spi: fsl-spi: 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/20230807124105.3429709-11-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-spi: Do not check 0 for platform_get_irq()

Since platform_get_irq() never returned zero, so it need not to check
whether it returned zero, and we use the return error code of
platform_get_irq() to replace the current return error code, for that
platform_get_irq() may return -EINVAL or -ENXIO.

Signed-off-by: Zhu Wang <wangzhu9@huawei.com>
Link: https://lore.kernel.org/r/20230803083944.21501-1-wangzhu9@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-spi: No need to check transfer length versus word size

The verification is already do in the SPI core by function
__spi_validate(), not it to check it again in fsl_spi_bufs().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/9ace69a8085e22fafd9159e99edd7bbfae2f9940.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-spi: Change mspi_apply_cpu_mode_quirks() to void

mspi_apply_cpu_mode_quirks() always returns the passed bits_per_word
unmodified.

Make it return void, then don't check bits_per_word anymore on
return as it doesn't change.

bits_per_word is already checked by __spi_validate() so no risk to
have bits_per_word higher than 32.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/3142a7c40af12a160f4e134764f2c34da3d8e1e2.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-cpm: Use 16 bit mode for large transfers with even size

On CPM, the RISC core is a lot more efficiant when doing transfers
in 16-bits chunks than in 8-bits chunks, but unfortunately the
words need to be byte swapped as seen in a previous commit.

So, for large tranfers with an even size, allocate a temporary tx
buffer and byte-swap data before and after transfer.

This change allows setting higher speed for transfer. For instance
on an MPC 8xx (CPM1 comms RISC processor), the documentation tells
that transfer in byte mode at 1 kbit/s uses 0.200% of CPM load
at 25 MHz while a word transfer at the same speed uses 0.032%
of CPM load. This means the speed can be 6 times higher in
word mode for the same CPM load.

For the time being, only do it on CPM1 as there must be a
trade-off between the CPM load reduction and the CPU load required
to byte swap the data.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/f2e981f20f92dd28983c3949702a09248c23845c.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-spi: Re-organise transfer bits_per_word adaptation

For different reasons, fsl-spi driver performs bits_per_word
modifications for different reasons:
- On CPU mode, to minimise amount of interrupts
- On CPM/QE mode to work around controller byte order

For CPU mode that's done in fsl_spi_prepare_message() while
for CPM mode that's done in fsl_spi_setup_transfer().

Reunify all of it in fsl_spi_prepare_message(), and catch
impossible cases early through master's bits_per_word_mask
instead of returning EINVAL later.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/0ce96fe96e8b07cba0613e4097cfd94d09b8919a.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-spi: Fix CPM/QE mode Litte Endian

CPM has the same problem as QE so for CPM also use the fix added
by commit 0398fb70940e ("spi/spi_mpc8xxx: Fix QE mode Litte Endian"):

CPM mode uses Little Endian so words > 8 bits are byte swapped.
Workaround this by always enforcing wordsize 8 for 16 and 32 bits
words. Unfortunately this will not work for LSB transfers
where wordsize is > 8 bits so disable these for now.

Also limit the workaround to 16 and 32 bits words because it can
only work for multiples of 8-bits.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Joakim Tjernlund <Joakim.Tjernlund@infinera.com>
Fixes: 0398fb70940e ("spi/spi_mpc8xxx: Fix QE mode Litte Endian")
Link: https://lore.kernel.org/r/1b7d3e84b1128f42c1887dd2fb9cdf390f541bc1.1680371809.git.christophe.leroy@csgroup.eu
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: fsl-spi: 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/20230303172041.2103336-29-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl_spi: Don't change speed while chipselect is active

Commit c9bfcb315104 ("spi_mpc83xx: much improved driver") made
modifications to the driver to not perform speed changes while
chipselect is active. But those changes where lost with the
convertion to tranfer_one.

Previous implementation was allowing speed changes during
message transfer when cs_change flag was set.
At the time being, core SPI does not provide any feature to change
speed while chipselect is off, so do not allow any speed change during
message transfer, and perform the transfer setup in prepare_message
in order to set correct speed while chipselect is still off.

Reported-by: Herve Codina <herve.codina@bootlin.com>
Fixes: 64ca1a034f00 ("spi: fsl_spi: Convert to transfer_one")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Herve Codina <herve.codina@bootlin.com>
Link: https://lore.kernel.org/r/8aab84c51aa330cf91f4b43782a1c483e150a4e3.1671025244.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl_spi: Convert to transfer_one

Let the core handle all the chipselect bakery and replace
transfer_one_message() by transfer_one() and prepare_message().

At the time being, there is fsl_spi_cs_control() to handle
chipselects. That function handles both GPIO and non-GPIO
chipselects. The GPIO chipselects will now be handled by
the core directly, so only handle non-GPIO chipselects and
hook it to ->set_cs

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/753266abafe81722d86c3ddb8bac8ef1cb00fe8c.1660829841.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Cleanup on failure of initial setup

Commit c7299fea6769 ("spi: Fix spi device unregister flow") changed the
SPI core's behavior if the ->setup() hook returns an error upon adding
an spi_device: Before, the ->cleanup() hook was invoked to free any
allocations that were made by ->setup(). With the commit, that's no
longer the case, so the ->setup() hook is expected to free the
allocations itself.

I've identified 5 drivers which depend on the old behavior and am fixing
them up hereinafter: spi-bitbang.c spi-fsl-spi.c spi-omap-uwire.c
spi-omap2-mcspi.c spi-pxa2xx.c

Importantly, ->setup() is not only invoked on spi_device *addition*:
It may subsequently be called to *change* SPI parameters. If changing
these SPI parameters fails, freeing memory allocations would be wrong.
That should only be done if the spi_device is finally destroyed.
I am therefore using a bool "initial_setup" in 4 of the affected drivers
to differentiate between the invocation on *adding* the spi_device and
any subsequent invocations: spi-bitbang.c spi-fsl-spi.c spi-omap-uwire.c
spi-omap2-mcspi.c

In spi-pxa2xx.c, it seems the ->setup() hook can only fail on spi_device
addition, not any subsequent calls. It therefore doesn't need the bool.

It's worth noting that 5 other drivers already perform a cleanup if the
->setup() hook fails. Before c7299fea6769, they caused a double-free
if ->setup() failed on spi_device addition. Since the commit, they're
fine. These drivers are: spi-mpc512x-psc.c spi-pl022.c spi-s3c64xx.c
spi-st-ssc4.c spi-tegra114.c

(spi-pxa2xx.c also already performs a cleanup, but only in one of
several error paths.)

Fixes: c7299fea6769 ("spi: Fix spi device unregister flow")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Saravana Kannan <saravanak@google.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> # pxa2xx
Link: https://lore.kernel.org/r/f76a0599469f265b69c371538794101fa37b5536.1622149321.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: add missing iounmap() on error in of_fsl_spi_probe()

Add the missing iounmap() before return from of_fsl_spi_probe()
in the error handling case.

Fixes: 0f0581b24bd0 ("spi: fsl: Convert to use CS GPIO descriptors")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210401140350.1677925-1-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: invert spisel_boot signal on MPC8309

Commit 7a2da5d7960a ("spi: fsl: Fix driver breakage when SPI_CS_HIGH
is not set in spi->mode") broke our MPC8309 board by effectively
inverting the boolean value passed to fsl_spi_cs_control. The
SPISEL_BOOT signal is used as chipselect, but it's not a gpio, so
we cannot rely on gpiolib handling the polarity.

Adapt to the new world order by inverting the logic here. This does
assume that the slave sitting at the SPISEL_BOOT is active low, but
should that ever turn out not to be the case, one can create a stub
gpiochip driver controlling a single gpio (or rather, a single "spo",
special-purpose output).

Fixes: 7a2da5d7960a ("spi: fsl: Fix driver breakage when SPI_CS_HIGH is not set in spi->mode")
Cc: stable@vger.kernel.org
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Link: https://lore.kernel.org/r/20210130143545.505613-1-rasmus.villemoes@prevas.dk
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Fix driver breakage when SPI_CS_HIGH is not set in spi->mode

Commit 766c6b63aa04 ("spi: fix client driver breakages when using GPIO
descriptors") broke fsl spi driver.

As now we fully rely on gpiolib for handling the polarity of
chip selects, the driver shall not alter the GPIO value anymore
when SPI_CS_HIGH is not set in spi->mode.

