I have some problems with power management in SL8090 and SL8082 using
linux drivers sierra.c and sierra_net.c (2.0 and 3.0) in direct-ip mode.
I want to ask about meaning of some defines in sierra_net.c modem driver.
#define SIERRA_NET_SYNCDELAY (2*HZ)
is used for timer and scheduling work which sends/receives some data
(kind of sync). Such timing will brake usb pm (autosuspend) because
autosuspend - too frequent communication disables suspend.
After increasing this time usb autosuspend is achieved but data
connection is unstable. Data connection is stopped (dead until modem reboot)
and sometimes the modem can reboot itself (or usb iface).
The same behaviour is when SIERRA_NET_SYNCDELAY is unchanged (2 HZ - seconds)
but autosuspend is set to 0 in kernel sysfs.
It seems that every pm cycle in usb can lead to some bogus behaviour, using
I have tested the modems witch ppp configuration (sierra.c is only used)
and it seems to work better.
I will be grateful for any help or opinion.