If a write to one time programmable memory (OTP) hits the end of this
memory area, no more data can be written. The count variable in
mtdchar_write() in drivers/mtd/mtdchar.c is not decreased anymore.
We are trapped in the loop forever, mtdchar_write() will never return
in this case.

The desired behavior of a write in such a case is described in [1]:
- Try to write as much data as possible, truncate the write to fit into
  the available memory and return the number of bytes that actually
  have been written.
- If no data could be written at all, return -ENOSPC.

This patch fixes the behavior of OTP write if there is not enough space
for all data:

1) mtd_write_user_prot_reg() in drivers/mtd/mtdcore.c is modified to
   return -ENOSPC if no data could be written at all.
2) mtdchar_write() is modified to handle -ENOSPC correctly. Exit if a
   write returned -ENOSPC and yield the correct return value, either
   then number of bytes that could be written, or -ENOSPC, if no data
   could be written at all.

Furthermore the patch harmonizes the behavior of the OTP memory write
in drivers/mtd/devices/mtd_dataflash.c with the other implementations
and the requirements from [1]. Instead of returning -EINVAL if the data
does not fit into the OTP memory, we try to write as much data as
possible/truncate the write.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/write.htmlSigned-off-by: NChristian Riesch <christian.riesch@omicron.at>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

fixme applied : check device size is a multiple of erasesize.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Crash detected on sam5d35 and its pmecc nand ecc controller.

The problem was a call to chip->ecc.hwctl from nand_write_subpage_hwecc
(nand_base.c) when we write a sub page.
chip->ecc.hwctl function is not set when we are using PMECC controller.
As a workaround, set NAND_NO_SUBPAGE_WRITE for PMECC controller in
order to disable sub page access in nand_write_page.
Signed-off-by: NHerve Codina <Herve.CODINA@celad.com>
Acked-by: NJosh Wu <josh.wu@atmel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

1) Why add the subpage read support?
  The page size of the nand chip becomes larger and larger, the imx6 has to
  supports the 16K page or even bigger page. But sometimes, the upper layer only
  needs a small part of the page, such as 512 bytes or less.

  For example, ubiattach may only read 64 bytes per page.

2) We only enable the subpage read support when it meets the conditions:
   <1> the chip is imx6 (or later chips) which can supports large nand page.
   <2> the size of ECC parity is byte aligned.
       If the size of ECC parity is not byte aligned, the calling of NAND_CMD_RNDOUT
       will fail.

3) What does this patch do?
   This patch will fake a virtual small page for the subpage read, and call the
   gpmi_ecc_read_page() to do the real work.

   In order to fake a virtual small page, the patch changes the BCH registers and
   the bch_geometry{}. After the subpage read finished, we will restore them back.

4) Performace:
    4.1) Tested with Toshiba TC58NVG2S0F(4096 + 224) with the following command:
         #ubiattach /dev/ubi_ctrl -m 4

       The detail information of /dev/mtd4 shows below:
       --------------------------------------------------------------
       #mtdinfo /dev/mtd4
        mtd4
        Name:                           test
        Type:                           nand
        Eraseblock size:                262144 bytes, 256.0 KiB
        Amount of eraseblocks:          1856 (486539264 bytes, 464.0 MiB)
        Minimum input/output unit size: 4096 bytes
        Sub-page size:                  4096 bytes
        OOB size:                       224 bytes
        Character device major/minor:   90:8
        Bad blocks are allowed:         true
        Device is writable:             true
       --------------------------------------------------------------

    4.2) Before this patch:
       --------------------------------------------------------------
       [   94.530495] UBI: attaching mtd4 to ubi0
       [   98.928850] UBI: scanning is finished
       [   98.953594] UBI: attached mtd4 (name "test", size 464 MiB) to ubi0
       [   98.958562] UBI: PEB size: 262144 bytes (256 KiB), LEB size: 253952 bytes
       [   98.964076] UBI: min./max. I/O unit sizes: 4096/4096, sub-page size 4096
       [   98.969518] UBI: VID header offset: 4096 (aligned 4096), data offset: 8192
       [   98.975128] UBI: good PEBs: 1856, bad PEBs: 0, corrupted PEBs: 0
       [   98.979843] UBI: user volume: 1, internal volumes: 1, max. volumes count: 128
       [   98.985878] UBI: max/mean erase counter: 2/1, WL threshold: 4096, image sequence number: 2024916145
       [   98.993635] UBI: available PEBs: 0, total reserved PEBs: 1856, PEBs reserved for bad PEB handling: 40
       [   99.001807] UBI: background thread "ubi_bgt0d" started, PID 831
       --------------------------------------------------------------
       The attach time is about 98.9 - 94.5 = 4.4s

    4.3) After this patch:
       --------------------------------------------------------------
       [  286.464906] UBI: attaching mtd4 to ubi0
       [  289.186129] UBI: scanning is finished
       [  289.211416] UBI: attached mtd4 (name "test", size 464 MiB) to ubi0
       [  289.216360] UBI: PEB size: 262144 bytes (256 KiB), LEB size: 253952 bytes
       [  289.221858] UBI: min./max. I/O unit sizes: 4096/4096, sub-page size 4096
       [  289.227293] UBI: VID header offset: 4096 (aligned 4096), data offset: 8192
       [  289.232878] UBI: good PEBs: 1856, bad PEBs: 0, corrupted PEBs: 0
       [  289.237628] UBI: user volume: 0, internal volumes: 1, max. volumes count: 128
       [  289.243553] UBI: max/mean erase counter: 1/1, WL threshold: 4096, image sequence number: 2024916145
       [  289.251348] UBI: available PEBs: 1812, total reserved PEBs: 44, PEBs reserved for bad PEB handling: 40
       [  289.259417] UBI: background thread "ubi_bgt0d" started, PID 847
       --------------------------------------------------------------
       The attach time is about 289.18 - 286.46 = 2.7s

     4.4) The conclusion:
       We achieve (4.4 - 2.7) / 4.4 = 38.6% faster in the ubiattach.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The nfc_geo->payload_size is equal to the mtd->writesize now,
use the nfc_geo->payload_size to replace the mtd->writesize.

This patch makes preparation for the gpmi's subpage read support.
In the subpage support, the nfc_geo->payload_size maybe smaller then
the mtd->writesize.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Add the "page" argument for the read_subpage hook. With this argument,
the implementation of this hook could prints out more accurate information
for debugging.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The nand_get_flash_type parameter "busw" input value is not used by any
branch, and it is updated before use it in the function, so remove it,
define the "busw" as an internal variable.
Signed-off-by: NCai Zhiyong <caizhiyong@huawei.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The actual ECC strength used to select the ECC scheme is 'ecc_strength'.
Use it in the error message.
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

This macro is not used so it's safe to remove it.
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Home routers based on SoCs like BCM53010 (AKA BCM4708) use flashes
which can be nicely partitioned with bcm47xxpart. Header bcm47xx_nvram.h
is not available on bcm53xx, so don't include it.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Our code parsing "trx" header registers few partitions at once (in one
loop iteration). Add extra check in that place.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Up to now mtd-ram devices described in device trees were only accessible
if mtd-flash or mtd-rom were also configured at linux configuration
time, because MTD_PHYSMAP_OF was only available if (MTD_CFI ||
MTD_JEDECPROBE || MTD_ROM).  Allow MTD_PHYSMAP_OF selection also
when only MTD_RAM is set.
Signed-off-by: NPhilippe De Muyter <phdm@macqel.be>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Acked-by: NMarek Vasut <marex@denx.de>

Signed-off-by: NChristian Riesch <christian.riesch@omicron.at>
Cc: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

There is no point in displaying the TS5500-specific driver entries if
TS5500 board support itself isn't enabled.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Instead of writing to "nand->reg + REG_FMICSR" we write to "REG_FMICSR"
which is NULL and not a valid register.

Fixes: 8bff82cb ('mtd: add nand support for w90p910 (v2)')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Check the chip->jedec_version, and print out the right information
for JEDEC compliant NAND.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

This patch adds the parsing code for the JEDEC compliant NAND.

Since we need the 0x40 as the column address, this patch also
makes the NAND_CMD_PARAM to use the 8-bit address only.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Check the return value from platform_get_irq() and propagate it in the case of
error.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

"rc" is an error code here, no need to check it a second time.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

PIO fall back is not an issue, so don't make this much noise.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Signed-off-by: NYusuke Goda <yusuke.goda.sx@renesas.com>
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGeert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NPekon Gupta <pekon@ti.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The ELM driver incorrectly reagard any non-zero return value from
pm_runtime_get_sync as an error, but it may return 1 if the device
was already active. Fix to only error when return value is negative.
Signed-off-by: NStefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

read_buf is called in place of write_buf in the
nand_write_page_raw_syndrome function.
Signed-off-by: NBoris BREZILLON <b.brezillon.dev@gmail.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

On archs like S390 or um this driver cannot build nor work.
Make it depend on HAS_IOMEM and HAS_DMA to bypass build failures.

drivers/built-in.o: In function `flctl_probe':
drivers/mtd/nand/sh_flctl.c:1097: undefined reference to `devm_ioremap_resource'
drivers/built-in.o: In function `flctl_dma_fifo0_transfer':
drivers/mtd/nand/sh_flctl.c:368: undefined reference to `dma_map_single'
drivers/mtd/nand/sh_flctl.c:407: undefined reference to `dma_unmap_single'
Signed-off-by: NRichard Weinberger <richard@nod.at>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

For slightly better readability.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Use a repeated read_byte() instead of read_buf(), since for x16 buswidth
devices, we need to avoid the upper I/O[16:9] bits. See the following
commit for reference:

commit 05f78359
Author: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Date:   Thu Dec 5 22:22:04 2013 +0100

    mtd: nand: don't use {read,write}_buf for 8-bit transfers

Now, I think that all barriers to probing ONFI on x16 devices are
removed, so remove the check from nand_flash_detect_onfi().

Tested on 8-bit ONFI NAND (Micron MT29F32G08CBADAWP).
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Tested-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-By: NPekon Gupta <pekon@ti.com>

The NAND command helpers tend to automatically shift the column address
for x16 bus devices, since most commands expect a word address, not a
byte address. The Read ID command, however, expects an 8-bit address
(i.e., 0x00, 0x20, or 0x40 should not be translated to 0x00, 0x10, or
0x20).

This fixes the column address for a few drivers which imitate the
nand_base defaults. Note that I don't touch sh_flctl.c, since it already
handles this problem slightly differently (note its comment "READID is
always performed using an 8-bit bus").

I have not tested this patch, as I only have x8 parts up for testing at
this point. Hopefully that can change soon...
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Tested-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-By: NPekon Gupta <pekon@ti.com>

The datasheet does not tell us how to parse out the ID data,
so handle it as a full ID nand.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

The patch converts the arrays to buffer pointers for nand_buffers{}.

The cafe_nand.c is the only NAND_OWN_BUFFERS user which allocates
nand_buffers{} itself.

This patch disables the DMA for nand_scan_ident, and restores the DMA
status after we finish the nand_scan_ident. This way, we can get page
size and OOB size and use them to allocate cafe->dmabuf.

Since the cafe_nand.c uses the NAND_ECC_HW_SYNDROME ECC mode, we do not
allocate the buffers for @ecccalc and @ecccode.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
[Brian: dropped one incorrect hunk]
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>