drivers/mtd/maps/physmap_of.c: In function ‘of_flash_probe’:
drivers/mtd/maps/physmap_of.c:165:16: warning: variable ‘p’ set but not used [-Wunused-but-set-variable]

This could be a problem if the 'reg' property is not set, since that
means 'count' will be uninitialized.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>

In order to support device tree probing of Versatile NOR flash
chips, there must be a way to add the VPP (write protection)
enable/disable callback. The register in question is in the
system controllers of these machines. Apart from this quirk,
the ARM flash chips are standard CFI flash chips from various
vendors.

Additionally, the Integrator/AP require you to set up the external
bus interface (EBI) to allow writes to the chip select where the
flash memory is connected.

Solve this by looking for the arm,versatile-flash compatible
string in the flash device tree node. In the driver,
add a special hook to check for the various Versatile syscons and
register a callback for .set_vpp() if this compatible is present.

Provide a special Kconfig entry for the addon hook so it will
not be compiled in if the Versatile boards are not supported.
Stubs in the header file make sure the impact will be zero on
other platforms. (Compilers optimze this out.)

With this patch, a large slew of ARM board file code can be
removed.

Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

If there is more than one map region for this device, then the
concatenated MTD will not have a parent device assigned to it -- only
the sub-devices (which are not actually registered with the framework)
will have their parents assigned. Let's assign the concatenated device
correctly.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>

We should assign the MTD dev.of_node instead of the parser data field.
This gets us the equivalent partition parser behavior with fewer special
fields and parameter passing.

Also convert several of these to mtd_device_register(), since we don't
need the 2nd and 3rd parameters anymore.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Owner is automatically set by mtdcore. Make use of that.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

static analysis by smatch caught the following error:

drivers/mtd/maps/physmap_of.c:135 of_get_probes()
   error: potential null dereference 'res'.  (kzalloc returns null)

Check for failed kzalloc and return -ENOMEM in of_flash_probe if
this occurs.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

Previously, when probing a CFI chip which was write-protected at the
hardware level, the probe would fail due to the fact it could not put
the chip into QUERY mode. This would result in no MTD devices being
created.

Add a fallback to probe using the map_rom driver if the user-selected
probe fails.

Signed-off-by: Joe Schultz <jschultz@xes-inc.com>
Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

Pull MTD updates from Brian Norris:
 "Summary:
   - Add device tree support for DoC3

   - SPI NOR:
        Refactoring, for better layering between spi-nor.c and its
        driver users (e.g., m25p80.c)

        New flash device support

        Support 6-byte ID strings

   - NAND:
        New NAND driver for Allwinner SoC's (sunxi)

        GPMI NAND: add support for raw (no ECC) access, for testing
        purposes

        Add ATO manufacturer ID

        A few odd driver fixes

   - MTD tests:
        Allow testers to compensate for OOB bitflips in oobtest

        Fix a torturetest regression

   - nandsim: Support longer ID byte strings

  And more"

* tag 'for-linus-20141215' of git://git.infradead.org/linux-mtd: (63 commits)
  mtd: tests: abort torturetest on erase errors
  mtd: physmap_of: fix potential NULL dereference
  mtd: spi-nor: allow NULL as chip name and try to auto detect it
  mtd: nand: gpmi: add raw oob access functions
  mtd: nand: gpmi: add proper raw access support
  mtd: nand: gpmi: add gpmi_copy_bits function
  mtd: spi-nor: factor out write_enable() for erase commands
  mtd: spi-nor: add support for s25fl128s
  mtd: spi-nor: remove the jedec_id/ext_id
  mtd: spi-nor: add id/id_len for flash_info{}
  mtd: nand: correct the comment of function nand_block_isreserved()
  jffs2: Drop bogus if in comment
  mtd: atmel_nand: replace memcpy32_toio/memcpy32_fromio with memcpy
  mtd: cafe_nand: drop duplicate .write_page implementation
  mtd: m25p80: Add support for serial flash Spansion S25FL132K
  MTD: m25p80: fix inconsistency in m25p_ids compared to spi_nor_ids
  mtd: spi-nor: improve wait-till-ready timeout loop
  mtd: delete unnecessary checks before two function calls
  mtd: nand: omap: Fix NAND enumeration on 3430 LDP
  mtd: nand: add ATO manufacturer info
  ...

On device remove, when testing the cmtd field of an of_flash
struct to decide whether it is a concatenated device or not,
we get a false positive on cmtd == NULL, and dereference it
subsequently. This may occur if of_flash_remove() is called
from the cleanup path of of_flash_probe().

Instead, test for NULL first, and only then perform the test
for a concatenated device.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>