Originally, commit d7157ff4 ("mtd: rawnand: Use the ECC framework
user input parsing bits") kind of broke the logic around the
initialization of several ECC engines.

Unfortunately, the fix (which indeed moved the ECC initialization to
the right place) did not take into account the fact that a different
ECC algorithm could have been used thanks to a DT property,
considering the "Hamming" algorithm entry a configuration while it was
only a default.

Add the necessary logic to be sure Hamming keeps being only a default.

Fixes: 59d93473 ("mtd: rawnand: ams-delta: Move the ECC initialization to ->attach_chip()")
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201203190340.15522-2-miquel.raynal@bootlin.com

The probe function is only supposed to initialize the controller
hardware but not the ECC engine. Indeed, we don't know anything about
the NAND chip(s) at this stage. Let's move the logic initializing the
ECC engine, even pretty simple, to the ->attach_chip() hook which gets
called during nand_scan() routine, after the NAND chip discovery. As
the previously mentioned logic is supposed to parse the DT for us, it
is likely that the chip->ecc.* entries be overwritten. So let's avoid
this by moving these lines to ->attach_chip().

Fixes: d7157ff4 ("mtd: rawnand: Use the ECC framework user input parsing bits")
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201113123424.32233-4-miquel.raynal@bootlin.com

Commit 7c2f66a9 ("mtd: rawnand: ams-delta: Add module device
tables") introduced an OF module device table but wrapped a reference
to it with of_match_ptr() which resolves to NULL in non-OF configs.
That resulted in a clang compiler warning on unused variable in non-OF
builds.  Fix it.

drivers/mtd/nand/raw/ams-delta.c:373:34: warning: unused variable 'gpio_nand_of_id_table' [-Wunused-const-variable]
   static const struct of_device_id gpio_nand_of_id_table[] = {
                                    ^
   1 warning generated.

Fixes: 7c2f66a9 ("mtd: rawnand: ams-delta: Add module device tables")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200919080403.17520-1-jmkrzyszt@gmail.com

Mechanical switch from the legacy "mode" enumeration to the new
"engine type" enumeration in drivers and board files.

The device tree parsing is also updated to return the new enumeration
from the old strings.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200827085208.16276-11-miquel.raynal@bootlin.com

NAND_ECC_ is not a meaningful prefix, use NAND_ECC_ALGO_ instead.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200827085208.16276-3-miquel.raynal@bootlin.com

The name/suffix data_interface is a bit misleading in that the field
or functions actually represent a configuration that can be applied by
the controller/chip. Let's rename all fields/functions/hooks that are
worth renaming.
Signed-off-by: NBoris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: NMiquel Raynal <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: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-2-miquel.raynal@bootlin.com

Another step in preparation for merging the driver with "gpio-nand".
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-15-jmkrzyszt@gmail.com

In order to be merged with "gpio-nand", the driver must support custom
(non-GPIO) I/O accessors.

Allow platforms to omit data GPIO port as well as NWE pin info from
device setup.  For the driver to still work on such platform, custom
I/O accessors as well as a custom probe function which initialises the
driver private structure with those accessors must be added to the
driver.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-14-jmkrzyszt@gmail.com

For consistency with adjacent code patterns used in the driver probe
function, store data GPIO array pointer directly in a respective field
of the driver private structure instead of storing it intermediately
in a local variable for error checking.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-13-jmkrzyszt@gmail.com

In preparation for extending the driver with custom I/O support, try to
obtain device specific initialisation routine from a matching device
table entry and run it as an additional step of device probe.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-12-jmkrzyszt@gmail.com

In preparation for merging the driver with "gpio-nand", introduce
module device tables where new device models can be accommodated as
soon as respective support is added.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-11-jmkrzyszt@gmail.com

In order to make the driver more useful on platforms other than Amstrad
Delta, allow GPIO descriptor pointers of possibly non-critical NWP and
NCE pins to be initialised as NULL.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-10-jmkrzyszt@gmail.com

Allow platforms to omit NRE pin from device configuration by requesting
that pin as optional.  In that case, also don't apply read pulse width
from chip SDR timings.  There should be no need for further code
adjustments as gpiolib can handle NULL GPIO descriptor pointers.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-9-jmkrzyszt@gmail.com

Instead of forcing Amstrad Delta specific read/write pulse widths, use
variables initialised from respective fields of chip SDR timings.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-8-jmkrzyszt@gmail.com

Let platforms take care of declaring correct GPIO pin polarity so we
can just ask a GPIO line to be asserted or deasserted and gpiolib deals
with the rest depending on how the platform is configured.

