rockbox/firmware/export/ak4376.h
Aidan MacDonald c1f1d91404 FiiO M3K: audio recording
Recording works now, although I'm sure there will be a few
things that need fine-tuning. A major issue is that writing
to the SD card creates noticable interference, which happens
on the original firmware too but seems worse under Rockbox.

(Since Rockbox waits until RAM fills up before writing data,
the interference will only be heard on >50 MiB recordings.)

Change-Id: I5561dd9668c3bdd34e92f34ef50848aef8c0b7eb
2022-01-29 19:28:03 +00:00

154 lines
5.2 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2021 Aidan MacDonald
*
* This program 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 Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef __AK4376_H__
#define __AK4376_H__
/* The target config must define this; defining it here would prevent
the target from supporting audio recording via an alternate codec. */
/* #define AUDIOHW_CAPS (FILTER_ROLL_OFF_CAP|POWER_MODE_CAP) */
#define AUDIOHW_HAVE_SHORT2_ROLL_OFF
#define AK4376_MIN_VOLUME (-890)
#define AK4376_MAX_VOLUME 150
AUDIOHW_SETTING(VOLUME, "dB", 1, 5, AK4376_MIN_VOLUME, AK4376_MAX_VOLUME, -200)
AUDIOHW_SETTING(FILTER_ROLL_OFF, "", 0, 1, 0, 3, 0)
AUDIOHW_SETTING(POWER_MODE, "", 0, 1, 0, 1, 0)
/* Register addresses */
#define AK4376_REG_PWR1 0x00
#define AK4376_REG_PWR2 0x01
#define AK4376_REG_PWR3 0x02
#define AK4376_REG_PWR4 0x03
#define AK4376_REG_OUTPUT_MODE 0x04
#define AK4376_REG_CLOCK_MODE 0x05
#define AK4376_REG_FILTER 0x06
#define AK4376_REG_MIXER 0x07
#define AK4376_REG_LCH_VOLUME 0x0b
#define AK4376_REG_RCH_VOLUME 0x0c
#define AK4376_REG_AMP_VOLUME 0x0d
#define AK4376_REG_PLL_CLK_SRC 0x0e
#define AK4376_REG_PLL_REF_DIV1 0x0f
#define AK4376_REG_PLL_REF_DIV2 0x10
#define AK4376_REG_PLL_FB_DIV1 0x11
#define AK4376_REG_PLL_FB_DIV2 0x12
#define AK4376_REG_DAC_CLK_SRC 0x13
#define AK4376_REG_DAC_CLK_DIV 0x14
#define AK4376_REG_AUDIO_IF_FMT 0x15
#define AK4376_REG_CHIP_ID 0x21
#define AK4376_REG_MODE_CTRL 0x24
#define AK4376_REG_ADJUST1 0x26
#define AK4376_REG_ADJUST2 0x2a
#define AK4376_NUM_REGS 0x2b
/* Mixer controls, simply OR them together.
* LCH = add LCH signal to output
* RCH = add RCH signal to output
* HALF = multiply output by 1/2
* INVERT = invert the output after everything else
*/
#define AK4376_MIX_MUTE 0
#define AK4376_MIX_LCH 1
#define AK4376_MIX_RCH 2
#define AK4376_MIX_HALF 4
#define AK4376_MIX_INVERT 8
/* Min/max digital volumes in units of dB/10 */
#define AK4376_DIG_VOLUME_MIN (-120)
#define AK4376_DIG_VOLUME_MAX 30
#define AK4376_DIG_VOLUME_STEP 5
#define AK4376_DIG_VOLUME_MUTE (AK4376_DIG_VOLUME_MIN - 1)
/* Min/max headphone amp volumes in units of dB/10 */
#define AK4376_AMP_VOLUME_MIN (-200)
#define AK4376_AMP_VOLUME_MAX 60
#define AK4376_AMP_VOLUME_STEP 20
#define AK4376_AMP_VOLUME_MUTE (AK4376_AMP_VOLUME_MIN - 1)
/* Digital filters */
#define AK4376_FILTER_SHARP 0
#define AK4376_FILTER_SLOW 1
#define AK4376_FILTER_SHORT_SHARP 2
#define AK4376_FILTER_SHORT_SLOW 3
/* Frequency selection */
#define AK4376_FS_8 0
#define AK4376_FS_11 1
#define AK4376_FS_12 2
#define AK4376_FS_16 4
#define AK4376_FS_22 5
#define AK4376_FS_24 6
#define AK4376_FS_32 8
#define AK4376_FS_44 9
#define AK4376_FS_48 10
#define AK4376_FS_64 12
#define AK4376_FS_88 13
#define AK4376_FS_96 14
#define AK4376_FS_176 17
#define AK4376_FS_192 18
/* Functions to power on / off the DAC.
*
* NOTE: Target must call ak4376_set_frequency() after ak4376_open() to
* finish the power-up sequence of the headphone amp.
*/
extern void ak4376_open(void);
extern void ak4376_close(void);
/* Register read/write. Cached to avoid redundant reads/writes. */
extern void ak4376_write(int reg, int value);
extern int ak4376_read(int reg);
/* Target-specific function to set the PDN pin level. */
extern void ak4376_set_pdn_pin(int level);
/* Set overall output volume */
extern void ak4376_set_volume(int vol_l, int vol_r);
/* Set the roll-off filter */
extern void ak4376_set_filter_roll_off(int val);
/* Set audio sampling frequency and power mode.
*
* If the I2S master clock is being supplied externally, the caller must also
* give the master clock multiplier 'mult'. The accepted values depend on the
* sampling rate, see below:
*
* +-----------+------------------------+
* | frequency | master clock rate |
* +-----------+------------------------+
* | 8 - 24 | 256fs / 512fs / 1024fs |
* | 32 - 48 | 256fs / 512fs |
* | 64 - 96 | 256fs |
* | 128 - 192 | 128fs |
* +-----------+------------------------+
*
* Switching between high-power and low-power mode requires the same registers
* and power-up / power-down sequences as a frequency switch, so both settings
* are controlled by this function.
*
* high power mode -- use power_mode=SOUND_HIGH_POWER
* low power mode -- use power_mode=SOUND_LOW_POWER
*/
extern void ak4376_set_freqmode(int fsel, int mult, int power_mode);
#endif /* __AK4376_H__ */