Anyone testing an MC7430 or other MDM9x30 based modem

[Aleksander Morgado]

On Thu, Dec 3, 2015 at 2:39 PM, Bjørn Mork <bjorn at mork.no> wrote:
>
> We might have painted ourselves into a corner here. OK, *I* have painted
> myself into the corner :) . Delegating the QMI client allocation to
> userspace means that the driver does not know when its OK for the
> firmware to release all resources.  Both netdev and cdc-wdm being closed
> is not enough.  There can still be a userspace process holding a client
> ID, assuming it can be used to talk to the firmware again.  That means
> that we cannot ever clear "needs_remote_wakeup" on the MDM9x30.
>
> What do we do about that?  Oh, I wish I had required the cdc-wdm device
> being held open whenever you have a valid client ID.  Can we change that
> now?  I guess not.  Any other way out of this?

This issue would likely only affect qmicli without proxy usage. As
soon as the qmi-proxy is used the cdc-wdm device should be kept open
as long as there are clients registered (i.e. even with a sequence of
qmicli calls re-using the same id). ModemManager (uses qmi-proxy as
well), uqmi and ofono will all keep the port open as well if I'm not
mistaken. So I'd say it may not be that big of an issue, if the
needs_remote_wakeup stuff is mandatory in the driver; we can always
just require the qmi-proxy when qmicli is being used. Not saying we
should do it, just saying that we always have that option if there's
no other way to do it :)

-- 
Aleksander
https://aleksander.es