gpio irqs broken on imx27 with dt

gpio irqs broken on imx27 with dt

[Uwe Kleine-König]

Hello,

I experience problems on using gpio irqs on an imx27 based machine
booting with dt.

I think one problem is:

        if (mxc_gpio_hwtype == IMX21_GPIO) {
                /* setup one handler for all GPIO interrupts */
                if (pdev->id == 0)
                        irq_set_chained_handler(port->irq,
                                                mx2_gpio_irq_handler);
	} ...

because the inner if doesn't trigger as dt-created gpio devices have all
pdev->id == -1.

I havn't looked deeper into it yet, but I think another problem is that
gpios don't start at 0 and so the usual

	#define OTG_PHY_CS_GPIO (GPIO_PORTB + 23)

doesn't work either (which might be expected, but doesn't necessarily
needs to fail?!). (You could argue I shouldn't hardcode gpio numbers any
more, but as not all device drivers are oftree aware yet I need to get
of the ground somehow.)

I'm leaving for the weekend now, so just wanted you to inform that there
is a problem. Shawn, maybe you have an idea?

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

gpio irqs broken on imx27 with dt

[Dong Aisheng]

On Fri, Apr 27, 2012 at 02:50:48PM +0200, Uwe Kleine-K?nig wrote:
> Hello,
> 
> I experience problems on using gpio irqs on an imx27 based machine
> booting with dt.
> 
> I think one problem is:
> 
>         if (mxc_gpio_hwtype == IMX21_GPIO) {
>                 /* setup one handler for all GPIO interrupts */
>                 if (pdev->id == 0)
>                         irq_set_chained_handler(port->irq,
>                                                 mx2_gpio_irq_handler);
> 	} ...
> 
> because the inner if doesn't trigger as dt-created gpio devices have all
> pdev->id == -1.
> 
> I havn't looked deeper into it yet, but I think another problem is that
> gpios don't start at 0 and so the usual
> 
Yes, for dt, gpio base is allocated dynamically.
See gpiochip_find_base.

> 	#define OTG_PHY_CS_GPIO (GPIO_PORTB + 23)
> 
> doesn't work either (which might be expected, but doesn't necessarily
> needs to fail?!). (You could argue I shouldn't hardcode gpio numbers any
> more, but as not all device drivers are oftree aware yet I need to get
> of the ground somehow.)
> 
I guess dt user never know a pin's gpio number since they're allocated
dynamically. User should only parse it from device tree then it can be safe
to use.

Regards
Dong Aisheng

gpio irqs broken on imx27 with dt

[Fabio Estevam]

Uwe,

2012/4/27 Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de>:
> Hello,
>
> I experience problems on using gpio irqs on an imx27 based machine
> booting with dt.

Currently there is no pinctrl driver for mx27.

What you can do as a temporary workaround is to do the same as mx51 or mx53:

config MACH_IMX51_DT
	bool "Support i.MX51 platforms from device tree"
	select SOC_IMX51
	select MACH_MX51_BABBAGE
	select USE_OF
	help
	  Include support for Freescale i.MX51 based platforms
	  using the device tree for discovery

MACH_IMX51_DT currently selects MACH_MX51_BABBAGE so that the IOMUX
infrastructure can be used.

Regards,

Fabio Estevam

gpio irqs broken on imx27 with dt

[Sascha Hauer]

On Fri, Apr 27, 2012 at 02:50:48PM +0200, Uwe Kleine-K?nig wrote:
> Hello,
> 
> I experience problems on using gpio irqs on an imx27 based machine
> booting with dt.
> 
> I think one problem is:
> 
>         if (mxc_gpio_hwtype == IMX21_GPIO) {
>                 /* setup one handler for all GPIO interrupts */
>                 if (pdev->id == 0)
>                         irq_set_chained_handler(port->irq,
>                                                 mx2_gpio_irq_handler);
> 	} ...
> 
> because the inner if doesn't trigger as dt-created gpio devices have all
> pdev->id == -1.

How about

	static int once = 0;

	if (mxc_gpio_hwtype == IMX21_GPIO) {
		/* setup one handler for all GPIO interrupts */
		if (!once) {
			irq_set_chained_handler(port->irq,
						mx2_gpio_irq_handler);
			once = 1;
		}

Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

gpio irqs broken on imx27 with dt

[Uwe Kleine-König]

Hello,

On Fri, Apr 27, 2012 at 11:50:45PM +0200, Sascha Hauer wrote:
> On Fri, Apr 27, 2012 at 02:50:48PM +0200, Uwe Kleine-K?nig wrote:
> > I experience problems on using gpio irqs on an imx27 based machine
> > booting with dt.
> > 
> > I think one problem is:
> > 
> >         if (mxc_gpio_hwtype == IMX21_GPIO) {
> >                 /* setup one handler for all GPIO interrupts */
> >                 if (pdev->id == 0)
> >                         irq_set_chained_handler(port->irq,
> >                                                 mx2_gpio_irq_handler);
> > 	} ...
> > 
> > because the inner if doesn't trigger as dt-created gpio devices have all
> > pdev->id == -1.
> 
> How about
> 
> 	static int once = 0;
> 
> 	if (mxc_gpio_hwtype == IMX21_GPIO) {
> 		/* setup one handler for all GPIO interrupts */
> 		if (!once) {
> 			irq_set_chained_handler(port->irq,
> 						mx2_gpio_irq_handler);
> 			once = 1;
> 		}
I did exactly this, but it didn't cure all my problems. And it's ugly
(not much more than testing pdev->id == 0 though). I'm not sure it's
worth to clean that up. (e.g. use a single device for the imx21 type
handling all ports vs. one device per port for the latter types. This
way each device would handle one and only one irq.)

Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |