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
40 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
41 dma_filter_fn filter_fn, void *filter_data);
42 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
43
44 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
45 void *filter_data);
46 struct 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 */
74 struct 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
86 void 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
91 int 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 * @name: Component name. If null, dev_name will be used.
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 const char *name;
148 dma_filter_fn compat_filter_fn;
149 struct device *dma_dev;
150 const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
151
152 const struct snd_pcm_hardware *pcm_hardware;
153 unsigned int prealloc_buffer_size;
154 };
155
156 int snd_dmaengine_pcm_register(struct device *dev,
157 const struct snd_dmaengine_pcm_config *config,
158 unsigned int flags);
159 void snd_dmaengine_pcm_unregister(struct device *dev);
160
161 int devm_snd_dmaengine_pcm_register(struct device *dev,
162 const struct snd_dmaengine_pcm_config *config,
163 unsigned int flags);
164
165 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
166 struct snd_pcm_hw_params *params,
167 struct dma_slave_config *slave_config);
168
169 #define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
170
171 struct dmaengine_pcm {
172 struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
173 const struct snd_dmaengine_pcm_config *config;
174 struct snd_soc_component component;
175 unsigned int flags;
176 };
177
soc_component_to_pcm(struct snd_soc_component * p)178 static inline struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
179 {
180 return container_of(p, struct dmaengine_pcm, component);
181 }
182 #endif
183