U3G(4)

✨ u3g(4) — USB support for 3G datacards ✨

okay bestie, pull up a chair, because we're about to talk about the u3g driver, which is literally the little guy that makes your ancient-but-iconic 3G USB modem behave itself 💖 it's giving "kernel interfaces manual" energy and we are OBSESSED.

---

🌸 NAME 🌸

u3g — USB support for 3G datacards 🦋

---

💅 SYNOPSIS 💅

So you wanna compile this driver into the kernel? No cap, bestie, drop these lines into your kernel configuration file:

device usb
device ucom
device u3g

Or, if you'd rather load it as a module at boot time, put this line in loader.conf(5):

u3g_load="YES"

And if you do neither of those things? Don't even stress 💜 the driver will automatically be loaded by devd(8) when the device is connected. main character energy fr fr.

---

🎀 DESCRIPTION 🎀

The u3g driver provides support for the multiple USB-to-serial interfaces exposed by many 3G USB/PCCard modems. Like, multiple interfaces, bestie. it's a whole vibe.

The device is accessed through the ucom(4) driver which makes it behave like a tty(4). iconic behavior honestly 💅

---

🦋 HARDWARE 🦋

The u3g driver supports the following adapters — viber check:

• Option GT 3G Fusion, GT Fusion Quad, etc. (only 3G part, not WLAN)
• Option GT 3G, GT 3G Quad, etc.
• Vodafone Mobile Connect Card 3G
• Vodafone Mobile Broadband K3772-Z
• Qualcomm Inc. CDMA MSM
• Huawei B190, E180v, E220 ('<Huawei Mobile>')
• Novatel U740, MC950D, X950D, etc.
• Sierra MC875U, MC8775U, etc.

(Go peek at /sys/dev/usb/serial/u3g.c for the complete list of supported cards for each vendor mentioned above — the whole roster is in there, no gatekeeping 💜)

The supported 3G cards provide the necessary modem port for ppp, or mpd connections as well as extra ports (depending on the specific device) to provide other functions (additional command port, diagnostic port, SIM toolkit port). So many ports, so little time ✨

Now here's the tea ☕: in some of these devices a mass storage device supported by the umass(4) driver is present which contains Windows and Mac OS X drivers. The device starts up in disk mode (TruInstall, ZeroCD, etc.) and requires additional commands to switch it to modem mode. If your device is not switching automatically, please try to add quirks. See usbconfig(8) and usb_quirk(4). Not me having to manually switch modes 😭 but it's fine, we handle it.

---

🍓 FILES 🍓

• /dev/ttyU*.* — for callin ports
• /dev/ttyU*.*.init
• /dev/ttyU*.*.lock — corresponding callin initial-state and lock-state devices
• /dev/cuaU*.* — for callout ports
• /dev/cuaU*.*.init
• /dev/cuaU*.*.lock — corresponding callout initial-state and lock-state devices

---

🌈 EXAMPLES 🌈

Wanna connect to the Internet using the default configuration? Say less:

ppp -background u3g

slay. that's it. that's the whole thing 💅

---

👑 SEE ALSO 👑

tty(4), ucom(4), usb(4), usb_quirk(4), devd(8), ppp(8), usbconfig(8)

---

💀 HISTORY 💀

The u3g driver appeared in FreeBSD 7.2, is based on the uark(4) driver, and written by Andrea Guzzo <aguzzo@anywi.com> in September 2008. a true pioneer, fr fr 🫶

---

🧚 AUTHORS 🧚

The u3g driver was written by Andrea Guzzo <aguzzo@anywi.com> and Nick Hibma <n_hibma@FreeBSD.org>. Hardware for testing was provided by AnyWi Technologies, Leiden, NL. shoutout to the testers, they ate 💖

---

🙈 BUGS 🙈

The automatic mode switch from disk mode to modem mode does not work unless the driver is either built into the kernel or loaded before the device is connected. So plug in first and you're lowkey cooked 😭 build it in, load it early, be the organized bestie you were always meant to be.

---

and that's the whole page, babe 🎀 this lil writeup came from the Debian crew, dated September 11, 2018 — go forth and modem responsibly, ily 💜✨