MIPS: EMMA2RH: Use handle_edge_irq() handler for GPIO interrupts

EMMA's GPIO interrupts are latched by GPIO interrupt status register.
In this case, we're encouraged to use handle_edge_irq() handler.

The following changes are made along with replacing set_irq_chip() with
set_irq_chip_and_handler_name(,,handle_edge_irq,"edge"):

* Fix emma2rh_gpio_irq_ack not to disable interrupts

  With handle_edge_irq(), we're not expected to disable interrupts
  when chip->ack is served, so fix it accordingly.  We also add a new
  emma2rh_gpio_irq_mask_ack() for chip->mask_ack operation, instead.

* Remove emma2rh_gpio_irq_end(), as chip->end is no longer served.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/emma/markeins/irq.c

@@ -149,37 +149,28 @@ static void emma2rh_gpio_irq_disable(unsigned int irq)
 
 static void emma2rh_gpio_irq_ack(unsigned int irq)
 {
-	u32 reg;
-
 	irq -= EMMA2RH_GPIO_IRQ_BASE;
 	emma2rh_out32(EMMA2RH_GPIO_INT_ST, ~(1 << irq));
-
-	reg = emma2rh_in32(EMMA2RH_GPIO_INT_MASK);
-	reg &= ~(1 << irq);
-	emma2rh_out32(EMMA2RH_GPIO_INT_MASK, reg);
 }
 
-static void emma2rh_gpio_irq_end(unsigned int irq)
+static void emma2rh_gpio_irq_mask_ack(unsigned int irq)
 {
 	u32 reg;
 
-	if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
-
-		irq -= EMMA2RH_GPIO_IRQ_BASE;
+	irq -= EMMA2RH_GPIO_IRQ_BASE;
+	emma2rh_out32(EMMA2RH_GPIO_INT_ST, ~(1 << irq));
 
-		reg = emma2rh_in32(EMMA2RH_GPIO_INT_MASK);
-		reg |= 1 << irq;
-		emma2rh_out32(EMMA2RH_GPIO_INT_MASK, reg);
-	}
+	reg = emma2rh_in32(EMMA2RH_GPIO_INT_MASK);
+	reg &= ~(1 << irq);
+	emma2rh_out32(EMMA2RH_GPIO_INT_MASK, reg);
 }
 
 struct irq_chip emma2rh_gpio_irq_controller = {
 	.name = "emma2rh_gpio_irq",
 	.ack = emma2rh_gpio_irq_ack,
 	.mask = emma2rh_gpio_irq_disable,
-	.mask_ack = emma2rh_gpio_irq_ack,
+	.mask_ack = emma2rh_gpio_irq_mask_ack,
 	.unmask = emma2rh_gpio_irq_enable,
-	.end = emma2rh_gpio_irq_end,
 };
 
 void emma2rh_gpio_irq_init(void)
@@ -187,8 +178,9 @@ void emma2rh_gpio_irq_init(void)
 	u32 i;
 
 	for (i = 0; i < NUM_EMMA2RH_IRQ_GPIO; i++)
-		set_irq_chip(EMMA2RH_GPIO_IRQ_BASE + i,
-			     &emma2rh_gpio_irq_controller);
+		set_irq_chip_and_handler_name(EMMA2RH_GPIO_IRQ_BASE + i,
+					      &emma2rh_gpio_irq_controller,
+					      handle_edge_irq, "edge");
 }
 
 static struct irqaction irq_cascade = {