[PATCH] pxa: fix gpio_to_irq() for GPIOs on expander chips

[pHilipp Zabel]

On Wed, Nov 25, 2009 at 12:36 PM, Dmitry Artamonow <mad_soft at inbox.ru> wrote:
> Commit 9db95cb6c430b added support for gpios on PXA93x/950 and
> increased PXA_GPIO_IRQ_NUM from 128 to 192, but missed to update
> NR_BUILTIN_GPIO. This led to broken gpio_to_irq() for off-chip GPIOs.
> Adjust NR_BUILTIN_GPIO accordingly, and also increase ARCH_NR_GPIOS,
> as there exist platforms (hx4700) with more than 64 off-chip GPIOs,
> so default value 256 is not enough.
>
> Signed-off-by: Dmitry Artamonow <mad_soft at inbox.ru>

Hi, are there any opinions on this one?

Personally, I'd prefer not to increase PXA_GPIO_IRQ_NUM to 196 unless
PXA9xx support is enabled. But as it is now, we either need to
increase NR_BUILTIN_GPIO and ARCH_NR_GPIOS too (moving hx4700's 70
ASIC3 GPIOs to 196..265), or add support for the gpiolib to_irq method
to the PXA gpio_to_irq macro (which Eric didn't like, see the thread
at http://www.spinics.net/lists/arm-kernel/msg53803.html) in order to
keep the ASIC3 GPIOs in the 128...197 range.

regards
Philipp

> ---
>  arch/arm/mach-pxa/include/mach/gpio.h |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
>
> This is a fix for 2.6.32 regression.
> Found this while testing 2.6.32-rc8 on hx4700. Here's errors in log
> on unpatched kernel (all related to gpios on ASIC3 chip):
> [   37.369051] gpio-vbus gpio-vbus: can't request irq 286, err: -22
> [   37.398158] gpio-vbus: probe of gpio-vbus failed with error -22
> ...
> [   37.683452] gpio-keys: Unable to claim irq 278; error -22
> [   37.700759] gpio-keys: probe of gpio-keys failed with error -22
> ...
> [   38.025748] pda-power pda-power: request ac irq failed
> [   38.044569] pda-power: probe of pda-power failed with error -22
>
> And after increasing NR_BUILTIN_GPIO to 192, I got this:
> [  207.323467] gpiochip_add: gpios 256..263 (htc-egpio) not registered
>
> With both NR_BUILTIN_GPIO and ARCH_NR_GPIOS increased there's no more
> gpio-related errors.
>
> I'm a bit unsure if this patch don't have any side effects on other PXA
> platforms, and I even don't understand how exactly NR_BUILTIN_GPIO
> and PXA_GPIO_IRQ_NUM affect gpios on expanders, so please check thoroughly!
>
> diff --git a/arch/arm/mach-pxa/include/mach/gpio.h b/arch/arm/mach-pxa/include/mach/gpio.h
> index b024a8b..bf53894 100644
> --- a/arch/arm/mach-pxa/include/mach/gpio.h
> +++ b/arch/arm/mach-pxa/include/mach/gpio.h
> @@ -24,6 +24,8 @@
>  #ifndef __ASM_ARCH_PXA_GPIO_H
>  #define __ASM_ARCH_PXA_GPIO_H
>
> +#define ARCH_NR_GPIOS  320
> +
>  #include <mach/irqs.h>
>  #include <mach/hardware.h>
>  #include <asm-generic/gpio.h>
> @@ -99,7 +101,7 @@
>  #define GAFR(x)                GPIO_REG(0x54 + (((x) & 0x70) >> 2))
>
>
> -#define NR_BUILTIN_GPIO 128
> +#define NR_BUILTIN_GPIO 192
>
>  #define gpio_to_bank(gpio)     ((gpio) >> 5)
>  #define gpio_to_irq(gpio)      IRQ_GPIO(gpio)
> --
> 1.6.3.4
>
>