30e791a533528042ef5ab42f79064eced53fd681
[muen/linux.git] / sound / soc / soc-generic-dmaengine-pcm.c
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 //  Copyright (C) 2013, Analog Devices Inc.
4 //      Author: Lars-Peter Clausen <lars@metafoo.de>
5
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  * The platforms dmaengine driver does not support reporting the amount of
20  * bytes that are still left to transfer.
21  */
22 #define SND_DMAENGINE_PCM_FLAG_NO_RESIDUE BIT(31)
23
24 struct dmaengine_pcm {
25         struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
26         const struct snd_dmaengine_pcm_config *config;
27         struct snd_soc_component component;
28         unsigned int flags;
29 };
30
31 static struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
32 {
33         return container_of(p, struct dmaengine_pcm, component);
34 }
35
36 static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
37         struct snd_pcm_substream *substream)
38 {
39         if (!pcm->chan[substream->stream])
40                 return NULL;
41
42         return pcm->chan[substream->stream]->device->dev;
43 }
44
45 /**
46  * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
47  * @substream: PCM substream
48  * @params: hw_params
49  * @slave_config: DMA slave config to prepare
50  *
51  * This function can be used as a generic prepare_slave_config callback for
52  * platforms which make use of the snd_dmaengine_dai_dma_data struct for their
53  * DAI DMA data. Internally the function will first call
54  * snd_hwparams_to_dma_slave_config to fill in the slave config based on the
55  * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the
56  * remaining fields based on the DAI DMA data.
57  */
58 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
59         struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
60 {
61         struct snd_soc_pcm_runtime *rtd = substream->private_data;
62         struct snd_dmaengine_dai_dma_data *dma_data;
63         int ret;
64
65         dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
66
67         ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
68         if (ret)
69                 return ret;
70
71         snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
72                 slave_config);
73
74         return 0;
75 }
76 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
77
78 static int dmaengine_pcm_hw_params(struct snd_pcm_substream *substream,
79         struct snd_pcm_hw_params *params)
80 {
81         struct snd_soc_pcm_runtime *rtd = substream->private_data;
82         struct snd_soc_component *component =
83                 snd_soc_rtdcom_lookup(rtd, SND_DMAENGINE_PCM_DRV_NAME);
84         struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
85         struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
86         int (*prepare_slave_config)(struct snd_pcm_substream *substream,
87                         struct snd_pcm_hw_params *params,
88                         struct dma_slave_config *slave_config);
89         struct dma_slave_config slave_config;
90         int ret;
91
92         memset(&slave_config, 0, sizeof(slave_config));
93
94         if (!pcm->config)
95                 prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
96         else
97                 prepare_slave_config = pcm->config->prepare_slave_config;
98
99         if (prepare_slave_config) {
100                 ret = prepare_slave_config(substream, params, &slave_config);
101                 if (ret)
102                         return ret;
103
104                 ret = dmaengine_slave_config(chan, &slave_config);
105                 if (ret)
106                         return ret;
107         }
108
109         return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
110 }
111
112 static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substream)
113 {
114         struct snd_soc_pcm_runtime *rtd = substream->private_data;
115         struct snd_soc_component *component =
116                 snd_soc_rtdcom_lookup(rtd, SND_DMAENGINE_PCM_DRV_NAME);
117         struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
118         struct device *dma_dev = dmaengine_dma_dev(pcm, substream);
119         struct dma_chan *chan = pcm->chan[substream->stream];
120         struct snd_dmaengine_dai_dma_data *dma_data;
121         struct dma_slave_caps dma_caps;
122         struct snd_pcm_hardware hw;
123         u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
124                           BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
125                           BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
126         snd_pcm_format_t i;
127         int ret;
128
129         if (pcm->config && pcm->config->pcm_hardware)
130                 return snd_soc_set_runtime_hwparams(substream,
131                                 pcm->config->pcm_hardware);
132
133         dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
134
135         memset(&hw, 0, sizeof(hw));
136         hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
137                         SNDRV_PCM_INFO_INTERLEAVED;
138         hw.periods_min = 2;
139         hw.periods_max = UINT_MAX;
140         hw.period_bytes_min = 256;
141         hw.period_bytes_max = dma_get_max_seg_size(dma_dev);
142         hw.buffer_bytes_max = SIZE_MAX;
143         hw.fifo_size = dma_data->fifo_size;
144
145         if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
146                 hw.info |= SNDRV_PCM_INFO_BATCH;
147
148         ret = dma_get_slave_caps(chan, &dma_caps);
149         if (ret == 0) {
150                 if (dma_caps.cmd_pause && dma_caps.cmd_resume)
151                         hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
152                 if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT)
153                         hw.info |= SNDRV_PCM_INFO_BATCH;
154
155                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
156                         addr_widths = dma_caps.dst_addr_widths;
157                 else
158                         addr_widths = dma_caps.src_addr_widths;
159         }
160
161         /*
162          * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep
163          * hw.formats set to 0, meaning no restrictions are in place.
164          * In this case it's the responsibility of the DAI driver to
165          * provide the supported format information.
166          */
167         if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK))
168                 /*
169                  * Prepare formats mask for valid/allowed sample types. If the
170                  * dma does not have support for the given physical word size,
171                  * it needs to be masked out so user space can not use the
172                  * format which produces corrupted audio.
173                  * In case the dma driver does not implement the slave_caps the
174                  * default assumption is that it supports 1, 2 and 4 bytes
175                  * widths.
176                  */
177                 for (i = SNDRV_PCM_FORMAT_FIRST; i <= SNDRV_PCM_FORMAT_LAST; i++) {
178                         int bits = snd_pcm_format_physical_width(i);
179
180                         /*
181                          * Enable only samples with DMA supported physical
182                          * widths
183                          */
184                         switch (bits) {
185                         case 8:
186                         case 16:
187                         case 24:
188                         case 32:
189                         case 64:
190                                 if (addr_widths & (1 << (bits / 8)))
191                                         hw.formats |= pcm_format_to_bits(i);
192                                 break;
193                         default:
194                                 /* Unsupported types */
195                                 break;
196                         }
197                 }
198
199         return snd_soc_set_runtime_hwparams(substream, &hw);
200 }
201
202 static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
203 {
204         struct snd_soc_pcm_runtime *rtd = substream->private_data;
205         struct snd_soc_component *component =
206                 snd_soc_rtdcom_lookup(rtd, SND_DMAENGINE_PCM_DRV_NAME);
207         struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
208         struct dma_chan *chan = pcm->chan[substream->stream];
209         int ret;
210
211         ret = dmaengine_pcm_set_runtime_hwparams(substream);
212         if (ret)
213                 return ret;
214
215         return snd_dmaengine_pcm_open(substream, chan);
216 }
217
218 static struct dma_chan *dmaengine_pcm_compat_request_channel(
219         struct snd_soc_pcm_runtime *rtd,
220         struct snd_pcm_substream *substream)
221 {
222         struct snd_soc_component *component =
223                 snd_soc_rtdcom_lookup(rtd, SND_DMAENGINE_PCM_DRV_NAME);
224         struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
225         struct snd_dmaengine_dai_dma_data *dma_data;
226         dma_filter_fn fn = NULL;
227
228         dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
229
230         if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0])
231                 return pcm->chan[0];
232
233         if (pcm->config && pcm->config->compat_request_channel)
234                 return pcm->config->compat_request_channel(rtd, substream);
235
236         if (pcm->config)
237                 fn = pcm->config->compat_filter_fn;
238
239         return snd_dmaengine_pcm_request_channel(fn, dma_data->filter_data);
240 }
241
242 static bool dmaengine_pcm_can_report_residue(struct device *dev,
243         struct dma_chan *chan)
244 {
245         struct dma_slave_caps dma_caps;
246         int ret;
247
248         ret = dma_get_slave_caps(chan, &dma_caps);
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         }
254
255         if (dma_caps.residue_granularity == DMA_RESIDUE_GRANULARITY_DESCRIPTOR)
256                 return false;
257
258         return true;
259 }
260
261 static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
262 {
263         struct snd_soc_component *component =
264                 snd_soc_rtdcom_lookup(rtd, SND_DMAENGINE_PCM_DRV_NAME);
265         struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
266         const struct snd_dmaengine_pcm_config *config = pcm->config;
267         struct device *dev = component->dev;
268         struct snd_dmaengine_dai_dma_data *dma_data;
269         struct snd_pcm_substream *substream;
270         size_t prealloc_buffer_size;
271         size_t max_buffer_size;
272         unsigned int i;
273         int ret;
274
275         if (config && config->prealloc_buffer_size) {
276                 prealloc_buffer_size = config->prealloc_buffer_size;
277                 max_buffer_size = config->pcm_hardware->buffer_bytes_max;
278         } else {
279                 prealloc_buffer_size = 512 * 1024;
280                 max_buffer_size = SIZE_MAX;
281         }
282
283         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
284                 substream = rtd->pcm->streams[i].substream;
285                 if (!substream)
286                         continue;
287
288                 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
289
290                 if (!pcm->chan[i] &&
291                     (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME))
292                         pcm->chan[i] = dma_request_slave_channel(dev,
293                                 dma_data->chan_name);
294
295                 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
296                         pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
297                                 substream);
298                 }
299
300                 if (!pcm->chan[i]) {
301                         dev_err(component->dev,
302                                 "Missing dma channel for stream: %d\n", i);
303                         return -EINVAL;
304                 }
305
306                 ret = snd_pcm_lib_preallocate_pages(substream,
307                                 SNDRV_DMA_TYPE_DEV_IRAM,
308                                 dmaengine_dma_dev(pcm, substream),
309                                 prealloc_buffer_size,
310                                 max_buffer_size);
311                 if (ret)
312                         return ret;
313
314                 if (!dmaengine_pcm_can_report_residue(dev, pcm->chan[i]))
315                         pcm->flags |= SND_DMAENGINE_PCM_FLAG_NO_RESIDUE;
316         }
317
318         return 0;
319 }
320
321 static snd_pcm_uframes_t dmaengine_pcm_pointer(
322         struct snd_pcm_substream *substream)
323 {
324         struct snd_soc_pcm_runtime *rtd = substream->private_data;
325         struct snd_soc_component *component =
326                 snd_soc_rtdcom_lookup(rtd, SND_DMAENGINE_PCM_DRV_NAME);
327         struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
328
329         if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
330                 return snd_dmaengine_pcm_pointer_no_residue(substream);
331         else
332                 return snd_dmaengine_pcm_pointer(substream);
333 }
334
335 static int dmaengine_copy_user(struct snd_pcm_substream *substream,
336                                int channel, unsigned long hwoff,
337                                void __user *buf, unsigned long bytes)
338 {
339         struct snd_soc_pcm_runtime *rtd = substream->private_data;
340         struct snd_soc_component *component =
341                 snd_soc_rtdcom_lookup(rtd, SND_DMAENGINE_PCM_DRV_NAME);
342         struct snd_pcm_runtime *runtime = substream->runtime;
343         struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
344         int (*process)(struct snd_pcm_substream *substream,
345                        int channel, unsigned long hwoff,
346                        void *buf, unsigned long bytes) = pcm->config->process;
347         bool is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
348         void *dma_ptr = runtime->dma_area + hwoff +
349                         channel * (runtime->dma_bytes / runtime->channels);
350         int ret;
351
352         if (is_playback)
353                 if (copy_from_user(dma_ptr, buf, bytes))
354                         return -EFAULT;
355
356         if (process) {
357                 ret = process(substream, channel, hwoff, (__force void *)buf, bytes);
358                 if (ret < 0)
359                         return ret;
360         }
361
362         if (!is_playback)
363                 if (copy_to_user(buf, dma_ptr, bytes))
364                         return -EFAULT;
365
366         return 0;
367 }
368
369 static const struct snd_pcm_ops dmaengine_pcm_ops = {
370         .open           = dmaengine_pcm_open,
371         .close          = snd_dmaengine_pcm_close,
372         .ioctl          = snd_pcm_lib_ioctl,
373         .hw_params      = dmaengine_pcm_hw_params,
374         .hw_free        = snd_pcm_lib_free_pages,
375         .trigger        = snd_dmaengine_pcm_trigger,
376         .pointer        = dmaengine_pcm_pointer,
377 };
378
379 static const struct snd_pcm_ops dmaengine_pcm_process_ops = {
380         .open           = dmaengine_pcm_open,
381         .close          = snd_dmaengine_pcm_close,
382         .ioctl          = snd_pcm_lib_ioctl,
383         .hw_params      = dmaengine_pcm_hw_params,
384         .hw_free        = snd_pcm_lib_free_pages,
385         .trigger        = snd_dmaengine_pcm_trigger,
386         .pointer        = dmaengine_pcm_pointer,
387         .copy_user      = dmaengine_copy_user,
388 };
389
390 static const struct snd_soc_component_driver dmaengine_pcm_component = {
391         .name           = SND_DMAENGINE_PCM_DRV_NAME,
392         .probe_order    = SND_SOC_COMP_ORDER_LATE,
393         .ops            = &dmaengine_pcm_ops,
394         .pcm_new        = dmaengine_pcm_new,
395 };
396
397 static const struct snd_soc_component_driver dmaengine_pcm_component_process = {
398         .name           = SND_DMAENGINE_PCM_DRV_NAME,
399         .probe_order    = SND_SOC_COMP_ORDER_LATE,
400         .ops            = &dmaengine_pcm_process_ops,
401         .pcm_new        = dmaengine_pcm_new,
402 };
403
404 static const char * const dmaengine_pcm_dma_channel_names[] = {
405         [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
406         [SNDRV_PCM_STREAM_CAPTURE] = "rx",
407 };
408
409 static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
410         struct device *dev, const struct snd_dmaengine_pcm_config *config)
411 {
412         unsigned int i;
413         const char *name;
414         struct dma_chan *chan;
415
416         if ((pcm->flags & (SND_DMAENGINE_PCM_FLAG_NO_DT |
417                            SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) ||
418             !dev->of_node)
419                 return 0;
420
421         if (config && config->dma_dev) {
422                 /*
423                  * If this warning is seen, it probably means that your Linux
424                  * device structure does not match your HW device structure.
