mtd: nand: use usual return values for the ->erase() hook

Avoid using specific defined values for checking returned status of the
->erase() hook. Instead, use usual negative error values on failure,
zero otherwise.
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/nand/denali.c

@@ -951,7 +951,7 @@ static int denali_erase(struct mtd_info *mtd, int page)
 	irq_status = denali_wait_for_irq(denali,
 					 INTR__ERASE_COMP | INTR__ERASE_FAIL);
 
-	return irq_status & INTR__ERASE_COMP ? 0 : NAND_STATUS_FAIL;
+	return irq_status & INTR__ERASE_COMP ? 0 : -EIO;
 }
 
 static int denali_setup_data_interface(struct mtd_info *mtd, int chipnr,

drivers/mtd/nand/docg4.c

@@ -900,6 +900,7 @@ static int docg4_erase_block(struct mtd_info *mtd, int page)
 	struct docg4_priv *doc = nand_get_controller_data(nand);
 	void __iomem *docptr = doc->virtadr;
 	uint16_t g4_page;
+	int status;
 
 	dev_dbg(doc->dev, "%s: page %04x\n", __func__, page);
 
@@ -939,7 +940,11 @@ static int docg4_erase_block(struct mtd_info *mtd, int page)
 	poll_status(doc);
 	write_nop(docptr);
 
-	return nand->waitfunc(mtd, nand);
+	status = nand->waitfunc(mtd, nand);
+	if (status < 0)
+		return status;
+
+	return status & NAND_STATUS_FAIL ? -EIO : 0;
 }
 
 static int write_page(struct mtd_info *mtd, struct nand_chip *nand,

drivers/mtd/nand/nand_base.c

@@ -2989,11 +2989,17 @@ static int nand_write_oob(struct mtd_info *mtd, loff_t to,
 static int single_erase(struct mtd_info *mtd, int page)
 {
 	struct nand_chip *chip = mtd_to_nand(mtd);
+	int status;
+
 	/* Send commands to erase a block */
 	chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
 	chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
 
-	return chip->waitfunc(mtd, chip);
+	status = chip->waitfunc(mtd, chip);
+	if (status < 0)
+		return status;
+
+	return status & NAND_STATUS_FAIL ? -EIO : 0;
 }
 
 /**
@@ -3077,7 +3083,7 @@ int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
 		status = chip->erase(mtd, page & chip->pagemask);
 
 		/* See if block erase succeeded */
-		if (status & NAND_STATUS_FAIL) {
+		if (status) {
 			pr_debug("%s: failed erase, page 0x%08x\n",
 					__func__, page);
 			instr->state = MTD_ERASE_FAILED;