[PATCH 05/33] gpio: add generic single-register fixed-direction GPIO driver

[Linus Walleij]

On Mon, Sep 5, 2016 at 2:26 PM, Russell King - ARM Linux
<linux at armlinux.org.uk> wrote:
> On Mon, Sep 05, 2016 at 11:06:28AM +0200, Linus Walleij wrote:
>> I couldn't resist testing on the Compaq iPAQ h3600. It works the
>> same as before so:
>> Tested-by: Linus Walleij <linus.walleij at linaro.org> [for Compaq iPAQ H3600]
>
> Great news.  I've been thinking about digging out my h3600, but it's
> very old, and hasn't been turned on for many years.  I'm not sure what
> state it's in.
>
> I've been hoping to try booting some kernels with qemu-system-arm, but
> so far I've completely failed to get qemu-system-arm to do anything
> useful - it just sits there doing apparently nothing, irrespective of
> which platform I choose or which kernel I give it.
>
>> The only news in the bootlog is this:
>> sa11x0-pcmcia: probe of sa11x0-pcmcia failed with error -2
>
> Not so great news - that's -ENOENT.  Did that happen before these
> changes?  That could be that the gpiod lookup table isn't found.
> However, if that were the case, I'd have expected an error message
> along the lines of:
>
> Failed to get GPIO for xxx: -nnn
>
> from soc_pcmcia_request_gpiods().  The other possibility is that
> we're not getting to sa11x0_drv_pcmcia_legacy_probe() but instead
> trying to initialise it as a generic sa11x0 socket, and
> sa11x0_pcmcia_hw_init() is failing as a result.
>
> We should be using the legacy probe on H3600, so sa11x0_pcmcia_hw_init()
> should never be reached.

However that is what happens, this is my callstack after
adding some prints:

sa11x0_pcmcia_init
sa11x0_drv_pcmcia_probe
soc_pcmcia_init_one
soc_pcmcia_add_one
soc_pcmcia_hw_init
sa11x0_pcmcia_hw_init
soc_pcmcia_add_one: pcmcia HW init failed
sa11x0-pcmcia: probe of sa11x0-pcmcia failed with error -2

It bails out when trying to get the "reset" gpio.

I'm trying to figure out how this can happen.

On the plus side: this minor snag is all the problems I have.
All other GPIOs work exactly as they should.

Yours,
Linus Walleij