[PATCH] kernel: irq: Call irq_chip->irq_mask in irq_disable

[PATCH] kernel: irq: Call irq_chip->irq_mask in irq_disable

[Laxman Dewangan]

From: sreenivasulu velpula <svelpula@nvidia.com>

If interrupt driver has implemented the irq_mask/irq_unmask
callbacks for disable/enable interrupt then call these APIs
from irq_disable/irq_enable.

Currently, on irq_disable(), it just look for the callback
irq_disable() implemented by chip interrupt driver not the
irq_mask().

Add check for the valid callback of irq_mask() and if it is
there then call it from irq_disable.

This is based on change done by:
	sreenivasulu velpula <svelpula@nvidia.com>

Signed-off-by: sreenivasulu velpula <svelpula@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
---
 kernel/irq/chip.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index a3bb14f..b6efb92 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -232,6 +232,9 @@ void irq_disable(struct irq_desc *desc)
 	if (desc->irq_data.chip->irq_disable) {
 		desc->irq_data.chip->irq_disable(&desc->irq_data);
 		irq_state_set_masked(desc);
+	} else if (desc->irq_data.chip->irq_mask) {
+		desc->irq_data.chip->irq_mask(&desc->irq_data);
+		irq_state_set_masked(desc);
 	}
 }
 
-- 
1.7.1.1

Re: [PATCH] kernel: irq: Call irq_chip->irq_mask in irq_disable

[Thomas Gleixner]

On Tue, 9 Jul 2013, Laxman Dewangan wrote:

> From: sreenivasulu velpula <svelpula@nvidia.com>
> 
> If interrupt driver has implemented the irq_mask/irq_unmask
> callbacks for disable/enable interrupt then call these APIs
> from irq_disable/irq_enable.
> 
> Currently, on irq_disable(), it just look for the callback
> irq_disable() implemented by chip interrupt driver not the
> irq_mask().
> 
> Add check for the valid callback of irq_mask() and if it is
> there then call it from irq_disable.

No. That changes the semantics of lazy irq disable and breaks
suspend/resume because we rely on NOT masking interrupts to detect a
wakeup.

The irq_disable() merily marks the interrupt disabled and only touches
the hardware when the interrupt controller provides an explicit
irq_disable() callback.

Thanks,

	tglx