public inbox for linux-acpi@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH v2] ACPI: platform_profile: Add support for notification chains
@ 2021-10-25 21:03 Mario Limonciello
  2021-10-26 11:31 ` kernel test robot
  2021-10-29  0:58 ` kernel test robot
  0 siblings, 2 replies; 3+ messages in thread
From: Mario Limonciello @ 2021-10-25 21:03 UTC (permalink / raw)
  To: Rafael J . Wysocki, linux-acpi; +Cc: markpearson, pobrn, Mario Limonciello

Allow other drivers to initialize relative to current active
profile and react to platform profile changes.

Drivers wishing to utilize this should register for notification
at module load and unregister when unloading.

Notifications will come in the from a notifier call.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
V1: https://lore.kernel.org/linux-acpi/7d0c7f12-a412-582e-22f2-8285cf74066a@amd.com/T/#m834d32b2ebcf8bd3dab0c5aa48f6deaa48e34e62
Changes from v1->v2:
 * Add the new performance mode as part of the callback to simplify callers.
 * Drop the GPL symbol export for platform_profile_call_notifier

 drivers/acpi/platform_profile.c  | 48 ++++++++++++++++++++++++++++----
 include/linux/platform_profile.h | 10 +++++++
 2 files changed, 52 insertions(+), 6 deletions(-)

diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
index dd2fbf38e414..1badbc8d6012 100644
--- a/drivers/acpi/platform_profile.c
+++ b/drivers/acpi/platform_profile.c
@@ -21,6 +21,24 @@ static const char * const profile_names[] = {
 	[PLATFORM_PROFILE_PERFORMANCE] = "performance",
 };
 static_assert(ARRAY_SIZE(profile_names) == PLATFORM_PROFILE_LAST);
+static BLOCKING_NOTIFIER_HEAD(platform_profile_chain_head);
+
+int platform_profile_register_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&platform_profile_chain_head, nb);
+}
+EXPORT_SYMBOL_GPL(platform_profile_register_notifier);
+
+int platform_profile_unregister_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&platform_profile_chain_head, nb);
+}
+EXPORT_SYMBOL_GPL(platform_profile_unregister_notifier);
+
+static void platform_profile_call_notifier(unsigned long action, void *data)
+{
+	blocking_notifier_call_chain(&platform_profile_chain_head, action, data);
+}
 
 static ssize_t platform_profile_choices_show(struct device *dev,
 					struct device_attribute *attr,
@@ -49,11 +67,8 @@ static ssize_t platform_profile_choices_show(struct device *dev,
 	return len;
 }
 
-static ssize_t platform_profile_show(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
+int platform_profile_get(enum platform_profile_option *profile)
 {
-	enum platform_profile_option profile = PLATFORM_PROFILE_BALANCED;
 	int err;
 
 	err = mutex_lock_interruptible(&profile_lock);
@@ -65,15 +80,28 @@ static ssize_t platform_profile_show(struct device *dev,
 		return -ENODEV;
 	}
 
-	err = cur_profile->profile_get(cur_profile, &profile);
+	err = cur_profile->profile_get(cur_profile, profile);
 	mutex_unlock(&profile_lock);
 	if (err)
 		return err;
 
 	/* Check that profile is valid index */
-	if (WARN_ON((profile < 0) || (profile >= ARRAY_SIZE(profile_names))))
+	if (WARN_ON((*profile < 0) || (*profile >= ARRAY_SIZE(profile_names))))
 		return -EIO;
 
+	return 0;
+}
+EXPORT_SYMBOL_GPL(platform_profile_get);
+
+static ssize_t platform_profile_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	enum platform_profile_option profile = PLATFORM_PROFILE_BALANCED;
+	int ret = platform_profile_get(&profile);
+
+	if (ret)
+		return ret;
 	return sysfs_emit(buf, "%s\n", profile_names[profile]);
 }
 
@@ -127,9 +155,17 @@ static const struct attribute_group platform_profile_group = {
 
 void platform_profile_notify(void)
 {
+	enum platform_profile_option profile;
+	int ret;
+
 	if (!cur_profile)
 		return;
 	sysfs_notify(acpi_kobj, NULL, "platform_profile");
+	ret = platform_profile_get(&profile);
+	if (ret)
+		return;
+	platform_profile_call_notifier(PLATFORM_PROFILE_CHANGED, &profile);
+
 }
 EXPORT_SYMBOL_GPL(platform_profile_notify);
 
diff --git a/include/linux/platform_profile.h b/include/linux/platform_profile.h
index e5cbb6841f3a..05ba3403509a 100644
--- a/include/linux/platform_profile.h
+++ b/include/linux/platform_profile.h
@@ -11,6 +11,8 @@
 
 #include <linux/bitops.h>
 
+struct notifier_block;
+
 /*
  * If more options are added please update profile_names array in
  * platform_profile.c and sysfs-platform_profile documentation.
@@ -37,5 +39,13 @@ struct platform_profile_handler {
 int platform_profile_register(struct platform_profile_handler *pprof);
 int platform_profile_remove(void);
 void platform_profile_notify(void);
+int platform_profile_get(enum platform_profile_option *profile);
+
+int platform_profile_register_notifier(struct notifier_block *nb);
+int platform_profile_unregister_notifier(struct notifier_block *nb);
+
+enum platform_profile_notifier_actions {
+	PLATFORM_PROFILE_CHANGED,
+};
 
 #endif  /*_PLATFORM_PROFILE_H_*/
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-10-29  0:59 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-10-25 21:03 [PATCH v2] ACPI: platform_profile: Add support for notification chains Mario Limonciello
2021-10-26 11:31 ` kernel test robot
2021-10-29  0:58 ` kernel test robot

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox