[PATCH v2 0/3] sunxi: add "fake" FEL button feature

[Andre Przywara <andre.przywara@arm.com>]

Some boards with Allwinner SoCs feature a "FEL" key, sometimes also
labelled "uboot", which allows to easily enter the BootROM FEL mode, when
pressed upon power-on or reset. This allows to access the USB-OTG boot
protocol, for convenient access to memory and uploading code.

Add a software emulation of this functionality for boards without a button
connected to this special SoC pin, to give easy FEL access to more
boards. Any GPIO can be used, as long as the button uses active-low
logic.

This is used on the X96 Mate TV box, where the hidden "update" button is
actually just some GPIO, checked by the vendor firmware.

Please have a look!

Cheers,
Andre

Changelog v1 .. v2:
- add patch to fix return_to_fel() prototype
- document signal needs to be active-low
- activate internal pull-up resistors
- add patch to activate button on the X96 Mate TV box

Andre Przywara (3):
  sunxi: fix return_to_fel() prototype
  sunxi: add "fake" FEL pin support
  sunxi: x96_mate: Add "fake" FEL key definition

 arch/arm/include/asm/arch-sunxi/sys_proto.h |  4 +--
 arch/arm/mach-sunxi/Kconfig                 | 10 +++++++
 arch/arm/mach-sunxi/board.c                 | 31 +++++++++++++++++++++
 configs/x96_mate_defconfig                  |  1 +
 4 files changed, 44 insertions(+), 2 deletions(-)

-- 
2.46.3