linux/drivers/mtd
Robert Jarzmik 52c2d9aad4 mtd: docg3 fix in-middle of blocks reads
Corner case reads do not work, and return false data and
ECC. This case is typically seen in a ubifs usage, with a
read of type:
 - docg3 docg3: doc_read_oob(from=14882415, mode=1,
 data=(c30eca40:12), oob=(  (null):0))

This results in the following reads:
 - docg3 docg3: doc_read_data_area(buf=  (null), len=111)
 - docg3 docg3: doc_read_data_area(buf=c30eca40, len=12)
 - docg3 docg3: doc_read_data_area(buf=  (null), len=389)
 - docg3 docg3: doc_read_data_area(buf=  (null), len=0)
 - docg3 docg3: doc_read_data_area(buf=  (null), len=16)

If we suppose that the pages content is :
 - bytes 0 .. 111   : 0x0a
 - bytes 112 .. 255 : 0x0f
Then the returned bytes will be :
 - 111 times 0x0a (correct)
 - 0x0a 2 times and 0x0f 10 times (incorrect, should be
 0x0a,0x0f)
 - 0x0f 389 times (correct)
 - nothing
 - correct OOB

The reason seams that the first 111 bytes read ends between
the 2 docg3 planes, and that the first following read (in
the 12 bytes sequence, read of 16 bit word) returns the byte
of the rightmost plane duplicated in high and lower byte of
the word.

Fix this behaviour by ensuring that if the previous read
ended up in-between the 2 planes, there will be a first 1
byte read to get back to the beginning of leftmost plane.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-29 11:14:51 +03:00
..
chips mtd: cfi_cmdset_0002: Slight cleanup of fixup messages 2012-05-13 23:34:36 -05:00
devices mtd: docg3 fix in-middle of blocks reads 2012-05-29 11:14:51 +03:00
lpddr mtd: lpddr: replace open-coded ARRAY_SIZE with macro 2012-05-13 22:47:31 -05:00
maps mtd: fix scb2_flash build when PCI is not enabled 2012-05-13 22:52:16 -05:00
nand mtd: nand: omap: add support for hardware BCH ecc 2012-05-13 23:25:51 -05:00
onenand mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN 2012-05-13 23:14:23 -05:00
tests mtd: introduce mtd_can_have_bb helper 2012-01-09 18:26:24 +00:00
ubi Merge branch 'akpm' (Andrew's patch-bomb) 2012-04-05 15:30:34 -07:00
afs.c mtd: introduce mtd_read interface 2012-01-09 18:25:19 +00:00
ar7part.c mtd: introduce mtd_read interface 2012-01-09 18:25:19 +00:00
bcm63xxpart.c mtd: bcm63xxpart: handle Broadcom partition order 2012-05-13 22:55:03 -05:00
cmdlinepart.c mtd: cmdlinepart: fix commentary 2012-05-13 23:03:36 -05:00
ftl.c mtd: do not use mtd->sync directly 2012-01-09 18:26:21 +00:00
inftlcore.c mtd: add leading underscore to all mtd functions 2012-03-27 00:20:01 +01:00
inftlmount.c mtd: introduce mtd_block_markbad interface 2012-01-09 18:25:48 +00:00
Kconfig MTD merge for 3.4 2012-03-30 17:31:56 -07:00
Makefile mtd: maps: bcm963xx-flash: make CFE partition parsing an mtd parser 2012-01-09 18:15:31 +00:00
mtd_blkdevs.c mtd: mtdblock: call mtd_sync() only if opened for write 2012-03-27 00:11:11 +01:00
mtdblock_ro.c mtd: introduce mtd_write interface 2012-01-09 18:25:20 +00:00
mtdblock.c mtd: mtdblock: call mtd_sync() only if opened for write 2012-03-27 00:11:11 +01:00
mtdchar.c mtd: fix oops in dataflash driver 2012-05-07 20:29:50 +01:00
mtdconcat.c mtd: unify initialization of erase_info->fail_addr 2012-03-27 01:02:24 +01:00
mtdcore.c mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN 2012-05-13 23:14:23 -05:00
mtdcore.h mtd: hide parse_mtd_partitions 2011-09-11 15:02:13 +03:00
mtdoops.c mtdoops: clean-up new MTD API usage 2012-03-27 00:23:53 +01:00
mtdpart.c mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN 2012-05-13 23:14:23 -05:00
mtdsuper.c Merge git://git.infradead.org/mtd-2.6 2011-11-07 09:11:16 -08:00
mtdswap.c mtd: do not use mtd->block_markbad directly 2012-01-09 18:26:26 +00:00
nftlcore.c mtd: nftlcore: remove out-of-date and now irrelevant piece of code 2012-03-27 00:24:03 +01:00
nftlmount.c mtd: introduce mtd_block_markbad interface 2012-01-09 18:25:48 +00:00
ofpart.c mtd: ofpart: add ofoldpart alias 2011-09-11 15:02:14 +03:00
redboot.c mtd: redboot: remove useless code 2012-03-27 00:24:14 +01:00
rfd_ftl.c mtd: do not use mtd->sync directly 2012-01-09 18:26:21 +00:00
sm_ftl.c mtd: sm_ftl: fix typo in major number. 2012-03-27 01:01:26 +01:00
sm_ftl.h mtd: sm_ftl: cosmetic, use bool when possible 2010-10-25 01:33:08 +01:00
ssfdc.c mtd: introduce mtd_block_isbad interface 2012-01-09 18:25:47 +00:00