cfg_i2c.h

// Copyright 2023-2025 The Aerospace Corporation.
// This file is a part of SatCat5, licensed under CERN-OHL-W v2 or later.
// Generic I2C interface
 
#pragma once
 
#include <satcat5/types.h>
 
namespace satcat5 {
    namespace util {
        struct I2cAddr final {      // GCOVR_EXCL_START
        public:
            I2cAddr() = delete;
            I2cAddr(const I2cAddr& t) = default;
            I2cAddr& operator=(const I2cAddr& t) = default;
 
            static constexpr I2cAddr addr7(u8 addr)
                {return I2cAddr(2 * addr);}
 
            static constexpr I2cAddr addr8(u8 addr)
                {return I2cAddr(addr & 0xFE);}
 
            static constexpr I2cAddr addr10(u16 addr)
                {return I2cAddr(0xF000 | ((addr&0x300)<<1) | (addr&0xFF));}
 
            static constexpr I2cAddr native(u16 addr)
                {return I2cAddr(addr);}
 
            inline bool is_10b() const {return m_addr > 255;}
 
            inline bool operator==(const I2cAddr& other) const
                {return m_addr == other.m_addr;}
            inline bool operator!=(const I2cAddr& other) const
                {return m_addr != other.m_addr;}
 
            const u16 m_addr;
 
        private:
            explicit constexpr I2cAddr(u16 addr) : m_addr(addr) {}
        };                          // GCOVR_EXCL_STOP
    }
 
    namespace cfg {
        class I2cEventListener {
        public:
            virtual void i2c_done(
                bool noack,         // Missing ACK during this command?
                const satcat5::util::I2cAddr& devaddr,  // Device address
                u32 regaddr,        // Register address (if applicable)
                unsigned nread,     // Number of bytes read (if applicable)
                const u8* rdata)    // Pointer to read buffer
                = 0;                // Child MUST override this method
        protected:
            ~I2cEventListener() {}
        };
 
        class I2cGeneric {
        public:
            virtual bool busy() = 0;
 
            virtual bool read(const satcat5::util::I2cAddr& devaddr,
                u8 regbytes, u32 regaddr, u8 nread,
                satcat5::cfg::I2cEventListener* callback = 0) = 0;
 
            virtual bool write(const satcat5::util::I2cAddr& devaddr,
                u8 regbytes, u32 regaddr, u8 nwrite, const u8* data,
                satcat5::cfg::I2cEventListener* callback = 0) = 0;
        };
    }
}