From 5d295bc3e7a6478b690b56994fac87728b88157e Mon Sep 17 00:00:00 2001 From: David Kershner <david.kershner@unisys.com> Date: Mon, 21 Nov 2016 12:15:52 -0500 Subject: [PATCH] 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> --- drivers/staging/unisys/visorbus/visorchannel.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/staging/unisys/visorbus/visorchannel.c b/drivers/staging/unisys/visorbus/visorchannel.c index 738830e3be94e..f51a7258bef07 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; -- 2.30.2