From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 29 Jun 2006 09:24:49 +0000 (-0700)
Subject: [PATCH] genirq: add IRQ_NOREQUEST support
X-Git-Tag: v2.6.18-rc1~376
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6550c775cb5ee94c132d93d84de3bb23f0abf37b;p=linux-2.6

[PATCH] genirq: add IRQ_NOREQUEST support

Enable platforms to disable request_irq() for certain interrupts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/include/linux/irq.h b/include/linux/irq.h
index b2fcf330cf..1df49ec7f8 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -41,6 +41,7 @@
 #endif
 
 #define IRQ_NOPROBE	512	/* IRQ is not valid for probing */
+#define IRQ_NOREQUEST	1024	/* IRQ cannot be requested */
 /**
  * struct hw_interrupt_type - hardware interrupt type descriptor
  *
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 90a944a7fa..cae900a849 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -141,7 +141,7 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
 {
 	struct irqaction *action;
 
-	if (irq >= NR_IRQS)
+	if (irq >= NR_IRQS || irq_desc[irq].status & IRQ_NOREQUEST)
 		return 0;
 
 	action = irq_desc[irq].action;
@@ -356,6 +356,8 @@ int request_irq(unsigned int irq,
 		return -EINVAL;
 	if (irq >= NR_IRQS)
 		return -EINVAL;
+	if (irq_desc[irq].status & IRQ_NOREQUEST)
+		return -EINVAL;
 	if (!handler)
 		return -EINVAL;