Re: [PATCH v4 4/4] ARM: dts: Add exynos5250-spring device tree

["Andreas Färber" <afaerber@suse.de>]

Am 31.07.2014 21:40, schrieb Tomasz Figa:
> On 31.07.2014 21:20, Andreas Färber wrote:
>> Am 31.07.2014 21:05, schrieb Tomasz Figa:
>>> On 31.07.2014 18:08, Andreas Färber wrote:
>>>> +	usb-hub {
>>>> +		compatible = "smsc,usb3503a";
>>>> +		reset-gpios = <&hsic_reset>;
>>>
>>> Hmm, why a -gpios property points to a pinctrl node? Shouldn't there be
>>> a phandle to GPIO bank + GPIO specifier instead?
>>
>> Dunno, can change it. Can I just copy the gpio property from the
>> regulator above?
> 
> Reading what Vincent posted earlier I would consider this as the right
> thing to do and it might even let you remove the fake regulator node.

Indeed it does, thanks for spotting this!

[...]
>>>> +&dp_hpd {
>>>> +	samsung,pins = "gpc3-0";
>>>> +	samsung,pin-function = <0>;
>>>> +	samsung,pin-pud = <3>;
>>>> +	samsung,pin-drv = <0>;
>>>> +};
>>>
>>> Hmm, what node is this referencing? I believe this should rather
>>> reference the pin controller and add a new board-specific pinconf/pinmux
>>> group instead....
>>
>> It's a -pinctrl node. See v3->v4 change log and discussion on v3.
>>
> 
> Well, this is clearly a board specific node anyway, because it does not
> refer to a special function, but simply an input/interrupt GPIO. If it
> somehow has landed in generic pinctrl dtsi then it should be removed
> from there and this patch should simply introduce its own instance of
> dp_hpd node, so you did the right thing in v3.

Well, my point was that the 3.8 tree contains only one dp-hpd node, not
two as we would get by adding a new node here.

Apart from Spring, it's used in Snow and SMDK5250, so moving it there
seems feasible and the cleanest solution to me.

>>> [snip]
>>>
>>>> +/*
>>>> + * Disabled pullups since external part has its own pullups and
>>>> + * double-pulling gets us out of spec in some cases.
>>>> + */
>>>> +&i2c2_bus {
>>>> +	samsung,pin-pud = <0>;
>>>> +};
>>>
>>> OK, here overriding a generic pinconf group is justified and nicely
>>> explained by a comment.
>>
>> You seem to assume that I actually understand these things. ;)
>> Just copied from -cros-common/-snow.
>>
> 
> It is good if those things are being done with some level of
> understanding. The DT mechanics are quite well documented in
> Documentation/devicetree/bindings, while for HW-specific bits I believe
> Chromium guys could give you a hand.

I did read and even fix documentation for those bindings that I added
myself in Spring, just not for those that were already in common code,
like this one here.

A tps65090 patch has been ignored since being asked to extend the commit
message, v3 was recently sent. Help getting that in appreciated.

Cheers,
Andreas

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