This moves the GPIO fan bindings to the hwmon bindings. The GPIO
fan is a hwmon class hardware, not related to GPIO other than being
a consumer of GPIOs.

Cc: devicetree@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Allow gpio-fan to be used as thermal cooling device for platforms that
use GPIO maps to control fans.

As part of this change, we make the shutdown and remove logic the same
as well.
Signed-off-by: NNishanth Menon <nm@ti.com>
Acked-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

On some boards, such as the LaCie 2Big Network v2 or 2Big NAS (based on
Marvell Kirkwood SoCs), an I2C fan controller is used but the alarm
signal is wired to a separate GPIO. Unfortunately, the gpio-fan driver
can't be used to handle GPIO alarm alone from DT: an error is returned
if the "gpios" DT property is missing.

This patch allows to use the gpio-fan driver even if the "alarm-gpios"
DT property is defined alone.
Signed-off-by: NSimon Guinot <simon.guinot@sequanux.org>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Allow a gpio-fan to be defined in devicetree, see binding documentation
for details.
Signed-off-by: NJamie Lentin <jm@lentin.co.uk>
Acked-by: NAndrew Lunn <andrew@lunn.ch>
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>