Merge branches 'acpi-bus', 'acpi-scan' and 'acpi-tables'

* acpi-bus:
  ACPI: Remove redundant clearing of context->ret.pointer from acpi_run_osc()

* acpi-scan:
  ACPI: scan: Simplify acpi_table_events_fn()
  ACPI: scan: Fix race related to dropping dependencies
  ACPI: scan: Reorganize acpi_device_add()
  ACPI: scan: Fix device object rescan in acpi_scan_clear_dep()
  ACPI: scan: Make acpi_walk_dep_device_list()
  ACPI: scan: Rearrange acpi_dev_get_first_consumer_dev_cb()
  ACPI: scan: Define acpi_bus_put_acpi_device() as static inline
  ACPI: scan: initialize local variable to avoid garbage being returned
  ACPI: scan: Add function to fetch dependent of ACPI device
  ACPI: scan: Extend acpi_walk_dep_device_list()
  ACPI: scan: Rearrange dep_unmet initialization

* acpi-tables:
  ACPI: tables: Add custom DSDT file as makefile prerequisite
  ACPI: bgrt: Use sysfs_emit
  ACPI: bgrt: Fix CFI violation
  ACPI: tables: FPDT: Add missing acpi_put_table() in acpi_init_fpdt()
  ACPI: tables: PPTT: Populate cache-id if provided by firmware

drivers/acpi/Makefile

@@ -8,6 +8,11 @@ ccflags-$(CONFIG_ACPI_DEBUG)	+= -DACPI_DEBUG_OUTPUT
 #
 # ACPI Boot-Time Table Parsing
 #
+ifeq ($(CONFIG_ACPI_CUSTOM_DSDT),y)
+tables.o: $(src)/../../include/$(subst $\",,$(CONFIG_ACPI_CUSTOM_DSDT_FILE)) ;
+
+endif
+
 obj-$(CONFIG_ACPI)		+= tables.o
 obj-$(CONFIG_X86)		+= blacklist.o
 

drivers/acpi/acpi_fpdt.c

@@ -240,8 +240,10 @@ static int __init acpi_init_fpdt(void)
 		return 0;
 
 	fpdt_kobj = kobject_create_and_add("fpdt", acpi_kobj);
-	if (!fpdt_kobj)
+	if (!fpdt_kobj) {
+		acpi_put_table(header);
 		return -ENOMEM;
+	}
 
 	while (offset < header->length) {
 		subtable = (void *)header + offset;

drivers/acpi/bgrt.c

@@ -15,40 +15,19 @@
 static void *bgrt_image;
 static struct kobject *bgrt_kobj;
 
-static ssize_t version_show(struct device *dev,
-			    struct device_attribute *attr, char *buf)
-{
-	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.version);
-}
-static DEVICE_ATTR_RO(version);
-
-static ssize_t status_show(struct device *dev,
-			   struct device_attribute *attr, char *buf)
-{
-	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.status);
-}
-static DEVICE_ATTR_RO(status);
-
-static ssize_t type_show(struct device *dev,
-			 struct device_attribute *attr, char *buf)
-{
-	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.image_type);
-}
-static DEVICE_ATTR_RO(type);
-
-static ssize_t xoffset_show(struct device *dev,
-			    struct device_attribute *attr, char *buf)
-{
-	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.image_offset_x);
-}
-static DEVICE_ATTR_RO(xoffset);
-
-static ssize_t yoffset_show(struct device *dev,
-			    struct device_attribute *attr, char *buf)
-{
-	return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.image_offset_y);
-}
-static DEVICE_ATTR_RO(yoffset);
+#define BGRT_SHOW(_name, _member) \
+	static ssize_t _name##_show(struct kobject *kobj,			\
+				    struct kobj_attribute *attr, char *buf)	\
+	{									\
+		return sysfs_emit(buf, "%d\n", bgrt_tab._member);		\
+	}									\
+	struct kobj_attribute bgrt_attr_##_name = __ATTR_RO(_name)
+
+BGRT_SHOW(version, version);
+BGRT_SHOW(status, status);
+BGRT_SHOW(type, image_type);
+BGRT_SHOW(xoffset, image_offset_x);
+BGRT_SHOW(yoffset, image_offset_y);
 
