--- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -142,20 +142,29 @@ static int read_fsr(struct spi_nor *nor) * location. Return the configuration register value. * Returns negative if error occurred. */ -static int read_cr(struct spi_nor *nor) +static int _read_cr(struct spi_nor *nor, u8 reg) { int ret; u8 val; - ret = nor->read_reg(nor, SPINOR_OP_RDCR, &val, 1); + ret = nor->read_reg(nor, reg, &val, 1); if (ret < 0) { - dev_err(nor->dev, "error %d reading CR\n", ret); + dev_err(nor->dev, "error %d reading %s\n", ret, + (reg==SPINOR_OP_RDCR)?"CR":"XCR"); return ret; } return val; } +static inline int read_cr(struct spi_nor *nor) { + return _read_cr(nor, SPINOR_OP_RDCR); +} + +static inline int read_xcr(struct spi_nor *nor) { + return _read_cr(nor, SPINOR_OP_RDXCR); +} + /* * Write status register 1 byte * Returns negative if error occurred. @@ -2895,9 +2904,16 @@ int spi_nor_scan(struct spi_nor *nor, co } else if (mtd->size > 0x1000000) { /* enable 4-byte addressing if the device exceeds 16MiB */ nor->addr_width = 4; - if (info->flags & SPI_NOR_4B_READ_OP) - spi_nor_set_4byte_read(nor, info); - else if (JEDEC_MFR(info) == SNOR_MFR_SPANSION || + if (info->flags & SPI_NOR_4B_READ_OP) { + if (JEDEC_MFR(info) == SNOR_MFR_WINBOND) { + ret = read_xcr(nor); + if (!(ret > 0 && (ret & XCR_DEF_4B_ADDR_MODE))) + spi_nor_set_4byte_read(nor, info); + else + set_4byte(nor, info, 1); + } else + spi_nor_set_4byte_read(nor, info); + } else if (JEDEC_MFR(info) == SNOR_MFR_SPANSION || info->flags & SPI_NOR_4B_OPCODES) spi_nor_set_4byte_opcodes(nor, info); else --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -103,6 +103,7 @@ #define SPINOR_OP_EN4B 0xb7 /* Enter 4-byte mode */ #define SPINOR_OP_EX4B 0xe9 /* Exit 4-byte mode */ #define SPINOR_OP_WREAR 0xc5 /* Write extended address register */ +#define SPINOR_OP_RDXCR 0x15 /* Read extended configuration register */ /* Used for Spansion flashes only. */ #define SPINOR_OP_BRWR 0x17 /* Bank register write */ @@ -135,6 +136,7 @@ /* Configuration Register bits. */ #define CR_QUAD_EN_SPAN BIT(1) /* Spansion Quad I/O */ +#define XCR_DEF_4B_ADDR_MODE BIT(1) /* Winbond 4B mode default */ /* Status Register 2 bits. */ #define SR2_QUAD_EN_BIT7 BIT(7)