Patch "drivers: platform: parse IRQ flags from resources" has been added to the 4.0-stable tree

This is a note to let you know that I've just added the patch titled

drivers: platform: parse IRQ flags from resources

to the 4.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
drivers-platform-parse-irq-flags-from-resources.patch
and it can be found in the queue-4.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Linus Walleij <[email protected]>
Date: Wed, 18 Feb 2015 17:12:18 +0100
Subject: drivers: platform: parse IRQ flags from resources

From: Linus Walleij <[email protected]>

commit 7085a7401ba54e92bbb5aa24d6f428071e18e509 upstream.

This fixes a regression from the net subsystem:
After commit d52fdbb735c36a209f36a628d40ca9185b349ba7 "smc91x: retrieve IRQ and trigger flags in a modern way" a regression would appear on some legacy platforms such as the ARM PXA Zylonite that specify IRQ resources like this:

static struct resource r = {

       .start  = X,
       .end    = X,
       .flags  = IORESOURCE_IRQ | IORESOURCE_IRQ_HIGHEDGE,

};

The previous code would retrieve the resource and parse the high edge setting in the SMC91x driver, a use pattern that means every driver specifying an IRQ flag from a static resource need to parse resource flags and apply them at runtime.

As we switched the code to use IRQ descriptors to retrieve the the trigger type like this:

  irqd_get_trigger_type(irq_get_irq_data(...));

the code would work for new platforms using e.g. device tree as the backing irq descriptor would have its flags properly set, whereas this kind of oldstyle static resources at no point assign the trigger flags to the corresponding IRQ descriptor.

To make the behaviour identical on modern device tree and legacy static platform data platforms, modify platform_get_irq() to assign the trigger flags to the irq descriptor when a client looks up an IRQ from static resources.

---
 drivers/base/platform.c |    9 +++++++++
 1 file changed, 9 insertions(+)

@@ -101,6 +101,15 @@ int platform_get_irq(struct platform_dev
 	}
 
 	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
+	/*
+	 * The resources may pass trigger flags to the irqs that need
+	 * to be set up. It so happens that the trigger flags for
+	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
+	 * settings.
+	 */
+	if (r && r->flags & IORESOURCE_BITS)
+		irqd_set_trigger_type(irq_get_irq_data(r->start),
+				      r->flags & IORESOURCE_BITS);
 
 	return r ? r->start : -ENXIO;
 #endif

Patches currently in stable-queue which might be from [email protected] are

queue-4.0/gpio-mvebu-fix-mask-unmask-managment-per-irq-chip-type.patch queue-4.0/drivers-platform-parse-irq-flags-from-resources.patch