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1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Freescale ASRC ALSA SoC Platform (DMA) driver
4 //
5 // Copyright (C) 2014 Freescale Semiconductor, Inc.
6 //
7 // Author: Nicolin Chen <nicoleotsuka@gmail.com>
8 
9 #include <linux/dma-mapping.h>
10 #include <linux/module.h>
11 #include <linux/platform_data/dma-imx.h>
12 #include <sound/dmaengine_pcm.h>
13 #include <sound/pcm_params.h>
14 
15 #include "fsl_asrc_common.h"
16 
17 #define FSL_ASRC_DMABUF_SIZE	(256 * 1024)
18 
19 static struct snd_pcm_hardware snd_imx_hardware = {
20 	.info = SNDRV_PCM_INFO_INTERLEAVED |
21 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
22 		SNDRV_PCM_INFO_MMAP |
23 		SNDRV_PCM_INFO_MMAP_VALID,
24 	.buffer_bytes_max = FSL_ASRC_DMABUF_SIZE,
25 	.period_bytes_min = 128,
26 	.period_bytes_max = 65535, /* Limited by SDMA engine */
27 	.periods_min = 2,
28 	.periods_max = 255,
29 	.fifo_size = 0,
30 };
31 
filter(struct dma_chan * chan,void * param)32 static bool filter(struct dma_chan *chan, void *param)
33 {
34 	if (!imx_dma_is_general_purpose(chan))
35 		return false;
36 
37 	chan->private = param;
38 
39 	return true;
40 }
41 
fsl_asrc_dma_complete(void * arg)42 static void fsl_asrc_dma_complete(void *arg)
43 {
44 	struct snd_pcm_substream *substream = arg;
45 	struct snd_pcm_runtime *runtime = substream->runtime;
46 	struct fsl_asrc_pair *pair = runtime->private_data;
47 
48 	pair->pos += snd_pcm_lib_period_bytes(substream);
49 	if (pair->pos >= snd_pcm_lib_buffer_bytes(substream))
50 		pair->pos = 0;
51 
52 	snd_pcm_period_elapsed(substream);
53 }
54 
fsl_asrc_dma_prepare_and_submit(struct snd_pcm_substream * substream,struct snd_soc_component * component)55 static int fsl_asrc_dma_prepare_and_submit(struct snd_pcm_substream *substream,
56 					   struct snd_soc_component *component)
57 {
58 	u8 dir = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? OUT : IN;
59 	struct snd_pcm_runtime *runtime = substream->runtime;
60 	struct fsl_asrc_pair *pair = runtime->private_data;
61 	struct device *dev = component->dev;
62 	unsigned long flags = DMA_CTRL_ACK;
63 
64 	/* Prepare and submit Front-End DMA channel */
65 	if (!substream->runtime->no_period_wakeup)
66 		flags |= DMA_PREP_INTERRUPT;
67 
68 	pair->pos = 0;
69 	pair->desc[!dir] = dmaengine_prep_dma_cyclic(
70 			pair->dma_chan[!dir], runtime->dma_addr,
71 			snd_pcm_lib_buffer_bytes(substream),
72 			snd_pcm_lib_period_bytes(substream),
73 			dir == OUT ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM, flags);
74 	if (!pair->desc[!dir]) {
75 		dev_err(dev, "failed to prepare slave DMA for Front-End\n");
76 		return -ENOMEM;
77 	}
78 
79 	pair->desc[!dir]->callback = fsl_asrc_dma_complete;
80 	pair->desc[!dir]->callback_param = substream;
81 
82 	dmaengine_submit(pair->desc[!dir]);
83 
84 	/* Prepare and submit Back-End DMA channel */
85 	pair->desc[dir] = dmaengine_prep_dma_cyclic(
86 			pair->dma_chan[dir], 0xffff, 64, 64, DMA_DEV_TO_DEV, 0);
87 	if (!pair->desc[dir]) {
88 		dev_err(dev, "failed to prepare slave DMA for Back-End\n");
89 		return -ENOMEM;
90 	}
91 
92 	dmaengine_submit(pair->desc[dir]);
93 
94 	return 0;
95 }
96 
fsl_asrc_dma_trigger(struct snd_soc_component * component,struct snd_pcm_substream * substream,int cmd)97 static int fsl_asrc_dma_trigger(struct snd_soc_component *component,
98 				struct snd_pcm_substream *substream, int cmd)
99 {
100 	struct snd_pcm_runtime *runtime = substream->runtime;
101 	struct fsl_asrc_pair *pair = runtime->private_data;
102 	int ret;
103 
104 	switch (cmd) {
105 	case SNDRV_PCM_TRIGGER_START:
106 	case SNDRV_PCM_TRIGGER_RESUME:
