Re: [hwmon PATCH v3 6/6] hwmon: (adt7470) Use cached PWM frequency value

[Guenter Roeck]

On 7/26/26 20:34, Luiz Angelo Daros de Luca wrote:
> adt7470_pwm_read() currently ignores failures returned by
> pwm1_freq_get(). If the register read fails, the negative error code is
> returned through *val while the function itself reports success,
> potentially exposing a negative PWM frequency through sysfs.
>
> Fix this by using the cached PWM frequency maintained by the driver,
> eliminating the register access from the read path.
>
> Apart from the corrected error propagation and using the cached value,
> no functional change is intended.

An alternative might be to use regmap for caching and drop all driver-internal
caching. I have done that for other drivers; typically it simplifies the code,
sometimes significantly, since the update_device() function is no longer needed.
Something to consider for later, maybe.

Thanks,
Guenter