1/*
2 * Freescale ASRC ALSA SoC Platform (DMA) driver
3 *
4 * Copyright (C) 2014 Freescale Semiconductor, Inc.
5 *
6 * Author: Nicolin Chen <nicoleotsuka@gmail.com>
7 *
8 * This file is licensed under the terms of the GNU General Public License
9 * version 2. This program is licensed "as is" without any warranty of any
10 * kind, whether express or implied.
11 */
12
13#include <linux/dma-mapping.h>
14#include <linux/module.h>
15#include <linux/platform_data/dma-imx.h>
16#include <sound/dmaengine_pcm.h>
17#include <sound/pcm_params.h>
18
19#include "fsl_asrc.h"
20
21#define FSL_ASRC_DMABUF_SIZE	(256 * 1024)
22
23static struct snd_pcm_hardware snd_imx_hardware = {
24	.info = SNDRV_PCM_INFO_INTERLEAVED |
25		SNDRV_PCM_INFO_BLOCK_TRANSFER |
26		SNDRV_PCM_INFO_MMAP |
27		SNDRV_PCM_INFO_MMAP_VALID |
28		SNDRV_PCM_INFO_PAUSE |
29		SNDRV_PCM_INFO_RESUME,
30	.buffer_bytes_max = FSL_ASRC_DMABUF_SIZE,
31	.period_bytes_min = 128,
32	.period_bytes_max = 65535, /* Limited by SDMA engine */
33	.periods_min = 2,
34	.periods_max = 255,
35	.fifo_size = 0,
36};
37
38static bool filter(struct dma_chan *chan, void *param)
39{
40	if (!imx_dma_is_general_purpose(chan))
41		return false;
42
43	chan->private = param;
44
45	return true;
46}
47
48static void fsl_asrc_dma_complete(void *arg)
49{
50	struct snd_pcm_substream *substream = arg;
51	struct snd_pcm_runtime *runtime = substream->runtime;
52	struct fsl_asrc_pair *pair = runtime->private_data;
53
54	pair->pos += snd_pcm_lib_period_bytes(substream);
55	if (pair->pos >= snd_pcm_lib_buffer_bytes(substream))
56		pair->pos = 0;
57
58	snd_pcm_period_elapsed(substream);
59}
60
61static int fsl_asrc_dma_prepare_and_submit(struct snd_pcm_substream *substream)
62{
63	u8 dir = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? OUT : IN;
64	struct snd_soc_pcm_runtime *rtd = substream->private_data;
65	struct snd_pcm_runtime *runtime = substream->runtime;
66	struct fsl_asrc_pair *pair = runtime->private_data;
67	struct device *dev = rtd->platform->dev;
68	unsigned long flags = DMA_CTRL_ACK;
69
70	/* Prepare and submit Front-End DMA channel */
71	if (!substream->runtime->no_period_wakeup)
72		flags |= DMA_PREP_INTERRUPT;
73
74	pair->pos = 0;
75	pair->desc[!dir] = dmaengine_prep_dma_cyclic(
76			pair->dma_chan[!dir], runtime->dma_addr,
77			snd_pcm_lib_buffer_bytes(substream),
78			snd_pcm_lib_period_bytes(substream),
79			dir == OUT ? DMA_TO_DEVICE : DMA_FROM_DEVICE, flags);
80	if (!pair->desc[!dir]) {
81		dev_err(dev, "failed to prepare slave DMA for Front-End\n");
82		return -ENOMEM;
83	}
84
85	pair->desc[!dir]->callback = fsl_asrc_dma_complete;
86	pair->desc[!dir]->callback_param = substream;
87
88	dmaengine_submit(pair->desc[!dir]);
89
90	/* Prepare and submit Back-End DMA channel */
91	pair->desc[dir] = dmaengine_prep_dma_cyclic(
92			pair->dma_chan[dir], 0xffff, 64, 64, DMA_DEV_TO_DEV, 0);
93	if (!pair->desc[dir]) {
94		dev_err(dev, "failed to prepare slave DMA for Back-End\n");
95		return -ENOMEM;
96	}
97
98	dmaengine_submit(pair->desc[dir]);
99
100	return 0;
101}
102
103static int fsl_asrc_dma_trigger(struct snd_pcm_substream *substream, int cmd)
104{
105	struct snd_pcm_runtime *runtime = substream->runtime;
106	struct fsl_asrc_pair *pair = runtime->private_data;
107	int ret;
108
109	switch (cmd) {
110	case SNDRV_PCM_TRIGGER_START:
111	case SNDRV_PCM_TRIGGER_RESUME:
112	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
113		ret = fsl_asrc_dma_prepare_and_submit(substream);
114		if (ret)
115			return ret;
116		dma_async_issue_pending(pair->dma_chan[IN]);
117		dma_async_issue_pending(pair->dma_chan[OUT]);
118		break;
119	case SNDRV_PCM_TRIGGER_STOP:
120	case SNDRV_PCM_TRIGGER_SUSPEND:
121	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
122		dmaengine_terminate_all(pair->dma_chan[OUT]);
123		dmaengine_terminate_all(pair->dma_chan[IN]);
124		break;
