ACPI: platform_profile: Remove platform_profile_handler from exported symbols

In order to protect the platform_profile_handler from API consumers,
allocate it in platform_profile_register() and modify it's signature
accordingly.

Remove the platform_profile_handler from all consumer drivers and
replace them with a pointer to the class device, which is
now returned from platform_profile_register().

Replace *pprof with a pointer to the class device in the rest of
exported symbols.

Reviewed-by: Mario Limonciello <[email protected]>
Signed-off-by: Kurt Borja <[email protected]>
Reviewed-by: Mark Pearson <[email protected]>
Tested-by: Mark Pearson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Ilpo Järvinen <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>

Author: kuu-rt

drivers/acpi/platform_profile.c

@@ -4,6 +4,7 @@
 
 #include <linux/acpi.h>
 #include <linux/bits.h>
+#include <linux/cleanup.h>
 #include <linux/init.h>
 #include <linux/mutex.h>
 #include <linux/platform_profile.h>
@@ -212,9 +213,17 @@ static struct attribute *profile_attrs[] = {
 };
 ATTRIBUTE_GROUPS(profile);
 
+static void pprof_device_release(struct device *dev)
+{
+	struct platform_profile_handler *pprof = to_pprof_handler(dev);
+
+	kfree(pprof);
+}
+
 static const struct class platform_profile_class = {
 	.name = "platform-profile",
 	.dev_groups = profile_groups,
+	.dev_release = pprof_device_release,
 };
 
 /**
@@ -408,10 +417,10 @@ static const struct attribute_group platform_profile_group = {
 	.is_visible = profile_class_is_visible,
 };
 
-void platform_profile_notify(struct platform_profile_handler *pprof)
+void platform_profile_notify(struct device *dev)
 {
 	scoped_cond_guard(mutex_intr, return, &profile_lock) {
-		_notify_class_profile(&pprof->class_dev, NULL);
+		_notify_class_profile(dev, NULL);
 	}
 	sysfs_notify(acpi_kobj, NULL, "platform_profile");
 }
@@ -460,42 +469,54 @@ int platform_profile_cycle(void)
 }
 EXPORT_SYMBOL_GPL(platform_profile_cycle);
 
-int platform_profile_register(struct platform_profile_handler *pprof, void *drvdata)
+struct device *platform_profile_register(struct device *dev, const char *name,
+					 void *drvdata,
+					 const struct platform_profile_ops *ops)
 {
+	struct device *ppdev;
+	int minor;
 	int err;
 
-	/* Sanity check the profile handler */
-	if (!pprof || !pprof->ops->profile_set || !pprof->ops->profile_get ||
-	    !pprof->ops->probe) {
-		pr_err("platform_profile: handler is invalid\n");
-		return -EINVAL;
-	}
+	/* Sanity check */
+	if (WARN_ON_ONCE(!dev || !name || !ops || !ops->profile_get ||
+	    !ops->profile_set || !ops->probe))
+		return ERR_PTR(-EINVAL);
+
+	struct platform_profile_handler *pprof __free(kfree) = kzalloc(
+		sizeof(*pprof), GFP_KERNEL);
+	if (!pprof)
+		return ERR_PTR(-ENOMEM);
 
-	err = pprof->ops->probe(drvdata, pprof->choices);
+	err = ops->probe(drvdata, pprof->choices);
 	if (err) {
-		dev_err(pprof->dev, "platform_profile probe failed\n");
-		return err;
+		dev_err(dev, "platform_profile probe failed\n");
+		return ERR_PTR(err);
 	}
 
 	if (bitmap_empty(pprof->choices, PLATFORM_PROFILE_LAST)) {
-		dev_err(pprof->dev, "Failed to register a platform_profile class device with empty choices\n");
-		return -EINVAL;
+		dev_err(dev, "Failed to register platform_profile class device with empty choices\n");
+		return ERR_PTR(-EINVAL);
 	}
 
 	guard(mutex)(&profile_lock);
 
 	/* create class interface for individual handler */
-	pprof->minor = ida_alloc(&platform_profile_ida, GFP_KERNEL);
-	if (pprof->minor < 0)
-		return pprof->minor;
+	minor = ida_alloc(&platform_profile_ida, GFP_KERNEL);
+	if (minor < 0)
+		return ERR_PTR(minor);
 
