genirq: Restore trigger settings in irq_modify_status()

irq_modify_status starts by clearing the trigger settings from
irq_data before applying the new settings, but doesn't restore them,
leaving them to IRQ_TYPE_NONE.

That's pretty confusing to the potential request_irq() that could
follow. Instead, snapshot the settings before clearing them, and restore
them if the irq_modify_status() invocation was not changing the trigger.

Fixes: 1e2a7d7849 ("irqdomain: Don't set type when mapping an IRQ")
Reported-and-tested-by: jeffy <jeffy.chen@rock-chips.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170818095345.12378-1-marc.zyngier@arm.com
This commit is contained in:
Marc Zyngier 2017-08-18 10:53:45 +01:00 committed by Thomas Gleixner
parent 7374bfb82e
commit e8f241893d

View File

@ -1000,7 +1000,7 @@ EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
{
unsigned long flags;
unsigned long flags, trigger, tmp;
struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
if (!desc)
@ -1014,6 +1014,8 @@ void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
irq_settings_clr_and_set(desc, clr, set);
trigger = irqd_get_trigger_type(&desc->irq_data);
irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
if (irq_settings_has_no_balance_set(desc))
@ -1025,7 +1027,11 @@ void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
if (irq_settings_is_level(desc))
irqd_set(&desc->irq_data, IRQD_LEVEL);
irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
tmp = irq_settings_get_trigger_mask(desc);
if (tmp != IRQ_TYPE_NONE)
trigger = tmp;
irqd_set(&desc->irq_data, trigger);
irq_put_desc_unlock(desc, flags);
}