[PATCH v4 1/3] ACPI: platform-profile: add platform_profile_cycle()

[Gergo Koteles <soyer@xxxxxx>]

Some laptops have a key to switch platform profiles.

Add a platform_profile_cycle() function to cycle between the enabled
profiles.

Signed-off-by: Gergo Koteles <soyer@xxxxxx>
---
 drivers/acpi/platform_profile.c  | 42 ++++++++++++++++++++++++++++++++
 include/linux/platform_profile.h |  1 +
 2 files changed, 43 insertions(+)

diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
index d418462ab791..1579f380d469 100644
--- a/drivers/acpi/platform_profile.c
+++ b/drivers/acpi/platform_profile.c
@@ -136,6 +136,48 @@ void platform_profile_notify(void)
 }
 EXPORT_SYMBOL_GPL(platform_profile_notify);
 
+int platform_profile_cycle(void)
+{
+	enum platform_profile_option profile;
+	enum platform_profile_option next;
+	int err;
+
+	err = mutex_lock_interruptible(&profile_lock);
+	if (err)
+		return err;
+
+	if (!cur_profile) {
+		mutex_unlock(&profile_lock);
+		return -ENODEV;
+	}
+
+	err = cur_profile->profile_get(cur_profile, &profile);
+	if (err) {
+		mutex_unlock(&profile_lock);
+		return err;
+	}
+
+	next = ffs(cur_profile->choices[0] >> (profile + 1)) + profile;
+
+	/* current profile is the highest, select the lowest */
+	if (next == profile)
+		next = ffs(cur_profile->choices[0]) - 1;
+
+	if (WARN_ON((next < 0) || (next >= ARRAY_SIZE(profile_names)))) {
+		mutex_unlock(&profile_lock);
+		return -EINVAL;
+	}
+
+	err = cur_profile->profile_set(cur_profile, next);
+	mutex_unlock(&profile_lock);
+
+	if (!err)
+		sysfs_notify(acpi_kobj, NULL, "platform_profile");
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(platform_profile_cycle);
+
 int platform_profile_register(struct platform_profile_handler *pprof)
 {
 	int err;
diff --git a/include/linux/platform_profile.h b/include/linux/platform_profile.h
index e5cbb6841f3a..f5492ed413f3 100644
--- a/include/linux/platform_profile.h
+++ b/include/linux/platform_profile.h
@@ -36,6 +36,7 @@ struct platform_profile_handler {
 
 int platform_profile_register(struct platform_profile_handler *pprof);
 int platform_profile_remove(void);
+int platform_profile_cycle(void);
 void platform_profile_notify(void);
 
 #endif  /*_PLATFORM_PROFILE_H_*/
-- 
2.44.0