netdev led trigger on wwan0 actived even the qmi has not been started

Username: Dirk Chang

Origin: https://bugs.openwrt.org/index.php?do=details&task_id=2472

Supply the following if possible:

• Device problem occurs on Orange PI One based board

• Software versions of OpenWrt/LEDE release, packages, etc.

• Steps to reproduce

This happens with Quectel EC25 LTE modem (USB interface, 2c7c:0125). The board is based on Allwinner H3, using openwrt-19.07-snapshot (kernel 4.14.140).

Following is the configuration, that 4g_wan will not be enabled when booted. But the LED binded with wwan0 been actived even the 4g_wan does not be enabled.

config interface '4g_wan' option proto 'qmi' option device '/dev/cdc-wdm0' option auto '0'

config led 'led_modem' option name 'modem' option sysfs 'kooiot:green:modem' option trigger 'netdev' option mode 'link tx rx' option default '0' option dev 'wwan0'

Once we enabled the 4g_wan, and then disabled the 4g_wan, the LED will be turned off.

When system booted, ifconfig -a shows:

wwan0 Link encap:Ethernet HWaddr AA:C8:51:F9:2A:67
BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

when 4g_wan enabled and disabled, ifconfig -a shows:

wwan0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
POINTOPOINT NOARP MULTICAST MTU:1500 Metric:1 RX packets:2 errors:0 dropped:0 overruns:0 frame:0 TX packets:8 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:636 (636.0 B) TX bytes:1192 (1.1 KiB)