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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Copyright (C) 2012, Analog Devices Inc.
  4 *	Author: Lars-Peter Clausen <lars@metafoo.de>
  5 *
  6 *  Based on:
  7 *	imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
  8 *	mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc.
  9 *	ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
 10 *		      Copyright (C) 2006 Applied Data Systems
 11 */
 12#include <linux/module.h>
 13#include <linux/init.h>
 14#include <linux/dmaengine.h>
 15#include <linux/slab.h>
 16#include <sound/pcm.h>
 17#include <sound/pcm_params.h>
 18#include <sound/soc.h>
 19
 20#include <sound/dmaengine_pcm.h>
 21
 22struct dmaengine_pcm_runtime_data {
 23	struct dma_chan *dma_chan;
 24	dma_cookie_t cookie;
 25
 26	unsigned int pos;
 27};
 28
 29static inline struct dmaengine_pcm_runtime_data *substream_to_prtd(
 30	const struct snd_pcm_substream *substream)
 31{
 32	return substream->runtime->private_data;
 33}
 34
 35struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream)
 36{
 37	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 38
 39	return prtd->dma_chan;
 40}
 41EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan);
 42
 43/**
 44 * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config
 45 * @substream: PCM substream
 46 * @params: hw_params
 47 * @slave_config: DMA slave config
 48 *
 49 * This function can be used to initialize a dma_slave_config from a substream
 50 * and hw_params in a dmaengine based PCM driver implementation.
 51 */
 52int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
 53	const struct snd_pcm_hw_params *params,
 54	struct dma_slave_config *slave_config)
 55{
 56	enum dma_slave_buswidth buswidth;
 57	int bits;
 58
 59	bits = params_physical_width(params);
 60	if (bits < 8 || bits > 64)
 61		return -EINVAL;
 62	else if (bits == 8)
 63		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
 64	else if (bits == 16)
 65		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
 66	else if (bits == 24)
 67		buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
 68	else if (bits <= 32)
 69		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 70	else
 71		buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
 72
 73	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 74		slave_config->direction = DMA_MEM_TO_DEV;
 75		slave_config->dst_addr_width = buswidth;
 76	} else {
 77		slave_config->direction = DMA_DEV_TO_MEM;
 78		slave_config->src_addr_width = buswidth;
 79	}
 80
 81	slave_config->device_fc = false;
 82
 83	return 0;
 84}
 85EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config);
 86
 87/**
 88 * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config
 89 *  using DAI DMA data.
 90 * @substream: PCM substream
 91 * @dma_data: DAI DMA data
 92 * @slave_config: DMA slave configuration
 93 *
 94 * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width and
 95 * slave_id fields of the DMA slave config from the same fields of the DAI DMA
 96 * data struct. The src and dst fields will be initialized depending on the
 97 * direction of the substream. If the substream is a playback stream the dst
 98 * fields will be initialized, if it is a capture stream the src fields will be
 99 * initialized. The {dst,src}_addr_width field will only be initialized if the
100 * SND_DMAENGINE_PCM_DAI_FLAG_PACK flag is set or if the addr_width field of
101 * the DAI DMA data struct is not equal to DMA_SLAVE_BUSWIDTH_UNDEFINED. If
102 * both conditions are met the latter takes priority.
103 */
104void snd_dmaengine_pcm_set_config_from_dai_data(
105	const struct snd_pcm_substream *substream,
106	const struct snd_dmaengine_dai_dma_data *dma_data,
107	struct dma_slave_config *slave_config)
108{
109	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
110		slave_config->dst_addr = dma_data->addr;
111		slave_config->dst_maxburst = dma_data->maxburst;
112		if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
113			slave_config->dst_addr_width =
114				DMA_SLAVE_BUSWIDTH_UNDEFINED;
115		if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
116			slave_config->dst_addr_width = dma_data->addr_width;
117	} else {
118		slave_config->src_addr = dma_data->addr;
119		slave_config->src_maxburst = dma_data->maxburst;
120		if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
121			slave_config->src_addr_width =
122				DMA_SLAVE_BUSWIDTH_UNDEFINED;
123		if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
124			slave_config->src_addr_width = dma_data->addr_width;
125	}
126
127	slave_config->slave_id = dma_data->slave_id;
128}
129EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data);
130
131static void dmaengine_pcm_dma_complete(void *arg)
132{
133	struct snd_pcm_substream *substream = arg;
134	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
135
136	prtd->pos += snd_pcm_lib_period_bytes(substream);
137	if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream))
138		prtd->pos = 0;
139
140	snd_pcm_period_elapsed(substream);
141}
142
143static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
144{
145	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
146	struct dma_chan *chan = prtd->dma_chan;
147	struct dma_async_tx_descriptor *desc;
148	enum dma_transfer_direction direction;
149	unsigned long flags = DMA_CTRL_ACK;
150
151	direction = snd_pcm_substream_to_dma_direction(substream);
152
153	if (!substream->runtime->no_period_wakeup)
154		flags |= DMA_PREP_INTERRUPT;
155
156	prtd->pos = 0;
157	desc = dmaengine_prep_dma_cyclic(chan,
158		substream->runtime->dma_addr,
159		snd_pcm_lib_buffer_bytes(substream),
160		snd_pcm_lib_period_bytes(substream), direction, flags);
161
162	if (!desc)
163		return -ENOMEM;
164
165	desc->callback = dmaengine_pcm_dma_complete;
166	desc->callback_param = substream;
167	prtd->cookie = dmaengine_submit(desc);
168
169	return 0;
170}
171
172/**
173 * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation
174 * @substream: PCM substream
175 * @cmd: Trigger command
176 *
177 * Returns 0 on success, a negative error code otherwise.
178 *
179 * This function can be used as the PCM trigger callback for dmaengine based PCM
180 * driver implementations.
181 */
182int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
183{
184	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
185	struct snd_pcm_runtime *runtime = substream->runtime;
186	int ret;
187
188	switch (cmd) {
189	case SNDRV_PCM_TRIGGER_START:
190		ret = dmaengine_pcm_prepare_and_submit(substream);
191		if (ret)
192			return ret;
193		dma_async_issue_pending(prtd->dma_chan);
194		break;
195	case SNDRV_PCM_TRIGGER_RESUME:
196	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
197		dmaengine_resume(prtd->dma_chan);
198		break;
199	case SNDRV_PCM_TRIGGER_SUSPEND:
200		if (runtime->info & SNDRV_PCM_INFO_PAUSE)
201			dmaengine_pause(prtd->dma_chan);
202		else
203			dmaengine_terminate_async(prtd->dma_chan);
204		break;
205	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
206		dmaengine_pause(prtd->dma_chan);
207		break;
208	case SNDRV_PCM_TRIGGER_STOP:
209		dmaengine_terminate_async(prtd->dma_chan);
210		break;
211	default:
212		return -EINVAL;
213	}
214
215	return 0;
216}
217EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger);
218
219/**
220 * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation
221 * @substream: PCM substream
222 *
223 * This function is deprecated and should not be used by new drivers, as its
224 * results may be unreliable.
225 */
226snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream)
227{
228	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
229	return bytes_to_frames(substream->runtime, prtd->pos);
230}
231EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue);
232
233/**
234 * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation
235 * @substream: PCM substream
236 *
237 * This function can be used as the PCM pointer callback for dmaengine based PCM
238 * driver implementations.
239 */
240snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
241{
242	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 
243	struct dma_tx_state state;
244	enum dma_status status;
245	unsigned int buf_size;
246	unsigned int pos = 0;
247
248	status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
249	if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {
250		buf_size = snd_pcm_lib_buffer_bytes(substream);
251		if (state.residue > 0 && state.residue <= buf_size)
252			pos = buf_size - state.residue;
 
 
 
253	}
254
255	return bytes_to_frames(substream->runtime, pos);
256}
257EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);
258
259/**
260 * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM
261 * @filter_fn: Filter function used to request the DMA channel
262 * @filter_data: Data passed to the DMA filter function
263 *
264 * Returns NULL or the requested DMA channel.
265 *
266 * This function request a DMA channel for usage with dmaengine PCM.
