ACPI: Introduce has_acpi_companion()

Now that the ACPI companions of devices are represented by pointers
to struct fwnode_handle, it is not quite efficient to check whether
or not an ACPI companion of a device is present by evaluating the
ACPI_COMPANION() macro.

For this reason, introduce a special static inline routine for that,
has_acpi_companion(), and update the code to use it where applicable.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 402ddbdc2da1..ec488d03b518 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -58,6 +58,11 @@ static inline acpi_handle acpi_device_handle(struct acpi_device *adev)
 	acpi_fwnode_handle(adev) : NULL
 #define ACPI_HANDLE(dev)		acpi_device_handle(ACPI_COMPANION(dev))
 
+static inline bool has_acpi_companion(struct device *dev)
+{
+	return is_acpi_node(dev->fwnode);
+}
+
 static inline void acpi_preset_companion(struct device *dev,
 					 struct acpi_device *parent, u64 addr)
 {
@@ -472,6 +477,11 @@ static inline struct fwnode_handle *acpi_fwnode_handle(struct acpi_device *adev)
 	return NULL;
 }
 
+static inline bool has_acpi_companion(struct device *dev)
+{
+	return false;
+}
+
 static inline const char *acpi_dev_name(struct acpi_device *adev)
 {
 	return NULL;