[PATCH v3 4/6] i2c: core: Move ACPI IRQ handling to probe time

[Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>]

Bring the ACPI path in sync with the device tree path and handle all the
IRQ fetching at probe time. This leaves the only IRQ handling at device
registration time being that which is passed directly through the board
info as either a resource or an actual IRQ number.

Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
---

Changes since v2:
 - Add kernel doc for i2c_acpi_get_irq

Thanks,
Charles

 drivers/i2c/i2c-core-acpi.c | 16 ++++++++++------
 drivers/i2c/i2c-core-base.c |  5 ++++-
 drivers/i2c/i2c-core.h      |  7 +++++++
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index c107f260e252f..62a938c17cbd2 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -148,8 +148,17 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
 	return 1; /* No need to add resource to the list */
 }
 
-static int i2c_acpi_get_irq(struct acpi_device *adev)
+/**
+ * i2c_acpi_get_irq - get device IRQ number from ACPI
+ * @client: Pointer to the I2C client device
+ *
+ * Find the IRQ number used by a specific client device.
+ *
+ * Return: The IRQ number or an error code.
+ */
+int i2c_acpi_get_irq(struct i2c_client *client)
 {
+	struct acpi_device *adev = ACPI_COMPANION(&client->adapter->dev);
 	struct list_head resource_list;
 	int irq = -ENOENT;
 	int ret;
@@ -201,11 +210,6 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
 	if (adapter_handle)
 		*adapter_handle = lookup.adapter_handle;
 
-	/* Then fill IRQ number if any */
-	ret = i2c_acpi_get_irq(adev);
-	if (ret > 0)
-		info->irq = ret;
-
 	acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
 			  sizeof(info->type));
 
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 84bf11b25a120..b6b009bfe842b 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -335,7 +335,10 @@ static int i2c_device_probe(struct device *dev)
 			if (irq == -EINVAL || irq == -ENODATA)
 				irq = of_irq_get(dev->of_node, 0);
 		} else if (ACPI_COMPANION(dev)) {
-			irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
+			irq = i2c_acpi_get_irq(client);
+
+			if (irq == -ENOENT)
+				irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
 		}
 		if (irq == -EPROBE_DEFER)
 			return irq;
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 8f3a08dc73a25..15c1411f35f07 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -72,6 +72,8 @@ const struct acpi_device_id *
 i2c_acpi_match_device(const struct acpi_device_id *matches,
 		      struct i2c_client *client);
 void i2c_acpi_register_devices(struct i2c_adapter *adap);
+
+int i2c_acpi_get_irq(struct i2c_client *client);
 #else /* CONFIG_ACPI */
 static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
 static inline const struct acpi_device_id *
@@ -80,6 +82,11 @@ i2c_acpi_match_device(const struct acpi_device_id *matches,
 {
 	return NULL;
 }
+
+static inline int i2c_acpi_get_irq(struct i2c_client *client)
+{
+	return 0;
+}
 #endif /* CONFIG_ACPI */
 extern struct notifier_block i2c_acpi_notifier;
 
-- 
2.11.0