xref: /openbmc/linux/sound/soc/sprd/sprd-pcm-dma.c (revision e657c18a)
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/platform_device.h>
10 #include <sound/pcm.h>
11 #include <sound/pcm_params.h>
12 #include <sound/soc.h>
13 
14 #include "sprd-pcm-dma.h"
15 
16 #define SPRD_PCM_DMA_LINKLIST_SIZE	64
17 #define SPRD_PCM_DMA_BRUST_LEN		640
18 
19 struct sprd_pcm_dma_data {
20 	struct dma_chan *chan;
21 	struct dma_async_tx_descriptor *desc;
22 	dma_cookie_t cookie;
23 	dma_addr_t phys;
24 	void *virt;
25 	int pre_pointer;
26 };
27 
28 struct sprd_pcm_dma_private {
29 	struct snd_pcm_substream *substream;
30 	struct sprd_pcm_dma_params *params;
31 	struct sprd_pcm_dma_data data[SPRD_PCM_CHANNEL_MAX];
32 	int hw_chan;
33 	int dma_addr_offset;
34 };
35 
36 static const struct snd_pcm_hardware sprd_pcm_hardware = {
37 	.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
38 		SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_PAUSE |
39 		SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_NO_PERIOD_WAKEUP,
40 	.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE,
41 	.period_bytes_min = 1,
42 	.period_bytes_max = 64 * 1024,
43 	.periods_min = 1,
44 	.periods_max = PAGE_SIZE / SPRD_PCM_DMA_LINKLIST_SIZE,
45 	.buffer_bytes_max = 64 * 1024,
46 };
47 
48 static int sprd_pcm_open(struct snd_pcm_substream *substream)
49 {
50 	struct snd_pcm_runtime *runtime = substream->runtime;
51 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
52 	struct snd_soc_component *component =
53 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
54 	struct device *dev = component->dev;
55 	struct sprd_pcm_dma_private *dma_private;
56 	int hw_chan = SPRD_PCM_CHANNEL_MAX;
57 	int size, ret, i;
58 
59 	snd_soc_set_runtime_hwparams(substream, &sprd_pcm_hardware);
60 
61 	ret = snd_pcm_hw_constraint_step(runtime, 0,
62 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
63 					 SPRD_PCM_DMA_BRUST_LEN);
64 	if (ret < 0)
65 		return ret;
66 
67 	ret = snd_pcm_hw_constraint_step(runtime, 0,
68 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
69 					 SPRD_PCM_DMA_BRUST_LEN);
70 	if (ret < 0)
71 		return ret;
72 
73 	ret = snd_pcm_hw_constraint_integer(runtime,
74 					    SNDRV_PCM_HW_PARAM_PERIODS);
75 	if (ret < 0)
76 		return ret;
77 
78 	dma_private = devm_kzalloc(dev, sizeof(*dma_private), GFP_KERNEL);
79 	if (!dma_private)
80 		return -ENOMEM;
81 
82 	size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
83 
84 	for (i = 0; i < hw_chan; i++) {
85 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
86 
87 		data->virt = dmam_alloc_coherent(dev, size, &data->phys,
88 						 GFP_KERNEL);
89 		if (!data->virt) {
90 			ret = -ENOMEM;
91 			goto error;
92 		}
93 	}
94 
95 	dma_private->hw_chan = hw_chan;
96 	runtime->private_data = dma_private;
97 	dma_private->substream = substream;
98 
99 	return 0;
100 
101 error:
102 	for (i = 0; i < hw_chan; i++) {
103 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
104 
105 		if (data->virt)
106 			dmam_free_coherent(dev, size, data->virt, data->phys);
107 	}
108 
109 	devm_kfree(dev, dma_private);
110 	return ret;
111 }
112 
113 static int sprd_pcm_close(struct snd_pcm_substream *substream)
114 {
115 	struct snd_pcm_runtime *runtime = substream->runtime;
116 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
117 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
118 	struct snd_soc_component *component =
119 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
120 	struct device *dev = component->dev;
121 	int size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
122 	int i;
123 
124 	for (i = 0; i < dma_private->hw_chan; i++) {
125 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
126 
127 		dmam_free_coherent(dev, size, data->virt, data->phys);
128 	}
129 
130 	devm_kfree(dev, dma_private);
131 
132 	return 0;
133 }
134 
135 static void sprd_pcm_dma_complete(void *data)
136 {
137 	struct sprd_pcm_dma_private *dma_private = data;
138 	struct snd_pcm_substream *substream = dma_private->substream;
139 
140 	snd_pcm_period_elapsed(substream);
141 }
142 
143 static void sprd_pcm_release_dma_channel(struct snd_pcm_substream *substream)
144 {
145 	struct snd_pcm_runtime *runtime = substream->runtime;
146 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
147 	int i;
148 
149 	for (i = 0; i < SPRD_PCM_CHANNEL_MAX; i++) {
150 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
151 
152 		if (data->chan) {
153 			dma_release_channel(data->chan);
154 			data->chan = NULL;
155 		}
156 	}
157 }
158 
159 static int sprd_pcm_request_dma_channel(struct snd_pcm_substream *substream,
160 					int channels)
161 {
162 	struct snd_pcm_runtime *runtime = substream->runtime;
163 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
164 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
165 	struct snd_soc_component *component =
166 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
167 	struct device *dev = component->dev;
168 	struct sprd_pcm_dma_params *dma_params = dma_private->params;
169 	int i;
170 
171 	if (channels > SPRD_PCM_CHANNEL_MAX) {
172 		dev_err(dev, "invalid dma channel number:%d\n", channels);
173 		return -EINVAL;
174 	}
175 
176 	for (i = 0; i < channels; i++) {
177 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
178 
179 		data->chan = dma_request_slave_channel(dev,
180 						       dma_params->chan_name[i]);
181 		if (!data->chan) {
182 			dev_err(dev, "failed to request dma channel:%s\n",
183 				dma_params->chan_name[i]);
184 			sprd_pcm_release_dma_channel(substream);
185 			return -ENODEV;
186 		}
187 	}
188 
189 	return 0;
190 }
191 
192 static int sprd_pcm_hw_params(struct snd_pcm_substream *substream,
193 			      struct snd_pcm_hw_params *params)
194 {
195 	struct snd_pcm_runtime *runtime = substream->runtime;
196 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
197 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
198 	struct snd_soc_component *component =
199 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
200 	struct sprd_pcm_dma_params *dma_params;
201 	size_t totsize = params_buffer_bytes(params);
202 	size_t period = params_period_bytes(params);
203 	int channels = params_channels(params);
204 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
205 	struct scatterlist *sg;
206 	unsigned long flags;
207 	int ret, i, j, sg_num;
208 
209 	dma_params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
210 	if (!dma_params) {
211 		dev_warn(component->dev, "no dma parameters setting\n");
212 		dma_private->params = NULL;
213 		snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
214 		runtime->dma_bytes = totsize;
215 		return 0;
216 	}
217 
218 	if (!dma_private->params) {
219 		dma_private->params = dma_params;
220 		ret = sprd_pcm_request_dma_channel(substream, channels);
221 		if (ret)
222 			return ret;
223 	}
224 
225 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
226 
227 	runtime->dma_bytes = totsize;
228 	sg_num = totsize / period;
229 	dma_private->dma_addr_offset = totsize / channels;
230 
231 	sg = devm_kcalloc(component->dev, sg_num, sizeof(*sg), GFP_KERNEL);
232 	if (!sg) {
233 		ret = -ENOMEM;
234 		goto sg_err;
235 	}
236 
237 	for (i = 0; i < channels; i++) {
238 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
239 		struct dma_chan *chan = data->chan;
240 		struct dma_slave_config config = { };
241 		struct sprd_dma_linklist link = { };
242 		enum dma_transfer_direction dir;
243 		struct scatterlist *sgt = sg;
244 
245 		config.src_maxburst = dma_params->fragment_len[i];
246 		config.src_addr_width = dma_params->datawidth[i];
247 		config.dst_addr_width = dma_params->datawidth[i];
248 		if (is_playback) {
249 			config.src_addr = runtime->dma_addr +
250 				i * dma_private->dma_addr_offset;
251 			config.dst_addr = dma_params->dev_phys[i];
252 			dir = DMA_MEM_TO_DEV;
253 		} else {
254 			config.src_addr = dma_params->dev_phys[i];
255 			config.dst_addr = runtime->dma_addr +
256 				i * dma_private->dma_addr_offset;
257 			dir = DMA_DEV_TO_MEM;
258 		}
259 
260 		sg_init_table(sgt, sg_num);
261 		for (j = 0; j < sg_num; j++, sgt++) {
262 			u32 sg_len = period / channels;
263 
264 			sg_dma_len(sgt) = sg_len;
265 			sg_dma_address(sgt) = runtime->dma_addr +
266 				i * dma_private->dma_addr_offset + sg_len * j;
267 		}
268 
269 		/*
270 		 * Configure the link-list address for the DMA engine link-list
271 		 * mode.
272 		 */
273 		link.virt_addr = (unsigned long)data->virt;
274 		link.phy_addr = data->phys;
275 
276 		ret = dmaengine_slave_config(chan, &config);
277 		if (ret) {
278 			dev_err(component->dev,
279 				"failed to set slave configuration: %d\n", ret);
280 			goto config_err;
281 		}
282 
283 		/*
284 		 * We configure the DMA request mode, interrupt mode, channel
285 		 * mode and channel trigger mode by the flags.
