RetroArch/audio/drivers/tinyalsa.c
2024-10-01 17:36:33 -07:00

2431 lines
74 KiB
C

/* pcm.c
**
** Copyright 2011, The Android Open Source Project
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in the
** documentation and/or other materials provided with the distribution.
** * Neither the name of The Android Open Source Project nor the names of
** its contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND
** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE
** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
** DAMAGE.
*/
/* RetroArch - A frontend for libretro.
* Copyright (C) 2010-2014 - Hans-Kristian Arntzen
* Copyright (C) 2011-2017 - Daniel De Matteis
* Copyright (C) 2017 - Charlton Head
*
* RetroArch is free software: you can redistribute it and/or modify it under the terms
* of the GNU General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with RetroArch.
* If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <poll.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <time.h>
#include <limits.h>
#include <linux/ioctl.h>
#include <linux/types.h>
#include <retro_inline.h>
#include <retro_endianness.h>
#include "../audio_driver.h"
#include "../../verbosity.h"
/* Implementation tinyalsa pcm */
/** A flag that specifies that the PCM is an output.
* May not be bitwise AND'd with @ref PCM_IN.
* Used in @ref pcm_open.
* @ingroup libtinyalsa-pcm
*/
#define PCM_OUT 0x00000000
/** Specifies that the PCM is an input.
* May not be bitwise AND'd with @ref PCM_OUT.
* Used in @ref pcm_open.
* @ingroup libtinyalsa-pcm
*/
#define PCM_IN 0x10000000
/** Specifies that the PCM will use mmap read and write methods.
* Used in @ref pcm_open.
* @ingroup libtinyalsa-pcm
*/
#define PCM_MMAP 0x00000001
/** Specifies no interrupt requests.
* May only be bitwise AND'd with @ref PCM_MMAP.
* Used in @ref pcm_open.
* @ingroup libtinyalsa-pcm
*/
#define PCM_NOIRQ 0x00000002
/** When set, calls to @ref pcm_write
* for a playback stream will not attempt
* to restart the stream in the case of an
* underflow, but will return -EPIPE instead.
* After the first -EPIPE error, the stream
* is considered to be stopped, and a second
* call to pcm_write will attempt to restart
* the stream.
* Used in @ref pcm_open.
* @ingroup libtinyalsa-pcm
*/
#define PCM_NORESTART 0x00000004
/** Specifies monotonic timestamps.
* Used in @ref pcm_open.
* @ingroup libtinyalsa-pcm
*/
#define PCM_MONOTONIC 0x00000008
/** For inputs, this means the PCM is recording audio samples.
* For outputs, this means the PCM is playing audio samples.
* @ingroup libtinyalsa-pcm
*/
#define PCM_STATE_RUNNING 0x03
/** For inputs, this means an overrun occurred.
* For outputs, this means an underrun occurred.
*/
#define PCM_STATE_XRUN 0x04
/** For outputs, this means audio samples are played.
* A PCM is in a draining state when it is coming to a stop.
*/
#define PCM_STATE_DRAINING 0x05
/** Means a PCM is suspended.
* @ingroup libtinyalsa-pcm
*/
#define PCM_STATE_SUSPENDED 0x07
/** Means a PCM has been disconnected.
* @ingroup libtinyalsa-pcm
*/
#define PCM_STATE_DISCONNECTED 0x08
#define SNDRV_CHMAP_POSITION_MASK 0xffff
#define SNDRV_CHMAP_PHASE_INVERSE (0x01 << 16)
#define SNDRV_CHMAP_DRIVER_SPEC (0x02 << 16)
#define SNDRV_PCM_IOCTL_PVERSION _IOR('A', 0x00, int)
#define SNDRV_PCM_IOCTL_INFO _IOR('A', 0x01, struct snd_pcm_info)
#define SNDRV_PCM_IOCTL_TSTAMP _IOW('A', 0x02, int)
#define SNDRV_PCM_IOCTL_TTSTAMP _IOW('A', 0x03, int)
#define SNDRV_PCM_IOCTL_HW_REFINE _IOWR('A', 0x10, struct snd_pcm_hw_params)
#define SNDRV_PCM_IOCTL_HW_PARAMS _IOWR('A', 0x11, struct snd_pcm_hw_params)
#define SNDRV_PCM_IOCTL_HW_FREE _IO('A', 0x12)
#define SNDRV_PCM_IOCTL_SW_PARAMS _IOWR('A', 0x13, struct snd_pcm_sw_params)
#define SNDRV_PCM_IOCTL_STATUS _IOR('A', 0x20, struct snd_pcm_status)
#define SNDRV_PCM_IOCTL_DELAY _IOR('A', 0x21, snd_pcm_sframes_t)
#define SNDRV_PCM_IOCTL_HWSYNC _IO('A', 0x22)
#define SNDRV_PCM_IOCTL_SYNC_PTR _IOWR('A', 0x23, struct snd_pcm_sync_ptr)
#define SNDRV_PCM_IOCTL_CHANNEL_INFO _IOR('A', 0x32, struct snd_pcm_channel_info)
#define SNDRV_PCM_IOCTL_PREPARE _IO('A', 0x40)
#define SNDRV_PCM_IOCTL_RESET _IO('A', 0x41)
#define SNDRV_PCM_IOCTL_START _IO('A', 0x42)
#define SNDRV_PCM_IOCTL_DROP _IO('A', 0x43)
#define SNDRV_PCM_IOCTL_DRAIN _IO('A', 0x44)
#define SNDRV_PCM_IOCTL_PAUSE _IOW('A', 0x45, int)
#define SNDRV_PCM_IOCTL_REWIND _IOW('A', 0x46, snd_pcm_uframes_t)
#define SNDRV_PCM_IOCTL_RESUME _IO('A', 0x47)
#define SNDRV_PCM_IOCTL_XRUN _IO('A', 0x48)
#define SNDRV_PCM_IOCTL_FORWARD _IOW('A', 0x49, snd_pcm_uframes_t)
#define SNDRV_PCM_IOCTL_WRITEI_FRAMES _IOW('A', 0x50, struct snd_xferi)
#define SNDRV_PCM_IOCTL_READI_FRAMES _IOR('A', 0x51, struct snd_xferi)
#define SNDRV_PCM_IOCTL_WRITEN_FRAMES _IOW('A', 0x52, struct snd_xfern)
#define SNDRV_PCM_IOCTL_READN_FRAMES _IOR('A', 0x53, struct snd_xfern)
#define SNDRV_PCM_IOCTL_LINK _IOW('A', 0x60, int)
#define SNDRV_PCM_IOCTL_UNLINK _IO('A', 0x61)
#define SNDRV_PCM_ACCESS_MMAP_INTERLEAVED (( tinyalsa_snd_pcm_access_t) 0) /* interleaved mmap */
#define SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED (( tinyalsa_snd_pcm_access_t) 1) /* noninterleaved mmap */
#define SNDRV_PCM_ACCESS_MMAP_COMPLEX (( tinyalsa_snd_pcm_access_t) 2) /* complex mmap */
#define SNDRV_PCM_ACCESS_RW_INTERLEAVED (( tinyalsa_snd_pcm_access_t) 3) /* readi/writei */
#define SNDRV_PCM_ACCESS_RW_NONINTERLEAVED (( tinyalsa_snd_pcm_access_t) 4) /* readn/writen */
#define SNDRV_PCM_ACCESS_LAST SNDRV_PCM_ACCESS_RW_NONINTERLEAVED
#define SNDRV_PCM_SUBFORMAT_STD (( tinyalsa_snd_pcm_subformat_t) 0)
#define SNDRV_PCM_SUBFORMAT_LAST SNDRV_PCM_SUBFORMAT_STD
#define SNDRV_PCM_SUBFORMAT_STD (( tinyalsa_snd_pcm_subformat_t) 0)
#define SNDRV_PCM_SUBFORMAT_LAST SNDRV_PCM_SUBFORMAT_STD
#define SNDRV_PCM_INFO_MMAP 0x00000001 /* hardware supports mmap */
#define SNDRV_PCM_INFO_MMAP_VALID 0x00000002 /* period data are valid during transfer */
#define SNDRV_PCM_INFO_DOUBLE 0x00000004 /* Double buffering needed for PCM start/stop */
#define SNDRV_PCM_INFO_BATCH 0x00000010 /* double buffering */
#define SNDRV_PCM_INFO_INTERLEAVED 0x00000100 /* channels are interleaved */
#define SNDRV_PCM_INFO_NONINTERLEAVED 0x00000200 /* channels are not interleaved */
#define SNDRV_PCM_INFO_COMPLEX 0x00000400 /* complex frame organization (mmap only) */
#define SNDRV_PCM_INFO_BLOCK_TRANSFER 0x00010000 /* hardware transfer block of samples */
#define SNDRV_PCM_INFO_OVERRANGE 0x00020000 /* hardware supports ADC (capture) overrange detection */
#define SNDRV_PCM_INFO_RESUME 0x00040000 /* hardware supports stream resume after suspend */
#define SNDRV_PCM_INFO_PAUSE 0x00080000 /* pause ioctl is supported */
#define SNDRV_PCM_INFO_HALF_DUPLEX 0x00100000 /* only half duplex */
#define SNDRV_PCM_INFO_JOINT_DUPLEX 0x00200000 /* playback and capture stream are somewhat correlated */
#define SNDRV_PCM_INFO_SYNC_START 0x00400000 /* pcm support some kind of sync go */
#define SNDRV_PCM_INFO_NO_PERIOD_WAKEUP 0x00800000 /* period wakeup can be disabled */
#define SNDRV_PCM_INFO_HAS_WALL_CLOCK 0x01000000 /* has audio wall clock for audio/system time sync */
#define SNDRV_PCM_INFO_FIFO_IN_FRAMES 0x80000000 /* internal kernel flag - FIFO size is in frames */
#define SNDRV_PCM_STATE_OPEN (( tinyalsa_snd_pcm_state_t) 0) /* stream is open */
#define SNDRV_PCM_STATE_SETUP (( tinyalsa_snd_pcm_state_t) 1) /* stream has a setup */
#define SNDRV_PCM_STATE_PREPARED (( tinyalsa_snd_pcm_state_t) 2) /* stream is ready to start */
#define SNDRV_PCM_STATE_RUNNING (( tinyalsa_snd_pcm_state_t) 3) /* stream is running */
#define SNDRV_PCM_STATE_XRUN (( tinyalsa_snd_pcm_state_t) 4) /* stream reached an xrun */
#define SNDRV_PCM_STATE_DRAINING (( tinyalsa_snd_pcm_state_t) 5) /* stream is draining */
#define SNDRV_PCM_STATE_PAUSED (( tinyalsa_snd_pcm_state_t) 6) /* stream is paused */
#define SNDRV_PCM_STATE_SUSPENDED (( tinyalsa_snd_pcm_state_t) 7) /* hardware is suspended */
#define SNDRV_PCM_STATE_DISCONNECTED (( tinyalsa_snd_pcm_state_t) 8) /* hardware is disconnected */
#define SNDRV_PCM_STATE_LAST SNDRV_PCM_STATE_DISCONNECTED
#define SNDRV_PCM_HW_PARAM_ACCESS 0 /* Access type */
#define SNDRV_PCM_HW_PARAM_FORMAT 1 /* Format */
#define SNDRV_PCM_HW_PARAM_SUBFORMAT 2 /* Subformat */
#define SNDRV_PCM_HW_PARAM_FIRST_MASK SNDRV_PCM_HW_PARAM_ACCESS
#define SNDRV_PCM_HW_PARAM_LAST_MASK SNDRV_PCM_HW_PARAM_SUBFORMAT
#define SNDRV_PCM_HW_PARAM_SAMPLE_BITS 8 /* Bits per sample */
#define SNDRV_PCM_HW_PARAM_FRAME_BITS 9 /* Bits per frame */
#define SNDRV_PCM_HW_PARAM_CHANNELS 10 /* Channels */
#define SNDRV_PCM_HW_PARAM_RATE 11 /* Approx rate */
#define SNDRV_PCM_HW_PARAM_PERIOD_TIME 12 /* Approx distance between interrupts in us */
#define SNDRV_PCM_HW_PARAM_PERIOD_SIZE 13 /* Approx frames between interrupts */
#define SNDRV_PCM_HW_PARAM_PERIOD_BYTES 14 /* Approx bytes between interrupts */
#define SNDRV_PCM_HW_PARAM_PERIODS 15 /* Approx interrupts per buffer */
#define SNDRV_PCM_HW_PARAM_BUFFER_TIME 16 /* Approx duration of buffer in us */
#define SNDRV_PCM_HW_PARAM_BUFFER_SIZE 17 /* Size of buffer in frames */
#define SNDRV_PCM_HW_PARAM_BUFFER_BYTES 18 /* Size of buffer in bytes */
#define SNDRV_PCM_HW_PARAM_TICK_TIME 19 /* Approx tick duration in us */
#define SNDRV_PCM_HW_PARAM_FIRST_INTERVAL SNDRV_PCM_HW_PARAM_SAMPLE_BITS
#define SNDRV_PCM_HW_PARAM_LAST_INTERVAL SNDRV_PCM_HW_PARAM_TICK_TIME
#define SNDRV_PCM_HW_PARAMS_NORESAMPLE (1<<0) /* avoid rate resampling */
#define SNDRV_PCM_HW_PARAMS_EXPORT_BUFFER (1<<1) /* export buffer */
#define SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP (1<<2) /* disable period wakeups */
#define SNDRV_PCM_FORMAT_S8 (( tinyalsa_snd_pcm_format_t) 0)
#define SNDRV_PCM_FORMAT_U8 (( tinyalsa_snd_pcm_format_t) 1)
#define SNDRV_PCM_FORMAT_S16_LE (( tinyalsa_snd_pcm_format_t) 2)
#define SNDRV_PCM_FORMAT_S16_BE (( tinyalsa_snd_pcm_format_t) 3)
#define SNDRV_PCM_FORMAT_U16_LE (( tinyalsa_snd_pcm_format_t) 4)
#define SNDRV_PCM_FORMAT_U16_BE (( tinyalsa_snd_pcm_format_t) 5)
#define SNDRV_PCM_FORMAT_S24_LE (( tinyalsa_snd_pcm_format_t) 6) /* low three bytes */
#define SNDRV_PCM_FORMAT_S24_BE (( tinyalsa_snd_pcm_format_t) 7) /* low three bytes */
#define SNDRV_PCM_FORMAT_U24_LE (( tinyalsa_snd_pcm_format_t) 8) /* low three bytes */
#define SNDRV_PCM_FORMAT_U24_BE (( tinyalsa_snd_pcm_format_t) 9) /* low three bytes */
#define SNDRV_PCM_FORMAT_S32_LE (( tinyalsa_snd_pcm_format_t) 10)
#define SNDRV_PCM_FORMAT_S32_BE (( tinyalsa_snd_pcm_format_t) 11)
#define SNDRV_PCM_FORMAT_U32_LE (( tinyalsa_snd_pcm_format_t) 12)
#define SNDRV_PCM_FORMAT_U32_BE (( tinyalsa_snd_pcm_format_t) 13)
#define SNDRV_PCM_FORMAT_FLOAT_LE (( tinyalsa_snd_pcm_format_t) 14) /* 4-byte float, IEEE-754 32-bit, range -1.0 to 1.0 */
#define SNDRV_PCM_FORMAT_FLOAT_BE (( tinyalsa_snd_pcm_format_t) 15) /* 4-byte float, IEEE-754 32-bit, range -1.0 to 1.0 */
#define SNDRV_PCM_FORMAT_FLOAT64_LE (( tinyalsa_snd_pcm_format_t) 16) /* 8-byte float, IEEE-754 64-bit, range -1.0 to 1.0 */
#define SNDRV_PCM_FORMAT_FLOAT64_BE (( tinyalsa_snd_pcm_format_t) 17) /* 8-byte float, IEEE-754 64-bit, range -1.0 to 1.0 */
#define SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE (( tinyalsa_snd_pcm_format_t) 18) /* IEC-958 subframe, Little Endian */
#define SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE (( tinyalsa_snd_pcm_format_t) 19) /* IEC-958 subframe, Big Endian */
#define SNDRV_PCM_FORMAT_MU_LAW (( tinyalsa_snd_pcm_format_t) 20)
#define SNDRV_PCM_FORMAT_A_LAW (( tinyalsa_snd_pcm_format_t) 21)
#define SNDRV_PCM_FORMAT_IMA_ADPCM (( tinyalsa_snd_pcm_format_t) 22)
#define SNDRV_PCM_FORMAT_MPEG (( tinyalsa_snd_pcm_format_t) 23)
#define SNDRV_PCM_FORMAT_GSM (( tinyalsa_snd_pcm_format_t) 24)
#define SNDRV_PCM_FORMAT_SPECIAL (( tinyalsa_snd_pcm_format_t) 31)
#define SNDRV_PCM_FORMAT_S24_3LE (( tinyalsa_snd_pcm_format_t) 32) /* in three bytes */
#define SNDRV_PCM_FORMAT_S24_3BE (( tinyalsa_snd_pcm_format_t) 33) /* in three bytes */
#define SNDRV_PCM_FORMAT_U24_3LE (( tinyalsa_snd_pcm_format_t) 34) /* in three bytes */
#define SNDRV_PCM_FORMAT_U24_3BE (( tinyalsa_snd_pcm_format_t) 35) /* in three bytes */
#define SNDRV_PCM_FORMAT_S20_3LE (( tinyalsa_snd_pcm_format_t) 36) /* in three bytes */
#define SNDRV_PCM_FORMAT_S20_3BE (( tinyalsa_snd_pcm_format_t) 37) /* in three bytes */
#define SNDRV_PCM_FORMAT_U20_3LE (( tinyalsa_snd_pcm_format_t) 38) /* in three bytes */
#define SNDRV_PCM_FORMAT_U20_3BE (( tinyalsa_snd_pcm_format_t) 39) /* in three bytes */
#define SNDRV_PCM_FORMAT_S18_3LE (( tinyalsa_snd_pcm_format_t) 40) /* in three bytes */
#define SNDRV_PCM_FORMAT_S18_3BE (( tinyalsa_snd_pcm_format_t) 41) /* in three bytes */
#define SNDRV_PCM_FORMAT_U18_3LE (( tinyalsa_snd_pcm_format_t) 42) /* in three bytes */
#define SNDRV_PCM_FORMAT_U18_3BE (( tinyalsa_snd_pcm_format_t) 43) /* in three bytes */
#define SNDRV_PCM_FORMAT_G723_24 (( tinyalsa_snd_pcm_format_t) 44) /* 8 samples in 3 bytes */
#define SNDRV_PCM_FORMAT_G723_24_1B (( tinyalsa_snd_pcm_format_t) 45) /* 1 sample in 1 byte */
#define SNDRV_PCM_FORMAT_G723_40 (( tinyalsa_snd_pcm_format_t) 46) /* 8 Samples in 5 bytes */
#define SNDRV_PCM_FORMAT_G723_40_1B (( tinyalsa_snd_pcm_format_t) 47) /* 1 sample in 1 byte */
#define SNDRV_PCM_FORMAT_DSD_U8 (( tinyalsa_snd_pcm_format_t) 48) /* DSD, 1-byte samples DSD (x8) */
#define SNDRV_PCM_FORMAT_DSD_U16_LE (( tinyalsa_snd_pcm_format_t) 49) /* DSD, 2-byte samples DSD (x16), little endian */
#define SNDRV_PCM_FORMAT_DSD_U32_LE (( tinyalsa_snd_pcm_format_t) 50) /* DSD, 4-byte samples DSD (x32), little endian */
#define SNDRV_PCM_FORMAT_DSD_U16_BE (( tinyalsa_snd_pcm_format_t) 51) /* DSD, 2-byte samples DSD (x16), big endian */
#define SNDRV_PCM_FORMAT_DSD_U32_BE (( tinyalsa_snd_pcm_format_t) 52) /* DSD, 4-byte samples DSD (x32), big endian */
#define SNDRV_PCM_FORMAT_LAST SNDRV_PCM_FORMAT_DSD_U32_BE
#define SNDRV_MASK_MAX 256
#define SNDRV_PCM_SYNC_PTR_HWSYNC (1<<0) /* execute hwsync */
#define SNDRV_PCM_SYNC_PTR_APPL (1<<1) /* get appl_ptr from driver (r/w op) */
#define SNDRV_PCM_SYNC_PTR_AVAIL_MIN (1<<2) /* get avail_min from driver */
#define SNDRV_PCM_MMAP_OFFSET_DATA 0x00000000
#define SNDRV_PCM_MMAP_OFFSET_STATUS 0x80000000
#define SNDRV_PCM_MMAP_OFFSET_CONTROL 0x81000000
/** Audio sample format of a PCM.
* The first letter specifiers whether the sample is signed or unsigned.
* The letter 'S' means signed. The letter 'U' means unsigned.
* The following number is the amount of bits that the sample occupies in memory.
* Following the underscore, specifiers whether the sample is big endian or little endian.
* The letters 'LE' mean little endian.
* The letters 'BE' mean big endian.
* This enumeration is used in the @ref pcm_config structure.
