[PATCH 1/2] mtd: spi-nor: do not touch TB bit without SPI_NOR_HAS_TB

Ivan Mikhaylov i.mikhaylov at yadro.com
Wed Aug 12 11:18:17 EDT 2020


Some chips like macronix don't have TB(Top/Bottom protection)
bit in the status register. Do not write tb_mask inside status
register, unless SPI_NOR_HAS_TB is present for the chip.

Signed-off-by: Ivan Mikhaylov <i.mikhaylov at yadro.com>
---
 drivers/mtd/spi-nor/core.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 0369d98b2d12..f9853dd566dc 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -1735,13 +1735,18 @@ static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 			return -EINVAL;
 	}
 
-	status_new = (status_old & ~mask & ~tb_mask) | val;
+	if (nor->flags & SNOR_F_HAS_SR_TB)
+		status_new = (status_old & ~mask & ~tb_mask) | val;
+	else
+		status_new = (status_old & ~mask) | val;
 
 	/* Disallow further writes if WP pin is asserted */
 	status_new |= SR_SRWD;
 
-	if (!use_top)
-		status_new |= tb_mask;
+	if (!use_top) {
+		if (nor->flags & SNOR_F_HAS_SR_TB)
+			status_new |= tb_mask;
+	}
 
 	/* Don't bother if they're the same */
 	if (status_new == status_old)
@@ -1817,14 +1822,19 @@ static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 			return -EINVAL;
 	}
 
-	status_new = (status_old & ~mask & ~tb_mask) | val;
+	if (nor->flags & SNOR_F_HAS_SR_TB)
+		status_new = (status_old & ~mask & ~tb_mask) | val;
+	else
+		status_new = (status_old & ~mask) | val;
 
 	/* Don't protect status register if we're fully unlocked */
 	if (lock_len == 0)
 		status_new &= ~SR_SRWD;
 
-	if (!use_top)
-		status_new |= tb_mask;
+	if (!use_top) {
+		if (nor->flags & SNOR_F_HAS_SR_TB)
+			status_new |= tb_mask;
+	}
 
 	/* Don't bother if they're the same */
 	if (status_new == status_old)
-- 
2.21.1




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