[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 <clumsycg@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 6188fd4ddcc0bdaef304f9e0cdea75417086ad09..6659b2275c0c6a5ce150906c25ac1d106700065a 100644 (file)
--- 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)) {