* @ingroup libtinyalsa-pcm
*/
enum pcm_format
{
/** Signed, 8-bit */
PCM_FORMAT_S8 = 1,
/** Signed 16-bit, little endian */
PCM_FORMAT_S16_LE = 0,
/** Signed, 16-bit, big endian */
PCM_FORMAT_S16_BE = 2,
/** Signed, 24-bit (32-bit in memory), little endian */
PCM_FORMAT_S24_LE,
/** Signed, 24-bit (32-bit in memory), big endian */
PCM_FORMAT_S24_BE,
/** Signed, 24-bit, little endian */
PCM_FORMAT_S24_3LE,
/** Signed, 24-bit, big endian */
PCM_FORMAT_S24_3BE,
/** Signed, 32-bit, little endian */
PCM_FORMAT_S32_LE,
/** Signed, 32-bit, big endian */
PCM_FORMAT_S32_BE,
/** Max of the enumeration list, not an actual format. */
PCM_FORMAT_MAX
};
enum
{
SNDRV_PCM_TSTAMP_NONE = 0,
SNDRV_PCM_TSTAMP_ENABLE,
SNDRV_PCM_TSTAMP_LAST = SNDRV_PCM_TSTAMP_ENABLE
};
/** Enumeration of a PCM's hardware parameters.
* Each of these parameters is either a mask or an interval.
* @ingroup libtinyalsa-pcm
*/
enum pcm_param
{
/** A mask that represents the type of read or write method available (e.g. interleaved, mmap). */
PCM_PARAM_ACCESS,
/** A mask that represents the @ref pcm_format available (e.g. @ref PCM_FORMAT_S32_LE) */
PCM_PARAM_FORMAT,
/** A mask that represents the subformat available */
PCM_PARAM_SUBFORMAT,
/** An interval representing the range of sample bits available (e.g. 8 to 32) */
PCM_PARAM_SAMPLE_BITS,
/** An interval representing the range of frame bits available (e.g. 8 to 64) */
PCM_PARAM_FRAME_BITS,
/** An interval representing the range of channels available (e.g. 1 to 2) */
PCM_PARAM_CHANNELS,
/** An interval representing the range of rates available (e.g. 44100 to 192000) */
PCM_PARAM_RATE,
PCM_PARAM_PERIOD_TIME,
/** The number of frames in a period */
PCM_PARAM_PERIOD_SIZE,
/** The number of bytes in a period */
PCM_PARAM_PERIOD_BYTES,
/** The number of periods for a PCM */
PCM_PARAM_PERIODS,
PCM_PARAM_BUFFER_TIME,
PCM_PARAM_BUFFER_SIZE,
PCM_PARAM_BUFFER_BYTES,
PCM_PARAM_TICK_TIME
}; /* enum pcm_param */
/* channel positions */
enum
{
SNDRV_CHMAP_UNKNOWN = 0,
SNDRV_CHMAP_NA, /* N/A, silent */
SNDRV_CHMAP_MONO, /* mono stream */
/* this follows the alsa-lib mixer channel value + 3 */
SNDRV_CHMAP_FL, /* front left */
SNDRV_CHMAP_FR, /* front right */
SNDRV_CHMAP_RL, /* rear left */
SNDRV_CHMAP_RR, /* rear right */
SNDRV_CHMAP_FC, /* front center */
SNDRV_CHMAP_LFE, /* LFE */
SNDRV_CHMAP_SL, /* side left */
SNDRV_CHMAP_SR, /* side right */
SNDRV_CHMAP_RC, /* rear center */
/* new definitions */
SNDRV_CHMAP_FLC, /* front left center */
SNDRV_CHMAP_FRC, /* front right center */
SNDRV_CHMAP_RLC, /* rear left center */
SNDRV_CHMAP_RRC, /* rear right center */
SNDRV_CHMAP_FLW, /* front left wide */
SNDRV_CHMAP_FRW, /* front right wide */
SNDRV_CHMAP_FLH, /* front left high */
SNDRV_CHMAP_FCH, /* front center high */
SNDRV_CHMAP_FRH, /* front right high */
SNDRV_CHMAP_TC, /* top center */
SNDRV_CHMAP_TFL, /* top front left */
SNDRV_CHMAP_TFR, /* top front right */
SNDRV_CHMAP_TFC, /* top front center */
SNDRV_CHMAP_TRL, /* top rear left */
SNDRV_CHMAP_TRR, /* top rear right */
SNDRV_CHMAP_TRC, /* top rear center */
/* new definitions for UAC2 */
SNDRV_CHMAP_TFLC, /* top front left center */
SNDRV_CHMAP_TFRC, /* top front right center */
SNDRV_CHMAP_TSL, /* top side left */
SNDRV_CHMAP_TSR, /* top side right */
SNDRV_CHMAP_LLFE, /* left LFE */
SNDRV_CHMAP_RLFE, /* right LFE */
SNDRV_CHMAP_BC, /* bottom center */
SNDRV_CHMAP_BLC, /* bottom left center */
SNDRV_CHMAP_BRC, /* bottom right center */
SNDRV_CHMAP_LAST = SNDRV_CHMAP_BRC
};
enum
{
SNDRV_PCM_TSTAMP_TYPE_GETTIMEOFDAY = 0, /* gettimeofday equivalent */
SNDRV_PCM_TSTAMP_TYPE_MONOTONIC, /* posix_clock_monotonic equivalent */
SNDRV_PCM_TSTAMP_TYPE_MONOTONIC_RAW, /* monotonic_raw (no NTP) */
SNDRV_PCM_TSTAMP_TYPE_LAST = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC_RAW
};
typedef unsigned long snd_pcm_uframes_t;
typedef signed long snd_pcm_sframes_t;
typedef int snd_pcm_hw_param_t;
typedef int __bitwise tinyalsa_snd_pcm_access_t;
typedef int __bitwise tinyalsa_snd_pcm_subformat_t;
typedef int __bitwise tinyalsa_snd_pcm_state_t;
typedef int __bitwise tinyalsa_snd_pcm_format_t;
/** A bit mask of 256 bits (32 bytes) that describes some hardware parameters of a PCM */
struct pcm_mask
{
/** bits of the bit mask */
unsigned int bits[32 / sizeof(unsigned int)];
};
union snd_pcm_sync_id
{
unsigned char id[16];
unsigned short id16[8];
unsigned int id32[4];
};
struct snd_pcm_mmap_status
{
tinyalsa_snd_pcm_state_t state; /* RO: state - SNDRV_PCM_STATE_XXXX */
int pad1; /* Needed for 64 bit alignment */
snd_pcm_uframes_t hw_ptr; /* RO: hw ptr (0...boundary-1) */
struct timespec tstamp; /* Timestamp */
tinyalsa_snd_pcm_state_t suspended_state; /* RO: suspended stream state */
struct timespec audio_tstamp; /* from sample counter or wall clock */
};
struct snd_pcm_info
{
unsigned int device; /* RO/WR (control): device number */
unsigned int subdevice; /* RO/WR (control): subdevice number */
int stream; /* RO/WR (control): stream direction */
int card; /* R: card number */
unsigned char id[64]; /* ID (user selectable) */
unsigned char name[80]; /* name of this device */
unsigned char subname[32]; /* subdevice name */
int dev_class; /* SNDRV_PCM_CLASS_* */
int dev_subclass; /* SNDRV_PCM_SUBCLASS_* */
unsigned int subdevices_count;
unsigned int subdevices_avail;
union snd_pcm_sync_id sync; /* hardware synchronization ID */
unsigned char reserved[64]; /* reserved for future... */
};
struct snd_interval
{
unsigned int min, max;
unsigned int openmin:1,
openmax:1,
integer:1,
empty:1;
};
struct snd_mask
{
__u32 bits[(SNDRV_MASK_MAX+31)/32];
};
struct snd_pcm_sw_params
{
int tstamp_mode; /* timestamp mode */
unsigned int period_step;
unsigned int sleep_min; /* min ticks to sleep */
snd_pcm_uframes_t avail_min; /* min avail frames for wakeup */
snd_pcm_uframes_t xfer_align; /* obsolete: xfer size need to be a multiple */
snd_pcm_uframes_t start_threshold; /* min hw_avail frames for automatic start */
snd_pcm_uframes_t stop_threshold; /* min avail frames for automatic stop */
snd_pcm_uframes_t silence_threshold; /* min distance from noise for silence filling */
snd_pcm_uframes_t silence_size; /* silence block size */
snd_pcm_uframes_t boundary; /* pointers wrap point */
unsigned int proto; /* protocol version */
unsigned int tstamp_type; /* timestamp type (req. proto >= 2.0.12) */
unsigned char reserved[56]; /* reserved for future */
};
struct snd_pcm_hw_params
{
unsigned int flags;
struct snd_mask masks[SNDRV_PCM_HW_PARAM_LAST_MASK -
SNDRV_PCM_HW_PARAM_FIRST_MASK + 1];
struct snd_mask mres[5]; /* reserved masks */
struct snd_interval intervals[SNDRV_PCM_HW_PARAM_LAST_INTERVAL -
SNDRV_PCM_HW_PARAM_FIRST_INTERVAL + 1];
struct snd_interval ires[9]; /* reserved intervals */
unsigned int rmask; /* W: requested masks */
unsigned int cmask; /* R: changed masks */
unsigned int info; /* R: Info flags for returned setup */
unsigned int msbits; /* R: used most significant bits */
unsigned int rate_num; /* R: rate numerator */
unsigned int rate_den; /* R: rate denominator */
snd_pcm_uframes_t fifo_size; /* R: chip FIFO size in frames */
unsigned char reserved[64]; /* reserved for future */
};
/** Encapsulates the hardware and software parameters of a PCM.
* @ingroup libtinyalsa-pcm
*/
struct pcm_config
{
/** The number of channels in a frame */
unsigned int channels;
/** The number of frames per second */
unsigned int rate;
/** The number of frames in a period */
unsigned int period_size;
/** The number of periods in a PCM */
unsigned int period_count;
/** The sample format of a PCM */
enum pcm_format format;
/* Values to use for the ALSA start, stop and silence thresholds. Setting
* any one of these values to 0 will cause the default tinyalsa values to be
* used instead. Tinyalsa defaults are as follows.
