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  
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_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  
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  	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 = snd_soc_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(snd_soc_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  
fsl_asrc_dma_hw_free(struct snd_soc_component * component,struct snd_pcm_substream * substream)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  
fsl_asrc_dma_startup(struct snd_soc_component * component,struct snd_pcm_substream * substream)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 = snd_soc_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(snd_soc_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  
fsl_asrc_dma_shutdown(struct snd_soc_component * component,struct snd_pcm_substream * substream)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
fsl_asrc_dma_pcm_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)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  
fsl_asrc_dma_pcm_new(struct snd_soc_component * component,struct snd_soc_pcm_runtime * rtd)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