[PATCH v2 10/16] ACPI: bus: Introduce acpi_dev_for_each_child_reverse()

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Make it possible to walk the children of an ACPI device in the revese
order by defining acpi_dev_for_each_child_reverse() in analogy with
acpi_dev_for_each_child().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

v1 -> v2:
   * Do not break the acpi_dev_for_each_child() call line (Andy).
   * Add R-by from Andy.

---
 drivers/acpi/bus.c      |   12 ++++++++++++
 include/acpi/acpi_bus.h |    3 +++
 2 files changed, 15 insertions(+)

Index: linux-pm/drivers/acpi/bus.c
===================================================================
--- linux-pm.orig/drivers/acpi/bus.c
+++ linux-pm/drivers/acpi/bus.c
@@ -1115,6 +1115,18 @@ int acpi_dev_for_each_child(struct acpi_
 	return device_for_each_child(&adev->dev, &adwc, acpi_dev_for_one_check);
 }
 
+int acpi_dev_for_each_child_reverse(struct acpi_device *adev,
+				    int (*fn)(struct acpi_device *, void *),
+				    void *data)
+{
+	struct acpi_dev_walk_context adwc = {
+		.fn = fn,
+		.data = data,
+	};
+
+	return device_for_each_child_reverse(&adev->dev, &adwc, acpi_dev_for_one_check);
+}
+
 /* --------------------------------------------------------------------------
                              Initialization/Cleanup
    -------------------------------------------------------------------------- */
Index: linux-pm/include/acpi/acpi_bus.h
===================================================================
--- linux-pm.orig/include/acpi/acpi_bus.h
+++ linux-pm/include/acpi/acpi_bus.h
@@ -483,6 +483,9 @@ extern struct bus_type acpi_bus_type;
 int acpi_bus_for_each_dev(int (*fn)(struct device *, void *), void *data);
 int acpi_dev_for_each_child(struct acpi_device *adev,
 			    int (*fn)(struct acpi_device *, void *), void *data);
+int acpi_dev_for_each_child_reverse(struct acpi_device *adev,
+				    int (*fn)(struct acpi_device *, void *),
+				    void *data);
 
 /*
  * Events