125	default:
126		return -EINVAL;
127	}
128
129	return 0;
130}
131
132static int fsl_asrc_dma_hw_params(struct snd_pcm_substream *substream,
133				  struct snd_pcm_hw_params *params)
134{
135	enum dma_slave_buswidth buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
136	struct snd_soc_pcm_runtime *rtd = substream->private_data;
137	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
138	struct snd_dmaengine_dai_dma_data *dma_params_fe = NULL;
139	struct snd_dmaengine_dai_dma_data *dma_params_be = NULL;
140	struct snd_pcm_runtime *runtime = substream->runtime;
141	struct fsl_asrc_pair *pair = runtime->private_data;
142	struct fsl_asrc *asrc_priv = pair->asrc_priv;
143	struct dma_slave_config config_fe, config_be;
144	enum asrc_pair_index index = pair->index;
145	struct device *dev = rtd->platform->dev;
146	int stream = substream->stream;
147	struct imx_dma_data *tmp_data;
148	struct snd_soc_dpcm *dpcm;
149	struct dma_chan *tmp_chan;
150	struct device *dev_be;
151	u8 dir = tx ? OUT : IN;
152	dma_cap_mask_t mask;
153	int ret;
154
155	/* Fetch the Back-End dma_data from DPCM */
156	list_for_each_entry(dpcm, &rtd->dpcm[stream].be_clients, list_be) {
157		struct snd_soc_pcm_runtime *be = dpcm->be;
158		struct snd_pcm_substream *substream_be;
159		struct snd_soc_dai *dai = be->cpu_dai;
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(rtd->cpu_dai, substream);
177	dma_params_fe->addr = asrc_priv->paddr + REG_ASRDx(!dir, index);
178	dma_params_fe->maxburst = dma_params_be->maxburst;
179
180	pair->dma_chan[!dir] = fsl_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	memset(&config_fe, 0, sizeof(config_fe));
187	ret = snd_dmaengine_pcm_prepare_slave_config(substream, params, &config_fe);
188	if (ret) {
189		dev_err(dev, "failed to prepare DMA config for Front-End\n");
190		return ret;
191	}
192
193	ret = dmaengine_slave_config(pair->dma_chan[!dir], &config_fe);
194	if (ret) {
195		dev_err(dev, "failed to config DMA channel for Front-End\n");
196		return ret;
197	}
198
199	/* Request and config DMA channel for Back-End */
200	dma_cap_zero(mask);
201	dma_cap_set(DMA_SLAVE, mask);
202	dma_cap_set(DMA_CYCLIC, mask);
203
204	/* Get DMA request of Back-End */
205	tmp_chan = dma_request_slave_channel(dev_be, tx ? "tx" : "rx");
206	tmp_data = tmp_chan->private;
207	pair->dma_data.dma_request = tmp_data->dma_request;
208	dma_release_channel(tmp_chan);
209
210	/* Get DMA request of Front-End */
211	tmp_chan = fsl_asrc_get_dma_channel(pair, dir);
212	tmp_data = tmp_chan->private;
213	pair->dma_data.dma_request2 = tmp_data->dma_request;
214	pair->dma_data.peripheral_type = tmp_data->peripheral_type;
215	pair->dma_data.priority = tmp_data->priority;
216	dma_release_channel(tmp_chan);
217
218	pair->dma_chan[dir] = dma_request_channel(mask, filter, &pair->dma_data);
219	if (!pair->dma_chan[dir]) {
220		dev_err(dev, "failed to request DMA channel for Back-End\n");
221		return -EINVAL;
222	}
223
224	if (asrc_priv->asrc_width == 16)
225		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
226	else
227		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
228
229	config_be.direction = DMA_DEV_TO_DEV;
230	config_be.src_addr_width = buswidth;
231	config_be.src_maxburst = dma_params_be->maxburst;
232	config_be.dst_addr_width = buswidth;
233	config_be.dst_maxburst = dma_params_be->maxburst;
234
235	if (tx) {
236		config_be.src_addr = asrc_priv->paddr + REG_ASRDO(index);
237		config_be.dst_addr = dma_params_be->addr;
238	} else {
239		config_be.dst_addr = asrc_priv->paddr + REG_ASRDI(index);
240		config_be.src_addr = dma_params_be->addr;
241	}
242
243	ret = dmaengine_slave_config(pair->dma_chan[dir], &config_be);
244	if (ret) {
245		dev_err(dev, "failed to config DMA channel for Back-End\n");
246		return ret;
247	}
248
249	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
250
251	return 0;
252}
253
254static int fsl_asrc_dma_hw_free(struct snd_pcm_substream *substream)
255{
256	struct snd_pcm_runtime *runtime = substream->runtime;
257	struct fsl_asrc_pair *pair = runtime->private_data;
258
259	snd_pcm_set_runtime_buffer(substream, NULL);
260
261	if (pair->dma_chan[IN])
262		dma_release_channel(pair->dma_chan[IN]);
263
264	if (pair->dma_chan[OUT])
265		dma_release_channel(pair->dma_chan[OUT]);
266
267	pair->dma_chan[IN] = NULL;
268	pair->dma_chan[OUT] = NULL;
269
270	return 0;
271}
272
273static int fsl_asrc_dma_startup(struct snd_pcm_substream *substream)
274{
275	struct snd_soc_pcm_runtime *rtd = substream->private_data;
276	struct snd_pcm_runtime *runtime = substream->runtime;
277	struct device *dev = rtd->platform->dev;
278	struct fsl_asrc *asrc_priv = dev_get_drvdata(dev);
279	struct fsl_asrc_pair *pair;
280
281	pair = kzalloc(sizeof(struct fsl_asrc_pair), GFP_KERNEL);
282	if (!pair) {
283		dev_err(dev, "failed to allocate pair\n");
284		return -ENOMEM;
285	}
286
287	pair->asrc_priv = asrc_priv;
288
289	runtime->private_data = pair;
290
291	snd_pcm_hw_constraint_integer(substream->runtime,
292				      SNDRV_PCM_HW_PARAM_PERIODS);
293	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
294
295	return 0;
296}
297
298static int fsl_asrc_dma_shutdown(struct snd_pcm_substream *substream)
299{
300	struct snd_pcm_runtime *runtime = substream->runtime;
301	struct fsl_asrc_pair *pair = runtime->private_data;
302	struct fsl_asrc *asrc_priv;
303
304	if (!pair)
305		return 0;
306
307	asrc_priv = pair->asrc_priv;
308
309	if (asrc_priv->pair[pair->index] == pair)
310		asrc_priv->pair[pair->index] = NULL;
311
312	kfree(pair);
313
314	return 0;
315}
316
317static snd_pcm_uframes_t fsl_asrc_dma_pcm_pointer(struct snd_pcm_substream *substream)
318{
319	struct snd_pcm_runtime *runtime = substream->runtime;
320	struct fsl_asrc_pair *pair = runtime->private_data;
321
322	return bytes_to_frames(substream->runtime, pair->pos);
323}
324
325static struct snd_pcm_ops fsl_asrc_dma_pcm_ops = {
326	.ioctl		= snd_pcm_lib_ioctl,
327	.hw_params	= fsl_asrc_dma_hw_params,
328	.hw_free	= fsl_asrc_dma_hw_free,
329	.trigger	= fsl_asrc_dma_trigger,
330	.open		= fsl_asrc_dma_startup,
331	.close		= fsl_asrc_dma_shutdown,
332	.pointer	= fsl_asrc_dma_pcm_pointer,
333};
334
335static int fsl_asrc_dma_pcm_new(struct snd_soc_pcm_runtime *rtd)
336{
337	struct snd_card *card = rtd->card->snd_card;
338	struct snd_pcm_substream *substream;
339	struct snd_pcm *pcm = rtd->pcm;
340	int ret, i;
341
342	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
343	if (ret) {
344		dev_err(card->dev, "failed to set DMA mask\n");
345		return ret;
346	}
347
348	for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_LAST; i++) {
349		substream = pcm->streams[i].substream;
350		if (!substream)
351			continue;
352
353		ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
354				FSL_ASRC_DMABUF_SIZE, &substream->dma_buffer);
355		if (ret) {
356			dev_err(card->dev, "failed to allocate DMA buffer\n");
357			goto err;
358		}
359	}
360
361	return 0;
362
363err:
364	if (--i == 0 && pcm->streams[i].substream)
365		snd_dma_free_pages(&pcm->streams[i].substream->dma_buffer);
366
367	return ret;
368}
369
370static void fsl_asrc_dma_pcm_free(struct snd_pcm *pcm)
371{
372	struct snd_pcm_substream *substream;
373	int i;
374
375	for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_LAST; i++) {
376		substream = pcm->streams[i].substream;
377		if (!substream)
378			continue;
379
380		snd_dma_free_pages(&substream->dma_buffer);
381		substream->dma_buffer.area = NULL;
382		substream->dma_buffer.addr = 0;
383	}
384}
385
386struct snd_soc_platform_driver fsl_asrc_platform = {
387	.ops		= &fsl_asrc_dma_pcm_ops,
388	.pcm_new	= fsl_asrc_dma_pcm_new,
389	.pcm_free	= fsl_asrc_dma_pcm_free,
390};
391EXPORT_SYMBOL_GPL(fsl_asrc_platform);
392