Patch "genirq/generic_chip: Add irq_unmap callback" has been added to the 4.8-stable tree

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

genirq/generic_chip: Add irq_unmap callback

to the 4.8-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:
genirq-generic_chip-add-irq_unmap-callback.patch
and it can be found in the queue-4.8 subdirectory.

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

From: Sebastian Frias <[email protected]>
Date: Mon, 1 Aug 2016 16:27:38 +0200
Subject: genirq/generic_chip: Add irq_unmap callback

From: Sebastian Frias <[email protected]>

commit ee26c013cdee0b947e29d6cadfb9ff3341c69ff9 upstream.

Without this patch irq_domain_disassociate() cannot properly release the interrupt. In fact, irq_map_generic_chip() checks a bit on 'gc->installed' but said bit is never cleared, only set.

Commit 088f40b7b027 ("genirq: Generic chip: Add linear irq domain support") added irq_map_generic_chip() function and also stated "This lacks a removal function for now".

This commit provides an implementation of an unmap function that can be called by irq_domain_disassociate().

[ tglx: Made the function static and removed the export as we have neither
a prototype nor a modular user. ]

---
 kernel/irq/generic-chip.c |   21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

@@ -411,8 +411,29 @@ int irq_map_generic_chip(struct irq_doma
 }
 EXPORT_SYMBOL_GPL(irq_map_generic_chip);
 
+static void irq_unmap_generic_chip(struct irq_domain *d, unsigned int virq)
+{
+	struct irq_data *data = irq_domain_get_irq_data(d, virq);
+	struct irq_domain_chip_generic *dgc = d->gc;
+	unsigned int hw_irq = data->hwirq;
+	struct irq_chip_generic *gc;
+	int irq_idx;
+
+	gc = irq_get_domain_generic_chip(d, hw_irq);
+	if (!gc)
+		return;
+
+	irq_idx = hw_irq % dgc->irqs_per_chip;
+
+	clear_bit(irq_idx, &gc->installed);
+	irq_domain_set_info(d, virq, hw_irq, &no_irq_chip, NULL, NULL, NULL,
+			    NULL);
+
+}
+
 struct irq_domain_ops irq_generic_chip_ops = {
 	.map	= irq_map_generic_chip,
+	.unmap  = irq_unmap_generic_chip,
 	.xlate	= irq_domain_xlate_onetwocell,
 };
 EXPORT_SYMBOL_GPL(irq_generic_chip_ops);

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

queue-4.8/genirq-generic_chip-add-irq_unmap-callback.patch