 | .ops = &dmaengine_pcm_ops, |
347 | .pcm_new = dmaengine_pcm_new, | |
28c4468b LPC |
348 | }; |
349 | ||
350 | static const char * const dmaengine_pcm_dma_channel_names[] = { | |
351 | [SNDRV_PCM_STREAM_PLAYBACK] = "tx", | |
352 | [SNDRV_PCM_STREAM_CAPTURE] = "rx", | |
353 | }; | |
354 | ||
5eda87b8 | 355 | static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm, |
194c7dea | 356 | struct device *dev, const struct snd_dmaengine_pcm_config *config) |
d1e1406c LPC |
357 | { |
358 | unsigned int i; | |
11b3a7ad | 359 | const char *name; |
5eda87b8 | 360 | struct dma_chan *chan; |
d1e1406c | 361 | |
ea73b7dd MB |
362 | if ((pcm->flags & (SND_DMAENGINE_PCM_FLAG_NO_DT | |
363 | SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) || | |
364 | !dev->of_node) | |
5eda87b8 | 365 | return 0; |
d1e1406c | 366 | |
2b67f8ba | 367 | if (config && config->dma_dev) { |
194c7dea SW |
368 | /* |
369 | * If this warning is seen, it probably means that your Linux | |
370 | * device structure does not match your HW device structure. | |
371 | * It would be best to refactor the Linux device structure to | |
372 | * correctly match the HW structure. | |
373 | */ | |
374 | dev_warn(dev, "DMA channels sourced from device %s", | |
375 | dev_name(config->dma_dev)); | |
376 | dev = config->dma_dev; | |
377 | } | |
378 | ||
11b3a7ad SW |
379 | for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; |
380 | i++) { | |
381 | if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) | |
382 | name = "rx-tx"; | |
383 | else | |
384 | name = dmaengine_pcm_dma_channel_names[i]; | |
2b67f8ba | 385 | if (config && config->chan_names[i]) |
194c7dea | 386 | name = config->chan_names[i]; |
5eda87b8 SW |
387 | chan = dma_request_slave_channel_reason(dev, name); |
388 | if (IS_ERR(chan)) { | |
e9036c2a | 389 | if (PTR_ERR(chan) == -EPROBE_DEFER) |
5eda87b8 SW |
390 | return -EPROBE_DEFER; |
391 | pcm->chan[i] = NULL; | |
392 | } else { | |
393 | pcm->chan[i] = chan; | |
394 | } | |
11b3a7ad SW |
395 | if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) |
396 | break; | |
d1e1406c | 397 | } |
11b3a7ad SW |
398 | |
399 | if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) | |
400 | pcm->chan[1] = pcm->chan[0]; | |
5eda87b8 SW |
401 | |
402 | return 0; | |
d1e1406c LPC |
403 | } |
404 | ||
6b9f3e65 SW |
405 | static void dmaengine_pcm_release_chan(struct dmaengine_pcm *pcm) |
406 | { | |
407 | unsigned int i; | |
408 | ||
409 | for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; | |
410 | i++) { | |
411 | if (!pcm->chan[i]) | |
412 | continue; | |
413 | dma_release_channel(pcm->chan[i]); | |
414 | if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) | |
415 | break; | |
416 | } | |
417 | } | |
418 | ||
28c4468b LPC |
419 | /** |
420 | * snd_dmaengine_pcm_register - Register a dmaengine based PCM device | |
421 | * @dev: The parent device for the PCM device | |
422 | * @config: Platform specific PCM configuration | |
423 | * @flags: Platform specific quirks | |
424 | */ | |
425 | int snd_dmaengine_pcm_register(struct device *dev, | |
426 | const struct snd_dmaengine_pcm_config *config, unsigned int flags) | |
427 | { | |
428 | struct dmaengine_pcm *pcm; | |
6b9f3e65 | 429 | int ret; |
28c4468b | 430 | |
28c4468b LPC |
431 | pcm = kzalloc(sizeof(*pcm), GFP_KERNEL); |
432 | if (!pcm) | |
433 | return -ENOMEM; | |
434 | ||
435 | pcm->config = config; | |
d1e1406c | 436 | pcm->flags = flags; |
28c4468b | 437 | |
5eda87b8 SW |
438 | ret = dmaengine_pcm_request_chan_of(pcm, dev, config); |
439 | if (ret) | |
440 | goto err_free_dma; | |
28c4468b | 441 | |
93b943ed LPC |
442 | ret = snd_soc_add_platform(dev, &pcm->platform, |
443 | &dmaengine_pcm_platform); | |
6b9f3e65 SW |
444 | if (ret) |
445 | goto err_free_dma; | |
446 | ||
447 | return 0; | |
448 | ||
449 | err_free_dma: | |
450 | dmaengine_pcm_release_chan(pcm); | |
451 | kfree(pcm); | |
452 | return ret; | |
28c4468b LPC |
453 | } |
454 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register); | |
455 | ||
456 | /** | |
457 | * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device | |
458 | * @dev: Parent device the PCM was register with | |
459 | * | |
460 | * Removes a dmaengine based PCM device previously registered with | |
461 | * snd_dmaengine_pcm_register. | |
462 | */ | |
463 | void snd_dmaengine_pcm_unregister(struct device *dev) | |
464 | { | |
465 | struct snd_soc_platform *platform; | |
466 | struct dmaengine_pcm *pcm; | |
28c4468b LPC |
467 | |
468 | platform = snd_soc_lookup_platform(dev); | |
469 | if (!platform) | |
470 | return; | |
471 | ||
472 | pcm = soc_platform_to_pcm(platform); | |
473 | ||
28c4468b | 474 | snd_soc_remove_platform(platform); |
6b9f3e65 | 475 | dmaengine_pcm_release_chan(pcm); |
28c4468b LPC |
476 | kfree(pcm); |
477 | } | |
478 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister); | |
479 | ||
480 | MODULE_LICENSE("GPL"); |