net: phy: add phy_query_inband()

Add a method to query the PHY's in-band capabilities for a PHY
interface mode. This can be used to determine for the specified
interface mode whether in-band signalling is supported, and whether
the PHY requires in-band signalling.

When not implemented, or the PHY driver doesn't report any modes
for the interface, LINK_INBAND_VALID will not be set. When set, the
remainder of the flags can be interpreted.

LINK_INBAND_POSSIBLE means that the device can be configured to use
or not use in-band signalling. Later patches may add support to
configure this at the PHY.

LINK_INBAND_REQUIRED means that the device uses in-band signalling
which can not be disabled.

When only LINK_INBAND_VALID has been set, this means that the device
does not support any in-band signalling, and can't be configured to
do so.

"Bypass" mode (where the device may be configured for in-band, but
may still bring the link up if there is no in-band received from the
link partner) is not considered in this patch.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

0 files changed, 0 insertions, 0 deletions