xref: /openbmc/linux/sound/soc/sprd/sprd-pcm-dma.c (revision 22d55f02)
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_pcm_substream *substream)
50 {
51 	struct snd_pcm_runtime *runtime = substream->runtime;
52 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
53 	struct snd_soc_component *component =
54 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
55 	struct device *dev = component->dev;
56 	struct sprd_pcm_dma_private *dma_private;
57 	int hw_chan = SPRD_PCM_CHANNEL_MAX;
58 	int size, ret, i;
59 
60 	snd_soc_set_runtime_hwparams(substream, &sprd_pcm_hardware);
61 
62 	ret = snd_pcm_hw_constraint_step(runtime, 0,
63 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
64 					 SPRD_PCM_DMA_BRUST_LEN);
65 	if (ret < 0)
66 		return ret;
67 
68 	ret = snd_pcm_hw_constraint_step(runtime, 0,
69 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
70 					 SPRD_PCM_DMA_BRUST_LEN);
71 	if (ret < 0)
72 		return ret;
73 
74 	ret = snd_pcm_hw_constraint_integer(runtime,
75 					    SNDRV_PCM_HW_PARAM_PERIODS);
76 	if (ret < 0)
77 		return ret;
78 
79 	dma_private = devm_kzalloc(dev, sizeof(*dma_private), GFP_KERNEL);
80 	if (!dma_private)
81 		return -ENOMEM;
82 
83 	size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
84 
85 	for (i = 0; i < hw_chan; i++) {
86 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
87 
88 		data->virt = dmam_alloc_coherent(dev, size, &data->phys,
89 						 GFP_KERNEL);
90 		if (!data->virt) {
91 			ret = -ENOMEM;
92 			goto error;
93 		}
94 	}
95 
96 	dma_private->hw_chan = hw_chan;
97 	runtime->private_data = dma_private;
98 	dma_private->substream = substream;
99 
100 	return 0;
101 
102 error:
103 	for (i = 0; i < hw_chan; i++) {
104 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
105 
106 		if (data->virt)
107 			dmam_free_coherent(dev, size, data->virt, data->phys);
108 	}
109 
110 	devm_kfree(dev, dma_private);
111 	return ret;
112 }
113 
114 static int sprd_pcm_close(struct snd_pcm_substream *substream)
115 {
116 	struct snd_pcm_runtime *runtime = substream->runtime;
117 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
118 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
119 	struct snd_soc_component *component =
120 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
121 	struct device *dev = component->dev;
122 	int size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
123 	int i;
124 
125 	for (i = 0; i < dma_private->hw_chan; i++) {
126 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
127 
128 		dmam_free_coherent(dev, size, data->virt, data->phys);
129 	}
130 
131 	devm_kfree(dev, dma_private);
132 
133 	return 0;
134 }
135 
136 static void sprd_pcm_dma_complete(void *data)
137 {
138 	struct sprd_pcm_dma_private *dma_private = data;
139 	struct snd_pcm_substream *substream = dma_private->substream;
140 
141 	snd_pcm_period_elapsed(substream);
142 }
143 
144 static void sprd_pcm_release_dma_channel(struct snd_pcm_substream *substream)
145 {
146 	struct snd_pcm_runtime *runtime = substream->runtime;
147 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
148 	int i;
149 
150 	for (i = 0; i < SPRD_PCM_CHANNEL_MAX; i++) {
151 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
152 
153 		if (data->chan) {
154 			dma_release_channel(data->chan);
155 			data->chan = NULL;
156 		}
157 	}
158 }
159 
160 static int sprd_pcm_request_dma_channel(struct snd_pcm_substream *substream,
161 					int channels)
162 {
163 	struct snd_pcm_runtime *runtime = substream->runtime;
164 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
165 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
166 	struct snd_soc_component *component =
167 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
168 	struct device *dev = component->dev;
169 	struct sprd_pcm_dma_params *dma_params = dma_private->params;
