[ltp] T42: irda not working after resuming from suspend to RAM

[David de Hoog]

Greetings

I'm having exactly the same issue on my T42 2378-JZM (2.6.11 patched
with mppe support, in a Debian Sarge system).

When the machine boots for the first time IrDA works nicely. However,
running `setserial /dev/ttyS1` reveals "device type: undefined", which
is different to "device type: unknown" - but allows the device to
function. Additionally, the output of `ifconfig irda0` does not include
a hardware address, it is "00:00:00:00". That said, it works - I can
detect the presence of my Nokia 7250i with `irdadump` and exchange
information with the phone using gammu and wammu. 

As soon as the laptop is suspended (to RAM) either by power management
or through my intervention, the IrDA device stops receiving. If I run
irdadump and wave the phone nearby, there is no signal being received. I
can unload and re-load all the relevant kernel modules and there is no
change. The T42 is still aware of its own IrDA port, as it appears in
the `irdadump` listing. `dmesg` does not indicate anything of concern,
and believes it is functioning well.

I've had a quick google and a good long mess around with the kernel
modules to no avail. I'm going to check to see if suspend to disk causes
the same problem. The only other option I can see is to try and unload
the IrDA modules from the kernel before the system suspends to RAM, and
re-loads them on waking up. I'll have a dig through the contents of
my /etc/acpi/ directory shortly.

I'm not convinced that my TP supports the FIR driver, because all my
attempts to load the nsc_ircc module have met with failure. I have seen
writings elsewhere indicating that (at least for the X series TPs) a
kernel patch is required for the 2.6.11 tree in order to use the
nsc_ircc module. Additionally, I have no idea whether my phone supports
FIR, but it works nicely with SIR.

Does anyone have any other ideas or experience to share ?

Cheers
-- 
David de Hoog <dehood01@student.uwa.edu.au>