dac.hpp

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#pragma once
 
#include <cpp/common/frontend/dac.hpp>
 
#include <cmath>
 
namespace bsp::mid::drv {
 
    template<auto Context, u8 Index, u32 Offset, u32 MaxValue>
    struct DACChannel {
        DACChannel(const DACChannel&) = delete;
        auto operator=(const DACChannel&) = delete;
 
        constexpr static auto ReferenceVoltage = 3.3;
 
        static bool init() {
            DACChannel::s_device = open(("/sys/bus/iio/devices/iio:device" + std::to_string(Context) + "/out_voltage" + std::to_string(Index) + "_raw").c_str(), O_RDWR);
            return DACChannel::s_device != -1;
        }
 
        static bool deinit() {
            close(DACChannel::s_device);
            return true;
        }
 
        auto operator=(float value) const noexcept {
            u32 rawValue = std::max<float>(value * MaxValue - Offset, 0.0F);
 
            std::string data = std::to_string(rawValue);
            lseek(DACChannel::s_device, 0, 0);
            if (write(DACChannel::s_device, data.data(), data.size()) <= 0)
                return;
            lseek(DACChannel::s_device, 0, 0);
        }
 
        operator float() const noexcept {
            std::string data(0xFF, 0x00);
 
            if (read(DACChannel::s_device, data.data(), data.size()) < 0)
                return 0.0F;
            lseek(DACChannel::s_device, 0, 0);
 
            return float(std::max<float>(std::stof(data) + Offset, 0)) / MaxValue;
        }
 
    private:
        DACChannel() = default;
 
        template<auto, template<auto, u8, u32, u32> typename>
        friend struct bsp::drv::DAConverter;
 
        static inline int s_device = -1;
    };
 
}