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 * @name: Component name. If null, dev_name will be used.
123 * @compat_filter_fn: Will be used as the filter function when requesting a
124 * channel for platforms which do not use devicetree. The filter parameter
125 * will be the DAI's DMA data.
126 * @dma_dev: If set, request DMA channel on this device rather than the DAI
127 * device.
128 * @chan_names: If set, these custom DMA channel names will be requested at
129 * registration time.
130 * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
131 * @prealloc_buffer_size: Size of the preallocated audio buffer.
132 *
133 * Note: If both compat_request_channel and compat_filter_fn are set
134 * compat_request_channel will be used to request the channel and
135 * compat_filter_fn will be ignored. Otherwise the channel will be requested
136 * using dma_request_channel with compat_filter_fn as the filter function.
137 */
138 struct snd_dmaengine_pcm_config {
139 int (*prepare_slave_config)(struct snd_pcm_substream *substream,
140 struct snd_pcm_hw_params *params,
141 struct dma_slave_config *slave_config);
142 struct dma_chan *(*compat_request_channel)(
143 struct snd_soc_pcm_runtime *rtd,
144 struct snd_pcm_substream *substream);
145 int (*process)(struct snd_pcm_substream *substream,
146 int channel, unsigned long hwoff,
147 unsigned long bytes);
148 const char *name;
149 dma_filter_fn compat_filter_fn;
150 struct device *dma_dev;
151 const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
152
153 const struct snd_pcm_hardware *pcm_hardware;
154 unsigned int prealloc_buffer_size;
155 };
156
157 int snd_dmaengine_pcm_register(struct device *dev,
158 const struct snd_dmaengine_pcm_config *config,
159 unsigned int flags);
160 void snd_dmaengine_pcm_unregister(struct device *dev);
161
162 int devm_snd_dmaengine_pcm_register(struct device *dev,
163 const struct snd_dmaengine_pcm_config *config,
164 unsigned int flags);
165
166 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
167 struct snd_pcm_hw_params *params,
168 struct dma_slave_config *slave_config);
169
170 #define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
171
172 struct dmaengine_pcm {
173 struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
174 const struct snd_dmaengine_pcm_config *config;
175 struct snd_soc_component component;
176 unsigned int flags;
177 };
178
179 static inline struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
180 {
181 return container_of(p, struct dmaengine_pcm, component);
182 }
183 #endif
184
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