107 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
108 		ret = fsl_asrc_dma_prepare_and_submit(substream, component);
109 		if (ret)
110 			return ret;
111 		dma_async_issue_pending(pair->dma_chan[IN]);
112 		dma_async_issue_pending(pair->dma_chan[OUT]);
113 		break;
114 	case SNDRV_PCM_TRIGGER_STOP:
115 	case SNDRV_PCM_TRIGGER_SUSPEND:
116 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
117 		dmaengine_terminate_all(pair->dma_chan[OUT]);
118 		dmaengine_terminate_all(pair->dma_chan[IN]);
119 		break;
120 	default:
121 		return -EINVAL;
122 	}
123 
124 	return 0;
125 }
126 
fsl_asrc_dma_hw_params(struct snd_soc_component * component,struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)127 static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
128 				  struct snd_pcm_substream *substream,
129 				  struct snd_pcm_hw_params *params)
130 {
131 	enum dma_slave_buswidth buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
132 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
133 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
134 	struct snd_dmaengine_dai_dma_data *dma_params_fe = NULL;
135 	struct snd_dmaengine_dai_dma_data *dma_params_be = NULL;
136 	struct snd_pcm_runtime *runtime = substream->runtime;
137 	struct fsl_asrc_pair *pair = runtime->private_data;
138 	struct dma_chan *tmp_chan = NULL, *be_chan = NULL;
139 	struct snd_soc_component *component_be = NULL;
140 	struct fsl_asrc *asrc = pair->asrc;
141 	struct dma_slave_config config_fe, config_be;
142 	enum asrc_pair_index index = pair->index;
143 	struct device *dev = component->dev;
144 	int stream = substream->stream;
145 	struct imx_dma_data *tmp_data;
146 	struct snd_soc_dpcm *dpcm;
147 	struct device *dev_be;
148 	u8 dir = tx ? OUT : IN;
149 	dma_cap_mask_t mask;
150 	int ret, width;
151 
152 	/* Fetch the Back-End dma_data from DPCM */
153 	for_each_dpcm_be(rtd, stream, dpcm) {
154 		struct snd_soc_pcm_runtime *be = dpcm->be;
155 		struct snd_pcm_substream *substream_be;
156 		struct snd_soc_dai *dai = asoc_rtd_to_cpu(be, 0);
157 
158 		if (dpcm->fe != rtd)
159 			continue;
160 
161 		substream_be = snd_soc_dpcm_get_substream(be, stream);
162 		dma_params_be = snd_soc_dai_get_dma_data(dai, substream_be);
163 		dev_be = dai->dev;
164 		break;
165 	}
166 
167 	if (!dma_params_be) {
168 		dev_err(dev, "failed to get the substream of Back-End\n");
169 		return -EINVAL;
170 	}
171 
172 	/* Override dma_data of the Front-End and config its dmaengine */
173 	dma_params_fe = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
174 	dma_params_fe->addr = asrc->paddr + asrc->get_fifo_addr(!dir, index);
175 	dma_params_fe->maxburst = dma_params_be->maxburst;
176 
177 	pair->dma_chan[!dir] = asrc->get_dma_channel(pair, !dir);
178 	if (!pair->dma_chan[!dir]) {
179 		dev_err(dev, "failed to request DMA channel\n");
180 		return -EINVAL;
181 	}
182 
183 	memset(&config_fe, 0, sizeof(config_fe));
184 	ret = snd_dmaengine_pcm_prepare_slave_config(substream, params, &config_fe);
185 	if (ret) {
186 		dev_err(dev, "failed to prepare DMA config for Front-End\n");
187 		return ret;
188 	}
189 
190 	ret = dmaengine_slave_config(pair->dma_chan[!dir], &config_fe);
191 	if (ret) {
192 		dev_err(dev, "failed to config DMA channel for Front-End\n");
193 		return ret;
194 	}
195 
196 	/* Request and config DMA channel for Back-End */
197 	dma_cap_zero(mask);
198 	dma_cap_set(DMA_SLAVE, mask);
199 	dma_cap_set(DMA_CYCLIC, mask);
200 
201 	/*
202 	 * The Back-End device might have already requested a DMA channel,
203 	 * so try to reuse it first, and then request a new one upon NULL.
