i2c: i801: Improve i801_acpi_probe/remove functions

By using ACPI_HANDLE() the handler argument can be retrieved directly.
Both address space handler functions check the handler argument and
return an error if it's NULL. This allows to further simplify the code.

Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

drivers/i2c/busses/i2c-i801.c

@@ -1635,31 +1635,22 @@ i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits,
 
 static int i801_acpi_probe(struct i801_priv *priv)
 {
-	struct acpi_device *adev;
+	acpi_handle ah = ACPI_HANDLE(&priv->pci_dev->dev);
 	acpi_status status;
 
-	adev = ACPI_COMPANION(&priv->pci_dev->dev);
-	if (adev) {
-		status = acpi_install_address_space_handler(adev->handle,
-				ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler,
-				NULL, priv);
-		if (ACPI_SUCCESS(status))
-			return 0;
-	}
+	status = acpi_install_address_space_handler(ah, ACPI_ADR_SPACE_SYSTEM_IO,
+						    i801_acpi_io_handler, NULL, priv);
+	if (ACPI_SUCCESS(status))
+		return 0;
 
 	return acpi_check_resource_conflict(&priv->pci_dev->resource[SMBBAR]);
 }
 
 static void i801_acpi_remove(struct i801_priv *priv)
 {
-	struct acpi_device *adev;
+	acpi_handle ah = ACPI_HANDLE(&priv->pci_dev->dev);
 
-	adev = ACPI_COMPANION(&priv->pci_dev->dev);
-	if (!adev)
-		return;
-
-	acpi_remove_address_space_handler(adev->handle,
-		ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler);
+	acpi_remove_address_space_handler(ah, ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler);
 }
 #else
 static inline int i801_acpi_probe(struct i801_priv *priv) { return 0; }