[U-Boot] [PATCH 2/3] Tegra30: fdt: Update DT files with I2C info for T30/Cardhu

Tom Warren twarren.nvidia at gmail.com
Wed Jan 2 21:58:56 CET 2013


Alrightly. Can you send me a link to the latest-and-greatest
T30/Cardhu kernel DT files so I can use 'em as a reference? Every time
I do a Google search for kernel files I'm never sure if I've got the
latest one or not.

Thanks

On Wed, Jan 2, 2013 at 1:41 PM, Stephen Warren <swarren at wwwdotorg.org> wrote:
> On 12/21/2012 05:16 PM, Tom Warren wrote:
>> Note that T30 does not have a separate/different DVC (power I2C)
>> controller like T20 - all 5 I2C controllers are identical, but
>> DVC_I2C is still used to designate the controller intended for
>> power control (PWR_I2C in the schematics). On Cardhu, it's used
>> to access the PMU and EEPROM, as well as the audio codec, temp
>> sensor, and fuel gauge devices from the OS.
>
>> diff --git a/arch/arm/dts/tegra30.dtsi b/arch/arm/dts/tegra30.dtsi
>
>> +     tegra_car: clock at 60006000 {
>> +             compatible = "nvidia,tegra30-car", "nvidia,tegra20-car";
>> +             reg = <0x60006000 0x1000>;
>> +             #clock-cells = <1>;
>> +     };
>> +
>> +     clocks {
>
> It'd be nice to keep the DT nodes sorted in the same order they are in
> the kernel. There, the rules are that nodes appears in order:
>
> 1) Any nodes from /include/d files, in the order they appeared in the
> underlying file.
>
> 2) Any nodes with a reg property, in order of the address in the reg
> property.
>
> 3) Any nodes without a reg property, in alphabetical order by node name.
>
> This will allow the U-Boot and kernel DT files to be more easily
> compared/diff'd.
>
> The clocks and osc node would usually be part of the board file, not the
> SoC file, I believe...
>
> Actually, the clocks "osc" and (later) "clk_32k" don't appear to be used
> anywhere; can we just drop their nodes until if/when they are?
>
>> +     i2c at 7000c000 {
>> +             #address-cells = <1>;
>> +             #size-cells = <0>;
>> +             compatible = "nvidia,tegra30-i2c", "nvidia,tegra20-i2c";
>> +             reg = <0x7000C000 0x100>;
>> +             /* PERIPH_ID_I2C1, CLK_M */
>> +             clocks = <&tegra_car 12>;
>> +     };
>
> I think we should use lower-case for all hex constants in the DT. Also,
> can the properties appear in the same order as in the kernel DT files so
> they're easier to compare/diff.
>
> Also, the SoC .dtsi file should have status="disabled" for all the
> optionally-used HW modules, and the board files set status="okay" for
> those that the board actually uses.


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