include/nuttx/audio/audio.h (395 lines of code) (raw):

/**************************************************************************** * include/nuttx/audio/audio.h * * SPDX-License-Identifier: Apache-2.0 * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you 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 __INCLUDE_NUTTX_AUDIO_AUDIO_H #define __INCLUDE_NUTTX_AUDIO_AUDIO_H /* For the purposes of this driver, an Audio device is any device that * generates, records, mixes, or otherwise modifies audio data in any format, * such as PCM, MP3, AAC, etc. * * The Audio driver is split into two parts: * * 1) An "upper half", generic driver that provides the common Audio * interface to application level code, and * 2) A "lower half", platform-specific driver that implements the * low-level controls to configure and communicate with the audio * device(s). */ /**************************************************************************** * Included Files ****************************************************************************/ #include <nuttx/config.h> #include <nuttx/compiler.h> #include <nuttx/fs/ioctl.h> #include <nuttx/mutex.h> #include <nuttx/spi/spi.h> #include <nuttx/queue.h> #ifdef CONFIG_AUDIO /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Configuration ************************************************************/ /* CONFIG_AUDIO - Enables Audio driver support * CONFIG_DEBUG_AUDIO - If enabled (with CONFIG_DEBUG_FEATURES and, * optionally, CONFIG_DEBUG_INFO), this will generate output that can * be used to debug Audio drivers. */ /* IOCTL Commands ***********************************************************/ /* The Audio module uses a standard character driver framework. However, a * lot of the Audio driver functionality is configured via a device control * interface, such as sampling rate, volume, data format, etc. * The Audio ioctl commands are listed below: * * AUDIOIOC_GETCAPS - Get the Audio Device Capabilities * * ioctl argument: Pointer to the audio_caps_s structure to receive the * capabilities info. The "len" and "type" fields should * be filled in prior to calling this ioctl. To get * overall capabilities, specify the type as * AUDIO_TYPE_QUERY, otherwise specify any type that was * reported by the device during the QUERY. * * AUDIOIOC_CONFIGURE - Configure device for the specified mode * * ioctl argument: Pointer to the audio_caps_s structure which identifies * the capabilities to configure for. * * AUDIOIOC_SHUTDOWN - Shutdown the device. * * ioctl argument: None * * AUDIOIOC_START - Start Audio streaming * * ioctl argument: None * * AUDIOIOC_STOP - Stop Audio streaming * * ioctl argument: None */ #define AUDIOIOC_GETCAPS _AUDIOIOC(1) #define AUDIOIOC_RESERVE _AUDIOIOC(2) #define AUDIOIOC_RELEASE _AUDIOIOC(3) #define AUDIOIOC_CONFIGURE _AUDIOIOC(4) #define AUDIOIOC_SHUTDOWN _AUDIOIOC(5) #define AUDIOIOC_START _AUDIOIOC(6) #define AUDIOIOC_STOP _AUDIOIOC(7) #define AUDIOIOC_PAUSE _AUDIOIOC(8) #define AUDIOIOC_RESUME _AUDIOIOC(9) #define AUDIOIOC_GETBUFFERINFO _AUDIOIOC(10) #define AUDIOIOC_ALLOCBUFFER _AUDIOIOC(11) #define AUDIOIOC_FREEBUFFER _AUDIOIOC(12) #define AUDIOIOC_ENQUEUEBUFFER _AUDIOIOC(13) #define AUDIOIOC_REGISTERMQ _AUDIOIOC(14) #define AUDIOIOC_UNREGISTERMQ _AUDIOIOC(15) #define AUDIOIOC_HWRESET _AUDIOIOC(16) #define AUDIOIOC_SETBUFFERINFO _AUDIOIOC(17) #define AUDIOIOC_SETPARAMTER _AUDIOIOC(18) #define AUDIOIOC_GETLATENCY _AUDIOIOC(19) #define AUDIOIOC_FLUSH _AUDIOIOC(20) #define AUDIOIOC_GETPOSITION _AUDIOIOC(21) /* Audio Device Types *******************************************************/ /* The NuttX audio interface support different types of audio devices for * input, output, synthesis, and manipulation of audio data. A given driver/ * device could support a combination of these device type. The following * is a list of bit-field definitions for defining the device type. */ #define AUDIO_TYPE_QUERY 0x00 #define AUDIO_TYPE_INPUT 0x01 #define AUDIO_TYPE_OUTPUT 0x02 #define AUDIO_TYPE_MIXER 0x04 #define AUDIO_TYPE_SELECTOR 0x08 #define AUDIO_TYPE_FEATURE 0x10 #define AUDIO_TYPE_EFFECT 0x20 #define AUDIO_TYPE_PROCESSING 0x40 #define AUDIO_TYPE_EXTENSION 0x80 /* Audio Format Types *******************************************************/ /* The following defines the audio data format types in NuttX. During a * format query, these will be converted to bit positions within the * ac_format field, meaning we currently only support up to 16 formats. To * support more than that, we will use the FMT_OTHER entry, and the * interfacing software can perform a second query to get the other formats. */ #define AUDIO_FMT_UNDEF 0x00 #define AUDIO_FMT_OTHER 0x01 #define AUDIO_FMT_MPEG 0x02 #define AUDIO_FMT_AC3 0x03 #define AUDIO_FMT_WMA 0x04 #define AUDIO_FMT_DTS 0x05 #define AUDIO_FMT_PCM 0x06 #define AUDIO_FMT_WAV 0x07 #define AUDIO_FMT_MP3 0x08 #define AUDIO_FMT_MIDI 0x09 #define AUDIO_FMT_OGG_VORBIS 0x0a #define AUDIO_FMT_FLAC 0x0b #define AUDIO_FMT_SBC 0x0c #define AUDIO_FMT_AAC 0x0d #define AUDIO_FMT_MSBC 0x0e #define AUDIO_FMT_CVSD 0x0f #define AUDIO_FMT_AMR 0x10 #define AUDIO_FMT_OPUS 0x11 /* Audio Sub-Format Types ***************************************************/ #define AUDIO_SUBFMT_END 0x00 #define AUDIO_SUBFMT_PCM_MP1 0x01 #define AUDIO_SUBFMT_PCM_MP2 0x02 #define AUDIO_SUBFMT_PCM_MP3 0x03 #define AUDIO_SUBFMT_PCM_MU_LAW 0x04 #define AUDIO_SUBFMT_PCM_A_LAW 0x05 #define AUDIO_SUBFMT_PCM_U8 0x06 #define AUDIO_SUBFMT_PCM_S8 0x07 #define AUDIO_SUBFMT_PCM_U16_LE 0x08 #define AUDIO_SUBFMT_PCM_S16_BE 0x09 #define AUDIO_SUBFMT_PCM_S16_LE 0x0a #define AUDIO_SUBFMT_PCM_U16_BE 0x0b #define AUDIO_SUBFMT_PCM_U32_LE 0x0c #define AUDIO_SUBFMT_PCM_U32_BE 0x0d #define AUDIO_SUBFMT_PCM_S32_LE 0x0e #define AUDIO_SUBFMT_PCM_S32_BE 0x0f #define AUDIO_SUBFMT_MIDI_0 0x10 #define AUDIO_SUBFMT_MIDI_1 0x11 #define AUDIO_SUBFMT_MIDI_2 0x12 #define AUDIO_SUBFMT_AMRNB 0x13 #define AUDIO_SUBFMT_AMRWB 0x14 /* Audio Hardware-Format Types **********************************************/ #define AUDIO_HWFMT_I2S (1 << 0) #define AUDIO_HWFMT_RIGHT_J (2 << 0) #define AUDIO_HWFMT_LEFT_J (3 << 0) #define AUDIO_HWFMT_DSP_A (4 << 0) #define AUDIO_HWFMT_DSP_B (5 << 0) #define AUDIO_HWFMT_AC97 (6 << 0) #define AUDIO_HWFMT_PDM (7 << 0) #define AUDIO_HWFMT_NB_NF (0 << 8) #define AUDIO_HWFMT_NB_IF (2 << 8) #define AUDIO_HWFMT_IB_NF (3 << 8) #define AUDIO_HWFMT_IB_IF (4 << 8) #define AUDIO_HWFMT_CBM_CFM (1 << 12) #define AUDIO_HWFMT_CBS_CFM (2 << 12) #define AUDIO_HWFMT_CBM_CFS (3 << 12) #define AUDIO_HWFMT_CBS_CFS (4 << 12) #define AUDIO_HWFMT_FORMAT_MASK 0x000f #define AUDIO_HWFMT_CLOCK_MASK 0x00f0 #define AUDIO_HWFMT_INV_MASK 0x0f00 #define AUDIO_HWFMT_MASTER_MASK 0xf000 /* Supported Sampling Rates *************************************************/ #define AUDIO_SAMP_RATE_8K 0x0001 #define AUDIO_SAMP_RATE_11K 0x0002 #define AUDIO_SAMP_RATE_12K 0x0004 #define AUDIO_SAMP_RATE_16K 0x0008 #define AUDIO_SAMP_RATE_22K 0x0010 #define AUDIO_SAMP_RATE_24K 0x0020 #define AUDIO_SAMP_RATE_32K 0x0040 #define AUDIO_SAMP_RATE_44K 0x0080 #define AUDIO_SAMP_RATE_48K 0x0100 #define AUDIO_SAMP_RATE_88K 0x0200 #define AUDIO_SAMP_RATE_96K 0x0400 #define AUDIO_SAMP_RATE_128K 0x0800 #define AUDIO_SAMP_RATE_160K 0x1000 #define AUDIO_SAMP_RATE_172K 0x2000 #define AUDIO_SAMP_RATE_192K 0x4000 #define AUDIO_SAMP_RATE_DEF_ALL (AUDIO_SAMP_RATE_8K | AUDIO_SAMP_RATE_11K | \ AUDIO_SAMP_RATE_12K | AUDIO_SAMP_RATE_16K | \ AUDIO_SAMP_RATE_22K | AUDIO_SAMP_RATE_24K | \ AUDIO_SAMP_RATE_32K | AUDIO_SAMP_RATE_44K | \ AUDIO_SAMP_RATE_48K | AUDIO_SAMP_RATE_88K | \ AUDIO_SAMP_RATE_96K | AUDIO_SAMP_RATE_128K | \ AUDIO_SAMP_RATE_160K | AUDIO_SAMP_RATE_172K | \ AUDIO_SAMP_RATE_192K) /* Audio Sub-sampling Ratios ***********************************************/ #define AUDIO_SUBSAMPLE_NONE 0 #define AUDIO_SUBSAMPLE_2X 2 #define AUDIO_SUBSAMPLE_4X 4 #define AUDIO_SUBSAMPLE_8X 8 #define AUDIO_SUBSAMPLE_16X 16 #define AUDIO_SUBSAMPLE_MIN AUDIO_SUBSAMPLE_2X #define AUDIO_SUBSAMPLE_MAX AUDIO_SUBSAMPLE_16X /* Supported Bit Rates ******************************************************/ #define AUDIO_BIT_RATE_22K 0x01 #define AUDIO_BIT_RATE_44K 0x02 #define AUDIO_BIT_RATE_48K 0x04 #define AUDIO_BIT_RATE_96K 0x08 #define AUDIO_BIT_RATE_128K 0x10 #define AUDIO_BIT_RATE_160K 0x20 #define AUDIO_BIT_RATE_172K 0x40 #define AUDIO_BIT_RATE_192K 0x80 /* Audio Volume Limits ******************************************************/ /* As nxplayer passes a value in the range (0..1000) to the ioctl, all audio * drivers that implement volume expect a value from 0 to 1000 from the ioctl */ #define AUDIO_VOLUME_MAX 1000 #define AUDIO_VOLUME_MIN 0 /* Audio Balance Limits *****************************************************/ /* As nxplayer passes a value in the range (0..1000) to the ioctl, all audio * drivers that implement balance expect a value from 0 to 1000 from the * ioctl */ #define AUDIO_BALANCE_RIGHT 1000 #define AUDIO_BALANCE_CENTER 500 #define AUDIO_BALANCE_LEFT 0 /* Supported Feature Units controls *****************************************/ #define AUDIO_FU_UNDEF 0x0000 #define AUDIO_FU_MUTE 0x0001 #define AUDIO_FU_VOLUME 0x0002 #define AUDIO_FU_BASS 0x0004 #define AUDIO_FU_MID 0x0008 #define AUDIO_FU_TREBLE 0x0010 #define AUDIO_FU_EQUALIZER 0x0020 #define AUDIO_FU_AGC 0x0040 #define AUDIO_FU_DELAY 0x0080 #define AUDIO_FU_BASS_BOOST 0x0100 #define AUDIO_FU_LOUDNESS 0x0200 #define AUDIO_FU_INP_GAIN 0x0400 #define AUDIO_FU_BALANCE 0x0800 #define AUDIO_FU_PHASE_INVERT 0x1000 #define AUDIO_FU_UNDERFLOW 0x2000 #define AUDIO_FU_OVERFLOW 0x4000 #define AUDIO_FU_LATENCY 0x8000 /* Processing Unit controls *************************************************/ #define AUDIO_PU_UNDEF 0x00 #define AUDIO_PU_UPDOWNMIX 0x01 #define AUDIO_PU_DOLBY_PROLOGIC 0x02 #define AUDIO_PU_STEREO_EXTENDER 0x03 #define AUDIO_PU_SUBSAMPLE_FORWARD 0x04 #define AUDIO_PU_SUBSAMPLE_REWIND 0x05 /* Stereo Extender PU Controls **********************************************/ #define AUDIO_STEXT_UNDEF 0x00 #define AUDIO_STEXT_ENABLE 0x01 #define AUDIO_STEXT_WIDTH 0x02 #define AUDIO_STEXT_UNDERFLOW 0x03 #define AUDIO_STEXT_OVERFLOW 0x04 #define AUDIO_STEXT_LATENCY 