All initialized and registered devices should be listed somewhere so
that we can unregister/free them in the _remove() path.

This patch is not a fix per-se but is needed to apply three other
fixes coming right after, explaining the Fixes/Cc: stable tags.

Fixes: 66859249 ("mtd: nand: Add OX820 NAND Support")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-36-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-35-miquel.raynal@bootlin.com

nand_release() is supposed be called after MTD device registration.
Here, only nand_scan() happened, so use nand_cleanup() instead.

There is no real Fixes tag applying here as the use of nand_release()
in this driver predates by far the introduction of nand_cleanup() in
commit d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
which makes this change possible. However, pointing this commit as the
culprit for backporting purposes makes sense even if this commit is not
introducing any bug.

Fixes: d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-34-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-33-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-32-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-31-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-30-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-29-miquel.raynal@bootlin.com

nand_release() is supposed be called after MTD device registration.
Here, only nand_scan() happened, so use nand_cleanup() instead.

There is no real Fixes tag applying here as the use of nand_release()
in this driver predates the introduction of nand_cleanup() in
commit d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
which makes this change possible. However, pointing this commit as the
culprit for backporting purposes makes sense even if this commit is not
introducing any bug.

Fixes: d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-28-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-27-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-26-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-25-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-24-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Harvey Hunt <harveyhuntnexus@gmail.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-23-miquel.raynal@bootlin.com

nand_release() is supposed be called after MTD device registration.
Here, only nand_scan() happened, so use nand_cleanup() instead.

There is no real Fixes tag applying here as the use of nand_release()
in this driver predates the introduction of nand_cleanup() in
commit d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
which makes this change possible. Hence, pointing it as the commit to
fix for backporting purposes, even if this commit is not introducing
any bug makes sense.

Fixes: d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: stable@vger.kernel.org
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Harvey Hunt <harveyhuntnexus@gmail.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-22-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-21-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-20-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-19-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-18-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-17-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-16-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-15-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-14-miquel.raynal@bootlin.com

Not sure nand_cleanup() is the right function to call here but in any
case it is not nand_release(). Indeed, even a comment says that
calling nand_release() is a bit of a hack as there is no MTD device to
unregister. So switch to nand_cleanup() for now and drop this
comment.

There is no Fixes tag applying here as the use of nand_release()
in this driver predates by far the introduction of nand_cleanup() in
commit d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
which makes this change possible. However, pointing this commit as the
culprit for backporting purposes makes sense even if it did not intruce
any bug.

Fixes: d44154f9 ("mtd: nand: Provide nand_cleanup() function to free NAND related resources")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-13-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-12-miquel.raynal@bootlin.com

Denali driver keeps track of devices with a list. Delete items of this
list as long as they are not in use anymore.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-11-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-10-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-9-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-7-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-6-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Kamal Dasu <kdasu.kdev@gmail.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-5-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-4-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-3-miquel.raynal@bootlin.com

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-2-miquel.raynal@bootlin.com

Add support for the hardware ECC BCH engine.

Please mind that this engine has an important limitation:
BCH implementation does not inform the user when an uncorrectable ECC
error occurs. To workaround this, we avoid using the hardware engine
in the read path and do the computation with the software BCH
implementation, which is faster than mixing hardware (for correction)
and software (for verification).
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200519074549.23673-9-miquel.raynal@bootlin.com

Add the Arasan NAND controller driver. This brings only NAND
controller support. The ECC engine being a bit subtle, hardware ECC
support will be added in a second time.

This work is based on contributions from Naga Sureshkumar Relli.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200519074549.23673-8-miquel.raynal@bootlin.com

Document the Arasan NAND controller bindings.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20200519074549.23673-7-miquel.raynal@bootlin.com

Fill a new entry for the Arasan NAND controller.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519074549.23673-6-miquel.raynal@bootlin.com

There are cases where ECC bytes are not byte-aligned. Indeed, BCH
implies using a number of ECC bits, which are not always a multiple of
8. We then need a helper like nand_extract_bits() to extract these
syndromes from a buffer.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200519074549.23673-5-miquel.raynal@bootlin.com

The main NAND read page function can loop over "page reads" many times
in if the reading reports uncorrectable error(s) and if the chip
supports the read_retry feature.

In this case, the number of bitflips is summarized between
attempts. Fix this by re-initializing the entire mtd_ecc_stats object
each time we retry.
Suggested-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200519074549.23673-4-miquel.raynal@bootlin.com