[PATCH 0/4] gpio: driver for the RPi3 GPIO expander

Hi Baruch,

Baruch Siach [off-list ref] hat am 2. Januar 2018 um 14:19 geschrieben:


The Raspberry Pi 3 has a GPIO expander that controls, among others, the 
activity LED, and the camera connector GPIOs. The GPIO expander on an I2C bus 
that is not directly controlled from the ARM core. The VC4 firmware controls 
the I2C bus, and allows the ARM core to set/get GPIO settings over its mailbox 
interface.

This series adds support for the RPi3 expander.

The driver is ported from the downstream kernel at 
https://github.com/raspberrypi/linux/, branch rpi-4.9.y.

thanks for trying to upstream this. There has been attemps by Eric Anholt (September 2016) and Michael Zoran (March 2017). Some problems like get_direction() has been fixed, but not all of them.

So please look at the followings links first:
https://patchwork.kernel.org/patch/9339859/
https://patchwork.kernel.org/patch/9339857/
http://lists.infradead.org/pipermail/linux-rpi-kernel/2017-March/005903.html

Stefan