gpio: document open drain/source behaviour
authorLinus Walleij <linus.walleij@linaro.org>
Tue, 5 Apr 2016 14:49:57 +0000 (16:49 +0200)
committerLinus Walleij <linus.walleij@linaro.org>
Sat, 9 Apr 2016 18:14:26 +0000 (20:14 +0200)
commit6b5029d3ec86ee9558a1ab0b4b41a98e970e2204
tree00722e622de49da9fa748f0d02762f74d47b3fb5
parenta0e637387a9858f9c2e8228bc15e299387dadcd1
gpio: document open drain/source behaviour

This has been a totally undocumented feature for years so add some
generic concepts and documentation about open drain/source, include
some facts on how we now support for hardware.

Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Documentation/gpio/driver.txt