[PATCH v1 2/5] ACPI: scan: Rearrange checks in acpi_bus_check_add()

From: Rafael J. Wysocki
Date: Wed Apr 07 2021 - 10:34:17 EST


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

Rearrange the checks in acpi_bus_check_add() to avoid checking
the "type" twice and take "check_dep" into account only for
ACPI_TYPE_DEVICE objects.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/acpi/scan.c | 30 +++++++++++-------------------
1 file changed, 11 insertions(+), 19 deletions(-)

Index: linux-pm/drivers/acpi/scan.c
===================================================================
--- linux-pm.orig/drivers/acpi/scan.c
+++ linux-pm/drivers/acpi/scan.c
@@ -1831,7 +1831,7 @@ static void acpi_scan_init_hotplug(struc
}
}

-static u32 acpi_scan_check_dep(acpi_handle handle)
+static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep)
{
struct acpi_handle_list dep_devices;
acpi_status status;
@@ -1844,7 +1844,8 @@ static u32 acpi_scan_check_dep(acpi_hand
* 2. ACPI nodes describing USB ports.
* Still, checking for _HID catches more then just these cases ...
*/
- if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID"))
+ if (!check_dep || !acpi_has_method(handle, "_DEP") ||
+ !acpi_has_method(handle, "_HID"))
return 0;

status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices);
@@ -1925,6 +1926,12 @@ static acpi_status acpi_bus_check_add(ac
if (acpi_device_should_be_hidden(handle))
return AE_OK;

+ /* Bail out if there are dependencies. */
+ if (acpi_scan_check_dep(handle, check_dep) > 0) {
+ acpi_bus_scan_second_pass = true;
+ return AE_CTRL_DEPTH;
+ }
+
fallthrough;
case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */
type = ACPI_BUS_TYPE_DEVICE;
@@ -1942,27 +1949,12 @@ static acpi_status acpi_bus_check_add(ac
break;

case ACPI_TYPE_POWER:
- type = ACPI_BUS_TYPE_POWER;
- break;
-
- default:
- return AE_OK;
- }
-
- if (type == ACPI_BUS_TYPE_POWER) {
acpi_add_power_resource(handle);
+ fallthrough;
+ default:
return AE_OK;
}

- if (type == ACPI_BUS_TYPE_DEVICE && check_dep) {
- u32 count = acpi_scan_check_dep(handle);
- /* Bail out if the number of recorded dependencies is not 0. */
- if (count > 0) {
- acpi_bus_scan_second_pass = true;
- return AE_CTRL_DEPTH;
- }
- }
-
acpi_add_single_object(&device, handle, type, sta);
if (!device)
return AE_CTRL_DEPTH;