Hi Magnus,
On Fri, Oct 13, 2017 at 4:30 AM, Magnus Damm <magnus.damm@xxxxxxxxx> wrote:
> On Thu, Oct 12, 2017 at 3:56 PM, Geert Uytterhoeven
> <geert@xxxxxxxxxxxxxx> wrote:
>> On Wed, Oct 11, 2017 at 11:39 PM, Marek Vasut <marek.vasut@xxxxxxxxx> wrote:
>>> On 10/10/2017 04:58 PM, Geert Uytterhoeven wrote:
>>>> Add a device node for the ROHM BD9571MWV PMIC, based on the example in
>>>> the DT binding documentation, but using INTC-EX instead.
>>>>
>>>> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>>>> --- a/arch/arm64/boot/dts/renesas/salvator-common.dtsi
>>>> +++ b/arch/arm64/boot/dts/renesas/salvator-common.dtsi
>>>> @@ -353,6 +353,30 @@
>>>>
>>>> &i2c_dvfs {
>>>> status = "okay";
>>>> +
>>>> + pmic: pmic@30 {
>>>> + pinctrl-0 = <&irq0_pins>;
>>>> + pinctrl-names = "default";
>>>> +
>>>> + compatible = "rohm,bd9571mwv";
>>>> + reg = <0x30>;
>>>> + interrupt-parent = <&intc_ex>;
>>>
>>> Shouldn't this be gpio2 ? Why intc-ex ?
>>
>> Because we now have INTC-EX support ;-)
>>
>> Serious: if a pin used for interrupt signalling can be configured for both
>> GPIO and INTC-EX aka IRQC, we typically configure it for INTC-EX. Probably
>> because the latter is a simpler block, and thus consumes less power?
>
> I agree with your decision to use INTC-EX over GPIO, however I do
> think that this discussion smells like software policy...
>
> Isn't DT supposed to describe the hardware? =)
>
> It's almost like we want to DT to point out the pin, not the function....
Then we should describe all INTC-EX pins using the (not yet upstream?)
DT connector framework, which can describe the pins can be served by
both INTC-EX and GPIO2. I'm afraid it's too early for that.
Note that lots of functionality can be served by General Purpose I/O instead
of dedicated hardware. That doesn't mean it's always a good idea to do so....
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