Fixes: 766c6b63aa04 ("spi: fix client driver breakages when using GPIO descriptors")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/6b51cc2bfbca70d3e9b9da7b7aa4c7a9d793ca0e.1610629002.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: fix use of spisel_boot signal on MPC8309

Commit 0f0581b24bd0 ("spi: fsl: Convert to use CS GPIO descriptors")
broke the use of the SPISEL_BOOT signal as a chip select on the
MPC8309.

pdata->max_chipselect, which becomes master->num_chipselect, must be
initialized to take into account the possibility that there's one more
chip select in use than the number of GPIO chip selects.

Cc: stable@vger.kernel.org # v5.4+
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Linus Walleij <linus.walleij@linaro.org>
Fixes: 0f0581b24bd0 ("spi: fsl: Convert to use CS GPIO descriptors")
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Link: https://lore.kernel.org/r/20201127152947.376-1-rasmus.villemoes@prevas.dk
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: add missing __iomem annotation

The field mspi->reg_base is annotated as an __iomem pointer. Good.

However, this field is often assigned to a temporary variable:
before being used. For example:
struct fsl_spi_reg *reg_base = mspi->reg_base;

But this variable is missing the __iomem annotation.
So, add the missing __iomem and make sparse & the bot happier.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Link: https://lore.kernel.org/r/20200622162611.83694-1-luc.vanoostenryck@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-fsl-spi: Fix checkpatch error "foo * bar" should be "foo *bar"

This patch fixes checkpatch error "foo * bar" should be "foo *bar"

Signed-off-by: Aishwarya R <aishwaryarj100@gmail.com>
Link: https://lore.kernel.org/r/20200407122855.5531-1-aishwaryarj100@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: simplify error path in of_fsl_spi_probe()

No need to 'goto err;' for just doing a return.
return directly from where the error happens.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Link: https://lore.kernel.org/r/2a4a7e11b37cfa0558d68f0d35e90d6da858b059.1579017697.git.christophe.leroy@c-s.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: use platform_get_irq() instead of of_irq_to_resource()

Unlike irq_of_parse_and_map() which has a dummy definition on SPARC,
of_irq_to_resource() hasn't.

But as platform_get_irq() can be used instead and is generic, use it.

Reported-by: kbuild test robot <lkp@intel.com>
Suggested-by: Mark Brown <broonie@kernel.org>
Fixes: 3194d2533eff ("spi: fsl: don't map irq during probe")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Link: https://lore.kernel.org/r/091a277fd0b3356dca1e29858c1c96983fc9cb25.1576172743.git.christophe.leroy@c-s.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: don't map irq during probe

With lastest kernel, the following warning is observed at startup:

