gpio: max732x: Rewrite IRQ code to use irq_domain API

Signed-off-by: Semen Protsenko <semen.protsenko@globallogic.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

2 files changed, 66 insertions, 35 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 192f97396d12..d24492c59bf9 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -528,6 +528,7 @@ config GPIO_MAX7300
 config GPIO_MAX732X
         tristate "MAX7319, MAX7320-7327 I2C Port Expanders"
         depends on I2C
+        select IRQ_DOMAIN
         help
           Say yes here to support the MAX7319, MAX7320-7327 series of I2C
           Port Expanders. Each IO port on these chips has a fixed role of
diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index a642f780901d..f8f3e8081a89 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -19,6 +19,7 @@
 #include <linux/gpio.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/i2c.h>
 #include <linux/i2c/max732x.h>
 #include <linux/of.h>
@@ -149,13 +150,14 @@ struct max732x_chip {
         uint8_t         reg_out[2];
 
 #ifdef CONFIG_GPIO_MAX732X_IRQ
-        struct mutex    irq_lock;
-        int             irq_base;
-        uint8_t         irq_mask;
-        uint8_t         irq_mask_cur;
-        uint8_t         irq_trig_raise;
-        uint8_t         irq_trig_fall;
-        uint8_t         irq_features;
+        struct irq_domain       *irq_domain;
+        struct mutex            irq_lock;
+        int                     irq_base;
+        uint8_t                 irq_mask;
+        uint8_t                 irq_mask_cur;
+        uint8_t                 irq_trig_raise;
+        uint8_t                 irq_trig_fall;
+        uint8_t                 irq_features;
 #endif
 };
 
@@ -341,21 +343,27 @@ static int max732x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
         struct max732x_chip *chip;
 
         chip = container_of(gc, struct max732x_chip, gpio_chip);
-        return chip->irq_base + off;
+
+        if (chip->irq_domain) {
+                return irq_create_mapping(chip->irq_domain,
+                                chip->irq_base + off);
+        } else {
+                return -ENXIO;
+        }
 }
 
 static void max732x_irq_mask(struct irq_data *d)
 {
         struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
 
-        chip->irq_mask_cur &= ~(1 << (d->irq - chip->irq_base));
+        chip->irq_mask_cur &= ~(1 << d->hwirq);
 }
 
 static void max732x_irq_unmask(struct irq_data *d)
 {
         struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
 
-        chip->irq_mask_cur |= 1 << (d->irq - chip->irq_base);
+        chip->irq_mask_cur |= 1 << d->hwirq;
 }
 
 static void max732x_irq_bus_lock(struct irq_data *d)
@@ -377,7 +385,7 @@ static void max732x_irq_bus_sync_unlock(struct irq_data *d)
 static int max732x_irq_set_type(struct irq_data *d, unsigned int type)
 {
         struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
-        uint16_t off = d->irq - chip->irq_base;
+        uint16_t off = d->hwirq;
         uint16_t mask = 1 << off;
 
         if (!(mask & chip->dir_input)) {
@@ -458,7 +466,7 @@ static irqreturn_t max732x_irq_handler(int irq, void *devid)
 
         do {
                 level = __ffs(pending);
-                handle_nested_irq(level + chip->irq_base);
+                handle_nested_irq(irq_find_mapping(chip->irq_domain, level));
 
                 pending &= ~(1 << level);
         } while (pending);
@@ -466,6 +474,44 @@ static irqreturn_t max732x_irq_handler(int irq, void *devid)
         return IRQ_HANDLED;
 }
 
+static int max732x_irq_map(struct irq_domain *h, unsigned int virq,
+                irq_hw_number_t hw)
+{
+        struct max732x_chip *chip = h->host_data;
+
+        if (!(chip->dir_input & (1 << hw))) {
+                dev_err(&chip->client->dev,
+                                "Attempt to map output line as IRQ line: %lu\n",
+                                hw);
+                return -EPERM;
+        }
+
+        irq_set_chip_data(virq, chip);
+        irq_set_chip_and_handler(virq, &max732x_irq_chip,
+                        handle_edge_irq);
+        irq_set_nested_thread(virq, 1);
+#ifdef CONFIG_ARM
+        /* ARM needs us to explicitly flag the IRQ as valid
+         * and will set them noprobe when we do so. */
+        set_irq_flags(virq, IRQF_VALID);
+#else
+        irq_set_noprobe(virq);
+#endif
+
+        return 0;
+}
+
+static struct irq_domain_ops max732x_irq_domain_ops = {
+        .map    = max732x_irq_map,
+        .xlate  = irq_domain_xlate_twocell,
+};
+
+static void max732x_irq_teardown(struct max732x_chip *chip)
+{
+        if (chip->client->irq && chip->irq_domain)
+                irq_domain_remove(chip->irq_domain);
+}
+
 static int max732x_irq_setup(struct max732x_chip *chip,
                              const struct i2c_device_id *id)
 {
@@ -476,28 +522,17 @@ static int max732x_irq_setup(struct max732x_chip *chip,
 
         if (((pdata && pdata->irq_base) || client->irq)
                         && has_irq != INT_NONE) {
-                int lvl;
-
                 if (pdata)
                         chip->irq_base = pdata->irq_base;
                 chip->irq_features = has_irq;
                 mutex_init(&chip->irq_lock);
 
-                for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) {
-                        int irq = lvl + chip->irq_base;
-
-                        if (!(chip->dir_input & (1 << lvl)))
-                                continue;
-
-                        irq_set_chip_data(irq, chip);
-                        irq_set_chip_and_handler(irq, &max732x_irq_chip,
-                                                 handle_edge_irq);
-                        irq_set_nested_thread(irq, 1);
-#ifdef CONFIG_ARM
-                        set_irq_flags(irq, IRQF_VALID);
-#else
-                        irq_set_noprobe(irq);
-#endif
+                chip->irq_domain = irq_domain_add_simple(client->dev.of_node,
+                                chip->gpio_chip.ngpio, chip->irq_base,
+                                &max732x_irq_domain_ops, chip);
+                if (!chip->irq_domain) {
+                        dev_err(&client->dev, "Failed to create IRQ domain\n");
+                        return -ENOMEM;
                 }
 
                 ret = request_threaded_irq(client->irq,
@@ -517,15 +552,10 @@ static int max732x_irq_setup(struct max732x_chip *chip,
         return 0;
 
 out_failed:
-        chip->irq_base = 0;
+        max732x_irq_teardown(chip);
         return ret;
 }
 
-static void max732x_irq_teardown(struct max732x_chip *chip)
-{
-        if (chip->irq_base)
-                free_irq(chip->client->irq, chip);
-}
 #else /* CONFIG_GPIO_MAX732X_IRQ */
 static int max732x_irq_setup(struct max732x_chip *chip,
                              const struct i2c_device_id *id)