267 */
268struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
269	void *filter_data)
270{
271	dma_cap_mask_t mask;
272
273	dma_cap_zero(mask);
274	dma_cap_set(DMA_SLAVE, mask);
275	dma_cap_set(DMA_CYCLIC, mask);
276
277	return dma_request_channel(mask, filter_fn, filter_data);
278}
279EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);
280
281/**
282 * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream
283 * @substream: PCM substream
284 * @chan: DMA channel to use for data transfers
285 *
286 * Returns 0 on success, a negative error code otherwise.
287 *
288 * The function should usually be called from the pcm open callback. Note that
289 * this function will use private_data field of the substream's runtime. So it
290 * is not available to your pcm driver implementation.
291 */
292int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
293	struct dma_chan *chan)
294{
295	struct dmaengine_pcm_runtime_data *prtd;
296	int ret;
297
298	if (!chan)
299		return -ENXIO;
300
301	ret = snd_pcm_hw_constraint_integer(substream->runtime,
302					    SNDRV_PCM_HW_PARAM_PERIODS);
303	if (ret < 0)
304		return ret;
305
306	prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
307	if (!prtd)
308		return -ENOMEM;
309
310	prtd->dma_chan = chan;
311
312	substream->runtime->private_data = prtd;
313
314	return 0;
315}
316EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open);
317
318/**
319 * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel
320 * @substream: PCM substream
321 * @filter_fn: Filter function used to request the DMA channel
322 * @filter_data: Data passed to the DMA filter function
323 *
324 * Returns 0 on success, a negative error code otherwise.
325 *
326 * This function will request a DMA channel using the passed filter function and
327 * data. The function should usually be called from the pcm open callback. Note
328 * that this function will use private_data field of the substream's runtime. So
329 * it is not available to your pcm driver implementation.
330 */
331int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
332	dma_filter_fn filter_fn, void *filter_data)
333{
334	return snd_dmaengine_pcm_open(substream,
335		    snd_dmaengine_pcm_request_channel(filter_fn, filter_data));
336}
337EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
338
339/**
340 * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream
341 * @substream: PCM substream
342 */
343int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)
344{
345	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
346
347	dmaengine_synchronize(prtd->dma_chan);
348	kfree(prtd);
349
350	return 0;
351}
352EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);
353
354/**
355 * snd_dmaengine_pcm_release_chan_close - Close a dmaengine based PCM substream and release channel
356 * @substream: PCM substream
357 *
358 * Releases the DMA channel associated with the PCM substream.
359 */
360int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
361{
362	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
363
364	dmaengine_synchronize(prtd->dma_chan);
365	dma_release_channel(prtd->dma_chan);
366	kfree(prtd);
367
368	return 0;
369}
370EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
371
372MODULE_LICENSE("GPL");
v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Copyright (C) 2012, Analog Devices Inc.
  4 *	Author: Lars-Peter Clausen <lars@metafoo.de>
  5 *
  6 *  Based on:
  7 *	imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
  8 *	mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc.
  9 *	ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
 10 *		      Copyright (C) 2006 Applied Data Systems
 11 */
 12#include <linux/module.h>
 13#include <linux/init.h>
 14#include <linux/dmaengine.h>
 15#include <linux/slab.h>
 16#include <sound/pcm.h>
 17#include <sound/pcm_params.h>
 18#include <sound/soc.h>
 19
 20#include <sound/dmaengine_pcm.h>
 21
 22struct dmaengine_pcm_runtime_data {
 23	struct dma_chan *dma_chan;
 24	dma_cookie_t cookie;
 25
 26	unsigned int pos;
 27};
 28
 29static inline struct dmaengine_pcm_runtime_data *substream_to_prtd(
 30	const struct snd_pcm_substream *substream)
 31{
 32	return substream->runtime->private_data;
 33}
 34
 35struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream)
 36{
 37	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 38
 39	return prtd->dma_chan;
 40}
 41EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan);
 42
 43/**
 44 * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config
 45 * @substream: PCM substream
 46 * @params: hw_params
 47 * @slave_config: DMA slave config
 48 *
 49 * This function can be used to initialize a dma_slave_config from a substream
 50 * and hw_params in a dmaengine based PCM driver implementation.
 51 */
 52int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
 53	const struct snd_pcm_hw_params *params,
 54	struct dma_slave_config *slave_config)
 55{
 56	enum dma_slave_buswidth buswidth;
 57	int bits;
 58
 59	bits = params_physical_width(params);
 60	if (bits < 8 || bits > 64)
 61		return -EINVAL;
 62	else if (bits == 8)
 63		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
 64	else if (bits == 16)
 65		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
 66	else if (bits == 24)
 67		buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
 68	else if (bits <= 32)
 69		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 70	else
 71		buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
 72
 73	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 74		slave_config->direction = DMA_MEM_TO_DEV;
 75		slave_config->dst_addr_width = buswidth;
 76	} else {
 77		slave_config->direction = DMA_DEV_TO_MEM;
 78		slave_config->src_addr_width = buswidth;
 79	}
 80
 81	slave_config->device_fc = false;
 82
 83	return 0;
 84}
 85EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config);
 86
 87/**
 88 * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config
 89 *  using DAI DMA data.
 90 * @substream: PCM substream
 91 * @dma_data: DAI DMA data
 92 * @slave_config: DMA slave configuration
 93 *
 94 * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width and
 95 * slave_id fields of the DMA slave config from the same fields of the DAI DMA
 96 * data struct. The src and dst fields will be initialized depending on the
 97 * direction of the substream. If the substream is a playback stream the dst
 98 * fields will be initialized, if it is a capture stream the src fields will be
 99 * initialized. The {dst,src}_addr_width field will only be initialized if the
100 * SND_DMAENGINE_PCM_DAI_FLAG_PACK flag is set or if the addr_width field of
101 * the DAI DMA data struct is not equal to DMA_SLAVE_BUSWIDTH_UNDEFINED. If
102 * both conditions are met the latter takes priority.
103 */
104void snd_dmaengine_pcm_set_config_from_dai_data(
105	const struct snd_pcm_substream *substream,
106	const struct snd_dmaengine_dai_dma_data *dma_data,
107	struct dma_slave_config *slave_config)
108{
109	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
110		slave_config->dst_addr = dma_data->addr;
111		slave_config->dst_maxburst = dma_data->maxburst;
112		if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
113			slave_config->dst_addr_width =
114				DMA_SLAVE_BUSWIDTH_UNDEFINED;
115		if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
116			slave_config->dst_addr_width = dma_data->addr_width;
117	} else {
118		slave_config->src_addr = dma_data->addr;
119		slave_config->src_maxburst = dma_data->maxburst;
120		if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
121			slave_config->src_addr_width =
122				DMA_SLAVE_BUSWIDTH_UNDEFINED;
123		if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
124			slave_config->src_addr_width = dma_data->addr_width;
125	}
126
127	slave_config->slave_id = dma_data->slave_id;
128}
129EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data);
130
131static void dmaengine_pcm_dma_complete(void *arg)
132{
133	struct snd_pcm_substream *substream = arg;
134	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
135
136	prtd->pos += snd_pcm_lib_period_bytes(substream);
137	if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream))
138		prtd->pos = 0;
139
140	snd_pcm_period_elapsed(substream);
141}
142
143static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
144{
145	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
146	struct dma_chan *chan = prtd->dma_chan;
147	struct dma_async_tx_descriptor *desc;
148	enum dma_transfer_direction direction;
149	unsigned long flags = DMA_CTRL_ACK;
150
151	direction = snd_pcm_substream_to_dma_direction(substream);
152
153	if (!substream->runtime->no_period_wakeup)
154		flags |= DMA_PREP_INTERRUPT;
155
156	prtd->pos = 0;
157	desc = dmaengine_prep_dma_cyclic(chan,
158		substream->runtime->dma_addr,
159		snd_pcm_lib_buffer_bytes(substream),
160		snd_pcm_lib_period_bytes(substream), direction, flags);
161
162	if (!desc)
163		return -ENOMEM;
164
165	desc->callback = dmaengine_pcm_dma_complete;
166	desc->callback_param = substream;
167	prtd->cookie = dmaengine_submit(desc);
168
169	return 0;
170}
171
172/**
173 * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation
174 * @substream: PCM substream
175 * @cmd: Trigger command
176 *
177 * Returns 0 on success, a negative error code otherwise.
