c79d266e62
If the rules to tag specific USB interface numbers only apply on the PID, we'll
end up seeing that if the port has a parent with another PID, and that other
PID also has a rule, port will get tagged multiple times. Easier to see with an
example:
The ZTE MF637 (VID 0x19D2, PID 0x0121) had the following rules:
ATTRS{idProduct}=="0121", ENV{.MM_USBIFNUM}=="04", ENV{ID_MM_ZTE_PORT_TYPE_MODEM}="1"
ATTRS{idProduct}=="0121", ENV{.MM_USBIFNUM}=="01", ENV{ID_MM_ZTE_PORT_TYPE_AUX}="1"
In our ZTE rules we also have some for the device with PID 0x0002, like:
ATTRS{idProduct}=="0002", ENV{.MM_USBIFNUM}=="02", ENV{ID_MM_ZTE_PORT_TYPE_MODEM}="1"
ATTRS{idProduct}=="0002", ENV{.MM_USBIFNUM}=="04", ENV{ID_MM_ZTE_PORT_TYPE_AUX}="1"
And it seems that we can grab multiple PIDs from a single port, i.e. from the
parent objects in the hierarchy:
udevadm info -a -n /dev/ttyUSB4 | grep idProduct
ATTRS{idProduct}=="0121"
ATTRS{idProduct}=="0020"
ATTRS{idProduct}=="0002"
Where that 0x0002 idProduct is not from the modem, but from the EHCI Host
Controller (with idVendor 0x1d6b in my case).
So... we end up seeing that both set of rules will apply to the ports, and we
misleadingly get:
(ttyUSB3) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
ZTE: AT port 'tty/ttyUSB2' flagged as primary
(ttyUSB2) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
ZTE: AT port 'tty/ttyUSB1' flagged as secondary
(ttyUSB1) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
ZTE: AT port 'tty/ttyUSB4' flagged as primary
b_port(): (ttyUSB4) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB2 at (primary)
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB1 at (secondary)
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB2 data (primary)
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB0 qcdm
Which is wrong, as ttyUSB4 should have been our primary port, not ttyUSB2.
With this patch on, the rules apply only to the VID/PID pair, and we end up
getting what we really wanted:
(ttyUSB3) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
(ttyUSB2) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
ZTE: AT port 'tty/ttyUSB1' flagged as secondary
(ttyUSB1) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
ZTE: AT port 'tty/ttyUSB4' flagged as primary
b_port(): (ttyUSB4) type 'at' claimed by /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB4 at (primary)
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB1 at (secondary)
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB4 data (primary)
(/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2) tty/ttyUSB0 qcdm
https://bugzilla.gnome.org/show_bug.cgi?id=694759
ModemManager. The problem ModemManager tries to solve is to provide a unified high level API for communicating with (mobile broadband) modems. While the basic commands are standardized, the more advanced operations (like signal quality monitoring while connected) varies a lot. Using. ModemManager is a system daemon and is not meant to be used directly from the command line. However, since it provides DBus API, it is possible to use 'dbus-send' command to control it from the terminal. There's an example program (tests/mm-test.py) that demonstrates the basic API usage. Implementation. ModemManager is a DBus system bus activated service (meaning it's started automatically when a request arrives). It is written in C. The devices are queried from udev and automatically updated based on hardware events. There's a GInterface (MMModem) that defines the modem interface and any device specific implementation must implement it. There are two generic MMModem implementations to support the basic operations (one for GSM, one for CDMA,) which are common for all cards. Plugins. Plugins are loaded on startup, and must implement the MMPlugin interface. It consists of a couple of methods which tell the daemon whether the plugin supports a port and to create custom MMModem implementations. It most likely makes sense to derive custom modem implementations from one of the generic classes and just add (or override) operations which are not standard. There's a fully working plugin in the plugins/ directory for Huawei cards that can be used as an example for writing new plugins. Writing new plugins is highly encouraged! API. The API is open for changes, so if you're writing a plugin and need to add or change some public method, feel free to suggest it!