[PATCH v4 3/3] mtd: spi-nor: Add support for IS25LX256 operating in 1S-8S-8S octal read mode

[Nathan Barrett-Morrison]

This adds the IS25LX256 chip into the ISSI flash_info parts table

Signed-off-by: Nathan Barrett-Morrison <nathan.morrison@xxxxxxxxxxx>
---
 drivers/mtd/spi-nor/issi.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/mtd/spi-nor/issi.c b/drivers/mtd/spi-nor/issi.c
index 89a66a19d754..362bc3603d8f 100644
--- a/drivers/mtd/spi-nor/issi.c
+++ b/drivers/mtd/spi-nor/issi.c
@@ -29,6 +29,35 @@ static const struct spi_nor_fixups is25lp256_fixups = {
 	.post_bfpt = is25lp256_post_bfpt_fixups,
 };
 
+static int
+is25lx256_post_bfpt_fixups(struct spi_nor *nor,
+			   const struct sfdp_parameter_header *bfpt_header,
+			   const struct sfdp_bfpt *bfpt)
+{
+	/*
+	 * IS25LX256 supports both 1S-1S-8S and 1S-8S-8S.
+	 * However, the BFPT does not contain any information denoting this
+	 * functionality, so the proper fast read opcodes are never setup.
+	 * We're correcting this issue via the fixup below.  Page program
+	 * commands are detected and setup properly via the 4BAIT lookup.
+	 */
+	params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
+	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
+				  0, 8, SPINOR_OP_READ_1_1_8,
+				  SNOR_PROTO_1_1_8);
+
+	params->hwcaps.mask |= SNOR_HWCAPS_READ_1_8_8;
+	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_8_8],
+				  0, 16, SPINOR_OP_READ_1_8_8,
+				  SNOR_PROTO_1_8_8);
+
+	return 0;
+}
+
+static const struct spi_nor_fixups is25lx256_fixups = {
+	.post_bfpt = is25lx256_post_bfpt_fixups,
+};
+
 static void pm25lv_nor_late_init(struct spi_nor *nor)
 {
 	struct spi_nor_erase_map *map = &nor->params->erase_map;
@@ -74,6 +103,9 @@ static const struct flash_info issi_nor_parts[] = {
 		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)
 		FIXUP_FLAGS(SPI_NOR_4B_OPCODES)
 		.fixups = &is25lp256_fixups },
+	{ "is25lx256", INFO(0x9d5a19, 0, 0, 0)
+		PARSE_SFDP
+		.fixups = &is25lx256_fixups },
 
 	/* PMC */
 	{ "pm25lv512",   INFO(0,        0, 32 * 1024,    2)
-- 
2.30.2