Hi
Am I right in thinking that this adds functionality that has no users in the
kernel at the moment?
2021. október 22., péntek 20:16 keltezéssel, Mario Limonciello írta:
> Allow other drivers to react to determine 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 form of a notifier call.
>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> drivers/acpi/platform_profile.c | 44 +++++++++++++++++++++++++++-----
> include/linux/platform_profile.h | 11 ++++++++
> 2 files changed, 49 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
> index dd2fbf38e414..964e0c9bf70d 100644
> --- a/drivers/acpi/platform_profile.c
> +++ b/drivers/acpi/platform_profile.c
> @@ -21,6 +21,25 @@ 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);
> +
> +void platform_profile_call_notifier(unsigned long action, void *data)
> +{
> + blocking_notifier_call_chain(&platform_profile_chain_head, action, data);
> +}
> +EXPORT_SYMBOL_GPL(platform_profile_call_notifier);
What is the reason for exporting this function?
>
> static ssize_t platform_profile_choices_show(struct device *dev,
> struct device_attribute *attr,
> @@ -49,11 +68,8 @@ 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 +81,28 @@ 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]);
> }
>
> @@ -130,9 +159,12 @@ void platform_profile_notify(void)
> if (!cur_profile)
> return;
> sysfs_notify(acpi_kobj, NULL, "platform_profile");
> + platform_profile_call_notifier(PLATFORM_PROFILE_CHANGED, NULL);
> +
> }
> EXPORT_SYMBOL_GPL(platform_profile_notify);
>
> +
> 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..390d95d47e07 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 +39,14 @@ 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);
> +void platform_profile_call_notifier(unsigned long action, void *data);
> +
> +enum platform_profile_notifier_actions {
> + PLATFORM_PROFILE_CHANGED,
> +};
>
> #endif /*_PLATFORM_PROFILE_H_*/
> --
> 2.25.1
Regards,
Barnabás Pőcze
