Currently, the flash-based BBT implementation writes bad block data only
to its flash-based table and not to the OOB marker area. Then, as new bad
blocks are marked over time, the OOB markers become incomplete and the
flash-based table becomes the only source of current bad block
information. This becomes an obvious problem when, for example:

 * bootloader cannot read the flash-based BBT format
 * BBT is corrupted and the flash must be rescanned for bad
   blocks; we want to remember bad blocks that were marked from Linux

So to keep the bad block markers in sync with the flash-based BBT, this
patch changes the default so that we write bad block markers to the proper
OOB area on each block in addition to flash-based BBT. Comments are
updated, expanded, and/or relocated as necessary.

The new flash-based BBT procedure for marking bad blocks:
 (1) erase the affected block, to allow OOB marker to be written cleanly
 (2) update in-memory BBT
 (3) write bad block marker to OOB area of affected block
 (4) update flash-based BBT
Note that we retain the first error encountered in (3) or (4), finish the
procedures, and dump the error in the end.

This should handle power cuts gracefully enough. (1) and (2) are mostly
harmless (note that (1) will not erase an already-recognized bad block).
The OOB and BBT may be "out of sync" if we experience power loss bewteen
(3) and (4), but we can reasonably expect that on next boot, subsequent
I/O operations will discover that the block should be marked bad again,
thus re-syncing the OOB and BBT.

Note that this is a change from the previous default flash-based BBT
behavior. If your system cannot support writing bad block markers to OOB,
use the new NAND_BBT_NO_OOB_BBM option (in combination with
NAND_BBT_USE_FLASH and NAND_BBT_NO_OOB).
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

We do not need to invoke 'mtd_can_have_bb()' before invoking
'mtd_block_isbad()' because the latter already handles the case when the MTD
device does not support bad blocks.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Let's remove useless 'mtd_can_have_bb()' function invocations.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The main 'mtd_block_markbad()' function returns -EOPNOTSUPP if the
'->block_markbad' method is undefined, and mtdconcat should do the same.
Fix this by simply removing the 'mtd_can_have_bb()' because it is  not
really necessary. It could be treated as an optimization, but this function is
expected to be used so rarely that it does not matter.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set writebufsize to the flash page size because it is the maximum amount of
data it writes at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set writebufsize to the flash page size because it is the maximum amount of
data it writes at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: NStefan Roese <sr@denx.de>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set writebufsize to 4 because this drivers writes at max 4 bytes at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set it to be equivalent to mtd->writesize because this is the maximum amount
of data the driver writes at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Cc: stable@kernel.org [3.2+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set it to be equivalent to mtd->writesize because this is the maximum amount
of data the driver writes at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set it to be equivalent to mtd->writesize because this is the maximum amount
of data the driver writes at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set it to be equivalent to mtd->writesize because this is the maximum amount
of data the driver writes at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

However, we forgot to set this parameter for block2mtd. Set it to PAGE_SIZE
because this is actually the amount of data we write at a time.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: NJoern Engel <joern@lazybastard.org>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Per call site OOM messages are unnecessary.
k.alloc and v.alloc failures use dump_stack().
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Gcc complains here:
drivers/mtd/nand/docg4.c: In function ‘probe_docg4’:
drivers/mtd/nand/docg4.c:1277:4: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘resource_size_t’ [-Wformat]
drivers/mtd/nand/docg4.c:1277:4: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 4 has type ‘resource_size_t’ [-Wformat]

We have a standard way of printing these using a format string
extension.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This has been moved from .options to .bbt_options meanwhile. So, it
currently checks for something totally different (NAND_OWN_BUFFERS) and
decides according to that.

Artem Bityutskiy: the options were moved in
a40f7341 mtd: nand: consolidate redundant flash-based BBT flags

Artem Bityutskiy: CCing -stable
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [3.2+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Using UBI on m25p80 can give messages like:

    UBI error: io_init: bad write buffer size 0 for 1 min. I/O unit

We need to initialize writebufsize; I think "page_size" is the correct
"bufsize", although I'm not sure. Comments?
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

We don't need to to check for mtd->resume before calling mtd_resume().
mtd_resume() should take care of that.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Correct spelling "scaning" to scanning" in
fs/jffs2/scan.c
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

There were a few instances of the old MTD interface remaining for JFFS2. We
fix one error that shows up (only when CONFIG_JFFS2_FS_WRITEBUFFER is not
defined) like this:

  fs/jffs2/read.c: In function 'jffs2_read_dnode':
  fs/jffs2/read.c:36:8: error: 'struct mtd_info' has no member named 'read'
  fs/jffs2/read.c:112:8: error: 'struct mtd_info' has no member named 'read'
  ...

We also simply remove two macros that are not in use, were not updated to
the new MTD interface, and don't even utilize the old interface properly.
(That means they weren't used since commit 8593fbc6, year 2006; almost 6
years ago, for those who don't want to do the math)
Reported-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Acked-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

We have changed the MTD API and now ROMFS should use 'mtd_read()' instead
of mtd->read().
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Commit 10934478 did not remove now useless
"if (mtd->point)" check mistakingly - let's kill it now.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch adds a driver for the M-Sys / Sandisk diskonchip G4 nand flash found
in various smartphones and PDAs, among them the Palm Treo680, HTC Prophet and
Wizard, Toshiba Portege G900, Asus P526, and O2 XDA Zinc.  It was tested on the
Treo 680, but should work generically.

Since v3, this patch adds power management functions, a scan of the factory bad
block table during initialization, several fixes, and more extensive testing.
Also, the platform data header file, which only contained partitioning
information, was removed.  Command-line partitioning can be used, at least until
an mtd parser is written for the saftl format with which these chips are
shipped.
Signed-off-by: NMike Dunn <mikedunn@newsguy.com>
Reviewed-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NStefan Roese <sr@denx.de>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch converts the drivers in drivers/mtd/* to use the
module_spi_driver() macro which makes the code smaller and a bit simpler.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

As nand_default_block_markbad() is becoming more complex, it helps to
have code appear only in its relevant codepath(s). Here, the calculation
of `ofs' based on NAND_BBT_SCANLASTPAGE is only useful on paths where we
write bad block markers to OOB. We move the condition/calculation closer
to the `write' operation and update the comment to more correctly
describe the operation.

The variable `wr_ofs' is also used to help isolate our calculation of
the "write" offset from the usage of `ofs' to represent the eraseblock
offset. This will become useful when we reorder operations in the next
patch.

This patch should make no functional change.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The mtdoops usage instructions found in Kconfig have been incorrect
since:

    commit 2e386e4b
    mtd: mtdoops: refactor as a kmsg_dumper

mtdoops no longer uses a console. Now, if you build it into your kernel,
you add something like the following to your command line to select
partition X as your logging partition:

    mtdoops.mtddev=X

Anyway, it seems better to leave the documentation out of Kconfig.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

/*
 * This is here for documentation purposes only - until these people
 * submit their machine types.  It will be gone January 2005.
 */

It's now seven years after that date, so let's remove this.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Commit c4a9f88d ([MTD] [NOR] fix ctrl-alt-del can't reboot for
intel flash bug) interferes with this work-around, causing MTD to
issue this warning:

	Flash device refused suspend due to active operation (state 0)

The commit makes our work-around in the map driver unnecessary, so
let's remove it.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Driver must cleanup all held resources during remove. It wasn't
releasing requested memory region.
Signed-off-by: NShiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: NStefan Roese <sr@denx.de>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

SPEAr platforms (spear3xx/spear6xx/spear13xx) provide SMI (Serial Memory
Interface) controller to access serial NOR flash. SMI provides a simple
interface for SPI/serial NOR flashes and has certain inbuilt commands
and features to support these flashes easily. It also makes it possible
to map an address range in order to directly access (read/write) the SNOR
over address bus. This patch intends to provide serial nor driver support
for spear platforms which are accessed through SMI.
Signed-off-by: NShiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NStefan Roese <sr@denx.de>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The description for badblockbits is incorrect. I think someone just made
up a false description on the spot to satisfy some kerneldoc warning.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

It seems that we have developed a bad-block-marking "feature" out of
pure laziness:

  "We write two bytes per location, so we dont have to mess with 16 bit
  access."

It's relatively simple to write a 1 byte at a time on x8 devices and 2
bytes at a time on x16 devices, so let's do it.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

nand_block_bad() doesn't check the correct pages when
NAND_BBT_SCAN2NDPAGE is enabled. It should scan both the OOB region of
both the 1st and 2nd page of each block.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Many NAND flash systems (especially those with MLC NAND) cannot be
reliably written twice in a row. For instance, when marking a bad block,
the block may already have data written to it, and so we should attempt
to erase the block before writing a bad block marker to its OOB region.

We can ignore erase failures, since the block may be bad such that it
cannot be erased properly; we still attempt to write zeros to its spare
area.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Add missing iounmap in error handling code, in a case where the function
already preforms iounmap on some other execution path.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e;
statement S,S1;
int ret;
@@
e = \(ioremap\|ioremap_nocache\)(...)
... when != iounmap(e)
if (<+...e...+>) S
... when any
    when != iounmap(e)
*if (...)
   { ... when != iounmap(e)
     return ...; }
... when any
iounmap(e);
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Fix the following build warning:

drivers/mtd/mtdcore.c: In function ‘mtd_release’:
drivers/mtd/mtdcore.c:110: warning: unused variable ‘mtd’

This happens when neither CONFIG_MTD_CHAR nor CONFIG_MTD_CHAR_MODULE are defined.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Because it is useless to call it if the device is opened in R/O mode, and also
harmful: on CFI NOR flash it may block for long time waiting for erase
operations to complete is another partition with a R/W file-system on this
chip.

Artem Bityutskiy: write commit message, amend the patch to match the latest
tree (we use mtd_sync(), not mtd->sync() nowadays).
Signed-off-by: NAlexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Since "length" is a u32, the error handling below didn't work when
fixup_pmc551() returns -ENODEV.

	if ((length = fixup_pmc551(PCI_Device)) <= 0)

This patch changes both the type of "length" and the return type of
fixup_pmc551() to int.
Signed-off-by: NXi Wang <xi.wang@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>