[PATCH v3 0/9] PM / Domains: Generic OF-based support

@@ -1055,6 +1055,8 @@ static struct dev_pm_domain acpi_general_pm_domain = {
  *
  * Callers must ensure proper synchronization of this function with power
  * management callbacks.
+ *
+ * Returns 0 on successfully attached PM domain or negative error code.
  */
 int acpi_dev_pm_attach(struct device *dev, bool power_on)
 {

@@ -1087,8 +1089,10 @@ EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
  *
  * Callers must ensure proper synchronization of this function with power
  * management callbacks.
+ *
+ * Returns 0 on successfully detached PM domain or negative error code.
  */
-void acpi_dev_pm_detach(struct device *dev, bool power_off)
+int acpi_dev_pm_detach(struct device *dev, bool power_off)
 {
 	struct acpi_device *adev = ACPI_COMPANION(dev);
 

@@ -1107,7 +1111,9 @@ void acpi_dev_pm_detach(struct device *dev, bool power_off)
 			acpi_device_wakeup(adev, ACPI_STATE_S0, false);
 			acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
 		}
+		return 0;
 	}
+	return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(acpi_dev_pm_detach);
 #endif /* CONFIG_PM */

@@ -587,7 +587,7 @@ static inline int acpi_subsys_freeze(struct device *dev) { return 0; }
 #if defined(CONFIG_ACPI) && defined(CONFIG_PM)
 struct acpi_device *acpi_dev_pm_get_node(struct device *dev);
 int acpi_dev_pm_attach(struct device *dev, bool power_on);
-void acpi_dev_pm_detach(struct device *dev, bool power_off);
+int acpi_dev_pm_detach(struct device *dev, bool power_off);
 #else
 static inline struct acpi_device *acpi_dev_pm_get_node(struct device *dev)
 {

@@ -597,7 +597,10 @@ static inline int acpi_dev_pm_attach(struct device *dev, bool power_on)
 {
 	return -ENODEV;
 }
-static inline void acpi_dev_pm_detach(struct device *dev, bool power_off) {}
+static inline int acpi_dev_pm_detach(struct device *dev, bool power_off)
+{
+	return -ENODEV;
+}
 #endif
 
 #ifdef CONFIG_ACPI

@@ -0,0 +1,49 @@
+* Generic PM domains
+
+System on chip designs are often divided into multiple PM domains that can be
+used for power gating of selected IP blocks for power saving by reduced leakage
+current.
+
+This device tree binding can be used to bind PM domain consumer devices with
+their PM domains provided by PM domain providers. A PM domain provider can be
+represented by any node in the device tree and can provide one or more PM
+domains. A consumer node can refer to the provider by a phandle and a set of
+phandle arguments (so called PM domain specifiers) of length specified by the
+#power-domain-cells property in the PM domain provider node.
+
+==PM domain providers==
+
+Required properties:
+ - #power-domain-cells : Number of cells in a PM domain specifier;
+   Typically 0 for nodes representing a single PM domain and 1 for nodes
+   providing multiple PM domains (e.g. power controllers), but can be any value
+   as specified by device tree binding documentation of particular provider.
+
+Example:
+
+	power: power-controller at 12340000 {
+		compatible = "foo,power-controller";
+		reg = <0x12340000 0x1000>;
+		#power-domain-cells = <1>;
+	};
+
+The node above defines a power controller that is a PM domain provider and
+expects one cell as its phandle argument.
+
+==PM domain consumers==
+
+Required properties:
+ - power-domains : A phandle and PM domain specifier as defined by bindings of
+                   the power controller specified by phandle.
+
+Example:
+
+	leaky-device at 12350000 {
+		compatible = "foo,i-leak-current";
+		reg = <0x12350000 0x1000>;
+		power-domains = <&power 0>;
+	};
+
+The node above defines a typical PM domain consumer device, which is located
+inside a PM domain with index 0 of a power controller represented by a node
+with the label "power".

