fwupd/plugins/fastboot/README.md
Richard Hughes 078beafb2d Add a new internal flag to opt-in to GUID matching
It is far too easy to forget to set FWUPD_DEVICE_FLAG_NO_GUID_MATCHING for new
plugins, and without it it all works really well *until* a user has two devices
of the same type installed at the same time and then one 'disappears' for hard
to explain reasons. Typically we only need it for replug anyway!

Explicitly opt-in to this rarely-required behaviour, with the default to just
use the physical and logical IDs. Also document the update behavior for each
plugin to explain why the flag is being used.

This allows you to have two identical Unifying plugged in without one of them
being hidden from the user, at the same time allowing a HIDRAW<->USB transition
when going to and from bootloader and runtime modes.

This removes the workaround added in 99eb3f06b6.

Fixes https://github.com/fwupd/fwupd/issues/2915
2021-02-25 15:47:25 +00:00

1.8 KiB

Fastboot Support

Introduction

This plugin is used to update hardware that uses the fastboot protocol.

Firmware Format

The daemon will decompress the cabinet archive and extract a firmware blob in ZIP file format. Inside the zip file must be all the firmware images for each partition and a manifest file. The partition images can be in any format, but the manifest must be either an Android flashfile.xml format file, or a QFIL partition_nand.xml format file.

For both types, all partitions with a defined image found in the zip file will be updated.

This plugin supports the following protocol ID:

  • com.google.fastboot

GUID Generation

These devices use the standard USB DeviceInstanceId values, e.g.

  • USB\VID_18D1&PID_4EE0&REV_0001
  • USB\VID_18D1&PID_4EE0
  • USB\VID_18D1

Update Behavior

A fastboot device usually presents in runtime mode (or with no interface), but if the user puts the device into fastboot mode using a physical button it then enumerates with a USB descriptor. On attach the device reboots to runtime mode which may mean the device "goes away".

For this reason the REPLUG_MATCH_GUID internal device flag is used so that the bootloader and runtime modes are treated as the same device.

Quirk use

This plugin uses the following plugin-specific quirk:

Quirk Description Minimum fwupd version
FastbootBlockSize Block size to use for transfers 1.2.2

Vendor ID Security

The vendor ID is set from the USB vendor, for example USB:0x18D1

External interface access

This plugin requires read/write access to /dev/bus/usb.