xref: /openbmc/linux/sound/soc/sprd/sprd-pcm-dma.c (revision 15e3ae36)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2019 Spreadtrum Communications Inc.
3 
4 #include <linux/dma-mapping.h>
5 #include <linux/dmaengine.h>
6 #include <linux/dma/sprd-dma.h>
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/of_reserved_mem.h>
10 #include <linux/platform_device.h>
11 #include <sound/pcm.h>
12 #include <sound/pcm_params.h>
13 #include <sound/soc.h>
14 
15 #include "sprd-pcm-dma.h"
16 
17 #define SPRD_PCM_DMA_LINKLIST_SIZE	64
18 #define SPRD_PCM_DMA_BRUST_LEN		640
19 
20 struct sprd_pcm_dma_data {
21 	struct dma_chan *chan;
22 	struct dma_async_tx_descriptor *desc;
23 	dma_cookie_t cookie;
24 	dma_addr_t phys;
25 	void *virt;
26 	int pre_pointer;
27 };
28 
29 struct sprd_pcm_dma_private {
30 	struct snd_pcm_substream *substream;
31 	struct sprd_pcm_dma_params *params;
32 	struct sprd_pcm_dma_data data[SPRD_PCM_CHANNEL_MAX];
33 	int hw_chan;
34 	int dma_addr_offset;
35 };
36 
37 static const struct snd_pcm_hardware sprd_pcm_hardware = {
38 	.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
39 		SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_PAUSE |
40 		SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_NO_PERIOD_WAKEUP,
41 	.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE,
42 	.period_bytes_min = 1,
43 	.period_bytes_max = 64 * 1024,
44 	.periods_min = 1,
45 	.periods_max = PAGE_SIZE / SPRD_PCM_DMA_LINKLIST_SIZE,
46 	.buffer_bytes_max = 64 * 1024,
47 };
48 
49 static int sprd_pcm_open(struct snd_soc_component *component,
50 			 struct snd_pcm_substream *substream)
51 {
52 	struct snd_pcm_runtime *runtime = substream->runtime;
53 	struct device *dev = component->dev;
54 	struct sprd_pcm_dma_private *dma_private;
55 	int hw_chan = SPRD_PCM_CHANNEL_MAX;
56 	int size, ret, i;
57 
58 	snd_soc_set_runtime_hwparams(substream, &sprd_pcm_hardware);
59 
60 	ret = snd_pcm_hw_constraint_step(runtime, 0,
61 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
62 					 SPRD_PCM_DMA_BRUST_LEN);
63 	if (ret < 0)
64 		return ret;
65 
66 	ret = snd_pcm_hw_constraint_step(runtime, 0,
67 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
68 					 SPRD_PCM_DMA_BRUST_LEN);
69 	if (ret < 0)
70 		return ret;
71 
72 	ret = snd_pcm_hw_constraint_integer(runtime,
73 					    SNDRV_PCM_HW_PARAM_PERIODS);
74 	if (ret < 0)
75 		return ret;
76 
77 	dma_private = devm_kzalloc(dev, sizeof(*dma_private), GFP_KERNEL);
78 	if (!dma_private)
79 		return -ENOMEM;
80 
81 	size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
82 
83 	for (i = 0; i < hw_chan; i++) {
84 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
85 
86 		data->virt = dmam_alloc_coherent(dev, size, &data->phys,
87 						 GFP_KERNEL);
88 		if (!data->virt) {
89 			ret = -ENOMEM;
90 			goto error;
91 		}
92 	}
93 
94 	dma_private->hw_chan = hw_chan;
95 	runtime->private_data = dma_private;
96 	dma_private->substream = substream;
97 
98 	return 0;
99 
100 error:
101 	for (i = 0; i < hw_chan; i++) {
102 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
103 
104 		if (data->virt)
105 			dmam_free_coherent(dev, size, data->virt, data->phys);
106 	}
107 
108 	devm_kfree(dev, dma_private);
109 	return ret;
110 }
111 
112 static int sprd_pcm_close(struct snd_soc_component *component,
113 			  struct snd_pcm_substream *substream)
114 {
115 	struct snd_pcm_runtime *runtime = substream->runtime;
116 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
117 	struct device *dev = component->dev;
118 	int size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
119 	int i;
120 
121 	for (i = 0; i < dma_private->hw_chan; i++) {
122 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
123 
124 		dmam_free_coherent(dev, size, data->virt, data->phys);
125 	}
126 
127 	devm_kfree(dev, dma_private);
128 
129 	return 0;
130 }
131 
132 static void sprd_pcm_dma_complete(void *data)
133 {
134 	struct sprd_pcm_dma_private *dma_private = data;
135 	struct snd_pcm_substream *substream = dma_private->substream;
136 
137 	snd_pcm_period_elapsed(substream);
138 }
139 
140 static void sprd_pcm_release_dma_channel(struct snd_pcm_substream *substream)
141 {
142 	struct snd_pcm_runtime *runtime = substream->runtime;
143 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
144 	int i;
145 
146 	for (i = 0; i < SPRD_PCM_CHANNEL_MAX; i++) {
