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>

1 files changed, 14 insertions, 8 deletions

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index d62eaaa75397..84540025aa08 100644
--- 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);
                 }