mtd: brcmnand: Add support for v6.2 controllers

Document and match the brcm,brcmnand-v6.2 compatible string, the controller has
a register layout identical to the v6.0 version and supports prefetch. Update the
command shift logic to account for v6.2 controller which are the first ones to
use a shift of 0 (6.1 used a shift of 24).

Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt

@@ -24,6 +24,7 @@ Required properties:
                          brcm,brcmnand-v5.0
                          brcm,brcmnand-v6.0
                          brcm,brcmnand-v6.1
+                         brcm,brcmnand-v6.2
                          brcm,brcmnand-v7.0
                          brcm,brcmnand-v7.1
                          brcm,brcmnand

drivers/mtd/nand/brcmnand/brcmnand.c

@@ -601,7 +601,7 @@ static void brcmnand_wr_corr_thresh(struct brcmnand_host *host, u8 val)
 
 static inline int brcmnand_cmd_shift(struct brcmnand_controller *ctrl)
 {
-	if (ctrl->nand_version < 0x0700)
+	if (ctrl->nand_version < 0x0602)
 		return 24;
 	return 0;
 }
@@ -2115,6 +2115,7 @@ static const struct of_device_id brcmnand_of_match[] = {
 	{ .compatible = "brcm,brcmnand-v5.0" },
 	{ .compatible = "brcm,brcmnand-v6.0" },
 	{ .compatible = "brcm,brcmnand-v6.1" },
+	{ .compatible = "brcm,brcmnand-v6.2" },
 	{ .compatible = "brcm,brcmnand-v7.0" },
 	{ .compatible = "brcm,brcmnand-v7.1" },
 	{},