Those hooks have been overloaded by some drivers for bad reasons:
either the driver was not fitting in the NAND framework and should
have been an MTD driver (docg4), or it was not properly implementing
the OOB read/write request or had a weird layout where BBM are trashed.
In any case, we should discourage people from overloading those
methods and encourage them to fix their driver instead.

Move the ->block_{bad,markbad}() hooks to the nand_legacy struct to
make it clear.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Those hooks have been replaced by ->exec_op(). Move them to the
nand_legacy struct.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Those hooks have been replaced by ->exec_op(). Move them to the
nand_legacy struct.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

All those hooks have been replaced by ->exec_op(). Move them to the
nand_legacy struct.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

We regularly have new NAND controller drivers that are making use of
fields/hooks that we want to get rid of but can't because of all the
legacy drivers that we might break if we do.

So, instead of removing those fields/hooks, let's move them to a
sub-struct which is clearly documented as deprecated.

We start with the ->IO_ADDR_{R,W] fields.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

There's no good reason to make maxchips a signed integer, since only
positive values are valid. Make it an unsigned int.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the nand_erase_nand() helper.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the nand_xxx_bbt() helpers.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->setup_data_interface() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->setup_read_retry() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->{get,set}_features() hooks.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->erase() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->waitfunc() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->cmdfunc() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->dev_ready() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->cmd_ctrl() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all chip->block_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle the chip->select_chip() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all chip->write_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all chip->read_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all ecc->write_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

Let's tackle all ecc->read_xxx() hooks at once.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Acked-by: NStefan Agner <stefan@agner.ch>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one.

Now is ecc->correct()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one.

Now is ecc->calculate()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one.

Now is ecc->hwctl()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers to
take a nand_chip object instead of an mtd_info one.

Now is nand_wait_ready()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers to
take a nand_chip object instead of an mtd_info one.

Now is nand_release()'s turn.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers to take
a nand_chip object instead of an mtd_info one.

We start with nand_scan().
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Let's make the raw NAND API consistent by patching all helpers and
hooks to take a nand_chip object instead of an mtd_info one or
remove the mtd_info object when both are passed.

In order to do that, we first need to update the platform_nand_ctrl
hooks to take a nand_chip object instead of an mtd_info.

We add temporary plat_nand_xxx() wrappers to the do the mtd -> chip
conversion, but those will be dropped when patching nand_chip hooks to
take a nand_chip object.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: NAlexander Sverdlin <alexander.sverdlin@gmail.com>
Acked-by: NAlexander Sverdlin <alexander.sverdlin@gmail.com>
Acked-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Acked-by: NKrzysztof Halasa <khalasa@piap.pl>
Acked-by: NPaul Burton <paul.burton@mips.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Commit c120e75e ("mtd: nand: use read_oob() instead of cmdfunc()
for bad block check") removed this only user of the ->read_word()
method but kept the hook in place. Remove it now.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Now that it is possible to do dynamic allocations during the
identification phase, convert the onfi_params structure (which is only
needed with ONFI compliant chips) into a pointer that will be allocated
only if needed.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>

Commit 59b356ff ("mtd: m25p80: restore the status of SPI flash when
exiting") is the latest from a long history of attempts to add reboot
handling to handle stateful addressing modes on SPI flash. Some prior
mostly-related discussions:

http://lists.infradead.org/pipermail/linux-mtd/2013-March/046343.html
[PATCH 1/3] mtd: m25p80: utilize dedicated 4-byte addressing commands

http://lists.infradead.org/pipermail/barebox/2014-September/020682.html
[RFC] MTD m25p80 3-byte addressing and boot problem

http://lists.infradead.org/pipermail/linux-mtd/2015-February/057683.html
[PATCH 2/2] m25p80: if supported put chip to deep power down if not used

Previously, attempts to add reboot-time software reset handling were
rejected, but the latest attempt was not.

Quick summary of the problem:
Some systems (e.g., boot ROM or bootloader) assume that they can read
initial boot code from their SPI flash using 3-byte addressing. If the
flash is left in 4-byte mode after reset, these systems won't boot. The
above patch provided a shutdown/remove hook to attempt to reset the
addressing mode before we reboot. Notably, this patch misses out on
huge classes of unexpected reboots (e.g., crashes, watchdog resets).

