Commit c477ebe2 authored May 06, 2017 by Ulf Hansson

mmc: dt: pwrseq-simple: Invent power-off-delay-us



During power off, after the GPIO pin has been asserted, some devices like
the Wifi chip from TI, Wl18xx, needs a delay before the host continues with
clock gating and turning off regulators as to follow a graceful shutdown
sequence.

Therefore invent an optional power-off-delay-us DT binding for
mmc-pwrseq-simple, to allow us to support this constraint.

Cc: devicetree@vger.kernel.org
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mmc@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>

parent 08332893

Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt

+2 −0

Original line number	Diff line number	Diff line
		@@ -18,6 +18,8 @@ Optional properties:
		"ext_clock" (External clock provided to the card).
		- post-power-on-delay-ms : Delay in ms after powering the card and
		de-asserting the reset-gpios (if any)
		- power-off-delay-us : Delay in us after asserting the reset-gpios (if any)
		during power off of the card.

		Example: