Tony Lindgren <tony@xxxxxxxxxxx> writes:
> * Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> [100503 16:28]:
>> From: Chunqiu Wang <cqwang@xxxxxxxxxxxx>
>>
>> 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
>
> There's a generic solution to this problem. The solution is to temporarily
> set the level GPIO pins into edge for the duration of idle. Then
> they need to be set back to level after the system is woken up.
Sure, but that doesn't change the need for this patch which is
a correctness fix.
Adding wakeup support for level GPIOs would be a separate fix.
Kevin
>
>
>> [1] Section 25.5.3.1 OMAP34xx_ES3.1_TRM_V_Q
>>
>> Signed-off-by: Chunqiu Wang <cqwang@xxxxxxxxxxxx>
>> Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
>> ---
>> 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 678fd08..4d43cda 100644
>> --- a/arch/arm/plat-omap/gpio.c
>> +++ b/arch/arm/plat-omap/gpio.c
>> @@ -724,7 +724,11 @@ static inline void set_24xx_gpio_triggering(struct gpio_bank *bank, int gpio,
>> OMAP4_GPIO_IRQWAKEN0);
>> }
>> } else {
>> - 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
>> @@ -734,7 +738,13 @@ 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;
>> --
>> 1.7.0.2
>>
>> --
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