pinctrl: coh901: convert driver to use gpiolib irqchip

This converts the COH901 pin control driver to register its
chained irq handler and irqchip using the helpers in the
gpiolib core.

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

2 files changed, 54 insertions, 151 deletions

diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index a05087bd1955..0c6eb33daa87 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -324,6 +324,7 @@ config PINCTRL_U300
 config PINCTRL_COH901
         bool "ST-Ericsson U300 COH 901 335/571 GPIO"
         depends on GPIOLIB && ARCH_U300 && PINCTRL_U300
+        select GPIOLIB_IRQCHIP
         help
           Say yes here to support GPIO interface on ST-Ericsson U300.
           The names of the two IP block variants supported are
diff --git a/drivers/pinctrl/pinctrl-coh901.c b/drivers/pinctrl/pinctrl-coh901.c
index 749db595640c..d182fdd2e715 100644
--- a/drivers/pinctrl/pinctrl-coh901.c
+++ b/drivers/pinctrl/pinctrl-coh901.c
@@ -8,17 +8,14 @@
  * Author: Jonas Aaberg <jonas.aberg@stericsson.com>
  */
 #include <linux/module.h>
-#include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/io.h>
-#include <linux/irqdomain.h>
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
-#include <linux/list.h>
 #include <linux/slab.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/pinctrl/pinconf-generic.h>
@@ -61,9 +58,17 @@
 #define U300_GPIO_PINS_PER_PORT 8
 #define U300_GPIO_MAX (U300_GPIO_PINS_PER_PORT * U300_GPIO_NUM_PORTS)
 
+struct u300_gpio_port {
+        struct u300_gpio *gpio;
+        char name[8];
+        int irq;
+        int number;
+        u8 toggle_edge_mode;
+};
+
 struct u300_gpio {
         struct gpio_chip chip;
-        struct list_head port_list;
+        struct u300_gpio_port ports[U300_GPIO_NUM_PORTS];
         struct clk *clk;
         void __iomem *base;
         struct device *dev;
@@ -78,16 +83,6 @@ struct u300_gpio {
         u32 iev;
 };
 
-struct u300_gpio_port {
-        struct list_head node;
-        struct u300_gpio *gpio;
-        char name[8];
-        struct irq_domain *domain;
-        int irq;
-        int number;
-        u8 toggle_edge_mode;
-};
-
 /*
  * Macro to expand to read a specific register found in the "gpio"
  * struct. It requires the struct u300_gpio *gpio variable to exist in
@@ -308,39 +303,6 @@ static int u300_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
         return 0;
 }
 
-static int u300_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
-{
-        struct u300_gpio *gpio = to_u300_gpio(chip);
-        int portno = offset >> 3;
-        struct u300_gpio_port *port = NULL;
-        struct list_head *p;
-        int retirq;
-        bool found = false;
-
-        list_for_each(p, &gpio->port_list) {
-                port = list_entry(p, struct u300_gpio_port, node);
-                if (port->number == portno) {
-                        found = true;
-                        break;
-                }
-        }
-        if (!found) {
-                dev_err(gpio->dev, "could not locate port for GPIO %d IRQ\n",
-                        offset);
-                return -EINVAL;
-        }
-
-        /*
-         * The local hwirqs on the port are the lower three bits, there
-         * are exactly 8 IRQs per port since they are 8-bit
-         */
-        retirq = irq_find_mapping(port->domain, (offset & 0x7));
-
-        dev_dbg(gpio->dev, "request IRQ for GPIO %d, return %d from port %d\n",
-                offset, retirq, port->number);
-        return retirq;
-}
-
 /* Returning -EINVAL means "supported but not available" */
 int u300_gpio_config_get(struct gpio_chip *chip,
                          unsigned offset,
@@ -461,7 +423,6 @@ static struct gpio_chip u300_gpio_chip = {
         .set                    = u300_gpio_set,
         .direction_input        = u300_gpio_direction_input,
         .direction_output       = u300_gpio_direction_output,
-        .to_irq                 = u300_gpio_to_irq,
 };
 
 static void u300_toggle_trigger(struct u300_gpio *gpio, unsigned offset)
@@ -485,9 +446,10 @@ static void u300_toggle_trigger(struct u300_gpio *gpio, unsigned offset)
 
 static int u300_gpio_irq_type(struct irq_data *d, unsigned trigger)
 {
-        struct u300_gpio_port *port = irq_data_get_irq_chip_data(d);
-        struct u300_gpio *gpio = port->gpio;
-        int offset = (port->number << 3) + d->hwirq;
+        struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+        struct u300_gpio *gpio = to_u300_gpio(chip);
+        struct u300_gpio_port *port = &gpio->ports[d->hwirq >> 3];
+        int offset = d->hwirq;
         u32 val;
 
         if ((trigger & IRQF_TRIGGER_RISING) &&
@@ -521,9 +483,10 @@ static int u300_gpio_irq_type(struct irq_data *d, unsigned trigger)
 
 static void u300_gpio_irq_enable(struct irq_data *d)
 {
-        struct u300_gpio_port *port = irq_data_get_irq_chip_data(d);
-        struct u300_gpio *gpio = port->gpio;
-        int offset = (port->number << 3) + d->hwirq;
+        struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+        struct u300_gpio *gpio = to_u300_gpio(chip);
+        struct u300_gpio_port *port = &gpio->ports[d->hwirq >> 3];
+        int offset = d->hwirq;
         u32 val;
         unsigned long flags;
 
