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6#include <linux/module.h>
7#include <linux/init.h>
8#include <linux/dmaengine.h>
9#include <linux/slab.h>
10#include <sound/pcm.h>
11#include <sound/pcm_params.h>
12#include <sound/soc.h>
13#include <linux/dma-mapping.h>
14#include <linux/of.h>
15
16#include <sound/dmaengine_pcm.h>
17
18
19
20
21
22#define SND_DMAENGINE_PCM_FLAG_NO_RESIDUE BIT(31)
23
24static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
25 struct snd_pcm_substream *substream)
26{
27 if (!pcm->chan[substream->stream])
28 return NULL;
29
30 return pcm->chan[substream->stream]->device->dev;
31}
32
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37
38
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41
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43
44
45
46int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
47 struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
48{
49 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
50 struct snd_dmaengine_dai_dma_data *dma_data;
51 int ret;
52
53 if (rtd->num_cpus > 1) {
54 dev_err(rtd->dev,
55 "%s doesn't support Multi CPU yet\n", __func__);
56 return -EINVAL;
57 }
58
59 dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
60
61 ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
62 if (ret)
63 return ret;
64
65 snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
66 slave_config);
67
68 return 0;
69}
70EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
71
72static int dmaengine_pcm_hw_params(struct snd_soc_component *component,
73 struct snd_pcm_substream *substream,
74 struct snd_pcm_hw_params *params)
75{
76 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
77 struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
78 int (*prepare_slave_config)(struct snd_pcm_substream *substream,
79 struct snd_pcm_hw_params *params,
80 struct dma_slave_config *slave_config);
81 struct dma_slave_config slave_config;
82 int ret;
83
84 memset(&slave_config, 0, sizeof(slave_config));
85
86 if (!pcm->config)
87 prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
88 else
89 prepare_slave_config = pcm->config->prepare_slave_config;
90
91 if (prepare_slave_config) {
92 ret = prepare_slave_config(substream, params, &slave_config);
93 if (ret)
94 return ret;
95
96 ret = dmaengine_slave_config(chan, &slave_config);
97 if (ret)
98 return ret;
99 }
100
101 return 0;
102}
103
104static int
105dmaengine_pcm_set_runtime_hwparams(struct snd_soc_component *component,
106 struct snd_pcm_substream *substream)
107{
108 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
109 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
110 struct device *dma_dev = dmaengine_dma_dev(pcm, substream);
111 struct dma_chan *chan = pcm->chan[substream->stream];
112 struct snd_dmaengine_dai_dma_data *dma_data;
113 struct snd_pcm_hardware hw;
114
115 if (rtd->num_cpus > 1) {
116 dev_err(rtd->dev,
117 "%s doesn't support Multi CPU yet\n", __func__);
118 return -EINVAL;
119 }
120
121 if (pcm->config && pcm->config->pcm_hardware)
122 return snd_soc_set_runtime_hwparams(substream,
123 pcm->config->pcm_hardware);
124
125 dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
126
127 memset(&hw, 0, sizeof(hw));
128 hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
129 SNDRV_PCM_INFO_INTERLEAVED;
130 hw.periods_min = 2;
131 hw.periods_max = UINT_MAX;
132 hw.period_bytes_min = 256;
133 hw.period_bytes_max = dma_get_max_seg_size(dma_dev);
134 hw.buffer_bytes_max = SIZE_MAX;
135 hw.fifo_size = dma_data->fifo_size;
136
137 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
138 hw.info |= SNDRV_PCM_INFO_BATCH;
139
140
141
142
143
144
145 snd_dmaengine_pcm_refine_runtime_hwparams(substream,
146 dma_data,
147 &hw,
148 chan);
149
150 return snd_soc_set_runtime_hwparams(substream, &hw);
151}
152
153static int dmaengine_pcm_open(struct snd_soc_component *component,
154 struct snd_pcm_substream *substream)
155{
156 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
157 struct dma_chan *chan = pcm->chan[substream->stream];
158 int ret;
159
160 ret = dmaengine_pcm_set_runtime_hwparams(component, substream);
161 if (ret)
162 return ret;
163
164 return snd_dmaengine_pcm_open(substream, chan);
165}
166
167static int dmaengine_pcm_close(struct snd_soc_component *component,
168 struct snd_pcm_substream *substream)
169{