170 	int i;
171 
172 	if (channels > SPRD_PCM_CHANNEL_MAX) {
173 		dev_err(dev, "invalid dma channel number:%d\n", channels);
174 		return -EINVAL;
175 	}
176 
177 	for (i = 0; i < channels; i++) {
178 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
179 
180 		data->chan = dma_request_slave_channel(dev,
181 						       dma_params->chan_name[i]);
182 		if (!data->chan) {
183 			dev_err(dev, "failed to request dma channel:%s\n",
184 				dma_params->chan_name[i]);
185 			sprd_pcm_release_dma_channel(substream);
186 			return -ENODEV;
187 		}
188 	}
189 
190 	return 0;
191 }
192 
193 static int sprd_pcm_hw_params(struct snd_pcm_substream *substream,
194 			      struct snd_pcm_hw_params *params)
195 {
196 	struct snd_pcm_runtime *runtime = substream->runtime;
197 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
198 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
199 	struct snd_soc_component *component =
200 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
201 	struct sprd_pcm_dma_params *dma_params;
202 	size_t totsize = params_buffer_bytes(params);
203 	size_t period = params_period_bytes(params);
204 	int channels = params_channels(params);
205 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
206 	struct scatterlist *sg;
207 	unsigned long flags;
208 	int ret, i, j, sg_num;
209 
210 	dma_params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
211 	if (!dma_params) {
212 		dev_warn(component->dev, "no dma parameters setting\n");
213 		dma_private->params = NULL;
214 		snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
215 		runtime->dma_bytes = totsize;
216 		return 0;
217 	}
218 
219 	if (!dma_private->params) {
220 		dma_private->params = dma_params;
221 		ret = sprd_pcm_request_dma_channel(substream, channels);
222 		if (ret)
223 			return ret;
224 	}
225 
226 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
227 
228 	runtime->dma_bytes = totsize;
229 	sg_num = totsize / period;
230 	dma_private->dma_addr_offset = totsize / channels;
231 
232 	sg = devm_kcalloc(component->dev, sg_num, sizeof(*sg), GFP_KERNEL);
233 	if (!sg) {
234 		ret = -ENOMEM;
235 		goto sg_err;
236 	}
237 
238 	for (i = 0; i < channels; i++) {
239 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
240 		struct dma_chan *chan = data->chan;
241 		struct dma_slave_config config = { };
242 		struct sprd_dma_linklist link = { };
243 		enum dma_transfer_direction dir;
244 		struct scatterlist *sgt = sg;
245 
246 		config.src_maxburst = dma_params->fragment_len[i];
247 		config.src_addr_width = dma_params->datawidth[i];
248 		config.dst_addr_width = dma_params->datawidth[i];
249 		if (is_playback) {
250 			config.src_addr = runtime->dma_addr +
251 				i * dma_private->dma_addr_offset;
252 			config.dst_addr = dma_params->dev_phys[i];
253 			dir = DMA_MEM_TO_DEV;
254 		} else {
255 			config.src_addr = dma_params->dev_phys[i];
256 			config.dst_addr = runtime->dma_addr +
257 				i * dma_private->dma_addr_offset;
258 			dir = DMA_DEV_TO_MEM;
259 		}
260 
261 		sg_init_table(sgt, sg_num);
262 		for (j = 0; j < sg_num; j++, sgt++) {
263 			u32 sg_len = period / channels;
264 
265 			sg_dma_len(sgt) = sg_len;
266 			sg_dma_address(sgt) = runtime->dma_addr +
267 				i * dma_private->dma_addr_offset + sg_len * j;
268 		}
269 
270 		/*
271 		 * Configure the link-list address for the DMA engine link-list
272 		 * mode.
273 		 */
274 		link.virt_addr = (unsigned long)data->virt;
275 		link.phy_addr = data->phys;
276 
277 		ret = dmaengine_slave_config(chan, &config);
278 		if (ret) {
279 			dev_err(component->dev,
280 				"failed to set slave configuration: %d\n", ret);
281 			goto config_err;
282 		}
283 
284 		/*
285 		 * We configure the DMA request mode, interrupt mode, channel
286 		 * mode and channel trigger mode by the flags.