 static ssize_t image_read(struct file *file, struct kobject *kobj,
 	       struct bin_attribute *attr, char *buf, loff_t off, size_t count)
@@ -60,11 +39,11 @@ static ssize_t image_read(struct file *file, struct kobject *kobj,
 static BIN_ATTR_RO(image, 0);	/* size gets filled in later */
 
 static struct attribute *bgrt_attributes[] = {
-	&dev_attr_version.attr,
-	&dev_attr_status.attr,
-	&dev_attr_type.attr,
-	&dev_attr_xoffset.attr,
-	&dev_attr_yoffset.attr,
+	&bgrt_attr_version.attr,
+	&bgrt_attr_status.attr,
+	&bgrt_attr_type.attr,
+	&bgrt_attr_xoffset.attr,
+	&bgrt_attr_yoffset.attr,
 	NULL,
 };
 

drivers/acpi/bus.c

@@ -262,8 +262,6 @@ acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
 
 out_kfree:
 	kfree(output.pointer);
-	if (status != AE_OK)
-		context->ret.pointer = NULL;
 	return status;
 }
 EXPORT_SYMBOL(acpi_run_osc);
@@ -1195,7 +1193,8 @@ void __init acpi_subsystem_init(void)
 
 static acpi_status acpi_bus_table_handler(u32 event, void *table, void *context)
 {
-	acpi_scan_table_handler(event, table, context);
+	if (event == ACPI_TABLE_EVENT_LOAD)
+		acpi_scan_table_notify();
 
 	return acpi_sysfs_table_handler(event, table, context);
 }

drivers/acpi/ec.c

@@ -1627,7 +1627,7 @@ static int acpi_ec_add(struct acpi_device *device)
 	WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 
 	/* Reprobe devices depending on the EC */
-	acpi_walk_dep_device_list(ec->handle);
+	acpi_dev_clear_dependencies(device);
 
 	acpi_handle_debug(ec->handle, "enumerated.\n");
 	return 0;

drivers/acpi/internal.h

@@ -88,7 +88,7 @@ void acpi_device_hotplug(struct acpi_device *adev, u32 src);
 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent);
 
 acpi_status acpi_sysfs_table_handler(u32 event, void *table, void *context);
-void acpi_scan_table_handler(u32 event, void *table, void *context);
+void acpi_scan_table_notify(void);
 
 /* --------------------------------------------------------------------------
                      Device Node Initialization / Removal

drivers/acpi/pmic/intel_pmic_chtdc_ti.c

@@ -117,7 +117,7 @@ static int chtdc_ti_pmic_opregion_probe(struct platform_device *pdev)
 		return err;
 
 	/* Re-enumerate devices depending on PMIC */
-	acpi_walk_dep_device_list(ACPI_HANDLE(pdev->dev.parent));
+	acpi_dev_clear_dependencies(ACPI_COMPANION(pdev->dev.parent));
 	return 0;
 }
 

drivers/acpi/pptt.c

@@ -347,6 +347,7 @@ static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *ta
  * @this_leaf: Kernel cache info structure being updated
  * @found_cache: The PPTT node describing this cache instance
  * @cpu_node: A unique reference to describe this cache instance
+ * @revision: The revision of the PPTT table
  *
  * The ACPI spec implies that the fields in the cache structures are used to
  * extend and correct the information probed from the hardware. Lets only
@@ -356,8 +357,11 @@ static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *ta
  */
 static void update_cache_properties(struct cacheinfo *this_leaf,
 				    struct acpi_pptt_cache *found_cache,
-				    struct acpi_pptt_processor *cpu_node)
+				    struct acpi_pptt_processor *cpu_node,
+				    u8 revision)
 {
+	struct acpi_pptt_cache_v1* found_cache_v1;
+
 	this_leaf->fw_token = cpu_node;
 	if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID)
 		this_leaf->size = found_cache->size;
@@ -405,6 +409,13 @@ static void update_cache_properties(struct cacheinfo *this_leaf,
 	if (this_leaf->type == CACHE_TYPE_NOCACHE &&
 	    found_cache->flags & ACPI_PPTT_CACHE_TYPE_VALID)
 		this_leaf->type = CACHE_TYPE_UNIFIED;
+
+	if (revision >= 3 && (found_cache->flags & ACPI_PPTT_CACHE_ID_VALID)) {
+		found_cache_v1 = ACPI_ADD_PTR(struct acpi_pptt_cache_v1,
+	                                      found_cache, sizeof(struct acpi_pptt_cache));
+		this_leaf->id = found_cache_v1->cache_id;
+		this_leaf->attributes |= CACHE_ID;
+	}
 }
 
