We use the Icon ID here because a value of 1 *always* means not roaming,
while the other values don't appear to be consistent. For example,
an ERI value of "0" is supposed to mean roaming according to the
standards, but the Novatel devices appear to use 0 to mean home.
Since we're not sure, don't depend on the ERI value itself, just
depend on the Icon ID, where we know for sure that 1 means "home".
$NWQMISTATUS sometimes returns 'ERROR'. This patch modifies the Novatel
LTE plugin to retry $NWQMISTATUS (up to 5 times) to determine if the
disconnect operation succeeds. It also changes the plugin to assume that
the disconnect operation succeeds if $NWQMISTATUS fails to report the
current connection status.
Soft resetting a Novatel LTE modem can a significant amount of time
(3-4 seconds). If the modem is newly plugged in, skip the unnecessary
soft reset when enabling the modem.
We don't want to retry DHCP? on every possible GError reported; specially if the
error is about the port being forced to get closed when the modem gets
unplugged or the like. So just retry on very specific errors reported.
The main cause for retry is really when the modem replies the following:
--> AT^DHCP?
<-- ERROR
Which in our case gets translated to a 'unknown' mobile equipment error. We'll
also consider any kind of mobile equipment error, as the modems may reply a
CME ERROR instead.
We will now use a step-based state machine to handle the connection and
disconnection sequences. All the previous behaviour is kept, except for these
new things:
* Instead of just subclassing the 'dialling' step in the 3GPP connection
sequence, completely subclass the whole 3GPP connection sequence. We do this
because we don't need to preconfigure PDP contexts with AT+CGDCONT before
issuing ^NDISDUP.
* Don't allow IP types other than IPv4. These modems work only with IPv4
bearers.
* Remove cancellation signal handler; not needed as we can check the status of
the cancellation in every 1s timeout.
* Removed the event source id handling for timeouts; timeouts are never
cancelled here.
Modems with ECM (e.g. usb0) ports should use AT^NDISDUP in the control port to
request the connection and afterwards just fire up the DHCP client in the net
port.
This patch is originally developed by:
Franko Fang <fangxiaozhi@huawei.com>
And afterwareds reviewed and updated by:
Aleksander Morgado <aleksander@gnu.org>
Sierra CDMA devices don't always have QCDM ports, or if they do,
they aren't always usable. Try Sierra-proprietary commands for
loading the modem's MDN and fall back to QCDM if that fails.
mm_get_int_from_str() does not allow anything in the string after the
number, eg "-91 asdfasdf" returns an error. So we have to chop off
anything after the number we're interested in.
When both load_power_state() and modem_power_down() are not implemented, the
logic will launch the power-up command during (only the first) enabling of the
modem.
In this kind of modems, CFUN is directly related to allowed/preferred modes, so
during the initial power-up we'll just assume we want ANY mode.
This logic is now implemented by the parent broadband modem object.
Also, implement a custom initial power state loading, so that CDMA-only modems
get marked as 'offline', in order to launch !pcstate=1 to power them up during
the first enabling. The custom initial power state loading will run the parent's
implementation in non-CDMA-only modems.
Specially the first time that CFUN=1,0 is issued after the initial power up, we
really need to wait more than 3s for the AT command reply. Otherwise, the modem
won't like it and it will reset itself :-/
Plain non-Icera ZTE modems will use ATD calls and PPP to establish the
connection, so ignore 'net' ports that may be found in the way (e.g. when the
modem is a QMI modem and we're not using QMI support).
Unfortunately, Sierra secondary APP ports reply to +GCAP with
only "OK", and not their APP port number or model number. So instead
of using +GCAP, we have to use ATI to get secondary port information.
This allows us to detect which port is the APP1 port that we can
potentially use for PPP, leaving the primary port available for
control and status.
Also, some modems have up to 3 or 4 APP secondary ports, which we
need to ensure aren't used as primary. The previous check for +GCAP
handled that, but let's make it more explicit.
AT+GCAP reply:
OK
ATI reply:
Sierra Wireless, Inc.
C885
APP1
OK
See also: 3f3987e09ee762e48c1d53cb42a1288ce9f332cb (MM_06)
If the primary port is gone (e.g. when going to sleep) and we are just in the
middle of a connection attempt, we won't be able to receive any unsolicited
message regarding the status of the attempt. So, if we detect that the port is
forced to get closed, we'll just treat it as a connection failure.
http://code.google.com/p/chromium-os/issues/detail?id=35391
Turns out older devices (like the C885/AT&T Mercury) crash often
when we don't wait for them to settle from CFUN=1. 5 seconds is
too short, but the crashes go away when we wait for 10 seconds.
Newer modems like the USB306 don't have this problem, so we just
check to see if the modem is a DirectIP device (using sierra_net)
and only use the shorter timeout for those newer devices.
This is a separate problem from some older modems returning ERROR
to valid commands that are sent too soon after CFUN=1, which was
observed on really old devices like the PCMCIA 860.
Many Huawei CDMA modems implement vendor commands for 1x and EVDO
signal quality, so use them since they are more accurate than the
generic signal checking.
(port of a similar patch for MM_06 by heiher <admin@heiher.info>)
Dan Williams
Ben Chan
Aleksander Morgado
Franko Fang