gpio: omap: Fix regression for MPUIO interrupts

At some point with all the GPIO clean-up we've broken the
MPUIO interrupts. Those are just a little bit different from
the GPIO interrupts, so we can fix it up just by setting
different irqchip functions for it. And then we can just
remove all old code trying to do the same.

Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Javier Martinez Canillas <javier@dowhile0.org>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-omap.c

@@ -1054,38 +1054,8 @@ static void omap_gpio_mod_init(struct gpio_bank *bank)
 		dev_err(bank->dev, "Could not get gpio dbck\n");
 }
 
-static void
-omap_mpuio_alloc_gc(struct gpio_bank *bank, unsigned int irq_start,
-		    unsigned int num)
-{
-	struct irq_chip_generic *gc;
-	struct irq_chip_type *ct;
-
-	gc = irq_alloc_generic_chip("MPUIO", 1, irq_start, bank->base,
-				    handle_simple_irq);
-	if (!gc) {
-		dev_err(bank->dev, "Memory alloc failed for gc\n");
-		return;
-	}
-
-	ct = gc->chip_types;
-
-	/* NOTE: No ack required, reading IRQ status clears it. */
-	ct->chip.irq_mask = irq_gc_mask_set_bit;
-	ct->chip.irq_unmask = irq_gc_mask_clr_bit;
-	ct->chip.irq_set_type = omap_gpio_irq_type;
-
-	if (bank->regs->wkup_en)
-		ct->chip.irq_set_wake = omap_gpio_wake_enable;
-
-	ct->regs.mask = OMAP_MPUIO_GPIO_INT / bank->stride;
-	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
-			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
-}
-
 static int omap_gpio_chip_init(struct gpio_bank *bank, struct irq_chip *irqc)
 {
-	int j;
 	static int gpio;
 	int irq_base = 0;
 	int ret;
@@ -1132,6 +1102,15 @@ static int omap_gpio_chip_init(struct gpio_bank *bank, struct irq_chip *irqc)
 	}
 #endif
 
+	/* MPUIO is a bit different, reading IRQ status clears it */
+	if (bank->is_mpuio) {
+		irqc->irq_ack = dummy_irq_chip.irq_ack;
+		irqc->irq_mask = irq_gc_mask_set_bit;
+		irqc->irq_unmask = irq_gc_mask_clr_bit;
+		if (!bank->regs->wkup_en)
+			irqc->irq_set_wake = NULL;
+	}
+
 	ret = gpiochip_irqchip_add(&bank->chip, irqc,
 				   irq_base, omap_gpio_irq_handler,
 				   IRQ_TYPE_NONE);
@@ -1145,15 +1124,6 @@ static int omap_gpio_chip_init(struct gpio_bank *bank, struct irq_chip *irqc)
 	gpiochip_set_chained_irqchip(&bank->chip, irqc,
 				     bank->irq, omap_gpio_irq_handler);
 
-	for (j = 0; j < bank->width; j++) {
-		int irq = irq_find_mapping(bank->chip.irqdomain, j);
-		if (bank->is_mpuio) {
-			omap_mpuio_alloc_gc(bank, irq, bank->width);
-			irq_set_chip_and_handler(irq, NULL, NULL);
-			set_irq_flags(irq, 0);
-		}
-	}
-
 	return 0;
 }