linux-toradex.git/include/linux/mtd/mtd.h, branch v3.4.73

mtd: add ecc_strength fields to mtd structs

2012-03-26T23:56:36+00:00

This adds 'ecc_strength' to struct mtd_info.  This stores the maximum number of
bit errors that can be corrected in one writesize region.

For consistency with the nand code, 'strength' is similiarly added to struct
nand_ecc_ctrl.  This stores the maximum number of bit errors that can be
corrected in one ecc step.

Signed-off-by: Mike Dunn 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: check for zero length in OTP functions

2012-03-26T23:32:29+00:00

This patch changes all the OTP functions like 'mtd_get_fact_prot_info()' and
makes them return zero immediately if the input 'len' parameter is 0. This is
not really needed currently, but most of the other functions do this, and it is
just consistent to do the same in the OTP functions.

This patch also moves the OTP functions from the header file to mtdcore.c
because they become a bit too big for being inlined.

Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: remove R/O checking duplication

2012-03-26T23:29:11+00:00

Many drivers check whether the partition is R/O and return -EROFS if yes.
Let's stop having duplicated checks and move them to the API functions
instead.

And again a bit of noise - deleted few too sparse newlines, sorry.

Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: add offset and length checks to the API function

2012-03-26T23:28:05+00:00

Add verification of the offset and length to MTD API functions and verify that
MTD device offset and length are within MTD device size.

The modified API functions are:

'mtd_erase()'
'mtd_point()'
'mtd_unpoint()'
'mtd_get_unmapped_area()'
'mtd_read()'
'mtd_write()'
'mtd_panic_write()'
'mtd_lock()'
'mtd_unlock()'
'mtd_is_locked()'
'mtd_block_isbad()'
'mtd_block_markbad()'

This patch also uninlines these functions and exports in mtdcore.c because they
are not performance-critical and do not have to be inlined.

Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: return error code from mtd_unpoint

2012-03-26T23:27:19+00:00

The 'mtd_unpoint()' API function should be able to return an error code because
it may fail if you specify incorrect offset. This patch changes this MTD API
function and amends all the drivers correspondingly.

Also return '-EOPNOTSUPP' from 'mtd_unpoint()' when the '->unpoint()' method is
undefined. We do not really need this currently, but this just makes
sense to be consistent with 'mtd_point()'.

Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: add leading underscore to all mtd functions

2012-03-26T23:20:01+00:00

This patch renames all MTD functions by adding a "_" prefix:

mtd->erase -> mtd->_erase
mtd->read_oob -> mtd->_read_oob
...

The reason is that we are re-working the MTD API and from now on it is
an error to use MTD function pointers directly - we have a corresponding
API call for every pointer. By adding a leading "_" we achieve the following:

1. Make sure we convert every direct pointer users
2. A leading "_" suggests that this interface is internal and it becomes
   less likely that people will use them directly
3. Make sure all the out-of-tree modules stop compiling and the owners
   spot the big API change and amend them.

Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

Merge tag 'for-linus-3.3' of git://git.infradead.org/~dwmw2/mtd-3.3

2012-02-04T15:17:47+00:00

 - Fix a regression in 16-bit Atmel NAND flash which was introduced in 3.1
 - Fix breakage with MTD suspend caused by the API rework
 - Fix a problem with resetting the MX28 BCH module
 - A couple of other trivial fixes

* tag 'for-linus-3.3-20120204' of git://git.infradead.org/~dwmw2/mtd-3.3:
  Revert "mtd: atmel_nand: optimize read/write buffer functions"
  mtd: fix MTD suspend
  jffs2: do not initialize variable unnecessarily
  mtd: gpmi-nand bugfix: reset the BCH module when it is not MX23
  mtd: nand: fix typo in comment

mtd: fix merge conflict resolution breakage

2012-02-01T19:10:24+00:00

This patch fixes merge conflict resolution breakage introduced by merge
d3712b9dfcf4 ("Merge tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream").

The commit changed 'mtd_can_have_bb()' function and made it always
return zero, which is incorrect.  Instead, we need it to return whether
the underlying flash device can have bad eraseblocks or not.  UBI needs
this information because it affects how it handles the underlying flash.
E.g., if the underlying flash is NOR, it cannot have bad blocks and any
write or erase error is fatal, and all we can do is to switch to R/O
mode.  We do not need to reserve a pool of good eraseblocks for bad
eraseblocks handling, and so on.

This patch also removes 'mtd_can_have_bb()' invocations from Logfs to
ensure correct Logfs behavior.

I've tested that with this patch UBI works on top of NOR and NAND
flashes emulated by mtdram and nandsim correspondingly.

This patch is based on patch from Linus Torvalds.

Signed-off-by: Artem Bityutskiy 
Acked-by: Jörn Engel 
Acked-by: Prasad Joshi 
Acked-by: Brian Norris 
Signed-off-by: Linus Torvalds

Merge tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream

2012-01-31T17:23:59+00:00

There are few important bug fixes for LogFS

* tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream:
  Logfs: Allow NULL block_isbad() methods
  logfs: Grow inode in delete path
  logfs: Free areas before calling generic_shutdown_super()
  logfs: remove useless BUG_ON
  MAINTAINERS: Add Prasad Joshi in LogFS maintiners
  logfs: Propagate page parameter to __logfs_write_inode
  logfs: set superblock shutdown flag after generic sb shutdown
  logfs: take write mutex lock during fsync and sync
  logfs: Prevent memory corruption
  logfs: update page reference count for pined pages

Fix up conflict in fs/logfs/dev_mtd.c due to semantic change in what
"mtd->block_isbad" means in commit f2933e86ad93: "Logfs: Allow NULL
block_isbad() methods" clashing with the abstraction changes in the
commits 7086c19d0742: "mtd: introduce mtd_block_isbad interface" and
d58b27ed58a3: "logfs: do not use 'mtd->block_isbad' directly".

This resolution takes the semantics from commit f2933e86ad93, and just
makes mtd_block_isbad() return zero (false) if the 'block_isbad'
function is NULL.  But that also means that now "mtd_can_have_bb()"
always returns 0.

Now, "mtd_block_markbad()" will obviously return an error if the
low-level driver doesn't support bad blocks, so this is somewhat
non-symmetric, but it actually makes sense if a NULL "block_isbad"
function is considered to mean "I assume that all my blocks are always
good".

mtd: fix MTD suspend

2012-01-30T14:23:07+00:00

Commits 3fe4bae88460869a8e553397cd9057a4ee7ca341 and
079c985e7a6f4ce60f931cebfdd5ee3c3 broke MTD suspend in 2 ways:

1. When the '->suspend' method is not present, we return -EOPNOTSUPP, but
   the callers of 'mtd_suspend()' expects 0 instead.
2. Checking of the 'mtd' parameter against NULL has been incorrectly removed
   in 'mtd_cls_suspend()'.

This patch fixes the breakages. This has been found, analyzed, reported
and tested by Rafael J. Wysocki .

Note, this patch is not needed in the stable tree because it causes a
regression introduced during the v3.3 merge window.

Reported-by: Rafael J. Wysocki 
Tested-by: Rafael J. Wysocki 
Tested-by: Russell King 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse