1/* SPDX-License-Identifier: GPL-2.0+
  2 *
  3 *  Copyright (C) 2012, Analog Devices Inc.
  4 *	Author: Lars-Peter Clausen <lars@metafoo.de>
  5 */
  6
  7#ifndef __SOUND_DMAENGINE_PCM_H__
  8#define __SOUND_DMAENGINE_PCM_H__
  9
 10#include <sound/pcm.h>
 11#include <sound/soc.h>
 12#include <linux/dmaengine.h>
 13
 14/**
 15 * snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM
 16 *   substream
 17 * @substream: PCM substream
 18 *
 19 * Return: DMA transfer direction
 20 */
 21static inline enum dma_transfer_direction
 22snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
 23{
 24	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 25		return DMA_MEM_TO_DEV;
 26	else
 27		return DMA_DEV_TO_MEM;
 28}
 29
 30int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
 31	const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
 32int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
 33snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
 34snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
 35
 36int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
 37	struct dma_chan *chan);
 38int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
 39
 40int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
 41	dma_filter_fn filter_fn, void *filter_data);
 42int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
 43
 44struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
 45	void *filter_data);
 46struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
 47
 48/*
 49 * The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word.
 50 * If this flag is set the dmaengine driver won't put any restriction on
 51 * the supported sample formats and set the DMA transfer size to undefined.
 52 * The DAI driver is responsible to disable any unsupported formats in it's
 53 * configuration and catch corner cases that are not already handled in
 54 * the ALSA core.
 55 */
 56#define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0)
 57
 58/**
 59 * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
 60 * @addr: Address of the DAI data source or destination register.
 61 * @addr_width: Width of the DAI data source or destination register.
 62 * @maxburst: Maximum number of words(note: words, as in units of the
 63 * src_addr_width member, not bytes) that can be send to or received from the
 64 * DAI in one burst.
 65 * @filter_data: Custom DMA channel filter data, this will usually be used when
 66 * requesting the DMA channel.
 67 * @chan_name: Custom channel name to use when requesting DMA channel.
 68 * @fifo_size: FIFO size of the DAI controller in bytes
 69 * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now
 70 * @peripheral_config: peripheral configuration for programming peripheral
 71 * for dmaengine transfer
 72 * @peripheral_size: peripheral configuration buffer size
 73 */
 74struct snd_dmaengine_dai_dma_data {
 75	dma_addr_t addr;
 76	enum dma_slave_buswidth addr_width;
 77	u32 maxburst;
 78	void *filter_data;
 79	const char *chan_name;
 80	unsigned int fifo_size;
 81	unsigned int flags;
 82	void *peripheral_config;
 83	size_t peripheral_size;
 84};
 85
 86void snd_dmaengine_pcm_set_config_from_dai_data(
 87	const struct snd_pcm_substream *substream,
 88	const struct snd_dmaengine_dai_dma_data *dma_data,
 89	struct dma_slave_config *config);
 90
 91int snd_dmaengine_pcm_refine_runtime_hwparams(
 92	struct snd_pcm_substream *substream,
 93	struct snd_dmaengine_dai_dma_data *dma_data,
 94	struct snd_pcm_hardware *hw,
 95	struct dma_chan *chan);
 96
 97/*
 98 * Try to request the DMA channel using compat_request_channel or
 99 * compat_filter_fn if it couldn't be requested through devicetree.
100 */
101#define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
102/*
103 * Don't try to request the DMA channels through devicetree. This flag only
104 * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
105 */
106#define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
107/*
108 * The PCM is half duplex and the DMA channel is shared between capture and
109 * playback.
110 */
111#define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
112
113/**
114 * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
115 * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
116 *   PCM substream. Will be called from the PCM drivers hwparams callback.
117 * @compat_request_channel: Callback to request a DMA channel for platforms
118 *   which do not use devicetree.
119 * @process: Callback used to apply processing on samples transferred from/to
120 *   user space.
121 * @compat_filter_fn: Will be used as the filter function when requesting a
122 *  channel for platforms which do not use devicetree. The filter parameter
123 *  will be the DAI's DMA data.
124 * @dma_dev: If set, request DMA channel on this device rather than the DAI
125 *  device.
126 * @chan_names: If set, these custom DMA channel names will be requested at
127 *  registration time.
128 * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
129 * @prealloc_buffer_size: Size of the preallocated audio buffer.
130 *
131 * Note: If both compat_request_channel and compat_filter_fn are set
132 * compat_request_channel will be used to request the channel and
133 * compat_filter_fn will be ignored. Otherwise the channel will be requested
134 * using dma_request_channel with compat_filter_fn as the filter function.
135 */
136struct snd_dmaengine_pcm_config {
137	int (*prepare_slave_config)(struct snd_pcm_substream *substream,
138			struct snd_pcm_hw_params *params,
139			struct dma_slave_config *slave_config);
140	struct dma_chan *(*compat_request_channel)(
141			struct snd_soc_pcm_runtime *rtd,
142			struct snd_pcm_substream *substream);
143	int (*process)(struct snd_pcm_substream *substream,
144		       int channel, unsigned long hwoff,
145		       unsigned long bytes);
146	dma_filter_fn compat_filter_fn;
147	struct device *dma_dev;
148	const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
149
150	const struct snd_pcm_hardware *pcm_hardware;
151	unsigned int prealloc_buffer_size;
152};
153
154int snd_dmaengine_pcm_register(struct device *dev,
155	const struct snd_dmaengine_pcm_config *config,
156	unsigned int flags);
157void snd_dmaengine_pcm_unregister(struct device *dev);
158
159int devm_snd_dmaengine_pcm_register(struct device *dev,
160	const struct snd_dmaengine_pcm_config *config,
161	unsigned int flags);
162
163int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
164	struct snd_pcm_hw_params *params,
165	struct dma_slave_config *slave_config);
166
167#define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
168
169struct dmaengine_pcm {
170	struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
171	const struct snd_dmaengine_pcm_config *config;
172	struct snd_soc_component component;
173	unsigned int flags;
174};
175
176static inline struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
177{
178	return container_of(p, struct dmaengine_pcm, component);
179}
180#endif