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* I2C controller embedded in STMicroelectronics STM32 I2C platform
Required properties :
- compatible : Must be one of the following
- "st,stm32f4-i2c"
- "st,stm32f7-i2c"
- reg : Offset and length of the register set for the device
- interrupts : Must contain the interrupt id for I2C event and then the
interrupt id for I2C error.
- resets: Must contain the phandle to the reset controller.
- clocks: Must contain the input clock of the I2C instance.
- A pinctrl state named "default" must be defined to set pins in mode of
operation for I2C transfer
- #address-cells = <1>;
- #size-cells = <0>;
Optional properties :
- clock-frequency : Desired I2C bus clock frequency in Hz. If not specified,
the default 100 kHz frequency will be used.
For STM32F4 SoC Standard-mode and Fast-mode are supported, possible values are
100000 and 400000.
For STM32F7 SoC, Standard-mode, Fast-mode and Fast-mode Plus are supported,
possible values are 100000, 400000 and 1000000.
- i2c-scl-rising-time-ns : Only for STM32F7, I2C SCL Rising time for the board
(default: 25)
- i2c-scl-falling-time-ns : Only for STM32F7, I2C SCL Falling time for the board
(default: 10)
I2C Timings are derived from these 2 values
- st,syscfg-fmp: Only for STM32F7, use to set Fast Mode Plus bit within SYSCFG
whether Fast Mode Plus speed is selected by slave.
1st cell : phandle to syscfg
2nd cell : register offset within SYSCFG
3rd cell : register bitmask for FMP bit
Example :
i2c@40005400 {
compatible = "st,stm32f4-i2c";
#address-cells = <1>;
#size-cells = <0>;
reg = <0x40005400 0x400>;
interrupts = <31>,
<32>;
resets = <&rcc 277>;
clocks = <&rcc 0 149>;
pinctrl-0 = <&i2c1_sda_pin>, <&i2c1_scl_pin>;
pinctrl-names = "default";
};
i2c@40005400 {
compatible = "st,stm32f7-i2c";
#address-cells = <1>;
#size-cells = <0>;
reg = <0x40005400 0x400>;
interrupts = <31>,
<32>;
resets = <&rcc STM32F7_APB1_RESET(I2C1)>;
clocks = <&rcc 1 CLK_I2C1>;
pinctrl-0 = <&i2c1_sda_pin>, <&i2c1_scl_pin>;
pinctrl-names = "default";
st,syscfg-fmp = <&syscfg 0x4 0x1>;
};
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