 static void cache_setup_acpi_cpu(struct acpi_table_header *table,
@@ -425,9 +436,8 @@ static void cache_setup_acpi_cpu(struct acpi_table_header *table,
 						   &cpu_node);
 		pr_debug("found = %p %p\n", found_cache, cpu_node);
 		if (found_cache)
-			update_cache_properties(this_leaf,
-						found_cache,
-						cpu_node);
+			update_cache_properties(this_leaf, found_cache,
+			                        cpu_node, table->revision);
 
 		index++;
 	}

drivers/acpi/scan.c

@@ -47,12 +47,6 @@ static DEFINE_MUTEX(acpi_hp_context_lock);
  */
 static u64 spcr_uart_addr;
 
-struct acpi_dep_data {
-	struct list_head node;
-	acpi_handle supplier;
-	acpi_handle consumer;
-};
-
 void acpi_scan_lock_acquire(void)
 {
 	mutex_lock(&acpi_scan_lock);
@@ -612,11 +606,6 @@ struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
 	return handle_to_device(handle, get_acpi_device);
 }
 
-void acpi_bus_put_acpi_device(struct acpi_device *adev)
-{
-	acpi_dev_put(adev);
-}
-
 static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id)
 {
 	struct acpi_device_bus_id *acpi_device_bus_id;
@@ -644,24 +633,29 @@ static int acpi_device_set_name(struct acpi_device *device,
 	return 0;
 }
 
-int acpi_device_add(struct acpi_device *device,
-		    void (*release)(struct device *))
+static int acpi_tie_acpi_dev(struct acpi_device *adev)
 {
-	struct acpi_device_bus_id *acpi_device_bus_id;
-	int result;
+	acpi_handle handle = adev->handle;
+	acpi_status status;
 
-	if (device->handle) {
-		acpi_status status;
+	if (!handle)
+		return 0;
 
-		status = acpi_attach_data(device->handle, acpi_scan_drop_device,
-					  device);
-		if (ACPI_FAILURE(status)) {
-			acpi_handle_err(device->handle,
-					"Unable to attach device data\n");
-			return -ENODEV;
-		}
+	status = acpi_attach_data(handle, acpi_scan_drop_device, adev);
+	if (ACPI_FAILURE(status)) {
+		acpi_handle_err(handle, "Unable to attach device data\n");
+		return -ENODEV;
 	}
 
+	return 0;
+}
+
+static int __acpi_device_add(struct acpi_device *device,
+			     void (*release)(struct device *))
+{
+	struct acpi_device_bus_id *acpi_device_bus_id;
+	int result;
+
 	/*
 	 * Linkage
 	 * -------
@@ -750,6 +744,17 @@ int acpi_device_add(struct acpi_device *device,
 	return result;
 }
 
+int acpi_device_add(struct acpi_device *adev, void (*release)(struct device *))
+{
+	int ret;
+
+	ret = acpi_tie_acpi_dev(adev);
+	if (ret)
+		return ret;
+
+	return __acpi_device_add(adev, release);
+}
+
 /* --------------------------------------------------------------------------
                                  Device Enumeration
    -------------------------------------------------------------------------- */
@@ -1671,8 +1676,16 @@ 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;
+
+	list_for_each_entry(dep, &acpi_dep_list, node) {
+		if (dep->consumer == adev->handle)
+			adev->dep_unmet++;
+	}
 }
 
 void acpi_device_add_finalize(struct acpi_device *device)
@@ -1688,9 +1701,10 @@ 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;
+	bool release_dep_lock = false;
 	int result;
 
 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
@@ -1703,13 +1717,32 @@ 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) {
+			mutex_lock(&acpi_dep_list_lock);
+			/*
+			 * Hold the lock until the acpi_tie_acpi_dev() call
+			 * below to prevent concurrent acpi_scan_clear_dep()
+			 * from deleting a dependency list entry without
+			 * updating dep_unmet for the device.
+			 */
+			release_dep_lock = true;
+			acpi_scan_dep_init(device);
+		}
 		acpi_scan_init_status(device);
+	}
 
 	acpi_bus_get_power_flags(device);
 	acpi_bus_get_wakeup_device_flags(device);
 
-	result = acpi_device_add(device, acpi_device_release);
+	result = acpi_tie_acpi_dev(device);
+
+	if (release_dep_lock)
+		mutex_unlock(&acpi_dep_list_lock);
+
+	if (!result)
+		result = __acpi_device_add(device, acpi_device_release);
+
 	if (result) {
 		acpi_device_release(&device->dev);
 		return result;
@@ -1886,22 +1919,6 @@ 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 +1966,15 @@ 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)
@@ -2111,29 +2124,141 @@ static void acpi_bus_attach(struct acpi_device *device, bool first_pass)
 		device->handler->hotplug.notify_online(device);
 }
 
-void acpi_walk_dep_device_list(acpi_handle handle)
+static int acpi_dev_get_first_consumer_dev_cb(struct acpi_dep_data *dep, void *data)
 {
-	struct acpi_dep_data *dep, *tmp;
 	struct acpi_device *adev;
 
+	adev = acpi_bus_get_acpi_device(dep->consumer);
+	if (adev) {
+		*(struct acpi_device **)data = adev;
+		return 1;
+	}
+	/* Continue parsing if the device object is not present. */
+	return 0;
+}
+
+struct acpi_scan_clear_dep_work {
+	struct work_struct work;
+	struct acpi_device *adev;
+};
+
+static void acpi_scan_clear_dep_fn(struct work_struct *work)
+{
+	struct acpi_scan_clear_dep_work *cdw;
+
+	cdw = container_of(work, struct acpi_scan_clear_dep_work, work);
+
+	acpi_scan_lock_acquire();
+	acpi_bus_attach(cdw->adev, true);
+	acpi_scan_lock_release();
+
+	acpi_dev_put(cdw->adev);
+	kfree(cdw);
+}
+
+static bool acpi_scan_clear_dep_queue(struct acpi_device *adev)
+{
+	struct acpi_scan_clear_dep_work *cdw;
+
+	if (adev->dep_unmet)
+		return false;
+
+	cdw = kmalloc(sizeof(*cdw), GFP_KERNEL);
+	if (!cdw)
+		return false;
+
+	cdw->adev = adev;
+	INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn);
+	/*
+	 * Since the work function may block on the lock until the entire
+	 * initial enumeration of devices is complete, put it into the unbound
+	 * workqueue.
+	 */
+	queue_work(system_unbound_wq, &cdw->work);
+
+	return true;
+}
+
+static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
+{
+	struct acpi_device *adev = acpi_bus_get_acpi_device(dep->consumer);
+
+	if (adev) {
+		adev->dep_unmet--;
+		if (!acpi_scan_clear_dep_queue(adev))
+			acpi_dev_put(adev);
+	}
+
+	list_del(&dep->node);
+	kfree(dep);
+
+	return 0;
+}
+
+/**
+ * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
+ * @handle:	The ACPI handle of the supplier device
+ * @callback:	Pointer to the callback function to apply
+ * @data:	Pointer to some data to pass to the callback
+ *
+ * The return value of the callback determines this function's behaviour. If 0
+ * is returned we continue to iterate over acpi_dep_list. If a positive value
+ * is returned then the loop is broken but this function returns 0. If a
+ * negative value is returned by the callback then the loop is broken and that
+ * value is returned as the final error.
+ */
+static int acpi_walk_dep_device_list(acpi_handle handle,
+				int (*callback)(struct acpi_dep_data *, void *),
+				void *data)
+{
+	struct acpi_dep_data *dep, *tmp;
+	int ret = 0;
+
 	mutex_lock(&acpi_dep_list_lock);
 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
 		if (dep->supplier == handle) {
-			acpi_bus_get_device(dep->consumer, &adev);
-
-			if (adev) {
-				adev->dep_unmet--;
-				if (!adev->dep_unmet)
-					acpi_bus_attach(adev, true);
-			}
-
-			list_del(&dep->node);
-			kfree(dep);
+			ret = callback(dep, data);
+			if (ret)
+				break;
 		}
 	}
 	mutex_unlock(&acpi_dep_list_lock);
+
+	return ret > 0 ? 0 : ret;
+}
+
+/**
+ * acpi_dev_clear_dependencies - Inform consumers that the device is now active
+ * @supplier: Pointer to the supplier &struct acpi_device
+ *
+ * Clear dependencies on the given device.
+ */
+void acpi_dev_clear_dependencies(struct acpi_device *supplier)
+{
+	acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
+
+/**
+ * acpi_dev_get_first_consumer_dev - Return ACPI device dependent on @supplier
+ * @supplier: Pointer to the dependee device
+ *
+ * Returns the first &struct acpi_device which declares itself dependent on
+ * @supplier via the _DEP buffer, parsed from the acpi_dep_list.
+ *
+ * The caller is responsible for putting the reference to adev when it is no
+ * longer needed.
+ */
+struct acpi_device *acpi_dev_get_first_consumer_dev(struct acpi_device *supplier)
+{
+	struct acpi_device *adev = NULL;
+
+	acpi_walk_dep_device_list(supplier->handle,
+				  acpi_dev_get_first_consumer_dev_cb, &adev);
+
+	return adev;
 }
-EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
+EXPORT_SYMBOL_GPL(acpi_dev_get_first_consumer_dev);
 
