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From:   Bartosz Golaszewski <bgolaszewski@baylibre.com>
Date:   Tue, 23 Jun 2020 11:46:15 +0200
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Subject: Re: [PATCH 14/15] net: phy: add PHY regulator support
To:     Russell King - ARM Linux admin <linux@armlinux.org.uk>
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wt., 23 cze 2020 o 11:43 Russell King - ARM Linux admin
<linux@armlinux.org.uk> napisa=C5=82(a):
>
> On Tue, Jun 23, 2020 at 11:41:11AM +0200, Bartosz Golaszewski wrote:
> > pon., 22 cze 2020 o 15:29 Russell King - ARM Linux admin
> > <linux@armlinux.org.uk> napisa=C5=82(a):
> > >
> >
> > [snip!]
> >
> > >
> > > This is likely to cause issues for some PHY drivers.  Note that we ha=
ve
> > > some PHY drivers which register a temperature sensor in the probe
> > > function, which means they can be accessed independently of the lifet=
ime
> > > of the PHY bound to the network driver (which may only be while the
> > > network device is "up".)  We certainly do not want hwmon failing just
> > > because the network device is down.
> > >
> > > That's kind of worked around for the reset stuff, because there are t=
wo
> > > layers to that: the mdio device layer reset support which knows nothi=
ng
> > > of the PHY binding state to the network driver, and the phylib reset
> > > support, but it is not nice.
> > >
> >
> > Regulators are reference counted so if the hwmon driver enables it
> > using mdio_device_power_on() it will stay on even after the PHY driver
> > calls phy_device_power_off(), right? Am I missing something?
>
> If that is true, you will need to audit the PHY drivers to add that.
>

This change doesn't have any effect on devices which don't have a
regulator assigned in DT though. The one I'm adding in the last patch
is the first to use this.

Bart