ACPI: scan: Rearrange dep_unmet initialization

The dep_unmet field in struct acpi_device is used to store the
number of unresolved _DEP dependencies (that is, operation region
dependencies for which there are no drivers present) for the ACPI
device object represented by it.

That field is initialized to 1 for all ACPI device objects in
acpi_add_single_object(), via acpi_init_device_object(), so as to
avoid evaluating _STA prematurely for battery device objects in
acpi_scan_init_status(), and it is "fixed up" in acpi_bus_check_add()
after the acpi_add_single_object() called by it has returned.

This is not particularly straightforward and causes dep_unmet to
remain 1 for device objects without dependencies created by invoking
acpi_add_single_object() directly, outside acpi_bus_check_add().

For this reason, rearrange acpi_add_single_object() to initialize
dep_unmet completely before calling acpi_scan_init_status(), which
requires passing one extra bool argument to it, and update all of
its callers accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 453eff8..a2df7bc 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1671,8 +1671,20 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
        device_initialize(&device->dev);
        dev_set_uevent_suppress(&device->dev, true);
        acpi_init_coherency(device);
-       /* Assume there are unmet deps to start with. */
-       device->dep_unmet = 1;
+}
+
+static void acpi_scan_dep_init(struct acpi_device *adev)
+{
+       struct acpi_dep_data *dep;
+
+       mutex_lock(&acpi_dep_list_lock);
+
+       list_for_each_entry(dep, &acpi_dep_list, node) {
+               if (dep->consumer == adev->handle)
+                       adev->dep_unmet++;
+       }
+
+       mutex_unlock(&acpi_dep_list_lock);
 }
 
 void acpi_device_add_finalize(struct acpi_device *device)
@@ -1688,7 +1700,7 @@ static void acpi_scan_init_status(struct acpi_device *adev)
 }
 
 static int acpi_add_single_object(struct acpi_device **child,
-                                 acpi_handle handle, int type)
+                                 acpi_handle handle, int type, bool dep_init)
 {
        struct acpi_device *device;
        int result;
@@ -1703,8 +1715,12 @@ static int acpi_add_single_object(struct acpi_device **child,
         * acpi_bus_get_status() and use its quirk handling.  Note that
         * this must be done before the get power-/wakeup_dev-flags calls.
         */
-       if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR)
+       if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) {
+               if (dep_init)
+                       acpi_scan_dep_init(device);
+
                acpi_scan_init_status(device);
+       }
 
        acpi_bus_get_power_flags(device);
        acpi_bus_get_wakeup_device_flags(device);
@@ -1886,22 +1902,6 @@ static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep)
        return count;
 }
 
-static void acpi_scan_dep_init(struct acpi_device *adev)
-{
-       struct acpi_dep_data *dep;
-
-       adev->dep_unmet = 0;
-
-       mutex_lock(&acpi_dep_list_lock);
-
-       list_for_each_entry(dep, &acpi_dep_list, node) {
-               if (dep->consumer == adev->handle)
-                       adev->dep_unmet++;
-       }
-
-       mutex_unlock(&acpi_dep_list_lock);
-}
-
 static bool acpi_bus_scan_second_pass;
 
 static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
@@ -1949,19 +1949,15 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
                return AE_OK;
        }
 
-       acpi_add_single_object(&device, handle, type);
-       if (!device)
-               return AE_CTRL_DEPTH;
-
-       acpi_scan_init_hotplug(device);
        /*
         * If check_dep is true at this point, the device has no dependencies,
         * or the creation of the device object would have been postponed above.
         */
-       if (check_dep)
-               device->dep_unmet = 0;
-       else
-               acpi_scan_dep_init(device);
+       acpi_add_single_object(&device, handle, type, !check_dep);
+       if (!device)
+               return AE_CTRL_DEPTH;
+
+       acpi_scan_init_hotplug(device);
 
 out:
        if (!*adev_p)
@@ -2223,7 +2219,7 @@ int acpi_bus_register_early_device(int type)
        struct acpi_device *device = NULL;
        int result;
 
-       result = acpi_add_single_object(&device, NULL, type);
+       result = acpi_add_single_object(&device, NULL, type, false);
        if (result)
                return result;
 
@@ -2243,7 +2239,7 @@ static int acpi_bus_scan_fixed(void)
                struct acpi_device *device = NULL;
 
                result = acpi_add_single_object(&device, NULL,
-                                               ACPI_BUS_TYPE_POWER_BUTTON);
+                                               ACPI_BUS_TYPE_POWER_BUTTON, false);
                if (result)
                        return result;
 
@@ -2259,7 +2255,7 @@ static int acpi_bus_scan_fixed(void)
                struct acpi_device *device = NULL;
 
                result = acpi_add_single_object(&device, NULL,
-                                               ACPI_BUS_TYPE_SLEEP_BUTTON);
+                                               ACPI_BUS_TYPE_SLEEP_BUTTON, false);
                if (result)
                        return result;