Messages in this thread | | | From | Eric Anholt <> | Subject | Re: [PATCH 27/32] gpio: Add support for the FXL6408 GPIO expander. | Date | Mon, 06 Jun 2016 16:50:31 -0700 |
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Gerd Hoffmann <kraxel@redhat.com> writes:
> From: Eric Anholt <eric@anholt.net> > > This commit needs to be split up and cleaned up. Also we should add > interrupt support before pushing upstream. > > Signed-off-by: Eric Anholt <eric@anholt.net>
OK, I've confirmed with the firmware maintainers: We really can't drive this natively from Linux. The firmware is polling one of the fxl6408's pins 10 times a second for detecting under-voltage, so if we also try to drive it we'll end up smashing each others' I2C transactions. We'll need to do a GPIO driver using the GET/SET_GPIO_STATE firmware calls, instead. Unfortunately, we don't have a direction-setting API for that at the moment, but it'll at least let us read the HDMI HPD signal. [unhandled content-type:application/pgp-signature] | |