xref: /openbmc/linux/include/sound/dmaengine_pcm.h (revision d5a9588c)
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  */
21 static inline enum dma_transfer_direction
22 snd_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 
30 int 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);
32 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
33 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
34 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
35 
36 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
37 	struct dma_chan *chan);
38 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
39 int snd_dmaengine_pcm_sync_stop(struct snd_pcm_substream *substream);
40 
41 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
42 	dma_filter_fn filter_fn, void *filter_data);
43 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
44 
45 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
46 	void *filter_data);
47 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
48 
49 /*
50  * The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word.
51  * If this flag is set the dmaengine driver won't put any restriction on
52  * the supported sample formats and set the DMA transfer size to undefined.
53  * The DAI driver is responsible to disable any unsupported formats in it's
54  * configuration and catch corner cases that are not already handled in
55  * the ALSA core.
56  */
57 #define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0)
58 
59 /**
60  * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
61  * @addr: Address of the DAI data source or destination register.
62  * @addr_width: Width of the DAI data source or destination register.
63  * @maxburst: Maximum number of words(note: words, as in units of the
64  * src_addr_width member, not bytes) that can be send to or received from the
65  * DAI in one burst.
66  * @filter_data: Custom DMA channel filter data, this will usually be used when
67  * requesting the DMA channel.
68  * @chan_name: Custom channel name to use when requesting DMA channel.
69  * @fifo_size: FIFO size of the DAI controller in bytes
70  * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now
71  * @peripheral_config: peripheral configuration for programming peripheral
72  * for dmaengine transfer
73  * @peripheral_size: peripheral configuration buffer size
74  */
75 struct snd_dmaengine_dai_dma_data {
76 	dma_addr_t addr;
77 	enum dma_slave_buswidth addr_width;
78 	u32 maxburst;
79 	void *filter_data;
80 	const char *chan_name;
81 	unsigned int fifo_size;
82 	unsigned int flags;
83 	void *peripheral_config;
84 	size_t peripheral_size;
85 };
86 
87 void snd_dmaengine_pcm_set_config_from_dai_data(
88 	const struct snd_pcm_substream *substream,
89 	const struct snd_dmaengine_dai_dma_data *dma_data,
90 	struct dma_slave_config *config);
91 
92 int snd_dmaengine_pcm_refine_runtime_hwparams(
93 	struct snd_pcm_substream *substream,
94 	struct snd_dmaengine_dai_dma_data *dma_data,
95 	struct snd_pcm_hardware *hw,
96 	struct dma_chan *chan);
97 
98 /*
99  * Try to request the DMA channel using compat_request_channel or
100  * compat_filter_fn if it couldn't be requested through devicetree.
101  */
102 #define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
103 /*
104  * Don't try to request the DMA channels through devicetree. This flag only
105  * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
106  */
107 #define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
108 /*
109  * The PCM is half duplex and the DMA channel is shared between capture and
110  * playback.
111  */
112 #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
113 
114 /**
115  * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
116  * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
117  *   PCM substream. Will be called from the PCM drivers hwparams callback.
118  * @compat_request_channel: Callback to request a DMA channel for platforms
119  *   which do not use devicetree.
120  * @process: Callback used to apply processing on samples transferred from/to
121  *   user space.
122  * @compat_filter_fn: Will be used as the filter function when requesting a
123  *  channel for platforms which do not use devicetree. The filter parameter
124  *  will be the DAI's DMA data.
125  * @dma_dev: If set, request DMA channel on this device rather than the DAI
126  *  device.
127  * @chan_names: If set, these custom DMA channel names will be requested at
128  *  registration time.
129  * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
130  * @prealloc_buffer_size: Size of the preallocated audio buffer.
131  *
132  * Note: If both compat_request_channel and compat_filter_fn are set
133  * compat_request_channel will be used to request the channel and
134  * compat_filter_fn will be ignored. Otherwise the channel will be requested
135  * using dma_request_channel with compat_filter_fn as the filter function.
136  */
137 struct snd_dmaengine_pcm_config {
138 	int (*prepare_slave_config)(struct snd_pcm_substream *substream,
139 			struct snd_pcm_hw_params *params,
140 			struct dma_slave_config *slave_config);
141 	struct dma_chan *(*compat_request_channel)(
142 			struct snd_soc_pcm_runtime *rtd,
143 			struct snd_pcm_substream *substream);
144 	int (*process)(struct snd_pcm_substream *substream,
145 		       int channel, unsigned long hwoff,
146 		       unsigned long bytes);
147 	dma_filter_fn compat_filter_fn;
148 	struct device *dma_dev;
149 	const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
150 
151 	const struct snd_pcm_hardware *pcm_hardware;
152 	unsigned int prealloc_buffer_size;
153 };
154 
155 int snd_dmaengine_pcm_register(struct device *dev,
156 	const struct snd_dmaengine_pcm_config *config,
157 	unsigned int flags);
158 void snd_dmaengine_pcm_unregister(struct device *dev);
159 
160 int devm_snd_dmaengine_pcm_register(struct device *dev,
161 	const struct snd_dmaengine_pcm_config *config,
162 	unsigned int flags);
163 
164 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
165 	struct snd_pcm_hw_params *params,
166 	struct dma_slave_config *slave_config);
167 
168 #define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
169 
170 struct dmaengine_pcm {
171 	struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
172 	const struct snd_dmaengine_pcm_config *config;
173 	struct snd_soc_component component;
174 	unsigned int flags;
175 };
176 
177 static inline struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
178 {
179 	return container_of(p, struct dmaengine_pcm, component);
180 }
181 #endif
182