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>

1 files changed, 29 insertions, 4 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f41cb4f3d715..761013f8b82f 100644
--- 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;
 }