xref: /openbmc/linux/sound/soc/fsl/fsl_asrc_dma.c (revision e021ae7f)
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/dma/imx-dma.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_async(pair->dma_chan[OUT]);
118 		dmaengine_terminate_async(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 	enum sdma_peripheral_type be_peripheral_type = IMX_DMATYPE_SSI;
133 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
134 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
135 	struct snd_dmaengine_dai_dma_data *dma_params_fe = NULL;
136 	struct snd_dmaengine_dai_dma_data *dma_params_be = NULL;
137 	struct snd_pcm_runtime *runtime = substream->runtime;
138 	struct fsl_asrc_pair *pair = runtime->private_data;
139 	struct dma_chan *tmp_chan = NULL, *be_chan = NULL;
140 	struct snd_soc_component *component_be = NULL;
141 	struct fsl_asrc *asrc = pair->asrc;
142 	struct dma_slave_config config_fe = {}, config_be = {};
143 	struct sdma_peripheral_config audio_config;
144 	enum asrc_pair_index index = pair->index;
145 	struct device *dev = component->dev;
146 	struct device_node *of_dma_node;
147 	int stream = substream->stream;
148 	struct imx_dma_data *tmp_data;
149 	struct snd_soc_dpcm *dpcm;
150 	struct device *dev_be;
151 	u8 dir = tx ? OUT : IN;
152 	dma_cap_mask_t mask;
153 	int ret, width;
154 
155 	/* Fetch the Back-End dma_data from DPCM */
156 	for_each_dpcm_be(rtd, stream, dpcm) {
157 		struct snd_soc_pcm_runtime *be = dpcm->be;
158 		struct snd_pcm_substream *substream_be;
159 		struct snd_soc_dai *dai = asoc_rtd_to_cpu(be, 0);
160 
161 		if (dpcm->fe != rtd)
162 			continue;
163 
164 		substream_be = snd_soc_dpcm_get_substream(be, stream);
165 		dma_params_be = snd_soc_dai_get_dma_data(dai, substream_be);
166 		dev_be = dai->dev;
167 		break;
168 	}
169 
170 	if (!dma_params_be) {
171 		dev_err(dev, "failed to get the substream of Back-End\n");
172 		return -EINVAL;
173 	}
174 
175 	/* Override dma_data of the Front-End and config its dmaengine */
176 	dma_params_fe = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
177 	dma_params_fe->addr = asrc->paddr + asrc->get_fifo_addr(!dir, index);
178 	dma_params_fe->maxburst = dma_params_be->maxburst;
179 
180 	pair->dma_chan[!dir] = asrc->get_dma_channel(pair, !dir);
181 	if (!pair->dma_chan[!dir]) {
182 		dev_err(dev, "failed to request DMA channel\n");
183 		return -EINVAL;
184 	}
185 
186 	ret = snd_dmaengine_pcm_prepare_slave_config(substream, params, &config_fe);
187 	if (ret) {
188 		dev_err(dev, "failed to prepare DMA config for Front-End\n");
189 		return ret;
190 	}
191 
192 	ret = dmaengine_slave_config(pair->dma_chan[!dir], &config_fe);
193 	if (ret) {
194 		dev_err(dev, "failed to config DMA channel for Front-End\n");
195 		return ret;
196 	}
197 
198 	/* Request and config DMA channel for Back-End */
199 	dma_cap_zero(mask);
200 	dma_cap_set(DMA_SLAVE, mask);
201 	dma_cap_set(DMA_CYCLIC, mask);
202 
203 	/*
204 	 * The Back-End device might have already requested a DMA channel,
205 	 * so try to reuse it first, and then request a new one upon NULL.
206 	 */
207 	component_be = snd_soc_lookup_component_nolocked(dev_be, SND_DMAENGINE_PCM_DRV_NAME);
208 	if (component_be) {
209 		be_chan = soc_component_to_pcm(component_be)->chan[substream->stream];
210 		tmp_chan = be_chan;
211 	}
212 	if (!tmp_chan) {
213 		tmp_chan = dma_request_chan(dev_be, tx ? "tx" : "rx");
214 		if (IS_ERR(tmp_chan)) {
215 			dev_err(dev, "failed to request DMA channel for Back-End\n");
216 			return -EINVAL;
217 		}
218 	}
219 
220 	/*
221 	 * An EDMA DEV_TO_DEV channel is fixed and bound with DMA event of each
222 	 * peripheral, unlike SDMA channel that is allocated dynamically. So no
223 	 * need to configure dma_request and dma_request2, but get dma_chan of
224 	 * Back-End device directly via dma_request_chan.
