Re: [PATCH] [OMAP] GPIO Module is reset during initialization

[Felipe Balbi <me@felipebalbi.com>]

On Fri, Oct 23, 2009 at 09:25:29PM +0530, charu@ti.com wrote:
> From: Charulatha V <charu@ti.com>
> 
> During initialization, GPIO module is reset using soft reset bit
> of SYSCONFIG register
> 
> Signed-off-by: Charulatha V <charu@ti.com>
> ---
>  arch/arm/plat-omap/gpio.c |   12 +++++++++++-
>  1 files changed, 11 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
> index 2304a5d..4579650 100644
> --- a/arch/arm/plat-omap/gpio.c
> +++ b/arch/arm/plat-omap/gpio.c
> @@ -21,6 +21,7 @@
>  #include <linux/err.h>
>  #include <linux/clk.h>
>  #include <linux/io.h>
> +#include <linux/delay.h>
>  
>  #include <mach/hardware.h>
>  #include <asm/irq.h>
> @@ -1670,7 +1671,7 @@ static int __init _omap_gpio_init(void)
>  	}
>  #endif
>  	for (i = 0; i < gpio_bank_count; i++) {
> -		int j, gpio_count = 16;
> +		int j, gpio_count = 16, attempt = 0;

decrementing is better, so:

attempt = 1000

>  
>  		bank = &gpio_bank[i];
>  		spin_lock_init(&bank->lock);
> @@ -1698,6 +1699,15 @@ static int __init _omap_gpio_init(void)
>  			static const u32 non_wakeup_gpios[] = {
>  				0xe203ffc0, 0x08700040
>  			};
> +
> +		/* Software Reset of GPIO module */
> +		__raw_writel(0x0002, bank->base	+ OMAP24XX_GPIO_SYSCONFIG);
> +		while (((__raw_readl(bank->base + OMAP24XX_GPIO_SYSSTATUS)
> +					& 0x1) == 0) && attempt < 5) {

&& attemp)

> +			udelay(1);

i guess cpu_relax() is better here.

> +			attempt++;

attempt--;

-- 
balbi