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* Synopsys DesignWare I2C
Required properties :
- compatible : should be "snps,designware-i2c"
or "mscc,ocelot-i2c" with "snps,designware-i2c" for fallback
- reg : Offset and length of the register set for the device
- interrupts : <IRQ> where IRQ is the interrupt number.
- clocks : phandles for the clocks, see the description of clock-names below.
The phandle for the "ic_clk" clock is required. The phandle for the "pclk"
clock is optional. If a single clock is specified but no clock-name, it is
the "ic_clk" clock. If both clocks are listed, the "ic_clk" must be first.
Recommended properties :
- clock-frequency : desired I2C bus clock frequency in Hz.
Optional properties :
- clock-names : Contains the names of the clocks:
"ic_clk", for the core clock used to generate the external I2C clock.
"pclk", the interface clock, required for register access.
- reg : for "mscc,ocelot-i2c", a second register set to configure the SDA hold
time, named ICPU_CFG:TWI_DELAY in the datasheet.
- i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds.
This option is only supported in hardware blocks version 1.11a or newer and
on Microsemi SoCs ("mscc,ocelot-i2c" compatible).
- i2c-scl-falling-time-ns : should contain the SCL falling time in nanoseconds.
This value which is by default 300ns is used to compute the tLOW period.
- i2c-sda-falling-time-ns : should contain the SDA falling time in nanoseconds.
This value which is by default 300ns is used to compute the tHIGH period.
Examples :
i2c@f0000 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "snps,designware-i2c";
reg = <0xf0000 0x1000>;
interrupts = <11>;
clock-frequency = <400000>;
};
i2c@1120000 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "snps,designware-i2c";
reg = <0x1120000 0x1000>;
interrupt-parent = <&ictl>;
interrupts = <12 1>;
clock-frequency = <400000>;
i2c-sda-hold-time-ns = <300>;
i2c-sda-falling-time-ns = <300>;
i2c-scl-falling-time-ns = <300>;
};
i2c@1120000 {
#address-cells = <1>;
#size-cells = <0>;
reg = <0x2000 0x100>;
clock-frequency = <400000>;
clocks = <&i2cclk>;
interrupts = <0>;
eeprom@64 {
compatible = "linux,slave-24c02";
reg = <0x40000064>;
};
};
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