xref: /openbmc/linux/sound/soc/fsl/fsl_asrc_dma.c (revision 2cf1c348)
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 
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 
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 
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 
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 
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 	struct device_node *of_dma_node;
145 	int stream = substream->stream;
146 	struct imx_dma_data *tmp_data;
147 	struct snd_soc_dpcm *dpcm;
148 	struct device *dev_be;
149 	u8 dir = tx ? OUT : IN;
150 	dma_cap_mask_t mask;
151 	int ret, width;
152 
153 	/* Fetch the Back-End dma_data from DPCM */
154 	for_each_dpcm_be(rtd, stream, dpcm) {
155 		struct snd_soc_pcm_runtime *be = dpcm->be;
156 		struct snd_pcm_substream *substream_be;
157 		struct snd_soc_dai *dai = asoc_rtd_to_cpu(be, 0);
158 
159 		if (dpcm->fe != rtd)
160 			continue;
161 
162 		substream_be = snd_soc_dpcm_get_substream(be, stream);
163 		dma_params_be = snd_soc_dai_get_dma_data(dai, substream_be);
164 		dev_be = dai->dev;
165 		break;
166 	}
167 
168 	if (!dma_params_be) {
169 		dev_err(dev, "failed to get the substream of Back-End\n");
170 		return -EINVAL;
171 	}
172 
173 	/* Override dma_data of the Front-End and config its dmaengine */
174 	dma_params_fe = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
175 	dma_params_fe->addr = asrc->paddr + asrc->get_fifo_addr(!dir, index);
176 	dma_params_fe->maxburst = dma_params_be->maxburst;
177 
178 	pair->dma_chan[!dir] = asrc->get_dma_channel(pair, !dir);
179 	if (!pair->dma_chan[!dir]) {
180 		dev_err(dev, "failed to request DMA channel\n");
181 		return -EINVAL;
182 	}
183 
184 	memset(&config_fe, 0, sizeof(config_fe));
185 	ret = snd_dmaengine_pcm_prepare_slave_config(substream, params, &config_fe);
186 	if (ret) {
187 		dev_err(dev, "failed to prepare DMA config for Front-End\n");
188 		return ret;
189 	}
190 
191 	ret = dmaengine_slave_config(pair->dma_chan[!dir], &config_fe);
192 	if (ret) {
193 		dev_err(dev, "failed to config DMA channel for Front-End\n");
194 		return ret;
195 	}
196 
197 	/* Request and config DMA channel for Back-End */
198 	dma_cap_zero(mask);
199 	dma_cap_set(DMA_SLAVE, mask);
200 	dma_cap_set(DMA_CYCLIC, mask);
201 
202 	/*
203 	 * The Back-End device might have already requested a DMA channel,
204 	 * so try to reuse it first, and then request a new one upon NULL.
205 	 */
206 	component_be = snd_soc_lookup_component_nolocked(dev_be, SND_DMAENGINE_PCM_DRV_NAME);
207 	if (component_be) {
208 		be_chan = soc_component_to_pcm(component_be)->chan[substream->stream];
209 		tmp_chan = be_chan;
210 	}
211 	if (!tmp_chan)
212 		tmp_chan = dma_request_slave_channel(dev_be, tx ? "tx" : "rx");
213 
214 	/*
215 	 * An EDMA DEV_TO_DEV channel is fixed and bound with DMA event of each
216 	 * peripheral, unlike SDMA channel that is allocated dynamically. So no
217 	 * need to configure dma_request and dma_request2, but get dma_chan of
218 	 * Back-End device directly via dma_request_slave_channel.