204 	 */
205 	component_be = snd_soc_lookup_component_nolocked(dev_be, SND_DMAENGINE_PCM_DRV_NAME);
206 	if (component_be) {
207 		be_chan = soc_component_to_pcm(component_be)->chan[substream->stream];
208 		tmp_chan = be_chan;
209 	}
210 	if (!tmp_chan) {
211 		tmp_chan = dma_request_chan(dev_be, tx ? "tx" : "rx");
212 		if (IS_ERR(tmp_chan)) {
213 			dev_err(dev, "failed to request DMA channel for Back-End\n");
214 			return -EINVAL;
215 		}
216 	}
217 
218 	/*
219 	 * An EDMA DEV_TO_DEV channel is fixed and bound with DMA event of each
220 	 * peripheral, unlike SDMA channel that is allocated dynamically. So no
221 	 * need to configure dma_request and dma_request2, but get dma_chan of
222 	 * Back-End device directly via dma_request_chan.
223 	 */
224 	if (!asrc->use_edma) {
225 		/* Get DMA request of Back-End */
226 		tmp_data = tmp_chan->private;
227 		pair->dma_data.dma_request = tmp_data->dma_request;
228 		if (!be_chan)
229 			dma_release_channel(tmp_chan);
230 
231 		/* Get DMA request of Front-End */
232 		tmp_chan = asrc->get_dma_channel(pair, dir);
233 		tmp_data = tmp_chan->private;
234 		pair->dma_data.dma_request2 = tmp_data->dma_request;
235 		pair->dma_data.peripheral_type = tmp_data->peripheral_type;
236 		pair->dma_data.priority = tmp_data->priority;
237 		dma_release_channel(tmp_chan);
238 
239 		pair->dma_chan[dir] =
240 			dma_request_channel(mask, filter, &pair->dma_data);
241 		pair->req_dma_chan = true;
242 	} else {
243 		pair->dma_chan[dir] = tmp_chan;
244 		/* Do not flag to release if we are reusing the Back-End one */
245 		pair->req_dma_chan = !be_chan;
246 	}
247 
248 	if (!pair->dma_chan[dir]) {
249 		dev_err(dev, "failed to request DMA channel for Back-End\n");
250 		return -EINVAL;
251 	}
252 
253 	width = snd_pcm_format_physical_width(asrc->asrc_format);
254 	if (width < 8 || width > 64)
255 		return -EINVAL;
256 	else if (width == 8)
257 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
258 	else if (width == 16)
259 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
260 	else if (width == 24)
261 		buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
262 	else if (width <= 32)
263 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
264 	else
265 		buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
266 
267 	config_be.direction = DMA_DEV_TO_DEV;
268 	config_be.src_addr_width = buswidth;
269 	config_be.src_maxburst = dma_params_be->maxburst;
270 	config_be.dst_addr_width = buswidth;
271 	config_be.dst_maxburst = dma_params_be->maxburst;
272 
273 	if (tx) {
274 		config_be.src_addr = asrc->paddr + asrc->get_fifo_addr(OUT, index);
275 		config_be.dst_addr = dma_params_be->addr;
276 	} else {
277 		config_be.dst_addr = asrc->paddr + asrc->get_fifo_addr(IN, index);
278 		config_be.src_addr = dma_params_be->addr;
279 	}
280 
281 	ret = dmaengine_slave_config(pair->dma_chan[dir], &config_be);
282 	if (ret) {
283 		dev_err(dev, "failed to config DMA channel for Back-End\n");
284 		if (pair->req_dma_chan)
285 			dma_release_channel(pair->dma_chan[dir]);
286 		return ret;
287 	}
288 
289 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
290 
291 	return 0;
292 }
293 
fsl_asrc_dma_hw_free(struct snd_soc_component * component,struct snd_pcm_substream * substream)294 static int fsl_asrc_dma_hw_free(struct snd_soc_component *component,
295 				struct snd_pcm_substream *substream)
296 {
297 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
298 	struct snd_pcm_runtime *runtime = substream->runtime;
299 	struct fsl_asrc_pair *pair = runtime->private_data;
300 	u8 dir = tx ? OUT : IN;
301 
302 	snd_pcm_set_runtime_buffer(substream, NULL);
303 
304 	if (pair->dma_chan[!dir])
305 		dma_release_channel(pair->dma_chan[!dir]);
306 
307 	/* release dev_to_dev chan if we aren't reusing the Back-End one */
308 	if (pair->dma_chan[dir] && pair->req_dma_chan)
309 		dma_release_channel(pair->dma_chan[dir]);
310 
311 	pair->dma_chan[!dir] = NULL;
312 	pair->dma_chan[dir] = NULL;
313 
314 	return 0;
315 }
316 
fsl_asrc_dma_startup(struct snd_soc_component * component,struct snd_pcm_substream * substream)317 static int fsl_asrc_dma_startup(struct snd_soc_component *component,
318 				struct snd_pcm_substream *substream)
319 {
320 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
321 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
322 	struct snd_pcm_runtime *runtime = substream->runtime;
323 	struct snd_dmaengine_dai_dma_data *dma_data;
324 	struct device *dev = component->dev;
325 	struct fsl_asrc *asrc = dev_get_drvdata(dev);
326 	struct fsl_asrc_pair *pair;
327 	struct dma_chan *tmp_chan = NULL;
328 	u8 dir = tx ? OUT : IN;
329 	bool release_pair = true;
330 	int ret = 0;
331 
332 	ret = snd_pcm_hw_constraint_integer(substream->runtime,
333 					    SNDRV_PCM_HW_PARAM_PERIODS);
334 	if (ret < 0) {
335 		dev_err(dev, "failed to set pcm hw params periods\n");
336 		return ret;
337 	}
338 
339 	pair = kzalloc(sizeof(*pair) + asrc->pair_priv_size, GFP_KERNEL);
340 	if (!pair)
341 		return -ENOMEM;
342 
343 	pair->asrc = asrc;
344 	pair->private = (void *)pair + sizeof(struct fsl_asrc_pair);
345 
346 	runtime->private_data = pair;
347 
348 	/* Request a dummy pair, which will be released later.
349 	 * Request pair function needs channel num as input, for this
350 	 * dummy pair, we just request "1" channel temporarily.
