Re: [RFC v2] gpio/omap: auto-setup a GPIO when used as an IRQ

From: Tony Lindgren
Date: Tue Sep 24 2013 - 11:58:28 EST


* Santosh Shilimkar <santosh.shilimkar@xxxxxx> [130924 08:56]:
> On Tuesday 24 September 2013 11:45 AM, Balaji T K wrote:
> > On Tuesday 24 September 2013 09:10 PM, Tony Lindgren wrote:
> >> * Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx> [130924 01:06]:
> >>> The OMAP GPIO controller HW requires a pin to be configured in GPIO
> >>> input mode in order to operate as an interrupt input. Since drivers
> >>> should not be aware of whether an interrupt pin is also a GPIO or not,
> >>> the HW should be fully configured/enabled as an IRQ if a driver solely
> >>> uses IRQ APIs such as request_irq(), and never calls any GPIO-related
> >>> APIs. As such, add the missing HW setup to the OMAP GPIO controller's
> >>> irq_chip driver.
> >>>
> >>> Since this bypasses the GPIO subsystem we have to ensure that another
> >>> caller won't be able to request the same GPIO pin that is used as an
> >>> IRQ and set its direction as output. Requesting the GPIO and setting
> >>> its direction as input is allowed though.
> >>
> >> Also please mention the regression that this fixes. So far we know
> >> that smsc911x for tobi and igep boards in mainline, and also the
> >
> >> MMC card detect for omap4 boards.
> > Hi Tony,
> >
> > Card detect on omap4 board (sdp and panda) is not based on omap gpio,
> > so I think this fix is not applicable for omap4.
> >
> > Card detect line for SD card goes to power IC on OMAP4 panda and SDP.
> >
> I confused Tony mostly. It was OMAP4 SPI based ethernet which uses the
> GPIO as an interrupt line.
>
> So for Panda, its Ethernet driver and not MMC.

OK :) Thanks for clarifying.

Tony
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