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authorJonathan Corbet <corbet@lwn.net>2013-04-30 20:42:33 (GMT)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-05-17 01:08:57 (GMT)
commita7b594b4905828b3bfc36be39d48b5e07a23c8e1 (patch)
tree50a0ceb69d64d652ebb2ac83924d5f85fa930cf2
parentf722406faae2d073cc1d01063d1123c35425939e (diff)
downloadlinux-a7b594b4905828b3bfc36be39d48b5e07a23c8e1.tar.xz
dummy-irq: require the user to specify an IRQ number
Make sure that we let the user know that without specifying IRQ#, dummy-irq driver is useless. Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/misc/dummy-irq.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/misc/dummy-irq.c b/drivers/misc/dummy-irq.c
index 7014167..c37eeed 100644
--- a/drivers/misc/dummy-irq.c
+++ b/drivers/misc/dummy-irq.c
@@ -19,7 +19,7 @@
#include <linux/irq.h>
#include <linux/interrupt.h>
-static int irq;
+static int irq = -1;
static irqreturn_t dummy_interrupt(int irq, void *dev_id)
{
@@ -36,6 +36,10 @@ static irqreturn_t dummy_interrupt(int irq, void *dev_id)
static int __init dummy_irq_init(void)
{
+ if (irq < 0) {
+ printk(KERN_ERR "dummy-irq: no IRQ given. Use irq=N\n");
+ return -EIO;
+ }
if (request_irq(irq, &dummy_interrupt, IRQF_SHARED, "dummy_irq", &irq)) {
printk(KERN_ERR "dummy-irq: cannot register IRQ %d\n", irq);
return -EIO;