@@ -8,6 +8,7 @@
 
 #include <linux/kernel.h>
 #include <linux/io.h>
+#include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_qos.h>

@@ -2189,3 +2190,293 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
 	list_add(&genpd->gpd_list_node, &gpd_list);
 	mutex_unlock(&gpd_list_lock);
 }
+
+#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
+/*
+ * Device Tree based PM domain providers.
+ *
+ * The code below implements generic device tree based PM domain providers that
+ * bind device tree nodes with generic PM domains registered in the system.
+ *
+ * Any driver that registers generic PM domains and needs to support binding of
+ * devices to these domains is supposed to register a PM domain provider, which
+ * maps a PM domain specifier retrieved from the device tree to a PM domain.
+ *
+ * Two simple mapping functions have been provided for convenience:
+ *  - __of_genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
+ *  - __of_genpd_xlate_onecell() for mapping of multiple PM domains per node by
+ *    index.
+ */
+
+/**
+ * struct of_genpd_provider - PM domain provider registration structure
+ * @link: Entry in global list of PM domain providers
+ * @node: Pointer to device tree node of PM domain provider
+ * @xlate: Provider-specific xlate callback mapping a set of specifier cells
+ *         into a PM domain.
+ * @data: context pointer to be passed into @xlate callback
+ */
+struct of_genpd_provider {
+	struct list_head link;
+	struct device_node *node;
+	genpd_xlate_t xlate;
+	void *data;
+};
+
+/* List of registered PM domain providers. */
+static LIST_HEAD(of_genpd_providers);
+/* Mutex to protect the list above. */
+static DEFINE_MUTEX(of_genpd_mutex);
+
+/**
+ * __of_genpd_xlate_simple() - Xlate function for direct node-domain mapping
+ * @genpdspec: OF phandle args to map into a PM domain
+ * @data: xlate function private data - pointer to struct generic_pm_domain
+ *
+ * This is a generic xlate function that can be used to model PM domains that
+ * have their own device tree nodes. The private data of xlate function needs
+ * to be a valid pointer to struct generic_pm_domain.
+ */
+struct generic_pm_domain *__of_genpd_xlate_simple(
+					struct of_phandle_args *genpdspec,
+					void *data)
+{
+	if (genpdspec->args_count != 0)
+		return ERR_PTR(-EINVAL);
+	return data;
+}
+EXPORT_SYMBOL_GPL(__of_genpd_xlate_simple);
+
+/**
+ * __of_genpd_xlate_onecell() - Xlate function using a single index.
+ * @genpdspec: OF phandle args to map into a PM domain
+ * @data: xlate function private data - pointer to struct genpd_onecell_data
+ *
+ * This is a generic xlate function that can be used to model simple PM domain
+ * controllers that have one device tree node and provide multiple PM domains.
+ * A single cell is used as an index into an array of PM domains specified in
+ * the genpd_onecell_data struct when registering the provider.
+ */
+struct generic_pm_domain *__of_genpd_xlate_onecell(
+					struct of_phandle_args *genpdspec,
+					void *data)
+{
+	struct genpd_onecell_data *genpd_data = data;
+	unsigned int idx = genpdspec->args[0];
+
+	if (genpdspec->args_count != 1)
+		return ERR_PTR(-EINVAL);
+
+	if (idx >= genpd_data->num_domains) {
+		pr_err("%s: invalid domain index %u\n", __func__, idx);
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (!genpd_data->domains[idx])
+		return ERR_PTR(-ENOENT);
+
+	return genpd_data->domains[idx];
+}
+EXPORT_SYMBOL_GPL(__of_genpd_xlate_onecell);
+
+/**
+ * __of_genpd_add_provider() - Register a PM domain provider for a node
+ * @np: Device node pointer associated with the PM domain provider.
+ * @xlate: Callback for decoding PM domain from phandle arguments.
+ * @data: Context pointer for @xlate callback.
+ */
+int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
+			void *data)
+{
+	struct of_genpd_provider *cp;
+
+	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+	if (!cp)
+		return -ENOMEM;
+
+	cp->node = of_node_get(np);
+	cp->data = data;
+	cp->xlate = xlate;
+
+	mutex_lock(&of_genpd_mutex);
+	list_add(&cp->link, &of_genpd_providers);
+	mutex_unlock(&of_genpd_mutex);
+	pr_debug("Added domain provider from %s\n", np->full_name);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__of_genpd_add_provider);
