[Android Q&A, Help & Troubleshooting] melvaka:
Lenovo A10-70F KitKat 4.4.4 Stock ROM build A10-70F_S000021_150501_ROW

multi-user mod in build.prop

TWRP2870 recovery

SuperSU

Terminal Emulator as root

This uses a MediaTek MT6620 for Wi-Fi, Bluetooth, GPS & FM

All these functions have stopped working. Attempting to turn on the wi-fi in settings

gives

adb logcat wpa_supplicant:V *:S

D/wpa_supplicant(23240): wpa_supplicant v2.1-devel-4.4.4
D/wpa_supplicant(23240): Add randomness: count=1 entropy=0
D/wpa_supplicant(23240): random pool - hexdump(len=128): [REMOVED]
D/wpa_supplicant(23240): random_mix_pool - hexdump(len=8): [REMOVED]
D/wpa_supplicant(23240): random_mix_pool - hexdump(len=20): [REMOVED]
D/wpa_supplicant(23240): random pool - hexdump(len=128): [REMOVED]
D/wpa_supplicant(23240): random: Added entropy from /data/misc/wifi/entropy.bin
(own_pool_ready=2)
D/wpa_supplicant(23240): random: Trying to read entropy from /dev/random
D/wpa_supplicant(23240): Get randomness: len=20 entropy=1
D/wpa_supplicant(23240): random from os_get_random - hexdump(len=20): [REMOVED]
D/wpa_supplicant(23240): random_mix_pool - hexdump(len=20): [REMOVED]
D/wpa_supplicant(23240): random from internal pool - hexdump(len=16): [REMOVED]
D/wpa_supplicant(23240): random_mix_pool - hexdump(len=20): [REMOVED]
D/wpa_supplicant(23240): random from internal pool - hexdump(len=16): [REMOVED]
D/wpa_supplicant(23240): mixed random - hexdump(len=20): [REMOVED]
D/wpa_supplicant(23240): random: Updated entropy file /data/misc/wifi/entropy.bi
n (own_pool_ready=2)
D/wpa_supplicant(23240): Global control interface '@android:wpa_wlan0'
D/wpa_supplicant(23240): Using Android control socket 'wpa_wlan0'
I/wpa_supplicant(23240): Successfully initialized wpa_supplicant
D/wpa_supplicant(23240): Override interface parameter: ctrl_interface ('(null)'
-> '/data/misc/wifi/sockets')
D/wpa_supplicant(23240): Initializing interface 'wlan0' conf '/data/misc/wifi/wp
a_supplicant.conf' driver 'nl80211' ctrl_interface '/data/misc/wifi/sockets' bri
dge 'N/A'
D/wpa_supplicant(23240): Configuration file '/data/misc/wifi/wpa_supplicant.conf
' -> '/data/misc/wifi/wpa_supplicant.conf'
D/wpa_supplicant(23240): Reading configuration file '/data/misc/wifi/wpa_supplic
ant.conf'
D/wpa_supplicant(23240): ctrl_interface='wlan0'
D/wpa_supplicant(23240): update_config=1
D/wpa_supplicant(23240): manufacturer='MediaTek Inc.'
D/wpa_supplicant(23240): device_name='Wireless Client'
D/wpa_supplicant(23240): model_name='MTK Wireless Model'
D/wpa_supplicant(23240): model_number='1.0'
D/wpa_supplicant(23240): serial_number='2.0'
D/wpa_supplicant(23240): os_version=01020300
D/wpa_supplicant(23240): config_methods='display push_button keypad'
D/wpa_supplicant(23240): p2p_no_group_iface=1
D/wpa_supplicant(23240): driver_param='use_p2p_group_interface=1'
D/wpa_supplicant(23240): Reading configuration file '/system/etc/wifi/wpa_suppli
cant_overlay.conf'
D/wpa_supplicant(23240): p2p_no_group_iface=1
D/wpa_supplicant(23240): driver_param='use_p2p_group_interface=1'
I/wpa_supplicant(23240): rfkill: Cannot open RFKILL control device
D/wpa_supplicant(23240): nl80211: RFKILL status not available
D/wpa_supplicant(23240): interface wlan0 doesn't exist, wait 1s to retry
D/wpa_supplicant(23240): interface wlan0 doesn't exist, wait 1s to retry
D/wpa_supplicant(23240): interface wlan0 doesn't exist, wait 1s to retry
D/wpa_supplicant(23240): interface wlan0 doesn't exist, wait 1s to retry
I/wpa_supplicant(23240): nl80211: Driver does not support authentication/associa
tion or connect commands
D/wpa_supplicant(23240): netlink: Operstate: linkmode=0, operstate=6
E/wpa_supplicant(23240): Could not read interface wlan0 flags: No such device
D/wpa_supplicant(23240): set wowlan for if wlan0, index 0
D/wpa_supplicant(23240): nl80211: set_wowlan failed; err=-19 No such device)
D/wpa_supplicant(23240): nl80211: Set mode ifindex 0 iftype 2 (STATION)
D/wpa_supplicant(23240): nl80211: Failed to set interface 0 to mode 2: -19 (No s
uch device)
E/wpa_supplicant(23240): wlan0: Failed to initialize driver interface
D/wpa_supplicant(23240): Failed to add interface wlan0

there is no rfkill entry in /sys/class

An unfiltered adb logcat spews this repeatedly

D/agps ( 197): [agps] WARNING: [CP] cp2_fd_1_reconnect_timeout
E/agps ( 197): [agps] ERR: [CP] get_ccci_uart open failed node=[/dev/ttyC2]
reason=[No such file or directory]
E/agps ( 197): [agps] ERR: [CP] get_eemcs_uart open failed node=[/dev/eemcs
_ipc_uart] reason=[No such file or directory]
E/agps ( 197): [agps] ERR: [CP] ccci_uart_1 open failed
I/6620_launcher( 184): Can't open device node(/dev/stpwmt)
I/6620_launcher( 184): Can't open device node(/dev/stpwmt)
I/6620_launcher( 184): Can't open device node(/dev/stpwmt)
I/6620_launcher( 184): Can't open device node(/dev/stpwmt)
I/6620_launcher( 184): Can't open device node(/dev/stpwmt)
I/6620_launcher( 184): Can't open device node(/dev/stpwmt)
I/6620_launcher( 184): Can't open device node(/dev/stpwmt)

however, the expected mt6620 devices are present in /dev, e.g.

crw-rw---- system system 190, 0 2010-01-02 01:01 stpwmt

Any known fixes, or is MT6620 chip dead ?

Unhappy 7-year-old :crying:

Tab wasn't rooted when wi-fi stopped working - I have only rooted it as part of diagnostics today