rt-thread/components/drivers/i2c/Kconfig

menuconfig RT_USING_I2C
    bool "Using I2C device drivers"
    default n
    help
      Enable the RT-Thread I2C core so both DM aware controllers and legacy bus
      drivers can register `struct rt_i2c_bus_device` objects, and client
      drivers can issue transfers through the unified APIs. Select this on any
      board that exposes an I2C peripheral or software bit-bang bus; disable it
      only if you never interface with I2C sensors/PMICs/MCUs.

if RT_USING_I2C
    config RT_I2C_DEBUG
        bool "Use I2C debug message"
        default n
        help
          Print verbose I2C transaction logs (start/stop, address, data) to the
          console. Helpful while debugging board bring-up, but it slows down the
          bus and should remain off in production firmware.

    config RT_USING_I2C_BITOPS
        bool "Use GPIO to simulate I2C"
        default y
        help
          Build the generic bit-banging algorithm (`dev_i2c_bit_ops.c`) so
          controller drivers or the software I2C backend can drive SCL/SDA pins
          directly. Disable this only when every I2C controller is hardware-
          assisted and you want to shave a few hundred bytes of code.

    if RT_USING_I2C_BITOPS
        config RT_I2C_BITOPS_DEBUG
            bool "Use simulate I2C debug message"
            default n
            help
              Emit timing-level diagnostics from the bit-bang implementation,
              showing whether GPIO toggles are happening as expected. Useful to
              diagnose board wiring or timing issues, but generates a lot of log
              traffic and should stay disabled normally.
    endif

    menuconfig RT_USING_SOFT_I2C
        bool "Use GPIO to soft simulate I2C"
        default n
        select RT_USING_PIN
        select RT_USING_I2C_BITOPS
        help
          Instantiate one or more fully software I2C buses backed by GPIO pins.
          Each enabled bus entry below lets you choose SCL/SDA pin numbers, the
          exported bus name, and bit-bang timing. Use this when the SoC lacks an
          available controller but you still need to connect low-speed sensors.
        if RT_USING_SOFT_I2C
            menuconfig RT_USING_SOFT_I2C0
                bool "Enable I2C0 Bus (software simulation)"
                default y
                help
                  Create a software I2C bus named by `RT_SOFT_I2C0_BUS_NAME`
                  using the selected SCL/SDA pins. Disable it if the board does
                  not wire up a first soft I2C channel.
                if RT_USING_SOFT_I2C0
                    config RT_SOFT_I2C0_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 1
                    config RT_SOFT_I2C0_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 2
                    config RT_SOFT_I2C0_BUS_NAME
                        string "Bus name"
                        default "i2c0"
                    config RT_SOFT_I2C0_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C0_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C1
                bool "Enable I2C1 Bus (software simulation)"
                default y
                help
                  Enable the second software I2C controller and configure its
                  pins/name/timing below when multiple bit-bang buses are wired
                  out on the PCB.
                if RT_USING_SOFT_I2C1
                    config RT_SOFT_I2C1_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 3
                    config RT_SOFT_I2C1_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 4
                    config RT_SOFT_I2C1_BUS_NAME
                        string "Bus name"
                        default "i2c1"
                    config RT_SOFT_I2C1_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C1_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C2
                bool "Enable I2C2 Bus (software simulation)"
                default n
                help
                  Optional third soft I2C bus for boards that expose additional
                  GPIO pairs. Turn this on only if you really route the
                  corresponding pins.
                if RT_USING_SOFT_I2C2
                    config RT_SOFT_I2C2_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 5
                    config RT_SOFT_I2C2_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 6
                    config RT_SOFT_I2C2_BUS_NAME
                        string "Bus name"
                        default "i2c2"
                    config RT_SOFT_I2C2_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C2_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C3
                bool "Enable I2C3 Bus (software simulation)"
                default n
                help
                  Same as above but for the fourth software I2C instance.
                if RT_USING_SOFT_I2C3
                    config RT_SOFT_I2C3_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 7
                    config RT_SOFT_I2C3_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 8
                    config RT_SOFT_I2C3_BUS_NAME
                        string "Bus name"
                        default "i2c3"
                    config RT_SOFT_I2C3_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C3_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C4
                bool "Enable I2C4 Bus (software simulation)"
                default n
                help
                  Enable the fifth configurable bit-bang bus if more GPIO-based
                  channels are required.
                if RT_USING_SOFT_I2C4
                    config RT_SOFT_I2C4_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 9
                    config RT_SOFT_I2C4_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C4_BUS_NAME
                        string "Bus name"
                        default "i2c4"
                    config RT_SOFT_I2C4_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C4_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C5
                bool "Enable I2C5 Bus (software simulation)"
                default n
                help
                  Enable the sixth configurable bit-bang bus when the hardware
                  exposes yet another sensor connector.
                if RT_USING_SOFT_I2C5
                    config RT_SOFT_I2C5_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 11
                    config RT_SOFT_I2C5_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 12
                    config RT_SOFT_I2C5_BUS_NAME
                        string "Bus name"
                        default "i2c5"
                    config RT_SOFT_I2C5_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C5_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C6
                bool "Enable I2C6 Bus (software simulation)"
                default n
                help
                  Enable the seventh software bus; use only on complex boards
                  because each additional bus increases code/data usage.
                if RT_USING_SOFT_I2C6
                    config RT_SOFT_I2C6_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 13
                    config RT_SOFT_I2C6_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 14
                    config RT_SOFT_I2C6_BUS_NAME
                        string "Bus name"
                        default "i2c6"
                    config RT_SOFT_I2C6_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C6_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C7
                bool "Enable I2C7 Bus (software simulation)"
                default n
                help
                  Provide an eighth configurable software bus if still more GPIO
                  pairs are required for isolated peripherals.
                if RT_USING_SOFT_I2C7
                    config RT_SOFT_I2C7_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 15
                    config RT_SOFT_I2C7_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 16
                    config RT_SOFT_I2C7_BUS_NAME
                        string "Bus name"
                        default "i2c7"
                    config RT_SOFT_I2C7_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C7_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
            menuconfig RT_USING_SOFT_I2C8
                bool "Enable I2C8 Bus (software simulation)"
                default n
                help
                  Final reserved entry for a ninth soft I2C controller. Enable
                  it only when the design needs that many bit-bang buses; leave
                  disabled otherwise to save resources.
                if RT_USING_SOFT_I2C8
                    config RT_SOFT_I2C8_SCL_PIN
                        int "SCL pin number"
                        range 0 32767
                        default 17
                    config RT_SOFT_I2C8_SDA_PIN
                        int "SDA pin number"
                        range 0 32767
                        default 18
                    config RT_SOFT_I2C8_BUS_NAME
                        string "Bus name"
                        default "i2c8"
                    config RT_SOFT_I2C8_TIMING_DELAY
                        int "Timing delay (us)"
                        range 0 32767
                        default 10
                    config RT_SOFT_I2C8_TIMING_TIMEOUT
                        int "Timing timeout (tick)"
                        range 0 32767
                        default 10
                endif
        endif
endif

if RT_USING_DM && RT_USING_I2C
    osource "$(SOC_DM_I2C_DIR)/Kconfig"
endif