+
+/**
+ * of_genpd_del_provider() - Remove a previously registered PM domain provider
+ * @np: Device node pointer associated with the PM domain provider
+ */
+void of_genpd_del_provider(struct device_node *np)
+{
+	struct of_genpd_provider *cp;
+
+	mutex_lock(&of_genpd_mutex);
+	list_for_each_entry(cp, &of_genpd_providers, link) {
+		if (cp->node == np) {
+			list_del(&cp->link);
+			of_node_put(cp->node);
+			kfree(cp);
+			break;
+		}
+	}
+	mutex_unlock(&of_genpd_mutex);
+}
+EXPORT_SYMBOL_GPL(of_genpd_del_provider);
+
+/**
+ * of_genpd_get_from_provider() - Look-up PM domain
+ * @genpdspec: OF phandle args to use for look-up
+ *
+ * Looks for a PM domain provider under the node specified by @genpdspec and if
+ * found, uses xlate function of the provider to map phandle args to a PM
+ * domain.
+ *
+ * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
+ * on failure.
+ */
+static struct generic_pm_domain *of_genpd_get_from_provider(
+					struct of_phandle_args *genpdspec)
+{
+	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
+	struct of_genpd_provider *provider;
+
+	mutex_lock(&of_genpd_mutex);
+
+	/* Check if we have such a provider in our array */
+	list_for_each_entry(provider, &of_genpd_providers, link) {
+		if (provider->node == genpdspec->np)
+			genpd = provider->xlate(genpdspec, provider->data);
+		if (!IS_ERR(genpd))
+			break;
+	}
+
+	mutex_unlock(&of_genpd_mutex);
+
+	return genpd;
+}
+
+/**
+ * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
+ * @dev: Device to attach.
+ *
+ * Parse device's OF node to find a PM domain specifier. If such is found,
+ * attaches the device to retrieved pm_domain ops.
+ *
+ * Both generic and legacy Samsung-specific DT bindings are supported to keep
+ * backwards compatibility with existing DTBs.
+ *
+ * Returns 0 on successfully attached PM domain or negative error code.
+ */
+int genpd_dev_pm_attach(struct device *dev)
+{
+	struct of_phandle_args pd_args;
+	struct generic_pm_domain *pd;
+	int ret;
+
+	if (!dev->of_node)
+		return -ENODEV;
+
+	if (dev->pm_domain)
+		return -EEXIST;
+
+	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
+					"#power-domain-cells", 0, &pd_args);
+	if (ret < 0) {
+		if (ret != -ENOENT)
+			return ret;
+
+		/*
+		 * Try legacy Samsung-specific bindings
+		 * (for backwards compatibility of DT ABI)
+		 */
+		pd_args.args_count = 0;
+		pd_args.np = of_parse_phandle(dev->of_node,
+						"samsung,power-domain", 0);
+		if (!pd_args.np)
+			return -ENOENT;
+	}
+
+	pd = of_genpd_get_from_provider(&pd_args);
+	if (IS_ERR(pd)) {
+		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
+			__func__, PTR_ERR(pd));
+		of_node_put(dev->of_node);
+		return PTR_ERR(pd);
+	}
+
+	dev_dbg(dev, "adding to PM domain %s\n", pd->name);
+
+	while (1) {
+		ret = pm_genpd_add_device(pd, dev);
+		if (ret != -EAGAIN)
+			break;
+		cond_resched();
+	}
+
+	if (ret < 0) {
+		dev_err(dev, "failed to add to PM domain %s: %d",
+			pd->name, ret);
+		of_node_put(dev->of_node);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
+
+/**
+ * genpd_dev_pm_detach - Detach a device from its PM domain.
+ * @dev: Device to attach.
+ *
+ * Try to locate a corresponding generic PM domain, which the device was
+ * attached to previously. If such is found, the device is detached from it.
+ *
+ * Returns 0 on successfully detached PM domain or negative error code.
+ */
+int genpd_dev_pm_detach(struct device *dev)
+{
+	struct generic_pm_domain *pd = NULL, *gpd;
+	int ret = 0;
+
+	if (!dev->pm_domain)
+		return -ENODEV;
+
+	mutex_lock(&gpd_list_lock);
+	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
+		if (&gpd->domain == dev->pm_domain) {
+			pd = gpd;
+			break;
+		}
+	}
+	mutex_unlock(&gpd_list_lock);
+
+	if (!pd)
+		return -ENOENT;
+
+	dev_dbg(dev, "removing from PM domain %s\n", pd->name);
+
+	while (1) {
+		ret = pm_genpd_remove_device(pd, dev);
+		if (ret != -EAGAIN)
+			break;
+		cond_resched();
+	}
+
+	if (ret < 0) {
+		dev_err(dev, "failed to remove from PM domain %s: %d",
+			pd->name, ret);
+		return ret;
+	}
+
+	/* Check if PM domain can be powered off after removing this device. */
+	genpd_queue_power_off_work(pd);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(genpd_dev_pm_detach);
+#endif

@@ -310,4 +310,61 @@ static inline void pm_genpd_syscore_poweron(struct device *dev)
 	pm_genpd_syscore_switch(dev, false);
 }
 
+/* OF PM domain providers */
+struct of_device_id;
+
+struct genpd_onecell_data {
+	struct generic_pm_domain **domains;
+	unsigned int num_domains;
+};
+
+typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args,
+						void *data);
+
+#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
+int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
+			void *data);
+void of_genpd_del_provider(struct device_node *np);
+
+struct generic_pm_domain *__of_genpd_xlate_simple(
+					struct of_phandle_args *genpdspec,
+					void *data);
+struct generic_pm_domain *__of_genpd_xlate_onecell(
+					struct of_phandle_args *genpdspec,
+					void *data);
+
+int genpd_dev_pm_attach(struct device *dev);
+int genpd_dev_pm_detach(struct device *dev);
+#else /* !CONFIG_PM_GENERIC_DOMAINS_OF */
+static inline int __of_genpd_add_provider(struct device_node *np,
+					genpd_xlate_t xlate, void *data)
+{
+	return 0;
+}
+static inline void of_genpd_del_provider(struct device_node *np) {}
+
+#define __of_genpd_xlate_simple		NULL
+#define __of_genpd_xlate_onecell	NULL
+
+static inline int genpd_dev_pm_attach(struct device *dev)
+{
+	return -ENODEV;
+}
+static inline int genpd_dev_pm_detach(struct device *dev)
+{
+	return -ENODEV;
+}
+#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
+
+static inline int of_genpd_add_provider_simple(struct device_node *np,
+					struct generic_pm_domain *genpd)
+{
+	return __of_genpd_add_provider(np, __of_genpd_xlate_simple, genpd);
+}
+static inline int of_genpd_add_provider_onecell(struct device_node *np,
+					struct genpd_onecell_data *data)
+{
+	return __of_genpd_add_provider(np, __of_genpd_xlate_onecell, data);
+}
+
 #endif /* _LINUX_PM_DOMAIN_H */

@@ -302,6 +302,10 @@ config PM_GENERIC_DOMAINS_RUNTIME
 	def_bool y
 	depends on PM_RUNTIME && PM_GENERIC_DOMAINS
 
+config PM_GENERIC_DOMAINS_OF
+	def_bool y
+	depends on PM_GENERIC_DOMAINS && OF && !ARCH_EXYNOS
+
 config CPU_PM
 	bool
 	depends on SUSPEND || CPU_IDLE

@@ -11,6 +11,8 @@
 #include <linux/export.h>
 #include <linux/slab.h>
 #include <linux/pm_clock.h>
+#include <linux/acpi.h>
+#include <linux/pm_domain.h>
 
 /**
  * dev_pm_get_subsys_data - Create or refcount power.subsys_data for device.