[ 1.500609] ------------[ cut here ]------------
[ 1.505225] remove_proc_entry: removing non-empty directory 'irq/22', leaking at least 'fsl_spi'
[ 1.514234] WARNING: CPU: 0 PID: 1 at fs/proc/generic.c:682 remove_proc_entry+0x198/0x1c0
[ 1.522403] CPU: 0 PID: 1 Comm: swapper Not tainted 5.4.0-s3k-dev-02248-g93532430a4ff #2564
[ 1.530724] NIP: c0197694 LR: c0197694 CTR: c0050d80
[ 1.535762] REGS: df4a5af0 TRAP: 0700 Not tainted (5.4.0-02248-g93532430a4ff)
[ 1.543818] MSR: 00029032 <EE,ME,IR,DR,RI> CR: 22028222 XER: 00000000
[ 1.550524]
[ 1.550524] GPR00: c0197694 df4a5ba8 df4a0000 00000054 00000000 00000000 00004a38 00000010
[ 1.550524] GPR08: c07c5a30 00000800 00000000 00001032 22000208 00000000 c0004b14 00000000
[ 1.550524] GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 c0830000 c07fc078
[ 1.550524] GPR24: c08e8ca0 df665d10 df60ea98 c07c9db8 00000001 df5d5ae3 df5d5a80 df43f8e3
[ 1.585327] NIP [c0197694] remove_proc_entry+0x198/0x1c0
[ 1.590628] LR [c0197694] remove_proc_entry+0x198/0x1c0
[ 1.595829] Call Trace:
[ 1.598280] [df4a5ba8] [c0197694] remove_proc_entry+0x198/0x1c0 (unreliable)
[ 1.605321] [df4a5bd8] [c0067acc] unregister_irq_proc+0x5c/0x70
[ 1.611238] [df4a5bf8] [c005fbc4] free_desc+0x3c/0x80
[ 1.616286] [df4a5c18] [c005fe2c] irq_free_descs+0x70/0xa8
[ 1.621778] [df4a5c38] [c033d3fc] of_fsl_spi_probe+0xdc/0x3cc
[ 1.627525] [df4a5c88] [c02f0f64] platform_drv_probe+0x44/0xa4
[ 1.633350] [df4a5c98] [c02eee44] really_probe+0x1ac/0x418
[ 1.638829] [df4a5cc8] [c02ed3e8] bus_for_each_drv+0x64/0xb0
[ 1.644481] [df4a5cf8] [c02ef950] __device_attach+0xd4/0x128
[ 1.650132] [df4a5d28] [c02ed61c] bus_probe_device+0xa0/0xbc
[ 1.655783] [df4a5d48] [c02ebbe8] device_add+0x544/0x74c
[ 1.661096] [df4a5d88] [c0382b78] of_platform_device_create_pdata+0xa4/0x100
[ 1.668131] [df4a5da8] [c0382cf4] of_platform_bus_create+0x120/0x20c
[ 1.674474] [df4a5df8] [c0382d50] of_platform_bus_create+0x17c/0x20c
[ 1.680818] [df4a5e48] [c0382e88] of_platform_bus_probe+0x9c/0xf0
[ 1.686907] [df4a5e68] [c0751404] __machine_initcall_cmpcpro_cmpcpro_declare_of_platform_devices+0x74/0x1a4
[ 1.696629] [df4a5e98] [c072a4cc] do_one_initcall+0x8c/0x1d4
[ 1.702282] [df4a5ef8] [c072a768] kernel_init_freeable+0x154/0x204
[ 1.708455] [df4a5f28] [c0004b2c] kernel_init+0x18/0x110
[ 1.713769] [df4a5f38] [c00122ac] ret_from_kernel_thread+0x14/0x1c
[ 1.719926] Instruction dump:
[ 1.722889] 2c030000 4182004c 3863ffb0 3c80c05f 80e3005c 388436a0 3c60c06d 7fa6eb78
[ 1.730630] 7fe5fb78 38840280 38634178 4be8c611 <0fe00000> 4bffff6c 3c60c071 7fe4fb78
[ 1.738556] ---[ end trace 05d0720bf2e352e2 ]---

The problem comes from the error path which calls
irq_dispose_mapping() while the IRQ has been requested with
devm_request_irq().

IRQ doesn't need to be mapped with irq_of_parse_and_map(). The only
need is to get the IRQ virtual number. For that, use
of_irq_to_resource() instead of the
irq_of_parse_and_map()/irq_dispose_mapping() pair.

Fixes: 500a32abaf81 ("spi: fsl: Call irq_dispose_mapping in err path")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Link: https://lore.kernel.org/r/518cfb83347d5372748e7fe72f94e2e9443d0d4a.1575905123.git.christophe.leroy@c-s.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Handle the single hardwired chipselect case

The Freescale MPC8xxx had a special quirk for handling a
single hardwired chipselect, the case when we're using neither
GPIO nor native chip select: when inspecting the device tree
and finding zero "cs-gpios" on the device node the code would
assume we have a single hardwired chipselect that leaves the
device always selected.

This quirk is not handled by the new core code, so we need
to check the "cs-gpios" explicitly in the driver and set
pdata->max_chipselect = 1 which will later fall through to
the SPI master ->num_chipselect.

Make sure not to assign the chip select handler in this
case: there is no handling needed since the chip is always
selected, and this is what the old code did as well.

Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Reported-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: 0f0581b24bd0 ("spi: fsl: Convert to use CS GPIO descriptors")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> (No tested the
Link: https://lore.kernel.org/r/20191128083718.39177-3-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Fix GPIO descriptor support

This makes the driver actually support looking up GPIO
descriptor. A coding mistake in the initial descriptor
support patch was that it was failing to turn on the very
feature it was implementing. Mea culpa.

Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Reported-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: 0f0581b24bd0 ("spi: fsl: Convert to use CS GPIO descriptors")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Link: https://lore.kernel.org/r/20191128083718.39177-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: use new `spi_transfer_delay_exec` helper where straightforward

For many places in the spi drivers, using the new `spi_transfer_delay`
helper is straightforward.
It's just replacing:
```
if (t->delay_usecs)
udelay(t->delay_usecs);
```
with `spi_transfer_delay(t)` which handles both `delay_usecs` and the new
`delay` field.

This change replaces in all places (in the spi drivers) where this change
is simple.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-10-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Convert to use CS GPIO descriptors

This converts the Freescale SPI master driver to use GPIO
descriptors for chip select handling.

The Freescale (fsl) driver has a lot of quirks to look up
"gpios" rather than "cs-gpios" from the device tree.
After the prior patch that will make gpiolib return the
GPIO descriptor for "gpios" in response to a request for
"cs-gpios", this code can be cut down quite a bit.

The driver has custom handling of chip select rather
than using the core (which may be possible but not
done in this patch) so it still needs to refer directly
to spi->cs_gpiod to set the chip select.

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190804003539.985-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spi: spi-fsl-spi: call spi_finalize_current_message() at the end

spi_finalize_current_message() shall be called once all
actions are finished, otherwise the last actions might
step over a newly started transfer.

Fixes: c592becbe704 ("spi: fsl-(e)spi: migrate to generic master queueing")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-fsl-spi: automatically adapt bits-per-word in cpu mode

Taking one interrupt for every byte is rather slow. Since the
controller is perfectly capable of transmitting 32 bits at a time,
change t->bits_per-word to 32 when the length is divisible by 4 and
large enough that the reduced number of interrupts easily compensates
for the one or two extra fsl_spi_setup_transfer() calls this causes.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-fsl-spi: allow changing bits_per_word while CS is still active

Commit c9bfcb315104 (spi_mpc83xx: much improved driver) introduced
logic to ensure bits_per_word and speed_hz stay the same for a series
of spi_transfers with CS active, arguing that

The current driver may cause glitches on SPI CLK line since one
must disable the SPI controller before changing any HW settings.

This sounds quite reasonable. So this is a quite naive attempt at
relaxing this sanity checking to only ensure that speed_hz is
constant - in the faint hope that if we do not causes changes to the
clock-related fields of the SPMODE register (DIV16 and PM), those
glitches won't appear.

The purpose of this change is to allow automatically optimizing large
transfers to use 32 bits-per-word; taking one interrupt for every byte
is extremely slow.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-fsl-spi: relax message sanity checking a little

The comment says that we should not allow changes (to
bits_per_word/speed_hz) while CS is active, and indeed the code below
does fsl_spi_setup_transfer() when the ->cs_change of the previous
spi_transfer was set (and for the very first transfer).

So the sanity checking is a bit too strict - we can change it to
follow the same logic as is used by the actual transfer loop.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-fsl-spi: remove always-true conditional in fsl_spi_do_one_msg

__spi_validate() in the generic SPI code sets ->speed_hz and
->bits_per_word to non-zero values, so this condition is always true.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-fsl-spi: support use of the SPISEL_BOOT signal on MPC8309

The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip
select for the flash device from which the bootloader is loaded. It is
not an ordinary gpio, but is simply controlled via the SPI_CS register
in the system configuration.

To allow accessing such a spi slave, we need to teach
fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To
distinguish the gpio-controlled slaves, continue to have those use
chip_select values of 0..ngpios-1, and use chip_select == ngpios for
the boot flash.

I'm not too happy with all the ifdeffery, but it seems to be necessary
for guarding the sysdev/fsl_soc.h and use of
get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery).

Googling suggests that the MPC8306 is similar, with the SPI_CS
register at the same offset.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Call irq_dispose_mapping in err path

Irq_dispose_mapping should be called in err path to release
the resources that irq_of_parse_and_map requested.

Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Combine substrings for two messages

The script "checkpatch.pl" pointed information out like the following.

