Re: Requestirq() = freeze for touchscreendriver

[Kristoffer Ericson <kristoffer.ericson@gmail.com>]

On Fri, 8 Feb 2008 11:57:07 +0900
"Magnus Damm" <magnus.damm@gmail.com> wrote:

> Hi Kristoffer,
> 
> On Feb 7, 2008 10:24 PM, Kristoffer Ericson
> <kristoffer.ericson@gmail.com> wrote:
> > Greetings,
> >
> > These patches are against vanilla 2.6.24, but should apply cleanly to linux-2.6 also. hp6xx_ts_input.patch creates platform_driver for the touchscreen, not much is kept from the old.
> >
> > The booting comes to "waiting to aquire IRQ" and then freezes. So it happens in one of these lines :
> >
> >         printk(KERN_INFO "ts: waiting to request IRQ\n");
> >         error = request_irq(HP680_TS_IRQ, hp680_ts_interrupt,
> >                         IRQF_DISABLED, "HP6XX Touchscreen Driver", pdev);
> 
> You need to track down exactly why the system is freezing. Some recommendations:
> 

I added some printk's into the interrupt and when I startup I end up with a massive loop of those
printk's. Atleast its not frozen :)

However, one would think that it should continue after awhile (with the boot process) but it
keeps looping. The standard interrupt handler should disable  -> enable the interrupt before and after interrupt is done?

> - Figure out how the device is hooked up to the processor. IRQn? IRLn? PINTn?

IRQ3 I believe

> - Verify that you are using the correct IRQ number by calculating it
> from the vector number.

IRQ4 has irq 36 and this is IRQ3 so it should have 35.
IRQ4 = vect(0x680) and IRQ3 = vect(0x660) so should be right.

> - Add a printk in the interrupt handler (hp680_ts_interrupt), see if
> you get any printouts.

massive endless printouts.

> - Is the interrupt shared with someone else? Disable that user and try again.

Only user.

> - Add/modify the irq demuxer in the machvec (.mv_irq_demux) to print
> out all irqs.

This IRQ should be handled by the standard mask_ack/enable/disable system and not by hd64461 ones.

> - Remove as many working devices as possible from your kernel and try again.
> - Check that the interrupt sensing is correct. Is it level triggered?
> Active high? Edge triggered?
> - Make sure the mask and priority bit fields are correct in the
> cpu-specific INTC tables.
> 
> Good luck!
> 

Thx!

> / magnus