ACPI: introduce a function to find the first physical device

Factor out the code that finds the first physical device
of a given ACPI device.  It is used in several places.

Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c
index 296b7a14893aabba895c578e8671e36b34875a37..c3af1088bf6b88d322e72c8071d1e05a6d074460 100644 (file)
--- a/drivers/acpi/acpi_platform.c
+++ b/drivers/acpi/acpi_platform.c
@@ -43,7 +43,6 @@ static const struct acpi_device_id forbidden_id_list[] = {
 struct platform_device *acpi_create_platform_device(struct acpi_device *adev)
 {
        struct platform_device *pdev = NULL;
-       struct acpi_device *acpi_parent;
        struct platform_device_info pdevinfo;
        struct resource_entry *rentry;
        struct list_head resource_list;
@@ -82,22 +81,8 @@ 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 = NULL;
-       acpi_parent = adev->parent;
-       if (acpi_parent) {
-               struct acpi_device_physical_node *entry;
-               struct list_head *list;
-
-               mutex_lock(&acpi_parent->physical_node_lock);
-               list = &acpi_parent->physical_node_list;
-               if (!list_empty(list)) {
-                       entry = list_first_entry(list,
-                                       struct acpi_device_physical_node,
-                                       node);
-                       pdevinfo.parent = entry->dev;
-               }
-               mutex_unlock(&acpi_parent->physical_node_lock);
-       }
+       pdevinfo.parent = adev->parent ?
+               acpi_get_first_physical_node(adev->parent) : NULL;
        pdevinfo.name = dev_name(&adev->dev);
        pdevinfo.id = -1;
        pdevinfo.res = resources;

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 891c42d1cd652c732f4957fc8bb2c2f20a5fc470..0e8567846f1afbce5185361be758cb743c0b6836 100644 (file)
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -479,24 +479,38 @@ static void acpi_device_remove_notify_handler(struct acpi_device *device)
                              Device Matching
    -------------------------------------------------------------------------- */
 
-static struct acpi_device *acpi_primary_dev_companion(struct acpi_device *adev,
-                                                     const struct device *dev)
+/**
+ * acpi_get_first_physical_node - Get 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)) {
-               adev = NULL;
+               phys_dev = NULL;
        } else {
                const struct acpi_device_physical_node *node;
 
                node = list_first_entry(&adev->physical_node_list,
                                        struct acpi_device_physical_node, node);
-               if (node->dev != dev)
-                       adev = NULL;
+
+               phys_dev = node->dev;
        }
        mutex_unlock(physical_node_lock);
-       return adev;
+       return phys_dev;
+}
+
+static struct acpi_device *acpi_primary_dev_companion(struct acpi_device *adev,
+                                                     const struct device *dev)
+{
+       const struct device *phys_dev = acpi_get_first_physical_node(adev);
+
+       return phys_dev && phys_dev == dev ? adev : NULL;
 }
 
 /**

diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 1e6833a5cd44b6db55b5c9e376eceabfb44b30e0..8668891cb1fa91a27bf1bc683700aeec65da784e 100644 (file)
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -106,6 +106,7 @@ bool acpi_device_is_present(struct acpi_device *adev);
 bool acpi_device_is_battery(struct acpi_device *adev);
 bool acpi_device_is_first_physical_node(struct acpi_device *adev,
                                        const struct device *dev);
+struct device *acpi_get_first_physical_node(struct acpi_device *adev);
 
 /* --------------------------------------------------------------------------
                      Device Matching and Notification