287 		 */
288 		flags = SPRD_DMA_FLAGS(SPRD_DMA_CHN_MODE_NONE, SPRD_DMA_NO_TRG,
289 				       SPRD_DMA_FRAG_REQ, SPRD_DMA_TRANS_INT);
290 		data->desc = chan->device->device_prep_slave_sg(chan, sg,
291 								sg_num, dir,
292 								flags, &link);
293 		if (!data->desc) {
294 			dev_err(component->dev, "failed to prepare slave sg\n");
295 			ret = -ENOMEM;
296 			goto config_err;
297 		}
298 
299 		if (!runtime->no_period_wakeup) {
300 			data->desc->callback = sprd_pcm_dma_complete;
301 			data->desc->callback_param = dma_private;
302 		}
303 	}
304 
305 	devm_kfree(component->dev, sg);
306 
307 	return 0;
308 
309 config_err:
310 	devm_kfree(component->dev, sg);
311 sg_err:
312 	sprd_pcm_release_dma_channel(substream);
313 	return ret;
314 }
315 
316 static int sprd_pcm_hw_free(struct snd_pcm_substream *substream)
317 {
318 	snd_pcm_set_runtime_buffer(substream, NULL);
319 	sprd_pcm_release_dma_channel(substream);
320 
321 	return 0;
322 }
323 
324 static int sprd_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
325 {
326 	struct sprd_pcm_dma_private *dma_private =
327 		substream->runtime->private_data;
328 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
329 	struct snd_soc_component *component =
330 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
331 	int ret = 0, i;
332 
333 	switch (cmd) {
334 	case SNDRV_PCM_TRIGGER_START:
335 		for (i = 0; i < dma_private->hw_chan; i++) {
336 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
337 
338 			if (!data->desc)
339 				continue;
340 
341 			data->cookie = dmaengine_submit(data->desc);
342 			ret = dma_submit_error(data->cookie);
343 			if (ret) {
344 				dev_err(component->dev,
345 					"failed to submit dma request: %d\n",
346 					ret);
347 				return ret;
348 			}
349 
350 			dma_async_issue_pending(data->chan);
351 		}
352 
353 		break;
354 	case SNDRV_PCM_TRIGGER_RESUME:
355 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
356 		for (i = 0; i < dma_private->hw_chan; i++) {
357 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
358 
359 			if (data->chan)
360 				dmaengine_resume(data->chan);
361 		}
362 
363 		break;
364 	case SNDRV_PCM_TRIGGER_STOP:
365 		for (i = 0; i < dma_private->hw_chan; i++) {
366 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
367 
368 			if (data->chan)
369 				dmaengine_terminate_async(data->chan);
370 		}
371 
372 		break;
373 	case SNDRV_PCM_TRIGGER_SUSPEND:
374 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
375 		for (i = 0; i < dma_private->hw_chan; i++) {
376 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
377 
378 			if (data->chan)
379 				dmaengine_pause(data->chan);
380 		}
381 
382 		break;
383 	default:
384 		ret = -EINVAL;
385 	}
386 
387 	return ret;
388 }
389 
390 static snd_pcm_uframes_t sprd_pcm_pointer(struct snd_pcm_substream *substream)
391 {
392 	struct snd_pcm_runtime *runtime = substream->runtime;
393 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
394 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
395 	struct snd_soc_component *component =
396 		snd_soc_rtdcom_lookup(rtd, DRV_NAME);
397 	int pointer[SPRD_PCM_CHANNEL_MAX];
398 	int bytes_of_pointer = 0, sel_max = 0, i;
399 	snd_pcm_uframes_t x;
400 	struct dma_tx_state state;
401 	enum dma_status status;
402 
403 	for (i = 0; i < dma_private->hw_chan; i++) {
404 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
405 
406 		if (!data->chan)
407 			continue;
408 
409 		status = dmaengine_tx_status(data->chan, data->cookie, &state);
410 		if (status == DMA_ERROR) {
411 			dev_err(component->dev,
412 				"failed to get dma channel %d status\n", i);
413 			return 0;
414 		}
415 
416 		/*
417 		 * We just get current transfer address from the DMA engine, so
418 		 * we need convert to current pointer.
