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 }; 39 40 typedef void (*cras_ramp_cb)(void *arg); 41 42 /* Creates a ramp. */ 43 struct cras_ramp* cras_ramp_create(); 44 45 /* Destroys a ramp. */ 46 void cras_ramp_destroy(struct cras_ramp* ramp); 47 48 /* Starts ramping up from 0 to 1 or from 1 to 0 for duration_frames frames. 49 * Args: 50 * ramp[in]: The ramp struct to start. 51 * is_up[in]: 1 to ramp up and 0 to ramp down. 52 * duration_frames[in]: Ramp duration in frames. 53 * cb[in]: The callback function to call after ramping is done. User can set 54 * cb to turn off speaker/headphone switch after ramping down 55 * is done. 56 * cb_data[in]: The data passed to callback function. 57 * Returns: 58 * 0 on success; negative error code on failure. 59 */ 60 int cras_ramp_start(struct cras_ramp *ramp, int is_up, int duration_frames, 61 cras_ramp_cb cb, void *cb_data); 62 63 /* Resets ramp and cancels current ramping. */ 64 int cras_ramp_reset(struct cras_ramp *ramp); 65 66 /* Gets current ramp action. */ 67 struct cras_ramp_action cras_ramp_get_current_action( 68 const struct cras_ramp *ramp); 69 70 /* Updates number of samples that went through ramping. */ 71 int cras_ramp_update_ramped_frames( 72 struct cras_ramp *ramp, int num_frames); 73 74 #endif /* CRAS_RAMP_H_ */ 75