170 return snd_dmaengine_pcm_close(substream);
171}
172
173static int dmaengine_pcm_trigger(struct snd_soc_component *component,
174 struct snd_pcm_substream *substream, int cmd)
175{
176 return snd_dmaengine_pcm_trigger(substream, cmd);
177}
178
179static struct dma_chan *dmaengine_pcm_compat_request_channel(
180 struct snd_soc_component *component,
181 struct snd_soc_pcm_runtime *rtd,
182 struct snd_pcm_substream *substream)
183{
184 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
185 struct snd_dmaengine_dai_dma_data *dma_data;
186 dma_filter_fn fn = NULL;
187
188 if (rtd->num_cpus > 1) {
189 dev_err(rtd->dev,
190 "%s doesn't support Multi CPU yet\n", __func__);
191 return NULL;
192 }
193
194 dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
195
196 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0])
197 return pcm->chan[0];
198
199 if (pcm->config && pcm->config->compat_request_channel)
200 return pcm->config->compat_request_channel(rtd, substream);
201
202 if (pcm->config)
203 fn = pcm->config->compat_filter_fn;
204
205 return snd_dmaengine_pcm_request_channel(fn, dma_data->filter_data);
206}
207
208static bool dmaengine_pcm_can_report_residue(struct device *dev,
209 struct dma_chan *chan)
210{
211 struct dma_slave_caps dma_caps;
212 int ret;
213
214 ret = dma_get_slave_caps(chan, &dma_caps);
215 if (ret != 0) {
216 dev_warn(dev, "Failed to get DMA channel capabilities, falling back to period counting: %d\n",
217 ret);
218 return false;
219 }
220
221 if (dma_caps.residue_granularity == DMA_RESIDUE_GRANULARITY_DESCRIPTOR)
222 return false;
223
224 return true;
225}
226
227static int dmaengine_pcm_new(struct snd_soc_component *component,
228 struct snd_soc_pcm_runtime *rtd)
229{
230 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
231 const struct snd_dmaengine_pcm_config *config = pcm->config;
232 struct device *dev = component->dev;
233 struct snd_pcm_substream *substream;
234 size_t prealloc_buffer_size;
235 size_t max_buffer_size;
236 unsigned int i;
237
238 if (config && config->prealloc_buffer_size) {
239 prealloc_buffer_size = config->prealloc_buffer_size;
240 max_buffer_size = config->pcm_hardware->buffer_bytes_max;
241 } else {
242 prealloc_buffer_size = 512 * 1024;
243 max_buffer_size = SIZE_MAX;
244 }
245
246 for_each_pcm_streams(i) {
247 substream = rtd->pcm->streams[i].substream;
248 if (!substream)
249 continue;
250
251 if (!pcm->chan[i] && config && config->chan_names[i])
252 pcm->chan[i] = dma_request_slave_channel(dev,
253 config->chan_names[i]);
254
255 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
256 pcm->chan[i] = dmaengine_pcm_compat_request_channel(
257 component, rtd, substream);
258 }
259
260 if (!pcm->chan[i]) {
261 dev_err(component->dev,
262 "Missing dma channel for stream: %d\n", i);
263 return -EINVAL;
264 }
265
266 snd_pcm_set_managed_buffer(substream,
267 SNDRV_DMA_TYPE_DEV_IRAM,
268 dmaengine_dma_dev(pcm, substream),
269 prealloc_buffer_size,
270 max_buffer_size);
271
272 if (!dmaengine_pcm_can_report_residue(dev, pcm->chan[i]))
273 pcm->flags |= SND_DMAENGINE_PCM_FLAG_NO_RESIDUE;
274
275 if (rtd->pcm->streams[i].pcm->name[0] == '\0') {
276 strscpy_pad(rtd->pcm->streams[i].pcm->name,
277 rtd->pcm->streams[i].pcm->id,
278 sizeof(rtd->pcm->streams[i].pcm->name));
279 }
280 }
281
282 return 0;
283}
284
285static snd_pcm_uframes_t dmaengine_pcm_pointer(
286 struct snd_soc_component *component,
287 struct snd_pcm_substream *substream)
288{
289 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
290
291 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
292 return snd_dmaengine_pcm_pointer_no_residue(substream);
293 else
294 return snd_dmaengine_pcm_pointer(substream);
295}
296
297static int dmaengine_copy_user(struct snd_soc_component *component,
298 struct snd_pcm_substream *substream,
299 int channel, unsigned long hwoff,
300 void __user *buf, unsigned long bytes)
301{
302 struct snd_pcm_runtime *runtime = substream->runtime;
303 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
304 int (*process)(struct snd_pcm_substream *substream,
305 int channel, unsigned long hwoff,
306 void *buf, unsigned long bytes) = pcm->config->process;
307 bool is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
308 void *dma_ptr = runtime->dma_area + hwoff +
309 channel * (runtime->dma_bytes / runtime->channels);
310 int ret;
311
312 if (is_playback)
