1 files changed, 66 insertions, 39 deletions

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 32974b575e46..eba7785047ca 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -52,6 +52,7 @@ struct acpi_power_resource {
 	u32 system_level;
 	u32 order;
 	unsigned int ref_count;
+	u8 state;
 	bool wakeup_enabled;
 	struct mutex resource_lock;
 	struct list_head dependents;
@@ -147,6 +148,7 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 
 	for (i = start; i < package->package.count; i++) {
 		union acpi_object *element = &package->package.elements[i];
+		struct acpi_device *rdev;
 		acpi_handle rhandle;
 
 		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
@@ -163,10 +165,11 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 		if (acpi_power_resource_is_dup(package, start, i))
 			continue;
 
-		err = acpi_add_power_resource(rhandle);
-		if (err)
+		rdev = acpi_add_power_resource(rhandle);
+		if (!rdev) {
+			err = -ENODEV;
 			break;
-
+		}
 		err = acpi_power_resources_list_add(rhandle, list);
 		if (err)
 			break;
@@ -177,44 +180,54 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 	return err;
 }
 
-static int acpi_power_get_state(acpi_handle handle, int *state)
+static int __get_state(acpi_handle handle, u8 *state)
 {
 	acpi_status status = AE_OK;
 	unsigned long long sta = 0;
-
-	if (!handle || !state)
-		return -EINVAL;
+	u8 cur_state;
 
 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 	if (ACPI_FAILURE(status))
 		return -ENODEV;
 
-	*state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
-			      ACPI_POWER_RESOURCE_STATE_OFF;
+	cur_state = sta & ACPI_POWER_RESOURCE_STATE_ON;
 
 	acpi_handle_debug(handle, "Power resource is %s\n",
-			  *state ? "on" : "off");
+			  cur_state ? "on" : "off");
+
+	*state = cur_state;
+	return 0;
+}
+
+static int acpi_power_get_state(struct acpi_power_resource *resource, u8 *state)
+{
+	if (resource->state == ACPI_POWER_RESOURCE_STATE_UNKNOWN) {
+		int ret;
 
+		ret = __get_state(resource->device.handle, &resource->state);
+		if (ret)
+			return ret;
+	}
+
+	*state = resource->state;
 	return 0;
 }
 
-static int acpi_power_get_list_state(struct list_head *list, int *state)
+static int acpi_power_get_list_state(struct list_head *list, u8 *state)
 {
 	struct acpi_power_resource_entry *entry;
-	int cur_state;
+	u8 cur_state = ACPI_POWER_RESOURCE_STATE_OFF;
 
 	if (!list || !state)
 		return -EINVAL;
 
 	/* The state of the list is 'on' IFF all resources are 'on'. */
-	cur_state = 0;
 	list_for_each_entry(entry, list, node) {
 		struct acpi_power_resource *resource = entry->resource;
-		acpi_handle handle = resource->device.handle;
 		int result;
 
 		mutex_lock(&resource->resource_lock);
-		result = acpi_power_get_state(handle, &cur_state);
+		result = acpi_power_get_state(resource, &cur_state);
 		mutex_unlock(&resource->resource_lock);
 		if (result)
 			return result;
@@ -347,8 +360,12 @@ static int __acpi_power_on(struct acpi_power_resource *resource)
 	acpi_status status = AE_OK;
 
 	status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL);
-	if (ACPI_FAILURE(status))
+	if (ACPI_FAILURE(status)) {
+		resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
 		return -ENODEV;
+	}
+
+	resource->state = ACPI_POWER_RESOURCE_STATE_ON;
 
 	pr_debug("Power resource [%s] turned on\n", resource->name);
 
@@ -400,8 +417,12 @@ static int __acpi_power_off(struct acpi_power_resource *resource)
 
 	status = acpi_evaluate_object(resource->device.handle, "_OFF",
 				      NULL, NULL);
-	if (ACPI_FAILURE(status))
+	if (ACPI_FAILURE(status)) {
+		resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
 		return -ENODEV;
+	}
+
+	resource->state = ACPI_POWER_RESOURCE_STATE_OFF;
 
 	pr_debug("Power resource [%s] turned off\n", resource->name);
 
@@ -585,13 +606,12 @@ int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
 
 	list_for_each_entry(entry, list, node) {
 		struct acpi_power_resource *resource = entry->resource;
-		acpi_handle handle = resource->device.handle;
 		int result;
-		int state;
+		u8 state;
 
 		mutex_lock(&resource->resource_lock);
 
