[PATCH v3 07/15] ARM: mxs: Add gpio support

[Shawn Guo]

Hi Uwe,

2010/12/10 Uwe Kleine-König <u.kleine-koenig at pengutronix.de>:
> Hello Shawn,
>
> On Fri, Dec 10, 2010 at 03:23:13PM +0800, Shawn Guo wrote:
>> On Fri, Dec 10, 2010 at 3:06 PM, Shawn Guo <shawn.gsc at gmail.com> wrote:
>> > On Fri, Dec 10, 2010 at 12:47 AM, Lothar Waßmann <LW at karo-electronics.de> wrote:
>> >> Shawn Guo writes:
>> >>> +static void _set_gpio_irqenable(struct mxs_gpio_port *port, u32 index,
>> >>> +                             int enable)
>> >>> +{
>> >>> +     if (enable == 0) {
>> >>> +             __raw_writel(1 << index,
>> >>> +                     port->base + PINCTRL_PIN2IRQ(port->id) + MXS_CLR_ADDR);
>> >>> +             __raw_writel(1 << index,
>> >>> +                     port->base + PINCTRL_IRQEN(port->id) + MXS_CLR_ADDR);
>> >> This will loose interrupt pulses that happen while IRQs are disabled.
>> >> IMO PIN2IRQ should only be cleared when an IRQ is freed, not when it
>> >> is disabled.
>> >>
>> > What about leaving PIN2IRQ always be 1 and only using IRQEN to
>> > enable/disable IRQ?  I consulted the designer it's no problem no
>> > matter what the pin function is.
>> >
>> The code will be like:
>>
>> static void _set_gpio_irqenable(struct mxs_gpio_port *port, u32 index,
>>                                 int enable)
>> {
>>         if (enable) {
>>                 __raw_writel(1 << index,
>>                         port->base + PINCTRL_IRQEN(port->id) + MXS_SET_ADDR);
>>                 __raw_writel(1 << index,
>>                         port->base + PINCTRL_PIN2IRQ(port->id) + MXS_SET_ADDR);
>>         } else {
>>                 __raw_writel(1 << index,
>>                         port->base + PINCTRL_IRQEN(port->id) + MXS_CLR_ADDR);
>>         }
>> }
> If I understood Lothar correctly the best way is to set and clear
> PINCTRL_PIN2IRQ in the irqchips irq_startup and irq_shutdown routine.
>
Is there any problem with the current code to address Lothar's
concern?  If no, I would not introduce two more irq_chip routines into
the file.

-- 
Regards,
Shawn