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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-04-04 18:23:13 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-04-13 18:26:22 +0300
commitb7dd6298db81ea6dd902f1787eaf9a43228e2707 (patch)
tree7e7441978de497412d45c815b344957e17445f59 /drivers/acpi
parentcf6ba0750a22a54f5101986401271429995cc4a0 (diff)
downloadlinux-b7dd6298db81ea6dd902f1787eaf9a43228e2707.tar.xz
ACPI: PM: Introduce acpi_dev_power_up_children_with_adr()
Introduce a function powering up all of the children of a given ACPI device object that are power-manageable and hold valid _ADR ACPI objects so as to make it possible to prepare the corresponding "physical" devices for enumeration carried out by a bus type driver, like PCI. This function will be used in a subsequent change set. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Diffstat (limited to 'drivers/acpi')
-rw-r--r--drivers/acpi/device_pm.c30
1 files changed, 30 insertions, 0 deletions
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index cc6c97e7dcae..83598b11a7cc 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -425,6 +425,36 @@ bool acpi_bus_power_manageable(acpi_handle handle)
}
EXPORT_SYMBOL(acpi_bus_power_manageable);
+static int acpi_power_up_if_adr_present(struct device *dev, void *not_used)
+{
+ struct acpi_device *adev;
+
+ adev = to_acpi_device(dev);
+ if (!(adev->flags.power_manageable && adev->pnp.type.bus_address))
+ return 0;
+
+ acpi_handle_debug(adev->handle, "Power state: %s\n",
+ acpi_power_state_string(adev->power.state));
+
+ if (adev->power.state == ACPI_STATE_D3_COLD)
+ return acpi_device_set_power(adev, ACPI_STATE_D0);
+
+ return 0;
+}
+
+/**
+ * acpi_dev_power_up_children_with_adr - Power up childres with valid _ADR
+ * @adev: Parent ACPI device object.
+ *
+ * Change the power states of the direct children of @adev that are in D3cold
+ * and hold valid _ADR objects to D0 in order to allow bus (e.g. PCI)
+ * enumeration code to access them.
+ */
+void acpi_dev_power_up_children_with_adr(struct acpi_device *adev)
+{
+ acpi_dev_for_each_child(adev, acpi_power_up_if_adr_present, NULL);
+}
+
#ifdef CONFIG_PM
static DEFINE_MUTEX(acpi_pm_notifier_lock);
static DEFINE_MUTEX(acpi_pm_notifier_install_lock);