From 7854643a91eade84112dca9768eeb8d32463d101 Mon Sep 17 00:00:00 2001 From: Chen Gong Date: Wed, 26 Nov 2008 10:23:57 +0000 Subject: [PATCH] [MTD] m25p80: chip erase != block erase != sector erase This fixes broken terminology added in the "m25p80.c erase enhance" patch, which added a chip erase command but called it "block erase". There are already two block erase commands; blocks are 4KiB or 32KiB. There's also a sector erase (usually 64 KiB). Chip erase typically covers Megabytes. OPCODE_BE ==> OPCODE_CHIP_ERASE erase_block ==> erase_chip [dbrownell@users.sourceforge.net: update sector erase comments too ] Signed-off-by: Chen Gong Signed-off-by: David Brownell Signed-off-by: Andrew Morton Signed-off-by: David Woodhouse --- drivers/mtd/devices/m25p80.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index 6188fd4ddcc0..6659b2275c0c 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -37,9 +37,9 @@ #define OPCODE_NORM_READ 0x03 /* Read data bytes (low frequency) */ #define OPCODE_FAST_READ 0x0b /* Read data bytes (high frequency) */ #define OPCODE_PP 0x02 /* Page program (up to 256 bytes) */ -#define OPCODE_BE_4K 0x20 /* Erase 4KiB block */ +#define OPCODE_BE_4K 0x20 /* Erase 4KiB block */ #define OPCODE_BE_32K 0x52 /* Erase 32KiB block */ -#define OPCODE_BE 0xc7 /* Erase whole flash block */ +#define OPCODE_CHIP_ERASE 0xc7 /* Erase whole flash chip */ #define OPCODE_SE 0xd8 /* Sector erase (usually 64KiB) */ #define OPCODE_RDID 0x9f /* Read JEDEC ID */ @@ -167,7 +167,7 @@ static int wait_till_ready(struct m25p *flash) * * Returns 0 if successful, non-zero otherwise. */ -static int erase_block(struct m25p *flash) +static int erase_chip(struct m25p *flash) { DEBUG(MTD_DEBUG_LEVEL3, "%s: %s %dKiB\n", flash->spi->dev.bus_id, __func__, @@ -181,7 +181,7 @@ static int erase_block(struct m25p *flash) write_enable(flash); /* Set up command buffer. */ - flash->command[0] = OPCODE_BE; + flash->command[0] = OPCODE_CHIP_ERASE; spi_write(flash->spi, flash->command, 1); @@ -250,15 +250,18 @@ static int m25p80_erase(struct mtd_info *mtd, struct erase_info *instr) mutex_lock(&flash->lock); - /* REVISIT in some cases we could speed up erasing large regions - * by using OPCODE_SE instead of OPCODE_BE_4K - */ - - /* now erase those sectors */ - if (len == flash->mtd.size && erase_block(flash)) { + /* whole-chip erase? */ + if (len == flash->mtd.size && erase_chip(flash)) { instr->state = MTD_ERASE_FAILED; mutex_unlock(&flash->lock); return -EIO; + + /* REVISIT in some cases we could speed up erasing large regions + * by using OPCODE_SE instead of OPCODE_BE_4K. We may have set up + * to use "small sector erase", but that's not always optimal. + */ + + /* "sector"-at-a-time erase */ } else { while (len) { if (erase_sector(flash, addr)) { -- 2.39.2