From 33efde5ecac91ab118ff00b95a181fd6d75f8645 Mon Sep 17 00:00:00 2001 From: Karl Beldan Date: Mon, 15 Sep 2008 16:08:03 +0200 Subject: [PATCH] NAND: Reset chip on power-up Some chips require a RESET after power-up (e.g. Micron MT29FxGxxxxx). The first command sent is NAND_CMD_READID. Issue a NAND_CMD_RESET in nand_scan_ident before reading the device id. Tested with an MT29F4G08AAC. Signed-off-by: Karl Beldan Signed-off-by: Scott Wood --- drivers/mtd/nand/nand_base.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 4069ab1278..ba05b762ed 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -2450,6 +2450,12 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, /* Select the device */ chip->select_chip(mtd, 0); + /* + * Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx) + * after power-up + */ + chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); + /* Send the command for reading device ID */ chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1); @@ -2620,6 +2626,8 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips) /* Check for a chip array */ for (i = 1; i < maxchips; i++) { chip->select_chip(mtd, i); + /* See comment in nand_get_flash_type for reset */ + chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); /* Send the command for reading device ID */ chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1); /* Read manufacturer and device IDs */ -- 2.39.5