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/*
* Copyright 2023 jacqueline <me@jacqueline.id.au>
*
* SPDX-License-Identifier: GPL-3.0-only
*/
#include "drivers/wm8523.hpp"
#include <stdint.h>
#include <cstdint>
#include "driver/i2c_master.h"
#include "driver/i2c_types.h"
#include "esp_err.h"
#include "drivers/i2c.hpp"
#include "hal/i2c_types.h"
namespace drivers {
namespace wm8523 {
const uint16_t kAbsoluteMaxVolume = 0x1ff;
const uint16_t kAbsoluteMinVolume = 0b0;
// This is 3dB below what the DAC considers to be '0dB', and 9.5dB above line
// level reference.
const uint16_t kMaxVolumeBeforeClipping = 0x184;
// This is 12.5 dB below what the DAC considers to be '0dB'.
const uint16_t kLineLevelReferenceVolume = 0x15E;
// Default to -24 dB, which I will claim is 'arbitrarily chosen to be safe but
// audible', but is in fact just a nice value for my headphones in particular.
const uint16_t kDefaultVolume = kLineLevelReferenceVolume - 96;
// Default to +6dB == 2Vrms == 'CD Player'
const uint16_t kDefaultMaxVolume = kLineLevelReferenceVolume + 12;
const uint16_t kZeroDbVolume = 0x190;
static const uint8_t kAddress = 0b0011010;
static i2c_master_dev_handle_t sI2C;
auto Init() -> esp_err_t {
i2c_device_config_t config = {
.dev_addr_length = I2C_ADDR_BIT_LEN_7,
.device_address = kAddress,
.scl_speed_hz = 400'000,
.scl_wait_us = 0,
.flags = {.disable_ack_check = false},
};
return i2c_master_bus_add_device(i2c_handle(), &config, &sI2C);
}
auto ReadRegister(Register reg) -> std::optional<uint16_t> {
uint8_t cmd[] = {static_cast<uint8_t>(reg)};
uint8_t data[] = {0, 0};
if (i2c_master_transmit_receive(sI2C, cmd, 1, data, 2, 100) != ESP_OK) {
return {};
}
return (data[0] << 8) | data[1];
}
auto WriteRegister(Register reg, uint16_t data) -> bool {
return WriteRegister(reg, (data >> 8) & 0xFF, data & 0xFF);
}
auto WriteRegister(Register reg, uint8_t msb, uint8_t lsb) -> bool {
uint8_t cmd[] = {static_cast<uint8_t>(reg), msb, lsb};
return i2c_master_transmit(sI2C, cmd, 3, 100) == ESP_OK;
}
} // namespace wm8523
} // namespace drivers
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