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* Freescale Inter IC (I2C) and High Speed Inter IC (HS-I2C) for i.MX
Required properties:
- compatible : Should be "fsl,<chip>-i2c"
- reg : Should contain I2C/HS-I2C registers location and length
- interrupts : Should contain I2C/HS-I2C interrupt
Optional properties:
- clock-frequency : Constains desired I2C/HS-I2C bus clock frequency in Hz.
The absence of the propoerty indicates the default frequency 100 kHz.
Examples:
i2c@83fc4000 { /* I2C2 on i.MX51 */
compatible = "fsl,imx51-i2c", "fsl,imx21-i2c";
reg = <0x83fc4000 0x4000>;
interrupts = <63>;
};
i2c@70038000 { /* HS-I2C on i.MX51 */
compatible = "fsl,imx51-i2c", "fsl,imx21-i2c";
reg = <0x70038000 0x4000>;
interrupts = <64>;
clock-frequency = <400000>;
};
The driver can provide recovery functionality for cases were the bus gets
stuck with SDA pulled low.
In order to enable this one has to specify an additional pinctrl property with
the name 'recovery' to mux GPIO functionality on SDA/SCL and a gpios
property with the GPIOs for SDA/SCL.
The lack of the gpios property disables the functionality.
Examples:
&i2c3 {
clock-frequency = <100000>;
pinctrl-names = "default", "recovery";
pinctrl-0 = <&pinctrl_i2c3_1>;
pinctrl-1 = <&pinctrl_i2c3_recovery_1>;
gpios = <&gpio3 18 0 /* sda */
&gpio3 17 0 /* scl */
>;
status = "disabled";
};
When e.g. a device driver detects a stuck bus
int i2c_recover_bus(struct i2c_adapter *adap)
can be called to try to recover the bus.
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