+	pprof->name = name;
+	pprof->ops = ops;
+	pprof->minor = minor;
 	pprof->class_dev.class = &platform_profile_class;
-	pprof->class_dev.parent = pprof->dev;
+	pprof->class_dev.parent = dev;
 	dev_set_drvdata(&pprof->class_dev, drvdata);
 	dev_set_name(&pprof->class_dev, "platform-profile-%d", pprof->minor);
-	err = device_register(&pprof->class_dev);
+	/* device_register() takes ownership of pprof/ppdev */
+	ppdev = &no_free_ptr(pprof)->class_dev;
+	err = device_register(ppdev);
 	if (err) {
-		put_device(&pprof->class_dev);
+		put_device(ppdev);
 		goto cleanup_ida;
 	}
 
@@ -505,20 +526,21 @@ int platform_profile_register(struct platform_profile_handler *pprof, void *drvd
 	if (err)
 		goto cleanup_cur;
 
-	return 0;
+	return ppdev;
 
 cleanup_cur:
-	device_unregister(&pprof->class_dev);
+	device_unregister(ppdev);
 
 cleanup_ida:
-	ida_free(&platform_profile_ida, pprof->minor);
+	ida_free(&platform_profile_ida, minor);
 
-	return err;
+	return ERR_PTR(err);
 }
 EXPORT_SYMBOL_GPL(platform_profile_register);
 
-int platform_profile_remove(struct platform_profile_handler *pprof)
+int platform_profile_remove(struct device *dev)
 {
+	struct platform_profile_handler *pprof = to_pprof_handler(dev);
 	int id;
 	guard(mutex)(&profile_lock);
 
@@ -536,30 +558,32 @@ EXPORT_SYMBOL_GPL(platform_profile_remove);
 
 static void devm_platform_profile_release(struct device *dev, void *res)
 {
-	struct platform_profile_handler **pprof = res;
+	struct device **ppdev = res;
 
-	platform_profile_remove(*pprof);
+	platform_profile_remove(*ppdev);
 }
 
-int devm_platform_profile_register(struct platform_profile_handler *pprof, void *drvdata)
+struct device *devm_platform_profile_register(struct device *dev, const char *name,
+					      void *drvdata,
+					      const struct platform_profile_ops *ops)
 {
-	struct platform_profile_handler **dr;
-	int ret;
+	struct device *ppdev;
+	struct device **dr;
 
 	dr = devres_alloc(devm_platform_profile_release, sizeof(*dr), GFP_KERNEL);
 	if (!dr)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
-	ret = platform_profile_register(pprof, drvdata);
-	if (ret) {
+	ppdev = platform_profile_register(dev, name, drvdata, ops);
+	if (IS_ERR(ppdev)) {
 		devres_free(dr);
-		return ret;
+		return ppdev;
 	}
 
-	*dr = pprof;
-	devres_add(pprof->dev, dr);
+	*dr = ppdev;
+	devres_add(dev, dr);
 
-	return 0;
+	return ppdev;
 }
 EXPORT_SYMBOL_GPL(devm_platform_profile_register);
 

drivers/platform/surface/surface_platform_profile.c

@@ -40,7 +40,7 @@ struct ssam_tmp_profile_info {
 
 struct ssam_platform_profile_device {
 	struct ssam_device *sdev;
-	struct platform_profile_handler handler;
+	struct device *ppdev;
 	bool has_fan;
 };
 
@@ -228,13 +228,12 @@ static int surface_platform_profile_probe(struct ssam_device *sdev)
 	tpd->sdev = sdev;
 	ssam_device_set_drvdata(sdev, tpd);
 
-	tpd->handler.name = "Surface Platform Profile";
-	tpd->handler.dev = &sdev->dev;
-	tpd->handler.ops = &ssam_platform_profile_ops;
-
 	tpd->has_fan = device_property_read_bool(&sdev->dev, "has_fan");
 
