Use the new of_get_compatible_child() helper to lookup the nfc child
node instead of using of_find_compatible_node(), which searches the
entire tree from a given start node and thus can return an unrelated
(i.e. non-child) node.

This also addresses a potential use-after-free (e.g. after probe
deferral) as the tree-wide helper drops a reference to its first
argument (i.e. the node of the device being probed).

While at it, also fix a related nfc-node reference leak.

Fixes: f88fc122 ("mtd: nand: Cleanup/rework the atmel_nand driver")
Cc: stable <stable@vger.kernel.org>     # 4.11
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Josh Wu <rainyfeeling@outlook.com>
Cc: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

There is a potential execution path in which function
of_find_compatible_node() returns NULL. In such a case,
we end up having a NULL pointer dereference when accessing
pointer *nfc_np* in function of_clk_get().

So, we better don't take any chances and fix this by null
checking pointer *nfc_np* before calling of_clk_get().

Addresses-Coverity-ID: 1473052 ("Dereference null return value")
Fixes: f88fc122 ("mtd: nand: Cleanup/rework the atmel_nand driver")
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Acked-by: NTudor Ambarus <tudor.ambarus@microchip.com>
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Those hooks have been replaced by -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Those hooks have been replaced by -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All those hooks have been replaced by -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>

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->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->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 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 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>

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
	int stuff;
        void *entry[];
};

instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL);

This issue was detected with the help of Coccinelle.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
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>

Two helpers have been added to the core to do all kind of controller
side configuration/initialization between the detection phase and the
final NAND scan. Implement these hooks so that we can convert the driver
to just use nand_scan() instead of the nand_scan_ident() +
nand_scan_tail() pair.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>

No need for an atmel_nand_register() function, let's move the code in
it directly where the function was called: in
atmel_nand_controller_add_nand(). To make things consistent, also
rename atmel_nand_unregister() into
atmel_nand_controller_remove_nand().
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>

gpio/consumer.h defines everything we need, and it's clearly stated in
gpio.h that GPIO consumers should directly stop including gpio.h if they
can.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@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>

gen_pool_dma_alloc() return type is void *, while internally, the
memory region exposed by the sram driver has been mapped with
ioremap().

Add a void * to void __iomem * cast to make sparse happy.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

When casting a pointer to an unsigned int, uintptr_t should be used to
cope with the pointer size differences between 32-bit and 64-bit
architectures.

This is needed if we want to allow compilation of this driver when
COMPILE_TEST=y.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

On a sama5d31 with a Full-HD dual LVDS panel (132MHz pixel clock) NAND
flash accesses have a tendency to cause display disturbances. Add a
module param to disable DMA from the NAND controller, since that fixes
the display problem for me.
Signed-off-by: NPeter Rosin <peda@axentia.se>
Reviewed-by: NBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>

As part of the process of sharing more code between different NAND
based devices, we need to move all raw NAND related code to the raw/
subdirectory.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

A lot of NAND drivers have been derived from other old NAND drivers
which have since then been removed from the Linux tree. When this is
the case, specify when the file the header is referring to has been
removed so that people can find the original implementation more
easily.
Signed-off-by: NBoris Brezillon <boris.brezillon@bootlin.com>

The core currently send the READ0 and SEQIN+PAGEPROG commands in
nand_do_read/write_ops(). This is inconsistent with
->read/write_oob[_raw]() hooks behavior which are expected to send
these commands.

There's already a flag (NAND_ECC_CUSTOM_PAGE_ACCESS) to inform the core
that a specific controller wants to send the READ/SEQIN+PAGEPROG
commands on its own, but it's an opt-in flag, and existing drivers are
unlikely to be updated to pass it.

Moreover, some controllers cannot dissociate the READ/PAGEPROG commands
from the associated data transfer and ECC engine activation, and
developers have to hack things in their ->cmdfunc() implementation to
handle such complex cases, or have to accept the perf penalty of sending
twice the same command.
To address this problem we are planning on adding a new interface which
is passed all information about a NAND operation (including the amount
of data to transfer) and replacing all calls to ->cmdfunc() to calls to
this new ->exec_op() hook. But, in order to do that, we need to have all
->cmdfunc() calls placed near their associated ->read/write_buf/byte()
calls.

Modify the core and relevant drivers to make NAND_ECC_CUSTOM_PAGE_ACCESS
the default case, and remove this flag.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
[miquel.raynal@free-electrons.com: tested, fixed and rebased on nand/next]
Signed-off-by: NMiquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

This is part of the process of removing direct calls to ->cmdfunc()
outside of the core in order to introduce a better interface to execute
NAND operations.

Here we provide several helpers and make use of them to remove all
direct calls to ->cmdfunc(). This way, we can easily modify those
helpers to make use of the new ->exec_op() interface when available.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
[miquel.raynal@free-electrons.com: rebased and fixed some conflicts]
Signed-off-by: NMiquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

commit 6e532afa ("mtd: nand: atmel: Add PM ops") was defining PM
ops but nothing was using/referencing those PM ops.

