Re: [PATCH net-next v2 04/10] net: dsa: lan9303: Added adjust_link() method

[Egil Hjelmeland]

On 26. juli 2017 19:09, Andrew Lunn wrote:
> On Tue, Jul 25, 2017 at 06:15:47PM +0200, Egil Hjelmeland wrote:
> > This makes the driver react to device tree "fixed-link" declaration
> > on CPU port.
> >
> > - turn off autonegotiation
> > - force speed 10 or 100 mb/s
> > - force duplex mode
> >
> > Signed-off-by: Egil Hjelmeland <privat@xxxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/net/dsa/lan9303-core.c | 33 +++++++++++++++++++++++++++++++++
> >   1 file changed, 33 insertions(+)
> >
> > diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c
> > index 0806a0684d55..be6d78f45a5f 100644
> > --- a/drivers/net/dsa/lan9303-core.c
> > +++ b/drivers/net/dsa/lan9303-core.c
> > @@ -17,6 +17,7 @@
> >   #include <linux/regmap.h>
> >   #include <linux/mutex.h>
> >   #include <linux/mii.h>
> > +#include <linux/phy.h>
> >   
> >   #include "lan9303.h"
> >   
> > @@ -746,6 +747,37 @@ static int lan9303_phy_write(struct dsa_switch *ds, int phy, int regnum,
> >   	return chip->ops->phy_write(chip, phy, regnum, val);
> >   }
> >   
> > +static void lan9303_adjust_link(struct dsa_switch *ds, int port,
> > +				struct phy_device *phydev)
> > +{
> > +	struct lan9303 *chip = ds->priv;
> > +
> > +	int ctl, res;
> > +
> > +	ctl = lan9303_phy_read(ds, port, MII_BMCR);
> > +
> > +	if (!phy_is_pseudo_fixed_link(phydev))
> > +		return;
> > +
>
> Hi Egil
>
> Maybe do this check before reading MII_BMCR?

OK

> > +	ctl &= ~BMCR_ANENABLE;
>
> Should this also mask out BMCR_SPEED100 and DUPLEX_FULL? Otherwise how
> do you select 10/Half if it is already configured for 100/Full?

Yes you are right. I started out with setting ctl to the fixed default
value, and later changed code to start by reading it from HW.


> > +	if (phydev->speed == SPEED_100)
> > +		ctl |= BMCR_SPEED100;
> > +
> > +	if (phydev->duplex == DUPLEX_FULL)
> > +		ctl |= BMCR_FULLDPLX;
> > +
> > +	res =  lan9303_phy_write(ds, port, MII_BMCR, ctl);
> > +
> > +	if (port == chip->phy_addr_sel_strap) {
> > +		/* Virtual Phy: Remove Turbo 200Mbit mode */
> > +		lan9303_read(chip->regmap, LAN9303_VIRT_SPECIAL_CTRL, &ctl);
> > +
> > +		ctl &= ~(1 << 10); // TURBO BIT
>
> BIT(10), or better still something like BIT(LAN9303_VIRT_SPECIAL_TURBO)

Agree

> > +		res =  regmap_write(chip->regmap,
> > +				    LAN9303_VIRT_SPECIAL_CTRL, ctl);
> > +	}
> > +}
>
>    Andrew