From: Ian Abbott <abbotti@mev.co.uk>
Date: Fri, 25 Jul 2014 17:07:07 +0000 (+0100)
Subject: staging: comedi: amplc_dio200_common: prevent extra free_irq()
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=a386149fb2bad23b5c6123894049ce3392bf76b5;p=deliverable%2Flinux.git

staging: comedi: amplc_dio200_common: prevent extra free_irq()

`dio200_detach()` in "amplc_dio200.c" calls
`amplc_dio200_common_detach()` in "amplc_dio200_common.c", followed by
`comedi_legacy_detach()` in "../drivers.c".  Both of those functions
call `free_irq()` if `dev->irq` is non-zero.  The second call produces a
warning message because the handler has already been freed.  Prevent
that by setting `dev->irq = 0` in `amplc_dio200_common_detach()`.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/staging/comedi/drivers/amplc_dio200_common.c b/drivers/staging/comedi/drivers/amplc_dio200_common.c
index 78700e8185ed..3592e58c57d5 100644
--- a/drivers/staging/comedi/drivers/amplc_dio200_common.c
+++ b/drivers/staging/comedi/drivers/amplc_dio200_common.c
@@ -1202,8 +1202,10 @@ void amplc_dio200_common_detach(struct comedi_device *dev)
 
 	if (!thisboard || !devpriv)
 		return;
-	if (dev->irq)
+	if (dev->irq) {
 		free_irq(dev->irq, dev);
+		dev->irq = 0;
+	}
 }
 EXPORT_SYMBOL_GPL(amplc_dio200_common_detach);