From: David Kershner Date: Mon, 21 Nov 2016 17:15:52 +0000 (-0500) Subject: staging: unisys: visorbus: return EAGAIN when empty X-Git-Tag: v5.15~12305^2~112 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5d295bc3e7a6478b690b56994fac87728b88157e;p=platform%2Fkernel%2Flinux-starfive.git 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/unisys/visorbus/visorchannel.c b/drivers/staging/unisys/visorbus/visorchannel.c index 738830e..f51a725 100644 --- a/drivers/staging/unisys/visorbus/visorchannel.c +++ b/drivers/staging/unisys/visorbus/visorchannel.c @@ -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;