dt-bindings: Add devicetree bindings

Add snapshot of device tree bindings from keystone common kernel, branch
"android-mainline-keystone-qcom-release" at c4c12103f9c0 ("Snap for 9228065
from e32903b9a63bb558df8b803b076619c53c16baad to
android-mainline-keystone-qcom-release").

Change-Id: I7682079615cbd9f29340a5c1f2a1d84ec441a1f1
Signed-off-by: Melody Olvera <quic_molvera@quicinc.com>

bindings/mmc/davinci_mmc.txt

@@ -0,0 +1,32 @@
+* TI Highspeed MMC host controller for DaVinci
+
+The Highspeed MMC Host Controller on TI DaVinci family
+provides an interface for MMC, SD and SDIO types of memory cards.
+
+This file documents the properties used by the davinci_mmc driver.
+
+Required properties:
+- compatible:
+ Should be "ti,da830-mmc": for da830, da850, dm365
+ Should be "ti,dm355-mmc": for dm355, dm644x
+
+Optional properties:
+- bus-width: Number of data lines, can be <1>, <4>, or <8>, default <1>
+- max-frequency: Maximum operating clock frequency, default 25MHz.
+- dmas: List of DMA specifiers with the controller specific format
+	as described in the generic DMA client binding. A tx and rx
+	specifier is required.
+- dma-names: RX and TX  DMA request names. These strings correspond
+	1:1 with the DMA specifiers listed in dmas.
+
+Example:
+mmc0: mmc@1c40000 {
+	compatible = "ti,da830-mmc",
+	reg = <0x40000 0x1000>;
+	interrupts = <16>;
+	bus-width = <4>;
+	max-frequency = <50000000>;
+	dmas = <&edma 16
+		&edma 17>;
+	dma-names = "rx", "tx";
+};