| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| |
| #ifndef ANDROID_AUDIO_HAL_INTERFACE_H |
| #define ANDROID_AUDIO_HAL_INTERFACE_H |
| |
| #include <stdint.h> |
| #include <strings.h> |
| #include <sys/cdefs.h> |
| #include <sys/types.h> |
| |
| #include <cutils/bitops.h> |
| |
| #include <hardware/hardware.h> |
| #include <system/audio.h> |
| #include <hardware/audio_effect.h> |
| |
| __BEGIN_DECLS |
| |
| /** |
| * The id of this module |
| */ |
| #define AUDIO_HARDWARE_MODULE_ID "audio" |
| |
| /** |
| * Name of the audio devices to open |
| */ |
| #define AUDIO_HARDWARE_INTERFACE "audio_hw_if" |
| |
| /**************************************/ |
| |
| /** |
| * standard audio parameters that the HAL may need to handle |
| */ |
| |
| /** |
| * audio device parameters |
| */ |
| |
| /* BT SCO Noise Reduction + Echo Cancellation parameters */ |
| #define AUDIO_PARAMETER_KEY_BT_NREC "bt_headset_nrec" |
| #define AUDIO_PARAMETER_VALUE_ON "on" |
| #define AUDIO_PARAMETER_VALUE_OFF "off" |
| |
| /* TTY mode selection */ |
| #define AUDIO_PARAMETER_KEY_TTY_MODE "tty_mode" |
| #define AUDIO_PARAMETER_VALUE_TTY_OFF "tty_off" |
| #define AUDIO_PARAMETER_VALUE_TTY_VCO "tty_vco" |
| #define AUDIO_PARAMETER_VALUE_TTY_HCO "tty_hco" |
| #define AUDIO_PARAMETER_VALUE_TTY_FULL "tty_full" |
| |
| /** |
| * audio stream parameters |
| */ |
| |
| #define AUDIO_PARAMETER_STREAM_ROUTING "routing" |
| #define AUDIO_PARAMETER_STREAM_FORMAT "format" |
| #define AUDIO_PARAMETER_STREAM_CHANNELS "channels" |
| #define AUDIO_PARAMETER_STREAM_FRAME_COUNT "frame_count" |
| #define AUDIO_PARAMETER_STREAM_INPUT_SOURCE "input_source" |
| |
| /**************************************/ |
| |
| /* common audio stream parameters and operations */ |
| struct audio_stream { |
| |
| /** |
| * sampling rate is in Hz - eg. 44100 |
| */ |
| uint32_t (*get_sample_rate)(const struct audio_stream *stream); |
| |
| /* currently unused - use set_parameters with key |
| * AUDIO_PARAMETER_STREAM_SAMPLING_RATE |
| */ |
| int (*set_sample_rate)(struct audio_stream *stream, uint32_t rate); |
| |
| /** |
| * size of output buffer in bytes - eg. 4800 |
| */ |
| size_t (*get_buffer_size)(const struct audio_stream *stream); |
| |
| /** |
| * the channel mask - |
| * e.g. AUDIO_CHANNEL_OUT_STEREO or AUDIO_CHANNEL_IN_STEREO |
| */ |
| uint32_t (*get_channels)(const struct audio_stream *stream); |
| |
| /** |
| * audio format - eg. AUDIO_FORMAT_PCM_16_BIT |
| */ |
| int (*get_format)(const struct audio_stream *stream); |
| |
| /* currently unused - use set_parameters with key |
| * AUDIO_PARAMETER_STREAM_FORMAT |
| */ |
| int (*set_format)(struct audio_stream *stream, int format); |
| |
| /** |
| * Put the audio hardware input/output into standby mode. |
| * Returns 0 on success and <0 on failure. |
| */ |
| int (*standby)(struct audio_stream *stream); |
| |
| /** dump the state of the audio input/output device */ |
| int (*dump)(const struct audio_stream *stream, int fd); |
| |
| audio_devices_t (*get_device)(const struct audio_stream *stream); |
| int (*set_device)(struct audio_stream *stream, audio_devices_t device); |
| |
| /** |
| * set/get audio stream parameters. The function accepts a list of |
| * parameter key value pairs in the form: key1=value1;key2=value2;... |
| * |
| * Some keys are reserved for standard parameters (See AudioParameter class) |
| * |
| * If the implementation does not accept a parameter change while |
| * the output is active but the parameter is acceptable otherwise, it must |
| * return -ENOSYS. |
| * |
| * The audio flinger will put the stream in standby and then change the |
| * parameter value. |
| */ |
| int (*set_parameters)(struct audio_stream *stream, const char *kv_pairs); |
| |
| /* |
| * Returns a pointer to a heap allocated string. The caller is responsible |
| * for freeing the memory for it. |
| */ |
| char * (*get_parameters)(const struct audio_stream *stream, |
| const char *keys); |
| int (*add_audio_effect)(const struct audio_stream *stream, |
| effect_handle_t effect); |
| int (*remove_audio_effect)(const struct audio_stream *stream, |
| effect_handle_t effect); |
| }; |
| typedef struct audio_stream audio_stream_t; |
| |
| /** |
| * audio_stream_out is the abstraction interface for the audio output hardware. |
| * |
| * It provides information about various properties of the audio output |
| * hardware driver. |
| */ |
| |
| struct audio_stream_out { |
| struct audio_stream common; |
| |
| /** |
| * return the audio hardware driver latency in milli seconds. |
| */ |
| uint32_t (*get_latency)(const struct audio_stream_out *stream); |
| |
| /** |
| * Use this method in situations where audio mixing is done in the |
| * hardware. This method serves as a direct interface with hardware, |
| * allowing you to directly set the volume as apposed to via the framework. |
| * This method might produce multiple PCM outputs or hardware accelerated |
| * codecs, such as MP3 or AAC. |
| */ |
| int (*set_volume)(struct audio_stream_out *stream, float left, float right); |
| |
| /** |
| * write audio buffer to driver. Returns number of bytes written |
| */ |
| ssize_t (*write)(struct audio_stream_out *stream, const void* buffer, |
| size_t bytes); |
| |
| /* return the number of audio frames written by the audio dsp to DAC since |
| * the output has exited standby |
| */ |
| int (*get_render_position)(const struct audio_stream_out *stream, |
| uint32_t *dsp_frames); |
| }; |
| typedef struct audio_stream_out audio_stream_out_t; |
| |
| struct audio_stream_in { |
| struct audio_stream common; |
| |
| /** set the input gain for the audio driver. This method is for |
| * for future use */ |
| int (*set_gain)(struct audio_stream_in *stream, float gain); |
| |
| /** read audio buffer in from audio driver */ |
| ssize_t (*read)(struct audio_stream_in *stream, void* buffer, |
| size_t bytes); |
| |
| /** |
| * Return the amount of input frames lost in the audio driver since the |
| * last call of this function. |
| * Audio driver is expected to reset the value to 0 and restart counting |
| * upon returning the current value by this function call. |
| * Such loss typically occurs when the user space process is blocked |
| * longer than the capacity of audio driver buffers. |
| * |
| * Unit: the number of input audio frames |
| */ |
| uint32_t (*get_input_frames_lost)(struct audio_stream_in *stream); |
| }; |
| typedef struct audio_stream_in audio_stream_in_t; |
| |
| /** |
| * return the frame size (number of bytes per sample). |
| */ |
| static inline uint32_t audio_stream_frame_size(struct audio_stream *s) |
| { |
| int chan_samp_sz; |
| |
| switch (s->get_format(s)) { |
| case AUDIO_FORMAT_PCM_16_BIT: |
| chan_samp_sz = sizeof(int16_t); |
| break; |
| case AUDIO_FORMAT_PCM_8_BIT: |
| default: |
| chan_samp_sz = sizeof(int8_t); |
| break; |
| } |
| |
| return popcount(s->get_channels(s)) * chan_samp_sz; |
| } |
| |
| |
| /**********************************************************************/ |
| |
| /** |
| * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM |
| * and the fields of this data structure must begin with hw_module_t |
| * followed by module specific information. |
