[PATCH 1/8] mmc: dt: pwrseq-simple: Invent power-off-delay-us

Ulf Hansson ulf.hansson at linaro.org
Mon May 8 09:21:10 PDT 2017


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 at vger.kernel.org
Cc: Rob Herring <robh+dt at kernel.org>
Cc: linux-mmc at vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
---
 Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt b/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt
index e254368..9029b45 100644
--- a/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt
@@ -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:
 
-- 
2.7.4




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