178 *
179 * This function can be used as the PCM trigger callback for dmaengine based PCM
180 * driver implementations.
181 */
182int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
183{
184	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
185	struct snd_pcm_runtime *runtime = substream->runtime;
186	int ret;
187
188	switch (cmd) {
189	case SNDRV_PCM_TRIGGER_START:
190		ret = dmaengine_pcm_prepare_and_submit(substream);
191		if (ret)
192			return ret;
193		dma_async_issue_pending(prtd->dma_chan);
194		break;
195	case SNDRV_PCM_TRIGGER_RESUME:
196	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
197		dmaengine_resume(prtd->dma_chan);
198		break;
199	case SNDRV_PCM_TRIGGER_SUSPEND:
200		if (runtime->info & SNDRV_PCM_INFO_PAUSE)
201			dmaengine_pause(prtd->dma_chan);
202		else
203			dmaengine_terminate_async(prtd->dma_chan);
204		break;
205	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
206		dmaengine_pause(prtd->dma_chan);
207		break;
208	case SNDRV_PCM_TRIGGER_STOP:
209		dmaengine_terminate_async(prtd->dma_chan);
210		break;
211	default:
212		return -EINVAL;
213	}
214
215	return 0;
216}
217EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger);
218
219/**
220 * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation
221 * @substream: PCM substream
222 *
223 * This function is deprecated and should not be used by new drivers, as its
224 * results may be unreliable.
225 */
226snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream)
227{
228	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
229	return bytes_to_frames(substream->runtime, prtd->pos);
230}
231EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue);
232
233/**
234 * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation
235 * @substream: PCM substream
236 *
237 * This function can be used as the PCM pointer callback for dmaengine based PCM
238 * driver implementations.
239 */
240snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
241{
242	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
243	struct snd_pcm_runtime *runtime = substream->runtime;
244	struct dma_tx_state state;
245	enum dma_status status;
246	unsigned int buf_size;
247	unsigned int pos = 0;
248
249	status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
250	if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {
251		buf_size = snd_pcm_lib_buffer_bytes(substream);
252		if (state.residue > 0 && state.residue <= buf_size)
253			pos = buf_size - state.residue;
254
255		runtime->delay = bytes_to_frames(runtime,
256						 state.in_flight_bytes);
257	}
258
259	return bytes_to_frames(runtime, pos);
260}
261EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);
262
263/**
264 * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM
265 * @filter_fn: Filter function used to request the DMA channel
266 * @filter_data: Data passed to the DMA filter function
267 *
268 * Returns NULL or the requested DMA channel.
269 *
270 * This function request a DMA channel for usage with dmaengine PCM.
271 */
272struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
273	void *filter_data)
274{
275	dma_cap_mask_t mask;
276
277	dma_cap_zero(mask);
278	dma_cap_set(DMA_SLAVE, mask);
279	dma_cap_set(DMA_CYCLIC, mask);
280
281	return dma_request_channel(mask, filter_fn, filter_data);
282}
283EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);
284
285/**
286 * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream
287 * @substream: PCM substream
288 * @chan: DMA channel to use for data transfers
289 *
290 * Returns 0 on success, a negative error code otherwise.
291 *
292 * The function should usually be called from the pcm open callback. Note that
293 * this function will use private_data field of the substream's runtime. So it
294 * is not available to your pcm driver implementation.
295 */
296int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
297	struct dma_chan *chan)
298{
299	struct dmaengine_pcm_runtime_data *prtd;
300	int ret;
301
302	if (!chan)
303		return -ENXIO;
304
305	ret = snd_pcm_hw_constraint_integer(substream->runtime,
306					    SNDRV_PCM_HW_PARAM_PERIODS);
307	if (ret < 0)
308		return ret;
309
310	prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
311	if (!prtd)
312		return -ENOMEM;
313
314	prtd->dma_chan = chan;
315
316	substream->runtime->private_data = prtd;
317
318	return 0;
319}
320EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open);
321
322/**
323 * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel
324 * @substream: PCM substream
325 * @filter_fn: Filter function used to request the DMA channel
326 * @filter_data: Data passed to the DMA filter function
327 *
328 * Returns 0 on success, a negative error code otherwise.