Unfortunately, it is essentially impossible to solve this problem 100%:
if your system doesn't know how to reset the SPI flash to power-on
defaults at initialization time, no amount of software can really rescue
you -- there will always be a chance of some unexpected reset that
leaves your flash in an addressing mode that your boot sequence didn't
expect.

While it is not directly harmful to perform hacks like the
aforementioned commit on all 4-byte addressing flash, a
properly-designed system should not need the hack -- and in fact,
providing this hack may mask the fact that a given system is indeed
broken. So this patch attempts to apply this unsound hack more narrowly,
providing a strong suggestion to developers and system designers that
this is truly a hack. With luck, system designers can catch their errors
early on in their development cycle, rather than applying this hack long
term. But apparently enough systems are out in the wild that we still
have to provide this hack.

Document a new device tree property to denote systems that do not have a
proper hardware (or software) reset mechanism, and apply the hack (with
a loud warning) only in this case.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

Thanks to the migration of all drivers to use nand_scan() and the
related nand_controller_ops, we can now allocate data during the
detection phase. Let's do it first for the NAND model parameter which
is allocated in nand_detect().
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>

Both nand_scan_ident() and nand_scan_tail() helpers used to be called
directly from controller drivers that needed to tweak some ECC-related
parameters before nand_scan_tail(). This separation prevented dynamic
allocations during the phase of NAND identification, which was
inconvenient.

All controller drivers have been moved to use nand_scan(), in
conjunction with the chip->ecc.[attach|detach]_chip() hooks that
actually do the required tweaking sequence between both ident/tail
calls, allowing programmers to use dynamic allocation as they need all
across the scanning sequence.

Declare nand_scan_[ident|tail]() statically now.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>

In order to remove the limitation that forbids dynamic allocation in
nand_scan_ident(), we must create a path that will be the same for all
controller drivers. The idea is to use nand_scan() instead of the widely
used nand_scan_ident()/nand_scan_tail() couple. In order to achieve
this, controller drivers will need to adjust some parameters between
these two functions depending on the NAND chip wired on them.

This takes the form of two new hooks (->{attach,detach}_chip()) that are
placed in a new nand_controller_ops structure, which is then attached
to the nand_controller object at driver initialization time.
->attach_chip() is called between nand_scan_ident() and
nand_scan_tail(), and ->detach_chip() is called in the error path of
nand_scan() and in nand_cleanup().

Note that some NAND controller drivers don't have a dedicated
nand_controller object and instead rely on the default/dummy one
embedded in nand_chip. If you're in this case and still want to
initialize the controller ops, you'll have to manipulate
chip->dummy_controller directly.

Last but not least, it's worth mentioning that we plan to move some of
the controller related hooks placed in nand_chip into
nand_controller_ops to make the separation between NAND chip and NAND
controller methods clearer.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Acked-by: NBoris Brezillon <boris.brezillon@bootlin.com>

In the raw NAND core, a NAND chip is described by a nand_chip structure,
while a NAND controller is described with a nand_hw_control structure
which is not very meaningful.

Rename this structure nand_controller.

As the structure gets renamed, it is logical to also rename the core
function initializing it from nand_hw_control_init() to
nand_controller_init().

Lastly, the 'hwcontrol' entry of the nand_chip structure is not
meaningful neither while it has the role of fallback when no controller
structure is provided by the driver (the controller driver is dumb and
can only control a single chip). Thus, it is renamed dummy_controller.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Acked-by: NBoris Brezillon <boris.brezillon@bootlin.com>

A report from Colin Ian King pointed a CoverityScan issue where error
values on these helpers where not checked in the drivers. These
helpers can error out only in case of a software bug in driver code,
not because of a runtime/hardware error. Hence, let's WARN_ON() in this
case and return 0 which is harmless anyway.

Fixes: 8878b126 ("mtd: nand: add ->exec_op() implementation")
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Some implementations simply can't disable their ECC engine. Expose
helpers returning -ENOTSUPP so that the caller knows that raw accesses
are not supported instead of silently falling back to non-raw
accessors.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

A comment in the kernel doc of the mtd_oob_ops structure tells that it
is not possible to write more than one page with OOB. This is actually
true for only a few MTD devices like 'onenand' but it is definitely not
a general limitation. While this would benefit to be handled elsewhere
either by the MTD layer or by the limited drivers, let's update this
comment to reflect the reality.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

None of the board files are overloading those hooks, so let's drop them
from struct platform_nand_ctrl.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Acked-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>