1/*
2 *  Copyright (C) 2012, Analog Devices Inc.
3 *	Author: Lars-Peter Clausen <lars@metafoo.de>
4 *
5 *  This program is free software; you can redistribute it and/or modify it
6 *  under  the terms of the GNU General  Public License as published by the
7 *  Free Software Foundation;  either version 2 of the License, or (at your
8 *  option) any later version.
9 *
10 *  You should have received a copy of the GNU General Public License along
11 *  with this program; if not, write to the Free Software Foundation, Inc.,
12 *  675 Mass Ave, Cambridge, MA 02139, USA.
13 *
14 */
15#ifndef __SOUND_DMAENGINE_PCM_H__
16#define __SOUND_DMAENGINE_PCM_H__
17
18#include <sound/pcm.h>
19#include <sound/soc.h>
20#include <linux/dmaengine.h>
21
22/**
23 * snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM
24 *   substream
25 * @substream: PCM substream
26 */
27static inline enum dma_transfer_direction
28snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
29{
30	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
31		return DMA_MEM_TO_DEV;
32	else
33		return DMA_DEV_TO_MEM;
34}
35
36int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
37	const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
38int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
39snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
40snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
41
42int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
43	struct dma_chan *chan);
44int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
45
46int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
47	dma_filter_fn filter_fn, void *filter_data);
48int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
49
50struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
51	void *filter_data);
52struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
53
54/**
55 * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
56 * @addr: Address of the DAI data source or destination register.
57 * @addr_width: Width of the DAI data source or destination register.
58 * @maxburst: Maximum number of words(note: words, as in units of the
59 * src_addr_width member, not bytes) that can be send to or received from the
60 * DAI in one burst.
61 * @slave_id: Slave requester id for the DMA channel.
62 * @filter_data: Custom DMA channel filter data, this will usually be used when
63 * requesting the DMA channel.
64 * @chan_name: Custom channel name to use when requesting DMA channel.
65 * @fifo_size: FIFO size of the DAI controller in bytes
66 */
67struct snd_dmaengine_dai_dma_data {
68	dma_addr_t addr;
69	enum dma_slave_buswidth addr_width;
70	u32 maxburst;
71	unsigned int slave_id;
72	void *filter_data;
73	const char *chan_name;
74	unsigned int fifo_size;
75};
76
77void snd_dmaengine_pcm_set_config_from_dai_data(
78	const struct snd_pcm_substream *substream,
79	const struct snd_dmaengine_dai_dma_data *dma_data,
80	struct dma_slave_config *config);
81
82
83/*
84 * Try to request the DMA channel using compat_request_channel or
85 * compat_filter_fn if it couldn't be requested through devicetree.
86 */
87#define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
88/*
89 * Don't try to request the DMA channels through devicetree. This flag only
90 * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
91 */
92#define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
93/*
94 * The platforms dmaengine driver does not support reporting the amount of
95 * bytes that are still left to transfer.
96 */
97#define SND_DMAENGINE_PCM_FLAG_NO_RESIDUE BIT(2)
98/*
99 * The PCM is half duplex and the DMA channel is shared between capture and
100 * playback.
101 */
102#define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
103/*
104 * The PCM streams have custom channel names specified.
105 */
106#define SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME BIT(4)
107
108/**
109 * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
110 * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
111 *   PCM substream. Will be called from the PCM drivers hwparams callback.
112 * @compat_request_channel: Callback to request a DMA channel for platforms
113 *   which do not use devicetree.
114 * @compat_filter_fn: Will be used as the filter function when requesting a
115 *  channel for platforms which do not use devicetree. The filter parameter
116 *  will be the DAI's DMA data.
117 * @dma_dev: If set, request DMA channel on this device rather than the DAI
118 *  device.
119 * @chan_names: If set, these custom DMA channel names will be requested at
120 *  registration time.
121 * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
122 * @prealloc_buffer_size: Size of the preallocated audio buffer.
123 *
124 * Note: If both compat_request_channel and compat_filter_fn are set
125 * compat_request_channel will be used to request the channel and
126 * compat_filter_fn will be ignored. Otherwise the channel will be requested
127 * using dma_request_channel with compat_filter_fn as the filter function.
128 */
129struct snd_dmaengine_pcm_config {
130	int (*prepare_slave_config)(struct snd_pcm_substream *substream,
131			struct snd_pcm_hw_params *params,
132			struct dma_slave_config *slave_config);
133	struct dma_chan *(*compat_request_channel)(
134			struct snd_soc_pcm_runtime *rtd,
135			struct snd_pcm_substream *substream);
136	dma_filter_fn compat_filter_fn;
137	struct device *dma_dev;
138	const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
139
140	const struct snd_pcm_hardware *pcm_hardware;
141	unsigned int prealloc_buffer_size;
142};
143
144int snd_dmaengine_pcm_register(struct device *dev,
145	const struct snd_dmaengine_pcm_config *config,
146	unsigned int flags);
147void snd_dmaengine_pcm_unregister(struct device *dev);
148
149int devm_snd_dmaengine_pcm_register(struct device *dev,
150	const struct snd_dmaengine_pcm_config *config,
151	unsigned int flags);
152
153int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
154	struct snd_pcm_hw_params *params,
155	struct dma_slave_config *slave_config);
156
157#endif
158