Home
last modified time | relevance | path

Searched hist:"3 f2628d6" (Results 1 – 1 of 1) sorted by relevance

/openbmc/linux/drivers/net/dsa/ocelot/
H A Dfelix_vsc9959.c3f2628d6 Sun Jul 05 11:16:21 CDT 2020 Vladimir Oltean <vladimir.oltean@nxp.com> net: dsa: felix: clarify the intention of writes to MII_BMCR

The driver appears to write to BMCR_SPEED and BMCR_DUPLEX, fields which
are read-only, since they are actually configured through the
vendor-specific IF_MODE (0x14) register.

But the reason we're writing back the read-only values of MII_BMCR is to
alter these writable fields:

BMCR_RESET
BMCR_LOOPBACK
BMCR_ANENABLE
BMCR_PDOWN
BMCR_ISOLATE
BMCR_ANRESTART

In particular, the only field which is really relevant to this driver is
BMCR_ANENABLE. Clarify that intention by spelling it out, using
phy_set_bits and phy_clear_bits.

The driver also made a few writes to BMCR_RESET and BMCR_ANRESTART which
are unnecessary and may temporarily disrupt the link to the PHY. Remove
them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
3f2628d6 Sun Jul 05 11:16:21 CDT 2020 Vladimir Oltean <vladimir.oltean@nxp.com> net: dsa: felix: clarify the intention of writes to MII_BMCR

The driver appears to write to BMCR_SPEED and BMCR_DUPLEX, fields which
are read-only, since they are actually configured through the
vendor-specific IF_MODE (0x14) register.

But the reason we're writing back the read-only values of MII_BMCR is to
alter these writable fields:

BMCR_RESET
BMCR_LOOPBACK
BMCR_ANENABLE
BMCR_PDOWN
BMCR_ISOLATE
BMCR_ANRESTART

In particular, the only field which is really relevant to this driver is
BMCR_ANENABLE. Clarify that intention by spelling it out, using
phy_set_bits and phy_clear_bits.

The driver also made a few writes to BMCR_RESET and BMCR_ANRESTART which
are unnecessary and may temporarily disrupt the link to the PHY. Remove
them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>