WARNING: quoted string split across lines

Thus fix the affected source code places.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Use kcalloc() in of_fsl_spi_get_chipselects()

A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus reuse the corresponding function "kcalloc".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Use kmalloc_array() in of_fsl_spi_get_chipselects()

A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-(e)spi: Fix checking return value of devm_ioremap_resource

devm_ioremap_resource() returns ERR_PTR on error.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-(e)spi: simplify cleanup code

Now that most cleanup is done automatically the remove functions
can be significantly simplified.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-(e)spi: migrate to using devm_ functions to simplify cleanup

Migrate fsl-espi and fsl-spi to using the managed devm_ functions
for resource handling. This simplifies the cleanup.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-spi: remove unused variable assignment

Remove an unused variable assignment.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-fsl-spi: Return an error code in fsl_spi_do_one_msg()

Since commit c592becbe704127 ("spi: fsl-(e)spi: migrate to generic master
queueing") the function fsl_spi_do_one_msg() is not void anymore, so return
an error code to avoid the following buid warning:

drivers/spi/spi-fsl-spi.c: In function 'fsl_spi_do_one_msg':
>> drivers/spi/spi-fsl-spi.c:374:4: warning: 'return' with no value, in function returning non-void [-Wreturn-type]
return;
^

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl-(e)spi: migrate to generic master queueing

Migrates the fsl-(e)spi driver to use the generic master queuing.
Avoids the "master is unqueued, this is deprecated" warning.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: drop owner assignment from platform_drivers

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

spi: fsl: Sort include headers alphabetically

Sort all the include headers alphabetically for the freescale
spi drivers. If the inlcude headers sorted out of order, maybe
the best logical choice is to append new ones after the exist
ones, while this may create a lot of potential for duplicates
and conflicts for each diffenent changes will add new headers
in the same location.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fsl: Don't use devm_kzalloc in master->setup callback

device_add() expects that any memory allocated via devm_* API is only
done in the device's probe function.

Fix below boot warning:
[ 3.092348] WARNING: at drivers/base/dd.c:286
[ 3.096637] Modules linked in:
[ 3.099697] CPU: 0 PID: 25 Comm: kworker/u2:1 Tainted: G W 3.16.1-s3k-drv-999-svn5771_knld-999 #158
[ 3.109610] Workqueue: deferwq deferred_probe_work_func
[ 3.114736] task: c787f020 ti: c790c000 task.ti: c790c000
[ 3.120062] NIP: c01df158 LR: c01df144 CTR: 00000000
[ 3.124983] REGS: c790db30 TRAP: 0700 Tainted: G W (3.16.1-s3k-drv-999-svn5771_knld-999)
[ 3.134162] MSR: 00029032 <EE,ME,IR,DR,RI> CR: 22002082 XER: 20000000
[ 3.140703]
[ 3.140703] GPR00: 00000001 c790dbe0 c787f020 00000044 00000054 00000308 c056da0e 20737069
[ 3.140703] GPR08: 33323736 000ebfe0 00000308 000ebfdf 22002082 00000000 c046c5a0 c046c608
[ 3.140703] GPR16: c046c614 c046c620 c046c62c c046c638 c046c648 c046c654 c046c68c c046c6c4
[ 3.140703] GPR24: 00000000 00000000 00000003 c0401aa0 c0596638 c059662c c054e7a8 c7996800
[ 3.170102] NIP [c01df158] driver_probe_device+0xf8/0x334
[ 3.175431] LR [c01df144] driver_probe_device+0xe4/0x334
[ 3.180633] Call Trace:
[ 3.183093] [c790dbe0] [c01df144] driver_probe_device+0xe4/0x334 (unreliable)
[ 3.190147] [c790dc10] [c01dd15c] bus_for_each_drv+0x7c/0xc0
[ 3.195741] [c790dc40] [c01df5fc] device_attach+0xcc/0xf8
[ 3.201076] [c790dc60] [c01dd6d4] bus_probe_device+0xb4/0xc4
[ 3.206666] [c790dc80] [c01db9f8] device_add+0x270/0x564
[ 3.211923] [c790dcc0] [c0219e84] spi_add_device+0xc0/0x190
[ 3.217427] [c790dce0] [c021a79c] spi_register_master+0x720/0x834
[ 3.223455] [c790dd40] [c021cb48] of_fsl_spi_probe+0x55c/0x614
[ 3.229234] [c790dda0] [c01e0d2c] platform_drv_probe+0x30/0x74
[ 3.234987] [c790ddb0] [c01df18c] driver_probe_device+0x12c/0x334
[ 3.241008] [c790dde0] [c01dd15c] bus_for_each_drv+0x7c/0xc0
[ 3.246602] [c790de10] [c01df5fc] device_attach+0xcc/0xf8
[ 3.251937] [c790de30] [c01dd6d4] bus_probe_device+0xb4/0xc4
[ 3.257536] [c790de50] [c01de9d8] deferred_probe_work_func+0x98/0xe0
[ 3.263816] [c790de70] [c00305b8] process_one_work+0x18c/0x440
[ 3.269577] [c790dea0] [c0030a00] worker_thread+0x194/0x67c
[ 3.275105] [c790def0] [c0039198] kthread+0xd0/0xe4
[ 3.279911] [c790df40] [c000c6d0] ret_from_kernel_thread+0x5c/0x64
[ 3.285970] Instruction dump:
[ 3.288900] 80de0000 419e01d0 3b7b0038 3c60c046 7f65db78 38635264 48211b99 813f00a0
[ 3.296559] 381f00a0 7d290278 3169ffff 7c0b4910 <0f000000> 93df0044 7fe3fb78 4bfffd4d

