s390/cio: make fmt1 channel path descriptor optional
commit0b601373778c770d7536b1d1761c3b2c06e4eb24
authorSebastian Ott <sebott@linux.vnet.ibm.com>
Thu, 14 Jul 2016 09:30:37 +0000 (14 11:30 +0200)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Fri, 15 Jul 2016 12:31:59 +0000 (15 14:31 +0200)
tree5f7003c8e117db1bffacaa3102352e422cfb8f48
parent6228c2a51edccf3e01fc4db065aac91b4cafdc76
s390/cio: make fmt1 channel path descriptor optional

Not all machines / hypervisors support the chsc commands to fetch
the fmt1 descriptor. When these commands fail the channel path would
currently not be available to linux.

Since users of these descriptors can already deal with invalid data
make fetching it optional. The only data that is mandatory for us is
the fmt0 channel path descriptor.

Also make the return code for missing facilities in
chsc_get_channel_measurement_chars consistent to other functions.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
drivers/s390/cio/chp.c
drivers/s390/cio/chsc.c