Re: [Xenomai-help] PC freezes on call to driver functions

[Jan Kiszka <jan.kiszka@domain.hid>]

Francois Touchard wrote:
> Hello,
> for teaching purposes, I have a very simple driver built with RTDM to catch 
> interrupts generated on the parallel port via a pulse generator. On receipt of a 
> command passed by ioctl, the driver measures the time interval between two 
> interrupts and stores the result (in fact, the sum of n time intervals, n being 
> passed as parameter of ioctl). The result is returned to the user by a read command.
> If I call ioctl immediatly after the open command, the machine freezes and only 
> the reset button is effective. If I insert a print command between open and 
> ioctl, everything works fine.
> I use Xenomai 2.4.9.1 and Linux 2.6.29.5. The processor is a Pentium 4. I attach 
> the sources of the driver and the user application.
> Any hint ? TIA

Switch on at least CONFIG_XENO_OPT_DEBUG_RTDM, but also
CONFIG_IPIPE_DEBUG_CONTEXT can be helpful while writing drivers. Those
will tell you which services you call from the wrong context (here:
rtdm_task_join_nrt from RT context).

Jan

-- 
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux