The patch below does not apply to the 6.16-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.16.y git checkout FETCH_HEAD git cherry-pick -x a1b51534b532dd4f0499907865553ee9251bebc3 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025091753-raider-wake-9e9d@gregkh' --subject-prefix 'PATCH 6.16.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From a1b51534b532dd4f0499907865553ee9251bebc3 Mon Sep 17 00:00:00 2001 From: Alex Elder elder@riscstar.com Date: Tue, 12 Aug 2025 22:13:35 -0500 Subject: [PATCH] dt-bindings: serial: 8250: allow "main" and "uart" as clock names

There are two compatible strings defined in "8250.yaml" that require two clocks to be specified, along with their names: - "spacemit,k1-uart", used in "spacemit/k1.dtsi" - "nxp,lpc1850-uart", used in "lpc/lpc18xx.dtsi"

When only one clock is used, the name is not required. However there are two places that do specify a name: - In "mediatek/mt7623.dtsi", the clock for the "mediatek,mtk-btif" compatible serial device is named "main" - In "qca/ar9132.dtsi", the clock for the "ns8250" compatible serial device is named "uart"

In commit d2db0d7815444 ("dt-bindings: serial: 8250: allow clock 'uartclk' and 'reg' for nxp,lpc1850-uart"), Frank Li added the restriction that two named clocks be used for the NXP platform mentioned above.

Change that logic, so that an additional condition for (only) the SpacemiT platform similarly restricts the two clocks to have the names "core" and "bus".

Finally, add "main" and "uart" as allowed names when a single clock is specified.

Fixes: 2c0594f9f0629 ("dt-bindings: serial: 8250: support an optional second clock") Cc: stable stable@kernel.org Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202507160314.wrC51lXX-lkp@intel.com/ Signed-off-by: Alex Elder elder@riscstar.com Acked-by: Conor Dooley conor.dooley@microchip.com Link: https://lore.kernel.org/r/20250813031338.2328392-1-elder@riscstar.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml index f59c0b37e8eb..b243afa69a1a 100644 --- a/Documentation/devicetree/bindings/serial/8250.yaml +++ b/Documentation/devicetree/bindings/serial/8250.yaml @@ -59,7 +59,12 @@ allOf: items: - const: uartclk - const: reg - else: + - if: + properties: + compatible: + contains: + const: spacemit,k1-uart + then: properties: clock-names: items: @@ -183,6 +188,9 @@ properties: minItems: 1 maxItems: 2 oneOf: + - enum: + - main + - uart - items: - const: core - const: bus