[PATCH 2/4] mtd: spi-nor-core: Track flash's internal address mode

[tkuw584924 at gmail.com]

From: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>

The nor->addr_width tracks number of address bytes used in
read/program/erase ops and eventually set to 4 for >16MB chips, regardless
of flash's internal address mode. For Infineon SEMPER flash's, we use
Read/Write Any Register commands for configuration and status check.
These commands take 3- or 4-byte address depending on flash's internal
address mode.

Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
---
 drivers/mtd/spi/spi-nor-core.c | 2 ++
 include/linux/mtd/spi-nor.h    | 5 +++++
 2 files changed, 7 insertions(+)

diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index 90d0f769f0..360fc9aff1 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -2215,10 +2215,12 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 	case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
 	case BFPT_DWORD1_ADDRESS_BYTES_3_OR_4:
 		nor->addr_width = 3;
+		nor->addr_mode_nbytes = 3;
 		break;
 
 	case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
 		nor->addr_width = 4;
+		nor->addr_mode_nbytes = 4;
 		break;
 
 	default:
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 2595bad9df..4422fd006d 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -493,6 +493,10 @@ struct spi_flash {
  * @rdsr_dummy		dummy cycles needed for Read Status Register command.
  * @rdsr_addr_nbytes:	dummy address bytes needed for Read Status Register
  *			command.
+ * @addr_mode_nbytes:	number of address bytes of current address mode. Useful
+ *			when the flash operates with 4B opcodes but needs the
+ *			internal address mode for opcodes that don't have a 4B
+ *			opcode correspondent.
  * @bank_read_cmd:	Bank read cmd
  * @bank_write_cmd:	Bank write cmd
  * @bank_curr:		Current flash bank
@@ -538,6 +542,7 @@ struct spi_nor {
 	u8			program_opcode;
 	u8			rdsr_dummy;
 	u8			rdsr_addr_nbytes;
+	u8			addr_mode_nbytes;
 #ifdef CONFIG_SPI_FLASH_BAR
 	u8			bank_read_cmd;
 	u8			bank_write_cmd;
-- 
2.25.1