[PATCH v2] ARM: tegra: add Acer Chromebook 13 device tree

Stephen Warren swarren at wwwdotorg.org
Thu Sep 4 14:04:55 PDT 2014

On 09/04/2014 02:33 PM, Dylan Reid wrote:
> On Thu, Sep 4, 2014 at 12:40 PM, Stephen Warren <swarren at wwwdotorg.org> wrote:
>> On 08/13/2014 01:14 PM, Dylan Reid wrote:
>>> The Acer Chromebook 13, codenamed Big, contains an NVIDIA tegra124
>>> processor and is similar to the Venice2 reference platform.
>>> The keyboard, USB 2, audio, HDMI, sdcard, and emmc have been tested
>>> and work on the 1266x768 models.  The HD models haven't yet been
>>> tested.
>>> WiFi does not work yet, it needs at least some PMIC changes to enable
>>> the 32k clock.
>>> The elan trackpad is not yet functional but hopefully will be soon as
>>> there are patches under review.
>>> There is also an issue on reboot because the TPM isn't reset.  It will
>>> cause the stock firmware to enter recovery mode.  This can be worked
>>> around by an EC-reset, press the refresh and power keys at the same
>>> time.
>> BTW, I'm only waiting on a few minor fixes for issues pointed out by Andreas
>> before applying this patch:
> Thanks Stephen,
> Sorry I've been MIA, things have been a little crazy here.
>> * Resolution typo in the commit message.
>> * Sort order of the Makefile addition.
>> * pwm: label move.
> If I move the pwm label, should I move the others as well?  Do we want
> to use the same method that has been used for exynos5250?  Exynos has
> a label on most things that are overridden and the .dts files that
> override them, like exynos5250-snow.dts, access them with &label
> syntax.  It's easy for me to do, but it will involve converting
> venice2 and jetson as well to avoid label re-defines.

I think anything that's first defined in tegra124.dtsi should have the 
label defined in tegra124.dtsi, provided the label makes sens across all 
boards. From v2 of the patch, that looks like: dpaux, pwm. It looks like 
the pinmux label isn't used, so I'd suggest dropping that. The label 
name hdmi_ddc feels board-specific (since different boards could at 
least theoretically use different I2C controllers for DDC), so I'd leave 
that in the board dts file myself.

The &label { ... } syntax wouldn't be consistent with any of the other 
Tegra files at the moment, so I'd suggest sticking to the overall DT 
structure you already have in patch v2. I admit it's unfortunate that 
Exynos and Tegra use different node reference styles, but consistency 
between all the Tegra DT files feels most important to me right now:-)

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