Re: [PATCH 1/1] gpio: add a driver for the Synopsys DesignWare APBGPIO block

[Rob Herring]

On Wed, Nov 20, 2013 at 3:47 PM, delicious quinoa
<delicious.quinoa@xxxxxxxxx> wrote:
> On Thu, Nov 7, 2013 at 6:33 AM, Sebastian Hesselbarth
> <sebastian.hesselbarth@xxxxxxxxx> wrote:
>> On 11/06/13 23:49, Alan Tull wrote:

[snip]

>> BTW, what if we get rid of port child nodes completely and rather
>> use:
>>
>> gpio: gpio-controller@20000 {
>>         compatible = "snps,dw-apb-gpio";
>>         reg = <0x20000 0x1000>;
>>         gpio-controller;
>>         #gpio-cells = <2>;
>>         interrupt-controller;
>>         interrupt-parent = <&vic1>;
>>         interrupts = <0 1 2 3 4 5 6 7>;
>>         snps,port-widths = <8 8 0 0>;
>> };
>>
>> The only draw-back compared to child-nodes is, that you'll reference
>> gpios with <&gpio 13> instead of <&banka 5>. I have no strong opinion
>> about it, so I leave the correct answer to either LinusW or DT
>> maintainers.
>
> I left this as-is for now.

I generally favor less nodes of things, but I think we discussed this
when originally posted and keeping them seemed to be the right choice.
What if you have sparsely populated banks like this:

snps,port-widths = <4 4 0 0>;
snps,port-widths = <8 0 8 0>;

Also, you would need to define how the interrupts are done. You may
have 1 per port or 1 per gpio line or a mixture if the h/w folks
really hate you.

Rob
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