[PATCH 3/7] mtd: spi-nor: macronix: Handle ID collision b/w MX25L3233F and MX25L3205D

[Tudor Ambarus]

Macronix has a bad habbit of reusing flash IDs. While MX25L3233F supports
RDSFDP opcode, MX25L3205D does not support it and does not recommend
issuing opcodes that are not supported ("It is not recommended to adopt
any other code not in the command definition table, which will potentially
enter the hidden mode.").

We tested the RDSFDP on the MX25L3205D and the conclusion is that the
flash didn't reply anything. Given that it is unlikely that RDSFDP will
cause any problems for the old MX25L3205D, differentiate between the two
flashes by parsing SFDP.

Signed-off-by: Tudor Ambarus <tudor.ambarus at microchip.com>
---
 drivers/mtd/spi-nor/macronix.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/spi-nor/macronix.c b/drivers/mtd/spi-nor/macronix.c
index 27498ed0cc0d..83a097708949 100644
--- a/drivers/mtd/spi-nor/macronix.c
+++ b/drivers/mtd/spi-nor/macronix.c
@@ -8,6 +8,26 @@
 
 #include "core.h"
 
+static const char *mx25l3233f = "mx25l3233f";
+
+static int mx25l3233f_post_bfpt_fixups(struct spi_nor *nor,
+				const struct sfdp_parameter_header *bfpt_header,
+				const struct sfdp_bfpt *bfpt)
+{
+	/*
+	 * Macronix has a bad habit of reusing flash IDs: MX25L3233F collides
+	 * with MX25L3205D. MX25L3233F defines SFDP tables, while the older
+	 * variant does not.
+	 */
+	nor->name = mx25l3233f;
+
+	return 0;
+}
+
+static struct spi_nor_fixups mx25l3233f_fixups = {
+	.post_bfpt = mx25l3233f_post_bfpt_fixups,
+};
+
 static int
 mx25l25635_post_bfpt_fixups(struct spi_nor *nor,
 			    const struct sfdp_parameter_header *bfpt_header,
@@ -39,7 +59,9 @@ static const struct flash_info macronix_parts[] = {
 	{ "mx25l4005a",  INFO(0xc22013, 0, 64 * 1024,   8, SECT_4K) },
 	{ "mx25l8005",   INFO(0xc22014, 0, 64 * 1024,  16, 0) },
 	{ "mx25l1606e",  INFO(0xc22015, 0, 64 * 1024,  32, SECT_4K) },
-	{ "mx25l3205d",  INFO(0xc22016, 0, 64 * 1024,  64, SECT_4K) },
+	{ "mx25l3205d",  INFO(0xc22016, 0, 64 * 1024,  64, SPI_NOR_PARSE_SFDP |
+			      SECT_4K)
+		.fixups = &mx25l3233f_fixups },
 	{ "mx25l3255e",  INFO(0xc29e16, 0, 64 * 1024,  64, SECT_4K) },
 	{ "mx25l6405d",  INFO(0xc22017, 0, 64 * 1024, 128, SECT_4K) },
 	{ "mx25u2033e",  INFO(0xc22532, 0, 64 * 1024,   4, SECT_4K) },
-- 
2.25.1