 /**
  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
@@ -2223,7 +2348,7 @@ 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 +2368,7 @@ 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 +2384,7 @@ 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;
 
@@ -2408,46 +2533,28 @@ int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
 	return count;
 }
 
-struct acpi_table_events_work {
-	struct work_struct work;
-	void *table;
-	u32 event;
-};
-
 static void acpi_table_events_fn(struct work_struct *work)
 {
-	struct acpi_table_events_work *tew;
+	acpi_scan_lock_acquire();
+	acpi_bus_scan(ACPI_ROOT_OBJECT);
+	acpi_scan_lock_release();
 
-	tew = container_of(work, struct acpi_table_events_work, work);
-
-	if (tew->event == ACPI_TABLE_EVENT_LOAD) {
-		acpi_scan_lock_acquire();
-		acpi_bus_scan(ACPI_ROOT_OBJECT);
-		acpi_scan_lock_release();
-	}
-
-	kfree(tew);
+	kfree(work);
 }
 
-void acpi_scan_table_handler(u32 event, void *table, void *context)
+void acpi_scan_table_notify(void)
 {
-	struct acpi_table_events_work *tew;
+	struct work_struct *work;
 
 	if (!acpi_scan_initialized)
 		return;
 
-	if (event != ACPI_TABLE_EVENT_LOAD)
-		return;
-
-	tew = kmalloc(sizeof(*tew), GFP_KERNEL);
-	if (!tew)
+	work = kmalloc(sizeof(*work), GFP_KERNEL);
+	if (!work)
 		return;
 
-	INIT_WORK(&tew->work, acpi_table_events_fn);
-	tew->table = table;
-	tew->event = event;
-
-	schedule_work(&tew->work);
+	INIT_WORK(work, acpi_table_events_fn);
+	schedule_work(work);
 }
 
 int acpi_reconfig_notifier_register(struct notifier_block *nb)

drivers/gpio/gpiolib-acpi.c

@@ -1233,14 +1233,14 @@ static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
 void acpi_gpiochip_add(struct gpio_chip *chip)
 {
 	struct acpi_gpio_chip *acpi_gpio;
-	acpi_handle handle;
+	struct acpi_device *adev;
 	acpi_status status;
 
 	if (!chip || !chip->parent)
 		return;
 
-	handle = ACPI_HANDLE(chip->parent);
-	if (!handle)
+	adev = ACPI_COMPANION(chip->parent);
+	if (!adev)
 		return;
 
