This manual page documents briefly the dfu-tool command.
dfu-tool allows a user to write various kinds of firmware onto devices supporting the USB Device Firmware Upgrade protocol. This tool can be used to switch the device from the normal runtime mode to `DFU mode' which allows the user to read and write firmware. Either the whole device can be written in one operation, or individual `targets' can be specified with the alternative name or number.
All synchronous actions can be safely cancelled and on failure will return errors with both a type and a full textual description. libdfu supports DFU 1.0, DFU 1.1 and the ST DfuSe vendor extension, and handles many device `quirks' necessary for the real-world implementations of DFU.
Additionally dfu-tool can be used to convert firmware from various different formats, or to modify details about the elements, images and metadata contained inside the firmware file. For example, you can easily convert DFU 1.1 firmware into the vendor-specific DfuSe format, convert a Intel HEX file into a raw file padded to a specific size, or add new copyright and licensing information to an existing file. Fields such as the vendor and product IDs can be changed, and the firmware elements can be encrypted and decrypted using various different methods. Merging two DfuSe files together is also possible, although specifying different alt-setting numbers before merging is a good idea to avoid confusion.
Although dfu-tool tries to provide a large number of easy-to-use commands, it may only be possible to do certain operations using the libdfu library directly. This is easier than it sounds, as the library is built with GObject Introspection support making it usable in many languages such as C, Javascript and Python. Furthermore, using the library is a good idea if you want to perform multiple operations on large firmware files, for instance, converting from an Intel HEX file, padding to a certain size, setting vendor and adding licensing information and then saving to a remote location.
Failed to load quirks: Error creating directory /var/cache/fwupd: Permission denied