Re: [PATCH v2 18/18] ACPI: platform_profile: Add documentation

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Tue, 14 Jan 2025, Kurt Borja wrote:

> Add kerneldoc and sysfs class documentation.
> 
> Signed-off-by: Kurt Borja <kuurtb@gmail.com>
> ---
>  .../ABI/testing/sysfs-class-platform-profile  | 44 +++++++++++++++++++
>  drivers/acpi/platform_profile.c               | 33 ++++++++++++++
>  include/linux/platform_profile.h              | 24 ++++++++++
>  3 files changed, 101 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-class-platform-profile
> 
> diff --git a/Documentation/ABI/testing/sysfs-class-platform-profile b/Documentation/ABI/testing/sysfs-class-platform-profile
> new file mode 100644
> index 000000000000..b5a3600080bc
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-class-platform-profile
> @@ -0,0 +1,44 @@
> +What:		/sys/class/platform-profile/platform-profile-X/name
> +Date:		January 2025
> +Description:	Name of the class device given by the driver.
> +
> +		RO
> +
> +What:		/sys/class/platform-profile/platform-profile-X/choices
> +Date:		January 2025
> +Description:	This file contains a space-separated list of profiles supported for this device.
> +
> +		Drivers must use the following standard profile-names:
> +
> +		====================	========================================
> +		low-power		Low power consumption
> +		cool			Cooler operation
> +		quiet			Quieter operation
> +		balanced		Balance between low power consumption
> +					and performance
> +		balanced-performance	Balance between performance and low
> +					power consumption with a slight bias
> +					towards performance
> +		performance		High performance operation
> +		custom			Driver defined custom profile
> +		====================	========================================
> +
> +		RO
> +
> +What:		/sys/class/platform-profile/platform-profile-X/profile
> +Date:		January 2025
> +Description:	Reading this file gives the current selected profile for this
> +		device. Writing this file with one of the strings from
> +		platform_profile_choices changes the profile to the new value.
> +
> +		This file can be monitored for changes by polling for POLLPRI,
> +		POLLPRI will be signaled on any changes, independent of those
> +		changes coming from a userspace write; or coming from another
> +		source such as e.g. a hotkey triggered profile change handled
> +		either directly by the embedded-controller or fully handled
> +		inside the kernel.
> +
> +		This file may also emit the string 'custom' to indicate
> +		that the driver is using a driver defined custom profile.
> +
> +		RW
> diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
> index c44989801f8e..9caddac695b8 100644
> --- a/drivers/acpi/platform_profile.c
> +++ b/drivers/acpi/platform_profile.c
> @@ -426,6 +426,10 @@ static const struct attribute_group platform_profile_group = {
>  	.is_visible = profile_class_is_visible,
>  };
>  
> +/**
> + * platform_profile_notify - Notify class device and legacy sysfs interface
> + * @dev: The class device
> + */
>  void platform_profile_notify(struct device *dev)
>  {
>  	scoped_cond_guard(mutex_intr, return, &profile_lock) {
> @@ -435,6 +439,11 @@ void platform_profile_notify(struct device *dev)
>  }
>  EXPORT_SYMBOL_GPL(platform_profile_notify);
>  
> +/**
> + * platform_profile_cycle - Cycles profiles available on all registered class devices
> + *
> + * Return: 0 on success, -errno on failure
> + */
>  int platform_profile_cycle(void)
>  {
>  	enum platform_profile_option next = PLATFORM_PROFILE_LAST;
> @@ -478,6 +487,15 @@ int platform_profile_cycle(void)
>  }
>  EXPORT_SYMBOL_GPL(platform_profile_cycle);
>  
> +/**
> + * platform_profile_register - Creates and registers a platform profile class device
> + * @dev: Parent device
> + * @name: Name of the class device
> + * @drvdata: Driver data that will be attached to the class device
> + * @ops: Platform profile's mandatory operations
> + *
> + * Return: pointer to the new class device on success, ERR_PTR on failure
> + */
>  struct device *platform_profile_register(struct device *dev, const char *name,
>  					 void *drvdata,
>  					 const struct platform_profile_ops *ops)
> @@ -544,6 +562,12 @@ struct device *platform_profile_register(struct device *dev, const char *name,
>  }
>  EXPORT_SYMBOL_GPL(platform_profile_register);
>  
> +/**
> + * platform_profile_remove - Unregisters a platform profile class device
> + * @dev: Class device
> + *
> + * Return: 0
> + */
>  int platform_profile_remove(struct device *dev)
>  {
>  	struct platform_profile_handler *pprof = to_pprof_handler(dev);
> @@ -569,6 +593,15 @@ static void devm_platform_profile_release(struct device *dev, void *res)
>  	platform_profile_remove(*ppdev);
>  }
>  
> +/**
> + * devm_platform_profile_register - Device managed version of platform_profile_register
> + * @dev: Parent device
> + * @name: Name of the class device
> + * @drvdata: Driver data that will be attached to the class device
> + * @ops: Platform profile's mandatory operations
> + *
> + * Return: pointer to the new class device on success, ERR_PTR on failure
> + */
>  struct device *devm_platform_profile_register(struct device *dev, const char *name,
>  					      void *drvdata,
>  					      const struct platform_profile_ops *ops)
> diff --git a/include/linux/platform_profile.h b/include/linux/platform_profile.h
> index eea1daf85616..eb4dc85dc18c 100644
> --- a/include/linux/platform_profile.h
> +++ b/include/linux/platform_profile.h
> @@ -28,6 +28,30 @@ enum platform_profile_option {
>  	PLATFORM_PROFILE_LAST, /*must always be last */
>  };
>  
> +/**
> + * struct platform_profile_ops - platform profile operations
> + * @probe:	Callback to setup choices available to the new class device.
> + *		Parameters are:
> + *		@drvdata: drvdata pointer passed to platform_profile_register.
> + *		@choices: Empty choices bitmap which the driver has to manually
> + *			  setup, by using set_bit() in bits corresponding to
> + *			  platform_profile_option values. These values will only
> + *			  be enforced when a new profile is selected from
> + *			  user-space.
> + * @profile_get: Callback that will be called when showing the current platform
> + *		 profile.
> + *		 Parameters are:
> + *		 @dev: Class device.
> + *		 @profile: Pointer to the profile which will be read from
> + *			   user-space. Selected choices are not enforced when
> + *			   modifying this value.
> + * @profile_set: Callback that will be called when storing the new platform
> + *		 profile.
> + *		 Parameters are:
> + *		 @dev: Class device.
> + *		 @profile: New platform profile to be set. Guaranteed to be a
> + *			   value selected in the @probe callback.

Does kerneldoc render this sensibly?

> + */
>  struct platform_profile_ops {
>  	int (*probe)(void *drvdata, unsigned long *choices);
>  	int (*profile_get)(struct device *dev, enum platform_profile_option *profile);
> 

-- 
 i.