mmc: dt: pwrseq-simple: Invent power-off-delay-us
authorUlf Hansson <ulf.hansson@linaro.org>
Sat, 6 May 2017 09:41:30 +0000 (11:41 +0200)
committerUlf Hansson <ulf.hansson@linaro.org>
Tue, 23 May 2017 12:17:10 +0000 (14:17 +0200)
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>
Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt

index e25436861867f28f75a2450ecbf28d1fd2df3921..9029b45b8a22a8d5b6a1afa3184bf389a85202f4 100644 (file)
@@ -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: