[PATCH v5 1/3] mtd: nand: don't select chip in nand_chip's block_bad op

[Archit Taneja]

One of the arguments passed to struct nand_chip's block_bad op is
'getchip', which, if true, is supposed to get and select the nand device,
and later unselect and release the device.

This op is intended to be replaceable by drivers. The drivers shouldn't
be responsible for selecting/unselecting chip. Like other ops, the chip
should already be selected before the block_bad op is called.

Remove the getchip argument from the block_bad op and move the chip
selection to nand_block_checkbad (the only user of chip->block_bad).
Modify nand_block_bad (the default function for the op) such that
it doesn't select the chip.

Signed-off-by: Archit Taneja <architt at codeaurora.org>
---
 drivers/mtd/nand/nand_base.c | 41 +++++++++++++++++++++++------------------
 include/linux/mtd/nand.h     |  2 +-
 2 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 928081b..42aa441 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -317,9 +317,9 @@ static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
  *
  * Check, if the block is bad.
  */
-static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
+static int nand_block_bad(struct mtd_info *mtd, loff_t ofs)
 {
-	int page, chipnr, res = 0, i = 0;
+	int page, res = 0, i = 0;
 	struct nand_chip *chip = mtd_to_nand(mtd);
 	u16 bad;
 
@@ -328,15 +328,6 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
 
 	page = (int)(ofs >> chip->page_shift) & chip->pagemask;
 
-	if (getchip) {
-		chipnr = (int)(ofs >> chip->chip_shift);
-
-		nand_get_device(mtd, FL_READING);
-
-		/* Select the NAND device */
-		chip->select_chip(mtd, chipnr);
-	}
-
 	do {
 		if (chip->options & NAND_BUSWIDTH_16) {
 			chip->cmdfunc(mtd, NAND_CMD_READOOB,
@@ -361,11 +352,6 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
 		i++;
 	} while (!res && i < 2 && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE));
 
-	if (getchip) {
-		chip->select_chip(mtd, -1);
-		nand_release_device(mtd);
-	}
-
 	return res;
 }
 
@@ -514,8 +500,27 @@ static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
 {
 	struct nand_chip *chip = mtd_to_nand(mtd);
 
-	if (!chip->bbt)
-		return chip->block_bad(mtd, ofs, getchip);
+	if (!chip->bbt) {
+		int ret;
+
+		if (getchip) {
+			int chipnr = (int)(ofs >> chip->chip_shift);
+
+			nand_get_device(mtd, FL_READING);
+
+			/* Select the NAND device */
+			chip->select_chip(mtd, chipnr);
+		}
+
+		ret = chip->block_bad(mtd, ofs);
+
+		if (getchip) {
+			chip->select_chip(mtd, -1);
+			nand_release_device(mtd);
+		}
+
+		return ret;
+	}
 
 	/* Return info from the table */
 	return nand_isbad_bbt(mtd, ofs, allowbbt);
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 3e92be1..c15818e 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -650,7 +650,7 @@ struct nand_chip {
 	void (*write_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
 	void (*read_buf)(struct mtd_info *mtd, uint8_t *buf, int len);
 	void (*select_chip)(struct mtd_info *mtd, int chip);
-	int (*block_bad)(struct mtd_info *mtd, loff_t ofs, int getchip);
+	int (*block_bad)(struct mtd_info *mtd, loff_t ofs);
 	int (*block_markbad)(struct mtd_info *mtd, loff_t ofs);
 	void (*cmd_ctrl)(struct mtd_info *mtd, int dat, unsigned int ctrl);
 	int (*dev_ready)(struct mtd_info *mtd);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation