pinctrl: sun6i: add SPDIF to pin description.

Add the SPDIF mux functionality to the pinctrl for the Allwinner A31
SoC.
Signed-off-by: NMarcus Cooper <codekipper@gmail.com>
Acked-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/sunxi/pinctrl-sun6i-a31.c

@@ -896,10 +896,18 @@ static const struct sunxi_desc_pin sun6i_a31_pins[] = {
 		  SUNXI_FUNCTION(0x1, "gpio_out")),
 	SUNXI_PIN(SUNXI_PINCTRL_PIN(H, 27),
 		  SUNXI_FUNCTION(0x0, "gpio_in"),
-		  SUNXI_FUNCTION(0x1, "gpio_out")),
+		  SUNXI_FUNCTION(0x1, "gpio_out"),
+		/*
+		 * The SPDIF block is not referenced at all in the A31 user
+		 * manual. However it is described in the code leaked and the
+		 * configuration files supplied by vendors.
+		 */
+		  SUNXI_FUNCTION(0x3, "spdif")),        /* SPDIF IN */
 	SUNXI_PIN(SUNXI_PINCTRL_PIN(H, 28),
 		  SUNXI_FUNCTION(0x0, "gpio_in"),
-		  SUNXI_FUNCTION(0x1, "gpio_out")),
+		  SUNXI_FUNCTION(0x1, "gpio_out"),
+		/* Undocumented mux function - see above */
+		  SUNXI_FUNCTION(0x3, "spdif")),        /* SPDIF OUT */
 	SUNXI_PIN(SUNXI_PINCTRL_PIN(H, 29),
 		  SUNXI_FUNCTION(0x0, "gpio_in"),
 		  SUNXI_FUNCTION(0x1, "gpio_out"),