[openwrt/openwrt] ath79: use gpios for switch management in WZR-HP-G300NH variants

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/70000ab509a0730e842c4b56dd1a505dd53deaa3

commit 70000ab509a0730e842c4b56dd1a505dd53deaa3
Author: Tony Ambardar <itugrok at yahoo.com>
AuthorDate: Mon Jan 16 03:18:00 2023 -0800

    ath79: use gpios for switch management in WZR-HP-G300NH variants
    
    The RTL8366S/RB switch node in DTS defines "mii-bus = <&mdio0>" to permit
    management via SMI but this has likely never worked, instead falling back
    to using GPIOs in the past:
    
         rtl8366s switch: cannot find mdio bus from bus handle (yet)
         rtl8366s switch: using GPIO pins 19 (SDA) and 20 (SCK)
         rtl8366s switch: RTL8366 ver. 1 chip found
    
    Recently, the rtl8366s and rtl8366_smi drivers were changed from built-in
    to loadable modules. This affected driver probing order and caused switch
    initialization (and network access) to fail:
    
         rtl8366s switch: using MDIO bus 'ag71xx_mdio'
         rtl8366s switch: unknown chip id (ffff)
         rtl8366s switch: chip detection failed, err=-19
    
    Force using GPIOs to manage the switch by dropping the "mii-bus" DTS
    definition, which works for both built-in and loadable switch drivers.
    
    Fixes: 6e0f0eae5b ("ath79: use rtl8366s and rtl8366_smi as a module")
    Fixes: 575ec7a4b1 ("ath79: use rtl8366rb as a module")
    Tested-by: Tony Ambardar <itugrok at yahoo.com> # WZR-HP-G300NH (RTL8366S)
    Signed-off-by: Tony Ambardar <itugrok at yahoo.com>
---
 target/linux/ath79/dts/ar9132_buffalo_wzr-hp-g300nh.dtsi | 1 -
 1 file changed, 1 deletion(-)

diff --git a/target/linux/ath79/dts/ar9132_buffalo_wzr-hp-g300nh.dtsi b/target/linux/ath79/dts/ar9132_buffalo_wzr-hp-g300nh.dtsi
index 4443ba583e..ac3af13457 100644
--- a/target/linux/ath79/dts/ar9132_buffalo_wzr-hp-g300nh.dtsi
+++ b/target/linux/ath79/dts/ar9132_buffalo_wzr-hp-g300nh.dtsi
@@ -178,7 +178,6 @@
 
 		gpio-sda = <&gpio 19 GPIO_ACTIVE_HIGH>;
 		gpio-sck = <&gpio 20 GPIO_ACTIVE_HIGH>;
-		mii-bus = <&mdio0>;
 
 		mdio-bus {
 			status = "okay";