Re: [PATCH 3/4] net: sfp: assume that LOS is not implemented if both LOS normal and inverted is set

Pali Rohár
2020-12-30T16:58:58Z

On Wednesday 30 December 2020 16:13:10 Russell King - ARM Linux admin wrote:
> On Wed, Dec 30, 2020 at 04:47:54PM +0100, Pali Rohár wrote:
> > Some GPON SFP modules (e.g. Ubiquiti U-Fiber Instant) have set both
> > SFP_OPTIONS_LOS_INVERTED and SFP_OPTIONS_LOS_NORMAL bits in their EEPROM.
> >
> > Such combination of bits is meaningless so assume that LOS signal is not
> > implemented.
> >
> > This patch fixes link carrier for GPON SFP module Ubiquiti U-Fiber Instant.
> >
> > Co-developed-by: Russell King <rmk+kernel@armlinux.org.uk>
> > Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
>
> No, this is not co-developed. The patch content is exactly what _I_
> sent you, only the commit description is your own.

Sorry, in this case I misunderstood usage of this Co-developed-by tag.
I will remove it in next iteration of patches.

> > Signed-off-by: Pali Rohár <pali@kernel.org>
> > ---
> > drivers/net/phy/sfp.c | 36 ++++++++++++++++++++++--------------
> > 1 file changed, 22 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
> > index 73f3ecf15260..d47485ed239c 100644
> > --- a/drivers/net/phy/sfp.c
> > +++ b/drivers/net/phy/sfp.c
> > @@ -1475,15 +1475,19 @@ static void sfp_sm_link_down(struct sfp *sfp)
> >
> > static void sfp_sm_link_check_los(struct sfp *sfp)
> > {
> > - unsigned int los = sfp->state & SFP_F_LOS;
> > + const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
> > + const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
> > + __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
> > + bool los = false;
> >
> > /* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
> > - * are set, we assume that no LOS signal is available.
> > + * are set, we assume that no LOS signal is available. If both are
> > + * set, we assume LOS is not implemented (and is meaningless.)
> > */
> > - if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED))
> > - los ^= SFP_F_LOS;
> > - else if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL)))
> > - los = 0;
> > + if (los_options == los_inverted)
> > + los = !(sfp->state & SFP_F_LOS);
> > + else if (los_options == los_normal)
> > + los = !!(sfp->state & SFP_F_LOS);
> >
> > if (los)
> > sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
> > @@ -1493,18 +1497,22 @@ static void sfp_sm_link_check_los(struct sfp *sfp)
> >
> > static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
> > {
> > - return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
> > - event == SFP_E_LOS_LOW) ||
> > - (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
> > - event == SFP_E_LOS_HIGH);
> > + const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
> > + const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
> > + __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
> > +
> > + return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
> > + (los_options == los_normal && event == SFP_E_LOS_HIGH);
> > }
> >
> > static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
> > {
> > - return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
> > - event == SFP_E_LOS_HIGH) ||
> > - (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
> > - event == SFP_E_LOS_LOW);
> > + const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
> > + const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
> > + __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
> > +
> > + return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
> > + (los_options == los_normal && event == SFP_E_LOS_LOW);
> > }
> >
> > static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
> > --
> > 2.20.1
> >
> >
>
> --
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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