mtd: spinand: rework detect procedure for different READ_ID operation

Currently there are 3 different variants of read_id implementation:
1. opcode only. Found in GD5FxGQ4xF.
2. opcode + 1 addr byte. Found in GD5GxGQ4xA/E
3. opcode + 1 dummy byte. Found in other currently supported chips.

Original implementation was for variant 1 and let detect function
of chips with variant 2 and 3 to ignore the first byte. This isn't
robust:

1. For chips of variant 2, if SPI master doesn't keep MOSI low
during read, chip will get a random id offset, and the entire id
buffer will shift by that offset, causing detect failure.

2. For chips of variant 1, if it happens to get a devid that equals
to manufacture id of variant 2 or 3 chips, it'll get incorrectly
detected.

This patch reworks detect procedure to address problems above. New
logic do detection for all variants separatedly, in 1-2-3 order.
Since all current detect methods do exactly the same id matching
procedure, unify them into core.c and remove detect method from
manufacture_ops.

Tested on GD5F1GQ4UAYIG and W25N01GVZEIG.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200208074439.146296-1-gch981213@gmail.com

1 files changed, 6 insertions, 28 deletions

diff --git a/drivers/mtd/nand/spi/winbond.c b/drivers/mtd/nand/spi/winbond.c
index a6c17e0cace8..76684428354e 100644
--- a/drivers/mtd/nand/spi/winbond.c
+++ b/drivers/mtd/nand/spi/winbond.c
@@ -75,7 +75,8 @@ static int w25m02gv_select_target(struct spinand_device *spinand,
 }
 
 static const struct spinand_info winbond_spinand_table[] = {
-	SPINAND_INFO("W25M02GV", 0xAB,
+	SPINAND_INFO("W25M02GV",
+		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xab),
 		     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 2),
 		     NAND_ECCREQ(1, 512),
 		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
@@ -84,7 +85,8 @@ static const struct spinand_info winbond_spinand_table[] = {
 		     0,
 		     SPINAND_ECCINFO(&w25m02gv_ooblayout, NULL),
 		     SPINAND_SELECT_TARGET(w25m02gv_select_target)),
-	SPINAND_INFO("W25N01GV", 0xAA,
+	SPINAND_INFO("W25N01GV",
+		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xaa),
 		     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 1),
 		     NAND_ECCREQ(1, 512),
 		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
@@ -94,31 +96,6 @@ static const struct spinand_info winbond_spinand_table[] = {
 		     SPINAND_ECCINFO(&w25m02gv_ooblayout, NULL)),
 };
 
-/**
- * winbond_spinand_detect - initialize device related part in spinand_device
- * struct if it is a Winbond device.
- * @spinand: SPI NAND device structure
- */
-static int winbond_spinand_detect(struct spinand_device *spinand)
-{
-	u8 *id = spinand->id.data;
-	int ret;
-
-	/*
-	 * Winbond SPI NAND read ID need a dummy byte,
-	 * so the first byte in raw_id is dummy.
-	 */
-	if (id[1] != SPINAND_MFR_WINBOND)
-		return 0;
-
-	ret = spinand_match_and_init(spinand, winbond_spinand_table,
-				     ARRAY_SIZE(winbond_spinand_table), id[2]);
-	if (ret)
-		return ret;
-
-	return 1;
-}
-
 static int winbond_spinand_init(struct spinand_device *spinand)
 {
 	struct nand_device *nand = spinand_to_nand(spinand);
@@ -138,12 +115,13 @@ static int winbond_spinand_init(struct spinand_device *spinand)
 }
 
 static const struct spinand_manufacturer_ops winbond_spinand_manuf_ops = {
-	.detect = winbond_spinand_detect,
 	.init = winbond_spinand_init,
 };
 
 const struct spinand_manufacturer winbond_spinand_manufacturer = {
 	.id = SPINAND_MFR_WINBOND,
 	.name = "Winbond",
+	.chips = winbond_spinand_table,
+	.nchips = ARRAY_SIZE(winbond_spinand_table),
 	.ops = &winbond_spinand_manuf_ops,
 };