From c67cbb839da9cc2757eabfa128556db6a2baf160 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Tue, 10 Nov 2015 12:15:27 -0800 Subject: [PATCH] mtd: spi-nor: provide default erase_sector implementation Some spi-nor drivers perform sector erase by duplicating their write_reg() command. Let's not require that the driver fill this out, and provide a default instead. Tested on m25p80.c and Medatek's MT8173 SPI NOR flash driver. Signed-off-by: Brian Norris --- drivers/mtd/spi-nor/spi-nor.c | 37 +++++++++++++++++++++++++++++++---- include/linux/mtd/spi-nor.h | 3 ++- 2 files changed, 35 insertions(+), 5 deletions(-) diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 16c9f5522b8f..a38ec01a1e06 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -38,6 +38,7 @@ #define CHIP_ERASE_2MB_READY_WAIT_JIFFIES (40UL * HZ) #define SPI_NOR_MAX_ID_LEN 6 +#define SPI_NOR_MAX_ADDR_WIDTH 4 struct flash_info { char *name; @@ -312,6 +313,29 @@ static void spi_nor_unlock_and_unprep(struct spi_nor *nor, enum spi_nor_ops ops) mutex_unlock(&nor->lock); } +/* + * Initiate the erasure of a single sector + */ +static int spi_nor_erase_sector(struct spi_nor *nor, u32 addr) +{ + u8 buf[SPI_NOR_MAX_ADDR_WIDTH]; + int i; + + if (nor->erase) + return nor->erase(nor, addr); + + /* + * Default implementation, if driver doesn't have a specialized HW + * control + */ + for (i = nor->addr_width - 1; i >= 0; i--) { + buf[i] = addr & 0xff; + addr >>= 8; + } + + return nor->write_reg(nor, nor->erase_opcode, buf, nor->addr_width); +} + /* * Erase an address range on the nor chip. The address range may extend * one or more erase sectors. Return an error is there is a problem erasing. @@ -371,10 +395,9 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) while (len) { write_enable(nor); - if (nor->erase(nor, addr)) { - ret = -EIO; + ret = spi_nor_erase_sector(nor, addr); + if (ret) goto erase_err; - } addr += mtd->erasesize; len -= mtd->erasesize; @@ -1138,7 +1161,7 @@ static int set_quad_mode(struct spi_nor *nor, const struct flash_info *info) static int spi_nor_check(struct spi_nor *nor) { if (!nor->dev || !nor->read || !nor->write || - !nor->read_reg || !nor->write_reg || !nor->erase) { + !nor->read_reg || !nor->write_reg) { pr_err("spi-nor: please fill all the necessary fields!\n"); return -EINVAL; } @@ -1340,6 +1363,12 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) nor->addr_width = 3; } + if (nor->addr_width > SPI_NOR_MAX_ADDR_WIDTH) { + dev_err(dev, "address width is too large: %u\n", + nor->addr_width); + return -EINVAL; + } + nor->read_dummy = spi_nor_read_dummy_cycles(nor); dev_info(dev, "%s (%lld Kbytes)\n", info->name, diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 955f268d159a..7bed97471e53 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -143,7 +143,8 @@ struct mtd_info; * @read: [DRIVER-SPECIFIC] read data from the SPI NOR * @write: [DRIVER-SPECIFIC] write data to the SPI NOR * @erase: [DRIVER-SPECIFIC] erase a sector of the SPI NOR - * at the offset @offs + * at the offset @offs; if not provided by the driver, + * spi-nor will send the erase opcode via write_reg() * @flash_lock: [FLASH-SPECIFIC] lock a region of the SPI NOR * @flash_unlock: [FLASH-SPECIFIC] unlock a region of the SPI NOR * @flash_is_locked: [FLASH-SPECIFIC] check if a region of the SPI NOR is -- 2.20.1