 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
@@ -1254,7 +1254,7 @@ void acpi_gpiochip_add(struct gpio_chip *chip)
 	INIT_LIST_HEAD(&acpi_gpio->events);
 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
 
-	status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
+	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
 	if (ACPI_FAILURE(status)) {
 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
 		kfree(acpi_gpio);
@@ -1263,7 +1263,7 @@ void acpi_gpiochip_add(struct gpio_chip *chip)
 
 	acpi_gpiochip_request_regions(acpi_gpio);
 	acpi_gpiochip_scan_gpios(acpi_gpio);
-	acpi_walk_dep_device_list(handle);
+	acpi_dev_clear_dependencies(adev);
 }
 
 void acpi_gpiochip_remove(struct gpio_chip *chip)

drivers/i2c/i2c-core-acpi.c

@@ -259,8 +259,8 @@ static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
  */
 void i2c_acpi_register_devices(struct i2c_adapter *adap)
 {
+	struct acpi_device *adev;
 	acpi_status status;
-	acpi_handle handle;
 
 	if (!has_acpi_companion(&adap->dev))
 		return;
@@ -275,11 +275,11 @@ void i2c_acpi_register_devices(struct i2c_adapter *adap)
 	if (!adap->dev.parent)
 		return;
 
-	handle = ACPI_HANDLE(adap->dev.parent);
-	if (!handle)
+	adev = ACPI_COMPANION(adap->dev.parent);
+	if (!adev)
 		return;
 
-	acpi_walk_dep_device_list(handle);
+	acpi_dev_clear_dependencies(adev);
 }
 
 static const struct acpi_device_id i2c_acpi_force_400khz_device_ids[] = {

drivers/platform/surface/aggregator/core.c

@@ -621,8 +621,8 @@ static const struct acpi_gpio_mapping ssam_acpi_gpios[] = {
 
 static int ssam_serial_hub_probe(struct serdev_device *serdev)
 {
+	struct acpi_device *ssh = ACPI_COMPANION(&serdev->dev);
 	struct ssam_controller *ctrl;
-	acpi_handle *ssh = ACPI_HANDLE(&serdev->dev);
 	acpi_status astatus;
 	int status;
 
@@ -652,7 +652,7 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev)
 	if (status)
 		goto err_devopen;
 
-	astatus = ssam_serdev_setup_via_acpi(ssh, serdev);
+	astatus = ssam_serdev_setup_via_acpi(ssh->handle, serdev);
 	if (ACPI_FAILURE(astatus)) {
 		status = -ENXIO;
 		goto err_devinit;
@@ -706,7 +706,7 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev)
 	 *       For now let's thus default power/wakeup to false.
 	 */
 	device_set_wakeup_capable(&serdev->dev, true);
-	acpi_walk_dep_device_list(ssh);
+	acpi_dev_clear_dependencies(ssh);
 
 	return 0;
 

drivers/platform/surface/surface3_power.c

@@ -446,12 +446,12 @@ mshw0011_space_handler(u32 function, acpi_physical_address command,
 
 static int mshw0011_install_space_handler(struct i2c_client *client)
 {
-	acpi_handle handle;
+	struct acpi_device *adev;
 	struct mshw0011_handler_data *data;
 	acpi_status status;
 
-	handle = ACPI_HANDLE(&client->dev);
-	if (!handle)
+	adev = ACPI_COMPANION(&client->dev);
+	if (!adev)
 		return -ENODEV;
 
 	data = kzalloc(sizeof(struct mshw0011_handler_data),
@@ -460,25 +460,25 @@ static int mshw0011_install_space_handler(struct i2c_client *client)
 		return -ENOMEM;
 
 	data->client = client;
-	status = acpi_bus_attach_private_data(handle, (void *)data);
+	status = acpi_bus_attach_private_data(adev->handle, (void *)data);
 	if (ACPI_FAILURE(status)) {
 		kfree(data);
 		return -ENOMEM;
 	}
 
