1 /* Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
2 * Use of this source code is governed by a BSD-style license that can be
3 * found in the LICENSE file.
4 *
5 * The dev_stream structure is used for mapping streams to a device. In
6 * addition to the rstream, other mixing information is stored here.
7 */
8
9 #ifndef DEV_STREAM_H_
10 #define DEV_STREAM_H_
11
12 #include <stdint.h>
13 #include <sys/time.h>
14
15 #include "cras_types.h"
16 #include "cras_rstream.h"
17
18 struct cras_audio_area;
19 struct cras_fmt_conv;
20 struct cras_iodev;
21
22 /*
23 * Linked list of streams of audio from/to a client.
24 * Args:
25 * dev_id - Index of the hw device.
26 * stream - The rstream attached to a device.
27 * conv - Sample rate or format converter.
28 * conv_buffer - The buffer for converter if needed.
29 * conv_buffer_size_frames - Size of conv_buffer in frames.
30 * dev_rate - Sampling rate of device. This is set when dev_stream is
31 * created.
32 */
33 struct dev_stream {
34 unsigned int dev_id;
35 struct cras_rstream *stream;
36 struct cras_fmt_conv *conv;
37 struct byte_buffer *conv_buffer;
38 struct cras_audio_area *conv_area;
39 unsigned int conv_buffer_size_frames;
40 size_t dev_rate;
41 struct dev_stream *prev, *next;
42 };
43
44 struct dev_stream *dev_stream_create(struct cras_rstream *stream,
45 unsigned int dev_id,
46 const struct cras_audio_format *dev_fmt,
47 void *dev_ptr, struct timespec *cb_ts);
48 void dev_stream_destroy(struct dev_stream *dev_stream);
49
50 /*
51 * Update the estimated sample rate of the device. For multiple active
52 * devices case, the linear resampler will be configured by the estimated
53 * rate ration of the master device and the current active device the
54 * rstream attaches to.
55 *
56 * Args:
57 * dev_stream - The structure holding the stream.
58 * dev_rate - The sample rate device is using.
59 * dev_rate_ratio - The ratio of estimated rate and used rate.
60 * master_rate_ratio - The ratio of estimated rate and used rate of
61 * master device.
62 * coarse_rate_adjust - The flag to indicate the direction device
63 * sample rate should adjust to.
64 */
65 void dev_stream_set_dev_rate(struct dev_stream *dev_stream,
66 unsigned int dev_rate,
67 double dev_rate_ratio,
68 double master_rate_ratio,
69 int coarse_rate_adjust);
70
71 /*
72 * Renders count frames from shm into dst. Updates count if anything is
73 * written. If it's muted and the only stream zero memory.
74 * Args:
75 * dev_stream - The struct holding the stream to mix.
76 * format - The format of the audio device.
77 * dst - The destination buffer for mixing.
78 * num_to_write - The number of frames written.
79 */
80 int dev_stream_mix(struct dev_stream *dev_stream,
81 const struct cras_audio_format *fmt,
82 uint8_t *dst,
83 unsigned int num_to_write);
84
85 /*
86 * Reads froms from the source into the dev_stream.
87 * Args:
88 * dev_stream - The struct holding the stream to mix to.
89 * area - The area to copy audio from.
90 * area_offset - The offset at which to start reading from area.
91 * software_gain_scaler - The software gain scaler.
92 */
93 unsigned int dev_stream_capture(struct dev_stream *dev_stream,
94 const struct cras_audio_area *area,
95 unsigned int area_offset,
96 float software_gain_scaler);
97
98 /* Returns the number of iodevs this stream has attached to. */
99 int dev_stream_attached_devs(const struct dev_stream *dev_stream);
100
101 /* Updates the number of queued frames in dev_stream. */
102 void dev_stream_update_frames(const struct dev_stream *dev_stream);
103
104 /*
105 * Returns the number of playback frames queued in shared memory. This is a
106 * post-format-conversion number. If the stream is 24k with 10 frames queued
107 * and the device is playing at 48k, 20 will be returned.
