staging: unisys: visorbus: return EAGAIN when empty

It really isn't an error when you call visorchannel_signalremove and
there isn't anything in the queue. Just means that the IOSP didn't
process anything since the last time you checked. Just inform the
caller that it is empty by returning -EAGAIN.

Signed-off-by: David Kershner <david.kershner@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
David Kershner 2016-11-21 12:15:52 -05:00 committed by Greg Kroah-Hartman
parent 29b2780974
commit 5d295bc3e7

View file

@ -237,8 +237,9 @@ signalremove_inner(struct visorchannel *channel, u32 queue, void *msg)
if (error)
return error;
/* No signals to remove; have caller try again. */
if (sig_hdr.head == sig_hdr.tail)
return -EIO; /* no signals to remove */
return -EAGAIN;
sig_hdr.tail = (sig_hdr.tail + 1) % sig_hdr.max_slots;