147 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
148 
149 		if (data->chan) {
150 			dma_release_channel(data->chan);
151 			data->chan = NULL;
152 		}
153 	}
154 }
155 
156 static int sprd_pcm_request_dma_channel(struct snd_soc_component *component,
157 					struct snd_pcm_substream *substream,
158 					int channels)
159 {
160 	struct snd_pcm_runtime *runtime = substream->runtime;
161 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
162 	struct device *dev = component->dev;
163 	struct sprd_pcm_dma_params *dma_params = dma_private->params;
164 	int i;
165 
166 	if (channels > SPRD_PCM_CHANNEL_MAX) {
167 		dev_err(dev, "invalid dma channel number:%d\n", channels);
168 		return -EINVAL;
169 	}
170 
171 	for (i = 0; i < channels; i++) {
172 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
173 
174 		data->chan = dma_request_slave_channel(dev,
175 						       dma_params->chan_name[i]);
176 		if (!data->chan) {
177 			dev_err(dev, "failed to request dma channel:%s\n",
178 				dma_params->chan_name[i]);
179 			sprd_pcm_release_dma_channel(substream);
180 			return -ENODEV;
181 		}
182 	}
183 
184 	return 0;
185 }
186 
187 static int sprd_pcm_hw_params(struct snd_soc_component *component,
188 			      struct snd_pcm_substream *substream,
189 			      struct snd_pcm_hw_params *params)
190 {
191 	struct snd_pcm_runtime *runtime = substream->runtime;
192 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
193 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
194 	struct sprd_pcm_dma_params *dma_params;
195 	size_t totsize = params_buffer_bytes(params);
196 	size_t period = params_period_bytes(params);
197 	int channels = params_channels(params);
198 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
199 	struct scatterlist *sg;
200 	unsigned long flags;
201 	int ret, i, j, sg_num;
202 
203 	dma_params = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
204 	if (!dma_params) {
205 		dev_warn(component->dev, "no dma parameters setting\n");
206 		dma_private->params = NULL;
207 		snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
208 		runtime->dma_bytes = totsize;
209 		return 0;
210 	}
211 
212 	if (!dma_private->params) {
213 		dma_private->params = dma_params;
214 		ret = sprd_pcm_request_dma_channel(component,
215 						   substream, channels);
216 		if (ret)
217 			return ret;
218 	}
219 
220 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
221 
222 	runtime->dma_bytes = totsize;
223 	sg_num = totsize / period;
224 	dma_private->dma_addr_offset = totsize / channels;
225 
226 	sg = devm_kcalloc(component->dev, sg_num, sizeof(*sg), GFP_KERNEL);
227 	if (!sg) {
228 		ret = -ENOMEM;
229 		goto sg_err;
230 	}
231 
232 	for (i = 0; i < channels; i++) {
233 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
234 		struct dma_chan *chan = data->chan;
235 		struct dma_slave_config config = { };
236 		struct sprd_dma_linklist link = { };
237 		enum dma_transfer_direction dir;
238 		struct scatterlist *sgt = sg;
239 
240 		config.src_maxburst = dma_params->fragment_len[i];
241 		config.src_addr_width = dma_params->datawidth[i];
242 		config.dst_addr_width = dma_params->datawidth[i];
243 		if (is_playback) {
244 			config.src_addr = runtime->dma_addr +
245 				i * dma_private->dma_addr_offset;
246 			config.dst_addr = dma_params->dev_phys[i];
247 			dir = DMA_MEM_TO_DEV;
248 		} else {
249 			config.src_addr = dma_params->dev_phys[i];
250 			config.dst_addr = runtime->dma_addr +
251 				i * dma_private->dma_addr_offset;
252 			dir = DMA_DEV_TO_MEM;
253 		}
254 
255 		sg_init_table(sgt, sg_num);
256 		for (j = 0; j < sg_num; j++, sgt++) {
257 			u32 sg_len = period / channels;
258 
259 			sg_dma_len(sgt) = sg_len;
260 			sg_dma_address(sgt) = runtime->dma_addr +
261 				i * dma_private->dma_addr_offset + sg_len * j;
262 		}
263 
264 		/*
265 		 * Configure the link-list address for the DMA engine link-list
266 		 * mode.
267 		 */
268 		link.virt_addr = (unsigned long)data->virt;
269 		link.phy_addr = data->phys;
270 
271 		ret = dmaengine_slave_config(chan, &config);
272 		if (ret) {
273 			dev_err(component->dev,
274 				"failed to set slave configuration: %d\n", ret);
275 			goto config_err;
276 		}
277 
278 		/*
279 		 * We configure the DMA request mode, interrupt mode, channel
280 		 * mode and channel trigger mode by the flags.
