ARM: OMAP2+: Convert NAND to retrieve GPMC settings from DT

When booting with device-tree, retrieve GPMC settings for NAND from
the device-tree blob. This will allow us to remove all static settings
stored in the gpmc-nand.c in the future once the migration to
device-tree is complete.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
diff --git a/arch/arm/mach-omap2/gpmc-nand.c b/arch/arm/mach-omap2/gpmc-nand.c
index 12e9753..d9c2719 100644
--- a/arch/arm/mach-omap2/gpmc-nand.c
+++ b/arch/arm/mach-omap2/gpmc-nand.c
@@ -137,12 +137,16 @@
 			return err;
 		}
 
-		s.device_nand = true;
+		if (gpmc_nand_data->of_node) {
+			gpmc_read_settings_dt(gpmc_nand_data->of_node, &s);
+		} else {
+			s.device_nand = true;
 
-		/* Enable RD PIN Monitoring Reg */
-		if (gpmc_nand_data->dev_ready) {
-			s.wait_on_read = true;
-			s.wait_on_write = true;
+			/* Enable RD PIN Monitoring Reg */
+			if (gpmc_nand_data->dev_ready) {
+				s.wait_on_read = true;
+				s.wait_on_write = true;
+			}
 		}
 
 		if (gpmc_nand_data->devsize == NAND_BUSWIDTH_16)