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
snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream * substream)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_close_release_chan(struct snd_pcm_substream *substream);
42
43 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
44 void *filter_data);
45 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
46
47 /*
48 * The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word.
49 * If this flag is set the dmaengine driver won't put any restriction on
50 * the supported sample formats and set the DMA transfer size to undefined.
51 * The DAI driver is responsible to disable any unsupported formats in it's
52 * configuration and catch corner cases that are not already handled in
53 * the ALSA core.
54 */
55 #define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0)
56
57 /**
58 * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
59 * @addr: Address of the DAI data source or destination register.
60 * @addr_width: Width of the DAI data source or destination register.
61 * @maxburst: Maximum number of words(note: words, as in units of the
62 * src_addr_width member, not bytes) that can be send to or received from the
63 * DAI in one burst.
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 * @peripheral_config: peripheral configuration for programming peripheral
70 * for dmaengine transfer
71 * @peripheral_size: peripheral configuration buffer size
72 */
73 struct snd_dmaengine_dai_dma_data {
74 dma_addr_t addr;
75 enum dma_slave_buswidth addr_width;
76 u32 maxburst;
77 void *filter_data;
78 const char *chan_name;
79 unsigned int fifo_size;
80 unsigned int flags;
81 void *peripheral_config;
82 size_t peripheral_size;
83 };
84
85 void snd_dmaengine_pcm_set_config_from_dai_data(
86 const struct snd_pcm_substream *substream,
87 const struct snd_dmaengine_dai_dma_data *dma_data,
88 struct dma_slave_config *config);
89
90 int snd_dmaengine_pcm_refine_runtime_hwparams(
91 struct snd_pcm_substream *substream,
92 struct snd_dmaengine_dai_dma_data *dma_data,
93 struct snd_pcm_hardware *hw,
94 struct dma_chan *chan);
95
96 /*
97 * Try to request the DMA channel using compat_request_channel or
98 * compat_filter_fn if it couldn't be requested through devicetree.
99 */
100 #define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
101 /*
102 * Don't try to request the DMA channels through devicetree. This flag only
103 * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
104 */
105 #define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
106 /*
107 * The PCM is half duplex and the DMA channel is shared between capture and
108 * playback.
109 */
110 #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
111
112 /**
113 * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
114 * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
115 * PCM substream. Will be called from the PCM drivers hwparams callback.
116 * @compat_request_channel: Callback to request a DMA channel for platforms
117 * which do not use devicetree.
118 * @process: Callback used to apply processing on samples transferred from/to
119 * user space.
120 * @name: Component name. If null, dev_name will be used.
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 */
136 struct 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 const char *name;
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
soc_component_to_pcm(struct snd_soc_component * p)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