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| author | Sascha Hauer <s.hauer@pengutronix.de> | 2012-08-02 12:01:05 +0200 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2012-08-03 19:32:07 +0200 |
| commit | 85f4fe32cfccf06223d55dc5751e0c644b119a9b (patch) | |
| tree | 29ab6438c1717768c2a4a9d3ef3cf255f5e1a9ab /drivers/mtd | |
| parent | 5a693051df54d9c690d141095089449346e748e5 (diff) | |
| download | barebox-85f4fe32cfccf06223d55dc5751e0c644b119a9b.tar.gz barebox-85f4fe32cfccf06223d55dc5751e0c644b119a9b.tar.xz | |
mtd nand: implement buswidth detection
This introduces a new NAND_BUSWIDTH_AUTO flag which can be used
to automatically detect the nand buswidth. The id is always read
in 8bit mode. An additional callback is needed to switch the nand
controller into 16bit mode.
This currently depends on a safe read_byte (always) and read_buf
(for onfi-only flashes) callback. It has been tested on OMAP, but
is not something that generally works. For this reason the existence
of the set_buswidth callback is used to determine whether we are
able to do autodetection or not.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/nand/nand_base.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index a5bf757e47..37e57b32ce 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -1000,7 +1000,7 @@ static void nand_set_defaults(struct nand_chip *chip, int busw) if (!chip->select_chip) chip->select_chip = nand_select_chip; - if (!chip->read_byte) + if (!chip->read_byte || chip->read_byte == nand_read_byte) chip->read_byte = busw ? nand_read_byte16 : nand_read_byte; if (!chip->read_word) chip->read_word = nand_read_word; @@ -1009,12 +1009,12 @@ static void nand_set_defaults(struct nand_chip *chip, int busw) #ifdef CONFIG_MTD_WRITE if (!chip->block_markbad) chip->block_markbad = nand_default_block_markbad; - if (!chip->write_buf) + if (!chip->write_buf || chip->write_buf == nand_write_buf) chip->write_buf = busw ? nand_write_buf16 : nand_write_buf; #endif - if (!chip->read_buf) + if (!chip->read_buf || chip->read_buf == nand_read_buf) chip->read_buf = busw ? nand_read_buf16 : nand_read_buf; - if (!chip->verify_buf) + if (!chip->verify_buf || chip->verify_buf == nand_verify_buf) chip->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf; #ifdef CONFIG_NAND_BBT if (!chip->scan_bbt) @@ -1258,6 +1258,13 @@ ident_done: break; } + if (chip->options & NAND_BUSWIDTH_AUTO) { + chip->options |= busw; + nand_set_defaults(chip, busw); + if (chip->set_buswidth) + chip->set_buswidth(mtd, chip, busw); + } + /* * Check, if buswidth is correct. Hardware drivers should set * chip correct ! @@ -1326,6 +1333,11 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips) struct nand_chip *chip = mtd->priv; struct nand_flash_dev *type; + if (chip->options & NAND_BUSWIDTH_AUTO && !chip->set_buswidth) { + printk(KERN_ERR "buswidth detection but no buswidth callback\n"); + return -EINVAL; + } + /* Get buswidth to select the correct functions */ busw = chip->options & NAND_BUSWIDTH_16; /* Set the default functions */ |