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 * is_running - For input stream, it should be set to true after it is added
33 * into device. For output stream, it should be set to true
34 * just before its first fetch to avoid affecting other existing
35 * streams.
36 */
37 struct dev_stream {
38 unsigned int dev_id;
39 struct cras_rstream *stream;
40 struct cras_fmt_conv *conv;
41 struct byte_buffer *conv_buffer;
42 struct cras_audio_area *conv_area;
43 unsigned int conv_buffer_size_frames;
44 size_t dev_rate;
45 struct dev_stream *prev, *next;
46 int is_running;
47 };
48
49 /*
50 * Creates a dev_stream.
51 *
52 * Args:
53 * stream - The associated rstream.
54 * dev_id - Index of the device.
55 * dev_fmt - The format of the device.
56 * dev_ptr - A pointer to the device
57 * cb_ts - A pointer to the initial callback time.
58 * sleep_interval_ts - A pointer to the initial sleep interval.
59 * Set to null to calculate the value from device rate and block size.
60 * Note that we need this argument so that output device sleep interval
61 * can use input device sleep interval in the beginning to have perfect
62 * alignment in WebRTC use case.
63 * Returns the pointer to the created dev_stream.
64 */
65 struct dev_stream *dev_stream_create(struct cras_rstream *stream,
66 unsigned int dev_id,
67 const struct cras_audio_format *dev_fmt,
68 void *dev_ptr, struct timespec *cb_ts,
69 const struct timespec *sleep_interval_ts);
70 void dev_stream_destroy(struct dev_stream *dev_stream);
71
72 /*
73 * Update the estimated sample rate of the device. For multiple active
74 * devices case, the linear resampler will be configured by the estimated
75 * rate ration of the main device and the current active device the
76 * rstream attaches to.
77 *
78 * Args:
79 * dev_stream - The structure holding the stream.
80 * dev_rate - The sample rate device is using.
81 * dev_rate_ratio - The ratio of estimated rate and used rate.
82 * main_rate_ratio - The ratio of estimated rate and used rate of
83 * main device.
84 * coarse_rate_adjust - The flag to indicate the direction device
85 * sample rate should adjust to.
86 */
87 void dev_stream_set_dev_rate(struct dev_stream *dev_stream,
88 unsigned int dev_rate, double dev_rate_ratio,
89 double main_rate_ratio, int coarse_rate_adjust);
90
91 /*
92 * Renders count frames from shm into dst. Updates count if anything is
93 * written. If it's muted and the only stream zero memory.
94 * Args:
95 * dev_stream - The struct holding the stream to mix.
96 * format - The format of the audio device.
97 * dst - The destination buffer for mixing.
98 * num_to_write - The number of frames written.
99 */
100 int dev_stream_mix(struct dev_stream *dev_stream,
101 const struct cras_audio_format *fmt, uint8_t *dst,
102 unsigned int num_to_write);
103
104 /*
105 * Reads froms from the source into the dev_stream.
106 * Args:
107 * dev_stream - The struct holding the stream to mix to.
108 * area - The area to copy audio from.
109 * area_offset - The offset at which to start reading from area.
110 * software_gain_scaler - The software gain scaler.
111 */
112 unsigned int dev_stream_capture(struct dev_stream *dev_stream,
113 const struct cras_audio_area *area,
114 unsigned int area_offset,
115 float software_gain_scaler);
116
117 /* Returns the number of iodevs this stream has attached to. */
118 int dev_stream_attached_devs(const struct dev_stream *dev_stream);
119
120 /* Updates the number of queued frames in dev_stream. */
121 void dev_stream_update_frames(const struct dev_stream *dev_stream);
122
123 /*
124 * Returns the number of playback frames queued in shared memory. This is a
125 * post-format-conversion number. If the stream is 24k with 10 frames queued
126 * and the device is playing at 48k, 20 will be returned.
127 */
128 int dev_stream_playback_frames(const struct dev_stream *dev_stream);
129
130 /*
131 * Returns the number of frames free to be written to in a capture stream. This
132 * number is also post format conversion, similar to playback_frames above.