| */ |
| struct audio_module { |
| struct hw_module_t common; |
| }; |
| |
| struct audio_hw_device { |
| struct hw_device_t common; |
| |
| /** |
| * used by audio flinger to enumerate what devices are supported by |
| * each audio_hw_device implementation. |
| * |
| * Return value is a bitmask of 1 or more values of audio_devices_t |
| */ |
| uint32_t (*get_supported_devices)(const struct audio_hw_device *dev); |
| |
| /** |
| * check to see if the audio hardware interface has been initialized. |
| * returns 0 on success, -ENODEV on failure. |
| */ |
| int (*init_check)(const struct audio_hw_device *dev); |
| |
| /** set the audio volume of a voice call. Range is between 0.0 and 1.0 */ |
| int (*set_voice_volume)(struct audio_hw_device *dev, float volume); |
| |
| /** |
| * set the audio volume for all audio activities other than voice call. |
| * Range between 0.0 and 1.0. If any value other than 0 is returned, |
| * the software mixer will emulate this capability. |
| */ |
| int (*set_master_volume)(struct audio_hw_device *dev, float volume); |
| |
| /** |
| * setMode is called when the audio mode changes. AUDIO_MODE_NORMAL mode |
| * is for standard audio playback, AUDIO_MODE_RINGTONE when a ringtone is |
| * playing, and AUDIO_MODE_IN_CALL when a call is in progress. |
| */ |
| int (*set_mode)(struct audio_hw_device *dev, int mode); |
| |
| /* mic mute */ |
| int (*set_mic_mute)(struct audio_hw_device *dev, bool state); |
| int (*get_mic_mute)(const struct audio_hw_device *dev, bool *state); |
| |
| /* set/get global audio parameters */ |
| int (*set_parameters)(struct audio_hw_device *dev, const char *kv_pairs); |
| |
| /* |
| * Returns a pointer to a heap allocated string. The caller is responsible |
| * for freeing the memory for it. |
| */ |
| char * (*get_parameters)(const struct audio_hw_device *dev, |
| const char *keys); |
| |
| /* Returns audio input buffer size according to parameters passed or |
| * 0 if one of the parameters is not supported |
| */ |
| size_t (*get_input_buffer_size)(const struct audio_hw_device *dev, |
| uint32_t sample_rate, int format, |
| int channel_count); |
| |
| /** This method creates and opens the audio hardware output stream */ |
| int (*open_output_stream)(struct audio_hw_device *dev, uint32_t devices, |
| int *format, uint32_t *channels, |
| uint32_t *sample_rate, |
| struct audio_stream_out **out); |
| |
| void (*close_output_stream)(struct audio_hw_device *dev, |
| struct audio_stream_out* out); |
| |
| /** This method creates and opens the audio hardware input stream */ |
| int (*open_input_stream)(struct audio_hw_device *dev, uint32_t devices, |
| int *format, uint32_t *channels, |
| uint32_t *sample_rate, |
| audio_in_acoustics_t acoustics, |
| struct audio_stream_in **stream_in); |
| |
| void (*close_input_stream)(struct audio_hw_device *dev, |
| struct audio_stream_in *in); |
| |
| /** This method dumps the state of the audio hardware */ |
| int (*dump)(const struct audio_hw_device *dev, int fd); |
| }; |
| typedef struct audio_hw_device audio_hw_device_t; |
| |
| /** convenience API for opening and closing a supported device */ |
| |
| static inline int audio_hw_device_open(const struct hw_module_t* module, |
| struct audio_hw_device** device) |
| { |
| return module->methods->open(module, AUDIO_HARDWARE_INTERFACE, |
| (struct hw_device_t**)device); |
| } |
| |
| static inline int audio_hw_device_close(struct audio_hw_device* device) |
| { |
| return device->common.close(&device->common); |
| } |
| |
| |
| __END_DECLS |
| |
| #endif // ANDROID_AUDIO_INTERFACE_H |