gpio: acpi: normalize use of gpiochip_get_desc()

GPIO descriptors are changing from unique and permanent tokens to
allocated resources. Therefore gpiochip_get_desc() cannot be used as a
way to obtain a global GPIO descriptor anymore.

This patch updates the gpiolib ACPI support code to keep and use the
descriptor returned by a centralized call to gpiochip_get_desc().

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index d62eaaa..8454002 100644 (file)
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -25,10 +25,12 @@ struct acpi_gpio_event {
        acpi_handle handle;
        unsigned int pin;
        unsigned int irq;
+       struct gpio_desc *desc;
 };
 
 struct acpi_gpio_connection {
        struct list_head node;
+       unsigned int pin;
        struct gpio_desc *desc;
 };
 
@@ -197,6 +199,7 @@ static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
        event->handle = evt_handle;
        event->irq = irq;
        event->pin = pin;
+       event->desc = desc;
 
        ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
                                   "ACPI:Event", event);
@@ -280,7 +283,7 @@ void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
                struct gpio_desc *desc;
 
                free_irq(event->irq, event);
-               desc = gpiochip_get_desc(chip, event->pin);
+               desc = event->desc;
                if (WARN_ON(IS_ERR(desc)))
                        continue;
                gpio_unlock_as_irq(chip, event->pin);
@@ -406,24 +409,26 @@ acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
                struct gpio_desc *desc;
                bool found;
 
-               desc = gpiochip_get_desc(chip, pin);
-               if (IS_ERR(desc)) {
-                       status = AE_ERROR;
-                       goto out;
-               }
-
                mutex_lock(&achip->conn_lock);
 
                found = false;
                list_for_each_entry(conn, &achip->conns, node) {
-                       if (conn->desc == desc) {
+                       if (conn->pin == pin) {
                                found = true;
+                               desc = conn->desc;
                                break;
                        }
                }
                if (!found) {
                        int ret;
 
+                       desc = gpiochip_get_desc(chip, pin);
+                       if (IS_ERR(desc)) {
+                               status = AE_ERROR;
+                               mutex_unlock(&achip->conn_lock);
+                               goto out;
+                       }
+
                        ret = gpiochip_request_own_desc(desc, "ACPI:OpRegion");
                        if (ret) {
                                status = AE_ERROR;
@@ -462,6 +467,7 @@ acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
                                goto out;
                        }
 
+                       conn->pin = pin;
                        conn->desc = desc;
                        list_add_tail(&conn->node, &achip->conns);
                }