281 		 */
282 		flags = SPRD_DMA_FLAGS(SPRD_DMA_CHN_MODE_NONE, SPRD_DMA_NO_TRG,
283 				       SPRD_DMA_FRAG_REQ, SPRD_DMA_TRANS_INT);
284 		data->desc = chan->device->device_prep_slave_sg(chan, sg,
285 								sg_num, dir,
286 								flags, &link);
287 		if (!data->desc) {
288 			dev_err(component->dev, "failed to prepare slave sg\n");
289 			ret = -ENOMEM;
290 			goto config_err;
291 		}
292 
293 		if (!runtime->no_period_wakeup) {
294 			data->desc->callback = sprd_pcm_dma_complete;
295 			data->desc->callback_param = dma_private;
296 		}
297 	}
298 
299 	devm_kfree(component->dev, sg);
300 
301 	return 0;
302 
303 config_err:
304 	devm_kfree(component->dev, sg);
305 sg_err:
306 	sprd_pcm_release_dma_channel(substream);
307 	return ret;
308 }
309 
310 static int sprd_pcm_hw_free(struct snd_soc_component *component,
311 			    struct snd_pcm_substream *substream)
312 {
313 	snd_pcm_set_runtime_buffer(substream, NULL);
314 	sprd_pcm_release_dma_channel(substream);
315 
316 	return 0;
317 }
318 
319 static int sprd_pcm_trigger(struct snd_soc_component *component,
320 			    struct snd_pcm_substream *substream, int cmd)
321 {
322 	struct sprd_pcm_dma_private *dma_private =
323 		substream->runtime->private_data;
324 	int ret = 0, i;
325 
326 	switch (cmd) {
327 	case SNDRV_PCM_TRIGGER_START:
328 		for (i = 0; i < dma_private->hw_chan; i++) {
329 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
330 
331 			if (!data->desc)
332 				continue;
333 
334 			data->cookie = dmaengine_submit(data->desc);
335 			ret = dma_submit_error(data->cookie);
336 			if (ret) {
337 				dev_err(component->dev,
338 					"failed to submit dma request: %d\n",
339 					ret);
340 				return ret;
341 			}
342 
343 			dma_async_issue_pending(data->chan);
344 		}
345 
346 		break;
347 	case SNDRV_PCM_TRIGGER_RESUME:
348 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
349 		for (i = 0; i < dma_private->hw_chan; i++) {
350 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
351 
352 			if (data->chan)
353 				dmaengine_resume(data->chan);
354 		}
355 
356 		break;
357 	case SNDRV_PCM_TRIGGER_STOP:
358 		for (i = 0; i < dma_private->hw_chan; i++) {
359 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
360 
361 			if (data->chan)
362 				dmaengine_terminate_async(data->chan);
363 		}
364 
365 		break;
366 	case SNDRV_PCM_TRIGGER_SUSPEND:
367 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
368 		for (i = 0; i < dma_private->hw_chan; i++) {
369 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
370 
371 			if (data->chan)
372 				dmaengine_pause(data->chan);
373 		}
374 
375 		break;
376 	default:
377 		ret = -EINVAL;
378 	}
379 
380 	return ret;
381 }
382 
383 static snd_pcm_uframes_t sprd_pcm_pointer(struct snd_soc_component *component,
384 					  struct snd_pcm_substream *substream)
385 {
386 	struct snd_pcm_runtime *runtime = substream->runtime;
387 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
388 	int pointer[SPRD_PCM_CHANNEL_MAX];
389 	int bytes_of_pointer = 0, sel_max = 0, i;
390 	snd_pcm_uframes_t x;
391 	struct dma_tx_state state;
392 	enum dma_status status;
393 
394 	for (i = 0; i < dma_private->hw_chan; i++) {
395 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
396 
397 		if (!data->chan)
398 			continue;
399 
400 		status = dmaengine_tx_status(data->chan, data->cookie, &state);
401 		if (status == DMA_ERROR) {
402 			dev_err(component->dev,
403 				"failed to get dma channel %d status\n", i);
404 			return 0;
405 		}
406 
407 		/*
408 		 * We just get current transfer address from the DMA engine, so
409 		 * we need convert to current pointer.