225 	 */
226 	if (!asrc->use_edma) {
227 		/* Get DMA request of Back-End */
228 		tmp_data = tmp_chan->private;
229 		pair->dma_data.dma_request = tmp_data->dma_request;
230 		be_peripheral_type = tmp_data->peripheral_type;
231 		if (!be_chan)
232 			dma_release_channel(tmp_chan);
233 
234 		/* Get DMA request of Front-End */
235 		tmp_chan = asrc->get_dma_channel(pair, dir);
236 		tmp_data = tmp_chan->private;
237 		pair->dma_data.dma_request2 = tmp_data->dma_request;
238 		pair->dma_data.peripheral_type = tmp_data->peripheral_type;
239 		pair->dma_data.priority = tmp_data->priority;
240 		dma_release_channel(tmp_chan);
241 
242 		of_dma_node = pair->dma_chan[!dir]->device->dev->of_node;
243 		pair->dma_chan[dir] =
244 			__dma_request_channel(&mask, filter, &pair->dma_data,
245 					      of_dma_node);
246 		pair->req_dma_chan = true;
247 	} else {
248 		pair->dma_chan[dir] = tmp_chan;
249 		/* Do not flag to release if we are reusing the Back-End one */
250 		pair->req_dma_chan = !be_chan;
251 	}
252 
253 	if (!pair->dma_chan[dir]) {
254 		dev_err(dev, "failed to request DMA channel for Back-End\n");
255 		return -EINVAL;
256 	}
257 
258 	width = snd_pcm_format_physical_width(asrc->asrc_format);
259 	if (width < 8 || width > 64)
260 		return -EINVAL;
261 	else if (width == 8)
262 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
263 	else if (width == 16)
264 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
265 	else if (width == 24)
266 		buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
267 	else if (width <= 32)
268 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
269 	else
270 		buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
271 
272 	config_be.direction = DMA_DEV_TO_DEV;
273 	config_be.src_addr_width = buswidth;
274 	config_be.src_maxburst = dma_params_be->maxburst;
275 	config_be.dst_addr_width = buswidth;
276 	config_be.dst_maxburst = dma_params_be->maxburst;
277 
278 	memset(&audio_config, 0, sizeof(audio_config));
279 	config_be.peripheral_config = &audio_config;
280 	config_be.peripheral_size  = sizeof(audio_config);
281 
282 	if (tx && (be_peripheral_type == IMX_DMATYPE_SSI_DUAL ||
283 		   be_peripheral_type == IMX_DMATYPE_SPDIF))
284 		audio_config.n_fifos_dst = 2;
285 	if (!tx && (be_peripheral_type == IMX_DMATYPE_SSI_DUAL ||
286 		    be_peripheral_type == IMX_DMATYPE_SPDIF))
287 		audio_config.n_fifos_src = 2;
288 
289 	if (tx) {
290 		config_be.src_addr = asrc->paddr + asrc->get_fifo_addr(OUT, index);
291 		config_be.dst_addr = dma_params_be->addr;
292 	} else {
293 		config_be.dst_addr = asrc->paddr + asrc->get_fifo_addr(IN, index);
294 		config_be.src_addr = dma_params_be->addr;
295 	}
296 
297 	ret = dmaengine_slave_config(pair->dma_chan[dir], &config_be);
298 	if (ret) {
299 		dev_err(dev, "failed to config DMA channel for Back-End\n");
300 		if (pair->req_dma_chan)
301 			dma_release_channel(pair->dma_chan[dir]);
302 		return ret;
303 	}
304 
305 	return 0;
306 }
307 
308 static int fsl_asrc_dma_hw_free(struct snd_soc_component *component,
309 				struct snd_pcm_substream *substream)
310 {
311 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
312 	struct snd_pcm_runtime *runtime = substream->runtime;
313 	struct fsl_asrc_pair *pair = runtime->private_data;
314 	u8 dir = tx ? OUT : IN;
315 
316 	if (pair->dma_chan[!dir])
317 		dma_release_channel(pair->dma_chan[!dir]);
318 
319 	/* release dev_to_dev chan if we aren't reusing the Back-End one */
320 	if (pair->dma_chan[dir] && pair->req_dma_chan)
321 		dma_release_channel(pair->dma_chan[dir]);
322 
323 	pair->dma_chan[!dir] = NULL;
324 	pair->dma_chan[dir] = NULL;
325 
326 	return 0;
327 }
328 
329 static int fsl_asrc_dma_startup(struct snd_soc_component *component,
330 				struct snd_pcm_substream *substream)
331 {
332 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
333 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
334 	struct snd_pcm_runtime *runtime = substream->runtime;
335 	struct snd_dmaengine_dai_dma_data *dma_data;
336 	struct device *dev = component->dev;
337 	struct fsl_asrc *asrc = dev_get_drvdata(dev);
338 	struct fsl_asrc_pair *pair;
339 	struct dma_chan *tmp_chan = NULL;
340 	u8 dir = tx ? OUT : IN;
341 	bool release_pair = true;
342 	int ret = 0;
343 
344 	ret = snd_pcm_hw_constraint_integer(substream->runtime,
345 					    SNDRV_PCM_HW_PARAM_PERIODS);
346 	if (ret < 0) {
347 		dev_err(dev, "failed to set pcm hw params periods\n");
348 		return ret;
349 	}
350 
351 	pair = kzalloc(sizeof(*pair) + asrc->pair_priv_size, GFP_KERNEL);
352 	if (!pair)
353 		return -ENOMEM;
354 
355 	pair->asrc = asrc;
356 	pair->private = (void *)pair + sizeof(struct fsl_asrc_pair);
357 
358 	runtime->private_data = pair;
359 
360 	/* Request a dummy pair, which will be released later.
