[PATCH v2 1/6] dt-bindings: rockchip-dw-mshc: add description of rockchip,power-invert

[Shawn Lin <shawn.lin@rock-chips.com>]

rockchip,power-invert is used for rockchip to introduce the flag
DW_MMC_CARD_PWR_INVERT from DT which should make the power control
of dw_mmc more flexible according to different hw design.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>

---

Changes in v2: None

 Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt
index 07184e8..5640659 100644
--- a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt
+++ b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt
@@ -30,6 +30,12 @@ Optional Properties:
   probing, low speeds or in case where all phases work at tuning time.
   If not specified 0 deg will be used.
 
+* rockchip,power-invert: Invert the power control of PWREN register. If adding
+  it, the card should be in power-on state when the power io outputs high level
+  voltage, and it should be in power-off state when outputing low level voltage.
+  otherwise the behaviour of power control should be the opposite way which is
+  the default policy of dw mshc.
+
 Example:
 
 	rkdwmmc0@12200000 {
-- 
2.3.7