[RFC PATCH 1/2] mtd: spi-nor: atmel: remove global SNOR_F_HAS_LOCK

Michael Walle michael at walle.cc
Thu Oct 1 08:28:27 EDT 2020


This is considered bad for the following reasons:
 (1) We only support the block protection with BPn bits for write
     protection. Not all Atmel parts support this.
 (2) Newly added flash chip will automatically inherit the "has
     locking" support and thus needs to explicitly tested. Better
     be opt-in instead of opt-out.
 (3) There are already supported flashes which don't support the locking
	 scheme. So I assume this wasn't properly tested before adding that
	 chip; which enforces my previous argument that locking support should
	 be an opt-in.

Remove the global flag and add individual flags to all flashes
which supports BP locking. In particular the following flashes
don't support the BP scheme:
 - AT26F004
 - AT25SL321
 - AT45DB081D

Signed-off-by: Michael Walle <michael at walle.cc>
---
 drivers/mtd/spi-nor/atmel.c | 28 +++++++++-------------------
 1 file changed, 9 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/spi-nor/atmel.c b/drivers/mtd/spi-nor/atmel.c
index 3f5f21a473a6..49d392c6c8bc 100644
--- a/drivers/mtd/spi-nor/atmel.c
+++ b/drivers/mtd/spi-nor/atmel.c
@@ -10,37 +10,27 @@
 
 static const struct flash_info atmel_parts[] = {
 	/* Atmel -- some are (confusingly) marketed as "DataFlash" */
-	{ "at25fs010",  INFO(0x1f6601, 0, 32 * 1024,   4, SECT_4K) },
-	{ "at25fs040",  INFO(0x1f6604, 0, 64 * 1024,   8, SECT_4K) },
+	{ "at25fs010",  INFO(0x1f6601, 0, 32 * 1024,   4, SECT_4K | SPI_NOR_HAS_LOCK) },
+	{ "at25fs040",  INFO(0x1f6604, 0, 64 * 1024,   8, SECT_4K | SPI_NOR_HAS_LOCK) },
 
-	{ "at25df041a", INFO(0x1f4401, 0, 64 * 1024,   8, SECT_4K) },
-	{ "at25df321",  INFO(0x1f4700, 0, 64 * 1024,  64, SECT_4K) },
-	{ "at25df321a", INFO(0x1f4701, 0, 64 * 1024,  64, SECT_4K) },
-	{ "at25df641",  INFO(0x1f4800, 0, 64 * 1024, 128, SECT_4K) },
+	{ "at25df041a", INFO(0x1f4401, 0, 64 * 1024,   8, SECT_4K | SPI_NOR_HAS_LOCK) },
+	{ "at25df321",  INFO(0x1f4700, 0, 64 * 1024,  64, SECT_4K | SPI_NOR_HAS_LOCK) },
+	{ "at25df321a", INFO(0x1f4701, 0, 64 * 1024,  64, SECT_4K | SPI_NOR_HAS_LOCK) },
+	{ "at25df641",  INFO(0x1f4800, 0, 64 * 1024, 128, SECT_4K | SPI_NOR_HAS_LOCK) },
 
 	{ "at25sl321",	INFO(0x1f4216, 0, 64 * 1024, 64,
 			     SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
 
 	{ "at26f004",   INFO(0x1f0400, 0, 64 * 1024,  8, SECT_4K) },
-	{ "at26df081a", INFO(0x1f4501, 0, 64 * 1024, 16, SECT_4K) },
-	{ "at26df161a", INFO(0x1f4601, 0, 64 * 1024, 32, SECT_4K) },
-	{ "at26df321",  INFO(0x1f4700, 0, 64 * 1024, 64, SECT_4K) },
+	{ "at26df081a", INFO(0x1f4501, 0, 64 * 1024, 16, SECT_4K | SPI_NOR_HAS_LOCK) },
+	{ "at26df161a", INFO(0x1f4601, 0, 64 * 1024, 32, SECT_4K | SPI_NOR_HAS_LOCK) },
+	{ "at26df321",  INFO(0x1f4700, 0, 64 * 1024, 64, SECT_4K | SPI_NOR_HAS_LOCK) },
 
 	{ "at45db081d", INFO(0x1f2500, 0, 64 * 1024, 16, SECT_4K) },
 };
 
-static void atmel_default_init(struct spi_nor *nor)
-{
-	nor->flags |= SNOR_F_HAS_LOCK;
-}
-
-static const struct spi_nor_fixups atmel_fixups = {
-	.default_init = atmel_default_init,
-};
-
 const struct spi_nor_manufacturer spi_nor_atmel = {
 	.name = "atmel",
 	.parts = atmel_parts,
 	.nparts = ARRAY_SIZE(atmel_parts),
-	.fixups = &atmel_fixups,
 };
-- 
2.20.1




More information about the linux-mtd mailing list