[3.13.y.z extended stable] Patch "platform_get_irq: Revert to platform_get_resource if of_irq_get fails" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    platform_get_irq: Revert to platform_get_resource if of_irq_get fails

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.6.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From c047ed014d1a3eeb4351ab22c97815d0ffd8a10b Mon Sep 17 00:00:00 2001
From: Guenter Roeck <linux at roeck-us.net>
Date: Tue, 17 Jun 2014 15:51:02 -0700
Subject: platform_get_irq: Revert to platform_get_resource if of_irq_get fails

commit aff008ad813c7cf3cfe7b532e7ba2c526c136f22 upstream.

Commits 9ec36ca (of/irq: do irq resolution in platform_get_irq)
and ad69674 (of/irq: do irq resolution in platform_get_irq_byname)
change the semantics of platform_get_irq and platform_get_irq_byname
to always rely on devicetree information if devicetree is enabled
and if a devicetree node is attached to the device. The functions
now return an error if the devicetree data does not include interrupt
information, even if the information is available as platform resource
data.

This causes mfd client drivers to fail if the interrupt number is
passed via platform resources. Therefore, if of_irq_get fails, try
platform_get_resource as method of last resort. This restores the
original functionality for drivers depending on platform resources
to get irq information.

Cc: Russell King <linux at arm.linux.org.uk>
Cc: Tony Lindgren <tony at atomide.com>
Cc: Grant Likely <grant.likely at linaro.org>
Cc: Grygorii Strashko <grygorii.strashko at ti.com>
Signed-off-by: Guenter Roeck <linux at roeck-us.net>
Acked-by: Rob Herring <robh at kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/base/platform.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 0d13679..f081b81 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -89,8 +89,13 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
 	return dev->archdata.irqs[num];
 #else
 	struct resource *r;
-	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
-		return of_irq_get(dev->dev.of_node, num);
+	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
+		int ret;
+
+		ret = of_irq_get(dev->dev.of_node, num);
+		if (ret >= 0 || ret == -EPROBE_DEFER)
+			return ret;
+	}

 	r = platform_get_resource(dev, IORESOURCE_IRQ, num);

@@ -133,8 +138,13 @@ int platform_get_irq_byname(struct platform_device *dev, const char *name)
 {
 	struct resource *r;

-	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
-		return of_irq_get_byname(dev->dev.of_node, name);
+	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
+		int ret;
+
+		ret = of_irq_get_byname(dev->dev.of_node, name);
+		if (ret >= 0 || ret == -EPROBE_DEFER)
+			return ret;
+	}

 	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 	return r ? r->start : -ENXIO;
--
1.9.1