@@ -82,3 +84,57 @@ int dev_pm_put_subsys_data(struct device *dev)
 	return ret;
 }
 EXPORT_SYMBOL_GPL(dev_pm_put_subsys_data);
+
+/**
+ * dev_pm_domain_attach - Attach a device to its PM domain.
+ * @dev: Device to attach.
+ * @power_on: Used to indicate whether we should power on the device.
+ *
+ * The @dev may only be attached to a single PM domain. By iterating through
+ * the available alternatives we try to find a valid PM domain for the device.
+ *
+ * This function should typically be invoked from subsystem level code during
+ * the probe phase. Especially for those that holds devices which requires
+ * power management through PM domains.
+ *
+ * Callers must ensure proper synchronization of this function with power
+ * management callbacks.
+ *
+ * Returns 0 on successfully attached PM domain or negative error code.
+ */
+int dev_pm_domain_attach(struct device *dev, bool power_on)
+{
+	int ret;
+
+	ret = acpi_dev_pm_attach(dev, power_on);
+	if (!ret || ret == -EPROBE_DEFER)
+		return ret;
+
+	return genpd_dev_pm_attach(dev);
+}
+EXPORT_SYMBOL_GPL(dev_pm_domain_attach);
+
+/**
+ * dev_pm_domain_detach - Detach a device from its PM domain.
+ * @dev: Device to attach.
+ * @power_off: Used to indicate whether we should power off the device.
+ *
+ * The @dev may be attached to a PM domain. By iterating through the available
+ * alternatives we detach it from its PM domain.
+ *
+ * This functions will reverse the actions from dev_pm_domain_attach() and thus
+ * detach the @dev from its PM domain. Typically it should be invoked from
+ * subsystem level code during the remove phase.
+ *
+ * Callers must ensure proper synchronization of this function with power
+ * management callbacks.
+ *
+ * Returns 0 on successfully detached PM domain or negative error code.
+ */
+int dev_pm_domain_detach(struct device *dev, bool power_off)
+{
+	if (acpi_dev_pm_detach(dev, power_off))
+		return genpd_dev_pm_detach(dev);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dev_pm_domain_detach);

@@ -621,6 +621,20 @@ struct dev_pm_domain {
 	struct dev_pm_ops	ops;
 };
 
+#ifdef CONFIG_PM
+extern int dev_pm_domain_attach(struct device *dev, bool power_on);
+extern int dev_pm_domain_detach(struct device *dev, bool power_off);
+#else
+static inline int dev_pm_domain_attach(struct device *dev, bool power_on)
+{
+	return -ENODEV;
+}
+static inline int dev_pm_domain_detach(struct device *dev, bool power_off)
+{
+	return -ENODEV;
+}
+#endif
+
 /*
  * The PM_EVENT_ messages are also used by drivers implementing the legacy
  * suspend framework, based on the ->suspend() and ->resume() callbacks common

@@ -506,11 +506,12 @@ static int platform_drv_probe(struct device *_dev)
 	if (ret < 0)
 		return ret;
 
-	acpi_dev_pm_attach(_dev, true);
-
-	ret = drv->probe(dev);
-	if (ret)
-		acpi_dev_pm_detach(_dev, true);
+	ret = dev_pm_domain_attach(_dev, true);
+	if (ret != -EPROBE_DEFER) {
+		ret = drv->probe(dev);
+		if (ret)
+			dev_pm_domain_detach(_dev, true);
+	}
 
 	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 		dev_warn(_dev, "probe deferral not supported\n");

@@ -532,7 +533,7 @@ static int platform_drv_remove(struct device *_dev)
 	int ret;
 
 	ret = drv->remove(dev);
-	acpi_dev_pm_detach(_dev, true);
+	dev_pm_domain_detach(_dev, true);
 
 	return ret;
 }

@@ -543,7 +544,7 @@ static void platform_drv_shutdown(struct device *_dev)
 	struct platform_device *dev = to_platform_device(_dev);
 
 	drv->shutdown(dev);
-	acpi_dev_pm_detach(_dev, true);
+	dev_pm_domain_detach(_dev, true);
 }
 
 /**

@@ -279,10 +279,13 @@ static int i2c_device_probe(struct device *dev)
 	if (status < 0)
 		return status;
 
