Qualcomm MSM Interface

The Qualcomm MSM Interface is a proprietary interface for interacting with Qualcomm baseband processors and is a replacement for the legacy cellular extensions of the Hayes command set.^[1] With mobile chipsets, communication between the application processor and the baseband processor happens through shared memory. On PCs with data cards, QMI is exposed through USB.^[2][3]

Linux

In the Linux kernel, QMI can be used through two mutually exclusive drivers: GobiNet and qmi_wwan. These two drivers take completely different approaches to handle the protocol. GobiNet is a complex proprietary driver which implements within the kernel most of the core protocol logic, while qmi_wwan is part of the upstream kernel and leaves all those tasks to user-space processes, and therefore keeping the kernel driver as small as possible.^[1][4] There are several userspace implementations, such as uqmi on OpenWrt,^[5] oFono^[6] and libqmi^[7]

See also

• Radio Interface Layer
• QMI - postmarketOS Wiki