genirq: Mirror irq trigger type bits in irq_data.state

That's the data structure chip functions get provided. Also allow them
to signal the core code that they updated the flags in irq_data.state
by returning IRQ_SET_MASK_OK_NOCOPY. The default is unchanged.

The type bits should be accessed via:

val = irqd_get_trigger_type(irqdata);
and
irqd_set_trigger_type(irqdata, val);

Coders who access them directly will be tracked down and slapped with
stinking trouts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 8da1782..be73c0a 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -46,7 +46,9 @@
 #define IRQ_TYPE_EDGE_BOTH (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)
 #define IRQ_TYPE_LEVEL_HIGH	0x00000004	/* Level high type */
 #define IRQ_TYPE_LEVEL_LOW	0x00000008	/* Level low type */
+#define IRQ_TYPE_LEVEL_MASK	(IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)
 #define IRQ_TYPE_SENSE_MASK	0x0000000f	/* Mask of the above */
+
 #define IRQ_TYPE_PROBE		0x00000010	/* Probing in progress */
 
 /* Internal flags */
@@ -131,17 +133,20 @@
 /*
  * Bit masks for irq_data.state
  *
+ * IRQD_TRIGGER_MASK		- Mask for the trigger type bits
  * IRQD_SETAFFINITY_PENDING	- Affinity setting is pending
  * IRQD_NO_BALANCING		- Balancing disabled for this IRQ
  * IRQD_PER_CPU			- Interrupt is per cpu
  * IRQD_AFFINITY_SET		- Interrupt affinity was set
+ * IRQD_LEVEL			- Interrupt is level triggered
  */
 enum {
-	/* Bit 0 - 7 reserved for TYPE will use later */
+	IRQD_TRIGGER_MASK		= 0xf,
 	IRQD_SETAFFINITY_PENDING	= (1 <<  8),
 	IRQD_NO_BALANCING		= (1 << 10),
 	IRQD_PER_CPU			= (1 << 11),
 	IRQD_AFFINITY_SET		= (1 << 12),
+	IRQD_LEVEL			= (1 << 13),
 };
 
 static inline bool irqd_is_setaffinity_pending(struct irq_data *d)
@@ -164,6 +169,25 @@
 	return d->state_use_accessors & IRQD_AFFINITY_SET;
 }
 
+static inline u32 irqd_get_trigger_type(struct irq_data *d)
+{
+	return d->state_use_accessors & IRQD_TRIGGER_MASK;
+}
+
+/*
+ * Must only be called inside irq_chip.irq_set_type() functions.
+ */
+static inline void irqd_set_trigger_type(struct irq_data *d, u32 type)
+{
+	d->state_use_accessors &= ~IRQD_TRIGGER_MASK;
+	d->state_use_accessors |= type & IRQD_TRIGGER_MASK;
+}
+
+static inline bool irqd_is_level_type(struct irq_data *d)
+{
+	return d->state_use_accessors & IRQD_LEVEL;
+}
+
 /**
  * struct irq_chip - hardware interrupt chip descriptor
  *