rockbox/firmware/drivers/audio/ak4376.c
Aidan MacDonald 3ec66893e3 New port: FiiO M3K on bare metal
Change-Id: I7517e7d5459e129dcfc9465c6fbd708619888fbe
2021-03-28 00:01:37 +00:00

274 lines
8.2 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.
*
****************************************************************************/
#include "audiohw.h"
#include "sound.h"
#include "panic.h"
#include "pcm_sampr.h"
#include "pcm_sw_volume.h"
#include "system.h"
#include "i2c-async.h"
#ifndef HAVE_SW_VOLUME_CONTROL
# error "AK4376 requires HAVE_SW_VOLUME_CONTROL!"
#endif
/* NOTE: At present, only the FiiO M3K uses this driver so the handling of
* the clock / audio interface is limited to I2S slave, 16-bit samples, with
* DAC master clock provided directly on the MCLK input pin, fitting the
* clock setup of the M3K.
*
* Feel free to expand upon this if another target ever needs this driver.
*/
/* Converts HW_FREQ_XX constants to register values */
static const int ak4376_fsel_to_hw[] = {
HW_HAVE_192_(AK4376_FS_192,)
HW_HAVE_176_(AK4376_FS_176,)
HW_HAVE_96_(AK4376_FS_96,)
HW_HAVE_88_(AK4376_FS_88,)
HW_HAVE_64_(AK4376_FS_64,)
HW_HAVE_48_(AK4376_FS_48,)
HW_HAVE_44_(AK4376_FS_44,)
HW_HAVE_32_(AK4376_FS_32,)
HW_HAVE_24_(AK4376_FS_24,)
HW_HAVE_22_(AK4376_FS_22,)
HW_HAVE_16_(AK4376_FS_16,)
HW_HAVE_12_(AK4376_FS_12,)
HW_HAVE_11_(AK4376_FS_11,)
HW_HAVE_8_(AK4376_FS_8,)
};
static struct ak4376 {
int fsel;
int low_mode;
int regs[AK4376_NUM_REGS];
} ak4376;
void ak4376_init(void)
{
/* Initialize DAC state */
ak4376.fsel = HW_FREQ_48;
ak4376.low_mode = 0;
for(int i = 0; i < AK4376_NUM_REGS; ++i)
ak4376.regs[i] = -1;
/* Initial reset after power-on */
ak4376_set_pdn_pin(0);
mdelay(1);
ak4376_set_pdn_pin(1);
mdelay(1);
static const int init_config[] = {
/* Ensure HPRHZ, HPLHZ are 0 */
AK4376_REG_OUTPUT_MODE, 0x00,
/* Mute all volume controls */
AK4376_REG_MIXER, 0x00,
AK4376_REG_LCH_VOLUME, 0x80,
AK4376_REG_RCH_VOLUME, 0x00,
AK4376_REG_AMP_VOLUME, 0x00,
/* Clock source = MCLK, divider = 1 */
AK4376_REG_DAC_CLK_SRC, 0x00,
AK4376_REG_DAC_CLK_DIV, 0x00,
/* I2S slave mode, 16-bit samples */
AK4376_REG_AUDIO_IF_FMT, 0x03,
/* Recommended by datasheet */
AK4376_REG_ADJUST1, 0x20,
AK4376_REG_ADJUST2, 0x05,
/* Power controls */
AK4376_REG_PWR2, 0x33,
AK4376_REG_PWR3, 0x01,
AK4376_REG_PWR4, 0x03,
};
/* Write initial configuration prior to power-up */
for(size_t i = 0; i < ARRAYLEN(init_config); i += 2)
ak4376_write(init_config[i], init_config[i+1]);
/* Initial frequency setting, also handles DAC/amp power-up */
audiohw_set_frequency(HW_FREQ_48);
}
void ak4376_close(void)
{
/* Shut off power */
ak4376_write(AK4376_REG_PWR3, 0x00);
ak4376_write(AK4376_REG_PWR4, 0x00);
ak4376_write(AK4376_REG_PWR2, 0x00);
/* PDN pin low */
ak4376_set_pdn_pin(0);
}
void ak4376_write(int reg, int value)
{
/* Ensure value is sensible and differs from the last set value */
if((value & 0xff) == value && ak4376.regs[reg] != value) {
int r = i2c_reg_write1(AK4376_BUS, AK4376_ADDR, reg, value);
if(r == I2C_STATUS_OK)
ak4376.regs[reg] = value;
else
ak4376.regs[reg] = -1;
}
}
int ak4376_read(int reg)
{
/* Only read from I2C if we don't already know the value */
if(ak4376.regs[reg] < 0)
ak4376.regs[reg] = i2c_reg_read1(AK4376_BUS, AK4376_ADDR, reg);
return ak4376.regs[reg];
}
static int round_step_up(int x, int step)
{
int rem = x % step;
if(rem > 0)
rem -= step;
return x - rem;
}