0x05 /* Extension Unit controls **************************************************/ #define AUDIO_EU_HW_FORMAT 0x0001 #define AUDIO_EU_LOAD_MODULE 0x0002 /* Audio Callback Reasons ***************************************************/ #define AUDIO_CALLBACK_UNDEF 0x00 #define AUDIO_CALLBACK_DEQUEUE 0x01 #define AUDIO_CALLBACK_IOERR 0x02 #define AUDIO_CALLBACK_COMPLETE 0x03 #define AUDIO_CALLBACK_MESSAGE 0x04 #define AUDIO_CALLBACK_UNDERRUN 0x05 /* Audio Pipeline Buffer (AP Buffer) flags **********************************/ #define AUDIO_ABP_ALIGNMENT 0x000f /* Mask to define buffer alignment */ #define AUDIO_ABP_CANDMA 0x0010 /* Set if the data is DMA'able */ #define AUDIO_ABP_STATIC 0x0020 /* Set if statically allocated */ #define AUDIO_ABP_ACTIVE 0x0040 /* Set if this buffer is still active. * A buffer could become inactive * if it is processed by an output * device or a processing device * that replaces it with an alternate * buffer as a result of some DSP * operation, etc. */ /* Standard Audio Message Queue message IDs */ #define AUDIO_MSG_NONE 0 #define AUDIO_MSG_DEQUEUE 1 #define AUDIO_MSG_START 2 #define AUDIO_MSG_STOP 3 #define AUDIO_MSG_PAUSE 4 #define AUDIO_MSG_RESUME 5 #define AUDIO_MSG_DATA_REQUEST 6 #define AUDIO_MSG_ENQUEUE 7 #define AUDIO_MSG_COMPLETE 8 #define AUDIO_MSG_WAKEUP 9 #define AUDIO_MSG_COMMAND 10 #define AUDIO_MSG_SLIENCE 11 #define AUDIO_MSG_UNDERRUN 12 #define AUDIO_MSG_IOERR 13 #define AUDIO_MSG_USER 64 /* Audio Pipeline Buffer flags */ #define AUDIO_APB_OUTPUT_ENQUEUED (1 << 0) #define AUDIO_APB_OUTPUT_PROCESS (1 << 1) #define AUDIO_APB_DEQUEUED (1 << 2) #define AUDIO_APB_FINAL (1 << 3) /* Last buffer in the stream */ /* Audio channels range wrapper macro */ #define AUDIO_CHANNELS_RANGE(min, max) ((uint8_t)(((min) << 4) | ((max) & 0xf))) /**************************************************************************** * Public Types ****************************************************************************/ /* Define the size of AP Buffer sample count base on CONFIG */ #ifdef CONFIG_AUDIO_LARGE_BUFFERS typedef uint32_t apb_samp_t; #else typedef uint16_t apb_samp_t; #endif /* This structure is used to describe the audio device capabilities */ struct audio_caps_s { uint8_t ac_len; /* Length of the structure */ uint8_t ac_type; /* Capabilities (device) type */ uint8_t ac_subtype; /* Capabilities sub-type, if needed */ uint8_t ac_channels; /* Number of channels (1, 2, 3, ... 15) upper 4 bits for minimum channels, * lower 4 bits for maximum channels */ uint8_t ac_chmap; /* Channel map, each ch for each bit, * zero means don't care */ uint8_t reserved; /* Reserved for future use */ /* Audio data format(s) for this device */ union { uint8_t b[2]; uint16_t hw; } ac_format; /* Specific controls for AUDIO_DEVICE_QUERY * this field reports the device type supported * by this lower-half driver. */ union { uint8_t b[4]; uint16_t hw[2]; uint32_t w; #ifdef CONFIG_HAVE_LONG_LONG uint64_t qw; #endif } ac_controls; }; struct audio_caps_desc_s { #ifdef CONFIG_AUDIO_MULTI_SESSION FAR void *session; /* Associated session */ #endif struct audio_caps_s caps; /* The capabilities struct */ }; /* This structure describes the characteristics of the Audio samples */ struct audio_info_s { uint32_t samplerate; /* Sample Rate of the audio data */ uint8_t channels; /* Number of channels (1, 2, 5, 7) */ uint8_t