From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
It should be perfectly fine to use ACPI if the "fixed" power or sleep
buttons cannot be initialized. Moreover, running acpi_bus_scan()
successfully on ACPI_ROOT_OBJECT generally causes many devices to
be enumerated and probed, possibly including the entire PCI bus, so
unregistering acpi_root if the registration of the "fixed" buttons
fails is rather unhelpful.
For this reason, do not fail acpi_scan_init() when
acpi_bus_scan_fixed() fails and turn the latter into a void function.
While at it, drop the outdated and misleading comment from
acpi_bus_scan_fixed().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/acpi/scan.c | 58 ++++++++++++++++++----------------------------------
1 file changed, 21 insertions(+), 37 deletions(-)
Index: linux-pm/drivers/acpi/scan.c
===================================================================
--- linux-pm.orig/drivers/acpi/scan.c
+++ linux-pm/drivers/acpi/scan.c
@@ -2457,42 +2457,33 @@ int acpi_bus_register_early_device(int t
}
EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
-static int acpi_bus_scan_fixed(void)
+static void acpi_bus_scan_fixed(void)
{
- int result = 0;
-
- /*
- * Enumerate all fixed-feature devices.
- */
if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
- struct acpi_device *device = NULL;
+ struct acpi_device *adev = NULL;
- result = acpi_add_single_object(&device, NULL,
- ACPI_BUS_TYPE_POWER_BUTTON, false);
- if (result)
- return result;
-
- device->flags.match_driver = true;
- result = device_attach(&device->dev);
- if (result < 0)
- return result;
-
- device_init_wakeup(&device->dev, true);
+ acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_POWER_BUTTON,
+ false);
+ if (adev) {
+ adev->flags.match_driver = true;
+ if (device_attach(&adev->dev) >= 0)
+ device_init_wakeup(&adev->dev, true);
+ else
+ dev_dbg(&adev->dev, "No driver\n");
+ }
}
if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
- struct acpi_device *device = NULL;
+ struct acpi_device *adev = NULL;
- result = acpi_add_single_object(&device, NULL,
- ACPI_BUS_TYPE_SLEEP_BUTTON, false);
- if (result)
- return result;
-
- device->flags.match_driver = true;
- result = device_attach(&device->dev);
+ acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_SLEEP_BUTTON,
+ false);
+ if (adev) {
+ adev->flags.match_driver = true;
+ if (device_attach(&adev->dev) < 0)
+ dev_dbg(&adev->dev, "No driver\n");
+ }
}
-
- return result < 0 ? result : 0;
}
static void __init acpi_get_spcr_uart_addr(void)
@@ -2572,15 +2563,8 @@ void __init acpi_scan_init(void)
goto out;
/* Fixed feature devices do not exist on HW-reduced platform */
- if (!acpi_gbl_reduced_hardware) {
- if (acpi_bus_scan_fixed()) {
- acpi_detach_data(acpi_root->handle,
- acpi_scan_drop_device);
- acpi_device_del(acpi_root);
- acpi_bus_put_acpi_device(acpi_root);
- goto out;
- }
- }
+ if (!acpi_gbl_reduced_hardware)
+ acpi_bus_scan_fixed();
acpi_turn_off_unused_power_resources();
