Merge branch 'acpi-bus'

Merge changes related to primary "physical" device lookup for a given
ACPI device object that include the introduction of a new lookup helper
function and core ACPI device enumeration code updates putting that new
function to use (Rafael Wysocki)

* acpi-bus:
  ACPI: scan: Use acpi_bus_get_primary_device()
  ACPI: platform: Use acpi_bus_get_primary_device()
  ACPI: bus: Introduce acpi_bus_get_primary_device()

4 files changed, 60 insertions, 36 deletions

diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c
index e3c77a65f61c..80ea7121744d 100644
--- a/drivers/acpi/acpi_platform.c
+++ b/drivers/acpi/acpi_platform.c
@@ -108,18 +108,15 @@ static unsigned int acpi_platform_adjust_resources(struct acpi_device *adev,
 	return count;
 }
 
-static void acpi_platform_fill_resource(struct acpi_device *adev,
-	const struct resource *src, struct resource *dest)
+static void acpi_platform_fill_resource(struct device *parent,
+					const struct resource *src,
+					struct resource *dest)
 {
-	struct device *parent;
-
 	*dest = *src;
-
 	/*
 	 * If the device has parent we need to take its resources into
 	 * account as well because this device might consume part of those.
 	 */
-	parent = acpi_get_first_physical_node(acpi_dev_parent(adev));
 	if (parent && dev_is_pci(parent))
 		dest->parent = pci_find_resource(to_pci_dev(parent), dest);
 }
@@ -147,7 +144,8 @@ static unsigned int acpi_platform_resource_count(struct acpi_resource *ares, voi
 struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
 						    const struct property_entry *properties)
 {
-	struct acpi_device *parent = acpi_dev_parent(adev);
+	struct acpi_device *p = acpi_dev_parent(adev);
+	struct device *parent __free(put_device) = acpi_bus_get_primary_device(p);
 	struct platform_device *pdev = NULL;
 	struct platform_device_info pdevinfo;
 	const struct acpi_device_id *match;
@@ -193,7 +191,7 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
 								       rentry->res,
 								       resources,
 								       count);
-				acpi_platform_fill_resource(adev, rentry->res,
+				acpi_platform_fill_resource(parent, rentry->res,
 							    &resources[count++]);
 			}
 			acpi_dev_free_resource_list(&resource_list);
@@ -206,7 +204,7 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
 	 * attached to it, that physical device should be the parent of the
 	 * platform device we are about to create.
 	 */
-	pdevinfo.parent = parent ? acpi_get_first_physical_node(parent) : NULL;
+	pdevinfo.parent = parent;
 	pdevinfo.name = dev_name(&adev->dev);
 	pdevinfo.id = PLATFORM_DEVID_NONE;
 	pdevinfo.res = resources;
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index c1876f145ae4..ce50ce7a50da 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -774,30 +774,52 @@ static int __init acpi_setup_sb_notify_handler(void)
                              Device Matching
    -------------------------------------------------------------------------- */
 
+
+static struct device *primary_physical_device(struct acpi_device *adev)
+{
+	struct acpi_device_physical_node *pn;
+
+	pn = list_first_entry_or_null(&adev->physical_node_list,
+				      struct acpi_device_physical_node, node);
+	if (pn)
+		return pn->dev;
+
+	return NULL;
+}
+
+/**
+ * acpi_bus_get_primary_device - Get first physical device for a given ACPI one
+ * @adev: ACPI device to get the first physical device for.
+ *
+ * Find the first physical device for which @adev is the ACPI companion and
+ * reference count it if present.
+ *
+ * Return: Pointer to the first physical counterpart of @adev or NULL if there
+ * are none.  Callers are responsible for invoking put_device() on the returned
+ * device.
+ */
+struct device *acpi_bus_get_primary_device(struct acpi_device *adev)
+{
+	if (!adev)
+		return NULL;
+
+	guard(mutex)(&adev->physical_node_lock);
+
+	return get_device(primary_physical_device(adev));
+}
+EXPORT_SYMBOL_GPL(acpi_bus_get_primary_device);
+
 /**
- * acpi_get_first_physical_node - Get first physical node of an ACPI device
+ * acpi_get_first_physical_node - Find first physical node of an ACPI device
  * @adev:	ACPI device in question
  *
  * Return: First physical node of ACPI device @adev
  */
 struct device *acpi_get_first_physical_node(struct acpi_device *adev)
 {
-	struct mutex *physical_node_lock = &adev->physical_node_lock;
-	struct device *phys_dev;
-
-	mutex_lock(physical_node_lock);
-	if (list_empty(&adev->physical_node_list)) {
-		phys_dev = NULL;
-	} else {
-		const struct acpi_device_physical_node *node;
+	guard(mutex)(&adev->physical_node_lock);
 
-		node = list_first_entry(&adev->physical_node_list,
-					struct acpi_device_physical_node, node);
-
-		phys_dev = node->dev;
-	}
-	mutex_unlock(physical_node_lock);
-	return phys_dev;
+	return primary_physical_device(adev);
 }
 EXPORT_SYMBOL_GPL(acpi_get_first_physical_node);
 
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index b8a2f21dffd5..5f9b918fb6c5 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2208,29 +2208,27 @@ static void acpi_create_video_bus_device(struct acpi_device *adev,
 	struct auxiliary_device *aux_dev;
 	static unsigned int aux_dev_id;
 
+	struct device *phys_parent __free(put_device) = acpi_bus_get_primary_device(parent);
+	if (!phys_parent)
+		return;
+
 	aux_dev = kzalloc_obj(*aux_dev);
 	if (!aux_dev)
 		return;
 
 	aux_dev->id = aux_dev_id++;
 	aux_dev->name = "video_bus";
-	aux_dev->dev.parent = acpi_get_first_physical_node(parent);
-	if (!aux_dev->dev.parent)
-		goto err;
-
+	aux_dev->dev.parent = phys_parent;
 	aux_dev->dev.release = acpi_video_bus_device_release;
 
-	if (auxiliary_device_init(aux_dev))
-		goto err;
+	if (auxiliary_device_init(aux_dev)) {
+		kfree(aux_dev);
+		return;
+	}
 
 	ACPI_COMPANION_SET(&aux_dev->dev, adev);
 	if (__auxiliary_device_add(aux_dev, "acpi"))
 		auxiliary_device_uninit(aux_dev);
-
-	return;
-
-err:
-	kfree(aux_dev);
 }
 
 struct acpi_scan_system_dev {
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 32cac3a6f362..eaf13f6ac2d3 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -650,6 +650,7 @@ int acpi_scan_add_handler(struct acpi_scan_handler *handler);
 int acpi_bus_scan(acpi_handle handle);
 void acpi_bus_trim(struct acpi_device *start);
 acpi_status acpi_bus_get_ejd(acpi_handle handle, acpi_handle * ejd);
+struct device *acpi_bus_get_primary_device(struct acpi_device *adev);
 int acpi_match_device_ids(struct acpi_device *device,
 			  const struct acpi_device_id *ids);
 void acpi_set_modalias(struct acpi_device *adev, const char *default_id,
@@ -952,6 +953,11 @@ int acpi_scan_add_dep(acpi_handle handle, struct acpi_handle_list *dep_devices);
 u32 arch_acpi_add_auto_dep(acpi_handle handle);
 #else	/* CONFIG_ACPI */
 
+static inline struct device *acpi_bus_get_primary_device(struct acpi_device *adev)
+{
+	return NULL;
+}
+
 static inline bool acpi_of_match_device(const struct acpi_device *adev,
 					const struct of_device_id *of_match_table,
 					const struct of_device_id **of_id)