format; /* Audio data format */ uint8_t subformat; /* Audio subformat * (maybe should be combined with format? */ }; /* This structure describes the preferred number and size of * audio pipeline buffers for the audio device. Each device * may have unique needs regarding size and qty of buffers, * so this info is queried from the lower-half driver. */ struct ap_buffer_info_s { apb_samp_t nbuffers; /* Preferred qty of buffers */ apb_samp_t buffer_size; /* Preferred size of the buffers */ }; /* This structure describes an Audio Pipeline Buffer */ struct ap_buffer_s { struct dq_entry_s dq_entry; /* Double linked queue entry */ struct audio_info_s i; /* The info for samples in this buffer */ #ifdef CONFIG_AUDIO_MULTI_SESSION FAR void *session; /* Associated session */ #endif apb_samp_t nmaxbytes; /* The maximum number of bytes */ apb_samp_t nbytes; /* The number of bytes used */ apb_samp_t curbyte; /* Next byte to be processed */ apb_samp_t nsamples; /* The number of samples in the buffer */ mutex_t lock; /* Reference locking mutex */ uint16_t flags; /* Buffer flags */ uint16_t crefs; /* Number of reference counts */ FAR uint8_t *samp; /* Offset of the first sample */ }; /* Structure defining the messages passed to a listening audio thread * for dequeuing buffers and other operations. Also used to allocate * and enqueue buffers via the AUDIOIOC_ALLOCBUFFER, AUDIOIOC_FREEBUFFER, * and AUDIOIOC_ENQUEUEBUFFER ioctls. */ struct audio_msg_s { #ifdef CONFIG_AUDIO_MULTI_SESSION FAR void *session; /* Associated channel */ #endif uint16_t msg_id; /* Message ID */ union { FAR void *ptr; /* Buffer being dequeued */ uint32_t data; /* Message data */ } u; }; /* Structure defining the built-in sounds */ #ifdef CONFIG_AUDIO_BUILTIN_SOUNDS struct audio_sound_s { FAR const char *name; /* Name of the sound */ uint32_t id; /* ID of the sound */ uint32_t type; /* Type of sound */ uint32_t size; /* Number of bytes in the sound */ FAR const uint8_t *data; /* Pointer to the data */ }; #endif /* Structure for allocating, freeing and enqueueing audio pipeline * buffers via the AUDIOIOC_ALLOCBUFFER, AUDIOIOC_FREEBUFFER, * and AUDIOIOC_ENQUEUEBUFFER ioctls. */ struct audio_buf_desc_s { #ifdef CONFIG_AUDIO_MULTI_SESSION FAR void *session; /* Associated channel */ #endif apb_samp_t numbytes; /* Number of bytes to allocate */ union { FAR struct ap_buffer_s *buffer; /* Buffer to free / enqueue */ FAR struct ap_buffer_s **pbuffer; /* Pointer to receive allocated buffer */ } u; }; /* Typedef for lower-level to upper-level callback for buffer dequeuing */ #ifdef CONFIG_AUDIO_MULTI_SESSION typedef CODE void (*audio_callback_t)(FAR void *priv, uint16_t reason, FAR struct ap_buffer_s *apb, uint16_t status, FAR void *session); #else typedef CODE void (*audio_callback_t)(FAR void *priv, uint16_t reason, FAR struct ap_buffer_s *apb, uint16_t status); #endif /* This structure is a set a callback functions used to call from the upper- * half, generic Audo driver into lower-half, platform-specific logic that * supports the low-level functionality. */ struct audio_lowerhalf_s; struct audio_ops_s { /* This method is called to retrieve the lower-half device capabilities. * It will be called with device type AUDIO_TYPE_QUERY to request the * overall capabilities, such as to determine the types of devices * supported audio formats supported, etc. * Then it may be called once or