gpio: max732x: convert to GPIOLIB_IRQCHIP

Take a sweep to bring the irq support for the MAX732x expanders
into the gpiolib core to cut down on duplicated code.

Only compile tested! I need some feedback from people using this
expander with interrupts to tell me if things go right or
wrong when I do this.

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

2 files changed, 43 insertions, 93 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index c1e2ca3d9a51..09bc70b3875b 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -543,7 +543,6 @@ 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
@@ -563,6 +562,7 @@ config GPIO_MAX732X
 config GPIO_MAX732X_IRQ
         bool "Interrupt controller support for MAX732x"
         depends on GPIO_MAX732X=y
+        select GPIOLIB_IRQCHIP
         help
           Say yes here to enable the max732x to be used as an interrupt
           controller. It requires the driver to be built in the kernel.
diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index a095b2393fe9..0fa4543c5e02 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -4,6 +4,7 @@
  *  Copyright (C) 2007 Marvell International Ltd.
  *  Copyright (C) 2008 Jack Ren <jack.ren@marvell.com>
  *  Copyright (C) 2008 Eric Miao <eric.miao@marvell.com>
+ *  Copyright (C) 2015 Linus Walleij <linus.walleij@linaro.org>
  *
  *  Derived from drivers/gpio/pca953x.c
  *
@@ -16,10 +17,8 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/string.h>
-#include <linux/gpio.h>
+#include <linux/gpio/driver.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>
@@ -150,9 +149,7 @@ struct max732x_chip {
         uint8_t         reg_out[2];
 
 #ifdef CONFIG_GPIO_MAX732X_IRQ
-        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;
@@ -356,35 +353,26 @@ static void max732x_irq_update_mask(struct max732x_chip *chip)
         mutex_unlock(&chip->lock);
 }
 
-static int max732x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
-{
-        struct max732x_chip *chip = to_max732x(gc);
-
-        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);
+        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+        struct max732x_chip *chip = to_max732x(gc);
 
         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);
+        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+        struct max732x_chip *chip = to_max732x(gc);
 
         chip->irq_mask_cur |= 1 << d->hwirq;
 }
 
 static void max732x_irq_bus_lock(struct irq_data *d)
 {
-        struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
+        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+        struct max732x_chip *chip = to_max732x(gc);
 
         mutex_lock(&chip->irq_lock);
         chip->irq_mask_cur = chip->irq_mask;
@@ -392,7 +380,8 @@ static void max732x_irq_bus_lock(struct irq_data *d)
 
 static void max732x_irq_bus_sync_unlock(struct irq_data *d)
 {
-        struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
+        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+        struct max732x_chip *chip = to_max732x(gc);
         uint16_t new_irqs;
         uint16_t level;
 
@@ -410,7 +399,8 @@ 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);
+        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+        struct max732x_chip *chip = to_max732x(gc);
         uint16_t off = d->hwirq;
         uint16_t mask = 1 << off;
 
@@ -492,7 +482,8 @@ static irqreturn_t max732x_irq_handler(int irq, void *devid)
 
         do {
                 level = __ffs(pending);
-                handle_nested_irq(irq_find_mapping(chip->irq_domain, level));
+                handle_nested_irq(irq_find_mapping(chip->gpio_chip.irqdomain,
+                                                   level));
 
                 pending &= ~(1 << level);
         } while (pending);
@@ -500,86 +491,50 @@ 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)
 {
         struct i2c_client *client = chip->client;
         struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
         int has_irq = max732x_features[id->driver_data] >> 32;
+        int irq_base = 0;
         int ret;
 
         if (((pdata && pdata->irq_base) || client->irq)
                         && has_irq != INT_NONE) {
                 if (pdata)
-                        chip->irq_base = pdata->irq_base;
+                        irq_base = pdata->irq_base;
                 chip->irq_features = has_irq;
                 mutex_init(&chip->irq_lock);
 
-                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,
-                                           NULL,
-                                           max732x_irq_handler,
-                                           IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
-                                           dev_name(&client->dev), chip);
+                ret = devm_request_threaded_irq(&client->dev,
+                                        client->irq,
+                                        NULL,
+                                        max732x_irq_handler,
+                                        IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+                                        dev_name(&client->dev), chip);
                 if (ret) {
                         dev_err(&client->dev, "failed to request irq %d\n",
                                 client->irq);
-                        goto out_failed;
+                        return ret;
                 }
-
-                chip->gpio_chip.to_irq = max732x_gpio_to_irq;
+                ret =  gpiochip_irqchip_add(&chip->gpio_chip,
+                                            &max732x_irq_chip,
+                                            irq_base,
+                                            handle_edge_irq,
+                                            IRQ_TYPE_NONE);
+                if (ret) {
+                        dev_err(&client->dev,
+                                "could not connect irqchip to gpiochip\n");
+                        return ret;
+                }
+                gpiochip_set_chained_irqchip(&chip->gpio_chip,
+                                             &max732x_irq_chip,
+                                             client->irq,
+                                             NULL);
         }
 
         return 0;
-
-out_failed:
-        max732x_irq_teardown(chip);
-        return ret;
 }
 
 #else /* CONFIG_GPIO_MAX732X_IRQ */
@@ -595,10 +550,6 @@ static int max732x_irq_setup(struct max732x_chip *chip,
 
         return 0;
 }
-
-static void max732x_irq_teardown(struct max732x_chip *chip)
-{
-}
 #endif
 
 static int max732x_setup_gpio(struct max732x_chip *chip,
@@ -730,13 +681,15 @@ static int max732x_probe(struct i2c_client *client,
         if (nr_port > 8)
                 max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]);
 
-        ret = max732x_irq_setup(chip, id);
+        ret = gpiochip_add(&chip->gpio_chip);
         if (ret)
                 goto out_failed;
 
-        ret = gpiochip_add(&chip->gpio_chip);
-        if (ret)
+        ret = max732x_irq_setup(chip, id);
+        if (ret) {
+                gpiochip_remove(&chip->gpio_chip);
                 goto out_failed;
+        }
 
         if (pdata && pdata->setup) {
                 ret = pdata->setup(client, chip->gpio_chip.base,
@@ -751,7 +704,6 @@ static int max732x_probe(struct i2c_client *client,
 out_failed:
         if (chip->client_dummy)
                 i2c_unregister_device(chip->client_dummy);
-        max732x_irq_teardown(chip);
         return ret;
 }
 
@@ -774,8 +726,6 @@ static int max732x_remove(struct i2c_client *client)
 
         gpiochip_remove(&chip->gpio_chip);
 
-        max732x_irq_teardown(chip);
-
         /* unregister any dummy i2c_client */
         if (chip->client_dummy)
                 i2c_unregister_device(chip->client_dummy);