xref: /openbmc/linux/sound/soc/sprd/sprd-pcm-dma.c (revision ba447289)
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 
sprd_pcm_open(struct snd_soc_component * component,struct snd_pcm_substream * substream)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 
sprd_pcm_close(struct snd_soc_component * component,struct snd_pcm_substream * substream)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 
sprd_pcm_dma_complete(void * data)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 
sprd_pcm_release_dma_channel(struct snd_pcm_substream * substream)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 
sprd_pcm_request_dma_channel(struct snd_soc_component * component,struct snd_pcm_substream * substream,int channels)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 
sprd_pcm_hw_params(struct snd_soc_component * component,struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)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 = asoc_substream_to_rtd(substream);
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 		return 0;
208 	}
209 
210 	if (!dma_private->params) {
211 		dma_private->params = dma_params;
212 		ret = sprd_pcm_request_dma_channel(component,
213 						   substream, channels);
214 		if (ret)
215 			return ret;
216 	}
217 
218 	sg_num = totsize / period;
219 	dma_private->dma_addr_offset = totsize / channels;
220 
221 	sg = devm_kcalloc(component->dev, sg_num, sizeof(*sg), GFP_KERNEL);
222 	if (!sg) {
223 		ret = -ENOMEM;
224 		goto sg_err;
225 	}
226 
227 	for (i = 0; i < channels; i++) {
228 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
229 		struct dma_chan *chan = data->chan;
230 		struct dma_slave_config config = { };
231 		struct sprd_dma_linklist link = { };
232 		enum dma_transfer_direction dir;
233 		struct scatterlist *sgt = sg;
234 
235 		config.src_maxburst = dma_params->fragment_len[i];
236 		config.src_addr_width = dma_params->datawidth[i];
237 		config.dst_addr_width = dma_params->datawidth[i];
238 		if (is_playback) {
239 			config.src_addr = runtime->dma_addr +
240 				i * dma_private->dma_addr_offset;
241 			config.dst_addr = dma_params->dev_phys[i];
242 			dir = DMA_MEM_TO_DEV;
243 		} else {
244 			config.src_addr = dma_params->dev_phys[i];
245 			config.dst_addr = runtime->dma_addr +
246 				i * dma_private->dma_addr_offset;
247 			dir = DMA_DEV_TO_MEM;
248 		}
249 
250 		sg_init_table(sgt, sg_num);
251 		for (j = 0; j < sg_num; j++, sgt++) {
252 			u32 sg_len = period / channels;
253 
254 			sg_dma_len(sgt) = sg_len;
255 			sg_dma_address(sgt) = runtime->dma_addr +
256 				i * dma_private->dma_addr_offset + sg_len * j;
257 		}
258 
259 		/*
260 		 * Configure the link-list address for the DMA engine link-list
261 		 * mode.
262 		 */
263 		link.virt_addr = (unsigned long)data->virt;
264 		link.phy_addr = data->phys;
265 
266 		ret = dmaengine_slave_config(chan, &config);
267 		if (ret) {
268 			dev_err(component->dev,
269 				"failed to set slave configuration: %d\n", ret);
270 			goto config_err;
271 		}
272 
273 		/*
274 		 * We configure the DMA request mode, interrupt mode, channel
275 		 * mode and channel trigger mode by the flags.
276 		 */
277 		flags = SPRD_DMA_FLAGS(SPRD_DMA_CHN_MODE_NONE, SPRD_DMA_NO_TRG,
278 				       SPRD_DMA_FRAG_REQ, SPRD_DMA_TRANS_INT);
279 		data->desc = chan->device->device_prep_slave_sg(chan, sg,
280 								sg_num, dir,
281 								flags, &link);
282 		if (!data->desc) {
283 			dev_err(component->dev, "failed to prepare slave sg\n");
284 			ret = -ENOMEM;
285 			goto config_err;
286 		}
287 
288 		if (!runtime->no_period_wakeup) {
289 			data->desc->callback = sprd_pcm_dma_complete;
290 			data->desc->callback_param = dma_private;
291 		}
292 	}
293 
294 	devm_kfree(component->dev, sg);
295 
296 	return 0;
297 
298 config_err:
299 	devm_kfree(component->dev, sg);
300 sg_err:
301 	sprd_pcm_release_dma_channel(substream);
302 	return ret;
303 }
304 
sprd_pcm_hw_free(struct snd_soc_component * component,struct snd_pcm_substream * substream)305 static int sprd_pcm_hw_free(struct snd_soc_component *component,
306 			    struct snd_pcm_substream *substream)
307 {
308 	sprd_pcm_release_dma_channel(substream);
309 
310 	return 0;
311 }
312 
sprd_pcm_trigger(struct snd_soc_component * component,struct snd_pcm_substream * substream,int cmd)313 static int sprd_pcm_trigger(struct snd_soc_component *component,
314 			    struct snd_pcm_substream *substream, int cmd)
315 {
316 	struct sprd_pcm_dma_private *dma_private =
317 		substream->runtime->private_data;
318 	int ret = 0, i;
319 
320 	switch (cmd) {
321 	case SNDRV_PCM_TRIGGER_START:
322 		for (i = 0; i < dma_private->hw_chan; i++) {
323 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
324 
325 			if (!data->desc)
326 				continue;
327 
328 			data->cookie = dmaengine_submit(data->desc);
329 			ret = dma_submit_error(data->cookie);
330 			if (ret) {
331 				dev_err(component->dev,
332 					"failed to submit dma request: %d\n",
333 					ret);
334 				return ret;
335 			}
336 
337 			dma_async_issue_pending(data->chan);
338 		}
339 
340 		break;
341 	case SNDRV_PCM_TRIGGER_RESUME:
342 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
343 		for (i = 0; i < dma_private->hw_chan; i++) {
344 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
345 
346 			if (data->chan)
347 				dmaengine_resume(data->chan);
348 		}
349 
350 		break;
351 	case SNDRV_PCM_TRIGGER_STOP:
352 		for (i = 0; i < dma_private->hw_chan; i++) {
353 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
354 
355 			if (data->chan)
356 				dmaengine_terminate_async(data->chan);
357 		}
358 
359 		break;
360 	case SNDRV_PCM_TRIGGER_SUSPEND:
361 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
362 		for (i = 0; i < dma_private->hw_chan; i++) {
363 			struct sprd_pcm_dma_data *data = &dma_private->data[i];
364 
365 			if (data->chan)
366 				dmaengine_pause(data->chan);
367 		}
368 
369 		break;
370 	default:
371 		ret = -EINVAL;
372 	}
373 
374 	return ret;
375 }
376 
sprd_pcm_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)377 static snd_pcm_uframes_t sprd_pcm_pointer(struct snd_soc_component *component,
378 					  struct snd_pcm_substream *substream)
379 {
380 	struct snd_pcm_runtime *runtime = substream->runtime;
381 	struct sprd_pcm_dma_private *dma_private = runtime->private_data;
382 	int pointer[SPRD_PCM_CHANNEL_MAX];
383 	int bytes_of_pointer = 0, sel_max = 0, i;
384 	snd_pcm_uframes_t x;
385 	struct dma_tx_state state;
386 	enum dma_status status;
387 
388 	for (i = 0; i < dma_private->hw_chan; i++) {
389 		struct sprd_pcm_dma_data *data = &dma_private->data[i];
390 
391 		if (!data->chan)
392 			continue;
393 
394 		status = dmaengine_tx_status(data->chan, data->cookie, &state);
395 		if (status == DMA_ERROR) {
396 			dev_err(component->dev,
397 				"failed to get dma channel %d status\n", i);
398 			return 0;
399 		}
400 
401 		/*
402 		 * We just get current transfer address from the DMA engine, so
403 		 * we need convert to current pointer.
404 		 */
405 		pointer[i] = state.residue - runtime->dma_addr -
406 			i * dma_private->dma_addr_offset;
407 
408 		if (i == 0) {
409 			bytes_of_pointer = pointer[i];
410 			sel_max = pointer[i] < data->pre_pointer ? 1 : 0;
411 		} else {
412 			sel_max ^= pointer[i] < data->pre_pointer ? 1 : 0;
413 
414 			if (sel_max)
415 				bytes_of_pointer =
416 					max(pointer[i], pointer[i - 1]) << 1;
417 			else
418 				bytes_of_pointer =
419 					min(pointer[i], pointer[i - 1]) << 1;
420 		}
421 
422 		data->pre_pointer = pointer[i];
423 	}
424 
425 	x = bytes_to_frames(runtime, bytes_of_pointer);
426 	if (x == runtime->buffer_size)
427 		x = 0;
428 
429 	return x;
430 }
431 
sprd_pcm_new(struct snd_soc_component * component,struct snd_soc_pcm_runtime * rtd)432 static int sprd_pcm_new(struct snd_soc_component *component,
433 			struct snd_soc_pcm_runtime *rtd)
434 {
435 	struct snd_card *card = rtd->card->snd_card;
436 	struct snd_pcm *pcm = rtd->pcm;
437 	int ret;
438 
439 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
440 	if (ret)
441 		return ret;
442 
443 	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
444 					    card->dev,
445 					    sprd_pcm_hardware.buffer_bytes_max);
446 }
447 
448 static const struct snd_soc_component_driver sprd_soc_component = {
449 	.name		= DRV_NAME,
450 	.open		= sprd_pcm_open,
451 	.close		= sprd_pcm_close,
452 	.hw_params	= sprd_pcm_hw_params,
453 	.hw_free	= sprd_pcm_hw_free,
454 	.trigger	= sprd_pcm_trigger,
455 	.pointer	= sprd_pcm_pointer,
456 	.pcm_construct	= sprd_pcm_new,
457 	.compress_ops	= &sprd_platform_compress_ops,
458 };
459 
sprd_soc_platform_probe(struct platform_device * pdev)460 static int sprd_soc_platform_probe(struct platform_device *pdev)
461 {
462 	struct device_node *np = pdev->dev.of_node;
463 	int ret;
464 
465 	ret = of_reserved_mem_device_init_by_idx(&pdev->dev, np, 0);
466 	if (ret)
467 		dev_warn(&pdev->dev,
468 			 "no reserved DMA memory for audio platform device\n");
469 
470 	ret = devm_snd_soc_register_component(&pdev->dev, &sprd_soc_component,
471 					      NULL, 0);
472 	if (ret)
473 		dev_err(&pdev->dev, "could not register platform:%d\n", ret);
474 
475 	return ret;
476 }
477 
478 static const struct of_device_id sprd_pcm_of_match[] = {
479 	{ .compatible = "sprd,pcm-platform", },
480 	{ },
481 };
482 MODULE_DEVICE_TABLE(of, sprd_pcm_of_match);
483 
484 static struct platform_driver sprd_pcm_driver = {
485 	.driver = {
486 		.name = "sprd-pcm-audio",
487 		.of_match_table = sprd_pcm_of_match,
488 	},
489 
490 	.probe = sprd_soc_platform_probe,
491 };
492 
493 module_platform_driver(sprd_pcm_driver);
494 
495 MODULE_DESCRIPTION("Spreadtrum ASoC PCM DMA");
496 MODULE_LICENSE("GPL v2");
497 MODULE_ALIAS("platform:sprd-audio");
498