more with reported supported device types * to determine the specific capabilities of that device type * (such as MP3 encoder, WMA encoder, PCM output, etc.). */ CODE int (*getcaps)(FAR struct audio_lowerhalf_s *dev, int type, FAR struct audio_caps_s *caps); /* This method is called to bind the lower-level driver to the upper-level * driver and to configure the driver for a specific mode of * operation defined by the parameters selected in supplied device caps * structure. The lower-level device should perform any initialization * needed to prepare for operations in the specified mode. It should not, * however, process any audio data until the start method is called. */ #ifdef CONFIG_AUDIO_MULTI_SESSION CODE int (*configure)(FAR struct audio_lowerhalf_s *dev, FAR void *session, FAR const struct audio_caps_s *caps); #else CODE int (*configure)(FAR struct audio_lowerhalf_s *dev, FAR const struct audio_caps_s *caps); #endif /* This method is called when the driver is closed. The lower half driver * should stop processing audio data, including terminating any active * output generation. It should also disable the audio hardware and put * it into the lowest possible power usage state. * * Any enqueued Audio Pipeline Buffers that have not been * processed / dequeued should be dequeued by this function. */ CODE int (*shutdown)(FAR struct audio_lowerhalf_s *dev); /* Start audio streaming in the configured mode. For input and synthesis * devices, this means it should begin sending streaming audio data. * For output or processing type device, it means it should begin * processing of any enqueued Audio Pipeline Buffers. */ #ifdef CONFIG_AUDIO_MULTI_SESSION CODE int (*start)(FAR struct audio_lowerhalf_s *dev, FAR void *session); #else CODE int (*start)(FAR struct audio_lowerhalf_s *dev); #endif /* Stop audio streaming and/or processing of enqueued * Audio Pipeline Buffers */ #ifndef CONFIG_AUDIO_EXCLUDE_STOP #ifdef CONFIG_AUDIO_MULTI_SESSION CODE int (*stop)(FAR struct audio_lowerhalf_s *dev, FAR void *session); #else CODE int (*stop)(FAR struct audio_lowerhalf_s *dev); #endif #endif /* Pause the audio stream. * Should keep current playback context active in case a resume is issued. * Could be called and then followed by a stop. */ #ifndef CONFIG_AUDIO_EXCLUDE_PAUSE_RESUME #ifdef CONFIG_AUDIO_MULTI_SESSION CODE int (*pause)(FAR struct audio_lowerhalf_s *dev, FAR void *session); #else CODE int (*pause)(FAR struct audio_lowerhalf_s *dev); #endif /* Resumes audio streaming after a pause */ #ifdef CONFIG_AUDIO_MULTI_SESSION CODE int (*resume)(FAR struct audio_lowerhalf_s *dev, FAR void *session); #else CODE int (*resume)(FAR struct audio_lowerhalf_s *dev); #endif #endif /* CONFIG_AUDIO_EXCLUDE_PAUSE_RESUME */ /* Allocate an audio pipeline buffer. This routine provides the * lower-half driver with the opportunity to perform special buffer * allocation if needed, such as allocating from a specific memory * region (DMA-able, etc.). If not supplied, then the top-half * driver will perform a standard kumm_malloc using normal user-space * memory region. */ CODE int (*allocbuffer)(FAR struct audio_lowerhalf_s *dev, FAR struct audio_buf_desc_s *apb); /* Free an audio pipeline buffer. If the lower-level driver * provides an allocbuffer routine, it should also provide the * freebuffer routine to perform the free operation. */ CODE int (*freebuffer)(FAR struct audio_lowerhalf_s *dev, FAR struct audio_buf_desc_s *apb); /* Enqueue a buffer for processing. * This is a non-blocking enqueue operation. * If the lower-half driver's buffer queue is full, then it should return * an error code of -ENOMEM, and the upper-half driver can decide to either * block the calling thread or deal with it in a non-blocking manner. * For each call to enqueuebuffer, the lower-half driver must call * audio_dequeuebuffer when it is finished processing the bufferr, passing * the previously enqueued apb and a dequeue status so that the upper-half * driver can decide if a waiting thread needs to be release, if the * dequeued buffer should be passed to the next block in the * Audio Pipeline, etc. */ CODE int (*enqueuebuffer)(FAR struct audio_lowerhalf_s *dev, FAR struct ap_buffer_s *apb); /* Cancel a previously enqueued buffer. */ CODE int (*cancelbuffer)(FAR struct audio_lowerhalf_s *dev, FAR struct ap_buffer_s *apb); /* Lower-half logic may support platform-specific ioctl commands */ CODE int (*ioctl)(FAR struct audio_lowerhalf_s *dev, int cmd, unsigned long arg); /* Lower-half logic may support platform-specific read commands */ CODE int (*read)(FAR struct audio_lowerhalf_s *dev, FAR char *buffer, size_t buflen); /* Lower-half logic may support platform-specific write commands */ CODE int (*write)(FAR struct audio_lowerhalf_s *dev, FAR const char *buffer, size_t buflen); /* Reserve a session (may only be one per device or may be multiple) for * use by a client. Client software can open audio devices and issue * AUDIOIOC_GETCAPS calls freely, but other operations require a * reservation. A session reservation will assign a context that must * be passed with */ #ifdef CONFIG_AUDIO_MULTI_SESSION CODE int (*reserve)(FAR struct audio_lowerhalf_s *dev, FAR void **psession); #else CODE int (*reserve)(FAR struct audio_lowerhalf_s *dev); #endif /* Release a session. */ #ifdef CONFIG_AUDIO_MULTI_SESSION CODE int (*release)(FAR struct audio_lowerhalf_s *dev, FAR void *session); #else CODE int (*release)(FAR struct audio_lowerhalf_s *dev); #endif }; /* This structure is the generic form of state structure used by lower half * Audio driver. This state structure is passed to the Audio driver when the * driver is initialized. Then, on subsequent callbacks into the lower half * Audio logic, this structure is provided so that the Audio logic can * maintain state information. * * Normally that Audio logic will have its own, custom state structure * that is simply cast to struct audio_lowerhalf_s. In order to perform such * casts, the initial fields of the custom state structure match the initial * fields of the following generic Audio state structure. */ struct audio_lowerhalf_s { /* The first field of this state structure must be a pointer to the Audio * callback structure: */ FAR const struct audio_ops_s *ops; /* The bind data to the upper-half driver used for callbacks of dequeuing * buffer, reporting asynchronous event, reporting errors, etc. */ audio_callback_t upper; /* The private opaque pointer to be passed to upper-layer during * callbacks */ FAR void *priv; /* The custom Audio device state structure may include additional fields * after the pointer to the Audio callback structure. */ }; /**************************************************************************** * Public Data ****************************************************************************/ /**************************************************************************** * Public Function Prototypes ****************************************************************************/ #ifdef __cplusplus #define EXTERN extern "C" extern "C" { #else #define EXTERN extern #endif /**************************************************************************** * "Upper-Half" Audio Driver Interfaces ****************************************************************************/ /**************************************************************************** * Name: audio_register * * Description: * This function binds an instance of a "lower half" Audio driver with the * "upper half" Audio device and registers that device so that can be used * by application code. * * When this function is called, the "lower half" driver should be in the * reset state (as if the shutdown() method had already been called). * * Input Parameters: * name - The name of the audio device. This name will be used to generate * a full path to the driver in the format "/dev/audio/[name]" in the * NuttX filesystem (i.e. the path "/dev/audio" will be prepended to the * supplied device name. The recommended convention is to name Audio * drivers based on the type of functionality they provide, such as * "/dev/audio/pcm0", "/dev/audio/midi0", "/dev/audio/mp30, etc. * dev - A pointer to an instance of lower half audio driver. This instance * is bound to the Audio driver and must persists as long as the driver * persists. * * Returned Value: * Zero on success; a negated errno value on failure. * ****************************************************************************/ int audio_register(FAR const char *name, FAR struct audio_lowerhalf_s *dev); /**************************************************************************** * Name: abp_alloc * * Description: * Allocated an AP Buffer and prepares it for use. * This allocates a dynamically allocated buffer that has no special * DMA capabilities. * * Input Parameters: * bufdesc: Pointer to a buffer descriptor * * Returned Value: * Pointer to the allocated buffer or NULL if no memory. * ****************************************************************************/ int apb_alloc(FAR struct audio_buf_desc_s *bufdesc); /**************************************************************************** * Name: apb_free * * Free's a previously allocated or referenced Audio Pipeline Buffer * ****************************************************************************/ void apb_free(FAR struct ap_buffer_s *apb); /**************************************************************************** * Name: apb_reference * * Claim a reference to an Audio Pipeline Buffer. Each call to apb_reference * will increment the reference count and must have a matching apb_free * call. When the refcount decrements to zero, the buffer will be freed. * ****************************************************************************/ void apb_reference(FAR struct ap_buffer_s *apb); /**************************************************************************** * Platform-Dependent "Lower-Half" Audio Driver Interfaces ****************************************************************************/ #undef EXTERN #ifdef __cplusplus } #endif #endif /* CONFIG_AUDIO */ #endif /* __INCLUDE_NUTTX_AUDIO_AUDIO_H */