286 		 */
287 		flags = SPRD_DMA_FLAGS(SPRD_DMA_CHN_MODE_NONE, SPRD_DMA_NO_TRG,
288 				       SPRD_DMA_FRAG_REQ, SPRD_DMA_TRANS_INT);
289 		data->desc = chan->device->device_prep_slave_sg(chan, sg,
290 								sg_num, dir,
291 								flags, &link);
292 		if (!data->desc) {
293 			dev_err(component->dev, "failed to prepare slave sg\n");
294 			ret = -ENOMEM;
295 			goto config_err;
296 		}
297 
298 		if (!runtime->no_period_wakeup) {
299 			data->desc->callback = sprd_pcm_dma_complete;
300 			data->desc->callback_param = dma_private;
301 		}
302 	}
303 
304 	devm_kfree(component->dev, sg);
305 
306 	return 0;
307 
308 config_err:
309 	devm_kfree(component->dev, sg);
310 sg_err:
311 	sprd_pcm_release_dma_channel(substream);
312 	return ret;
313 }
314 
315 static int sprd_pcm_hw_free(struct snd_pcm_substream *substream)
316 {
317 	snd_pcm_set_runtime_buffer(substream, NULL);
318 	sprd_pcm_release_dma_channel(substream);
319 
320 	return 0;
321 }
322 
323 static int sprd_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
324 {
325 	struct sprd_pcm_dma_private *dma_private =
326 		substream->runtime->private_data;
327 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
328 	struct snd_soc_component *component =
329 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
330 	int ret = 0, i;
331 
332 	switch (cmd) {
333 	case SNDRV_PCM_TRIGGER_START:
334 		for (i = 0; i < dma_private->hw_chan; i++) {
335 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
336 
337 			if (!data->desc)
338 				continue;
339 
340 			data->cookie = dmaengine_submit(data->desc);
341 			ret = dma_submit_error(data->cookie);
342 			if (ret) {
343 				dev_err(component->dev,
344 					"failed to submit dma request: %d\n",
345 					ret);
346 				return ret;
347 			}
348 
349 			dma_async_issue_pending(data->chan);
350 		}
351 
352 		break;
353 	case SNDRV_PCM_TRIGGER_RESUME:
354 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
355 		for (i = 0; i < dma_private->hw_chan; i++) {
356 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
357 
358 			if (data->chan)
359 				dmaengine_resume(data->chan);
360 		}
361 
362 		break;
363 	case SNDRV_PCM_TRIGGER_STOP:
364 		for (i = 0; i < dma_private->hw_chan; i++) {
365 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
366 
367 			if (data->chan)
368 				dmaengine_terminate_async(data->chan);
369 		}
370 
371 		break;
372 	case SNDRV_PCM_TRIGGER_SUSPEND:
373 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
374 		for (i = 0; i < dma_private->hw_chan; i++) {
375 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
376 
377 			if (data->chan)
378 				dmaengine_pause(data->chan);
379 		}
380 
381 		break;
382 	default:
383 		ret = -EINVAL;
384 	}
385 
386 	return ret;
387 }
388 
389 static snd_pcm_uframes_t sprd_pcm_pointer(struct snd_pcm_substream *substream)
390 {
391 	struct snd_pcm_runtime *runtime = substream->runtime;
392 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
393 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
394 	struct snd_soc_component *component =
395 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
396 	int pointer[SPRD_PCM_CHANNEL_MAX];
397 	int bytes_of_pointer = 0, sel_max = 0, i;
398 	snd_pcm_uframes_t x;
399 	struct dma_tx_state state;
400 	enum dma_status status;
401 
402 	for (i = 0; i < dma_private->hw_chan; i++) {
403 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
404 
405 		if (!data->chan)
406 			continue;
407 
408 		status = dmaengine_tx_status(data->chan, data->cookie, &state);
409 		if (status == DMA_ERROR) {
410 			dev_err(component->dev,
411 				"failed to get dma channel %d status\n", i);
412 			return 0;
413 		}
414 
415 		/*
416 		 * We just get current transfer address from the DMA engine, so
417 		 * we need convert to current pointer.
