The drivers' _read() method, absent an error, returns a non-negative integer
indicating the maximum number of bit errors that were corrected in any one
region comprising an ecc step.  MTD returns -EUCLEAN if this is >=
bitflip_threshold, 0 otherwise.  If bitflip_threshold is zero, the comparison is
not made since these devices lack ECC and always return zero in the non-error
case (thanks Brian)¹.  Note that this is a subtle change to the driver
interface.

This and the preceding patches in this set were tested with ubi on top of the
nandsim and docg4 devices, running the ubi test io_basic from mtd-utils.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-March/040468.htmlSigned-off-by: NMike Dunn <mikedunn@newsguy.com>
Acked-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Acked-by: NBrian Norris <computersforpeace@gmail.com>
Ivan Djelic <ivan.djelic@parrot.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

page_read() never returns NULL, so we can remove the NULL check here.
Signed-off-by: NRyosuke Saito <raitosyo@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

clk_{un}prepare is mandatory for platforms using common clock framework. Since
this driver is used by SPEAr platform, which supports common clock framework,
add clk_{un}prepare() support for it.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

As docg3 is intolerant against reentrancy, especially
because of its weird register access (ie. a register read is
performed by a first register write), each access to the
docg3 IO space must be locked.

Lock the IO space with a mutex, shared by all chips on the
same cascade, as they all share the same IO space.
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Group floors into a common cascade structure. This will provide a common
structure to store common data to all cascaded docg3 chips, like IO
addressing, locking protection.
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

After several tries with ubifs, it appears empirically that constructor
provided figures for erase/write timeouts are underestimated. A timeout
of 100ms seems to work with a 5 years worn chip, and no timeouts occur
anymore.
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The last erase block was not accessible, as the out of bound
check was incorrectly rejecting the last block.
The read/write/erase offset checks were forbidding the usage of the
last block, because of the calculation which was considering the
byte after the last instead of the last byte.
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

phram_setup() is only called from init_phram() which is in .init.text,
so it must be in the same section to avoid a section mismatch warning.
Signed-off-by: NRyosuke Saito <raitosyo@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch adds support to configure the SPEAr SMI driver via
device-tree instead of platform_data.
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>

Additionally, after failing in mtd_device_parse_register(), the driver
unmap/free code is now executed.
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>

doc_probe_device() is only called from docg3_probe() which is in .init.text,
so it must be in the same section to avoid a section mismatch warning.
Signed-off-by: NRyosuke Saito <raitosyo@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch is based on Ville Herva's similar patch to block2mtd.

Trying to pass a parameter through the kernel command line when built-in would
crash the kernel, as phram_setup() was called so early that kmalloc() was not
functional yet.

This patch only saves the parameter string at the early boot stage, and parses
it later when init_phram() is called. The same happens in both module and
built-in cases.

With this patch, I can boot with a statically-compiled phram, and mount a
ext2 root fs from physical RAM, without the need for a initrd.

This has been tested in built-in and module cases, with and without a
parameter string.

Artem: amended comments a bit
Signed-off-by: NHervé Fache <h-fache@ti.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Flash device drivers initialize 'ecc_strength' in struct mtd_info, which is the
maximum number of bit errors that can be corrected in one writesize region.

Drivers using the nand interface intitialize 'strength' in struct nand_ecc_ctrl,
which is the maximum number of bit errors that can be corrected in one ecc step.
Nand infrastructure code translates this to 'ecc_strength'.

Also for nand drivers, the nand infrastructure code sets ecc.strength for ecc
modes NAND_ECC_SOFT, NAND_ECC_SOFT_BCH, and NAND_ECC_NONE.  It is set in the
driver for all other modes.
Signed-off-by: NMike Dunn <mikedunn@newsguy.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The read function was so far requiring the reads to be aligned on page
boundaries, and be page length multiples in size. Relieve these
constraints to ease the userspace ubifs programs runs, which read ubifs
headers of 64 bytes.

Artem: squashed a later fix from Robert Jarzmik into this patch.
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The first 3 arguments of 'mtd_device_parse_register()' are pointers,
but many callers pass '0' instead of 'NULL'. Fix this globally. Thanks
to coccinelle for making it easy to do with the following semantic patch:

 @@
 expression mtd, types, parser_data, parts, nr_parts;
 @@
 (
 -mtd_device_parse_register(mtd, 0, parser_data, parts, nr_parts)
 +mtd_device_parse_register(mtd, NULL, parser_data, parts, nr_parts)
 |
 -mtd_device_parse_register(mtd, types, 0, parts, nr_parts)
 +mtd_device_parse_register(mtd, types, NULL, parts, nr_parts)
 |
 -mtd_device_parse_register(mtd, types, parser_data, 0, nr_parts)
 +mtd_device_parse_register(mtd, types, parser_data, NULL, nr_parts)
 )
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Change the name of the mtd so that it is simpler, and is easier to
cope with by mtdparts.
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

In many places in drivers we verify for the zero length, but this is very
inconsistent across drivers. This is obviously the right thing to do, though.
This patch moves the check to the MTD API functions instead and removes a lot
of duplication.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Some MTD drivers return -EINVAL if the 'phys' parameter is not NULL, trying to
convey that they cannot return the physical address. However, this is not very
logical because they still can return the virtual address ('virt'). But some
drivers (lpddr) just ignore the 'phys' parameter instead, which is a more
logical thing to do.

Let's harmonize this and:

1. Always initialize 'virt' and 'phys' to 'NULL' in 'mtd_point()'.
2. Do not return an error if the physical address cannot be found.

So as a result, all drivers will set 'phys' to 'NULL' if it is not supported.
None of the 'mtd_point()' users use 'phys' anyway, so this should not break
anything. I guess we could also just delete this parameter later.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This header is tiny and contains only pmc551-private stuff, so it should
not live in 'include/linux' - let's just merge it with pmc551.c.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The MTD API function now zero the 'retlen' parameter before calling
the driver's method — do not do this again in drivers. This removes
duplicated '*retlen = 0' assignent from the following methods:

    'mtd_point()'
    'mtd_read()'
    'mtd_write()'
    'mtd_writev()'
    'mtd_panic_write()'
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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

We already verify that offset and length are within the MTD device size
in the MTD API functions. Let's remove the duplicated checks in drivers.
This patch only affects the following API's:

'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 adds a bit of noise by removing too sparse empty lines, but this is
not too bad.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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: 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>

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>

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>

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>

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>

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>

CONFIG_GENERIC_IO is just enough for the basic MTD stuff.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Acked-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

Fix the following build warning:

warning: (MTD_DOC2000 && MTD_DOC2001 && MTD_DOC2001PLUS) selects MTD_NAND_IDS
which has unmet direct dependencies (MTD && MTD_NAND)
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>