mtd: fsl_ifc_nand: wait tWB time, poll R/B before command execution

IFC_FIR_OP_CMD0 issues command for execution without checking flash
readiness. It may cause problem if flash is not ready. Instead use
IFC_FIR_OP_CW0 which Wait for tWB time and poll R/B to return high or
time-out, before issuing command.

NAND_CMD_READID command implemention does not fulfill above requirement. So
update its programming.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Hemant Nautiyal <hemant.nautiyal@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

drivers/mtd/nand/fsl_ifc_nand.c

@@ -389,7 +389,7 @@ static void fsl_ifc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 			timing = IFC_FIR_OP_RBCD;
 
 		out_be32(&ifc->ifc_nand.nand_fir0,
-				(IFC_FIR_OP_CMD0 << IFC_NAND_FIR0_OP0_SHIFT) |
+				(IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
 				(IFC_FIR_OP_UA  << IFC_NAND_FIR0_OP1_SHIFT) |
 				(timing << IFC_NAND_FIR0_OP2_SHIFT));
 		out_be32(&ifc->ifc_nand.nand_fcr0,
@@ -754,7 +754,7 @@ static void fsl_ifc_sram_init(struct fsl_ifc_mtd *priv)
 
 	/* READID */
 	out_be32(&ifc->ifc_nand.nand_fir0,
-			(IFC_FIR_OP_CMD0 << IFC_NAND_FIR0_OP0_SHIFT) |
+			(IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
 			(IFC_FIR_OP_UA  << IFC_NAND_FIR0_OP1_SHIFT) |
 			(IFC_FIR_OP_RB << IFC_NAND_FIR0_OP2_SHIFT));
 	out_be32(&ifc->ifc_nand.nand_fcr0,