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Diffstat (limited to 'Documentation/devicetree')
| -rw-r--r-- | Documentation/devicetree/bindings/i2c/nvidia,tegra20-i2c.txt | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/i2c/nvidia,tegra20-i2c.txt b/Documentation/devicetree/bindings/i2c/nvidia,tegra20-i2c.txt new file mode 100644 index 0000000..ef77cc7 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/nvidia,tegra20-i2c.txt @@ -0,0 +1,60 @@ +NVIDIA Tegra20/Tegra30/Tegra114 I2C controller driver. + +Required properties: +- compatible : should be: + "nvidia,tegra114-i2c" + "nvidia,tegra30-i2c" + "nvidia,tegra20-i2c" + "nvidia,tegra20-i2c-dvc" + Details of compatible are as follows: + nvidia,tegra20-i2c-dvc: Tegra20 has specific I2C controller called as DVC I2C + controller. This only support master mode of I2C communication. Register + interface/offset and interrupts handling are different than generic I2C + controller. Driver of DVC I2C controller is only compatible with + "nvidia,tegra20-i2c-dvc". + nvidia,tegra20-i2c: Tegra20 has 4 generic I2C controller. This can support + master and slave mode of I2C communication. The i2c-tegra driver only + support master mode of I2C communication. Driver of I2C controller is + only compatible with "nvidia,tegra20-i2c". + nvidia,tegra30-i2c: Tegra30 has 5 generic I2C controller. This controller is + very much similar to Tegra20 I2C controller with additional feature: + Continue Transfer Support. This feature helps to implement M_NO_START + as per I2C core API transfer flags. Driver of I2C controller is + compatible with "nvidia,tegra30-i2c" to enable the continue transfer + support. This is also compatible with "nvidia,tegra20-i2c" without + continue transfer support. + nvidia,tegra114-i2c: Tegra114 has 5 generic I2C controller. This controller is + very much similar to Tegra30 I2C controller with some hardware + modification: + - Tegra30/Tegra20 I2C controller has 2 clock source called div-clk and + fast-clk. Tegra114 has only one clock source called as div-clk and + hence clock mechanism is changed in I2C controller. + - Tegra30/Tegra20 I2C controller has enabled per packet transfer by + default and there is no way to disable it. Tegra114 has this + interrupt disable by default and SW need to enable explicitly. + Due to above changes, Tegra114 I2C driver makes incompatible with + previous hardware driver. Hence, tegra114 I2C controller is compatible + with "nvidia,tegra114-i2c". +- reg: Should contain I2C controller registers physical address and length. +- interrupts: Should contain I2C controller interrupts. +- address-cells: Address cells for I2C device address. +- size-cells: Size of the I2C device address. +- clocks: Clock ID as per + Documentation/devicetree/bindings/clock/tegra<chip-id>.txt + for I2C controller. +- clock-names: Name of the clock: + Tegra20/Tegra30 I2C controller: "div-clk and "fast-clk". + Tegra114 I2C controller: "div-clk". + +Example: + + i2c@7000c000 { + compatible = "nvidia,tegra20-i2c"; + reg = <0x7000c000 0x100>; + interrupts = <0 38 0x04>; + #address-cells = <1>; + #size-cells = <0>; + clocks = <&tegra_car 12>, <&tegra_car 124>; + clock-names = "div-clk", "fast-clk"; + status = "disabled"; + }; |