351 	 */
352 	ret = asrc->request_pair(1, pair);
353 	if (ret < 0) {
354 		dev_err(dev, "failed to request asrc pair\n");
355 		goto req_pair_err;
356 	}
357 
358 	/* Request a dummy dma channel, which will be released later. */
359 	tmp_chan = asrc->get_dma_channel(pair, dir);
360 	if (!tmp_chan) {
361 		dev_err(dev, "failed to get dma channel\n");
362 		ret = -EINVAL;
363 		goto dma_chan_err;
364 	}
365 
366 	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
367 
368 	/* Refine the snd_imx_hardware according to caps of DMA. */
369 	ret = snd_dmaengine_pcm_refine_runtime_hwparams(substream,
370 							dma_data,
371 							&snd_imx_hardware,
372 							tmp_chan);
373 	if (ret < 0) {
374 		dev_err(dev, "failed to refine runtime hwparams\n");
375 		goto out;
376 	}
377 
378 	release_pair = false;
379 	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
380 
381 out:
382 	dma_release_channel(tmp_chan);
383 
384 dma_chan_err:
385 	asrc->release_pair(pair);
386 
387 req_pair_err:
388 	if (release_pair)
389 		kfree(pair);
390 
391 	return ret;
392 }
393 
fsl_asrc_dma_shutdown(struct snd_soc_component * component,struct snd_pcm_substream * substream)394 static int fsl_asrc_dma_shutdown(struct snd_soc_component *component,
395 				 struct snd_pcm_substream *substream)
396 {
397 	struct snd_pcm_runtime *runtime = substream->runtime;
398 	struct fsl_asrc_pair *pair = runtime->private_data;
399 	struct fsl_asrc *asrc;
400 
401 	if (!pair)
402 		return 0;
403 
404 	asrc = pair->asrc;
405 
406 	if (asrc->pair[pair->index] == pair)
407 		asrc->pair[pair->index] = NULL;
408 
409 	kfree(pair);
410 
411 	return 0;
412 }
413 
414 static snd_pcm_uframes_t
fsl_asrc_dma_pcm_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)415 fsl_asrc_dma_pcm_pointer(struct snd_soc_component *component,
416 			 struct snd_pcm_substream *substream)
417 {
418 	struct snd_pcm_runtime *runtime = substream->runtime;
419 	struct fsl_asrc_pair *pair = runtime->private_data;
420 
421 	return bytes_to_frames(substream->runtime, pair->pos);
422 }
423 
fsl_asrc_dma_pcm_new(struct snd_soc_component * component,struct snd_soc_pcm_runtime * rtd)424 static int fsl_asrc_dma_pcm_new(struct snd_soc_component *component,
425 				struct snd_soc_pcm_runtime *rtd)
426 {
427 	struct snd_card *card = rtd->card->snd_card;
428 	struct snd_pcm_substream *substream;
429 	struct snd_pcm *pcm = rtd->pcm;
430 	int ret, i;
431 
432 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
433 	if (ret) {
434 		dev_err(card->dev, "failed to set DMA mask\n");
435 		return ret;
436 	}
437 
438 	for_each_pcm_streams(i) {
439 		substream = pcm->streams[i].substream;
440 		if (!substream)
441 			continue;
442 
443 		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
444 				FSL_ASRC_DMABUF_SIZE, &substream->dma_buffer);
445 		if (ret) {
446 			dev_err(card->dev, "failed to allocate DMA buffer\n");
447 			goto err;
448 		}
449 	}
450 
451 	return 0;
452 
453 err:
454 	if (--i == 0 && pcm->streams[i].substream)
455 		snd_dma_free_pages(&pcm->streams[i].substream->dma_buffer);
456 
457 	return ret;
458 }
459 
fsl_asrc_dma_pcm_free(struct snd_soc_component * component,struct snd_pcm * pcm)460 static void fsl_asrc_dma_pcm_free(struct snd_soc_component *component,
461 				  struct snd_pcm *pcm)
462 {
463 	struct snd_pcm_substream *substream;
464 	int i;
465 
466 	for_each_pcm_streams(i) {
467 		substream = pcm->streams[i].substream;
468 		if (!substream)
469 			continue;
470 
471 		snd_dma_free_pages(&substream->dma_buffer);
472 		substream->dma_buffer.area = NULL;
473 		substream->dma_buffer.addr = 0;
474 	}
475 }
476 
477 struct snd_soc_component_driver fsl_asrc_component = {
478 	.name		= DRV_NAME,
479 	.hw_params	= fsl_asrc_dma_hw_params,
480 	.hw_free	= fsl_asrc_dma_hw_free,
481 	.trigger	= fsl_asrc_dma_trigger,
482 	.open		= fsl_asrc_dma_startup,
483 	.close		= fsl_asrc_dma_shutdown,
484 	.pointer	= fsl_asrc_dma_pcm_pointer,
485 	.pcm_construct	= fsl_asrc_dma_pcm_new,
486 	.pcm_destruct	= fsl_asrc_dma_pcm_free,
487 };
488 EXPORT_SYMBOL_GPL(fsl_asrc_component);
489