Merge tag 'pm-for-3.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...

Pull power management fixes from Rafael J. Wysocki:
 "Three ACPI device power management fixes related to checking and
  setting device power states."

* tag 'pm-for-3.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / PM: Use KERN_DEBUG when no power resources are found
  ACPI / PM: Fix resource_lock dead lock in acpi_power_on_device
  ACPI / PM: Infer parent power state from child if unknown, v2

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 9628652e080c590fb3f6e01dedc655584c12737b..e0596954290b8e33e20791effc0227b80fb4a0c9 100644 (file)
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -237,6 +237,16 @@ static int __acpi_bus_get_power(struct acpi_device *device, int *state)
        } else if (result == ACPI_STATE_D3_HOT) {
                result = ACPI_STATE_D3;
        }
+
+       /*
+        * If we were unsure about the device parent's power state up to this
+        * point, the fact that the device is in D0 implies that the parent has
+        * to be in D0 too.
+        */
+       if (device->parent && device->parent->power.state == ACPI_STATE_UNKNOWN
+           && result == ACPI_STATE_D0)
+               device->parent->power.state = ACPI_STATE_D0;
+
        *state = result;
 
  out:

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index fc1803414629d8233b0d6f11819efd166838952e..40e38a06ba854fc04751ec2386ca334d01998eb8 100644 (file)
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -107,6 +107,7 @@ struct acpi_power_resource {
 
        /* List of devices relying on this power resource */
        struct acpi_power_resource_device *devices;
+       struct mutex devices_lock;
 };
 
 static struct list_head acpi_power_resource_list;
@@ -225,7 +226,6 @@ static void acpi_power_on_device(struct acpi_power_managed_device *device)
 
 static int __acpi_power_on(struct acpi_power_resource *resource)
 {
-       struct acpi_power_resource_device *device_list = resource->devices;
        acpi_status status = AE_OK;
 
        status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
@@ -238,19 +238,15 @@ static int __acpi_power_on(struct acpi_power_resource *resource)
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
                          resource->name));
 
-       while (device_list) {
-               acpi_power_on_device(device_list->device);
-
-               device_list = device_list->next;
-       }
-
        return 0;
 }
 
 static int acpi_power_on(acpi_handle handle)
 {
        int result = 0;
+       bool resume_device = false;
        struct acpi_power_resource *resource = NULL;
+       struct acpi_power_resource_device *device_list;
 
        result = acpi_power_get_context(handle, &resource);
        if (result)
@@ -266,10 +262,25 @@ static int acpi_power_on(acpi_handle handle)
                result = __acpi_power_on(resource);
                if (result)
                        resource->ref_count--;
+               else
+                       resume_device = true;
        }
 
        mutex_unlock(&resource->resource_lock);
 
+       if (!resume_device)
+               return result;
+
+       mutex_lock(&resource->devices_lock);
+
+       device_list = resource->devices;
+       while (device_list) {
+               acpi_power_on_device(device_list->device);
+               device_list = device_list->next;
+       }
+
+       mutex_unlock(&resource->devices_lock);
+
        return result;
 }
 
@@ -355,7 +366,7 @@ static void __acpi_power_resource_unregister_device(struct device *dev,
        if (acpi_power_get_context(res_handle, &resource))
                return;
 
-       mutex_lock(&resource->resource_lock);
+       mutex_lock(&resource->devices_lock);
        prev = NULL;
        curr = resource->devices;
        while (curr) {
@@ -372,7 +383,7 @@ static void __acpi_power_resource_unregister_device(struct device *dev,
                prev = curr;
                curr = curr->next;
        }
-       mutex_unlock(&resource->resource_lock);
+       mutex_unlock(&resource->devices_lock);
 }
 
 /* Unlink dev from all power resources in _PR0 */
@@ -414,10 +425,10 @@ static int __acpi_power_resource_register_device(
 
        power_resource_device->device = powered_device;
 
-       mutex_lock(&resource->resource_lock);
+       mutex_lock(&resource->devices_lock);
        power_resource_device->next = resource->devices;
        resource->devices = power_resource_device;
-       mutex_unlock(&resource->resource_lock);
+       mutex_unlock(&resource->devices_lock);
 
        return 0;
 }
@@ -462,7 +473,7 @@ int acpi_power_resource_register_device(struct device *dev, acpi_handle handle)
        return ret;
 
 no_power_resource:
-       printk(KERN_WARNING PREFIX "Invalid Power Resource to register!");
+       printk(KERN_DEBUG PREFIX "Invalid Power Resource to register!");
        return -ENODEV;
 }
 EXPORT_SYMBOL_GPL(acpi_power_resource_register_device);
@@ -721,6 +732,7 @@ static int acpi_power_add(struct acpi_device *device)
 
        resource->device = device;
        mutex_init(&resource->resource_lock);
+       mutex_init(&resource->devices_lock);
        strcpy(resource->name, device->pnp.bus_id);
        strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
        strcpy(acpi_device_class(device), ACPI_POWER_CLASS);