Fixes: 6e532afa ("mtd: nand: atmel: Add PM ops")
Cc: <stable@vger.kernel.org>
Cc: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NWenyou Yang <wenyou.yang@microchip.com>
Tested-by: NRomain Izard <romain.izard.pro@gmail.com>

During backup mode, the contents of all registers will be cleared as the
SoC will be completely powered down. For a product that boots on NAND
Flash memory, the bootloader will obviously use the related controller
to read the Flash and correct any detected error in the memory, before
handling back control to the kernel's resuming entry point.

But it does not clean the NAND controller registers after use and on its
side the kernel driver expects the error locator to be powered down and
in a clean state. Add a resume hook for the PMECC error locator, and
reset its registers.
Signed-off-by: NRomain Izard <romain.izard.pro@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Several drivers check ->chipsize to see if the third row address cycle
is needed.  Instead of embedding magic sizes such as 32MB, 128MB in
drivers, introduce a new flag NAND_ROW_ADDR_3 for clean-up.  Since
nand_scan_ident() knows well about the device, it can handle this
properly.  The flag is set if the row address bit width is greater
than 16.

Delete comments such as "One more address cycle for ..." because
intention is now clear enough from the code.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NWenyou Yang <wenyou.yang@microchip.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

For HSMC controller, the register layout depends on the device i.e. the
offset of setup, pulse, cycle, mode and timings registers is not the
same. An helper is added to provide the correct register layout.

Fixes: fe9d7cb2 ("mfd: syscon: atmel-smc: Add new helpers to ease
SMC regs manipulation")
Suggested-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NLudovic Desroches <ludovic.desroches@microchip.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

Version 4 of the ONFI spec mandates that tADL be at least 400 nanoseconds,
but, depending on the master clock rate, 400 ns may not fit in the tADL
field of the SMC reg. We need to relax the check and accept the -ERANGE
return code.

Note that previous versions of the ONFI spec had a lower tADL_min (100 or
200 ns). It's not clear why this timing constraint got increased but it
seems most NANDs are fine with values lower than 400ns, so we should be
safe.

Fixes: f9ce2edd ("mtd: nand: atmel: Add ->setup_data_interface() hooks")
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: NQuentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

of_irq_get() may return 0 as well as negative error number on failure,
while the driver only checks for the negative values. The driver would
then call devm_request_irq() for IRQ0  in its probe method and never get
a valid interrupt.

Check for 'nc->irq <= 0' instead and return -ENXIO from the driver's probe
if of_irq_get() returned 0.

Fixes: f88fc122 ("mtd: nand: Cleanup/rework the atmel_nand driver")
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: NWenyou Yang <Wenyou.yang@microchip.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

We are planning to share more code between different NAND based
devices (SPI NAND, OneNAND and raw NANDs), but before doing that
we need to move the existing include/linux/mtd/nand.h file into
include/linux/mtd/rawnand.h so we can later create a nand.h header
containing all common structure and function prototypes.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NPeter Pan <peterpandong@micron.com>
Acked-by: NVladimir Zapolskiy <vz@mleia.com>
Acked-by: NAlexander Sverdlin <alexander.sverdlin@gmail.com>
Acked-by: NWenyou Yang <wenyou.yang@microchip.com>
Acked-by: NKrzysztof Kozlowski <krzk@kernel.org>
Acked-by: NHan Xu <han.xu@nxp.com>
Acked-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: NShawn Guo <shawnguo@kernel.org>
Acked-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: NNeil Armstrong <narmstrong@baylibre.com>
Acked-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-By: NHarvey Hunt <harveyhuntnexus@gmail.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Acked-by: NKrzysztof Halasa <khalasa@piap.pl>

EDO mode should be used when tRC is less than 30ns, but timings are
expressed in picoseconds in the nand_sdr_timings struct.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Fixes: f9ce2edd ("mtd: nand: atmel: Add ->setup_data_interface() hooks")
Reported-by: NAlexander Dahl <ada@thorsis.com>
Tested-by: NAlexander Dahl <ada@thorsis.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The Atmel NAND driver doesn't used anything from
linux/platform_data/atmel.h, stop including it.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The newly added suspend/resume support causes a harmless warning:

drivers/mtd/nand/atmel/nand-controller.c:2513:12: error: 'atmel_nand_controller_resume' defined but not used [-Werror=unused-function]

This shuts up the warning with a __maybe_unused annotation.

Fixes: b107007a7114 ("mtd: nand: atmel: Add PM ops")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Drivers setting NAND_ECC_CUSTOM_PAGE_ACCESS are supposed to handle the
full read/write page sequence, and waiting for a page to actually be
programmed is part of this write-page sequence.
This is also what is done in ->write_oob_xxx() hooks, so let's do that in
->write_page_xxx() as well to make it consistent.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>