133 */
134 unsigned int dev_stream_capture_avail(const struct dev_stream *dev_stream);
135
136 /*
137 * Returns the callback threshold, if necesary converted from a stream frame
138 * count to a device frame count.
139 */
140 unsigned int dev_stream_cb_threshold(const struct dev_stream *dev_stream);
141
142 /* Update next callback time for the stream. */
143 void dev_stream_update_next_wake_time(struct dev_stream *dev_stream);
144
145 /*
146 * If enough samples have been captured, post them to the client.
147 * TODO(dgreid) - see if this function can be eliminated.
148 */
149 int dev_stream_capture_update_rstream(struct dev_stream *dev_stream);
150
151 /* Updates the read buffer pointers for the stream. */
152 int dev_stream_playback_update_rstream(struct dev_stream *dev_stream);
153
154 /* Fill ts with the time the playback sample will be played. */
155 void cras_set_playback_timestamp(size_t frame_rate, size_t frames,
156 struct cras_timespec *ts);
157
158 /* Fill ts with the time the capture sample was recorded. */
159 void cras_set_capture_timestamp(size_t frame_rate, size_t frames,
160 struct cras_timespec *ts);
161
162 /* Fill shm ts with the time the playback sample will be played or the capture
163 * sample was captured depending on the direction of the stream.
164 * Args:
165 * delay_frames - The delay reproted by the device, in frames at the device's
166 * sample rate.
167 */
168 void dev_stream_set_delay(const struct dev_stream *dev_stream,
169 unsigned int delay_frames);
170
171 /* Ask the client for cb_threshold samples of audio to play. */
172 int dev_stream_request_playback_samples(struct dev_stream *dev_stream,
173 const struct timespec *now);
174
175 /*
176 * Gets the wake up time for a dev_stream.
177 * For an input stream, it considers both needed samples and proper time
178 * interval between each callbacks.
179 * Args:
180 * dev_stream[in]: The dev_stream to check wake up time.
181 * curr_level[in]: The current level of device.
182 * level_tstamp[in]: The time stamp when getting current level of device.
183 * cap_limit[in]: The number of frames that can be captured across all
184 * streams.
185 * is_cap_limit_stream[in]: 1 if this stream is causing cap_limit.
186 * wake_time_out[out]: A timespec for wake up time.
187 * Returns:
188 * 0 on success; negative error code on failure.
189 * A positive value if there is no need to set wake up time for this stream.
190 */
191 int dev_stream_wake_time(struct dev_stream *dev_stream, unsigned int curr_level,
192 struct timespec *level_tstamp, unsigned int cap_limit,
193 int is_cap_limit_stream,
194 struct timespec *wake_time_out);
195
196 /*
197 * Returns a non-negative fd if the fd is expecting a message and should be
198 * added to the list of descriptors to poll.
199 */
200 int dev_stream_poll_stream_fd(const struct dev_stream *dev_stream);
201
dev_stream_is_running(struct dev_stream * dev_stream)202 static inline int dev_stream_is_running(struct dev_stream *dev_stream)
203 {
204 return dev_stream->is_running;
205 }
206
dev_stream_set_running(struct dev_stream * dev_stream)207 static inline void dev_stream_set_running(struct dev_stream *dev_stream)
208 {
209 dev_stream->is_running = 1;
210 }
211
212 static inline const struct timespec *
dev_stream_next_cb_ts(const struct dev_stream * dev_stream)213 dev_stream_next_cb_ts(const struct dev_stream *dev_stream)
214 {
215 if (dev_stream->stream->flags & USE_DEV_TIMING)
216 return NULL;
217
218 return &dev_stream->stream->next_cb_ts;
219 }
220
221 static inline const struct timespec *
dev_stream_sleep_interval_ts(struct dev_stream * dev_stream)222 dev_stream_sleep_interval_ts(struct dev_stream *dev_stream)
223 {
224 return &dev_stream->stream->sleep_interval_ts;
225 }
226
227 int dev_stream_is_pending_reply(const struct dev_stream *dev_stream);
228
229 /*
230 * Reads any pending audio message from the socket.
231 */
232 int dev_stream_flush_old_audio_messages(struct dev_stream *dev_stream);
233
234 #endif /* DEV_STREAM_H_ */
235