mtd: nand: davinci: remove custom 'erased check' implementation

The davinci driver is manually checking for 'erased pages' while
correcting ECC bytes.
This logic can now done by the core infrastructure, and can thus be removed
from this driver.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: NFranklin S Cooper Jr. <fcooper@ti.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

drivers/mtd/nand/davinci_nand.c

@@ -317,14 +317,6 @@ static int nand_davinci_correct_4bit(struct mtd_info *mtd,
 	unsigned num_errors, corrected;
 	unsigned long timeo;
 
-	/* All bytes 0xff?  It's an erased page; ignore its ECC. */
-	for (i = 0; i < 10; i++) {
-		if (ecc_code[i] != 0xff)
-			goto compare;
-	}
-	return 0;
-
-compare:
 	/* Unpack ten bytes into eight 10 bit values.  We know we're
 	 * little-endian, and use type punning for less shifting/masking.
 	 */
@@ -749,6 +741,7 @@ static int nand_davinci_probe(struct platform_device *pdev)
 			info->chip.ecc.correct = nand_davinci_correct_4bit;
 			info->chip.ecc.hwctl = nand_davinci_hwctl_4bit;
 			info->chip.ecc.bytes = 10;
+			info->chip.ecc.options = NAND_ECC_GENERIC_ERASED_CHECK;
 		} else {
 			info->chip.ecc.calculate = nand_davinci_calculate_1bit;
 			info->chip.ecc.correct = nand_davinci_correct_1bit;