[External] Re: FanPwm interface

[Derek Lin23]

> -----Original Message-----
> From: Lei YU <mine260309 at gmail.com>
> Sent: Friday, November 1, 2019 10:58 AM
> To: Patrick Venture <venture at google.com>
> Cc: Derek Lin23 <dlin23 at lenovo.com>; OpenBMC Maillist
> <openbmc at lists.ozlabs.org>
> Subject: [External] Re: FanPwm interface
> 
> On Fri, Nov 1, 2019 at 6:32 AM Patrick Venture <venture at google.com> wrote:
> >
> > On Thu, Oct 31, 2019 at 3:27 PM Derek Lin23 <dlin23 at lenovo.com> wrote:
> > >
> > > Hi team:
> > >
> > >
> > >
> > >           I have a question regarding of FanPwm interface on hwmon.
> > >
> > >           Does this interface get updated while PWM is changing in
> sysfs?
> > >
> > >           For example, if I setup a fan points to a PWM like below
> configuration, now, FanPwm interface does not get updated when I update
> PWM in sysfs, only my fan inputs (rpms) do.
> > >
> > >
> > >
> > >           Example:
> > >
> > >           LABEL_fan1 = "FAN0_Speed"
> > >
> > >           …
> > >
> > >           PWM_TARGET_fan1 = "1"
> > >
> > >
> > >
> > >           Is there a configuration or label which I can use so FanPwm
> interface would get updated when I change PWM in sysfs?
> >
> > Unless I'm mistaken, it's currently treated only as a Target -- so
> > it's updated only via dbus calls to set it.
> 
> Exactly, it will not update if you change it directly in sysfs.
> This is OK in field because a regular user should access the BMC via
> Redfish/REST API/ipmi.
> 
> But for debugging purpose it does have some trouble that updating pwm in
> sysfs does not reflact on D-Bus.
> So patches are welcome :)

Hi Patrick & Lei:

	Thank you for your comments. Appreciate the help. 

Derek