Re: [PATCH] Doc: dt: i2c: tegra: add dt binding for i2c-tegra

From: Grant Likely
Date: Mon Apr 15 2013 - 09:08:54 EST


On Mon, 18 Mar 2013 15:05:50 +0530, Laxman Dewangan <ldewangan@xxxxxxxxxx> wrote:
> Add documentation for device tree binding of NVIDIA's Tegra i2c
> controller driver.
>
> Describing all compatible values used for diffenent Tegra SoCs
> in details in this documentation.
>
> Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx>

Looks fine by me

Acked-by: Grant Likely <grant.likely@xxxxxxxxxxxx>

Should be merged with the driver series.

g.

> ---
> .../devicetree/bindings/i2c/nvidia,tegra20-i2c.txt | 99 ++++++++++++++++++++
> 1 files changed, 99 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/i2c/nvidia,tegra20-i2c.txt
>
> 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..e390ce8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/nvidia,tegra20-i2c.txt
> @@ -0,0 +1,99 @@
> +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".
> +
> +
> +Typical i2c node for Tegra20:
> + 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";
> + };
> +
> +Typical dvc-i2c node for Tegra20:
> + i2c@7000d000 {
> + compatible = "nvidia,tegra20-i2c-dvc";
> + reg = <0x7000d000 0x200>;
> + interrupts = <0 53 0x04>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + clocks = <&tegra_car 47>, <&tegra_car 124>;
> + clock-names = "div-clk", "fast-clk";
> + status = "disabled";
> + };
> +
> +Typical i2c node for Tegra30:
> + i2c@7000c000 {
> + compatible = "nvidia,tegra30-i2c", "nvidia,tegra20-i2c";
> + reg = <0x7000c000 0x100>;
> + interrupts = <0 38 0x04>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + clocks = <&tegra_car 12>, <&tegra_car 182>;
> + clock-names = "div-clk", "fast-clk";
> + status = "disabled";
> + };
> +
> +Typical i2c node for Tegra114:
> + i2c@7000c000 {
> + compatible = "nvidia,tegra114-i2c";
> + reg = <0x7000c000 0x100>;
> + interrupts = <0 38 0x04>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + status = "disabled";
> + clocks = <&tegra_car 12>;
> + clock-names = "div-clk";
> + };
> --
> 1.7.1.1
>

--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.
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