PM / Domains: add setter for dev.pm_domain

Adds a function that sets the pointer to dev_pm_domain in struct device
and that warns if the device has already finished probing. The reason
why we want to enforce that is because in the general case that can
cause problems and also that we can simplify code quite a bit if we can
always assume that.

This patch also changes all current code that directly sets the
dev.pm_domain pointer.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/arm/mach-omap2/omap_device.c

@@ -32,6 +32,7 @@
 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/clkdev.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/of.h>
 #include <linux/notifier.h>
@@ -168,7 +169,7 @@ static int omap_device_build_from_dt(struct platform_device *pdev)
 			r->name = dev_name(&pdev->dev);
 	}
 
-	pdev->dev.pm_domain = &omap_device_pm_domain;
+	dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
 
 	if (device_active) {
 		omap_device_enable(pdev);
@@ -180,7 +181,7 @@ odbfd_exit1:
 odbfd_exit:
 	/* if data/we are at fault.. load up a fail handler */
 	if (ret)
-		pdev->dev.pm_domain = &omap_device_fail_pm_domain;
+		dev_pm_domain_set(&pdev->dev, &omap_device_fail_pm_domain);
 
 	return ret;
 }
@@ -701,7 +702,7 @@ int omap_device_register(struct platform_device *pdev)
 {
 	pr_debug("omap_device: %s: registering\n", pdev->name);
 
-	pdev->dev.pm_domain = &omap_device_pm_domain;
+	dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
 	return platform_device_add(pdev);
 }
 

drivers/acpi/acpi_lpss.c

@@ -18,6 +18,7 @@
 #include <linux/mutex.h>
 #include <linux/platform_device.h>
 #include <linux/platform_data/clk-lpss.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/delay.h>
 
@@ -875,13 +876,14 @@ static int acpi_lpss_platform_notify(struct notifier_block *nb,
 
 	switch (action) {
 	case BUS_NOTIFY_BIND_DRIVER:
-		pdev->dev.pm_domain = &acpi_lpss_pm_domain;
+		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
 		break;
 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
 	case BUS_NOTIFY_UNBOUND_DRIVER:
 		pdev->dev.pm_domain = NULL;
 		break;
 	case BUS_NOTIFY_ADD_DEVICE:
+		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
 		if (pdata->dev_desc->flags & LPSS_LTR)
 			return sysfs_create_group(&pdev->dev.kobj,
 						  &lpss_attr_group);
@@ -889,6 +891,7 @@ static int acpi_lpss_platform_notify(struct notifier_block *nb,
 	case BUS_NOTIFY_DEL_DEVICE:
 		if (pdata->dev_desc->flags & LPSS_LTR)
 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
+		dev_pm_domain_set(&pdev->dev, NULL);
 		break;
 	default:
 		break;

drivers/acpi/device_pm.c

@@ -22,6 +22,7 @@
 #include <linux/export.h>
 #include <linux/mutex.h>
 #include <linux/pm_qos.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 
 #include "internal.h"
@@ -1059,7 +1060,7 @@ static void acpi_dev_pm_detach(struct device *dev, bool power_off)
 	struct acpi_device *adev = ACPI_COMPANION(dev);
 
 	if (adev && dev->pm_domain == &acpi_general_pm_domain) {
-		dev->pm_domain = NULL;
+		dev_pm_domain_set(dev, NULL);
 		acpi_remove_pm_notifier(adev);
 		if (power_off) {
 			/*
@@ -1111,7 +1112,7 @@ int acpi_dev_pm_attach(struct device *dev, bool power_on)
 		return -EBUSY;
 
 	acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
-	dev->pm_domain = &acpi_general_pm_domain;
+	dev_pm_domain_set(dev, &acpi_general_pm_domain);
 	if (power_on) {
 		acpi_dev_pm_full_power(adev);
 		acpi_device_wakeup(adev, ACPI_STATE_S0, false);

drivers/base/power/clock_ops.c

@@ -15,6 +15,7 @@
 #include <linux/clkdev.h>
 #include <linux/slab.h>
 #include <linux/err.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 
 #ifdef CONFIG_PM_CLK
@@ -348,7 +349,7 @@ static int pm_clk_notify(struct notifier_block *nb,
 		if (error)
 			break;
 
-		dev->pm_domain = clknb->pm_domain;
+		dev_pm_domain_set(dev, clknb->pm_domain);
 		if (clknb->con_ids[0]) {
 			for (con_id = clknb->con_ids; *con_id; con_id++)
 				pm_clk_add(dev, *con_id);
@@ -361,7 +362,7 @@ static int pm_clk_notify(struct notifier_block *nb,
 		if (dev->pm_domain != clknb->pm_domain)
 			break;
 
-		dev->pm_domain = NULL;
+		dev_pm_domain_set(dev, NULL);
 		pm_clk_destroy(dev);
 		break;
 	}

drivers/base/power/common.c

@@ -128,3 +128,24 @@ void dev_pm_domain_detach(struct device *dev, bool power_off)
 		dev->pm_domain->detach(dev, power_off);
 }
 EXPORT_SYMBOL_GPL(dev_pm_domain_detach);
+
+/**
+ * dev_pm_domain_set - Set PM domain of a device.
+ * @dev: Device whose PM domain is to be set.
+ * @pd: PM domain to be set, or NULL.
+ *
+ * Sets the PM domain the device belongs to. The PM domain of a device needs
+ * to be set before its probe finishes (it's bound to a driver).
+ *
+ * This function must be called with the device lock held.
+ */
+void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd)
+{
+	if (dev->pm_domain == pd)
+		return;
+
+	WARN(device_is_bound(dev),
+	     "PM domains can only be changed for unbound devices\n");
+	dev->pm_domain = pd;
+}
+EXPORT_SYMBOL_GPL(dev_pm_domain_set);

drivers/base/power/domain.c

@@ -1177,10 +1177,11 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
 	}
 
 	dev->power.subsys_data->domain_data = &gpd_data->base;
-	dev->pm_domain = &genpd->domain;
 
 	spin_unlock_irq(&dev->power.lock);
 
+	dev_pm_domain_set(dev, &genpd->domain);
+
 	return gpd_data;
 
  err_free:
@@ -1194,9 +1195,10 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
 static void genpd_free_dev_data(struct device *dev,
 				struct generic_pm_domain_data *gpd_data)
 {
+	dev_pm_domain_set(dev, NULL);
+
 	spin_lock_irq(&dev->power.lock);
 
-	dev->pm_domain = NULL;
 	dev->power.subsys_data->domain_data = NULL;
 
 	spin_unlock_irq(&dev->power.lock);

drivers/gpu/vga/vga_switcheroo.c

@@ -36,6 +36,7 @@
 #include <linux/fs.h>
 #include <linux/module.h>
 #include <linux/pci.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/seq_file.h>
 #include <linux/uaccess.h>
@@ -918,17 +919,17 @@ int vga_switcheroo_init_domain_pm_ops(struct device *dev,
 		domain->ops.runtime_suspend = vga_switcheroo_runtime_suspend;
 		domain->ops.runtime_resume = vga_switcheroo_runtime_resume;
 
-		dev->pm_domain = domain;
+		dev_pm_domain_set(dev, domain);
 		return 0;
 	}
-	dev->pm_domain = NULL;
+	dev_pm_domain_set(dev, NULL);
 	return -EINVAL;
 }
 EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_ops);
 
 void vga_switcheroo_fini_domain_pm_ops(struct device *dev)
 {
-	dev->pm_domain = NULL;
+	dev_pm_domain_set(dev, NULL);
 }
 EXPORT_SYMBOL(vga_switcheroo_fini_domain_pm_ops);
 
@@ -989,10 +990,10 @@ vga_switcheroo_init_domain_pm_optimus_hdmi_audio(struct device *dev,
 		domain->ops.runtime_resume =
 			vga_switcheroo_runtime_resume_hdmi_audio;
 
-		dev->pm_domain = domain;
+		dev_pm_domain_set(dev, domain);
 		return 0;
 	}
-	dev->pm_domain = NULL;
+	dev_pm_domain_set(dev, NULL);
 	return -EINVAL;
 }
 EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_optimus_hdmi_audio);

drivers/misc/mei/pci-me.c

@@ -31,6 +31,7 @@
 #include <linux/jiffies.h>
 #include <linux/interrupt.h>
 
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 
 #include <linux/mei.h>
@@ -436,7 +437,7 @@ static inline void mei_me_set_pm_domain(struct mei_device *dev)
 		dev->pg_domain.ops.runtime_resume = mei_me_pm_runtime_resume;
 		dev->pg_domain.ops.runtime_idle = mei_me_pm_runtime_idle;
 
-		pdev->dev.pm_domain = &dev->pg_domain;
+		dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
 	}
 }
 
@@ -448,7 +449,7 @@ static inline void mei_me_set_pm_domain(struct mei_device *dev)
 static inline void mei_me_unset_pm_domain(struct mei_device *dev)
 {
 	/* stop using pm callbacks if any */
-	dev->dev->pm_domain = NULL;
+	dev_pm_domain_set(dev->dev, NULL);
 }
 
 static const struct dev_pm_ops mei_me_pm_ops = {

drivers/misc/mei/pci-txe.c

@@ -27,6 +27,7 @@
 #include <linux/jiffies.h>
 #include <linux/interrupt.h>
 #include <linux/workqueue.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 
 #include <linux/mei.h>
@@ -388,7 +389,7 @@ static inline void mei_txe_set_pm_domain(struct mei_device *dev)
 		dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
 		dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
 
-		pdev->dev.pm_domain = &dev->pg_domain;
+		dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
 	}
 }
 
@@ -400,7 +401,7 @@ static inline void mei_txe_set_pm_domain(struct mei_device *dev)
 static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
 {
 	/* stop using pm callbacks if any */
-	dev->dev->pm_domain = NULL;
+	dev_pm_domain_set(dev->dev, NULL);
 }
 
 static const struct dev_pm_ops mei_txe_pm_ops = {

include/linux/pm_domain.h

@@ -240,12 +240,15 @@ static inline int of_genpd_add_provider_onecell(struct device_node *np,
 #ifdef CONFIG_PM
 extern int dev_pm_domain_attach(struct device *dev, bool power_on);
 extern void dev_pm_domain_detach(struct device *dev, bool power_off);
+extern void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd);
 #else
 static inline int dev_pm_domain_attach(struct device *dev, bool power_on)
 {
 	return -ENODEV;
 }
 static inline void dev_pm_domain_detach(struct device *dev, bool power_off) {}
+static inline void dev_pm_domain_set(struct device *dev,
+				     struct dev_pm_domain *pd) {}
 #endif
 
 #endif /* _LINUX_PM_DOMAIN_H */