-	acpi_dev_pm_attach(&client->dev, true);
-	status = driver->probe(client, i2c_match_id(driver->id_table, client));
-	if (status)
-		acpi_dev_pm_detach(&client->dev, true);
+	status = dev_pm_domain_attach(&client->dev, true);
+	if (status != -EPROBE_DEFER) {
+		status = driver->probe(client, i2c_match_id(driver->id_table,
+					client));
+		if (status)
+			dev_pm_domain_detach(&client->dev, true);
+	}
 
 	return status;
 }

@@ -302,7 +305,7 @@ static int i2c_device_remove(struct device *dev)
 		status = driver->remove(client);
 	}
 
-	acpi_dev_pm_detach(&client->dev, true);
+	dev_pm_domain_detach(&client->dev, true);
 	return status;
 }
 

@@ -315,7 +315,7 @@ int sdio_add_func(struct sdio_func *func)
 	ret = device_add(&func->dev);
 	if (ret == 0) {
 		sdio_func_set_present(func);
-		acpi_dev_pm_attach(&func->dev, false);
+		dev_pm_domain_attach(&func->dev, false);
 	}
 
 	return ret;

@@ -332,7 +332,7 @@ void sdio_remove_func(struct sdio_func *func)
 	if (!sdio_func_present(func))
 		return;
 
-	acpi_dev_pm_detach(&func->dev, false);
+	dev_pm_domain_detach(&func->dev, false);
 	device_del(&func->dev);
 	put_device(&func->dev);
 }

@@ -264,10 +264,12 @@ static int spi_drv_probe(struct device *dev)
 	if (ret)
 		return ret;
 
-	acpi_dev_pm_attach(dev, true);
-	ret = sdrv->probe(to_spi_device(dev));
-	if (ret)
-		acpi_dev_pm_detach(dev, true);
+	ret = dev_pm_domain_attach(dev, true);
+	if (ret != -EPROBE_DEFER) {
+		ret = sdrv->probe(to_spi_device(dev));
+		if (ret)
+			dev_pm_domain_detach(dev, true);
+	}
 
 	return ret;
 }

@@ -278,7 +280,7 @@ static int spi_drv_remove(struct device *dev)
 	int ret;
 
 	ret = sdrv->remove(to_spi_device(dev));
-	acpi_dev_pm_detach(dev, true);
+	dev_pm_domain_detach(dev, true);
 
 	return ret;
 }

@@ -182,9 +182,15 @@ static int amba_probe(struct device *dev)
 	int ret;
 
 	do {
+		ret = dev_pm_domain_attach(dev, true);
+		if (ret == -EPROBE_DEFER)
+			break;
+
 		ret = amba_get_enable_pclk(pcdev);
-		if (ret)
+		if (ret) {
+			dev_pm_domain_detach(dev, true);
 			break;
+		}
 
 		pm_runtime_get_noresume(dev);
 		pm_runtime_set_active(dev);

@@ -199,6 +205,7 @@ static int amba_probe(struct device *dev)
 		pm_runtime_put_noidle(dev);
 
 		amba_put_disable_pclk(pcdev);
+		dev_pm_domain_detach(dev, true);
 	} while (0);
 
 	return ret;

@@ -220,6 +227,7 @@ static int amba_remove(struct device *dev)
 	pm_runtime_put_noidle(dev);
 
 	amba_put_disable_pclk(pcdev);
+	dev_pm_domain_detach(dev, true);
 
 	return ret;
 }

@@ -8,6 +8,8 @@ Required Properties:
     * samsung,exynos4210-pd - for exynos4210 type power domain.
 - reg: physical base address of the controller and length of memory mapped
     region.
+- #power-domain-cells: number of cells in power domain specifier;
+    must be 0.
 
 Optional Properties:
 - clocks: List of clock handles. The parent clocks of the input clocks to the

@@ -29,6 +31,7 @@ Example:
 	lcd0: power-domain-lcd0 {
 		compatible = "samsung,exynos4210-pd";
 		reg = <0x10023C00 0x10>;
+		#power-domain-cells = <0>;
 	};
 
 	mfc_pd: power-domain at 10044060 {

@@ -37,12 +40,8 @@ Example:
 		clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_SW_ACLK333>,
 			<&clock CLK_MOUT_USER_ACLK333>;
 		clock-names = "oscclk", "pclk0", "clk0";
+		#power-domain-cells = <0>;
 	};
 
-Example of the node using power domain:
-
-	node {
-		/* ... */
-		samsung,power-domain = <&lcd0>;
-		/* ... */
-	};
+See Documentation/devicetree/bindings/power/power_domain.txt for description
+of consumer-side bindings.

