Due to the use of sizeof(), command size set for the spi transfer
was wrong. Driver was sending and receiving always 1 byte less
and especially on write, it was hanging.

echo -n -e "\\x1\\x2\\x3\\x4" > /dev/mtd1

And read part too now works as expected.

hexdump -C -n16 /dev/mtd1
00000000  01 02 03 04 ab f3 ad c2  ab e3 f4 36 dd 38 04 15
00000010

Fixes: 4379075a870b ("mtd: mchp23k256: Add support for mchp23lcv1024")
Signed-off-by: Angelo Dureghello <angelo.dureghello@timesys.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Any write with either dd or flashcp to a device driven by the
spear_smi.c driver will pass through the spear_smi_cpy_toio()
function. This function will get called for chunks of up to 256 bytes.
If the amount of data is smaller, we may have a problem if the data
length is not 4-byte aligned. In this situation, the kernel panics
during the memcpy:

    # dd if=/dev/urandom bs=1001 count=1 of=/dev/mtd6
    spear_smi_cpy_toio [620] dest c9070000, src c7be8800, len 256
    spear_smi_cpy_toio [620] dest c9070100, src c7be8900, len 256
    spear_smi_cpy_toio [620] dest c9070200, src c7be8a00, len 256
    spear_smi_cpy_toio [620] dest c9070300, src c7be8b00, len 233
    Unhandled fault: external abort on non-linefetch (0x808) at 0xc90703e8
    [...]
    PC is at memcpy+0xcc/0x330

The above error occurs because the implementation of memcpy_toio()
tries to optimize the number of I/O by writing 4 bytes at a time as
much as possible, until there are less than 4 bytes left and then
switches to word or byte writes.

Unfortunately, the specification states about the Write Burst mode:

        "the next AHB Write request should point to the next
	incremented address and should have the same size (byte,
	half-word or word)"

This means ARM architecture implementation of memcpy_toio() cannot
reliably be used blindly here. Workaround this situation by update the
write path to stick to byte access when the burst length is not
multiple of 4.

Fixes: f18dbbb1bfe0 ("mtd: ST SPEAr: Add SMI driver for serial NOR flash")
Cc: Russell King <linux@armlinux.org.uk>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: stable@vger.kernel.org
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>

The 'region' field in struct stfsm is unused and can be removed.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/mtd/devices/spear_smi.c: In function spear_smi_probe_config_dt:
drivers/mtd/devices/spear_smi.c:780:32: warning: variable flash_info set but not used [-Wunused-but-set-variable]

It is not used since commit 6551ab5d30d6 ("mtd:
add device-tree support to spear_smi")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: linux-mtd@lists.infradead.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/mtd/devices/pmc551.c: In function pmc551_erase:
drivers/mtd/devices/pmc551.c:142:15: warning: variable soff_lo set but not used [-Wunused-but-set-variable]
drivers/mtd/devices/pmc551.c: In function pmc551_read:
drivers/mtd/devices/pmc551.c:232:15: warning: variable soff_lo set but not used [-Wunused-but-set-variable]
drivers/mtd/devices/pmc551.c: In function pmc551_write:
drivers/mtd/devices/pmc551.c:289:15: warning: variable soff_lo set but not used [-Wunused-but-set-variable]

It is not used since commit cdf0a7d16980 ("[MTD]
pmc551 whitespace cleanup")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

The phram code implements managing multiple devices through a linked
list.
However, due to the module parameter permission of 0, the
/sys/module/phram/parameters/phram interface is missing.
The command line arguments in insmod can only create one device.

Therefore, add writable permissions to the module parameters, create
/sys/module/phram/parameters/phram interface, and create multi-device
support.

Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

The m25p80 driver is actually a generic wrapper around the spi-mem
layer. Not only the driver name is misleading, but we'd expect such a
common logic to be directly available in the core. Another reason for
moving this code is that SPI NOR controller drivers should
progressively be replaced by SPI controller drivers implementing the
spi_mem_ops interface, and when the conversion is done, we should have
a single spi-nor driver directly interfacing with the spi-mem layer.

While moving the code we also fix a longstanding issue when
non-DMA-able buffers are passed by the MTD layer.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

The kbuild documentation clearly shows that the documents
there are written at different times: some use markdown,
some use their own peculiar logic to split sections.

Convert everything to ReST without affecting too much
the author's style and avoiding adding uneeded markups.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Based on 1 normalized pattern(s):

  this code is free software you can redistribute it and or modify it
  under the terms of the gnu general public license version 2 as
  published by the free software foundation

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 6 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190113.627158185@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>