*
* start_threshold : period_count * period_size
* stop_threshold : period_count * period_size
* silence_threshold : 0
*/
/** The minimum number of frames required to start the PCM */
unsigned int start_threshold;
/** The minimum number of frames required to stop the PCM */
unsigned int stop_threshold;
/** The minimum number of frames to silence the PCM */
unsigned int silence_threshold;
};
struct snd_pcm_mmap_control
{
snd_pcm_uframes_t appl_ptr; /* RW: appl ptr (0...boundary-1) */
snd_pcm_uframes_t avail_min; /* RW: min available frames for wakeup */
};
struct snd_pcm_sync_ptr
{
unsigned int flags;
union
{
struct snd_pcm_mmap_status status;
unsigned char reserved[64];
} s;
union
{
struct snd_pcm_mmap_control control;
unsigned char reserved[64];
} c;
};
struct snd_xferi
{
snd_pcm_sframes_t result;
void *buf;
snd_pcm_uframes_t frames;
};
struct snd_xfern
{
snd_pcm_sframes_t result;
void * *bufs;
snd_pcm_uframes_t frames;
};
struct snd_pcm_status
{
tinyalsa_snd_pcm_state_t state; /* stream state */
struct timespec trigger_tstamp; /* time when stream was started/stopped/paused */
struct timespec tstamp; /* reference timestamp */
snd_pcm_uframes_t appl_ptr; /* appl ptr */
snd_pcm_uframes_t hw_ptr; /* hw ptr */
snd_pcm_sframes_t delay; /* current delay in frames */
snd_pcm_uframes_t avail; /* number of frames available */
snd_pcm_uframes_t avail_max; /* max frames available on hw since last status */
snd_pcm_uframes_t overrange; /* count of ADC (capture) overrange detections from last status */
tinyalsa_snd_pcm_state_t suspended_state; /* suspended stream state */
__u32 reserved_alignment; /* must be filled with zero */
struct timespec audio_tstamp; /* from sample counter or wall clock */
unsigned char reserved[56-sizeof(struct timespec)]; /* must be filled with zero */
};
struct pcm_params;
#define TINYALSA_CHANNELS_MAX 32U
#define TINYALSA_CHANNELS_MIN 1U
#define TINYALSA_FRAMES_MAX (ULONG_MAX / (TINYALSA_CHANNELS_MAX * 4))
#define PARAM_MAX SNDRV_PCM_HW_PARAM_LAST_INTERVAL
#define SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP (1<<2)
static INLINE int param_is_mask(int p)
{
return (p >= SNDRV_PCM_HW_PARAM_FIRST_MASK) &&
(p <= SNDRV_PCM_HW_PARAM_LAST_MASK);
}
static INLINE int param_is_interval(int p)
{
return (p >= SNDRV_PCM_HW_PARAM_FIRST_INTERVAL) &&
(p <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL);
}
static INLINE const struct snd_interval *param_get_interval(const struct snd_pcm_hw_params *p, int n)
{
return &(p->intervals[n - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]);
}
static INLINE struct snd_interval *param_to_interval(struct snd_pcm_hw_params *p, int n)
{
return &(p->intervals[n - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]);
}
static INLINE struct snd_mask *param_to_mask(struct snd_pcm_hw_params *p, int n)
{
return &(p->masks[n - SNDRV_PCM_HW_PARAM_FIRST_MASK]);
}
static void param_set_mask(struct snd_pcm_hw_params *p, int n, unsigned int bit)
{
if (bit >= SNDRV_MASK_MAX)
return;
if (param_is_mask(n))
{
struct snd_mask *m = param_to_mask(p, n);
m->bits[0] = 0;
m->bits[1] = 0;
m->bits[bit >> 5] |= (1 << (bit & 31));
}
}
static void param_set_min(struct snd_pcm_hw_params *p, int n, unsigned int val)
{
if (param_is_interval(n))
{
struct snd_interval *i = param_to_interval(p, n);
i->min = val;
}
}
static void param_set_int(struct snd_pcm_hw_params *p, int n, unsigned int val)
{
if (param_is_interval(n))
{
struct snd_interval *i = param_to_interval(p, n);
i->min = val;
i->max = val;
i->integer = 1;
}
}
static unsigned int param_get_int(struct snd_pcm_hw_params *p, int n)
{
if (param_is_interval(n))
{
struct snd_interval *i = param_to_interval(p, n);
if (i->integer)
return i->max;
}
return 0;
}
static void param_init(struct snd_pcm_hw_params *p)
{
int n;
memset(p, 0, sizeof(*p));
for (n = SNDRV_PCM_HW_PARAM_FIRST_MASK;
n <= SNDRV_PCM_HW_PARAM_LAST_MASK; n++)
{
struct snd_mask *m = param_to_mask(p, n);
m->bits[0] = ~0;
m->bits[1] = ~0;
}
for (n = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL;
n <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; n++)
{
struct snd_interval *i = param_to_interval(p, n);
i->min = 0;
i->max = ~0;
}
p->rmask = ~0U;
p->cmask = 0;
p->info = ~0U;
}
static unsigned int pcm_format_to_alsa(enum pcm_format format)
{
switch (format)
{
case PCM_FORMAT_S8:
return SNDRV_PCM_FORMAT_S8;
default:
case PCM_FORMAT_S16_LE:
return SNDRV_PCM_FORMAT_S16_LE;
case PCM_FORMAT_S16_BE:
return SNDRV_PCM_FORMAT_S16_BE;
case PCM_FORMAT_S24_LE:
return SNDRV_PCM_FORMAT_S24_LE;
case PCM_FORMAT_S24_BE:
return SNDRV_PCM_FORMAT_S24_BE;
case PCM_FORMAT_S24_3LE:
return SNDRV_PCM_FORMAT_S24_3LE;
case PCM_FORMAT_S24_3BE:
return SNDRV_PCM_FORMAT_S24_3BE;
case PCM_FORMAT_S32_LE:
return SNDRV_PCM_FORMAT_S32_LE;
case PCM_FORMAT_S32_BE:
return SNDRV_PCM_FORMAT_S32_BE;
}
}
#define PCM_ERROR_MAX 128
/** A PCM handle.
* @ingroup libtinyalsa-pcm
*/
struct pcm
{
/** The PCM's file descriptor */
int fd;
/** Flags that were passed to @ref pcm_open */
unsigned int flags;
/** Whether the PCM is running or not */
unsigned int running:1;
/** Whether or not the PCM has been prepared */
unsigned int prepared:1;
/** The number of underruns that have occurred */
int underruns;
/** Size of the buffer */
unsigned int buffer_size;
/** The boundary for ring buffer pointers */
unsigned int boundary;
/** Description of the last error that occurred */
char error[PCM_ERROR_MAX];
/** Configuration that was passed to @ref pcm_open */
struct pcm_config config;
struct snd_pcm_mmap_status *mmap_status;
struct snd_pcm_mmap_control *mmap_control;
struct snd_pcm_sync_ptr *sync_ptr;
void *mmap_buffer;
unsigned int noirq_frames_per_msec;
/** The delay of the PCM, in terms of frames */
long pcm_delay;
/** The subdevice corresponding to the PCM */
unsigned int subdevice;
};
/** Gets the buffer size of the PCM.
* @param pcm A PCM handle.
* @return The buffer size of the PCM.
* @ingroup libtinyalsa-pcm
*/
static unsigned int pcm_get_buffer_size(const struct pcm *pcm)
{
return pcm->buffer_size;
}
#if 0
/* Unused for now */
/** Gets the channel count of the PCM.
* @param pcm A PCM handle.
* @return The channel count of the PCM.
* @ingroup libtinyalsa-pcm
*/
static unsigned int pcm_get_channels(const struct pcm *pcm)
{
return pcm->config.channels;
}
/** Gets the PCM configuration.
* @param pcm A PCM handle.
* @return The PCM configuration.
* This function only returns NULL if
* @p pcm is NULL.
* @ingroup libtinyalsa-pcm
* */
static const struct pcm_config * pcm_get_config(const struct pcm *pcm)
{
if (!pcm)
return NULL;
return &pcm->config;
}
/** Gets the rate of the PCM.
* The rate is given in frames per second.
* @param pcm A PCM handle.
* @return The rate of the PCM.
* @ingroup libtinyalsa-pcm
*/
static unsigned int pcm_get_rate(const struct pcm *pcm)
{
return pcm->config.rate;
}
/** Gets the format of the PCM.
* @param pcm A PCM handle.
* @return The format of the PCM.
* @ingroup libtinyalsa-pcm
*/
static enum pcm_format pcm_get_format(const struct pcm *pcm)
{
return pcm->config.format;
}
/** Gets the file descriptor of the PCM.
* Useful for extending functionality of the PCM when needed.
* @param pcm A PCM handle.
* @return The file descriptor of the PCM.
* @ingroup libtinyalsa-pcm
*/
static int pcm_get_file_descriptor(const struct pcm *pcm)
{
return pcm->fd;
}
/** Gets the error message for the last error that occurred.
* If no error occurred and this function is called, the results are undefined.
* @param pcm A PCM handle.
* @return The error message of the last error that occurred.
* @ingroup libtinyalsa-pcm
*/
static const char* pcm_get_error(const struct pcm *pcm)
{
return pcm->error;
}
/** Gets the subdevice on which the pcm has been opened.
* @param pcm A PCM handle.
* @return The subdevice on which the pcm has been opened */
static unsigned int pcm_get_subdevice(const struct pcm *pcm)
{
return pcm->subdevice;
}
/** Determines how many frames of a PCM can fit into a number of bytes.
* @param pcm A PCM handle.
* @param bytes The number of bytes.
* @return The number of frames that may fit into @p bytes
* @ingroup libtinyalsa-pcm
*/
static unsigned int pcm_bytes_to_frames(const struct pcm *pcm, unsigned int bytes)
{
return bytes / (pcm->config.channels *
(pcm_format_to_bits(pcm->config.format) >> 3));
}
#endif
/** Determines the number of bits occupied by a @ref pcm_format.
* @param format A PCM format.
* @return The number of bits associated with @p format
* @ingroup libtinyalsa-pcm
*/
unsigned int pcm_format_to_bits(enum pcm_format format)
{
switch (format)
{
case PCM_FORMAT_S32_LE:
case PCM_FORMAT_S32_BE:
case PCM_FORMAT_S24_LE:
case PCM_FORMAT_S24_BE:
return 32;
case PCM_FORMAT_S24_3LE:
case PCM_FORMAT_S24_3BE:
return 24;
default:
case PCM_FORMAT_S16_LE:
case PCM_FORMAT_S16_BE:
return 16;
case PCM_FORMAT_S8:
return 8;
}
}
/** Determines how many bytes are occupied by a number of frames of a PCM.
* @param pcm A PCM handle.
* @param frames The number of frames of a PCM.
* @return The bytes occupied by @p frames.
* @ingroup libtinyalsa-pcm
*/
static unsigned int pcm_frames_to_bytes(const struct pcm *pcm, unsigned int frames)
{
return frames * pcm->config.channels *
(pcm_format_to_bits(pcm->config.format) >> 3);
}
/** Sets the PCM configuration.
* @param pcm A PCM handle.
* @param config The configuration to use for the
* PCM. This parameter may be NULL, in which case
* the default configuration is used.
* @returns Zero on success, a negative errno value
* on failure.
