PinePhone modem keeps "disappearing"

[zetabeta]

I am already using ATTR{power/control}="on" (since January 18, see zetabeta's snippet). It does not solve the issue. Often, the modem does not even come up on USB to begin with, so the udev rules will definitely have no effect, and even when it does, the udev rules do not prevent it from disappearing from USB. The modem is still running, mind you (as it can be talked to over ttyS2), just not on USB.

i forgot to tell that modification is practically needed for funtional state. modem has bad habit to disconnect every few hours and disappear every day with default settings.

can you get to the state where "lsusb" says "Bus ### Device ###: ID 05c6:9008 Qualcomm, Inc. Gobi Wireless Modem (QDL mode)". does it appear and disappear constantly?