Sierra Wireless Legato

In the last years, the modem manufacturer Sierra Wireless has started to create modem modules for M2M/IoT applications based on the Qualcomm chipsets with embedded Linux. As opposed to other manufacturers, they are aggressively marketing the running of user-specific application code on the Linux-running ARM core.

However, rather than giving users access to the real interfaces of those modules (e.g. Qualcomm QMI), they create their own walled garden called Legato. This Legato framework is not fully open source. As a result, if you write software within that framework, it means that there is vendor lock-in and the resulting programs are not portable and will not run on other modems.

This is quite sad, but unfortunately this policy wastes almost all the potential of those products. Writing application programs as regular Linux programs is done exactly because they are portable from small to large devices of any vendor.

Nevertheless, the Modem modules of course provide the option to remove the Legato proprietary bits and run native Linux programs, just like any other Linux based modem.

Having said that, they do publish all their OE recipes for you to re-build the filesytem images and seem to actively encourage their users to do so (e.g. in order to build customized images with their own software). This is definitely a big step ahead of other vendors.

Products with Linux and Legato:

It seems like all the WP Series Devices run Qualcomm based modem chips with built-in Linux.

  • WP8548
  • WP7603
  • WP7601
  • WP7504-1
  • WP7504
  • WP7502
  • WP7601-1
  • WP7603-1

Legato yocto / OpenEmbedded

Unfortunately Sierra Wireless does not publish their OE recipes / meta layers in git. This is sad twice, as they keep other parts of their Legato in git at You can download their yocto from

In any case, information on building/using their Yocto port is available from

Updated by laforge almost 7 years ago · 4 revisions

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