Re: [PATCH v6 11/14] platform/x86: oxpec: Adhere to sysfs-class-hwmon and enable pwm on 2

Thomas Weißschuh
2025-03-22T08:23:52Z

On 2025-03-19 18:55:06+0100, Antheas Kapenekakis wrote:
> Currently, the driver does not adhere to the sysfs-class-hwmon
> specification: 0 is used for auto fan control and 1 is used for manual
> control. However, it is expected that 0 sets the fan to full speed,
> 1 sets the fan to manual, and then 2 is used for automatic control.
>
> Therefore, change the sysfs API to reflect this and enable pwm on 2.
>
> As we are breaking the ABI for this driver, rename oxpec to oxp_ec,
> reflecting the naming convention used by other drivers, to allow for
> a smooth migration in current userspace programs.

Where is the renaming being done?

> Closes: https://lore.kernel.org/linux-hwmon/20241027174836.8588-1-derekjohn.clark@gmail.com/
> Reviewed-by: Derek J. Clark <derekjohn.clark@gmail.com>
> Signed-off-by: Antheas Kapenekakis <lkml@antheas.dev>
> ---
> drivers/platform/x86/oxpec.c | 35 ++++++++++++++++++++++++++++++++---
> 1 file changed, 32 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/platform/x86/oxpec.c b/drivers/platform/x86/oxpec.c
> index e84afc5f53379..680fa537babf6 100644
> --- a/drivers/platform/x86/oxpec.c
> +++ b/drivers/platform/x86/oxpec.c
> @@ -731,7 +731,27 @@ static int oxp_platform_read(struct device *dev, enum hwmon_sensor_types type,
> case hwmon_pwm_input:
> return oxp_pwm_input_read(val);
> case hwmon_pwm_enable:
> - return oxp_pwm_read(val);
> + ret = oxp_pwm_read(val);
> + if (ret)
> + return ret;
> +
> + /* Check for auto and return 2 */
> + if (!*val) {
> + *val = 2;
> + return 0;
> + }
> +
> + /* Return 0 if at full fan speed, 1 otherwise */
> + ret = oxp_pwm_fan_speed(val);
> + if (ret)
> + return ret;
> +
> + if (*val == 255)
> + *val = 0;
> + else
> + *val = 1;
> +
> + return 0;
> default:
> break;
> }
> @@ -745,15 +765,24 @@ static int oxp_platform_read(struct device *dev, enum hwmon_sensor_types type,
> static int oxp_platform_write(struct device *dev, enum hwmon_sensor_types type,
> u32 attr, int channel, long val)
> {
> + int ret;
> +
> switch (type) {
> case hwmon_pwm:
> switch (attr) {
> case hwmon_pwm_enable:
> if (val == 1)
> return oxp_pwm_enable();
> - else if (val == 0)
> + else if (val == 2)
> return oxp_pwm_disable();
> - return -EINVAL;
> + else if (val != 0)
> + return -EINVAL;
> +
> + /* Enable PWM and set to max speed */
> + ret = oxp_pwm_enable();
> + if (ret)
> + return ret;
> + return oxp_pwm_input_write(255);
> case hwmon_pwm_input:
> return oxp_pwm_input_write(val);
> default:
> --
> 2.48.1
>