108 */
109 int dev_stream_playback_frames(const struct dev_stream *dev_stream);
110
111 /*
112 * Returns the number of frames free to be written to in a capture stream. This
113 * number is also post format conversion, similar to playback_frames above.
114 */
115 unsigned int dev_stream_capture_avail(const struct dev_stream *dev_stream);
116
117 /*
118 * Returns the callback threshold, if necesary converted from a stream frame
119 * count to a device frame count.
120 */
121 unsigned int dev_stream_cb_threshold(const struct dev_stream *dev_stream);
122
123 /*
124 * If enough samples have been captured, post them to the client.
125 * TODO(dgreid) - see if this function can be eliminated.
126 */
127 int dev_stream_capture_update_rstream(struct dev_stream *dev_stream);
128
129 /* Updates the read buffer pointers for the stream. */
130 int dev_stream_playback_update_rstream(struct dev_stream *dev_stream);
131
132 /* Fill ts with the time the playback sample will be played. */
133 void cras_set_playback_timestamp(size_t frame_rate,
134 size_t frames,
135 struct cras_timespec *ts);
136
137 /* Fill ts with the time the capture sample was recorded. */
138 void cras_set_capture_timestamp(size_t frame_rate,
139 size_t frames,
140 struct cras_timespec *ts);
141
142 /* Fill shm ts with the time the playback sample will be played or the capture
143 * sample was captured depending on the direction of the stream.
144 * Args:
145 * delay_frames - The delay reproted by the device, in frames at the device's
146 * sample rate.
147 */
148 void dev_stream_set_delay(const struct dev_stream *dev_stream,
149 unsigned int delay_frames);
150
151 /* Returns if it's okay to request playback samples for this stream. */
152 int dev_stream_can_fetch(struct dev_stream *dev_stream);
153
154 /* Ask the client for cb_threshold samples of audio to play. */
155 int dev_stream_request_playback_samples(struct dev_stream *dev_stream,
156 const struct timespec *now);
157
158 /*
159 * Gets the wake up time for a dev_stream.
160 * For an input stream, it considers both needed samples and proper time
161 * interval between each callbacks.
162 * Args:
163 * dev_stream[in]: The dev_stream to check wake up time.
164 * curr_level[in]: The current level of device.
165 * level_tstamp[in]: The time stamp when getting current level of device.
166 * cap_limit[in]: The number of frames that can be captured across all
167 * streams.
168 * is_cap_limit_stream[in]: 1 if this stream is causing cap_limit.
169 * wake_time_out[out]: A timespec for wake up time.
170 * Returns:
171 * 0 on success; negative error code on failure.
172 * A positive value if there is no need to set wake up time for this stream.
173 */
174 int dev_stream_wake_time(struct dev_stream *dev_stream,
175 unsigned int curr_level,
176 struct timespec *level_tstamp,
177 unsigned int cap_limit,
178 int is_cap_limit_stream,
179 struct timespec *wake_time_out);
180
181 /*
182 * Returns a non-negative fd if the fd is expecting a message and should be
183 * added to the list of descriptors to poll.
184 */
185 int dev_stream_poll_stream_fd(const struct dev_stream *dev_stream);
186
187 static inline const struct timespec *
dev_stream_next_cb_ts(struct dev_stream * dev_stream)188 dev_stream_next_cb_ts(struct dev_stream *dev_stream)
189 {
190 if (dev_stream->stream->flags & USE_DEV_TIMING)
191 return NULL;
192
193 return &dev_stream->stream->next_cb_ts;
194 }
195
196 static inline const struct timespec *
dev_stream_sleep_interval_ts(struct dev_stream * dev_stream)197 dev_stream_sleep_interval_ts(struct dev_stream *dev_stream)
198 {
199 return &dev_stream->stream->sleep_interval_ts;
200 }
201
202 int dev_stream_is_pending_reply(const struct dev_stream *dev_stream);
203
204 /*
205 * Reads any pending audio message from the socket.
206 */
207 int dev_stream_flush_old_audio_messages(struct dev_stream *dev_stream);
208
209 #endif /* DEV_STREAM_H_ */
210