@@ -537,9 +500,9 @@ static void u300_gpio_irq_enable(struct irq_data *d)
 
 static void u300_gpio_irq_disable(struct irq_data *d)
 {
-        struct u300_gpio_port *port = irq_data_get_irq_chip_data(d);
-        struct u300_gpio *gpio = port->gpio;
-        int offset = (port->number << 3) + d->hwirq;
+        struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+        struct u300_gpio *gpio = to_u300_gpio(chip);
+        int offset = d->hwirq;
         u32 val;
         unsigned long flags;
 
@@ -549,45 +512,24 @@ static void u300_gpio_irq_disable(struct irq_data *d)
         local_irq_restore(flags);
 }
 
-static int u300_gpio_irq_reqres(struct irq_data *d)
-{
-        struct u300_gpio_port *port = irq_data_get_irq_chip_data(d);
-        struct u300_gpio *gpio = port->gpio;
-
-        if (gpio_lock_as_irq(&gpio->chip, d->hwirq)) {
-                dev_err(gpio->dev,
-                        "unable to lock HW IRQ %lu for IRQ\n",
-                        d->hwirq);
-                return -EINVAL;
-        }
-        return 0;
-}
-
-static void u300_gpio_irq_relres(struct irq_data *d)
-{
-        struct u300_gpio_port *port = irq_data_get_irq_chip_data(d);
-        struct u300_gpio *gpio = port->gpio;
-
-        gpio_unlock_as_irq(&gpio->chip, d->hwirq);
-}
-
 static struct irq_chip u300_gpio_irqchip = {
         .name                   = "u300-gpio-irqchip",
         .irq_enable             = u300_gpio_irq_enable,
         .irq_disable            = u300_gpio_irq_disable,
         .irq_set_type           = u300_gpio_irq_type,
-        .irq_request_resources  = u300_gpio_irq_reqres,
-        .irq_release_resources  = u300_gpio_irq_relres,
 };
 
 static void u300_gpio_irq_handler(unsigned irq, struct irq_desc *desc)
 {
-        struct u300_gpio_port *port = irq_get_handler_data(irq);
-        struct u300_gpio *gpio = port->gpio;
+        struct irq_chip *parent_chip = irq_get_chip(irq);
+        struct gpio_chip *chip = irq_get_handler_data(irq);
+        struct u300_gpio *gpio = to_u300_gpio(chip);
+        struct u300_gpio_port *port = &gpio->ports[irq - chip->base];
         int pinoffset = port->number << 3; /* get the right stride */
         unsigned long val;
 
-        desc->irq_data.chip->irq_ack(&desc->irq_data);
+        chained_irq_enter(parent_chip, desc);
+
         /* Read event register */
         val = readl(U300_PIN_REG(pinoffset, iev));
         /* Mask relevant bits */
@@ -600,8 +542,8 @@ static void u300_gpio_irq_handler(unsigned irq, struct irq_desc *desc)
                 int irqoffset;
 
                 for_each_set_bit(irqoffset, &val, U300_GPIO_PINS_PER_PORT) {
-                        int pin_irq = irq_find_mapping(port->domain, irqoffset);
                         int offset = pinoffset + irqoffset;
+                        int pin_irq = irq_find_mapping(chip->irqdomain, offset);
 
                         dev_dbg(gpio->dev, "GPIO IRQ %d on pin %d\n",
                                 pin_irq, offset);
@@ -615,7 +557,7 @@ static void u300_gpio_irq_handler(unsigned irq, struct irq_desc *desc)
                 }
         }
 
-        desc->irq_data.chip->irq_unmask(&desc->irq_data);
+        chained_irq_exit(parent_chip, desc);
 }
 
 static void __init u300_gpio_init_pin(struct u300_gpio *gpio,
@@ -666,20 +608,6 @@ static void __init u300_gpio_init_coh901571(struct u300_gpio *gpio)
         }
 }
 
-static inline void u300_gpio_free_ports(struct u300_gpio *gpio)
-{
-        struct u300_gpio_port *port;
-        struct list_head *p, *n;
-
-        list_for_each_safe(p, n, &gpio->port_list) {
-                port = list_entry(p, struct u300_gpio_port, node);
-                list_del(&port->node);
-                if (port->domain)
-                        irq_domain_remove(port->domain);
-                kfree(port);
-        }
-}
-
 /*
  * Here we map a GPIO in the local gpio_chip pin space to a pin in
  * the local pinctrl pin space. The pin controller used is
@@ -770,17 +698,28 @@ static int __init u300_gpio_probe(struct platform_device *pdev)
                gpio->base + U300_GPIO_CR);
         u300_gpio_init_coh901571(gpio);
 
