Firmware update allows the various firmware images to be updated from the application processor. This includes the modem bootloader, modem firmware, and linux image, where the linux image consists of the linux bootloader, linux kernel, and linux rootfs.

Firmware update is useful when the image comes from an alternative source, rather than as an over-the-air update through the AirVantage service.

Update Firmware Image

The firmware update process is started by calling le_fwupdate_Download(). This function takes a file descriptor, rather than a file, to provide flexibility in the source of the image. In particular, this can be used to stream the image, rather than having to save it on the file system before doing the update.

If the image is successfully downloaded to the modem, the modem will reset in order to apply the update. This will reset both the modem and application processors. After the application processor has restarted, the le_fwupdate_version APIs can be used to determine whether the firmware has been updated to the new version.