Several plugins define the specific device vid:pid pairs they
support. Let's use this information as a direct indication that
ModemManager can probe the devices.
Several plugins define specific udev tags that must be available in
the device in order for the plugins to use them. Let's use these tags
as a direct indication that ModemManager can probe the devices.
In particular, this change would make all Ericsson MBM modems probed
right away also in STRICT filter mode, without needing to check the
ttyACM interface type or the available net ports.
This tag is completely redundant because users can whitelist the
platform TTY ports to use with the more generic ID_MM_DEVICE_PROCESS
tag, which is part of the explicit whitelist filter rule.
The udev tag that allows flagging devices that MAY be modems
(e.g. USB<->RS232 adapters) is only applicable to TTY devices, so
explicitly specify that in the tag name as well.
Until now the ID_MM_DEVICE_IGNORE udev tag was being used in the
internal blacklist of devices shipped by ModemManager when running in
either DEFAULT or PARANOID filter modes. The name of the tag is
extremely misleading because it doesn't really make the full device be
ignored, the tag only applied to TTY ports.
This commit repurposes the tag so that it applies to ANY kind of
port (e.g. TTY, NET, cdc-wdm...) and also to any kind of filter type
(i.e. also applicable in STRICT mode).
The internal blacklist shipped by ModemManager, which should NOT be
used in STRICT mode, uses a new tag name, ID_MM_TTY_BLACKLIST.
The new ID_MM_DEVICE_IGNORE tag is therefore much more usable and its
name is really meaningful. If there are users or third-party projects
adding their own udev rules with the ID_MM_DEVICE_IGNORE tag name,
they should have no problem as the new rule is more restrictive than
the old one.
This prevents errors due to nasty typos in the strings.
We define all symbols in a single header file that is NOT considered
part of the API, as there is no need for MM clients to know about
these tags code-wise. These tags are only meaningful when associated
to devices in udev.
Information of each tag is included in the general API documentation.
https://gitlab.freedesktop.org/mobile-broadband/ModemManager/issues/88
Do not automatically probe serial ports under the 'pci' or 'sdio'
platform drivers unless explicitly tagged with
ID_MM_PLATFORM_DRIVER_PROBE.
$ realpath /sys/class/tty/ttyS0/
/sys/devices/pci0000:00/0000:00:16.3/tty/ttyS0
$ basename $(realpath /sys/devices/pci0000:00/0000:00:16.3/subsystem)
pci
nozomi and qcaux only drive modems and thus should be included
in this filter rule. Allows nozomi/qcaux devices to work
automatically with strict filter mode.
All the previous filter rules were applicable per-port independently.
But, we also want to apply rules on a port based on the existence of
other ports on the same device (e.g. allow TTY if the device also has
a NET port). In this case, we need to wait for all ports to appear and
then apply the additional rules.
We re-use the "min wait time" timeout in the plugin-manager for this
same purpose. This timeout is setup to wait for ports to appear before
starting the probing process (e.g. so that plugin filters like the
forbidden-drivers one work). The very same timeout can therefore be
used to check whether we start the probing or not based on additional
filter rules.
The 'default' filter policy was based on blacklisting as much as
possible and otherwise allow.
The new 'strict' filter policy will be based on whitelisting as much
as much as possible, using custom defined rules, and otherwise forbid
the ports.
The new 'paranoid' filter policy is equivalent to the 'strict' filter
after having applied the blacklist rules from the 'default' filter.
The user can tag modems (either full devices or ports independently)
to be explicitly probed by ModemManager, using the new
"ID_MM_DEVICE_PROCESS" udev tag, e.g.:
$ sudo vim /lib/udev/rules.d/78-mm-whitelist-internal-modem.rules
ACTION!="add|change|move", GOTO="mm_whitelist_internal_modem_end"
ATTRS{idVendor}=="1199", ATTRS{idProduct}=="a001", ENV{ID_MM_DEVICE_PROCESS}="1"
LABEL="mm_whitelist_internal_modem_end"
$ sudo udevadm control --reload
$ sudo udevadm trigger
This rule runs before any other filter rule.
This tag may be used e.g. by manufacturers building systems with
built-in modems that will always be available.
Distributions targeting support for multiple modem devices shouldn't
use this udev tag.
E.g. forcing a MBIM modem to run in AT-only mode:
# MM_FILTER_RULE_NET=0 \
MM_FILTER_RULE_CDC_WDM=0 \
/usr/sbin/ModemManager --debug
This is just for quick testing for now.
This new object allows configuring the filter rules applied to the
device ports. By default, for now, it implements the same rules as the
MMKernelDevice is_candidate() method, which is obsoleted.
Aleksander Morgado
Dan Williams