419 		 */
420 		pointer[i] = state.residue - runtime->dma_addr -
421 			i * dma_private->dma_addr_offset;
422 
423 		if (i == 0) {
424 			bytes_of_pointer = pointer[i];
425 			sel_max = pointer[i] < data->pre_pointer ? 1 : 0;
426 		} else {
427 			sel_max ^= pointer[i] < data->pre_pointer ? 1 : 0;
428 
429 			if (sel_max)
430 				bytes_of_pointer =
431 					max(pointer[i], pointer[i - 1]) << 1;
432 			else
433 				bytes_of_pointer =
434 					min(pointer[i], pointer[i - 1]) << 1;
435 		}
436 
437 		data->pre_pointer = pointer[i];
438 	}
439 
440 	x = bytes_to_frames(runtime, bytes_of_pointer);
441 	if (x == runtime->buffer_size)
442 		x = 0;
443 
444 	return x;
445 }
446 
447 static int sprd_pcm_mmap(struct snd_pcm_substream *substream,
448 			 struct vm_area_struct *vma)
449 {
450 	struct snd_pcm_runtime *runtime = substream->runtime;
451 
452 	vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
453 	return remap_pfn_range(vma, vma->vm_start,
454 			       runtime->dma_addr >> PAGE_SHIFT,
455 			       vma->vm_end - vma->vm_start,
456 			       vma->vm_page_prot);
457 }
458 
459 static struct snd_pcm_ops sprd_pcm_ops = {
460 	.open = sprd_pcm_open,
461 	.close = sprd_pcm_close,
462 	.ioctl = snd_pcm_lib_ioctl,
463 	.hw_params = sprd_pcm_hw_params,
464 	.hw_free = sprd_pcm_hw_free,
465 	.trigger = sprd_pcm_trigger,
466 	.pointer = sprd_pcm_pointer,
467 	.mmap = sprd_pcm_mmap,
468 };
469 
470 static int sprd_pcm_new(struct snd_soc_pcm_runtime *rtd)
471 {
472 	struct snd_card *card = rtd->card->snd_card;
473 	struct snd_pcm *pcm = rtd->pcm;
474 	struct snd_pcm_substream *substream;
475 	int ret;
476 
477 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
478 	if (ret)
479 		return ret;
480 
481 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
482 	if (substream) {
483 		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev,
484 					  sprd_pcm_hardware.buffer_bytes_max,
485 					  &substream->dma_buffer);
486 		if (ret) {
487 			dev_err(card->dev,
488 				"can't alloc playback dma buffer: %d\n", ret);
489 			return ret;
490 		}
491 	}
492 
493 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
494 	if (substream) {
495 		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev,
496 					  sprd_pcm_hardware.buffer_bytes_max,
497 					  &substream->dma_buffer);
498 		if (ret) {
499 			dev_err(card->dev,
500 				"can't alloc capture dma buffer: %d\n", ret);
501 			snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
502 			return ret;
503 		}
504 	}
505 
506 	return 0;
507 }
508 
509 static void sprd_pcm_free(struct snd_pcm *pcm)
510 {
511 	struct snd_pcm_substream *substream;
512 	int i;
513 
514 	for (i = 0; i < ARRAY_SIZE(pcm->streams); i++) {
515 		substream = pcm->streams[i].substream;
516 		if (substream) {
517 			snd_dma_free_pages(&substream->dma_buffer);
518 			substream->dma_buffer.area = NULL;
519 			substream->dma_buffer.addr = 0;
520 		}
521 	}
522 }
523 
524 static const struct snd_soc_component_driver sprd_soc_component = {
525 	.name		= DRV_NAME,
526 	.ops		= &sprd_pcm_ops,
527 	.compr_ops	= &sprd_platform_compr_ops,
528 	.pcm_new	= sprd_pcm_new,
529 	.pcm_free	= sprd_pcm_free,
530 };
531 
532 static int sprd_soc_platform_probe(struct platform_device *pdev)
533 {
534 	struct device_node *np = pdev->dev.of_node;
535 	int ret;
536 
537 	ret = of_reserved_mem_device_init_by_idx(&pdev->dev, np, 0);
538 	if (ret)
539 		dev_warn(&pdev->dev,
540 			 "no reserved DMA memory for audio platform device\n");
541 
542 	ret = devm_snd_soc_register_component(&pdev->dev, &sprd_soc_component,
543 					      NULL, 0);
544 	if (ret)
545 		dev_err(&pdev->dev, "could not register platform:%d\n", ret);
546 
547 	return ret;
548 }
549 
550 static const struct of_device_id sprd_pcm_of_match[] = {
551 	{ .compatible = "sprd,pcm-platform", },
552 	{ },
553 };
554 MODULE_DEVICE_TABLE(of, sprd_pcm_of_match);
555 
556 static struct platform_driver sprd_pcm_driver = {
557 	.driver = {
558 		.name = "sprd-pcm-audio",
559 		.of_match_table = sprd_pcm_of_match,
560 	},
561 
562 	.probe = sprd_soc_platform_probe,
563 };
564 
565 module_platform_driver(sprd_pcm_driver);
566 
567 MODULE_DESCRIPTION("Spreadtrum ASoC PCM DMA");
568 MODULE_LICENSE("GPL v2");
569 MODULE_ALIAS("platform:sprd-audio");
570