-		result = acpi_power_get_state(handle, &state);
+		result = acpi_power_get_state(resource, &state);
 		if (result) {
 			mutex_unlock(&resource->resource_lock);
 			return result;
@@ -784,8 +804,8 @@ int acpi_disable_wakeup_device_power(struct acpi_device *dev)
 
 int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
 {
+	u8 list_state = ACPI_POWER_RESOURCE_STATE_OFF;
 	int result = 0;
-	int list_state = 0;
 	int i = 0;
 
 	if (!device || !state)
@@ -907,22 +927,22 @@ static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource
 	mutex_unlock(&power_resource_list_lock);
 }
 
-int acpi_add_power_resource(acpi_handle handle)
+struct acpi_device *acpi_add_power_resource(acpi_handle handle)
 {
 	struct acpi_power_resource *resource;
 	struct acpi_device *device = NULL;
 	union acpi_object acpi_object;
 	struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
 	acpi_status status;
-	int state, result = -ENODEV;
+	int result;
 
 	acpi_bus_get_device(handle, &device);
 	if (device)
-		return 0;
+		return device;
 
 	resource = kzalloc(sizeof(*resource), GFP_KERNEL);
 	if (!resource)
-		return -ENOMEM;
+		return NULL;
 
 	device = &resource->device;
 	acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER);
@@ -941,13 +961,9 @@ int acpi_add_power_resource(acpi_handle handle)
 
 	resource->system_level = acpi_object.power_resource.system_level;
 	resource->order = acpi_object.power_resource.resource_order;
+	resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
 
-	result = acpi_power_get_state(handle, &state);
-	if (result)
-		goto err;
-
-	pr_info("%s [%s] (%s)\n", acpi_device_name(device),
-		acpi_device_bid(device), state ? "on" : "off");
+	pr_info("%s [%s]\n", acpi_device_name(device), acpi_device_bid(device));
 
 	device->flags.match_driver = true;
 	result = acpi_device_add(device, acpi_release_power_resource);
@@ -959,11 +975,11 @@ int acpi_add_power_resource(acpi_handle handle)
 
 	acpi_power_add_resource_to_list(resource);
 	acpi_device_add_finalize(device);
-	return 0;
+	return device;
 
  err:
 	acpi_release_power_resource(&device->dev);
-	return result;
+	return NULL;
 }
 
 #ifdef CONFIG_ACPI_SLEEP
@@ -974,11 +990,13 @@ void acpi_resume_power_resources(void)
 	mutex_lock(&power_resource_list_lock);
 
 	list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
-		int result, state;
+		int result;
+		u8 state;
 
 		mutex_lock(&resource->resource_lock);
 
-		result = acpi_power_get_state(resource->device.handle, &state);
+		resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
+		result = acpi_power_get_state(resource, &state);
 		if (result) {
 			mutex_unlock(&resource->resource_lock);
 			continue;
@@ -986,7 +1004,7 @@ void acpi_resume_power_resources(void)
 
 		if (state == ACPI_POWER_RESOURCE_STATE_OFF
 		    && resource->ref_count) {
-			dev_info(&resource->device.dev, "Turning ON\n");
+			dev_dbg(&resource->device.dev, "Turning ON\n");
 			__acpi_power_on(resource);
 		}
 
@@ -995,7 +1013,11 @@ void acpi_resume_power_resources(void)
 
 	mutex_unlock(&power_resource_list_lock);
 }
+#endif
 
+/**
+ * acpi_turn_off_unused_power_resources - Turn off power resources not in use.
+ */
 void acpi_turn_off_unused_power_resources(void)
 {
 	struct acpi_power_resource *resource;
@@ -1005,8 +1027,14 @@ void acpi_turn_off_unused_power_resources(void)
 	list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
 		mutex_lock(&resource->resource_lock);
 
-		if (!resource->ref_count) {
-			dev_info(&resource->device.dev, "Turning OFF\n");
+		/*
+		 * Turn off power resources in an unknown state too, because the
+		 * platform firmware on some system expects the OS to turn off
+		 * power resources without any users unconditionally.
+		 */
+		if (!resource->ref_count &&
+		    resource->state != ACPI_POWER_RESOURCE_STATE_OFF) {
+			dev_dbg(&resource->device.dev, "Turning OFF\n");
 			__acpi_power_off(resource);
 		}
 
@@ -1015,4 +1043,3 @@ void acpi_turn_off_unused_power_resources(void)
 
 	mutex_unlock(&power_resource_list_lock);
 }
-#endif