Merge branch 'acpi-bus'

Merge ACPI device object management changes for v5.20-rc1.

 - Use the facilities provided by the driver core and some additional
   helpers to handle the children of a given ACPI device object in
   multiple places instead of using the children and node list heads in
   struct acpi_device which is error prone (Rafael Wysocki).

 - Fix ACPI-related device reference counting issue in the hisi_lpc bus
   driver (Yang Yingliang).

 - Drop the children and node list heads that are not needed any more
   from struct acpi_device (Rafael Wysocki).

 - Drop driver member from struct acpi_device (Uwe Kleine-König).

 - Drop redundant check from acpi_device_remove() (Uwe Kleine-König).

* acpi-bus:
  ACPI: bus: Drop unused list heads from struct acpi_device
  hisi_lpc: Use acpi_dev_for_each_child()
  bus: hisi_lpc: fix missing platform_device_put() in hisi_lpc_acpi_probe()
  ACPI: bus: Drop driver member of struct acpi_device
  ACPI: bus: Drop redundant check in acpi_device_remove()
  mfd: core: Use acpi_dev_for_each_child()
  ACPI / MMC: PM: Unify fixing up device power
  soundwire: Use acpi_dev_for_each_child()
  platform/x86/thinkpad_acpi: Use acpi_dev_for_each_child()
  ACPI: scan: Walk ACPI device's children using driver core
  ACPI: bus: Introduce acpi_dev_for_each_child_reverse()
  ACPI: video: Use acpi_dev_for_each_child()
  ACPI: bus: Export acpi_dev_for_each_child() to modules
  ACPI: property: Use acpi_dev_for_each_child() for child lookup
  ACPI: container: Use acpi_dev_for_each_child()
  USB: ACPI: Replace usb_acpi_find_port() with acpi_find_child_by_adr()
  thunderbolt: ACPI: Replace tb_acpi_find_port() with acpi_find_child_by_adr()
  ACPI: glue: Introduce acpi_find_child_by_adr()
  ACPI: glue: Introduce acpi_dev_has_children()
  ACPI: glue: Use acpi_dev_for_each_child()

1 files changed, 27 insertions, 26 deletions

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index a8b383051528..502dcd1c33b7 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -6842,6 +6842,31 @@ static const struct backlight_ops ibm_backlight_data = {
 
 /* --------------------------------------------------------------------- */
 
+static int __init tpacpi_evaluate_bcl(struct acpi_device *adev, void *not_used)
+{
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj;
+	acpi_status status;
+	int rc;
+
+	status = acpi_evaluate_object(adev->handle, "_BCL", NULL, &buffer);
+	if (ACPI_FAILURE(status))
+		return 0;
+
+	obj = buffer.pointer;
+	if (!obj || obj->type != ACPI_TYPE_PACKAGE) {
+		acpi_handle_info(adev->handle,
+				 "Unknown _BCL data, please report this to %s\n",
+				 TPACPI_MAIL);
+		rc = 0;
+	} else {
+		rc = obj->package.count;
+	}
+	kfree(obj);
+
+	return rc;
+}
+
 /*
  * Call _BCL method of video device.  On some ThinkPads this will
  * switch the firmware to the ACPI brightness control mode.
@@ -6849,37 +6874,13 @@ static const struct backlight_ops ibm_backlight_data = {
 
 static int __init tpacpi_query_bcl_levels(acpi_handle handle)
 {
-	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object *obj;
-	struct acpi_device *device, *child;
-	int rc;
+	struct acpi_device *device;
 
 	device = acpi_fetch_acpi_dev(handle);
 	if (!device)
 		return 0;
 
-	rc = 0;
-	list_for_each_entry(child, &device->children, node) {
-		acpi_status status = acpi_evaluate_object(child->handle, "_BCL",
-							  NULL, &buffer);
-		if (ACPI_FAILURE(status)) {
-			buffer.length = ACPI_ALLOCATE_BUFFER;
-			continue;
-		}
-
-		obj = (union acpi_object *)buffer.pointer;
-		if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
-			pr_err("Unknown _BCL data, please report this to %s\n",
-				TPACPI_MAIL);
-			rc = 0;
-		} else {
-			rc = obj->package.count;
-		}
-		break;
-	}
-
-	kfree(buffer.pointer);
-	return rc;
+	return acpi_dev_for_each_child(device, tpacpi_evaluate_bcl, NULL);
 }