fsl_asrc_dma.c

  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
 19static 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
 32static 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
 42static 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
 55static 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
 97static 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
127static 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 = snd_soc_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_cpu = snd_soc_rtd_to_cpu(be, 0);
160		struct snd_soc_dai *dai_codec = snd_soc_rtd_to_codec(be, 0);
161		struct snd_soc_dai *dai;
162
163		if (dpcm->fe != rtd)
164			continue;
165
166		/*
167		 * With audio graph card, original cpu dai is changed to codec
168		 * device in backend, so if cpu dai is dummy device in backend,
169		 * get the codec dai device, which is the real hardware device
170		 * connected.
171		 */
172		if (!snd_soc_dai_is_dummy(dai_cpu))
173			dai = dai_cpu;
174		else
175			dai = dai_codec;
176
177		substream_be = snd_soc_dpcm_get_substream(be, stream);
178		dma_params_be = snd_soc_dai_get_dma_data(dai, substream_be);
179		dev_be = dai->dev;
180		break;
181	}
182
183	if (!dma_params_be) {
184		dev_err(dev, "failed to get the substream of Back-End\n");
185		return -EINVAL;
186	}
187
188	/* Override dma_data of the Front-End and config its dmaengine */
189	dma_params_fe = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
190	dma_params_fe->addr = asrc->paddr + asrc->get_fifo_addr(!dir, index);
191	dma_params_fe->maxburst = dma_params_be->maxburst;
192
193	pair->dma_chan[!dir] = asrc->get_dma_channel(pair, !dir);
194	if (!pair->dma_chan[!dir]) {
195		dev_err(dev, "failed to request DMA channel\n");
196		return -EINVAL;
197	}
198
199	ret = snd_dmaengine_pcm_prepare_slave_config(substream, params, &config_fe);
200	if (ret) {
201		dev_err(dev, "failed to prepare DMA config for Front-End\n");
202		return ret;
203	}
204
205	ret = dmaengine_slave_config(pair->dma_chan[!dir], &config_fe);
206	if (ret) {
207		dev_err(dev, "failed to config DMA channel for Front-End\n");
208		return ret;
209	}
210
211	/* Request and config DMA channel for Back-End */
212	dma_cap_zero(mask);
213	dma_cap_set(DMA_SLAVE, mask);
214	dma_cap_set(DMA_CYCLIC, mask);
215
216	/*
217	 * The Back-End device might have already requested a DMA channel,
218	 * so try to reuse it first, and then request a new one upon NULL.
219	 */
220	component_be = snd_soc_lookup_component_nolocked(dev_be, SND_DMAENGINE_PCM_DRV_NAME);
221	if (component_be) {
222		be_chan = soc_component_to_pcm(component_be)->chan[substream->stream];
223		tmp_chan = be_chan;
224	}
225	if (!tmp_chan) {
226		tmp_chan = dma_request_chan(dev_be, tx ? "tx" : "rx");
227		if (IS_ERR(tmp_chan)) {
228			dev_err(dev, "failed to request DMA channel for Back-End\n");
229			return -EINVAL;
230		}
231	}
232
233	/*
234	 * An EDMA DEV_TO_DEV channel is fixed and bound with DMA event of each
235	 * peripheral, unlike SDMA channel that is allocated dynamically. So no
236	 * need to configure dma_request and dma_request2, but get dma_chan of
237	 * Back-End device directly via dma_request_chan.