219 	 */
220 	if (!asrc->use_edma) {
221 		/* Get DMA request of Back-End */
222 		tmp_data = tmp_chan->private;
223 		pair->dma_data.dma_request = tmp_data->dma_request;
224 		if (!be_chan)
225 			dma_release_channel(tmp_chan);
226 
227 		/* Get DMA request of Front-End */
228 		tmp_chan = asrc->get_dma_channel(pair, dir);
229 		tmp_data = tmp_chan->private;
230 		pair->dma_data.dma_request2 = tmp_data->dma_request;
231 		pair->dma_data.peripheral_type = tmp_data->peripheral_type;
232 		pair->dma_data.priority = tmp_data->priority;
233 		dma_release_channel(tmp_chan);
234 
235 		of_dma_node = pair->dma_chan[!dir]->device->dev->of_node;
236 		pair->dma_chan[dir] =
237 			__dma_request_channel(&mask, filter, &pair->dma_data,
238 					      of_dma_node);
239 		pair->req_dma_chan = true;
240 	} else {
241 		pair->dma_chan[dir] = tmp_chan;
242 		/* Do not flag to release if we are reusing the Back-End one */
243 		pair->req_dma_chan = !be_chan;
244 	}
245 
246 	if (!pair->dma_chan[dir]) {
247 		dev_err(dev, "failed to request DMA channel for Back-End\n");
248 		return -EINVAL;
249 	}
250 
251 	width = snd_pcm_format_physical_width(asrc->asrc_format);
252 	if (width < 8 || width > 64)
253 		return -EINVAL;
254 	else if (width == 8)
255 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
256 	else if (width == 16)
257 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
258 	else if (width == 24)
259 		buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
260 	else if (width <= 32)
261 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
262 	else
263 		buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
264 
265 	config_be.direction = DMA_DEV_TO_DEV;
266 	config_be.src_addr_width = buswidth;
267 	config_be.src_maxburst = dma_params_be->maxburst;
268 	config_be.dst_addr_width = buswidth;
269 	config_be.dst_maxburst = dma_params_be->maxburst;
270 
271 	if (tx) {
272 		config_be.src_addr = asrc->paddr + asrc->get_fifo_addr(OUT, index);
273 		config_be.dst_addr = dma_params_be->addr;
274 	} else {
275 		config_be.dst_addr = asrc->paddr + asrc->get_fifo_addr(IN, index);
276 		config_be.src_addr = dma_params_be->addr;
277 	}
278 
279 	ret = dmaengine_slave_config(pair->dma_chan[dir], &config_be);
280 	if (ret) {
281 		dev_err(dev, "failed to config DMA channel for Back-End\n");
282 		if (pair->req_dma_chan)
283 			dma_release_channel(pair->dma_chan[dir]);
284 		return ret;
285 	}
286 
287 	return 0;
288 }
289 
290 static int fsl_asrc_dma_hw_free(struct snd_soc_component *component,
291 				struct snd_pcm_substream *substream)
292 {
293 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
294 	struct snd_pcm_runtime *runtime = substream->runtime;
295 	struct fsl_asrc_pair *pair = runtime->private_data;
296 	u8 dir = tx ? OUT : IN;
297 
298 	if (pair->dma_chan[!dir])
299 		dma_release_channel(pair->dma_chan[!dir]);
300 
301 	/* release dev_to_dev chan if we aren't reusing the Back-End one */
302 	if (pair->dma_chan[dir] && pair->req_dma_chan)
303 		dma_release_channel(pair->dma_chan[dir]);
304 
305 	pair->dma_chan[!dir] = NULL;
306 	pair->dma_chan[dir] = NULL;
307 
308 	return 0;
309 }
310 
311 static int fsl_asrc_dma_startup(struct snd_soc_component *component,
312 				struct snd_pcm_substream *substream)
313 {
314 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
315 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
316 	struct snd_pcm_runtime *runtime = substream->runtime;
317 	struct snd_dmaengine_dai_dma_data *dma_data;
318 	struct device *dev = component->dev;
319 	struct fsl_asrc *asrc = dev_get_drvdata(dev);
320 	struct fsl_asrc_pair *pair;
321 	struct dma_chan *tmp_chan = NULL;
322 	u8 dir = tx ? OUT : IN;
323 	bool release_pair = true;
324 	int ret = 0;
325 
326 	ret = snd_pcm_hw_constraint_integer(substream->runtime,
327 					    SNDRV_PCM_HW_PARAM_PERIODS);
328 	if (ret < 0) {
329 		dev_err(dev, "failed to set pcm hw params periods\n");
330 		return ret;
331 	}
332 
333 	pair = kzalloc(sizeof(*pair) + asrc->pair_priv_size, GFP_KERNEL);
334 	if (!pair)
335 		return -ENOMEM;
336 
337 	pair->asrc = asrc;
338 	pair->private = (void *)pair + sizeof(struct fsl_asrc_pair);
339 
340 	runtime->private_data = pair;
341 
342 	/* Request a dummy pair, which will be released later.