-	status = acpi_install_address_space_handler(handle,
-				ACPI_ADR_SPACE_GSBUS,
-				&mshw0011_space_handler,
-				NULL,
-				data);
+	status = acpi_install_address_space_handler(adev->handle,
+						    ACPI_ADR_SPACE_GSBUS,
+						    &mshw0011_space_handler,
+						    NULL,
+						    data);
 	if (ACPI_FAILURE(status)) {
 		dev_err(&client->dev, "Error installing i2c space handler\n");
-		acpi_bus_detach_private_data(handle);
+		acpi_bus_detach_private_data(adev->handle);
 		kfree(data);
 		return -ENOMEM;
 	}
 
-	acpi_walk_dep_device_list(handle);
+	acpi_dev_clear_dependencies(adev);
 	return 0;
 }
 

drivers/platform/surface/surface_acpi_notify.c

@@ -798,7 +798,7 @@ static int san_consumer_links_setup(struct platform_device *pdev)
 
 static int san_probe(struct platform_device *pdev)
 {
-	acpi_handle san = ACPI_HANDLE(&pdev->dev);
+	struct acpi_device *san = ACPI_COMPANION(&pdev->dev);
 	struct ssam_controller *ctrl;
 	struct san_data *data;
 	acpi_status astatus;
@@ -821,7 +821,8 @@ static int san_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, data);
 
-	astatus = acpi_install_address_space_handler(san, ACPI_ADR_SPACE_GSBUS,
+	astatus = acpi_install_address_space_handler(san->handle,
+						     ACPI_ADR_SPACE_GSBUS,
 						     &san_opreg_handler, NULL,
 						     &data->info);
 	if (ACPI_FAILURE(astatus))
@@ -835,7 +836,7 @@ static int san_probe(struct platform_device *pdev)
 	if (status)
 		goto err_install_dev;
 
-	acpi_walk_dep_device_list(san);
+	acpi_dev_clear_dependencies(san);
 	return 0;
 
 err_install_dev:

include/acpi/acpi_bus.h

@@ -280,6 +280,12 @@ struct acpi_device_power {
 	struct acpi_device_power_state states[ACPI_D_STATE_COUNT];	/* Power states (D0-D3Cold) */
 };
 
+struct acpi_dep_data {
+	struct list_head node;
+	acpi_handle supplier;
+	acpi_handle consumer;
+};
+
 /* Performance Management */
 
 struct acpi_device_perf_flags {
@@ -498,8 +504,6 @@ extern int unregister_acpi_notifier(struct notifier_block *);
  */
 
 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device);
-struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle);
-void acpi_bus_put_acpi_device(struct acpi_device *adev);
 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
 				       unsigned long long *sta);
 int acpi_bus_get_status(struct acpi_device *device);
@@ -685,6 +689,8 @@ static inline bool acpi_device_can_poweroff(struct acpi_device *adev)
 
 bool acpi_dev_hid_uid_match(struct acpi_device *adev, const char *hid2, const char *uid2);
 
+void acpi_dev_clear_dependencies(struct acpi_device *supplier);
+struct acpi_device *acpi_dev_get_first_consumer_dev(struct acpi_device *supplier);
 struct acpi_device *
 acpi_dev_get_next_match_dev(struct acpi_device *adev, const char *hid, const char *uid, s64 hrv);
 struct acpi_device *
@@ -718,6 +724,13 @@ static inline void acpi_dev_put(struct acpi_device *adev)
 {
 	put_device(&adev->dev);
 }
+
+struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle);
+
+static inline void acpi_bus_put_acpi_device(struct acpi_device *adev)
+{
+	acpi_dev_put(adev);
+}
 #else	/* CONFIG_ACPI */
 
 static inline int register_acpi_bus_type(void *bus) { return 0; }

include/linux/acpi.h

@@ -666,7 +666,6 @@ extern bool acpi_driver_match_device(struct device *dev,
 				     const struct device_driver *drv);
 int acpi_device_uevent_modalias(struct device *, struct kobj_uevent_env *);
 int acpi_device_modalias(struct device *, char *, int);
-void acpi_walk_dep_device_list(acpi_handle handle);
 
 struct platform_device *acpi_create_platform_device(struct acpi_device *,
 						    struct property_entry *);