418 		 */
419 		pointer[i] = state.residue - runtime->dma_addr -
420 			i * dma_private->dma_addr_offset;
421 
422 		if (i == 0) {
423 			bytes_of_pointer = pointer[i];
424 			sel_max = pointer[i] < data->pre_pointer ? 1 : 0;
425 		} else {
426 			sel_max ^= pointer[i] < data->pre_pointer ? 1 : 0;
427 
428 			if (sel_max)
429 				bytes_of_pointer =
430 					max(pointer[i], pointer[i - 1]) << 1;
431 			else
432 				bytes_of_pointer =
433 					min(pointer[i], pointer[i - 1]) << 1;
434 		}
435 
436 		data->pre_pointer = pointer[i];
437 	}
438 
439 	x = bytes_to_frames(runtime, bytes_of_pointer);
440 	if (x == runtime->buffer_size)
441 		x = 0;
442 
443 	return x;
444 }
445 
446 static int sprd_pcm_mmap(struct snd_pcm_substream *substream,
447 			 struct vm_area_struct *vma)
448 {
449 	struct snd_pcm_runtime *runtime = substream->runtime;
450 
451 	vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
452 	return remap_pfn_range(vma, vma->vm_start,
453 			       runtime->dma_addr >> PAGE_SHIFT,
454 			       vma->vm_end - vma->vm_start,
455 			       vma->vm_page_prot);
456 }
457 
458 static struct snd_pcm_ops sprd_pcm_ops = {
459 	.open = sprd_pcm_open,
460 	.close = sprd_pcm_close,
461 	.ioctl = snd_pcm_lib_ioctl,
462 	.hw_params = sprd_pcm_hw_params,
463 	.hw_free = sprd_pcm_hw_free,
464 	.trigger = sprd_pcm_trigger,
465 	.pointer = sprd_pcm_pointer,
466 	.mmap = sprd_pcm_mmap,
467 };
468 
469 static int sprd_pcm_new(struct snd_soc_pcm_runtime *rtd)
470 {
471 	struct snd_card *card = rtd->card->snd_card;
472 	struct snd_pcm *pcm = rtd->pcm;
473 	struct snd_pcm_substream *substream;
474 	int ret;
475 
476 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
477 	if (ret)
478 		return ret;
479 
480 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
481 	if (substream) {
482 		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev,
483 					  sprd_pcm_hardware.buffer_bytes_max,
484 					  &substream->dma_buffer);
485 		if (ret) {
486 			dev_err(card->dev,
487 				"can't alloc playback dma buffer: %d\n", ret);
488 			return ret;
489 		}
490 	}
491 
492 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
493 	if (substream) {
494 		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev,
495 					  sprd_pcm_hardware.buffer_bytes_max,
496 					  &substream->dma_buffer);
497 		if (ret) {
498 			dev_err(card->dev,
499 				"can't alloc capture dma buffer: %d\n", ret);
500 			snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
501 			return ret;
502 		}
503 	}
504 
505 	return 0;
506 }
507 
508 static void sprd_pcm_free(struct snd_pcm *pcm)
509 {
510 	struct snd_pcm_substream *substream;
511 	int i;
512 
513 	for (i = 0; i < ARRAY_SIZE(pcm->streams); i++) {
514 		substream = pcm->streams[i].substream;
515 		if (substream) {
516 			snd_dma_free_pages(&substream->dma_buffer);
517 			substream->dma_buffer.area = NULL;
518 			substream->dma_buffer.addr = 0;
519 		}
520 	}
521 }
522 
523 static const struct snd_soc_component_driver sprd_soc_component = {
524 	.name		= DRV_NAME,
525 	.ops		= &sprd_pcm_ops,
526 	.compr_ops	= &sprd_platform_compr_ops,
527 	.pcm_new	= sprd_pcm_new,
528 	.pcm_free	= sprd_pcm_free,
529 };
530 
531 static int sprd_soc_platform_probe(struct platform_device *pdev)
532 {
533 	int ret;
534 
535 	ret = devm_snd_soc_register_component(&pdev->dev, &sprd_soc_component,
536 					      NULL, 0);
537 	if (ret)
538 		dev_err(&pdev->dev, "could not register platform:%d\n", ret);
539 
540 	return ret;
541 }
542 
543 static const struct of_device_id sprd_pcm_of_match[] = {
544 	{ .compatible = "sprd,pcm-platform", },
545 	{ },
546 };
547 MODULE_DEVICE_TABLE(of, sprd_pcm_of_match);
548 
549 static struct platform_driver sprd_pcm_driver = {
550 	.driver = {
551 		.name = "sprd-pcm-audio",
552 		.of_match_table = sprd_pcm_of_match,
553 	},
554 
555 	.probe = sprd_soc_platform_probe,
556 };
557 
558 module_platform_driver(sprd_pcm_driver);
559 
560 MODULE_DESCRIPTION("Spreadtrum ASoC PCM DMA");
561 MODULE_LICENSE("GPL v2");
562 MODULE_ALIAS("platform:sprd-audio");
563