[PATCH 6/6] ARM: dts: hummingboard: gpio-ir on gpio 3,5

[Fabio Estevam]

On Sat, Aug 23, 2014 at 10:36 AM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Sat, Aug 23, 2014 at 10:32:23AM -0300, Fabio Estevam wrote:
>> On Sat, Aug 23, 2014 at 6:11 AM, Russell King
>> <rmk+kernel at arm.linux.org.uk> wrote:
>>
>> > -                               MX6QDL_PAD_GPIO_2__GPIO1_IO02 0x80000000
>> > +                               MX6QDL_PAD_EIM_DA5__GPIO3_IO05 0x80000000
>>
>> It would be better to replace the '0x80000000' with the real iomux
>> value (like 0x1b0b0 for example), so that we do not need to rely on
>> the bootloader doing the correct configuration for us.
>
> I'd just end up choosing something which appears to work - I've no idea
> at present what an appropriate value should be here.

In the working system, you could read the register:

IOMUXC_SW_PAD_CTL_PAD_EIM_AD05 (address: 0x20E043C)

Most likely it will return the default value of 0xb0b1 if the
bootloader has not re-configured it.

,and then put this read value into the device tree. This way we
guarantee that the kernel will have this pin correctly configured,
without depending on the bootloader.