1 /*
2  *  compress_driver.h - compress offload driver definations
3  *
4  *  Copyright (C) 2011 Intel Corporation
5  *  Authors:	Vinod Koul <vinod.koul@linux.intel.com>
6  *		Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
7  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; version 2 of the License.
12  *
13  *  This program is distributed in the hope that it will be useful, but
14  *  WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  *  General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License along
19  *  with this program; if not, write to the Free Software Foundation, Inc.,
20  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21  *
22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23  *
24  */
25 #ifndef __COMPRESS_DRIVER_H
26 #define __COMPRESS_DRIVER_H
27 
28 #include <linux/types.h>
29 #include <linux/sched.h>
30 #include <sound/compress_offload.h>
31 #include <sound/asound.h>
32 #include <sound/pcm.h>
33 
34 struct snd_compr_ops;
35 
36 /**
37  * struct snd_compr_runtime: runtime stream description
38  * @state: stream state
39  * @ops: pointer to DSP callbacks
40  * @buffer: pointer to kernel buffer, valid only when not in mmap mode or
41  *	DSP doesn't implement copy
42  * @buffer_size: size of the above buffer
43  * @fragment_size: size of buffer fragment in bytes
44  * @fragments: number of such fragments
45  * @hw_pointer: offset of last location in buffer where DSP copied data
46  * @app_pointer: offset of last location in buffer where app wrote data
47  * @total_bytes_available: cumulative number of bytes made available in
48  *	the ring buffer
49  * @total_bytes_transferred: cumulative bytes transferred by offload DSP
50  * @sleep: poll sleep
51  */
52 struct snd_compr_runtime {
53 	snd_pcm_state_t state;
54 	struct snd_compr_ops *ops;
55 	void *buffer;
56 	u64 buffer_size;
57 	u32 fragment_size;
58 	u32 fragments;
59 	u64 hw_pointer;
60 	u64 app_pointer;
61 	u64 total_bytes_available;
62 	u64 total_bytes_transferred;
63 	wait_queue_head_t sleep;
64 	void *private_data;
65 };
66 
67 /**
68  * struct snd_compr_stream: compressed stream
69  * @name: device name
70  * @ops: pointer to DSP callbacks
71  * @runtime: pointer to runtime structure
72  * @device: device pointer
73  * @direction: stream direction, playback/recording
74  * @private_data: pointer to DSP private data
75  */
76 struct snd_compr_stream {
77 	const char *name;
78 	struct snd_compr_ops *ops;
79 	struct snd_compr_runtime *runtime;
80 	struct snd_compr *device;
81 	enum snd_compr_direction direction;
82 	void *private_data;
83 };
84 
85 /**
86  * struct snd_compr_ops: compressed path DSP operations
87  * @open: Open the compressed stream
88  * This callback is mandatory and shall keep dsp ready to receive the stream
89  * parameter
90  * @free: Close the compressed stream, mandatory
91  * @set_params: Sets the compressed stream parameters, mandatory
92  * This can be called in during stream creation only to set codec params
93  * and the stream properties
94  * @get_params: retrieve the codec parameters, mandatory
95  * @trigger: Trigger operations like start, pause, resume, drain, stop.
96  * This callback is mandatory
97  * @pointer: Retrieve current h/w pointer information. Mandatory
98  * @copy: Copy the compressed data to/from userspace, Optional
99  * Can't be implemented if DSP supports mmap
100  * @mmap: DSP mmap method to mmap DSP memory
101  * @ack: Ack for DSP when data is written to audio buffer, Optional
102  * Not valid if copy is implemented
103  * @get_caps: Retrieve DSP capabilities, mandatory
104  * @get_codec_caps: Retrieve capabilities for a specific codec, mandatory
105  */
106 struct snd_compr_ops {
107 	int (*open)(struct snd_compr_stream *stream);
108 	int (*free)(struct snd_compr_stream *stream);
109 	int (*set_params)(struct snd_compr_stream *stream,
110 			struct snd_compr_params *params);
111 	int (*get_params)(struct snd_compr_stream *stream,
112 			struct snd_codec *params);
113 	int (*trigger)(struct snd_compr_stream *stream, int cmd);
114 	int (*pointer)(struct snd_compr_stream *stream,
115 			struct snd_compr_tstamp *tstamp);
116 	int (*copy)(struct snd_compr_stream *stream, const char __user *buf,
117 		       size_t count);
118 	int (*mmap)(struct snd_compr_stream *stream,
119 			struct vm_area_struct *vma);
120 	int (*ack)(struct snd_compr_stream *stream, size_t bytes);
121 	int (*get_caps) (struct snd_compr_stream *stream,
122 			struct snd_compr_caps *caps);
123 	int (*get_codec_caps) (struct snd_compr_stream *stream,
124 			struct snd_compr_codec_caps *codec);
125 };
126 
127 /**
128  * struct snd_compr: Compressed device
129  * @name: DSP device name
130  * @dev: Device pointer
131  * @ops: pointer to DSP callbacks
132  * @private_data: pointer to DSP pvt data
133  * @card: sound card pointer
134  * @direction: Playback or capture direction
135  * @lock: device lock
136  * @device: device id
137  */
138 struct snd_compr {
139 	const char *name;
140 	struct device *dev;
141 	struct snd_compr_ops *ops;
142 	void *private_data;
143 	struct snd_card *card;
144 	unsigned int direction;
145 	struct mutex lock;
146 	int device;
147 };
148 
149 /* compress device register APIs */
150 int snd_compress_register(struct snd_compr *device);
151 int snd_compress_deregister(struct snd_compr *device);
152 int snd_compress_new(struct snd_card *card, int device,
153 			int type, struct snd_compr *compr);
154 
155 /* dsp driver callback apis
156  * For playback: driver should call snd_compress_fragment_elapsed() to let the
157  * framework know that a fragment has been consumed from the ring buffer
158  *
159  * For recording: we want to know when a frame is available or when
160  * at least one frame is available so snd_compress_frame_elapsed()
161  * callback should be called when a encodeded frame is available
162  */
163 static inline void snd_compr_fragment_elapsed(struct snd_compr_stream *stream)
164 {
165 	wake_up(&stream->runtime->sleep);
166 }
167 
168 #endif
169