RE: [PATCH] net: phy: micrel: workaround to NAND_Tree# incorrectly strapp-in during the reset period.

[Yang, Wenyou]

> -----Original Message-----
> From: Florian Fainelli [mailto:f.fainelli@xxxxxxxxx]
> Sent: Monday, December 08, 2014 1:09 PM
> To: Yang, Wenyou
> Cc: netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Ferre, Nicolas; linux-
> arm-kernel-bounces@xxxxxxxxxxxxxxxxxxx; johan@xxxxxxxxxx
> Subject: Re: [PATCH] net: phy: micrel: workaround to NAND_Tree# incorrectly
> strapp-in during the reset period.
> 
> Le 07/12/2014 19:35, Wenyou Yang a Ãcrit :
> > Appearance: On some boards, after power up, the Ethernet doesn't work.
> >
> > Reason: On the SAMA5D4EK, the PIOE2 pin is connected to the NAND_Tree#
> > of KSZ8081, But it outputs LOW during the reset period, which cause the
> NAND_Tree# enabled.
> >
> > Workaround: In the .config_init(), add code to disable NAND_Tree# by
> > operating Operation Mode Strap Override(i.e. Register 16h).
> 
> Your patch won't apply cleanly to the net-next tree where the PHY drivers
> development is happening, especially not after Johan's recent changes.
> 
> Is not what you are looking for a phy_fixup() rather than clearing this bit for all
> Micrel PHYs?
Thanks, I will go in this direction.

> 
> >
> > Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx>
> > ---
> >  drivers/net/phy/micrel.c |    8 +++++++-
> >  1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c index
> > 8c2a29a..11d72cb 100644
> > --- a/drivers/net/phy/micrel.c
> > +++ b/drivers/net/phy/micrel.c
> > @@ -31,6 +31,7 @@
> >  /* Operation Mode Strap Override */
> >  #define MII_KSZPHY_OMSO				0x16
> >  #define KSZPHY_OMSO_B_CAST_OFF			(1 << 9)
> > +#define KSZPHY_OMSO_NAND_TREE_OVERRIDE		(1 << 5)
> >  #define KSZPHY_OMSO_RMII_OVERRIDE		(1 << 1)
> >  #define KSZPHY_OMSO_MII_OVERRIDE		(1 << 0)
> >
> > @@ -180,7 +181,12 @@ static int kszphy_setup_led(struct phy_device
> > *phydev,
> >
> >  static int kszphy_config_init(struct phy_device *phydev)  {
> > -	return 0;
> > +	int rc;
> > +
> > +	phy_write(phydev, MII_KSZPHY_OMSO, phy_read(phydev,
> MII_KSZPHY_OMSO)
> > +			& (~KSZPHY_OMSO_NAND_TREE_OVERRIDE));
> > +	rc = ksz_config_flags(phydev);
> > +	return rc < 0 ? rc : 0;
> >  }
> >
> >  static int kszphy_config_init_led8041(struct phy_device *phydev)
> >

Best Regards,
Wenyou Yang