Subject: [PATCH] GPIO: mvebu-gpio: Don't initialize the mask_cache

From: [email-masked] (Michael Walle)
Date: Sun, 28 Oct 2012 17:33:34 +0100

Am Samstag 27 Oktober 2012, 15:28:58 schrieb Andrew Lunn:
> Due to the SMP nature of some of the chips, which have per CPU
> registers, the driver does not use the generic irq_gc_mask_set_bit() &
> irq_gc_mask_clr_bit() functions, which only support a single register.
> The driver has its own implementation of these functions, which can
> pick the correct register depending on the CPU being used. The
> functions do however use the gc->mask_cache value.
> 
> The call to irq_setup_generic_chip() was passing
> IRQ_GC_INIT_MASK_CACHE, which caused the gc->mask_cache to be
> initialized to the contents of some random register. This resulted in
> unexpected interrupts been delivered from random GPIO lines.
> 
> Signed-off-by: Andrew Lunn <[email-masked]>
> ---
>  drivers/gpio/gpio-mvebu.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
> index eb42ab1..cf7afb9 100644
> --- a/drivers/gpio/gpio-mvebu.c
> +++ b/drivers/gpio/gpio-mvebu.c
> @@ -646,7 +646,7 @@ static int __devinit mvebu_gpio_probe(struct
> platform_device *pdev) ct->handler = handle_edge_irq;
>  	ct->chip.name = mvchip->chip.label;
> 
> -	irq_setup_generic_chip(gc, IRQ_MSK(ngpios), IRQ_GC_INIT_MASK_CACHE,
> +	irq_setup_generic_chip(gc, IRQ_MSK(ngpios), 0,
>  			       IRQ_NOREQUEST, IRQ_LEVEL | IRQ_NOPROBE);
> 
>  	/* Setup irq domain on top of the generic chip. */

Tested-by: Michael Walle <[email-masked]>

Fixes my lock ups when booting, too.

-- 
Michael