static void calc_volumes(int vol, int* mix, int* dig, int* sw)
{
/* Mixer can divide by 2, which gives an extra -6 dB adjustment */
if(vol < AK4376_DIG_VOLUME_MIN) {
*mix |= AK4376_MIX_HALF;
vol += 60;
}
*dig = round_step_up(vol, AK4376_DIG_VOLUME_STEP);
*dig = MIN(*dig, AK4376_DIG_VOLUME_MAX);
*dig = MAX(*dig, AK4376_DIG_VOLUME_MIN);
vol -= *dig;
/* Seems that this is the allowable range for software volume */
*sw = MIN(vol, 60);
*sw = MAX(*sw, -730);
vol -= *sw;
}
static int dig_vol_to_hw(int vol)
{
if(vol < AK4376_DIG_VOLUME_MIN) return 0;
if(vol > AK4376_DIG_VOLUME_MAX) return 31;
return (vol - AK4376_DIG_VOLUME_MIN) / AK4376_DIG_VOLUME_STEP + 1;
}
static int amp_vol_to_hw(int vol)
{
if(vol < AK4376_AMP_VOLUME_MIN) return 0;
if(vol > AK4376_AMP_VOLUME_MAX) return 14;
return (vol - AK4376_AMP_VOLUME_MIN) / AK4376_AMP_VOLUME_STEP + 1;
}
void audiohw_set_volume(int vol_l, int vol_r)
{
int amp;
int mix_l = AK4376_MIX_LCH, dig_l, sw_l;
int mix_r = AK4376_MIX_RCH, dig_r, sw_r;
if(vol_l <= AK4376_MIN_VOLUME && vol_r <= AK4376_MIN_VOLUME) {
/* Special case for full mute */
amp = AK4376_AMP_VOLUME_MUTE;
dig_l = dig_r = AK4376_DIG_VOLUME_MUTE;
sw_l = sw_r = PCM_MUTE_LEVEL;
} else {
/* Amp is a mono control -- calculate based on the loudest channel.
* The quieter channel then gets reduced more by digital controls. */
amp = round_step_up(MAX(vol_l, vol_r), AK4376_AMP_VOLUME_STEP);
amp = MIN(amp, AK4376_AMP_VOLUME_MAX);
amp = MAX(amp, AK4376_AMP_VOLUME_MIN);
/* Other controls are stereo */
calc_volumes(vol_l - amp, &mix_l, &dig_l, &sw_l);
calc_volumes(vol_r - amp, &mix_r, &dig_r, &sw_r);
}
ak4376_write(AK4376_REG_MIXER, (mix_l & 0xf) | ((mix_r & 0xf) << 4));
ak4376_write(AK4376_REG_LCH_VOLUME, dig_vol_to_hw(dig_l) | (1 << 7));
ak4376_write(AK4376_REG_RCH_VOLUME, dig_vol_to_hw(dig_r));
ak4376_write(AK4376_REG_AMP_VOLUME, amp_vol_to_hw(amp));
pcm_set_master_volume(sw_l, sw_r);
}
void audiohw_set_filter_roll_off(int val)
{
int reg = ak4376_read(AK4376_REG_FILTER);
reg &= ~0xc0;
reg |= (val & 3) << 6;
ak4376_write(AK4376_REG_FILTER, reg);
}
void audiohw_set_frequency(int fsel)
{
/* Determine master clock multiplier */
int mult = ak4376_set_mclk_freq(fsel, false);
/* Calculate clock mode for frequency. Multipliers of 32/64 are only
* for rates >= 256 KHz which are not supported by Rockbox, so they
* are commented out -- but they're in the correct place. */
int clock_mode = ak4376_fsel_to_hw[fsel];
switch(mult) {
/* case 32: */
case 256:
break;
/* case 64: */
case 512:
clock_mode |= 0x20;
break;
case 1024:
clock_mode |= 0x40;
break;
case 128:
clock_mode |= 0x60;
break;
default:
panicf("ak4376: bad master clock multiple %d", mult);
return;
}
/* Handle the DSMLP bit in the MODE_CTRL register */
int mode_ctrl = 0x00;
if(ak4376.low_mode || hw_freq_sampr[fsel] <= SAMPR_12)
mode_ctrl |= 0x40;
/* Program the new settings */
ak4376_write(AK4376_REG_CLOCK_MODE, clock_mode);
ak4376_write(AK4376_REG_MODE_CTRL, mode_ctrl);
ak4376_write(AK4376_REG_PWR3, ak4376.low_mode ? 0x11 : 0x01);
/* Enable the master clock */
ak4376_set_mclk_freq(fsel, true);
/* Remember the frequency */
ak4376.fsel = fsel;
}
void audiohw_set_power_mode(int mode)
{
/* This is handled via audiohw_set_frequency() since changing LPMODE
* bit requires power-down/power-up & changing other bits as well */
if(ak4376.low_mode != mode) {
ak4376.low_mode = mode;
audiohw_set_frequency(ak4376.fsel);
}
}