kernel/linux.git/Documentation/networking/phy.rst, branch v7.0.10

net: phy: remove unused fixup unregistering functions

2026-01-16T03:48:26+00:00

No user of PHY fixups unregisters these. IOW: The fixup unregistering functions are unused and can be removed. Remove also documentation for these functions. Whilst at it, remove also mentioning of phy_register_fixup() from the Documentation, as this function has been static since ea47e70e476f ("net: phy: remove fixup-related definitions from phy.h which are not used outside phylib"). Fixup unregistering functions were added with f38e7a32ee4f ("phy: add phy fixup unregister functions") in 2016, and last user was removed with 6782d06a47ad ("net: usb: lan78xx: Remove KSZ9031 PHY fixup") in 2024. Signed-off-by: Heiner Kallweit Link: https://patch.msgid.link/ff8ac321-435c-48d0-b376-fbca80c0c22e@gmail.com Signed-off-by: Jakub Kicinski

Revert "Documentation: net: add flow control guide and document ethtool API"

2025-10-01T07:48:21+00:00

This reverts commit 7bd80ed89d72285515db673803b021469ba71ee8. I should not have merged it to begin with due to pending review and changes to be addressed. Link: https://patch.msgid.link/c6f3af12df9b7998920a02027fc8893ce82afc4c.1759239721.git.pabeni@redhat.com Signed-off-by: Paolo Abeni

Documentation: net: add flow control guide and document ethtool API

2025-09-30T07:48:31+00:00

Introduce a new document, flow_control.rst, to provide a comprehensive guide on Ethernet Flow Control in Linux. The guide explains how flow control works, how autonegotiation resolves pause capabilities, and how to configure it using ethtool and Netlink. In parallel, document the pause and pause-stat attributes in the ethtool.yaml netlink spec. This enables the ynl tool to generate kernel-doc comments for the corresponding enums in the UAPI header, making the C interface self-documenting. Finally, replace the legacy flow control section in phy.rst with a reference to the new document and add pointers in the relevant C source files. Signed-off-by: Oleksij Rempel Link: https://patch.msgid.link/20250924120241.724850-1-o.rempel@pengutronix.de Signed-off-by: Paolo Abeni

docs: networking: phy: clarify abbreviation "PAL"

2025-09-29T19:10:19+00:00

It is suddenly used in the text without introduction, so the meaning might have been unclear to readers. Signed-off-by: Markus Heidelberg Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/20250926131520.222346-1-m.heidelberg@cab.de Signed-off-by: Jakub Kicinski

net: phy: MII-Lite PHY interface mode

2025-07-10T02:32:30+00:00

Some Broadcom PHYs are capable to operate in simplified MII mode, without TXER, RXER, CRS and COL signals as defined for the MII. The MII-Lite mode can be used on most Ethernet controllers with full MII interface by just leaving the input signals (RXER, CRS, COL) inactive. The absence of COL signal makes half-duplex link modes impossible but does not interfere with BroadR-Reach link modes on Broadcom PHYs, because they are all full-duplex only. Add MII-Lite interface mode, especially for Broadcom two-wire PHYs. Signed-off-by: Kamil Horák - 2N Reviewed-by: Maxime Chevallier Reviewed-by: Florian Fainelli Reviewed-by: Russell King (Oracle) Link: https://patch.msgid.link/20250708090140.61355-2-kamilh@axis.com Signed-off-by: Jakub Kicinski

net: phy: introduce core support for phy-mode = "10g-qxgmii"

2024-06-18T11:28:26+00:00

10G-QXGMII is a MAC-to-PHY interface defined by the USXGMII multiport specification. It uses the same signaling as USXGMII, but it multiplexes 4 ports over the link, resulting in a maximum speed of 2.5G per port. Some in-tree SoCs like the NXP LS1028A use "usxgmii" when they mean either the single-port USXGMII or the quad-port 10G-QXGMII variant, and they could get away just fine with that thus far. But there is a need to distinguish between the 2 as far as SerDes drivers are concerned. Signed-off-by: Vladimir Oltean Signed-off-by: Luo Jie Reviewed-by: Andrew Lunn Reviewed-by: Russell King (Oracle) Signed-off-by: Paolo Abeni

net: phy: Introduce PSGMII PHY interface mode

2023-08-14T07:12:53+00:00

The PSGMII interface is similar to QSGMII. The main difference is that the PSGMII interface combines five SGMII lines into a single link while in QSGMII only four lines are combined. Similarly to the QSGMII, this interface mode might also needs special handling within the MAC driver. It is commonly used by Qualcomm with their QCA807x PHY series and modern WiSoC-s. Add definitions for the PHY layer to allow to express this type of connection between the MAC and PHY. Signed-off-by: Gabor Juhos Signed-off-by: Robert Marko Signed-off-by: David S. Miller

Documentation: networking: correct spelling

2023-01-31T12:00:47+00:00

Correct spelling problems for Documentation/networking/ as reported by codespell. Signed-off-by: Randy Dunlap Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Cc: Jiri Pirko Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: netdev@vger.kernel.org Link: https://lore.kernel.org/r/20230129231053.20863-5-rdunlap@infradead.org Signed-off-by: Paolo Abeni

docs: networking: phy: add missing space

2022-10-06T03:32:39+00:00

Missing space between "pins'" and "strength" Signed-off-by: Casper Andersson Reviewed-by: Bagas Sanjaya Link: https://lore.kernel.org/r/20221004073242.304425-1-casper.casan@gmail.com Signed-off-by: Jakub Kicinski

net: phy: Add 1000BASE-KX interface mode

2022-09-05T13:30:42+00:00

Add 1000BASE-KX interface mode. This 1G backplane ethernet as described in clause 70. Clause 73 autonegotiation is mandatory, and only full duplex operation is supported. Although at the PMA level this interface mode is identical to 1000BASE-X, it uses a different form of in-band autonegation. This justifies a separate interface mode, since the interface mode (along with the MLO_AN_* autonegotiation mode) sets the type of autonegotiation which will be used on a link. This results in more than just electrical differences between the link modes. With regard to 1000BASE-X, 1000BASE-KX holds a similar position to SGMII: same signaling, but different autonegotiation. PCS drivers (which typically handle in-band autonegotiation) may only support 1000BASE-X, and not 1000BASE-KX. Similarly, the phy mode is used to configure serdes phys with phy_set_mode_ext. Due to the different electrical standards (SFI or XFI vs Clause 70), they will likely want to use different configuration. Adding a phy interface mode for 1000BASE-KX helps simplify configuration in these areas. Signed-off-by: Sean Anderson Signed-off-by: David S. Miller