Change hpilo open and close logic to spin for 10usec between checking device,
rather than every usec.

Because the loop is coded to take up to 10ms, it seemed prudent to
increase the interval between polling the device, to reduce the load on
the system and allow more other work to happen.
Signed-off-by: NDavid Altobelli <david.altobelli@hp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The device can take a while to respond to an open/close request, so
increase the time kernel will wait for response (1 ms to 10ms).

Also, properly clean up a channel on a failed open, by calling the channel
close routine.  Just freeing the memory isn't sufficient, the device needs
to be informed that the channel is no longer open, and the device memory
cleared of references to freed dma buffer.
Signed-off-by: NDavid Altobelli <david.altobelli@hp.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A driver for the HP iLO/iLO2 management processor, which allows userspace
programs to query the management processor.  Programs can open a channel
to the device (/dev/hpilo/dXccbN), and use this to send/receive queries.  
The O_EXCL open flag is used to indicate that a particular channel cannot
be shared between processes.  This driver will replace various packages
HP has shipped, including hprsm and hp-ilo.
Signed-off-by: NDavid Altobelli <david.altobelli@hp.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>