dt-bindings: ti,omap-hsmmc: Add 66AK2G mmc controller

Update the ti,omap-hsmmc.txt to include information about
66AK2G specific mmc controller. Also cleanup the entries
under optional properties to look a bit nicer.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>

Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt

-* TI Highspeed MMC host controller for OMAP
+* TI Highspeed MMC host controller for OMAP and 66AK2G family.
 
-The Highspeed MMC Host Controller on TI OMAP family
+The Highspeed MMC Host Controller on TI OMAP and 66AK2G family
 provides an interface for MMC, SD, and SDIO types of memory cards.
 
 This file documents differences between the core properties described
 by mmc.txt and the properties used by the omap_hsmmc driver.
 
 Required properties:
+--------------------
 - compatible:
  Should be "ti,omap2-hsmmc", for OMAP2 controllers
  Should be "ti,omap3-hsmmc", for OMAP3 controllers
  Should be "ti,omap3-pre-es3-hsmmc" for OMAP3 controllers pre ES3.0
  Should be "ti,omap4-hsmmc", for OMAP4 controllers
  Should be "ti,am33xx-hsmmc", for AM335x controllers
-- ti,hwmods: Must be "mmc<n>", n is controller instance starting 1
+ Should be "ti,k2g-hsmmc", "ti,omap4-hsmmc" for 66AK2G controllers.
+
+SoC specific required properties:
+---------------------------------
+The following are mandatory properties for OMAPs, AM33xx and AM43xx SoCs only:
+- ti,hwmods: Must be "mmc<n>", n is controller instance starting 1.
+
+The following are mandatory properties for 66AK2G SoCs only:
+- power-domains:Should contain a phandle to a PM domain provider node
+		and an args specifier containing the MMC device id
+		value. This property is as per the binding,
+		Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt
+- clocks:	Must contain an entry for each entry in clock-names. Should
+		be defined as per the he appropriate clock bindings consumer
+		usage in Documentation/devicetree/bindings/clock/ti,sci-clk.txt
+- clock-names:	Shall be "fck" for the functional clock,
+		and "mmchsdb_fck" for the debounce clock.
+
 
 Optional properties:
-ti,dual-volt: boolean, supports dual voltage cards
-<supply-name>-supply: phandle to the regulator device tree node
-"supply-name" examples are "vmmc", "vmmc_aux"(deprecated)/"vqmmc" etc
-ti,non-removable: non-removable slot (like eMMC)
-ti,needs-special-reset: Requires a special softreset sequence
-ti,needs-special-hs-handling: HSMMC IP needs special setting for handling High Speed
-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: List of DMA request names. These strings correspond
-1:1 with the DMA specifiers listed in dmas. The string naming is
-to be "rx" and "tx" for RX and TX DMA requests, respectively.
+--------------------
+- ti,dual-volt:		boolean, supports dual voltage cards
+- <supply-name>-supply:	phandle to the regulator device tree node
+			  "supply-name" examples are "vmmc",
+			  "vmmc_aux"(deprecated)/"vqmmc" etc
+- ti,non-removable:	non-removable slot (like eMMC)
+- ti,needs-special-reset:	Requires a special softreset sequence
+- ti,needs-special-hs-handling:	HSMMC IP needs special setting
+				  for handling High Speed
+- 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:		List of DMA request names. These strings correspond
+			1:1 with the DMA specifiers listed in dmas.
+			The string naming is to be "rx" and "tx" for
+			RX and TX DMA requests, respectively.
 
 Examples: