On 23-07-18, Andrew Lunn wrote:
> On Tue, Jul 18, 2023 at 10:35:04AM +0200, Marco Felsch wrote:
> > On 23-07-18, Andrew Lunn wrote:
> > > On Mon, Jul 17, 2023 at 06:43:07PM +0200, Marco Felsch wrote:
> > > > Add generic phy-supply handling support to control the phy regulator.
> > > > Use the common stmmac_platform code path so all drivers using
> > > > stmmac_probe_config_dt() and stmmac_pltfr_pm_ops can use it.
> > > >
> > > > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> > > > ---
> > > > .../ethernet/stmicro/stmmac/stmmac_platform.c | 51 +++++++++++++++++++
> > > > include/linux/stmmac.h | 1 +
> > > > 2 files changed, 52 insertions(+)
> > > >
> > > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> > > > index eb0b2898daa3d..6193d42b53fb7 100644
> > > > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> > > > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> > > > @@ -10,6 +10,7 @@
> > > >
> > > > #include <linux/platform_device.h>
> > > > #include <linux/pm_runtime.h>
> > > > +#include <linux/regulator/consumer.h>
> > > > #include <linux/module.h>
> > > > #include <linux/io.h>
> > > > #include <linux/of.h>
> > > > @@ -423,6 +424,15 @@ stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac)
> > > > if (plat->interface < 0)
> > > > plat->interface = plat->phy_interface;
> > > >
> > > > + /* Optional regulator for PHY */
> > > > + plat->phy_regulator = devm_regulator_get_optional(&pdev->dev, "phy");
> > > > + if (IS_ERR(plat->phy_regulator)) {
> > > > + if (PTR_ERR(plat->phy_regulator) == -EPROBE_DEFER)
> > > > + return ERR_CAST(plat->phy_regulator);
> > > > + dev_info(&pdev->dev, "No regulator found\n");
> > > > + plat->phy_regulator = NULL;
> > > > + }
> > > > +
> > >
> > > So this gets the regulator. When do you actually turn it on?
> >
> > During the suspend/resume logic like the rockchip, sun8i platform
> > integrations did.
>
> So you are assuming the boot loader has turned it on?
>
> You also might have a difference between the actual state, and what
> kernel thinks the state is, depending on how the regulator is
> implemented.
>
> It would be better to explicitly turn it on before registering the
> MDIO bus.
You're right, I changed this. Thanks for the hint.
Regards,
Marco
