gpio: unmap gpio irqs properly

When using the irqchip helper inside the gpiolib, make sure
the IRQs are unmapped/disposed before the irqdomain is removed
as part of removing the gpiochip.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f41cb4f..761013f 100644 (file)
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1399,8 +1399,18 @@ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
        return 0;
 }
 
+static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
+{
+#ifdef CONFIG_ARM
+       set_irq_flags(irq, 0);
+#endif
+       irq_set_chip_and_handler(irq, NULL, NULL);
+       irq_set_chip_data(irq, NULL);
+}
+
 static const struct irq_domain_ops gpiochip_domain_ops = {
        .map    = gpiochip_irq_map,
+       .unmap  = gpiochip_irq_unmap,
        /* Virtually all GPIO irqchips are twocell:ed */
        .xlate  = irq_domain_xlate_twocell,
 };
@@ -1438,8 +1448,14 @@ static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
  */
 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
 {
-       if (gpiochip->irqdomain)
+       unsigned int offset;
+
+       /* Remove all IRQ mappings and delete the domain */
+       if (gpiochip->irqdomain) {
+               for (offset = 0; offset < gpiochip->ngpio; offset++)
+                       irq_dispose_mapping(gpiochip->irq_base + offset);
                irq_domain_remove(gpiochip->irqdomain);
+       }
 
        if (gpiochip->irqchip) {
                gpiochip->irqchip->irq_request_resources = NULL;
@@ -1467,7 +1483,8 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
  * translation. The gpiochip will need to be initialized and registered
  * before calling this function.
  *
- * This function will handle two cell:ed simple IRQs. Everything else
+ * This function will handle two cell:ed simple IRQs and assumes all
+ * the pins on the gpiochip can generate a unique IRQ. Everything else
  * need to be open coded.
  */
 int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
@@ -1478,6 +1495,7 @@ int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
 {
        struct device_node *of_node;
        unsigned int offset;
+       unsigned irq_base = 0;
 
        if (!gpiochip || !irqchip)
                return -EINVAL;
@@ -1514,8 +1532,15 @@ int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
         * any gpiochip calls. If the first_irq was zero, this is
         * necessary to allocate descriptors for all IRQs.
         */
-       for (offset = 0; offset < gpiochip->ngpio; offset++)
-               irq_create_mapping(gpiochip->irqdomain, offset);
+       for (offset = 0; offset < gpiochip->ngpio; offset++) {
+               irq_base = irq_create_mapping(gpiochip->irqdomain, offset);
+               if (offset == 0)
+                       /*
+                        * Store the base into the gpiochip to be used when
+                        * unmapping the irqs.
+                        */
+                       gpiochip->irq_base = irq_base;
+       }
 
        return 0;
 }

diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index c1c5c23..1827b43 100644 (file)
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -107,6 +107,7 @@ struct gpio_chip {
         */
        struct irq_chip         *irqchip;
        struct irq_domain       *irqdomain;
+       unsigned int            irq_base;
        irq_flow_handler_t      irq_handler;
        unsigned int            irq_default_type;
 #endif