From 77e7c200f37536e05f714bcebc34f58aba9eabfc Mon Sep 17 00:00:00 2001
From: H Hartley Sweeten <hsweeten@visionengravers.com>
Date: Mon, 5 Oct 2015 14:23:07 -0700
Subject: [PATCH] staging: comedi: quatech_daqp_cs: handle shared interrupt
This is a PCMCIA driver and interrupts are always shared. Detect if
the hardware did not produce the interrupt and return IRQ_NONE so
that other drivers might handle it.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/staging/comedi/drivers/quatech_daqp_cs.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/staging/comedi/drivers/quatech_daqp_cs.c b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
index 7432e5761539..c44e7ec19e47 100644
--- a/drivers/staging/comedi/drivers/quatech_daqp_cs.c
+++ b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
@@ -214,6 +214,9 @@ static irqreturn_t daqp_interrupt(int irq, void *dev_id)
return IRQ_NONE;
status = inb(dev->iobase + DAQP_STATUS_REG);
+ if (!(status & DAQP_STATUS_EVENTS))
+ return IRQ_NONE;
+
while (!(status & DAQP_STATUS_FIFO_EMPTY)) {
unsigned short data;
--
2.34.1