[PATCH v4 4/6] mtd: rawnand: micron: add fixup for ONFI revision

[Chris Packham]

Some Micron NAND chips (MT29F1G08ABAFAWP-ITE:F) report 00 00 for the
revision number field of the ONFI parameter page. Rather than rejecting
these outright assume ONFI version 1.0 if the revision number is 00 00.

Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>
---
This is now qualified on vendor == MICRON. I haven't qualified this
based on specific chips the ABAFA (id=d1) and ABBFA (id=a1) variants are
documented to have this behaviour.

Changes in v2:
- use fixup_onfi_param_page
Changes in v3:
- add code comment next to workaround
Changes in v4:
- use define for ONFI_VERSION

 drivers/mtd/nand/raw/nand_micron.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/mtd/nand/raw/nand_micron.c b/drivers/mtd/nand/raw/nand_micron.c
index 203faba0a9c1..d30bd4df9b12 100644
--- a/drivers/mtd/nand/raw/nand_micron.c
+++ b/drivers/mtd/nand/raw/nand_micron.c
@@ -290,6 +290,19 @@ static int micron_nand_init(struct nand_chip *chip)
 	return 0;
 }
 
+static void micron_fixup_onfi_param_page(struct nand_chip *chip,
+					 struct nand_onfi_params *p)
+{
+	/*
+	 * MT29F1G08ABAFAWP-ITE:F and possibly others report 00 00 for the
+	 * revision number field of the ONFI parameter page. Assume ONFI
+	 * version 1.0 if the revision number is 00 00.
+	 */
+	if (le16_to_cpu(p->revision) == 0)
+		p->revision = cpu_to_le16(ONFI_VERSION_1_0);
+}
+
 const struct nand_manufacturer_ops micron_nand_manuf_ops = {
 	.init = micron_nand_init,
+	.fixup_onfi_param_page = micron_fixup_onfi_param_page,
 };
-- 
2.17.1