Patch "ARM: dts: imx6dl-yapp4: Move the internal switch PHYs under the switch node" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ARM: dts: imx6dl-yapp4: Move the internal switch PHYs under the switch node

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm-dts-imx6dl-yapp4-move-the-internal-switch-phys-u.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit efe55ffd9720f78d2871a1cda267e6bdbfbbd757
Author: Michal Vokáč <michal.vokac@xxxxxxxxx>
Date:   Wed Feb 14 10:03:28 2024 +0100

    ARM: dts: imx6dl-yapp4: Move the internal switch PHYs under the switch node
    
    [ Upstream commit 79978bff2e4b8e05ebdf5fc3ee6b794002393484 ]
    
    We identified that the PHYs actually do not work since commit 7da7b84fee58
    ("ARM: dts: imx6dl-yapp4: Move phy reset into switch node") as
    a coincidence of several circumstances.
    
    The reset signal is kept asserted by a pull-down resistor on the board
    unless it is deasserted by GPIO from the SoC. This is to keep the switch
    dead until it is configured properly by the kernel and user space.
    
    Prior to the referenced commit the switch was reset by the FEC driver
    and the reset GPIO was actively deasserted. The mdio-bus was scanned
    and the attached switch and its PHYs were found and configured.
    
    With the referenced commit the switch is reset by the qca8k driver.
    Because of another bug in the qca8k driver, functionality of the reset
    pin depends on its pre-kernel configuration. See commit c44fc98f0a8f
    ("net: dsa: qca8k: fix illegal usage of GPIO")
    
    The problem did not appear until we removed support for the switch
    and configuration of its reset pin from the bootloader.
    
    To fix that, properly describe the internal mdio-bus configuration of
    the qca8334 switch. The PHYs are internal to the switch and sit on its
    internal mdio-bus.
    
    Fixes: 7da7b84fee58 ("ARM: dts: imx6dl-yapp4: Move phy reset into switch node")
    Signed-off-by: Michal Vokáč <michal.vokac@xxxxxxxxx>
    Signed-off-by: Shawn Guo <shawnguo@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/arm/boot/dts/imx6dl-yapp4-common.dtsi b/arch/arm/boot/dts/imx6dl-yapp4-common.dtsi
index e86f409ca8801..68af441e78948 100644
--- a/arch/arm/boot/dts/imx6dl-yapp4-common.dtsi
+++ b/arch/arm/boot/dts/imx6dl-yapp4-common.dtsi
@@ -108,14 +108,6 @@ mdio {
 		#address-cells = <1>;
 		#size-cells = <0>;
 
-		phy_port2: phy@1 {
-			reg = <1>;
-		};
-
-		phy_port3: phy@2 {
-			reg = <2>;
-		};
-
 		switch@10 {
 			compatible = "qca,qca8334";
 			reg = <0x10>;
@@ -140,15 +132,30 @@ fixed-link {
 				port@2 {
 					reg = <2>;
 					label = "eth2";
+					phy-mode = "internal";
 					phy-handle = <&phy_port2>;
 				};
 
 				port@3 {
 					reg = <3>;
 					label = "eth1";
+					phy-mode = "internal";
 					phy-handle = <&phy_port3>;
 				};
 			};
+
+			mdio {
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				phy_port2: ethernet-phy@1 {
+					reg = <1>;
+				};
+
+				phy_port3: ethernet-phy@2 {
+					reg = <2>;
+				};
+			};
 		};
 	};
 };