Re: [PATCH -pm] OMAP3: GPIO: Only enable WAKEUPEN for edge detection GPIOs

[Kevin Hilman <khilman@deeprootsystems.com>]

Kevin Hilman <khilman@deeprootsystems.com> writes:

> From: Chunqiu Wang <cqwang@motorola.com>
>
> According to the GPIO 'Wakeup and Interrupt' section of the TRM[1],
> wake-up requests can only be generated on edge transitions.
>
> Also for OMAP3, only edge GPIOs may lose interrupts when PER enters
> RET/OFF state, this is addressed by gpio prepare|resume idle functions
>
> [1] Section 25.5.3.1 OMAP34xx_ES3.1_TRM_V_Q
>
> Signed-off-by: Chunqiu Wang <cqwang@motorola.com>
> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

Pushing to PM branch, and backport to pm-2.6.29.

Kevin

> ---
>  arch/arm/plat-omap/gpio.c |   14 ++++++++++++--
>  1 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
> index 8e6f511..de61a13 100644
> --- a/arch/arm/plat-omap/gpio.c
> +++ b/arch/arm/plat-omap/gpio.c
> @@ -684,7 +684,11 @@ static inline void set_24xx_gpio_triggering(struct gpio_bank *bank, int gpio,
>  		trigger & IRQ_TYPE_EDGE_FALLING);
>  
>  	if (likely(!(bank->non_wakeup_gpios & gpio_bit))) {
> -		if (trigger != 0)
> +		/*
> +		 * GPIO wakeup request can only be generated on edge
> +		 * transitions
> +		 */
> +		if (trigger & IRQ_TYPE_EDGE_BOTH)
>  			__raw_writel(1 << gpio, bank->base
>  					+ OMAP24XX_GPIO_SETWKUENA);
>  		else
> @@ -693,7 +697,13 @@ static inline void set_24xx_gpio_triggering(struct gpio_bank *bank, int gpio,
>  	}
>  	/* This part needs to be executed always for OMAP34xx */
>  	if (cpu_is_omap34xx() || (bank->non_wakeup_gpios & gpio_bit)) {
> -		if (trigger != 0)
> +		/*
> +		 * Log the edge gpio and manually trigger the IRQ
> +		 * after resume if the input level changes
> +		 * to avoid irq lost during PER RET/OFF mode
> +		 * Applies for omap2 non-wakeup gpio and all omap3 gpios
> +		 */
> +		if (trigger & IRQ_TYPE_EDGE_BOTH)
>  			bank->enabled_non_wakeup_gpios |= gpio_bit;
>  		else
>  			bank->enabled_non_wakeup_gpios &= ~gpio_bit;
> -- 
> 1.6.3.2