[PATCH v3 6/6] irqchip: crossbar: fix set_wake functionality

From: Grygorii Strashko
Date: Fri Aug 14 2015 - 08:21:54 EST

The TI crossbar doesn't provides any facility to configure the wakeup
sources, but it implements .irq_set_wake() callback:
.irq_set_wake = irq_chip_set_wake_parent

As result, the irq_chip_set_wake_parent() will try to execute
.irq_set_wake() callback for parent IRQ domain, which is TI OMAP wakeupgen,
but TI OMAP wakeupgen has IRQCHIP_SKIP_SET_WAKE flag set and do not
implement .irq_set_wake() callback. Thus, irq_chip_set_wake_parent() will
fail with -ENOSYS.

In case of TI OMAP DRA7 the issue reproduced with following
ARM GIC<-OMAP wakeupgen<-TI CBAR<-GPIO<-GPIO pcf857x<-gpio_key

gpio_key is wakeup source

Failure is reproduced during suspend/resume to RAM:
- gpio_keys_suspend
+ enable_irq_wake
+ pcf857x_irq_set_wake
+ omap_gpio_wake_enable
+ TI CBAR irq_chip_set_wake_parent
+ OMAP wakeupgen has no .irq_set_wake() and
-ENOSYS will be returned

- gpio_keys_resume
+ disable_irq_wake
+ irq_set_irq_wake
+ WARN(1, "Unbalanced IRQ %d wake disable\n", irq);

Hence, fix it by adding IRQCHIP_SKIP_SET_WAKE flag to TI Crossbar and
drop .irq_set_wake() at the same time.

Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
drivers/irqchip/irq-crossbar.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-crossbar.c b/drivers/irqchip/irq-crossbar.c
index f5a72cc..c12bb93 100644
--- a/drivers/irqchip/irq-crossbar.c
+++ b/drivers/irqchip/irq-crossbar.c
@@ -68,9 +68,9 @@ static struct irq_chip crossbar_chip = {
.irq_mask = irq_chip_mask_parent,
.irq_unmask = irq_chip_unmask_parent,
.irq_retrigger = irq_chip_retrigger_hierarchy,
- .irq_set_wake = irq_chip_set_wake_parent,
.irq_set_type = irq_chip_set_type_parent,
.irq_set_affinity = irq_chip_set_affinity_parent,

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