238	 */
239	if (!asrc->use_edma) {
240		/* Get DMA request of Back-End */
241		tmp_data = tmp_chan->private;
242		pair->dma_data.dma_request = tmp_data->dma_request;
243		be_peripheral_type = tmp_data->peripheral_type;
244		if (!be_chan)
245			dma_release_channel(tmp_chan);
246
247		/* Get DMA request of Front-End */
248		tmp_chan = asrc->get_dma_channel(pair, dir);
249		tmp_data = tmp_chan->private;
250		pair->dma_data.dma_request2 = tmp_data->dma_request;
251		pair->dma_data.peripheral_type = tmp_data->peripheral_type;
252		pair->dma_data.priority = tmp_data->priority;
253		dma_release_channel(tmp_chan);
254
255		of_dma_node = pair->dma_chan[!dir]->device->dev->of_node;
256		pair->dma_chan[dir] =
257			__dma_request_channel(&mask, filter, &pair->dma_data,
258					      of_dma_node);
259		pair->req_dma_chan = true;
260	} else {
261		pair->dma_chan[dir] = tmp_chan;
262		/* Do not flag to release if we are reusing the Back-End one */
263		pair->req_dma_chan = !be_chan;
264	}
265
266	if (!pair->dma_chan[dir]) {
267		dev_err(dev, "failed to request DMA channel for Back-End\n");
268		return -EINVAL;
269	}
270
271	width = snd_pcm_format_physical_width(asrc->asrc_format);
272	if (width < 8 || width > 64)
273		return -EINVAL;
274	else if (width == 8)
275		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
276	else if (width == 16)
277		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
278	else if (width == 24)
279		buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
280	else if (width <= 32)
281		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
282	else
283		buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
284
285	config_be.direction = DMA_DEV_TO_DEV;
286	config_be.src_addr_width = buswidth;
287	config_be.src_maxburst = dma_params_be->maxburst;
288	config_be.dst_addr_width = buswidth;
289	config_be.dst_maxburst = dma_params_be->maxburst;
290
291	memset(&audio_config, 0, sizeof(audio_config));
292	config_be.peripheral_config = &audio_config;
293	config_be.peripheral_size  = sizeof(audio_config);
294
295	if (tx && (be_peripheral_type == IMX_DMATYPE_SSI_DUAL ||
296		   be_peripheral_type == IMX_DMATYPE_SPDIF))
297		audio_config.n_fifos_dst = 2;
298	if (!tx && (be_peripheral_type == IMX_DMATYPE_SSI_DUAL ||
299		    be_peripheral_type == IMX_DMATYPE_SPDIF))
300		audio_config.n_fifos_src = 2;
301
302	if (tx) {
303		config_be.src_addr = asrc->paddr + asrc->get_fifo_addr(OUT, index);
304		config_be.dst_addr = dma_params_be->addr;
305	} else {
306		config_be.dst_addr = asrc->paddr + asrc->get_fifo_addr(IN, index);
307		config_be.src_addr = dma_params_be->addr;
308	}
309
310	ret = dmaengine_slave_config(pair->dma_chan[dir], &config_be);
311	if (ret) {
312		dev_err(dev, "failed to config DMA channel for Back-End\n");
313		if (pair->req_dma_chan)
314			dma_release_channel(pair->dma_chan[dir]);
315		return ret;
316	}
317
318	return 0;
319}
320
321static int fsl_asrc_dma_hw_free(struct snd_soc_component *component,
322				struct snd_pcm_substream *substream)
323{
324	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
325	struct snd_pcm_runtime *runtime = substream->runtime;
326	struct fsl_asrc_pair *pair = runtime->private_data;
327	u8 dir = tx ? OUT : IN;
328
329	if (pair->dma_chan[!dir])
330		dma_release_channel(pair->dma_chan[!dir]);
331
332	/* release dev_to_dev chan if we aren't reusing the Back-End one */
333	if (pair->dma_chan[dir] && pair->req_dma_chan)
334		dma_release_channel(pair->dma_chan[dir]);
335
336	pair->dma_chan[!dir] = NULL;
337	pair->dma_chan[dir] = NULL;
338
339	return 0;
340}
341
342static int fsl_asrc_dma_startup(struct snd_soc_component *component,
343				struct snd_pcm_substream *substream)
344{
345	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
346	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
347	struct snd_pcm_runtime *runtime = substream->runtime;
348	struct snd_dmaengine_dai_dma_data *dma_data;
349	struct device *dev = component->dev;
350	struct fsl_asrc *asrc = dev_get_drvdata(dev);
351	struct fsl_asrc_pair *pair;
352	struct dma_chan *tmp_chan = NULL;
353	u8 dir = tx ? OUT : IN;
354	bool release_pair = true;
355	int ret = 0;
356
357	ret = snd_pcm_hw_constraint_integer(substream->runtime,
358					    SNDRV_PCM_HW_PARAM_PERIODS);
359	if (ret < 0) {
360		dev_err(dev, "failed to set pcm hw params periods\n");
361		return ret;
362	}
363
364	pair = kzalloc(sizeof(*pair) + asrc->pair_priv_size, GFP_KERNEL);
365	if (!pair)
366		return -ENOMEM;
367
368	pair->asrc = asrc;
369	pair->private = (void *)pair + sizeof(struct fsl_asrc_pair);
370
371	runtime->private_data = pair;
372
373	/* Request a dummy pair, which will be released later.
