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Diffstat (limited to 'doc/device-tree-bindings')
| -rw-r--r-- | doc/device-tree-bindings/i2c/i2c-designware.txt | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/doc/device-tree-bindings/i2c/i2c-designware.txt b/doc/device-tree-bindings/i2c/i2c-designware.txt new file mode 100644 index 0000000000..be766be812 --- /dev/null +++ b/doc/device-tree-bindings/i2c/i2c-designware.txt @@ -0,0 +1,73 @@ +* 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>; + };x + + 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>; + }; + }; |