diff mbox series

[net-next,v5,1/2] dt-bindings: net: ethernet-phy: Add timing-role role property for ethernet PHYs

Message ID 20241004090100.1654353-2-o.rempel@pengutronix.de (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series net: phy: Support master-slave config via device tree | expand

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Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5 this patch: 5
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 5 this patch: 5
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 3 this patch: 3
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 27 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-10-05--03-00 (tests: 774)

Commit Message

Oleksij Rempel Oct. 4, 2024, 9 a.m. UTC 
This patch introduces a new `timing-role` property in the device tree
bindings for configuring the master/slave role of PHYs. This is
essential for scenarios where hardware strap pins are unavailable or
incorrectly configured.

The `timing-role` property supports the following values:
- `forced-master`: Forces the PHY to operate as a master (clock source).
- `forced-slave`: Forces the PHY to operate as a slave (clock receiver).
- `preferred-master`: Prefers the PHY to be master but allows negotiation.
- `preferred-slave`: Prefers the PHY to be slave but allows negotiation.

The terms "master" and "slave" are retained in this context to align
with the IEEE 802.3 standards, where they are used to describe the roles
of PHY devices in managing clock signals for data transmission. In
particular, the terms are used in specifications for 1000Base-T and
MultiGBASE-T PHYs, among others. Although there is an effort to adopt
more inclusive terminology, replacing these terms could create
discrepancies between the Linux kernel and the established standards,
documentation, and existing hardware interfaces.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
---
changes v5:
- s/force-/forced-(/g
- s/prefer-/preferred-/g
changes v4:
- add "Reviewed-by: Rob Herring (Arm) <robh@kernel.org>"
changes v3:
- rename "master-slave" to "timing-role"
changes v2:
- use string property instead of multiple flags

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 .../devicetree/bindings/net/ethernet-phy.yaml | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)

Comments

Divya Koppera Oct. 4, 2024, 10:33 a.m. UTC | #1 
> This patch introduces a new `timing-role` property in the device tree bindings
> for configuring the master/slave role of PHYs. This is essential for scenarios
> where hardware strap pins are unavailable or incorrectly configured.
> 
> The `timing-role` property supports the following values:
> - `forced-master`: Forces the PHY to operate as a master (clock source).
> - `forced-slave`: Forces the PHY to operate as a slave (clock receiver).
> - `preferred-master`: Prefers the PHY to be master but allows negotiation.
> - `preferred-slave`: Prefers the PHY to be slave but allows negotiation.
> 
> The terms "master" and "slave" are retained in this context to align with the
> IEEE 802.3 standards, where they are used to describe the roles of PHY devices
> in managing clock signals for data transmission. In particular, the terms are
> used in specifications for 1000Base-T and MultiGBASE-T PHYs, among others.
> Although there is an effort to adopt more inclusive terminology, replacing
> these terms could create discrepancies between the Linux kernel and the
> established standards, documentation, and existing hardware interfaces.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
> ---
> changes v5:
> - s/force-/forced-(/g
> - s/prefer-/preferred-/g
> changes v4:
> - add "Reviewed-by: Rob Herring (Arm) <robh@kernel.org>"
> changes v3:
> - rename "master-slave" to "timing-role"
> changes v2:
> - use string property instead of multiple flags
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> ---

Reviewed-by: Divya Koppera <divya.koppera@microchip.com>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
index d9b62741a2259..2c71454ae8e36 100644
--- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
@@ -158,6 +158,27 @@  properties:
       Mark the corresponding energy efficient ethernet mode as
       broken and request the ethernet to stop advertising it.
 
+  timing-role:
+    $ref: /schemas/types.yaml#/definitions/string
+    enum:
+      - forced-master
+      - forced-slave
+      - preferred-master
+      - preferred-slave
+    description: |
+      Specifies the timing role of the PHY in the network link. This property is
+      required for setups where the role must be explicitly assigned via the
+      device tree due to limitations in hardware strapping or incorrect strap
+      configurations.
+      It is applicable to Single Pair Ethernet (1000/100/10Base-T1) and other
+      PHY types, including 1000Base-T, where it controls whether the PHY should
+      be a master (clock source) or a slave (clock receiver).
+
+      - 'forced-master': The PHY is forced to operate as a master.
+      - 'forced-slave': The PHY is forced to operate as a slave.
+      - 'preferred-master': Prefer the PHY to be master but allow negotiation.
+      - 'preferred-slave': Prefer the PHY to be slave but allow negotiation.
+
   pses:
     $ref: /schemas/types.yaml#/definitions/phandle-array
     maxItems: 1