329 *
330 * This function will request a DMA channel using the passed filter function and
331 * data. The function should usually be called from the pcm open callback. Note
332 * that this function will use private_data field of the substream's runtime. So
333 * it is not available to your pcm driver implementation.
334 */
335int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
336	dma_filter_fn filter_fn, void *filter_data)
337{
338	return snd_dmaengine_pcm_open(substream,
339		    snd_dmaengine_pcm_request_channel(filter_fn, filter_data));
340}
341EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
342
343/**
344 * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream
345 * @substream: PCM substream
346 */
347int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)
348{
349	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
350
351	dmaengine_synchronize(prtd->dma_chan);
352	kfree(prtd);
353
354	return 0;
355}
356EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);
357
358/**
359 * snd_dmaengine_pcm_release_chan_close - Close a dmaengine based PCM substream and release channel
360 * @substream: PCM substream
361 *
362 * Releases the DMA channel associated with the PCM substream.
363 */
364int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
365{
366	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
367
368	dmaengine_synchronize(prtd->dma_chan);
369	dma_release_channel(prtd->dma_chan);
370	kfree(prtd);
371
372	return 0;
373}
374EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);
375
376/**
377 * snd_dmaengine_pcm_refine_runtime_hwparams - Refine runtime hw params
378 * @substream: PCM substream
379 * @dma_data: DAI DMA data
380 * @hw: PCM hw params
381 * @chan: DMA channel to use for data transfers
382 *
383 * Returns 0 on success, a negative error code otherwise.
384 *
385 * This function will query DMA capability, then refine the pcm hardware
386 * parameters.
387 */
388int snd_dmaengine_pcm_refine_runtime_hwparams(
389	struct snd_pcm_substream *substream,
390	struct snd_dmaengine_dai_dma_data *dma_data,
391	struct snd_pcm_hardware *hw,
392	struct dma_chan *chan)
393{
394	struct dma_slave_caps dma_caps;
395	u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
396			  BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
397			  BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
398	snd_pcm_format_t i;
399	int ret = 0;
400
401	if (!hw || !chan || !dma_data)
402		return -EINVAL;
403
404	ret = dma_get_slave_caps(chan, &dma_caps);
405	if (ret == 0) {
406		if (dma_caps.cmd_pause && dma_caps.cmd_resume)
407			hw->info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
408		if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT)
409			hw->info |= SNDRV_PCM_INFO_BATCH;
410
411		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
412			addr_widths = dma_caps.dst_addr_widths;
413		else
414			addr_widths = dma_caps.src_addr_widths;
415	}
416
417	/*
418	 * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep
419	 * hw.formats set to 0, meaning no restrictions are in place.
420	 * In this case it's the responsibility of the DAI driver to
421	 * provide the supported format information.
422	 */
423	if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK))
424		/*
425		 * Prepare formats mask for valid/allowed sample types. If the
426		 * dma does not have support for the given physical word size,
427		 * it needs to be masked out so user space can not use the
428		 * format which produces corrupted audio.
429		 * In case the dma driver does not implement the slave_caps the
430		 * default assumption is that it supports 1, 2 and 4 bytes
431		 * widths.
432		 */
433		pcm_for_each_format(i) {
434			int bits = snd_pcm_format_physical_width(i);
435
436			/*
437			 * Enable only samples with DMA supported physical
438			 * widths
439			 */
440			switch (bits) {
441			case 8:
442			case 16:
443			case 24:
444			case 32:
445			case 64:
446				if (addr_widths & (1 << (bits / 8)))
447					hw->formats |= pcm_format_to_bits(i);
448				break;
449			default:
450				/* Unsupported types */
451				break;
452			}
453		}
454
455	return ret;
456}
457EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_refine_runtime_hwparams);
458
459MODULE_LICENSE("GPL");