spi: Unify error codes by replacing -ENOTSUPP with -EOPNOTSUPP

This commit updates the SPI subsystem, particularly affecting "SPI MEM"
drivers and core parts, by replacing the -ENOTSUPP error code with
-EOPNOTSUPP.

The key motivations for this change are as follows:
1. The spi-nor driver currently uses EOPNOTSUPP, whereas calls to spi-mem
might return ENOTSUPP. This update aims to unify the error reporting
within the SPI subsystem for clarity and consistency.

2. The use of ENOTSUPP has been flagged by checkpatch as inappropriate,
mainly being reserved for NFS-related errors. To align with kernel coding
standards and recommendations, this change is being made.

3. By using EOPNOTSUPP, we provide more specific context to the error,
indicating that a particular operation is not supported. This helps
differentiate from the more generic ENOTSUPP error, allowing drivers to
better handle and respond to different error scenarios.

Risks and Considerations:
While this change is primarily intended as a code cleanup and error code
unification, there is a minor risk of breaking user-space applications
that rely on specific return codes for unsupported operations. However,
this risk is considered low, as such use-cases are unlikely to be common
or critical. Nevertheless, developers and users should be aware of this
change, especially if they have scripts or tools that specifically handle
SPI error codes.

This commit does not introduce any functional changes to the SPI subsystem
or the affected drivers.

Signed-off-by: "Chia-Lin Kao (AceLan)" <acelan.kao@canonical.com>
Acked-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20231129064311.272422-1-acelan.kao@canonical.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Use helper function devm_clk_get_enabled()

Since commit 7ef9651e9792 ("clk: Provide new devm_clk helpers for prepared
and enabled clocks"), devm_clk_get() and clk_prepare_enable() can now be
replaced by devm_clk_get_enabled() when driver enables (and possibly
prepares) the clocks for the whole lifetime of the device. Moreover, it is
no longer necessary to unprepare and disable the clocks explicitly.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Link: https://lore.kernel.org/r/20230823133938.1359106-21-lizetao1@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Fix UMA reads when dummy.nbytes == 0

We don't want to use the value of ilog2(0) as dummy.buswidth is 0 when
dummy.nbytes is 0. Since we have no dummy bytes, we don't need to
configure the dummy byte bits per clock register value anyway.

Signed-off-by: "William A. Kennington III" <william@wkennington.com>
Link: https://lore.kernel.org/r/20230922182812.2728066-1-william@wkennington.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: switch to use modern name

Change legacy name master to modern name host or controller.

No functional changed.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20230728093221.3312026-22-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230714174955.4064174-1-robh@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Replace all spi->chip_select and spi->cs_gpiod references with function call

Supporting multi-cs in spi drivers would require the chip_select & cs_gpiod
members of struct spi_device to be an array. But changing the type of these
members to array would break the spi driver functionality. To make the
transition smoother introduced four new APIs to get/set the
spi->chip_select & spi->cs_gpiod and replaced all spi->chip_select and
spi->cs_gpiod references with get or set API calls.
While adding multi-cs support in further patches the chip_select & cs_gpiod
members of the spi_device structure would be converted to arrays & the
"idx" parameter of the APIs would be used as array index i.e.,
spi->chip_select[idx] & spi->cs_gpiod[idx] respectively.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>
Acked-by: Heiko Stuebner <heiko@sntech.de> # Rockchip drivers
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org> # Aspeed driver
Reviewed-by: Dhruva Gole <d-gole@ti.com> # SPI Cadence QSPI
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> # spi-stm32-qspi
Acked-by: William Zhang <william.zhang@broadcom.com> # bcm63xx-hsspi driver
Reviewed-by: Serge Semin <fancer.lancer@gmail.com> # DW SSI part
Link: https://lore.kernel.org/r/167847070432.26.15076794204368669839@mailman-core.alsa-project.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230303172041.2103336-46-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Use devm_platform_ioremap_resource_byname()

Use the devm_platform_ioremap_resource_byname() helper instead of
calling platform_get_resource_byname() and devm_ioremap_resource()
separately.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221029071529.3019626-1-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Add NPCM8XX support

Adding FIU NPCM8XX support to NPCM FIU driver.
NPCM8XX FIU supports four controllers.

As part of adding NPCM8XX support:
- Add NPCM8XX specific compatible string.
- Using an internal burst configuration register instead of a GCR
register.
- Support FIU1 controller.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20220718081146.256070-4-tmaimon77@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Modify direct read dummy configuration

Modify NPCM BMC FIU direct read dummy configuration that according
spi-mem direct read function.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20220718081146.256070-2-tmaimon77@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Fix typo ("npxm")

The platform is called NPCM, not NPXM.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/r/20220306142312.109017-1-j.neuschaefer@gmx.net
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Use of_device_get_match_data()

Use of_device_get_match_data() to simplify the code.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn>
Link: https://lore.kernel.org/r/20220303092131.2060044-1-chi.minghao@zte.com.cn
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Disable clock in probe error path

If the call to devm_spi_register_master() fails on probe of the NPCM FIU
SPI driver, the clock "fiu->clk" is erroneously not unprepared and
disabled. Fix it.

Fixes: ace55c411b11 ("spi: npcm-fiu: add NPCM FIU controller driver")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.4+
Cc: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/9ae62f4e1cfe542bec57ac2743e6fca9f9548f55.1607286887.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Don't leak SPI master in probe error path

If the calls to of_match_device(), of_alias_get_id(),
devm_ioremap_resource(), devm_regmap_init_mmio() or devm_clk_get()
fail on probe of the NPCM FIU SPI driver, the spi_controller struct is
erroneously not freed.

Fix by switching over to the new devm_spi_alloc_master() helper.

Fixes: ace55c411b11 ("spi: npcm-fiu: add NPCM FIU controller driver")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.4+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v5.4+
Cc: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/a420c23a363a3bc9aa684c6e790c32a8af106d17.1605512876.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: simplify the return expression of npcm_fiu_probe()

Simplify the return expression.

Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Link: https://lore.kernel.org/r/20200921131106.93228-1-miaoqinglang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: Reuse BITS_PER_BYTE definition

No need to redefine already existing definition.
So, replace custom by generic one.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200618170144.57433-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

remove ioremap_nocache and devm_ioremap_nocache

ioremap has provided non-cached semantics by default since the Linux 2.6
days, so remove the additional ioremap_nocache interface.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>

spi: npcm-fiu: remove set but not used variable 'retlen'

drivers/spi/spi-npcm-fiu.c: In function npcm_fiu_read:
drivers/spi/spi-npcm-fiu.c:472:9: warning:
variable retlen set but not used [-Wunused-but-set-variable]

It is never used, so remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190905072436.23932-1-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: fix spelling mistake "frequancy" -> "frequency"

There is a spelling mistake in a dev_warning message. Fix it. Also
break line to clear up checkpatch warning.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20190903122812.3986-1-colin.king@canonical.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: npcm-fiu: add NPCM FIU controller driver

Add Nuvoton NPCM BMC Flash Interface Unit(FIU) SPI master
controller driver using SPI-MEM interface.

The FIU supports single, dual or quad communication interface.

the FIU controller can operate in following modes:
- User Mode Access(UMA): provides flash access by using an
indirect address/data mechanism.
- direct rd/wr mode: maps the flash memory into the core
address space.
- SPI-X mode: used for an expansion bus to an ASIC or CPLD.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20190828142513.228556-3-tmaimon77@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>