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/*
* Copyright 2023 jacqueline <me@jacqueline.id.au>
*
* SPDX-License-Identifier: GPL-3.0-only
*/
#include "digital_pot.hpp"
#include <cstdint>
namespace drivers {
using GpioExpander::VOL_LEFT;
using GpioExpander::VOL_RIGHT;
using GpioExpander::VOL_UP_DOWN;
using GpioExpander::VOL_Z_CROSS;
DigitalPot::DigitalPot(GpioExpander* gpios) : gpios_(gpios) {
gpios_->set_pin(VOL_Z_CROSS, true); // Active-low
gpios_->set_pin(VOL_UP_DOWN, true);
gpios_->set_pin(VOL_LEFT, false);
gpios_->set_pin(VOL_RIGHT, false);
gpios_->Write();
// Power-on reset sets attenuation to maximum anyway, but we want to be safe
// and not blow anyone's ears out.
for (int i = 0; i < 32; i++) {
gpios_->set_pin(VOL_LEFT, true);
gpios_->set_pin(VOL_RIGHT, true);
gpios_->Write();
gpios_->set_pin(VOL_LEFT, false);
gpios_->set_pin(VOL_RIGHT, false);
gpios_->Write();
}
}
auto DigitalPot::SetRelative(int_fast8_t change) -> void {
if (change == 0) {
return;
}
gpios_->set_pin(VOL_UP_DOWN, change > 0);
gpios_->Write();
for (int i = 0; i < std::abs(change); i++) {
gpios_->set_pin(VOL_LEFT, true);
gpios_->set_pin(VOL_RIGHT, true);
gpios_->Write();
gpios_->set_pin(VOL_LEFT, false);
gpios_->set_pin(VOL_RIGHT, false);
gpios_->Write();
}
}
auto DigitalPot::SetRelative(Channel ch, int_fast8_t change) -> void {
if (change == 0) {
return;
}
GpioExpander::Pin pin = (ch == Channel::kLeft) ? VOL_LEFT : VOL_RIGHT;
gpios_->set_pin(VOL_UP_DOWN, change > 0);
gpios_->Write();
for (int i = 0; i < std::abs(change); i++) {
gpios_->set_pin(pin, true);
gpios_->Write();
gpios_->set_pin(pin, false);
gpios_->Write();
}
}
auto DigitalPot::SetZeroCrossDetect(bool enabled) -> void {
gpios_->set_pin(VOL_Z_CROSS, !enabled); // Active-low
gpios_->Write();
}
auto DigitalPot::GetMaxAttenuation() -> int_fast8_t {
return 31;
}
auto DigitalPot::GetMinAttenuation() -> int_fast8_t {
return 0;
}
} // namespace drivers
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