Reported-by: leroy christophe <christophe.leroy@c-s.fr>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: fsl-spi: Make of_device_id array const

Make of_device_id array const, because all OF functions handle
it as const.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: fsl-spi: Fix memory leak

mpc8xxx_spi_probe() has set master->cleanup = mpc8xxx_spi_cleanup,
however current code overrides the setting in fsl_spi_probe() and set
master->cleanup = fsl_spi_cleanup.
Thus the memory allocated for cs is not freed anywhere.
Convert to use devm_kzalloc to fix the memory leak.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: Always check complete callback before calling it

Since commit 1e25cd4729bd "spi: Do not require a completion", this checking is
required to prevent NULL pointer dereference.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: fsl-spi: Convert to let spi core validate xfer->bits_per_word

Set bits_per_word_mask so spi core will reject transfers that attempt to use
an unsupported bits_per_word value.

fsl_spi_grlib_probe() may update mpc8xxx_spi->max_bits_per_word setting.
So set master->bits_per_word_mask after fsl_spi_grlib_probe().

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: fsl: Fix problem with multi message transfers

When used via spidev with more than one messages to tranfer via
SPI_IOC_MESSAGE the current implementation would return with
-EINVAL, since bits_per_word and speed_hz are set in all
transfer structs. And in the 2nd loop status will stay at
-EINVAL as its not overwritten again via fsl_spi_setup_transfer().

This patch changes this behavious by first checking if one of
the messages uses different settings. If this is the case
the function will return with -EINVAL. If not, the messages
are transferred correctly.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

tree-wide: use reinit_completion instead of INIT_COMPLETION

Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: use dev_get_platdata()

Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

PTR_RET is now PTR_ERR_OR_ZERO(): Replace most.

Sweep of the simple cases.

Cc: netdev@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

spi: use platform_{get,set}_drvdata()

Use the wrapper functions for getting and setting the driver data using
platform_device instead of using dev_{get,set}_drvdata() with &pdev->dev,
so we can directly pass a struct platform_device.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/spi-fsl-spi: Add support for gpio chipselects for GRLIB type cores

This relies upon of_spi_register_master to find out which gpios to use.

Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/spi-fsl-spi: Add support for Aeroflex Gaisler GRLIB cores normally running on SPARC

This adds support for the mostly register-compatible SPICTRL cores from the
GRLIB VHDL IP core library from Aeroflex Gaisler. They are normally running on
SPARC. A different entry in of_fsl_spi_match matches this core and indicates a
different hardware type that is used to set up different function pointers and
special cases.

The GRLIB core operates in cpu mode. The number of bits per word might be
limited. There might be native chipselects selected via a slave select
register. These differences to the FSL type cores, if present, are indicated by
a capabilities register. Other register and function differences exists but are
not relevant to the driver.

Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/spi-fsl-spi: Add support for setting a maximum number of bits per word

Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/spi-fsl-spi: Introduce a type for the driver

For being able to distinguishing between the regular type of cores and others
with different entries in of_fsl_spi_match.

Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/spi-fsl-spi: Move setting non-zero tx and rx shifts to a function accessed by a function pointer

Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/spi-fsl-spi: Make sure in spi_fsl_setup that chipselect becomes inactive

This is needed for a device in SPI_CS_HIGH mode that otherwise could start out
active for the first transaction.

Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/spi-fsl-spi: Make driver usable in CPU mode outside of an FSL_SOC environment

This makes the spi-fsl-spi driver usable in CPU mode outside of an FSL_SOC and
even an powerpc environment by moving CPM mode functionality to a separate file
that is only compiled and linked in an FSL_SOC environment and adding some
ifdefs to hide types and functions or provide alternatives.

For devicetree probing a "clock-frequency" property is used for clock frequency
instead of calls to FSL_SOC-specific functions.

Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/fsl: Use PTR_RET function

Replaced calls to IS_ERR and PTR_ERR with PTR_RET function.
Patch found using coccinelle.

Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

gpio: Make of_count_named_gpios() use new of_count_phandle_with_args()

This patch replaces the horribly coded of_count_named_gpios() with a
call to of_count_phandle_with_args() which is far more efficient. This
also changes the return value of of_gpio_count() & of_gpio_named_count()
from 'unsigned int' to 'int' so that it can return an error code. All
the users of that function are fixed up to correctly handle a negative
return value.

v2: Split GPIO portion into a separate patch

Tested-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>

spi: Remove HOTPLUG section attributes

CONFIG_HOTPLUG is going away as an option. As result the __dev*
markings will be going away.

Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.

Bill Pemberton has done most of the legwork on this series. I've used
his script to purge the attributes from the drivers/gpio tree.

Reported-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/spi-fsl-spi: reference correct pdata in fsl_spi_cs_control

Commit 178db7d3, "spi: Fix device unregistration when unregistering
the bus master", changed spi device initialization of dev.parent pointer
to be the master's device pointer instead of his parent.

This introduced a bug in spi-fsl-spi, since its usage of spi device
pointer was not updated accordingly. This was later fixed by commit
5039a86, "spi/mpc83xx: fix NULL pdata dereference bug", but it missed
another spot on fsl_spi_cs_control function where we also need to update
usage of spi device pointer. This change address that.

Cc: stable@vger.kernel.org
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Acked-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/mpc83xx: fix NULL pdata dereference bug

Commit 178db7d3, "spi: Fix device unregistration when unregistering
the bus master", changed device initialization to be children of the
bus master, not children of the bus masters parent device. The pdata
pointer used in fsl_spi_chipselect must updated to reflect the changed
initialization.

Signed-off-by: Kenth Eriksson <kenth.eriksson@transmode.com>
Acked-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: Fix WARN when removing spi-fsl-spi module

If CPM mode is not used, the fsl_dummy_rx variable is never allocated. When
the cleanup attempts to free it, the reference count is zero and a WARN is
generated. The same CPM mode check used in the initialize is applied to the
free as well.

Tested on 2.6.33 with the previous spi_mpc8xxx driver. The renamed
spi-fsl-spi driver looks to have the same problem.

Signed-off-by: Jeff Harris <jeff_harris@kentrox.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/fsl_spi: fix CPM spi driver

This patch fixes the freescale spi driver for CPM. Without this
patch SPI on CPM failed because cpm_muram_alloc_fixed tries to
allocate muram in an preserved area. The error reported was:

mpc8xxx_spi f0011a80.spi: can't allocate spi parameter ram
mpc8xxx_spi: probe of f0011a80.spi failed with error -12

Now the driver uses of_iomap to get access to this area
similar to i2c driver driver in the i2c-cpm.c which has a
similar device tree node. This is tested on a MPC8247 with CPM2.

Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: reorganize drivers

Sort the SPI makefile and enforce the naming convention spi_*.c for
spi drivers.

This change also rolls the contents of atmel_spi.h into the .c file
since there is only one user of that particular include file.

v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be
be the predominant pattern for subsystem prefixes.
- Clean up filenames in Kconfig and header comment blocks

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>