-	return devm_platform_profile_register(&tpd->handler, tpd);
+	tpd->ppdev = devm_platform_profile_register(&sdev->dev, "Surface Platform Profile",
+						    tpd, &ssam_platform_profile_ops);
+
+	return PTR_ERR_OR_ZERO(tpd->ppdev);
 }
 
 static const struct ssam_device_id ssam_platform_profile_match[] = {

drivers/platform/x86/acer-wmi.c

@@ -784,7 +784,7 @@ static const struct dmi_system_id non_acer_quirks[] __initconst = {
 	{}
 };
 
-static struct platform_profile_handler platform_profile_handler;
+static struct device *platform_profile_device;
 static bool platform_profile_support;
 
 /*
@@ -2073,16 +2073,10 @@ static const struct platform_profile_ops acer_predator_v4_platform_profile_ops =
 static int acer_platform_profile_setup(struct platform_device *device)
 {
 	if (quirks->predator_v4) {
-		int err;
-
-		platform_profile_handler.name = "acer-wmi";
-		platform_profile_handler.dev = &device->dev;
-		platform_profile_handler.ops =
-			&acer_predator_v4_platform_profile_ops;
-
-		err = devm_platform_profile_register(&platform_profile_handler, NULL);
-		if (err)
-			return err;
+		platform_profile_device = devm_platform_profile_register(
+			&device->dev, "acer-wmi", NULL, &acer_predator_v4_platform_profile_ops);
+		if (IS_ERR(platform_profile_device))
+			return PTR_ERR(platform_profile_device);
 
 		platform_profile_support = true;
 
@@ -2125,7 +2119,7 @@ static int acer_thermal_profile_change(void)
 			if (current_tp != acer_predator_v4_max_perf)
 				last_non_turbo_profile = current_tp;
 
-			platform_profile_notify(&platform_profile_handler);
+			platform_profile_notify(platform_profile_device);
 		}
 	}
 

drivers/platform/x86/amd/pmf/pmf.h

@@ -338,7 +338,7 @@ struct amd_pmf_dev {
 	struct mutex lock; /* protects the PMF interface */
 	u32 supported_func;
 	enum platform_profile_option current_profile;
-	struct platform_profile_handler pprof;
+	struct device *ppdev; /* platform profile class device */
 	struct dentry *dbgfs_dir;
 	int hb_interval; /* SBIOS heartbeat interval */
 	struct delayed_work heart_beat;

drivers/platform/x86/amd/pmf/sps.c

@@ -404,8 +404,6 @@ static const struct platform_profile_ops amd_pmf_profile_ops = {
 
 int amd_pmf_init_sps(struct amd_pmf_dev *dev)
 {
-	int err;
-
 	dev->current_profile = PLATFORM_PROFILE_BALANCED;
 
 	if (is_apmf_func_supported(dev, APMF_FUNC_STATIC_SLIDER_GRANULAR)) {
@@ -420,15 +418,12 @@ int amd_pmf_init_sps(struct amd_pmf_dev *dev)
 		amd_pmf_set_sps_power_limits(dev);
 	}
 
-	dev->pprof.name = "amd-pmf";
-	dev->pprof.dev = dev->dev;
-	dev->pprof.ops = &amd_pmf_profile_ops;
-
 	/* Create platform_profile structure and register */
-	err = devm_platform_profile_register(&dev->pprof, dev);
-	if (err)
-		dev_err(dev->dev, "Failed to register SPS support, this is most likely an SBIOS bug: %d\n",
-			err);
+	dev->ppdev = devm_platform_profile_register(dev->dev, "amd-pmf", dev,
+						    &amd_pmf_profile_ops);
+	if (IS_ERR(dev->ppdev))
+		dev_err(dev->dev, "Failed to register SPS support, this is most likely an SBIOS bug: %ld\n",
+			PTR_ERR(dev->ppdev));
 
-	return err;
+	return PTR_ERR_OR_ZERO(dev->ppdev);
 }

drivers/platform/x86/asus-wmi.c

@@ -313,7 +313,7 @@ struct asus_wmi {
 	bool mid_fan_curve_available;
 	struct fan_curve_data custom_fan_curves[3];
 
-	struct platform_profile_handler platform_profile_handler;
+	struct device *ppdev;
 	bool platform_profile_support;
 