374	 * Request pair function needs channel num as input, for this
375	 * dummy pair, we just request "1" channel temporarily.
376	 */
377	ret = asrc->request_pair(1, pair);
378	if (ret < 0) {
379		dev_err(dev, "failed to request asrc pair\n");
380		goto req_pair_err;
381	}
382
383	/* Request a dummy dma channel, which will be released later. */
384	tmp_chan = asrc->get_dma_channel(pair, dir);
385	if (!tmp_chan) {
386		dev_err(dev, "failed to get dma channel\n");
387		ret = -EINVAL;
388		goto dma_chan_err;
389	}
390
391	dma_data = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
392
393	/* Refine the snd_imx_hardware according to caps of DMA. */
394	ret = snd_dmaengine_pcm_refine_runtime_hwparams(substream,
395							dma_data,
396							&snd_imx_hardware,
397							tmp_chan);
398	if (ret < 0) {
399		dev_err(dev, "failed to refine runtime hwparams\n");
400		goto out;
401	}
402
403	release_pair = false;
404	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
405
406out:
407	dma_release_channel(tmp_chan);
408
409dma_chan_err:
410	asrc->release_pair(pair);
411
412req_pair_err:
413	if (release_pair)
414		kfree(pair);
415
416	return ret;
417}
418
419static int fsl_asrc_dma_shutdown(struct snd_soc_component *component,
420				 struct snd_pcm_substream *substream)
421{
422	struct snd_pcm_runtime *runtime = substream->runtime;
423	struct fsl_asrc_pair *pair = runtime->private_data;
424	struct fsl_asrc *asrc;
425
426	if (!pair)
427		return 0;
428
429	asrc = pair->asrc;
430
431	if (asrc->pair[pair->index] == pair)
432		asrc->pair[pair->index] = NULL;
433
434	kfree(pair);
435
436	return 0;
437}
438
439static snd_pcm_uframes_t
440fsl_asrc_dma_pcm_pointer(struct snd_soc_component *component,
441			 struct snd_pcm_substream *substream)
442{
443	struct snd_pcm_runtime *runtime = substream->runtime;
444	struct fsl_asrc_pair *pair = runtime->private_data;
445
446	return bytes_to_frames(substream->runtime, pair->pos);
447}
448
449static int fsl_asrc_dma_pcm_new(struct snd_soc_component *component,
450				struct snd_soc_pcm_runtime *rtd)
451{
452	struct snd_card *card = rtd->card->snd_card;
453	struct snd_pcm *pcm = rtd->pcm;
454	int ret;
455
456	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
457	if (ret) {
458		dev_err(card->dev, "failed to set DMA mask\n");
459		return ret;
460	}
461
462	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
463					    card->dev, FSL_ASRC_DMABUF_SIZE);
464}
465
466struct snd_soc_component_driver fsl_asrc_component = {
467	.name		= DRV_NAME,
468	.hw_params	= fsl_asrc_dma_hw_params,
469	.hw_free	= fsl_asrc_dma_hw_free,
470	.trigger	= fsl_asrc_dma_trigger,
471	.open		= fsl_asrc_dma_startup,
472	.close		= fsl_asrc_dma_shutdown,
473	.pointer	= fsl_asrc_dma_pcm_pointer,
474	.pcm_construct	= fsl_asrc_dma_pcm_new,
475	.legacy_dai_naming = 1,
476#ifdef CONFIG_DEBUG_FS
477	.debugfs_prefix	= "asrc",
478#endif
479};
480EXPORT_SYMBOL_GPL(fsl_asrc_component);