• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* Copyright 2016 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 
6 #ifndef CRAS_RAMP_H_
7 #define CRAS_RAMP_H_
8 
9 #include "cras_iodev.h"
10 
11 struct cras_ramp;
12 
13 /*
14  * Infomation telling user how to do ramping.
15  * action CRAS_RAMP_ACTION_NONE: No scale should be applied.
16  * action CRAS_RAMP_ACTION_PARTIAL: scale sample by sample starting from scaler
17  *                                  and increase increment for each sample.
18  * action CRAS_RAMP_ACTION_INVALID: There is an error in cras_ramp.
19  */
20 enum CRAS_RAMP_ACTION_TYPE {
21 	CRAS_RAMP_ACTION_NONE,
22 	CRAS_RAMP_ACTION_PARTIAL,
23 	CRAS_RAMP_ACTION_INVALID,
24 };
25 
26 /*
27  * Struct to hold current ramping action for user.
28  * Members:
29  *   type: See CRAS_RAMP_ACTION_TYPE.
30  *   scaler: The initial scaler to be applied.
31  *   increment: The scaler increment that should be added to scaler for every
32  *              frame.
33  */
34 struct cras_ramp_action {
35 	enum CRAS_RAMP_ACTION_TYPE type;
36 	float scaler;
37 	float increment;
38 	float target;
39 };
40 
41 typedef void (*cras_ramp_cb)(void *arg);
42 
43 /* Creates a ramp. */
44 struct cras_ramp *cras_ramp_create();
45 
46 /* Destroys a ramp. */
47 void cras_ramp_destroy(struct cras_ramp *ramp);
48 
49 /* Ramps the scaler between from and to for duration_frames frames.
50  * Args:
51  *   ramp[in]: The ramp struct to start.
52  *   mute_ramp[in]: Is this ramp a mute->unmute or unmute->mute ramp.
53  *   from[in]: The scaler value to ramp from.
54  *   to[in]: The scaler value to ramp to.
55  *   duration_frames[in]: Ramp duration in frames.
56  *   cb[in]: The callback function to call after ramping is done. User can set
57  *           cb to turn off speaker/headphone switch after ramping down
58  *           is done.
59  *   cb_data[in]: The data passed to callback function.
60  * Returns:
61  *   0 on success; negative error code on failure.
62  */
63 int cras_ramp_start(struct cras_ramp *ramp, int mute_ramp, float from, float to,
64 		    int duration_frames, cras_ramp_cb cb, void *cb_data);
65 
66 /* Convenience wrappers for cras_ramp_start */
cras_mute_ramp_start(struct cras_ramp * ramp,float from,float to,int duration_frames,cras_ramp_cb cb,void * cb_data)67 static inline int cras_mute_ramp_start(struct cras_ramp *ramp, float from,
68 				       float to, int duration_frames,
69 				       cras_ramp_cb cb, void *cb_data)
70 {
71 	return cras_ramp_start(ramp, 1, from, to, duration_frames, cb, cb_data);
72 }
73 
cras_volume_ramp_start(struct cras_ramp * ramp,float from,float to,int duration_frames,cras_ramp_cb cb,void * cb_data)74 static inline int cras_volume_ramp_start(struct cras_ramp *ramp, float from,
75 					 float to, int duration_frames,
76 					 cras_ramp_cb cb, void *cb_data)
77 {
78 	return cras_ramp_start(ramp, 0, from, to, duration_frames, cb, cb_data);
79 }
80 
81 /* Resets ramp and cancels current ramping. */
82 int cras_ramp_reset(struct cras_ramp *ramp);
83 
84 /* Gets current ramp action. */
85 struct cras_ramp_action
86 cras_ramp_get_current_action(const struct cras_ramp *ramp);
87 
88 /* Updates number of samples that went through ramping. */
89 int cras_ramp_update_ramped_frames(struct cras_ramp *ramp, int num_frames);
90 
91 #endif /* CRAS_RAMP_H_ */
92