361 	 * Request pair function needs channel num as input, for this
362 	 * dummy pair, we just request "1" channel temporarily.
363 	 */
364 	ret = asrc->request_pair(1, pair);
365 	if (ret < 0) {
366 		dev_err(dev, "failed to request asrc pair\n");
367 		goto req_pair_err;
368 	}
369 
370 	/* Request a dummy dma channel, which will be released later. */
371 	tmp_chan = asrc->get_dma_channel(pair, dir);
372 	if (!tmp_chan) {
373 		dev_err(dev, "failed to get dma channel\n");
374 		ret = -EINVAL;
375 		goto dma_chan_err;
376 	}
377 
378 	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
379 
380 	/* Refine the snd_imx_hardware according to caps of DMA. */
381 	ret = snd_dmaengine_pcm_refine_runtime_hwparams(substream,
382 							dma_data,
383 							&snd_imx_hardware,
384 							tmp_chan);
385 	if (ret < 0) {
386 		dev_err(dev, "failed to refine runtime hwparams\n");
387 		goto out;
388 	}
389 
390 	release_pair = false;
391 	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
392 
393 out:
394 	dma_release_channel(tmp_chan);
395 
396 dma_chan_err:
397 	asrc->release_pair(pair);
398 
399 req_pair_err:
400 	if (release_pair)
401 		kfree(pair);
402 
403 	return ret;
404 }
405 
406 static int fsl_asrc_dma_shutdown(struct snd_soc_component *component,
407 				 struct snd_pcm_substream *substream)
408 {
409 	struct snd_pcm_runtime *runtime = substream->runtime;
410 	struct fsl_asrc_pair *pair = runtime->private_data;
411 	struct fsl_asrc *asrc;
412 
413 	if (!pair)
414 		return 0;
415 
416 	asrc = pair->asrc;
417 
418 	if (asrc->pair[pair->index] == pair)
419 		asrc->pair[pair->index] = NULL;
420 
421 	kfree(pair);
422 
423 	return 0;
424 }
425 
426 static snd_pcm_uframes_t
427 fsl_asrc_dma_pcm_pointer(struct snd_soc_component *component,
428 			 struct snd_pcm_substream *substream)
429 {
430 	struct snd_pcm_runtime *runtime = substream->runtime;
431 	struct fsl_asrc_pair *pair = runtime->private_data;
432 
433 	return bytes_to_frames(substream->runtime, pair->pos);
434 }
435 
436 static int fsl_asrc_dma_pcm_new(struct snd_soc_component *component,
437 				struct snd_soc_pcm_runtime *rtd)
438 {
439 	struct snd_card *card = rtd->card->snd_card;
440 	struct snd_pcm *pcm = rtd->pcm;
441 	int ret;
442 
443 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
444 	if (ret) {
445 		dev_err(card->dev, "failed to set DMA mask\n");
446 		return ret;
447 	}
448 
449 	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
450 					    card->dev, FSL_ASRC_DMABUF_SIZE);
451 }
452 
453 struct snd_soc_component_driver fsl_asrc_component = {
454 	.name		= DRV_NAME,
455 	.hw_params	= fsl_asrc_dma_hw_params,
456 	.hw_free	= fsl_asrc_dma_hw_free,
457 	.trigger	= fsl_asrc_dma_trigger,
458 	.open		= fsl_asrc_dma_startup,
459 	.close		= fsl_asrc_dma_shutdown,
460 	.pointer	= fsl_asrc_dma_pcm_pointer,
461 	.pcm_construct	= fsl_asrc_dma_pcm_new,
462 	.legacy_dai_naming = 1,
463 };
464 EXPORT_SYMBOL_GPL(fsl_asrc_component);
465