343 	 * Request pair function needs channel num as input, for this
344 	 * dummy pair, we just request "1" channel temporarily.
345 	 */
346 	ret = asrc->request_pair(1, pair);
347 	if (ret < 0) {
348 		dev_err(dev, "failed to request asrc pair\n");
349 		goto req_pair_err;
350 	}
351 
352 	/* Request a dummy dma channel, which will be released later. */
353 	tmp_chan = asrc->get_dma_channel(pair, dir);
354 	if (!tmp_chan) {
355 		dev_err(dev, "failed to get dma channel\n");
356 		ret = -EINVAL;
357 		goto dma_chan_err;
358 	}
359 
360 	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
361 
362 	/* Refine the snd_imx_hardware according to caps of DMA. */
363 	ret = snd_dmaengine_pcm_refine_runtime_hwparams(substream,
364 							dma_data,
365 							&snd_imx_hardware,
366 							tmp_chan);
367 	if (ret < 0) {
368 		dev_err(dev, "failed to refine runtime hwparams\n");
369 		goto out;
370 	}
371 
372 	release_pair = false;
373 	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
374 
375 out:
376 	dma_release_channel(tmp_chan);
377 
378 dma_chan_err:
379 	asrc->release_pair(pair);
380 
381 req_pair_err:
382 	if (release_pair)
383 		kfree(pair);
384 
385 	return ret;
386 }
387 
388 static int fsl_asrc_dma_shutdown(struct snd_soc_component *component,
389 				 struct snd_pcm_substream *substream)
390 {
391 	struct snd_pcm_runtime *runtime = substream->runtime;
392 	struct fsl_asrc_pair *pair = runtime->private_data;
393 	struct fsl_asrc *asrc;
394 
395 	if (!pair)
396 		return 0;
397 
398 	asrc = pair->asrc;
399 
400 	if (asrc->pair[pair->index] == pair)
401 		asrc->pair[pair->index] = NULL;
402 
403 	kfree(pair);
404 
405 	return 0;
406 }
407 
408 static snd_pcm_uframes_t
409 fsl_asrc_dma_pcm_pointer(struct snd_soc_component *component,
410 			 struct snd_pcm_substream *substream)
411 {
412 	struct snd_pcm_runtime *runtime = substream->runtime;
413 	struct fsl_asrc_pair *pair = runtime->private_data;
414 
415 	return bytes_to_frames(substream->runtime, pair->pos);
416 }
417 
418 static int fsl_asrc_dma_pcm_new(struct snd_soc_component *component,
419 				struct snd_soc_pcm_runtime *rtd)
420 {
421 	struct snd_card *card = rtd->card->snd_card;
422 	struct snd_pcm *pcm = rtd->pcm;
423 	int ret;
424 
425 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
426 	if (ret) {
427 		dev_err(card->dev, "failed to set DMA mask\n");
428 		return ret;
429 	}
430 
431 	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
432 					    card->dev, FSL_ASRC_DMABUF_SIZE);
433 }
434 
435 struct snd_soc_component_driver fsl_asrc_component = {
436 	.name		= DRV_NAME,
437 	.hw_params	= fsl_asrc_dma_hw_params,
438 	.hw_free	= fsl_asrc_dma_hw_free,
439 	.trigger	= fsl_asrc_dma_trigger,
440 	.open		= fsl_asrc_dma_startup,
441 	.close		= fsl_asrc_dma_shutdown,
442 	.pointer	= fsl_asrc_dma_pcm_pointer,
443 	.pcm_construct	= fsl_asrc_dma_pcm_new,
444 };
445 EXPORT_SYMBOL_GPL(fsl_asrc_component);
446