[PATCH v1 3/4] platform profile: Add firmware-neutral aggregate sysfs interface

[Daniel Lezcano]

The per-provider class interface is firmware-independent, but system-
wide profile selection is only exposed under /sys/firmware/acpi.

Add /sys/kernel/platform_profile/{choices,profile}, sharing the existing
aggregate callbacks and semantics with the legacy interface. Keep
attributes hidden until a provider is registered and remove them after
the last provider.

Notify both aggregate frontends on profile changes. Also notify the
provider class device on a direct profile write, matching its documented
POLLPRI ABI. Restore aggregate visibility after a failed registration.

Assisted-by: OpenCode:gpt-6.1-sol
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxxxxxxxx>
---
 drivers/platform/profile/core.c | 60 +++++++++++++++++++++++++++++----
 1 file changed, 53 insertions(+), 7 deletions(-)

diff --git a/drivers/platform/profile/core.c b/drivers/platform/profile/core.c
index f18fd96b942c..507b96bdfdb1 100644
--- a/drivers/platform/profile/core.c
+++ b/drivers/platform/profile/core.c
@@ -26,9 +26,11 @@ static DEFINE_MUTEX(profile_lock);
 static DEFINE_MUTEX(profile_registration_lock);
 static LIST_HEAD(profile_handlers);
 static struct kobject *compat_kobj;
+static struct kobject *profile_kobj;
 
 static void profile_notify(void)
 {
+	sysfs_notify(profile_kobj, NULL, "profile");
 	if (compat_kobj)
 		sysfs_notify(compat_kobj, NULL, "platform_profile");
 }
@@ -250,6 +252,7 @@ static ssize_t profile_store(struct device *dev,
 		ret = _store_class_profile(dev, &index);
 		if (ret)
 			return ret;
+		_notify_class_profile(dev, NULL);
 	}
 
 	profile_notify();
@@ -324,7 +327,7 @@ static int _remove_hidden_choices(struct device *dev, void *arg)
 }
 
 /**
- * platform_profile_choices_show - Show the available profile choices for legacy sysfs interface
+ * platform_profile_choices_show - Show the aggregate profile choices
  * @kobj: The kobject
  * @attr: The attribute
  * @buf: The buffer to write to
@@ -360,7 +363,7 @@ static ssize_t platform_profile_choices_show(struct kobject *kobj,
 }
 
 /**
- * _aggregate_profiles - Aggregate the profiles for legacy sysfs interface
+ * _aggregate_profiles - Aggregate the profiles across providers
  * @dev: The device
  * @data: The profile to return
  *
@@ -385,7 +388,7 @@ static int _aggregate_profiles(struct device *dev, void *data)
 }
 
 /**
- * _store_and_notify - Store and notify a class from legacy sysfs interface
+ * _store_and_notify - Store and notify a provider from an aggregate write
  * @dev: The device
  * @data: The profile to return
  *
@@ -403,7 +406,7 @@ static int _store_and_notify(struct device *dev, void *data)
 }
 
 /**
- * platform_profile_show - Show the current profile for legacy sysfs interface
+ * platform_profile_show - Show the current aggregate profile
  * @kobj: The kobject
  * @attr: The attribute
  * @buf: The buffer to write to
@@ -431,7 +434,7 @@ static ssize_t platform_profile_show(struct kobject *kobj,
 }
 
 /**
- * platform_profile_store - Set the profile for legacy sysfs interface
+ * platform_profile_store - Set the profile across all providers
  * @kobj: The kobject
  * @attr: The attribute
  * @buf: The buffer to read from
@@ -493,8 +496,30 @@ static const struct attribute_group platform_profile_group = {
 	.is_visible = profile_class_is_visible,
 };
 
+static struct kobj_attribute aggregate_choices =
+	__ATTR(choices, 0444, platform_profile_choices_show, NULL);
+static struct kobj_attribute aggregate_profile =
+	__ATTR(profile, 0644, platform_profile_show, platform_profile_store);
+
+static struct attribute *aggregate_attrs[] = {
+	&aggregate_choices.attr,
+	&aggregate_profile.attr,
+	NULL
+};
+
+static const struct attribute_group aggregate_group = {
+	.attrs = aggregate_attrs,
+	.is_visible = profile_class_is_visible,
+};
+
 static int profile_update(void)
 {
+	int err;
+
+	err = sysfs_update_group(profile_kobj, &aggregate_group);
+	if (err)
+		return err;
+
 	if (compat_kobj)
 		return sysfs_update_group(compat_kobj, &platform_profile_group);
 
@@ -502,7 +527,7 @@ static int profile_update(void)
 }
 
 /**
- * platform_profile_notify - Notify class device and legacy sysfs interface
+ * platform_profile_notify - Notify the provider and aggregate sysfs interfaces
  * @dev: The class device
  */
 void platform_profile_notify(struct device *dev)
@@ -643,6 +668,7 @@ struct device *platform_profile_register(struct device *dev, const char *name,
 cleanup_cur:
 	scoped_guard(mutex, &profile_lock)
 		list_del(&to_pprof_handler(ppdev)->node);
+	profile_update();
 	device_unregister(ppdev);
 
 cleanup_ida:
@@ -726,15 +752,33 @@ static int __init platform_profile_init(void)
 	if (err)
 		return err;
 
+	profile_kobj = kobject_create_and_add("platform_profile", kernel_kobj);
+	if (!profile_kobj) {
+		err = -ENOMEM;
+		goto unregister_class;
+	}
+
+	err = sysfs_create_group(profile_kobj, &aggregate_group);
+	if (err)
+		goto put_kobj;
+
 	compat_kobj = platform_profile_compat_kobj();
 	if (compat_kobj) {
 		err = sysfs_create_group(compat_kobj, &platform_profile_group);
 		if (err) {
 			kobject_put(compat_kobj);
-			class_unregister(&platform_profile_class);
+			goto remove_group;
 		}
 	}
 
+	return 0;
+
+remove_group:
+	sysfs_remove_group(profile_kobj, &aggregate_group);
+put_kobj:
+	kobject_put(profile_kobj);
+unregister_class:
+	class_unregister(&platform_profile_class);
 	return err;
 }
 
@@ -744,6 +788,8 @@ static void __exit platform_profile_exit(void)
 		sysfs_remove_group(compat_kobj, &platform_profile_group);
 		kobject_put(compat_kobj);
 	}
+	sysfs_remove_group(profile_kobj, &aggregate_group);
+	kobject_put(profile_kobj);
 	class_unregister(&platform_profile_class);
 }
 subsys_initcall_sync(platform_profile_init);
-- 
2.43.0