dt-bindings: add documentation for slew rate

Add documentation for slew rate.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
index 470283b4ddbf57a9c796c647df9eb75d9056e229..eb39f5051159f3aa29c0ace536288b7e592dae05 100644 (file)
--- a/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
@@ -100,6 +100,7 @@ DRIVE_STRENGTH (3 << 5): indicate the drive strength of the pin using the
                                11 - High
 OUTPUT         (1 << 7): indicate this pin need to be configured as an output.
 OUTPUT_VAL     (1 << 8): output val (1 = high, 0 = low)
+SLEWRATE       (1 << 9): slew rate of the pin: 0 = disable, 1 = enable
 DEBOUNCE       (1 << 16): indicate this pin needs debounce.
 DEBOUNCE_VAL   (0x3fff << 17): debounce value.