+#ifdef CONFIG_OF_GPIO
+        gpio->chip.of_node = pdev->dev.of_node;
+#endif
+        err = gpiochip_add(&gpio->chip);
+        if (err) {
+                dev_err(gpio->dev, "unable to add gpiochip: %d\n", err);
+                goto err_no_chip;
+        }
+
+        err = gpiochip_irqchip_add(&gpio->chip,
+                                   &u300_gpio_irqchip,
+                                   0,
+                                   handle_simple_irq,
+                                   IRQ_TYPE_EDGE_FALLING);
+        if (err) {
+                dev_err(gpio->dev, "no GPIO irqchip\n");
+                goto err_no_irqchip;
+        }
+
         /* Add each port with its IRQ separately */
-        INIT_LIST_HEAD(&gpio->port_list);
         for (portno = 0 ; portno < U300_GPIO_NUM_PORTS; portno++) {
-                struct u300_gpio_port *port =
-                        kmalloc(sizeof(struct u300_gpio_port), GFP_KERNEL);
-
-                if (!port) {
-                        dev_err(gpio->dev, "out of memory\n");
-                        err = -ENOMEM;
-                        goto err_no_port;
-                }
+                struct u300_gpio_port *port = &gpio->ports[portno];
 
                 snprintf(port->name, 8, "gpio%d", portno);
                 port->number = portno;
@@ -788,50 +727,16 @@ static int __init u300_gpio_probe(struct platform_device *pdev)
 
                 port->irq = platform_get_irq(pdev, portno);
 
-                dev_dbg(gpio->dev, "register IRQ %d for port %s\n", port->irq,
-                        port->name);
-
-                port->domain = irq_domain_add_linear(pdev->dev.of_node,
-                                                     U300_GPIO_PINS_PER_PORT,
-                                                     &irq_domain_simple_ops,
-                                                     port);
-                if (!port->domain) {
-                        err = -ENOMEM;
-                        goto err_no_domain;
-                }
-
-                irq_set_chained_handler(port->irq, u300_gpio_irq_handler);
-                irq_set_handler_data(port->irq, port);
-
-                /* For each GPIO pin set the unique IRQ handler */
-                for (i = 0; i < U300_GPIO_PINS_PER_PORT; i++) {
-                        int irqno = irq_create_mapping(port->domain, i);
-
-                        dev_dbg(gpio->dev, "GPIO%d on port %s gets IRQ %d\n",
-                                gpio->chip.base + (port->number << 3) + i,
-                                port->name, irqno);
-                        irq_set_chip_and_handler(irqno, &u300_gpio_irqchip,
-                                                 handle_simple_irq);
-                        set_irq_flags(irqno, IRQF_VALID);
-                        irq_set_chip_data(irqno, port);
-                }
+                gpiochip_set_chained_irqchip(&gpio->chip,
+                                             &u300_gpio_irqchip,
+                                             port->irq,
+                                             u300_gpio_irq_handler);
 
                 /* Turns off irq force (test register) for this port */
                 writel(0x0, gpio->base + portno * gpio->stride + ifr);
-
-                list_add_tail(&port->node, &gpio->port_list);
         }
         dev_dbg(gpio->dev, "initialized %d GPIO ports\n", portno);
 
-#ifdef CONFIG_OF_GPIO
-        gpio->chip.of_node = pdev->dev.of_node;
-#endif
-        err = gpiochip_add(&gpio->chip);
-        if (err) {
-                dev_err(gpio->dev, "unable to add gpiochip: %d\n", err);
-                goto err_no_chip;
-        }
-
         /*
          * Add pinctrl pin ranges, the pin controller must be registered
          * at this point
@@ -850,12 +755,10 @@ static int __init u300_gpio_probe(struct platform_device *pdev)
         return 0;
 
 err_no_range:
+err_no_irqchip:
         if (gpiochip_remove(&gpio->chip))
                 dev_err(&pdev->dev, "failed to remove gpio chip\n");
 err_no_chip:
-err_no_domain:
-err_no_port:
-        u300_gpio_free_ports(gpio);
         clk_disable_unprepare(gpio->clk);
         dev_err(&pdev->dev, "module ERROR:%d\n", err);
         return err;
@@ -874,7 +777,6 @@ static int __exit u300_gpio_remove(struct platform_device *pdev)
                 dev_err(gpio->dev, "unable to remove gpiochip: %d\n", err);
                 return err;
         }
-        u300_gpio_free_ports(gpio);
         clk_disable_unprepare(gpio->clk);
         return 0;
 }