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 * @port_window_size: The length of the register area in words the data need
73 * to be accessed on the device side. It is only used for devices which is using
74 * an area instead of a single register to send/receive the data. Typically the
75 * DMA loops in this area in order to transfer the data.
76 */
77 struct snd_dmaengine_dai_dma_data {
78 dma_addr_t addr;
79 enum dma_slave_buswidth addr_width;
80 u32 maxburst;
81 void *filter_data;
82 const char *chan_name;
83 unsigned int fifo_size;
84 unsigned int flags;
85 void *peripheral_config;
86 size_t peripheral_size;
87 u32 port_window_size;
88 };
89
90 void snd_dmaengine_pcm_set_config_from_dai_data(
91 const struct snd_pcm_substream *substream,
92 const struct snd_dmaengine_dai_dma_data *dma_data,
93 struct dma_slave_config *config);
94
95 int snd_dmaengine_pcm_refine_runtime_hwparams(
96 struct snd_pcm_substream *substream,
97 struct snd_dmaengine_dai_dma_data *dma_data,
98 struct snd_pcm_hardware *hw,
99 struct dma_chan *chan);
100
101 /*
102 * Try to request the DMA channel using compat_request_channel or
103 * compat_filter_fn if it couldn't be requested through devicetree.
104 */
105 #define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
106 /*
107 * Don't try to request the DMA channels through devicetree. This flag only
108 * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
109 */
110 #define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
111 /*
112 * The PCM is half duplex and the DMA channel is shared between capture and
113 * playback.
114 */
115 #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
116
117 /**
118 * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
119 * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
120 * PCM substream. Will be called from the PCM drivers hwparams callback.
121 * @compat_request_channel: Callback to request a DMA channel for platforms
122 * which do not use devicetree.
123 * @process: Callback used to apply processing on samples transferred from/to
124 * user space.
125 * @name: Component name. If null, dev_name will be used.
126 * @compat_filter_fn: Will be used as the filter function when requesting a
127 * channel for platforms which do not use devicetree. The filter parameter
128 * will be the DAI's DMA data.
129 * @dma_dev: If set, request DMA channel on this device rather than the DAI
130 * device.
131 * @chan_names: If set, these custom DMA channel names will be requested at
132 * registration time.
133 * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
134 * @prealloc_buffer_size: Size of the preallocated audio buffer.
135 *
136 * Note: If both compat_request_channel and compat_filter_fn are set
137 * compat_request_channel will be used to request the channel and
138 * compat_filter_fn will be ignored. Otherwise the channel will be requested
139 * using dma_request_channel with compat_filter_fn as the filter function.
140 */
141 struct snd_dmaengine_pcm_config {
142 int (*prepare_slave_config)(struct snd_pcm_substream *substream,
143 struct snd_pcm_hw_params *params,
144 struct dma_slave_config *slave_config);
145 struct dma_chan *(*compat_request_channel)(
146 struct snd_soc_pcm_runtime *rtd,
147 struct snd_pcm_substream *substream);
148 int (*process)(struct snd_pcm_substream *substream,
149 int channel, unsigned long hwoff,
150 unsigned long bytes);
151 const char *name;
152 dma_filter_fn compat_filter_fn;
153 struct device *dma_dev;
154 const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
155
156 const struct snd_pcm_hardware *pcm_hardware;
157 unsigned int prealloc_buffer_size;
158 };
159
160 int snd_dmaengine_pcm_register(struct device *dev,
161 const struct snd_dmaengine_pcm_config *config,
162 unsigned int flags);
163 void snd_dmaengine_pcm_unregister(struct device *dev);
164
165 int devm_snd_dmaengine_pcm_register(struct device *dev,
166 const struct snd_dmaengine_pcm_config *config,
167 unsigned int flags);
168
169 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
170 struct snd_pcm_hw_params *params,
171 struct dma_slave_config *slave_config);
172
173 #define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
174
175 struct dmaengine_pcm {
176 struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
177 const struct snd_dmaengine_pcm_config *config;
178 struct snd_soc_component component;
179 unsigned int flags;
180 };
181
soc_component_to_pcm(struct snd_soc_component * p)182 static inline struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
183 {
184 return container_of(p, struct dmaengine_pcm, component);
185 }
186 #endif
187