425                  * It would be best to refactor the Linux device structure to
426                  * correctly match the HW structure.
427                  */
428                 dev_warn(dev, "DMA channels sourced from device %s",
429                          dev_name(config->dma_dev));
430                 dev = config->dma_dev;
431         }
432
433         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE;
434              i++) {
435                 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
436                         name = "rx-tx";
437                 else
438                         name = dmaengine_pcm_dma_channel_names[i];
439                 if (config && config->chan_names[i])
440                         name = config->chan_names[i];
441                 chan = dma_request_slave_channel_reason(dev, name);
442                 if (IS_ERR(chan)) {
443                         if (PTR_ERR(chan) == -EPROBE_DEFER)
444                                 return -EPROBE_DEFER;
445                         pcm->chan[i] = NULL;
446                 } else {
447                         pcm->chan[i] = chan;
448                 }
449                 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
450                         break;
451         }
452
453         if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
454                 pcm->chan[1] = pcm->chan[0];
455
456         return 0;
457 }
458
459 static void dmaengine_pcm_release_chan(struct dmaengine_pcm *pcm)
460 {
461         unsigned int i;
462
463         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE;
464              i++) {
465                 if (!pcm->chan[i])
466                         continue;
467                 dma_release_channel(pcm->chan[i]);
468                 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
469                         break;
470         }
471 }
472
473 /**
474  * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
475  * @dev: The parent device for the PCM device
476  * @config: Platform specific PCM configuration
477  * @flags: Platform specific quirks
478  */
479 int snd_dmaengine_pcm_register(struct device *dev,
480         const struct snd_dmaengine_pcm_config *config, unsigned int flags)
481 {
482         struct dmaengine_pcm *pcm;
483         int ret;
484
485         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
486         if (!pcm)
487                 return -ENOMEM;
488
489 #ifdef CONFIG_DEBUG_FS
490         pcm->component.debugfs_prefix = "dma";
491 #endif
492         pcm->config = config;
493         pcm->flags = flags;
494
495         ret = dmaengine_pcm_request_chan_of(pcm, dev, config);
496         if (ret)
497                 goto err_free_dma;
498
499         if (config && config->process)
500                 ret = snd_soc_add_component(dev, &pcm->component,
501                                             &dmaengine_pcm_component_process,
502                                             NULL, 0);
503         else
504                 ret = snd_soc_add_component(dev, &pcm->component,
505                                             &dmaengine_pcm_component, NULL, 0);
506         if (ret)
507                 goto err_free_dma;
508
509         return 0;
510
511 err_free_dma:
512         dmaengine_pcm_release_chan(pcm);
513         kfree(pcm);
514         return ret;
515 }
516 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
517
518 /**
519  * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
520  * @dev: Parent device the PCM was register with
521  *
522  * Removes a dmaengine based PCM device previously registered with
523  * snd_dmaengine_pcm_register.
524  */
525 void snd_dmaengine_pcm_unregister(struct device *dev)
526 {
527         struct snd_soc_component *component;
528         struct dmaengine_pcm *pcm;
529
530         component = snd_soc_lookup_component(dev, SND_DMAENGINE_PCM_DRV_NAME);
531         if (!component)
532                 return;
533
534         pcm = soc_component_to_pcm(component);
535
536         snd_soc_unregister_component(dev);
537         dmaengine_pcm_release_chan(pcm);
538         kfree(pcm);
539 }
540 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
541
542 MODULE_LICENSE("GPL");