* @ingroup libtinyalsa-pcm
* */
static int pcm_set_config(struct pcm *pcm, const struct pcm_config *config)
{
struct snd_pcm_sw_params sparams;
struct snd_pcm_hw_params params;
if (!pcm)
return -EFAULT;
if (config)
pcm->config = *config;
else
{
config = &pcm->config;
pcm->config.channels = 2;
pcm->config.rate = 48000;
pcm->config.period_size = 1024;
pcm->config.period_count = 4;
pcm->config.format = PCM_FORMAT_S16_LE;
pcm->config.start_threshold = config->period_count * config->period_size;
pcm->config.stop_threshold = config->period_count * config->period_size;
pcm->config.silence_threshold = 0;
}
param_init(&params);
param_set_mask(&params, SNDRV_PCM_HW_PARAM_FORMAT,
pcm_format_to_alsa(config->format));
param_set_mask(&params, SNDRV_PCM_HW_PARAM_SUBFORMAT,
SNDRV_PCM_SUBFORMAT_STD);
param_set_min(&params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, config->period_size);
param_set_int(&params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
pcm_format_to_bits(config->format));
param_set_int(&params, SNDRV_PCM_HW_PARAM_FRAME_BITS,
pcm_format_to_bits(config->format) * config->channels);
param_set_int(&params, SNDRV_PCM_HW_PARAM_CHANNELS,
config->channels);
param_set_int(&params, SNDRV_PCM_HW_PARAM_PERIODS, config->period_count);
param_set_int(&params, SNDRV_PCM_HW_PARAM_RATE, config->rate);
if (pcm->flags & PCM_NOIRQ)
{
if (!(pcm->flags & PCM_MMAP))
{
RARCH_ERR("[TINYALSA]: noirq only currently supported with mmap().");
return -EINVAL;
}
params.flags |= SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP;
pcm->noirq_frames_per_msec = config->rate / 1000;
}
if (pcm->flags & PCM_MMAP)
param_set_mask(&params, SNDRV_PCM_HW_PARAM_ACCESS,
SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
else
param_set_mask(&params, SNDRV_PCM_HW_PARAM_ACCESS,
SNDRV_PCM_ACCESS_RW_INTERLEAVED);
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_HW_PARAMS, &params))
{
RARCH_ERR("[TINYALSA]: cannot set HW params.");
return -errno;
}
/* get our refined hw_params */
pcm->config.period_size = param_get_int(&params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
pcm->config.period_count = param_get_int(&params, SNDRV_PCM_HW_PARAM_PERIODS);
pcm->buffer_size = config->period_count * config->period_size;
if (pcm->flags & PCM_MMAP)
{
pcm->mmap_buffer = mmap(NULL, pcm_frames_to_bytes(pcm, pcm->buffer_size),
PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, pcm->fd, 0);
if (pcm->mmap_buffer == MAP_FAILED)
{
RARCH_ERR("[TINYALSA]: failed to mmap buffer %d bytes\n",
pcm_frames_to_bytes(pcm, pcm->buffer_size));
return -errno;
}
}
memset(&sparams, 0, sizeof(sparams));
sparams.tstamp_mode = SNDRV_PCM_TSTAMP_ENABLE;
sparams.period_step = 1;
sparams.avail_min = 1;
if (!config->start_threshold)
{
if (pcm->flags & PCM_IN)
pcm->config.start_threshold = sparams.start_threshold = 1;
else
pcm->config.start_threshold = sparams.start_threshold =
config->period_count * config->period_size / 2;
} else
sparams.start_threshold = config->start_threshold;
/* pick a high stop threshold - todo: does this need further tuning */
if (!config->stop_threshold)
{
if (pcm->flags & PCM_IN)
pcm->config.stop_threshold = sparams.stop_threshold =
config->period_count * config->period_size * 10;
else
pcm->config.stop_threshold = sparams.stop_threshold =
config->period_count * config->period_size;
}
else
sparams.stop_threshold = config->stop_threshold;
sparams.xfer_align = config->period_size / 2; /* needed for old kernels */
sparams.silence_size = 0;
sparams.silence_threshold = config->silence_threshold;
pcm->boundary = sparams.boundary = pcm->buffer_size;
while (pcm->boundary * 2 <= INT_MAX - pcm->buffer_size)
pcm->boundary *= 2;
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams))
{
RARCH_ERR("[TINYALSA]: Cannot set HW params.\n");
return -errno;
}
return 0;
}
static int pcm_sync_ptr(struct pcm *pcm, int flags)
{
if (pcm->sync_ptr)
{
pcm->sync_ptr->flags = flags;
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SYNC_PTR, pcm->sync_ptr) >= 0)
return 0;
}
return -1;
}
static int pcm_hw_mmap_status(struct pcm *pcm)
{
int page_size;
if (pcm->sync_ptr)
return 0;
page_size = sysconf(_SC_PAGE_SIZE);
pcm->mmap_status = (struct snd_pcm_mmap_status*)
mmap(NULL, page_size, PROT_READ, MAP_FILE | MAP_SHARED,
pcm->fd, SNDRV_PCM_MMAP_OFFSET_STATUS);
if (pcm->mmap_status == MAP_FAILED)
pcm->mmap_status = NULL;
if (!pcm->mmap_status)
goto mmap_error;
pcm->mmap_control = (struct snd_pcm_mmap_control*)
mmap(NULL, (size_t)page_size, PROT_READ | PROT_WRITE,
MAP_FILE | MAP_SHARED, pcm->fd, SNDRV_PCM_MMAP_OFFSET_CONTROL);
if (pcm->mmap_control == MAP_FAILED)
pcm->mmap_control = NULL;
if (!pcm->mmap_control)
{
munmap(pcm->mmap_status, page_size);
pcm->mmap_status = NULL;
goto mmap_error;
}
pcm->mmap_control->avail_min = 1;
return 0;
mmap_error:
pcm->sync_ptr = (struct snd_pcm_sync_ptr*)
calloc(1, sizeof(*pcm->sync_ptr));
if (!pcm->sync_ptr)
return -ENOMEM;
pcm->mmap_status = &pcm->sync_ptr->s.status;
pcm->mmap_control = &pcm->sync_ptr->c.control;
pcm->mmap_control->avail_min = 1;
pcm_sync_ptr(pcm, 0);
return 0;
}
static void pcm_hw_munmap_status(struct pcm *pcm)
{
if (pcm->sync_ptr)
{
free(pcm->sync_ptr);
pcm->sync_ptr = NULL;
}
else
{
int page_size = sysconf(_SC_PAGE_SIZE);
if (pcm->mmap_status)
munmap(pcm->mmap_status, page_size);
if (pcm->mmap_control)
munmap(pcm->mmap_control, page_size);
}
pcm->mmap_status = NULL;
pcm->mmap_control = NULL;
}
#if 0
/* Unused for now */
static int pcm_areas_copy(struct pcm *pcm, unsigned int pcm_offset,
char *buf, unsigned int src_offset,
unsigned int frames)
{
int size_bytes = pcm_frames_to_bytes(pcm, frames);
int pcm_offset_bytes = pcm_frames_to_bytes(pcm, pcm_offset);
int src_offset_bytes = pcm_frames_to_bytes(pcm, src_offset);
/* interleaved only atm */
if (pcm->flags & PCM_IN)
memcpy(buf + src_offset_bytes,
(char*)pcm->mmap_buffer + pcm_offset_bytes,
size_bytes);
else
memcpy((char*)pcm->mmap_buffer + pcm_offset_bytes,
buf + src_offset_bytes,
size_bytes);
return 0;
}
#endif
static INLINE int pcm_mmap_capture_avail(struct pcm *pcm)
{
int avail = pcm->mmap_status->hw_ptr - pcm->mmap_control->appl_ptr;
if (avail < 0)
avail += pcm->boundary;
return avail;
}
static INLINE int pcm_mmap_playback_avail(struct pcm *pcm)
{
int avail = pcm->mmap_status->hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr;
if (avail < 0)
avail += pcm->boundary;
else if (avail >= (int)pcm->boundary)
avail -= pcm->boundary;
return avail;
}
static INLINE int pcm_mmap_avail(struct pcm *pcm)
{
pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC);
if (pcm->flags & PCM_IN)
return pcm_mmap_capture_avail(pcm);
return pcm_mmap_playback_avail(pcm);
}
#if 0
/* Unused for now */
static int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset,
unsigned int *frames)
{
unsigned int continuous, copy_frames, avail;
/* return the mmap buffer */
*areas = pcm->mmap_buffer;
/* and the application offset in frames */
*offset = pcm->mmap_control->appl_ptr % pcm->buffer_size;
avail = pcm_mmap_avail(pcm);
if (avail > pcm->buffer_size)
avail = pcm->buffer_size;
continuous = pcm->buffer_size - *offset;
/* we can only copy frames if the are available and continuous */
copy_frames = *frames;
if (copy_frames > avail)
copy_frames = avail;
if (copy_frames > continuous)
copy_frames = continuous;
*frames = copy_frames;
return 0;
}
static int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames)
{
int ret;
/* not used */
(void) offset;
/* update the application pointer in userspace and kernel */
pcm_mmap_appl_forward(pcm, frames);
ret = pcm_sync_ptr(pcm, 0);
if (ret != 0)
return ret;
return frames;
}
static void pcm_mmap_appl_forward(struct pcm *pcm, int frames)
{
unsigned int appl_ptr = pcm->mmap_control->appl_ptr;
appl_ptr += frames;
/* check for boundary wrap */
if (appl_ptr > pcm->boundary)
appl_ptr -= pcm->boundary;
pcm->mmap_control->appl_ptr = appl_ptr;
}
/** Returns available frames in pcm buffer and corresponding time stamp.
* The clock is CLOCK_MONOTONIC if flag @ref PCM_MONOTONIC was specified in @ref pcm_open,
* otherwise the clock is CLOCK_REALTIME.
* For an input stream, frames available are frames ready for the application to read.
* For an output stream, frames available are the number of empty frames available for the application to write.
* Only available for PCMs opened with the @ref PCM_MMAP flag.
* @param pcm A PCM handle.
* @param avail The number of available frames
* @param tstamp The timestamp
* @return On success, zero is returned; on failure, negative one.
*/
static int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail,
struct timespec *tstamp)
{
int frames;
int rc;
snd_pcm_uframes_t hw_ptr;
if (!pcm_is_ready(pcm))
return -1;
rc = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL|SNDRV_PCM_SYNC_PTR_HWSYNC);
if (rc < 0)
return -1;
if ((pcm->mmap_status->state != PCM_STATE_RUNNING) &&
(pcm->mmap_status->state != PCM_STATE_DRAINING))
return -1;
*tstamp = pcm->mmap_status->tstamp;
if (tstamp->tv_sec == 0 && tstamp->tv_nsec == 0)
return -1;
hw_ptr = pcm->mmap_status->hw_ptr;
if (pcm->flags & PCM_IN)
frames = hw_ptr - pcm->mmap_control->appl_ptr;
else
frames = hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr;
if (frames < 0)
return -1;
*avail = (unsigned int)frames;
return 0;
}
#endif
/** Checks if a PCM file has been opened without error.
