Commit 623cef65 authored by Shengyu Qu's avatar Shengyu Qu Committed by Tony Lindgren
Browse files

ARM: dts: am335x-bone-common: Add GPIO PHY reset on revision C3 board 

This patch adds ethernet PHY reset GPIO config for Beaglebone Black
series boards with revision C3. This fixes a random phy startup failure
bug discussed at [1]. The GPIO pin used for reset is not used on older
revisions, so it is ok to apply to all board revisions. The reset timing
was discussed and tested at [2].

[1] https://forum.digikey.com/t/ethernet-device-is-not-detecting-on-ubuntu-20-04-lts-on-bbg/19948
[2] https://forum.beagleboard.org/t/recognizing-a-beaglebone-black-rev-c3-board/31249/



Signed-off-by: default avatarRobert Nelson <robertcnelson@gmail.com>
Signed-off-by: default avatarShengyu Qu <wiagn233@outlook.com>
Message-ID: <TY3P286MB26113797A3B2EC7E0348BBB2980FA@TY3P286MB2611.JPNP286.PROD.OUTLOOK.COM>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
parent 27c146e3

arch/arm/boot/dts/ti/omap/am335x-bone-common.dtsi

+8 −0
Original line number Diff line number Diff line
@@ -145,6 +145,8 @@ 
			/* MDIO */

			AM33XX_PADCONF(AM335X_PIN_MDIO, PIN_INPUT_PULLUP | SLEWCTRL_FAST, MUX_MODE0)

			AM33XX_PADCONF(AM335X_PIN_MDC, PIN_OUTPUT_PULLUP, MUX_MODE0)

			/* Added to support GPIO controlled PHY reset */

			AM33XX_PADCONF(AM335X_PIN_UART0_CTSN, PIN_OUTPUT_PULLUP, MUX_MODE7)

		>;

	};
@@ -153,6 +155,8 @@ 
			/* MDIO reset value */

			AM33XX_PADCONF(AM335X_PIN_MDIO, PIN_INPUT_PULLDOWN, MUX_MODE7)

			AM33XX_PADCONF(AM335X_PIN_MDC, PIN_INPUT_PULLDOWN, MUX_MODE7)

			/* Added to support GPIO controlled PHY reset */

			AM33XX_PADCONF(AM335X_PIN_UART0_CTSN, PIN_INPUT_PULLDOWN, MUX_MODE7)

		>;

	};
@@ -377,6 +381,10 @@ 


	ethphy0: ethernet-phy@0 {

		reg = <0>;

		/* Support GPIO reset on revision C3 boards */

		reset-gpios = <&gpio1 8 GPIO_ACTIVE_LOW>;

		reset-assert-us = <300>;

		reset-deassert-us = <6500>;

	};

};