313 if (copy_from_user(dma_ptr, buf, bytes))
314 return -EFAULT;
315
316 if (process) {
317 ret = process(substream, channel, hwoff, (__force void *)buf, bytes);
318 if (ret < 0)
319 return ret;
320 }
321
322 if (!is_playback)
323 if (copy_to_user(buf, dma_ptr, bytes))
324 return -EFAULT;
325
326 return 0;
327}
328
329static const struct snd_soc_component_driver dmaengine_pcm_component = {
330 .name = SND_DMAENGINE_PCM_DRV_NAME,
331 .probe_order = SND_SOC_COMP_ORDER_LATE,
332 .open = dmaengine_pcm_open,
333 .close = dmaengine_pcm_close,
334 .hw_params = dmaengine_pcm_hw_params,
335 .trigger = dmaengine_pcm_trigger,
336 .pointer = dmaengine_pcm_pointer,
337 .pcm_construct = dmaengine_pcm_new,
338};
339
340static const struct snd_soc_component_driver dmaengine_pcm_component_process = {
341 .name = SND_DMAENGINE_PCM_DRV_NAME,
342 .probe_order = SND_SOC_COMP_ORDER_LATE,
343 .open = dmaengine_pcm_open,
344 .close = dmaengine_pcm_close,
345 .hw_params = dmaengine_pcm_hw_params,
346 .trigger = dmaengine_pcm_trigger,
347 .pointer = dmaengine_pcm_pointer,
348 .copy_user = dmaengine_copy_user,
349 .pcm_construct = dmaengine_pcm_new,
350};
351
352static const char * const dmaengine_pcm_dma_channel_names[] = {
353 [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
354 [SNDRV_PCM_STREAM_CAPTURE] = "rx",
355};
356
357static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
358 struct device *dev, const struct snd_dmaengine_pcm_config *config)
359{
360 unsigned int i;
361 const char *name;
362 struct dma_chan *chan;
363
364 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || (!dev->of_node &&
365 !(config && config->dma_dev && config->dma_dev->of_node)))
366 return 0;
367
368 if (config && config->dma_dev) {
369
370
371
372
373
374
375 dev_warn(dev, "DMA channels sourced from device %s",
376 dev_name(config->dma_dev));
377 dev = config->dma_dev;
378 }
379
380 for_each_pcm_streams(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];
385 if (config && config->chan_names[i])
386 name = config->chan_names[i];
387 chan = dma_request_chan(dev, name);
388 if (IS_ERR(chan)) {
389
390
391
392
393
394 if (PTR_ERR(chan) == -EPROBE_DEFER)
395 return -EPROBE_DEFER;
396 pcm->chan[i] = NULL;
397 } else {
398 pcm->chan[i] = chan;
399 }
400 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
401 break;
402 }
403
404 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
405 pcm->chan[1] = pcm->chan[0];
406
407 return 0;
408}
409
410static void dmaengine_pcm_release_chan(struct dmaengine_pcm *pcm)
411{
412 unsigned int i;
413
414 for_each_pcm_streams(i) {
415 if (!pcm->chan[i])
416 continue;
417 dma_release_channel(pcm->chan[i]);
418 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
419 break;
420 }
421}
422
423
424
425
426
427
428
429int snd_dmaengine_pcm_register(struct device *dev,
430 const struct snd_dmaengine_pcm_config *config, unsigned int flags)
431{
432 const struct snd_soc_component_driver *driver;
433 struct dmaengine_pcm *pcm;
434 int ret;
435
436 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
437 if (!pcm)
438 return -ENOMEM;
439
440#ifdef CONFIG_DEBUG_FS
441 pcm->component.debugfs_prefix = "dma";
442#endif
443 pcm->config = config;
444 pcm->flags = flags;
445
446 ret = dmaengine_pcm_request_chan_of(pcm, dev, config);
447 if (ret)
448 goto err_free_dma;
449
450 if (config && config->process)
451 driver = &dmaengine_pcm_component_process;
452 else
453 driver = &dmaengine_pcm_component;
454
455 ret = snd_soc_component_initialize(&pcm->component, driver, dev);
456 if (ret)
457 goto err_free_dma;
458
459 ret = snd_soc_add_component(&pcm->component, NULL, 0);
460 if (ret)
461 goto err_free_dma;
462
463 return 0;
464
465err_free_dma:
466 dmaengine_pcm_release_chan(pcm);
467 kfree(pcm);
468 return ret;
469}
470EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
471
472
473
474
475
476
477
478
479void snd_dmaengine_pcm_unregister(struct device *dev)
480{
481 struct snd_soc_component *component;
482 struct dmaengine_pcm *pcm;
483
484 component = snd_soc_lookup_component(dev, SND_DMAENGINE_PCM_DRV_NAME);
485 if (!component)
486 return;
487
488 pcm = soc_component_to_pcm(component);
489
490 snd_soc_unregister_component_by_driver(dev, component->driver);
491 dmaengine_pcm_release_chan(pcm);
492 kfree(pcm);
493}
494EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
495
496MODULE_LICENSE("GPL");
497
