timbgpio: Add support for interrupt triggering on both flanks

From: Richard Röjfors
Date: Wed Jan 20 2010 - 08:23:16 EST


This patch introduces support for triggering interrupts on both rising
and falling edge.

This feature requires version 3 or newer of the IP, a version check is done
when triggering on both edges is requested.

Signed-off-by: Richard Röjfors <richard.rojfors@xxxxxxxxxxxxxx>
---
diff --git a/drivers/gpio/timbgpio.c b/drivers/gpio/timbgpio.c
index a4d344b..471be03 100644
--- a/drivers/gpio/timbgpio.c
+++ b/drivers/gpio/timbgpio.c
@@ -37,6 +37,8 @@
#define TGPIO_ICR 0x14
#define TGPIO_FLR 0x18
#define TGPIO_LVR 0x1c
+#define TGPIO_VER 0x20
+#define TGPIO_BFLR 0x24

struct timbgpio {
void __iomem *membase;
@@ -125,17 +127,23 @@ static int timbgpio_irq_type(unsigned irq, unsigned trigger)
struct timbgpio *tgpio = get_irq_chip_data(irq);
int offset = irq - tgpio->irq_base;
unsigned long flags;
- u32 lvr, flr;
+ u32 lvr, flr, bflr = 0;
+ u32 ver;

if (offset < 0 || offset > tgpio->gpio.ngpio)
return -EINVAL;

+ ver = ioread32(tgpio->membase + TGPIO_VER);
+
spin_lock_irqsave(&tgpio->lock, flags);

lvr = ioread32(tgpio->membase + TGPIO_LVR);
flr = ioread32(tgpio->membase + TGPIO_FLR);
+ if (ver > 2)
+ bflr = ioread32(tgpio->membase + TGPIO_BFLR);

if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
+ bflr &= ~(1 << offset);
flr &= ~(1 << offset);
if (trigger & IRQ_TYPE_LEVEL_HIGH)
lvr |= 1 << offset;
@@ -143,21 +151,27 @@ static int timbgpio_irq_type(unsigned irq, unsigned trigger)
lvr &= ~(1 << offset);
}

- if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
- return -EINVAL;
- else {
+ if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
+ if (ver < 3)
+ return -EINVAL;
+ else {
+ flr |= 1 << offset;
+ bflr |= 1 << offset;
+ }
+ } else {
+ bflr &= ~(1 << offset);
flr |= 1 << offset;
- /* opposite compared to the datasheet, but it mirrors the
- * reality
- */
if (trigger & IRQ_TYPE_EDGE_FALLING)
- lvr |= 1 << offset;
- else
lvr &= ~(1 << offset);
+ else
+ lvr |= 1 << offset;
}

iowrite32(lvr, tgpio->membase + TGPIO_LVR);
iowrite32(flr, tgpio->membase + TGPIO_FLR);
+ if (ver > 2)
+ iowrite32(bflr, tgpio->membase + TGPIO_BFLR);
+
iowrite32(1 << offset, tgpio->membase + TGPIO_ICR);
spin_unlock_irqrestore(&tgpio->lock, flags);


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