@@ -105,78 +105,6 @@ static int exynos_pd_power_off(struct generic_pm_domain *domain)
 	return exynos_pd_power(domain, false);
 }
 
-static void exynos_add_device_to_domain(struct exynos_pm_domain *pd,
-					 struct device *dev)
-{
-	int ret;
-
-	dev_dbg(dev, "adding to power domain %s\n", pd->pd.name);
-
-	while (1) {
-		ret = pm_genpd_add_device(&pd->pd, dev);
-		if (ret != -EAGAIN)
-			break;
-		cond_resched();
-	}
-
-	pm_genpd_dev_need_restore(dev, true);
-}
-
-static void exynos_remove_device_from_domain(struct device *dev)
-{
-	struct generic_pm_domain *genpd = dev_to_genpd(dev);
-	int ret;
-
-	dev_dbg(dev, "removing from power domain %s\n", genpd->name);
-
-	while (1) {
-		ret = pm_genpd_remove_device(genpd, dev);
-		if (ret != -EAGAIN)
-			break;
-		cond_resched();
-	}
-}
-
-static void exynos_read_domain_from_dt(struct device *dev)
-{
-	struct platform_device *pd_pdev;
-	struct exynos_pm_domain *pd;
-	struct device_node *node;
-
-	node = of_parse_phandle(dev->of_node, "samsung,power-domain", 0);
-	if (!node)
-		return;
-	pd_pdev = of_find_device_by_node(node);
-	if (!pd_pdev)
-		return;
-	pd = platform_get_drvdata(pd_pdev);
-	exynos_add_device_to_domain(pd, dev);
-}
-
-static int exynos_pm_notifier_call(struct notifier_block *nb,
-				    unsigned long event, void *data)
-{
-	struct device *dev = data;
-
-	switch (event) {
-	case BUS_NOTIFY_BIND_DRIVER:
-		if (dev->of_node)
-			exynos_read_domain_from_dt(dev);
-
-		break;
-
-	case BUS_NOTIFY_UNBOUND_DRIVER:
-		exynos_remove_device_from_domain(dev);
-
-		break;
-	}
-	return NOTIFY_DONE;
-}
-
-static struct notifier_block platform_nb = {
-	.notifier_call = exynos_pm_notifier_call,
-};
-
 static __init int exynos4_pm_init_power_domain(void)
 {
 	struct platform_device *pdev;

@@ -202,7 +130,6 @@ static __init int exynos4_pm_init_power_domain(void)
 		pd->base = of_iomap(np, 0);
 		pd->pd.power_off = exynos_pd_power_off;
 		pd->pd.power_on = exynos_pd_power_on;
-		pd->pd.of_node = np;
 
 		pd->oscclk = clk_get(dev, "oscclk");
 		if (IS_ERR(pd->oscclk))

@@ -228,15 +155,12 @@ static __init int exynos4_pm_init_power_domain(void)
 			clk_put(pd->oscclk);
 
 no_clk:
-		platform_set_drvdata(pdev, pd);
-
 		on = __raw_readl(pd->base + 0x4) & INT_LOCAL_PWR_EN;
 
 		pm_genpd_init(&pd->pd, NULL, !on);
+		of_genpd_add_provider_simple(np, &pd->pd);
 	}
 
-	bus_register_notifier(&platform_bus_type, &platform_nb);
-
 	return 0;
 }
 arch_initcall(exynos4_pm_init_power_domain);

@@ -304,7 +304,7 @@ config PM_GENERIC_DOMAINS_RUNTIME
 
 config PM_GENERIC_DOMAINS_OF
 	def_bool y
-	depends on PM_GENERIC_DOMAINS && OF && !ARCH_EXYNOS
+	depends on PM_GENERIC_DOMAINS && OF
 
 config CPU_PM
 	bool