Re: [hwmon-next PATCH v4 3/4] hwmon: (adt7470) Expose fan control via PWM framework

On 7/28/26 21:46, Luiz Angelo Daros de Luca wrote:
> The ADT7470 features four PWM outputs designed to control fans.
> Previously, these were only accessible through the legacy hwmon
> sysfs interface.
> 
> Expose the ADT7470 fan control lines through the generic PWM framework.
> This allows generic PWM consumers described in Device Tree, such as
> "pwm-fan", to use the device through the "#pwm-cells" property.  This is
> particularly necessary for boards where the ADT7470 external temperature
> sensors are not populated and the chip is used strictly as a fan
> controller (e.g., Edgecore ECS-2100-52T switches). In such setups,
> delegating control to the generic PWM subsystem allows the kernel's
> thermal framework to manage the fans based on unrelated temperature
> zones, such as internal SoC sensors.
> 
> When a PWM consumer applies a new PWM state, the driver automatically
> switches the corresponding PWM channel to manual mode so that the
> requested duty cycle takes effect. The duty cycle specified by the PWM
> framework is internally converted to the 0-255 scale expected by the
> hardware registers.
> 
> The legacy sysfs interface remains unaffected and operates in parallel.
> 

No, I won't accept this. It has to be either or. A pwm channel modeled as pwm
subsystem channel must not be visible via hwmon attributes.

Guenter