mtd: nand: Kill the chip->scan_bbt() hook ...

Linux commit e80eba758151 adapted for Barebox:

  None of the existing drivers are overloading the ->scan_bbt()
  method, let's get rid of it and replace calls to ->scan_bbt()
  by nand_create_bbt() ones.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd: nand: imx-bbm: use raw reading when checking for factory BBM ...

This is necessary to prevent the imx_nand_bbm command to bail out
on ECC errors which leaves the device without BBT.

Also simplify buffer management: Use on-stack buffer instead of malloc.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

stdio: rename getc to getchar ...

The function we have implemented as getc has the semantics of the
standard function getchar, so rename it accorgingly.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

trivial: s/flasg/flash/ ...

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: harmonize in-barebox documentation ...

This patch does probably too much, but it's hard (and very
cumbersome/time consuming) to break it out. What is does is this:

* each command has one short description, e.g. "list MUX configuration"
* made sure the short descriptions start lowercase
* each command has one usage. That string contains just the
  options, e.g. "[-npn]". It's not part of the long help text.
* that is, it doesn't say "[OPTIONS]" anymore, every usable option
  is listed by character in this (short) option string (the long
  description is in the long help text, as before)
* help texts have been reworked, to make them
  - sometimes smaller
  - sometimes describe the options better
  - more often present themselves in a nicer format
* all long help texts are now created with BUSYBOX_CMD_HELP_
  macros, no more 'static const __maybe_unused char cmd_foobar_help[]'
* made sure the long help texts starts uppercase
* because cmdtp->name and cmdtp->opts together provide the new usage,
  all "Usage: foobar" texts have been removed from the long help texts
* BUSYBOX_CMD_HELP_TEXT() provides the trailing newline by itself, this
  is nicer in the source code
* BUSYBOX_CMD_HELP_OPT() provides the trailing newline by itself
* made sure no line gets longer than 77 characters
* delibertely renamed cmdtp->usage, so that we can get compile-time
  errors (e.g. in out-of-tree modules that use register_command()
* the 'help' command can now always emit the usage, even without
  compiled long help texts
* 'help -v' gives a list of commands with their short description, this
  is similar like the old "help" command before my patchset
* 'help -a' gives out help of all commands

Signed-off-by: Holger Schurig <holgerschurig@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: group 'help' output ...

The old output of "help" was just producing a long list, that usually
scrolled of the screen (even on a X11 terminal). This list is more
compact, and also sorted by groups.

The old output format (plus grouping) is now available with 'help -v'.

Example:

   Information commands:
     ?, devinfo, help, iomem, meminfo, version
   Boot commands:
     boot, bootm, go, loadb, loads, loadx, loady, saves, uimage
   ...

Signed-off-by: Holger Schurig <holgerschurig@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

NAND: imx: Fix memory leak ...

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd: nand: Add command to generate a flash BBT ...

With 2k NAND flashes the data layout in memory is not what is
written on the flash device. This leads to the result that the
factory provided bad block markers are not recognized correctly.

To preserve the factory bad block information the i.MX NAND driver
will not scan for the bad blocks itself when there is no flash based
bbt available, because the mtd layer would do so based on wrong
information. Instead, a new command is introduced which allows to
manually create a flash bbt based on the correct information.

As this command is tightly coupled to mtd and the i.MX NAND driver
the command is placed under drivers/mtd/nand/ instead of commands/
where a command normally belongs to.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>