Inspired by similar changes to regulator drivers by Linus Walleij
<linus.walleij@linaro.org>, thanks!
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-7-jmkrzyszt@gmail.com

Provide MTD layer with device OF node info required by OF partition
parser.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-6-jmkrzyszt@gmail.com

Now as we support fetching partition info from device platform data and
the Amstrad Delta board file provides that info, drop it from the
driver code.

v2: rebase on top of gpio_nand_platdata extension
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-5-jmkrzyszt@gmail.com

In order to be able to move the hardcoded Amstrad Delta partition info
from the driver code to the board file, reuse gpio_nand_platdata
structure owned by "gpio-nand" driver and try to obtain information
on device partitions from device platform data.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-3-jmkrzyszt@gmail.com

Initialise NWP GPIO pin as asserted to protect the device from hazard
during setup of other GPIO pins.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200212003929.6682-2-jmkrzyszt@gmail.com

Don't readw()/writew() data directly from/to GPIO port which is under
control of gpio-omap driver, use GPIO consumer API instead.

The driver should now work with any 8-bit bidirectional GPIO port, not
only OMAP.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Data port used by the driver is actually an OMAP MPUIO device, already
under control of gpio-omap driver.  For that reason we used to not
request the memory region of the port as that would fail because the
region is already busy.  Despite that, we are still accessing the port
by just ioremapping it and performing read/write operations.  Moreover,
we are doing that without any proteciton from other users legally
manipulating the port pins over GPIO API.

The plan is to convert the driver to access the port over GPIO consumer
API.  Before that happens, already prevent from other users accessing
the port pins by requesting an array of its GPIO descriptors.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

->exec_op() is a controller method and has nothing to do in the
nand_chip struct. Let's move it to the nand_controller_ops struct and
adjust the core and drivers accordingly.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Now that the CS to be selected is passed in nand_operation->cs, we can
get rid of the ->select_chip() implementation and replace it by an
internal function which is called from the chip->exec_op() hook.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

All NAND objects are supposed to inherit from nand_controller. The
framework is providing a dummy controller object, but we're moving
away from this approach in favor of explicit inheritance.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

mtd_device_register() can fail, and when it does we should propagate
the error and cleanup what has been done before.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Remove unused labels, rename out_mtd into err_unmap to make it clearer
and return 0 instead of using a goto out at the end of the registration
procedure.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Most of them were reported by checkpatch:

* s/u_char/u8/
* remove unneeded blank lines
* don't print warning messages when devm_kzalloc() fails
* Use ! instead of == NULL
* Remove invalid comment
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Add an SPDX GPL-2.0 tag and update MODULE_LICENSE() to match the
license text.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Drop the asm and mach headers inclusion and allow this driver to be
compiled when COMPILE_TEST=y in order to increase compile-test
coverage.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Tested-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Replace legacy callbacks with ->select_chip() and ->exec_op().
Suggested-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Replace use of legacy .IOADDR_R/W with runtime calculations based on
priv->io_base.
Suggested-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

In its current shape, the driver sets data port direction before each
byte read/write operation, even during multi-byte transfers.  Improve
performance of the driver by setting the port direction only when
needed.

This optimisation will become particularly important as soon as
planned conversion of the driver to GPIO API for data I/O will be
implemented.
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Introduce a driver private structure and allocate it on device probe.
Use it for storing nand_chip structure, GPIO descriptors prevoiusly
stored in static variables as well as io_base pointer previously passed
as nand controller data or platform driver data.  Subsequent patches
may populate the structure with more members as needed.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Fix a bug where parent device symlinks aren't shown in sysfs.

While at it, make use of the default owner set by mtdcore.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

Now as Amstrad Delta board - the only user of this driver - provides
GPIO lookup tables, switch from GPIO numbers to GPIO descriptors and
use the table to locate required GPIO pins.

Declare static variables for storing GPIO descriptors and replace
gpio_ function calls with their gpiod_ equivalents.

Pin naming used by the driver should be followed while respective GPIO
lookup table is initialized by a board init code.
Signed-off-by: NJanusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

The wait timeouts and delays are directly extracted from the NAND
timings and ->chip_delay is only used in legacy path, so let's move it
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>