 	// The RSOC controls the maximum charging percentage.
@@ -3789,7 +3789,7 @@ static ssize_t throttle_thermal_policy_store(struct device *dev,
 	 * Ensure that platform_profile updates userspace with the change to ensure
 	 * that platform_profile and throttle_thermal_policy_mode are in sync.
 	 */
-	platform_profile_notify(&asus->platform_profile_handler);
+	platform_profile_notify(asus->ppdev);
 
 	return count;
 }
@@ -3891,14 +3891,11 @@ static int platform_profile_setup(struct asus_wmi *asus)
 
 	dev_info(dev, "Using throttle_thermal_policy for platform_profile support\n");
 
-	asus->platform_profile_handler.name = "asus-wmi";
-	asus->platform_profile_handler.dev = dev;
-	asus->platform_profile_handler.ops = &asus_wmi_platform_profile_ops;
-
-	err = devm_platform_profile_register(&asus->platform_profile_handler, asus);
-	if (err) {
+	asus->ppdev = devm_platform_profile_register(dev, "asus-wmi", asus,
+						     &asus_wmi_platform_profile_ops);
+	if (IS_ERR(asus->ppdev)) {
 		dev_err(dev, "Failed to register a platform_profile class device\n");
-		return err;
+		return PTR_ERR(asus->ppdev);
 	}
 
 	asus->platform_profile_support = true;

drivers/platform/x86/dell/alienware-wmi.c

@@ -406,7 +406,6 @@ struct wmax_u32_args {
 
 static struct platform_device *platform_device;
 static struct color_platform colors[4];
-static struct platform_profile_handler pp_handler;
 static enum wmax_thermal_mode supported_thermal_profiles[PLATFORM_PROFILE_LAST];
 
 static u8 interface;
@@ -1135,11 +1134,12 @@ static const struct platform_profile_ops awcc_platform_profile_ops = {
 
 static int create_thermal_profile(struct platform_device *platform_device)
 {
-	pp_handler.name = "alienware-wmi";
-	pp_handler.dev = &platform_device->dev;
-	pp_handler.ops = &awcc_platform_profile_ops;
+	struct device *ppdev;
 
-	return devm_platform_profile_register(&pp_handler, NULL);
+	ppdev = devm_platform_profile_register(&platform_device->dev, "alienware-wmi",
+					       NULL, &awcc_platform_profile_ops);
+
+	return PTR_ERR_OR_ZERO(ppdev);
 }
 
 /*

drivers/platform/x86/dell/dell-pc.c

@@ -109,8 +109,6 @@ MODULE_DEVICE_TABLE(dmi, dell_device_table);
 #define DELL_ACC_SET_FIELD	GENMASK(11, 8)
 #define DELL_THERMAL_SUPPORTED	GENMASK(3, 0)
 
-static struct platform_profile_handler *thermal_handler;
-
 enum thermal_mode_bits {
 	DELL_BALANCED    = BIT(0),
 	DELL_COOL_BOTTOM = BIT(1),
@@ -254,6 +252,7 @@ static const struct platform_profile_ops dell_pc_platform_profile_ops = {
 
 static int thermal_init(void)
 {
+	struct device *ppdev;
 	int ret;
 
 	/* If thermal commands are not supported, exit without error */
@@ -271,25 +270,15 @@ static int thermal_init(void)
 	if (IS_ERR(platform_device))
 		return PTR_ERR(platform_device);
 
-	thermal_handler = devm_kzalloc(&platform_device->dev, sizeof(*thermal_handler), GFP_KERNEL);
-	if (!thermal_handler) {
-		ret = -ENOMEM;
+	ppdev = devm_platform_profile_register(&platform_device->dev, "dell-pc",
+					       NULL, &dell_pc_platform_profile_ops);
+	if (IS_ERR(ppdev)) {
+		ret = PTR_ERR(ppdev);
 		goto cleanup_platform_device;
 	}
-	thermal_handler->name = "dell-pc";
-	thermal_handler->dev = &platform_device->dev;
-	thermal_handler->ops = &dell_pc_platform_profile_ops;
-
-	/* Clean up if failed */
-	ret = devm_platform_profile_register(thermal_handler, NULL);
-	if (ret)
-		goto cleanup_thermal_handler;
 
 	return 0;
 
-cleanup_thermal_handler:
-	thermal_handler = NULL;
-
 cleanup_platform_device:
 	platform_device_unregister(platform_device);