Hello,

I'm using the modem Telit HE910 with cdc-acm driver.

I've found that after a suspend and resume of the operating system
(e.g. pm-suspend), the modem does not answer anymore.

Collecting logs with an usb sniffer, it seems that, unlike the Windows
driver, the host does not send the packet SET_FEATURE DEVICE_REMOTE
WAKEUP, needed by the modem.

I've added few lines of code (in the acm_suspend function) for sending
this packet and now things work.

According to the USB 2.0 specs it seems to me that this feature should
be always requested when suspending a device, so probably the driver
behavior is not correct.

Does cdc-acm really not support this feature or am I missing some
configuration parameters that enable the sending of this request?

Thanks,
Daniele
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to