* @param pcm A PCM handle.
* May be NULL.
* @return If a PCM's file descriptor is not valid or the pointer is NULL, it returns zero.
* Otherwise, the function returns one.
* @ingroup libtinyalsa-pcm
*/
static int pcm_is_ready(const struct pcm *pcm)
{
if (pcm)
return pcm->fd >= 0;
return 0;
}
/** Prepares a PCM, if it has not been prepared already.
* @param pcm A PCM handle.
* @return On success, zero; on failure, a negative number.
* @ingroup libtinyalsa-pcm
*/
static int pcm_prepare(struct pcm *pcm)
{
if (pcm->prepared)
return 0;
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_PREPARE) < 0)
{
RARCH_ERR("[TINYALSA]: Cannot prepare channel.\n");
return -1;
}
pcm->prepared = 1;
return 0;
}
/** Writes audio samples to PCM.
* If the PCM has not been started, it is started in this function.
* This function is only valid for PCMs opened with the @ref PCM_OUT flag.
* This function is not valid for PCMs opened with the @ref PCM_MMAP flag.
* @param pcm A PCM handle.
* @param data The audio sample array
* @param frame_count The number of frames occupied by the sample array.
* This value should not be greater than @ref TINYALSA_FRAMES_MAX
* or INT_MAX.
* @return On success, this function returns the number of frames written; otherwise, a negative number.
* @ingroup libtinyalsa-pcm
*/
static int pcm_writei(struct pcm *pcm, const void *data, unsigned int frame_count)
{
struct snd_xferi x;
if (pcm->flags & PCM_IN)
return -EINVAL;
#if UINT_MAX > TINYALSA_FRAMES_MAX
if (frame_count > TINYALSA_FRAMES_MAX)
return -EINVAL;
#endif
if (frame_count > INT_MAX)
return -EINVAL;
x.buf = (void*)data;
x.frames = frame_count;
x.result = 0;
restart:
if (!pcm->running)
{
int prepare_error = pcm_prepare(pcm);
if (prepare_error)
return prepare_error;
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x))
{
RARCH_ERR("[TINYALSA]: Cannot write initial data.\n");
return -1;
}
pcm->running = 1;
return 0;
}
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x))
{
pcm->prepared = 0;
pcm->running = 0;
if (errno == EPIPE)
{
/* we failed to make our window -- try to restart if we are
* allowed to do so. Otherwise, simply allow the EPIPE error to
* propagate up to the app level */
pcm->underruns++;
if (pcm->flags & PCM_NORESTART)
return -EPIPE;
goto restart;
}
#if 0
/* This tends to spam a lot */
RARCH_ERR("[TINYALSA]: Cannot write stream data.\n");
#endif
return -1;
}
return x.result;
}
#if 0
/* Unused for now */
/** Starts a PCM.
* If the PCM has not been prepared,
* it is prepared in this function.
* @param pcm A PCM handle.
* @return On success, zero; on failure, a negative number.
* @ingroup libtinyalsa-pcm
*/
static int pcm_start(struct pcm *pcm)
{
int prepare_error = pcm_prepare(pcm);
if (prepare_error)
return prepare_error;
if (pcm->flags & PCM_MMAP)
pcm_sync_ptr(pcm, 0);
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_START) < 0)
{
RARCH_ERR("[TINYALSA]: Cannot start channel.\n");
return -1;
}
pcm->running = 1;
return 0;
}
/** Reads audio samples from PCM.
* If the PCM has not been started, it is started in this function.
* This function is only valid for PCMs opened with the @ref PCM_IN flag.
* This function is not valid for PCMs opened with the @ref PCM_MMAP flag.
* @param pcm A PCM handle.
* @param data The audio sample array
* @param frame_count The number of frames occupied by the sample array.
* This value should not be greater than @ref TINYALSA_FRAMES_MAX
* or INT_MAX.
* @return On success, this function returns the number of frames written; otherwise, a negative number.
* @ingroup libtinyalsa-pcm
*/
static int pcm_readi(struct pcm *pcm, void *data, unsigned int frame_count)
{
struct snd_xferi x;
if (!(pcm->flags & PCM_IN))
return -EINVAL;
#if UINT_MAX > TINYALSA_FRAMES_MAX
if (frame_count > TINYALSA_FRAMES_MAX)
return -EINVAL;
#endif
if (frame_count > INT_MAX)
return -EINVAL;
x.buf = data;
x.frames = frame_count;
x.result = 0;
for (;;)
{
if ((!pcm->running) && (pcm_start(pcm) < 0))
return -errno;
else if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_READI_FRAMES, &x))
{
pcm->prepared = 0;
pcm->running = 0;
if (errno == EPIPE)
{
/* we failed to make our window -- try to restart */
pcm->underruns++;
continue;
}
RARCH_ERR("[TINYALSA]: Cannot read stream data.\n");
return -1;
}
return x.result;
}
}
/** Writes audio samples to PCM.
* If the PCM has not been started, it is started in this function.
* This function is only valid for PCMs opened with the @ref PCM_OUT flag.
* This function is not valid for PCMs opened with the @ref PCM_MMAP flag.
* @param pcm A PCM handle.
* @param data The audio sample array
* @param count The number of bytes occupied by the sample array.
* @return On success, this function returns zero; otherwise, a negative number.
* @deprecated
* @ingroup libtinyalsa-pcm
*/
static int pcm_write(struct pcm *pcm, const void *data, unsigned int count)
{
return pcm_writei(pcm, data, pcm_bytes_to_frames(pcm, count));
}
/** Reads audio samples from PCM.
* If the PCM has not been started, it is started in this function.
* This function is only valid for PCMs opened with the @ref PCM_IN flag.
* This function is not valid for PCMs opened with the @ref PCM_MMAP flag.
* @param pcm A PCM handle.
* @param data The audio sample array
* @param count The number of bytes occupied by the sample array.
* @return On success, this function returns zero; otherwise, a negative number.
* @deprecated
* @ingroup libtinyalsa-pcm
*/
static int pcm_read(struct pcm *pcm, void *data, unsigned int count)
{
return pcm_readi(pcm, data, pcm_bytes_to_frames(pcm, count));
}
#endif
static struct pcm bad_pcm = {
-1 /* fd */
};
/** Gets the hardware parameters of a PCM, without created a PCM handle.
* @param card The card of the PCM.
* The default card is zero.
* @param device The device of the PCM.
* The default device is zero.
* @param flags Specifies whether the PCM is an input or output.
* May be one of the following:
* - @ref PCM_IN
* - @ref PCM_OUT
* @return On success, the hardware parameters of the PCM; on failure, NULL.
* @ingroup libtinyalsa-pcm
*/
static struct pcm_params *pcm_params_get(unsigned int card, unsigned int device,
unsigned int flags)
{
struct snd_pcm_hw_params *params;
char fn[256];
int fd;
snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device,
flags & PCM_IN ? 'c' : 'p');
fd = open(fn, O_RDWR|O_NONBLOCK);
if (fd < 0)
{
RARCH_ERR("[TINYALSA] Cannot open device '%s'\n", fn);
goto err_open;
}
params = (struct snd_pcm_hw_params*)
calloc(1, sizeof(struct snd_pcm_hw_params));
if (!params)
goto err_calloc;
param_init(params);
if (ioctl(fd, SNDRV_PCM_IOCTL_HW_REFINE, params))
{
RARCH_ERR("[TINYALSA] SNDRV_PCM_IOCTL_HW_REFINE error (%d)\n", errno);
goto err_hw_refine;
}
close(fd);
return (struct pcm_params *)params;
err_hw_refine:
free(params);
err_calloc:
close(fd);
err_open:
return NULL;
}
/** Frees the hardware parameters returned by @ref pcm_params_get.
* @param pcm_params Hardware parameters of a PCM.
* May be NULL.
* @ingroup libtinyalsa-pcm
*/
static void pcm_params_free(struct pcm_params *pcm_params)
{
struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
if (params)
free(params);
}
#if 0
/* Unused for now */
/** Gets a mask from a PCM's hardware parameters.
* @param pcm_params A PCM's hardware parameters.
* @param param The parameter to get.
* @return If @p pcm_params is NULL or @p param is not a mask, NULL is returned.
* Otherwise, the mask associated with @p param is returned.
* @ingroup libtinyalsa-pcm
*/
static const struct pcm_mask *pcm_params_get_mask(const struct pcm_params *pcm_params,
enum pcm_param param)
{
int p;
struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
if (!params)
return NULL;
p = pcm_param_to_alsa(param);
if (p < 0 || !param_is_mask(p))
return NULL;
return (const struct pcm_mask *)param_to_mask(params, p);
}
#endif
static int pcm_param_to_alsa(enum pcm_param param)
{
switch (param)
{
case PCM_PARAM_ACCESS:
return SNDRV_PCM_HW_PARAM_ACCESS;
case PCM_PARAM_FORMAT:
return SNDRV_PCM_HW_PARAM_FORMAT;
case PCM_PARAM_SUBFORMAT:
return SNDRV_PCM_HW_PARAM_SUBFORMAT;
case PCM_PARAM_SAMPLE_BITS:
return SNDRV_PCM_HW_PARAM_SAMPLE_BITS;
case PCM_PARAM_FRAME_BITS:
return SNDRV_PCM_HW_PARAM_FRAME_BITS;
case PCM_PARAM_CHANNELS:
return SNDRV_PCM_HW_PARAM_CHANNELS;
case PCM_PARAM_RATE:
return SNDRV_PCM_HW_PARAM_RATE;
case PCM_PARAM_PERIOD_TIME:
return SNDRV_PCM_HW_PARAM_PERIOD_TIME;
case PCM_PARAM_PERIOD_SIZE:
return SNDRV_PCM_HW_PARAM_PERIOD_SIZE;
case PCM_PARAM_PERIOD_BYTES:
return SNDRV_PCM_HW_PARAM_PERIOD_BYTES;
case PCM_PARAM_PERIODS:
return SNDRV_PCM_HW_PARAM_PERIODS;
case PCM_PARAM_BUFFER_TIME:
return SNDRV_PCM_HW_PARAM_BUFFER_TIME;
case PCM_PARAM_BUFFER_SIZE:
return SNDRV_PCM_HW_PARAM_BUFFER_SIZE;
case PCM_PARAM_BUFFER_BYTES:
return SNDRV_PCM_HW_PARAM_BUFFER_BYTES;
case PCM_PARAM_TICK_TIME:
return SNDRV_PCM_HW_PARAM_TICK_TIME;
default:
break;
}
return -1;
}
static unsigned int param_get_min(const struct snd_pcm_hw_params *p, int n)
{
if (param_is_interval(n))
{
const struct snd_interval *i = param_get_interval(p, n);
return i->min;
}
return 0;
}
/** Get the minimum of a specified PCM parameter.
