genirq: record trigger type
Genirq hasn't previously recorded the trigger type used by any given IRQ,
although some irq_chip support has done so. That data can be useful when
troubleshooting. This patch records it in the relevant irq_desc.status
bits, and improves consistency between the two driver-visible calls
affected:
- Make set_irq_type() usage match request_irq() usage:
* IRQ_TYPE_NONE should be a NOP; succeed, so irq_chip methods
won't have to handle that case any more (many do it wrong).
* IRQ_TYPE_PROBE is ignored; any buggy out-of-tree callers
might need to switch over to the real IRQ probing code.
* emit the same diagnostics (from shared utility code)
- Their kerneldoc now reflects usage:
* request_irq() flags include IRQF_TRIGGER_* to specify
active edge(s)/level ... docs previously omitted that
* set_irq_type() is declared in <linux/irq.h> so callers
should use the (bit-equivalent) IRQ_TYPE_* symbols there
Also: adds a warning about shared IRQs that don't end up using the
requested trigger mode; and fix an unrelated "sparse" warning.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index d663338..5203a59 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -111,9 +111,9 @@
EXPORT_SYMBOL(set_irq_chip);
/**
- * set_irq_type - set the irq type for an irq
+ * set_irq_type - set the irq trigger type for an irq
* @irq: irq number
- * @type: interrupt type - see include/linux/interrupt.h
+ * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
*/
int set_irq_type(unsigned int irq, unsigned int type)
{
@@ -127,11 +127,12 @@
}
desc = irq_desc + irq;
- if (desc->chip->set_type) {
- spin_lock_irqsave(&desc->lock, flags);
- ret = desc->chip->set_type(irq, type);
- spin_unlock_irqrestore(&desc->lock, flags);
- }
+ if (type == IRQ_TYPE_NONE)
+ return 0;
+
+ spin_lock_irqsave(&desc->lock, flags);
+ ret = __irq_set_trigger(desc, irq, flags);
+ spin_unlock_irqrestore(&desc->lock, flags);
return ret;
}
EXPORT_SYMBOL(set_irq_type);