[ltp] Thinkpad x61 Tablet (irq 20: nobody cared)

[Rob Kendrick]

Hendrik-Jan Heins top-posted:
> So far I even have most Thinppad buttons working too (so also wireless
> on / off, bluetooth on/off,

All of these work out of the box for me on Ubuntu 7.04.  I did, however,
patch the thinkpad-keys daemon to only check status once every half
second rather than every 50ms to reduce CPU wakes.  Apparently, in newer
kernels the ibm-acpi stuff renders daemons like thinkpad-keys tpd redundant.

> suspend to ram, sleep and auto suspend to
> ram on closing the lid.

I only have suspend to RAM working with init=/bin/bash.  I suspect a
module is causing it to fail (it never turns off - it just remains on
blinking the moon LED.)  I have yet to manage to gather the patience to
work out which module it is by removing them one by one and rebooting
everytime.  Suggestions welcome.  (I've tried removing ALSA, the
graphics, and the Wi Fi-related drivers.)

> The only things I can't seem to get to work at the moment are the
> brightness buttons and the volume up/down buttons.

My volume buttons work perfectly with thinkpad-keys.  I can change the
brightness manually with poking in /proc.  I suspect configuration
faults somewhere in acpi-support.

> And I'd also REALLY like to have the "page forward/"page back" buttons
> to work in the browser, but I have no idea how.

They generate keycodes 0xe9 and 0xe0 respectively according to the GNOME
keyboard shortcuts config applet, so they can certainly be detected.
The thing you have to do is make your browser respond to those
keypresses.  I don't believe GNOME or KDE have any infrastructure for
supporting such keys, but perhaps a Firefox extension could be written?

> As for irqpoll; see:
> http://www.mjmwired.net/kernel/Documentation/kernel-parameters.txt
> 
> <snip>
> irqpoll		[HW]
> 802				When an interrupt is not handled search all handlers
> 803				for it. Also check all handlers each timer
> 804				interrupt. Intended to get systems with badly broken
> 805				firmware running.
> </snip>
> 
> 
> http://sourceforge.net/tracker/?atid=447449&group_id=42302&func=browse
> I can't find the exact bug anymore,
> but there are a couple of them in there that are related to this issue.
> When I went tthrough the buglist, I tried varieous options mentioned
> there, and it turned out that the unstable behaviour was related to
> the irqpoll option for me.

I'm certainly not seeing any of these problems that are mentioned - the
unhandled IRQ appears to only occur once, at boot.  And all of my USB
sockets work regardless of the option being present or not.

B.