* @param pcm_params A PCM parameters structure.
* @param param The specified parameter to get the minimum of.
* @returns On success, the parameter minimum.
* On failure, zero.
*/
static unsigned int pcm_params_get_min(const struct pcm_params *pcm_params,
enum pcm_param param)
{
struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
int p;
if (!params)
return 0;
p = pcm_param_to_alsa(param);
if (p < 0)
return 0;
return param_get_min(params, p);
}
static unsigned int param_get_max(const struct snd_pcm_hw_params *p, int n)
{
if (param_is_interval(n))
{
const struct snd_interval *i = param_get_interval(p, n);
return i->max;
}
return 0;
}
/** Get the maximum of a specified PCM parameter.
* @param pcm_params A PCM parameters structure.
* @param param The specified parameter to get the maximum of.
* @returns On success, the parameter maximum.
* On failure, zero.
*/
static unsigned int pcm_params_get_max(const struct pcm_params *pcm_params,
enum pcm_param param)
{
const struct snd_pcm_hw_params *params = (const struct snd_pcm_hw_params *)pcm_params;
int p;
if (!params)
return 0;
p = pcm_param_to_alsa(param);
if (p < 0)
return 0;
return param_get_max(params, p);
}
/** Stops a PCM.
* @param pcm A PCM handle.
* @return On success, zero; on failure, a negative number.
* @ingroup libtinyalsa-pcm
*/
static int pcm_stop(struct pcm *pcm)
{
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DROP) < 0)
{
RARCH_ERR("[TINYALSA]: Cannot stop channel.\n");
return -1;
}
pcm->prepared = 0;
pcm->running = 0;
return 0;
}
static int pcm_params_can_pause(const struct pcm_params *pcm_params)
{
const struct snd_pcm_hw_params *params = (const struct snd_pcm_hw_params *)pcm_params;
if (!params)
return 0;
return (params->info & SNDRV_PCM_INFO_PAUSE) ? 1 : 0;
}
static int pcm_pause(struct pcm *pcm, int enable)
{
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_PAUSE, enable) < 0)
return -1;
return 0;
}
/** Closes a PCM returned by @ref pcm_open.
* @param pcm A PCM returned by @ref pcm_open.
* May not be NULL.
* @return Always returns zero.
* @ingroup libtinyalsa-pcm
*/
static int pcm_close(struct pcm *pcm)
{
if (pcm == &bad_pcm)
return 0;
pcm_hw_munmap_status(pcm);
if (pcm->flags & PCM_MMAP)
{
pcm_stop(pcm);
munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size));
}
if (pcm->fd >= 0)
close(pcm->fd);
pcm->prepared = 0;
pcm->running = 0;
pcm->buffer_size = 0;
pcm->fd = -1;
free(pcm);
return 0;
}
/** Opens a PCM.
* @param card The card that the pcm belongs to.
* The default card is zero.
* @param device The device that the pcm belongs to.
* The default device is zero.
* @param flags Specify characteristics and functionality about the pcm.
* May be a bitwise AND of the following:
* - @ref PCM_IN
* - @ref PCM_OUT
* - @ref PCM_MMAP
* - @ref PCM_NOIRQ
* - @ref PCM_MONOTONIC
* @param config The hardware and software parameters to open the PCM with.
* @returns A PCM structure.
* If an error occurs allocating memory for the PCM, NULL is returned.
* Otherwise, client code should check that the PCM opened properly by calling @ref pcm_is_ready.
* If @ref pcm_is_ready, check @ref pcm_get_error for more information.
* @ingroup libtinyalsa-pcm
*/
static struct pcm *pcm_open(unsigned int card, unsigned int device,
unsigned int flags, const struct pcm_config *config)
{
int rc;
char fn[256];
struct snd_pcm_info info;
struct pcm *pcm = (struct pcm*)calloc(1, sizeof(struct pcm));
if (!pcm)
return &bad_pcm;
snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device,
flags & PCM_IN ? 'c' : 'p');
pcm->flags = flags;
pcm->fd = open(fn, O_RDWR|O_NONBLOCK);
if (pcm->fd < 0)
{
RARCH_ERR("[TINYALSA]: cannot open device '%s'\n", fn);
return pcm;
}
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_INFO, &info))
{
RARCH_ERR("[TINYALSA]: cannot get info.\n");
goto fail_close;
}
pcm->subdevice = info.subdevice;
if (pcm_set_config(pcm, config) != 0)
goto fail_close;
rc = pcm_hw_mmap_status(pcm);
if (rc < 0)
{
RARCH_ERR("[TINYALSA]: mmap status failed.\n");
goto fail;
}
#ifdef SNDRV_PCM_IOCTL_TTSTAMP
if (pcm->flags & PCM_MONOTONIC)
{
int arg = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC;
rc = ioctl(pcm->fd, SNDRV_PCM_IOCTL_TTSTAMP, &arg);
if (rc < 0)
{
RARCH_ERR("[TINYALSA]: Cannot set timestamp type.\n");
goto fail;
}
}
#endif
pcm->underruns = 0;
return pcm;
fail:
if (flags & PCM_MMAP)
munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size));
fail_close:
close(pcm->fd);
pcm->fd = -1;
return pcm;
}
#if 0
/* Unused for now */
/** Opens a PCM by it's name.
* @param name The name of the PCM.
* The name is given in the format: <i>hw</i>:<b>card</b>,<b>device</b>
* @param flags Specify characteristics and functionality about the pcm.
* May be a bitwise AND of the following:
* - @ref PCM_IN
* - @ref PCM_OUT
* - @ref PCM_MMAP
* - @ref PCM_NOIRQ
* - @ref PCM_MONOTONIC
* @param config The hardware and software parameters to open the PCM with.
* @returns A PCM structure.
* If an error occurs allocating memory for the PCM, NULL is returned.
* Otherwise, client code should check that the PCM opened properly by calling @ref pcm_is_ready.
* If @ref pcm_is_ready, check @ref pcm_get_error for more information.
* @ingroup libtinyalsa-pcm
*/
static struct pcm *pcm_open_by_name(const char *name,
unsigned int flags,
const struct pcm_config *config)
{
unsigned int card, device;
if ((name[0] != 'h')
|| (name[1] != 'w')
|| (name[2] != ':'))
return NULL;
if (sscanf(&name[3], "%u,%u", &card, &device) != 2)
return NULL;
return pcm_open(card, device, flags, config);
}
/** Links two PCMs.
* After this function is called, the two PCMs will prepare, start and stop in sync (at the same time).
* If an error occurs, the error message will be written to @p pcm1.
* @param pcm1 A PCM handle.
* @param pcm2 Another PCM handle.
* @return On success, zero; on failure, a negative number.
* @ingroup libtinyalsa-pcm
*/
static int pcm_link(struct pcm *pcm1, struct pcm *pcm2)
{
int err = ioctl(pcm1->fd, SNDRV_PCM_IOCTL_LINK, pcm2->fd);
if (err == -1)
{
RARCH_ERR("[TINYALSA]: Cannot link PCM.\n");
return -1;
}
return 0;
}
/** Unlinks a PCM.
* @see @ref pcm_link
* @param pcm A PCM handle.
* @return On success, zero; on failure, a negative number.
* @ingroup libtinyalsa-pcm
*/
static int pcm_unlink(struct pcm *pcm)
{
int err = ioctl(pcm->fd, SNDRV_PCM_IOCTL_UNLINK);
if (err == -1)
{
RARCH_ERR("[TINYALSA]: Cannot unlink PCM.\n");
return -1;
}
return 0;
}
#endif
static int pcm_avail_update(struct pcm *pcm)
{
pcm_sync_ptr(pcm, 0);
return pcm_mmap_avail(pcm);
}
#if 0
/* No longer used */
static int pcm_state(struct pcm *pcm)
{
int err = pcm_sync_ptr(pcm, 0);
if (err < 0)
return err;
return pcm->mmap_status->state;
}
#endif
/** Waits for frames to be available for read or write operations.
* @param pcm A PCM handle.
* @param timeout The maximum amount of time to wait for, in terms of milliseconds.
* @returns If frames became available, one is returned.
* If a timeout occurred, zero is returned.
* If an error occurred, a negative number is returned.
* @ingroup libtinyalsa-pcm
*/
static int pcm_wait(struct pcm *pcm, int timeout)
{
struct pollfd pfd;
pfd.fd = pcm->fd;
pfd.events = POLLIN | POLLOUT | POLLERR | POLLNVAL;
do
{
/* let's wait for avail or timeout */
int err = poll(&pfd, 1, timeout);
if (err < 0)
return -errno;
/* timeout ? */
if (err == 0)
return 0;
/* have we been interrupted ? */
if (errno == -EINTR)
continue;
/* check for any errors */
if (pfd.revents & (POLLERR | POLLNVAL))
{
int cond = -1;
if (pcm->sync_ptr)
{
pcm->sync_ptr->flags = 0;
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SYNC_PTR, pcm->sync_ptr) >= 0)
cond = pcm->mmap_status->state;
}
switch (cond)
{
case PCM_STATE_XRUN:
return -EPIPE;
case PCM_STATE_SUSPENDED:
return -ESTRPIPE;
case PCM_STATE_DISCONNECTED:
return -ENODEV;
default:
break;
}
return -EIO;
}
/* poll again if fd not ready for IO */
} while (!(pfd.revents & (POLLIN | POLLOUT)));
return 1;
}
#if 0
/* Unused for now */
static int pcm_mmap_transfer(struct pcm *pcm, const void *buffer, unsigned int bytes)
{
int err = 0, frames, avail;
unsigned int offset = 0, count;
if (bytes == 0)
return 0;
count = pcm_bytes_to_frames(pcm, bytes);
while (count > 0)
{
/* get the available space for writing new frames */
avail = pcm_avail_update(pcm);
if (avail < 0)
{
RARCH_ERR("[TINYALSA] Cannot determine available mmap frames");
return err;
}
/* start the audio if we reach the threshold */
if (!pcm->running &&
(pcm->buffer_size - avail) >= pcm->config.start_threshold)
{
if (pcm_start(pcm) < 0)
{
RARCH_ERR("[TINYALSA] Start error: hw 0x%x app 0x%x avail 0x%x\n",
(unsigned int)pcm->mmap_status->hw_ptr,
(unsigned int)pcm->mmap_control->appl_ptr,
avail);
return -errno;
}
}
/* sleep until we have space to write new frames */
if (pcm->running &&
(unsigned int)avail < pcm->mmap_control->avail_min)
{
int time = -1;
if (pcm->flags & PCM_NOIRQ)
time = (pcm->buffer_size - avail - pcm->mmap_control->avail_min)
/ pcm->noirq_frames_per_msec;
err = pcm_wait(pcm, time);
if (err < 0)
{
pcm->prepared = 0;
pcm->running = 0;
RARCH_ERR("[TINYALSA] Wait error: hw 0x%x app 0x%x avail 0x%x\n",
(unsigned int)pcm->mmap_status->hw_ptr,
(unsigned int)pcm->mmap_control->appl_ptr,
avail);
pcm->mmap_control->appl_ptr = 0;
return err;
}
continue;
}
frames = count;
if (frames > avail)
frames = avail;
if (!frames)
break;
/* copy frames from buffer */
frames = pcm_mmap_transfer_areas(pcm, (void *)buffer, offset, frames);
if (frames < 0)
{
RARCH_ERR("[TINYALSA] Write error: hw 0x%x app 0x%x avail 0x%x\n",
(unsigned int)pcm->mmap_status->hw_ptr,
(unsigned int)pcm->mmap_control->appl_ptr,
avail);
return frames;
}
offset += frames;
count -= frames;
}
return 0;
}
static int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count)
{
if ((~pcm->flags) & (PCM_OUT | PCM_MMAP))
return -ENOSYS;
return pcm_mmap_transfer(pcm, (void *)data, count);
}
static int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count)
{
if ((~pcm->flags) & (PCM_IN | PCM_MMAP))
return -ENOSYS;
return pcm_mmap_transfer(pcm, data, count);
}
/** Gets the delay of the PCM, in terms of frames.
* @param pcm A PCM handle.
* @returns On success, the delay of the PCM.
* On failure, a negative number.
* @ingroup libtinyalsa-pcm
*/
static long pcm_get_delay(struct pcm *pcm)
{
if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DELAY, &pcm->pcm_delay) < 0)
return -1;
return pcm->pcm_delay;
}
static int pcm_mmap_transfer_areas(struct pcm *pcm, char *buf,
unsigned int offset, unsigned int size)
{
void *pcm_areas;
int commit;
unsigned int pcm_offset, frames, count = 0;
while (size > 0)
{
frames = size;
pcm_mmap_begin(pcm, &pcm_areas, &pcm_offset, &frames);
pcm_areas_copy(pcm, pcm_offset, buf, offset, frames);
commit = pcm_mmap_commit(pcm, pcm_offset, frames);
if (commit < 0)
{
RARCH_ERR("[TINYALSA}: failed to commit %d frames.\n", frames);
return commit;
}
offset += commit;
count += commit;
size -= commit;
}
return count;
}
#endif
/* End of implementation tinyalsa pcm */
typedef struct tinyalsa
{
struct pcm *pcm;
struct pcm_params *params;
size_t buffer_size;
bool nonblock;
bool has_float;
bool can_pause;
bool is_paused;
unsigned int frame_bits;
} tinyalsa_t;
#define BYTES_TO_FRAMES(bytes, frame_bits) ((bytes) * 8 / frame_bits)
#define FRAMES_TO_BYTES(frames, frame_bits) ((frames) * frame_bits / 8)
static void * tinyalsa_init(const char *devicestr, unsigned rate,
unsigned latency, unsigned block_frames,
unsigned *new_rate)
{
unsigned int card = 0;
unsigned int device = 0;
unsigned int frames_per_ms = 0;
unsigned int orig_rate = rate;
unsigned int max_rate, min_rate, buffer_size;
float initial_latency;
struct pcm_config config;
tinyalsa_t *tinyalsa = (tinyalsa_t*)calloc(1, sizeof(tinyalsa_t));
if (!tinyalsa)
return NULL;
if (devicestr)
sscanf(devicestr, "%u,%u", &card, &device);
RARCH_LOG("[TINYALSA]: Using card: %u, device: %u.\n", card, device);
tinyalsa->params = pcm_params_get(card, device, PCM_OUT);
if (!tinyalsa->params)
{
RARCH_ERR("[TINYALSA]: params: Cannot open audio device.\n");
goto error;
}
if (pcm_params_can_pause(tinyalsa->params))
tinyalsa->can_pause = true;
min_rate = pcm_params_get_min(tinyalsa->params, PCM_PARAM_RATE);
max_rate = pcm_params_get_max(tinyalsa->params, PCM_PARAM_RATE);
if (!(rate >= min_rate && rate <= max_rate))
{
RARCH_WARN("[TINYALSA]: Sample rate cannot be larger than %uHz "\
"or smaller than %uHz.\n", max_rate, min_rate);
RARCH_WARN("[TINYALSA]: Trying to set a valid sample rate.\n");
if (rate > max_rate)
rate = max_rate;
else if (rate < min_rate)
rate = min_rate;
}
if (orig_rate != rate)
*new_rate = rate;
config.rate = rate;
config.format = is_little_endian() ?\
PCM_FORMAT_S16_LE : PCM_FORMAT_S16_BE;
config.channels = 2;
config.period_size = 1024;
config.period_count = 4;
config.start_threshold = config.period_size;
config.stop_threshold = 0;
config.silence_threshold = 0;
tinyalsa->pcm = pcm_open(card, device, PCM_OUT, &config);
if (!tinyalsa->pcm)
{
RARCH_ERR("[TINYALSA]: Failed to allocate memory for pcm.\n");
goto error;
}
else if (!pcm_is_ready(tinyalsa->pcm))
{
RARCH_ERR("[TINYALSA]: Cannot open audio device.\n");
goto error;
}
buffer_size = pcm_get_buffer_size(tinyalsa->pcm);
tinyalsa->buffer_size = pcm_frames_to_bytes(tinyalsa->pcm, buffer_size);
tinyalsa->frame_bits = pcm_format_to_bits(config.format) * 2;
initial_latency = (float)(buffer_size * 1000) / (float)(rate * 4);
frames_per_ms = buffer_size / initial_latency;
if (latency < (unsigned int)initial_latency)
{
RARCH_WARN("[TINYALSA]: Cannot have a latency less than %ums. "\
"Defaulting to 64ms.\n", (unsigned int)initial_latency);
latency = 64;
}
latency -= (unsigned int)initial_latency;
buffer_size += latency * frames_per_ms;
tinyalsa->has_float = false;
RARCH_LOG("[TINYALSA]: Can pause: %s.\n", tinyalsa->can_pause ? "yes" : "no");
RARCH_LOG("[TINYALSA]: Audio rate: %uHz.\n", config.rate);
RARCH_LOG("[TINYALSA]: Buffer size: %u frames.\n", buffer_size);
RARCH_LOG("[TINYALSA]: Buffer size: %u bytes.\n", (unsigned int)tinyalsa->buffer_size);
RARCH_LOG("[TINYALSA]: Frame size: %u bytes.\n", tinyalsa->frame_bits / 8);
RARCH_LOG("[TINYALSA]: Latency: %ums.\n", buffer_size * 1000 / (rate * 4));
pcm_params_free(tinyalsa->params);
return tinyalsa;
error:
RARCH_ERR("[TINYALSA]: Failed to initialize tinyalsa driver.\n");
if (tinyalsa->params)
pcm_params_free(tinyalsa->params);
if (tinyalsa)
free(tinyalsa);
return NULL;
}
static ssize_t
tinyalsa_write(void *data, const void *buf_, size_t size_)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
const uint8_t *buf = (const uint8_t*)buf_;
snd_pcm_sframes_t written = 0;
snd_pcm_sframes_t size = BYTES_TO_FRAMES(size_, tinyalsa->frame_bits);
size_t frames_size = tinyalsa->has_float ? sizeof(float) : sizeof(int16_t);
if (tinyalsa->nonblock)
{
while (size)
{
snd_pcm_sframes_t frames = pcm_writei(tinyalsa->pcm, buf, size);
if (frames < 0)
pcm_stop(tinyalsa->pcm);
written += frames;
buf += (frames << 1) * frames_size;
size -= frames;
}
}
else
{
while (size)
{
snd_pcm_sframes_t frames;
pcm_wait(tinyalsa->pcm, -1);
frames = pcm_writei(tinyalsa->pcm, buf, size);
if (frames < 0)
return -1;
written += frames;
buf += (frames << 1) * frames_size;
size -= frames;
}
}
return written;
}
static bool
tinyalsa_stop(void *data)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
if (tinyalsa->can_pause && !tinyalsa->is_paused)
{
int ret = pcm_pause(tinyalsa->pcm, 1);
if (ret < 0)
return false;
tinyalsa->is_paused = true;
}
return true;
}
static bool
tinyalsa_alive(void *data)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
if (tinyalsa)
return !tinyalsa->is_paused;
return false;
}
static bool
tinyalsa_start(void *data, bool is_shutdown)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
if (tinyalsa->can_pause && tinyalsa->is_paused)
{
int ret = pcm_pause(tinyalsa->pcm, 0);
if (ret < 0)
{
RARCH_ERR("[TINYALSA]: Failed to unpause.\n");
return false;
}
tinyalsa->is_paused = false;
}
return true;
}
static void tinyalsa_set_nonblock_state(void *data, bool state)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
tinyalsa->nonblock = state;
}
static bool tinyalsa_use_float(void *data)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
return tinyalsa->has_float;
}
static void tinyalsa_free(void *data)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
if (tinyalsa)
{
if (tinyalsa->pcm)
pcm_close(tinyalsa->pcm);
tinyalsa->pcm = NULL;
free(tinyalsa);
}
}
static size_t tinyalsa_write_avail(void *data)
{
tinyalsa_t *alsa = (tinyalsa_t*)data;
snd_pcm_sframes_t avail = pcm_avail_update(alsa->pcm);
if (avail < 0)
return alsa->buffer_size;
return FRAMES_TO_BYTES(avail, alsa->frame_bits);
}
static size_t tinyalsa_buffer_size(void *data)
{
tinyalsa_t *tinyalsa = (tinyalsa_t*)data;
return tinyalsa->buffer_size;
}
audio_driver_t audio_tinyalsa = {
tinyalsa_init, /* AUDIO_init */
tinyalsa_write, /* AUDIO_write */
tinyalsa_stop, /* AUDIO_stop */
tinyalsa_start, /* AUDIO_start */
tinyalsa_alive, /* AUDIO_alive */
tinyalsa_set_nonblock_state, /* AUDIO_set_nonblock_sate */
tinyalsa_free, /* AUDIO_free */
tinyalsa_use_float, /* AUDIO_use_float */
"tinyalsa", /* "AUDIO" */
NULL, /* AUDIO_device_list_new */ /*TODO*/
NULL, /* AUDIO_device_list_free */ /*TODO*/
tinyalsa_write_avail, /* AUDIO_write_avail */ /*TODO*/
tinyalsa_buffer_size, /* AUDIO_buffer_size */ /*TODO*/
};