410 		 */
411 		pointer[i] = state.residue - runtime->dma_addr -
412 			i * dma_private->dma_addr_offset;
413 
414 		if (i == 0) {
415 			bytes_of_pointer = pointer[i];
416 			sel_max = pointer[i] < data->pre_pointer ? 1 : 0;
417 		} else {
418 			sel_max ^= pointer[i] < data->pre_pointer ? 1 : 0;
419 
420 			if (sel_max)
421 				bytes_of_pointer =
422 					max(pointer[i], pointer[i - 1]) << 1;
423 			else
424 				bytes_of_pointer =
425 					min(pointer[i], pointer[i - 1]) << 1;
426 		}
427 
428 		data->pre_pointer = pointer[i];
429 	}
430 
431 	x = bytes_to_frames(runtime, bytes_of_pointer);
432 	if (x == runtime->buffer_size)
433 		x = 0;
434 
435 	return x;
436 }
437 
438 static int sprd_pcm_mmap(struct snd_soc_component *component,
439 			 struct snd_pcm_substream *substream,
440 			 struct vm_area_struct *vma)
441 {
442 	struct snd_pcm_runtime *runtime = substream->runtime;
443 
444 	vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
445 	return remap_pfn_range(vma, vma->vm_start,
446 			       runtime->dma_addr >> PAGE_SHIFT,
447 			       vma->vm_end - vma->vm_start,
448 			       vma->vm_page_prot);
449 }
450 
451 static int sprd_pcm_new(struct snd_soc_component *component,
452 			struct snd_soc_pcm_runtime *rtd)
453 {
454 	struct snd_card *card = rtd->card->snd_card;
455 	struct snd_pcm *pcm = rtd->pcm;
456 	struct snd_pcm_substream *substream;
457 	int ret;
458 
459 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
460 	if (ret)
461 		return ret;
462 
463 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
464 	if (substream) {
465 		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev,
466 					  sprd_pcm_hardware.buffer_bytes_max,
467 					  &substream->dma_buffer);
468 		if (ret) {
469 			dev_err(card->dev,
470 				"can't alloc playback dma buffer: %d\n", ret);
471 			return ret;
472 		}
473 	}
474 
475 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
476 	if (substream) {
477 		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev,
478 					  sprd_pcm_hardware.buffer_bytes_max,
479 					  &substream->dma_buffer);
480 		if (ret) {
481 			dev_err(card->dev,
482 				"can't alloc capture dma buffer: %d\n", ret);
483 			snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
484 			return ret;
485 		}
486 	}
487 
488 	return 0;
489 }
490 
491 static void sprd_pcm_free(struct snd_soc_component *component,
492 			  struct snd_pcm *pcm)
493 {
494 	struct snd_pcm_substream *substream;
495 	int i;
496 
497 	for (i = 0; i < ARRAY_SIZE(pcm->streams); i++) {
498 		substream = pcm->streams[i].substream;
499 		if (substream) {
500 			snd_dma_free_pages(&substream->dma_buffer);
501 			substream->dma_buffer.area = NULL;
502 			substream->dma_buffer.addr = 0;
503 		}
504 	}
505 }
506 
507 static const struct snd_soc_component_driver sprd_soc_component = {
508 	.name		= DRV_NAME,
509 	.open		= sprd_pcm_open,
510 	.close		= sprd_pcm_close,
511 	.hw_params	= sprd_pcm_hw_params,
512 	.hw_free	= sprd_pcm_hw_free,
513 	.trigger	= sprd_pcm_trigger,
514 	.pointer	= sprd_pcm_pointer,
515 	.mmap		= sprd_pcm_mmap,
516 	.pcm_construct	= sprd_pcm_new,
517 	.pcm_destruct	= sprd_pcm_free,
518 	.compr_ops	= &sprd_platform_compr_ops,
519 };
520 
521 static int sprd_soc_platform_probe(struct platform_device *pdev)
522 {
523 	struct device_node *np = pdev->dev.of_node;
524 	int ret;
525 
526 	ret = of_reserved_mem_device_init_by_idx(&pdev->dev, np, 0);
527 	if (ret)
528 		dev_warn(&pdev->dev,
529 			 "no reserved DMA memory for audio platform device\n");
530 
531 	ret = devm_snd_soc_register_component(&pdev->dev, &sprd_soc_component,
532 					      NULL, 0);
533 	if (ret)
534 		dev_err(&pdev->dev, "could not register platform:%d\n", ret);
535 
536 	return ret;
537 }
538 
539 static const struct of_device_id sprd_pcm_of_match[] = {
540 	{ .compatible = "sprd,pcm-platform", },
541 	{ },
542 };
543 MODULE_DEVICE_TABLE(of, sprd_pcm_of_match);
544 
545 static struct platform_driver sprd_pcm_driver = {
546 	.driver = {
547 		.name = "sprd-pcm-audio",
548 		.of_match_table = sprd_pcm_of_match,
549 	},
550 
551 	.probe = sprd_soc_platform_probe,
552 };
553 
554 module_platform_driver(sprd_pcm_driver);
555 
556 MODULE_DESCRIPTION("Spreadtrum ASoC PCM DMA");
557 MODULE_LICENSE("GPL v2");
558 MODULE_ALIAS("platform:sprd-audio");
559