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