spi: s3c64xx: change polling mode to optional

Previously, Polling mode was supported as quirk for SOC without DMA.
To provide more flexible support for polling mode, it changed to polling
mode when the 'dmas' property is not present in the devicetree, rather than
using a quirk.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org
Link: https://lore.kernel.org/r/20230502062813.112434-2-jaewon02.kim@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org

spi: s3c64xx: add no_cs description

This patch adds missing variable no_cs descriptions.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Link: https://lore.kernel.org/r/20230306014239.80570-1-jaewon02.kim@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Convert to use GPIO descriptors

Convert the S3C64xx SPI host to use GPIO descriptors.

Provide GPIO descriptor tables for the one user with CS
0 and 1.

Cc: linux-samsung-soc@vger.kernel.org
Cc: Sylwester Nawrocki <snawrocki@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220118230915.157797-3-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Drop custom gpio setup argument

The SPI0 platform population function was taking a custom
gpio setup callback but the only user pass NULL as
argument so drop this argument.

Cc: linux-samsung-soc@vger.kernel.org
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc: Sylwester Nawrocki <snawrocki@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20220118230915.157797-2-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Delete unused boardfile helpers

The helpers to use SPI host 1 and 2 are unused in the kernel
and taking up space and maintenance hours. New systems should
use device tree and not this, so delete the code.

Cc: linux-samsung-soc@vger.kernel.org
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc: Sylwester Nawrocki <snawrocki@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220118230915.157797-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: add SPDX identifier

Replace the original license statement with the SPDX identifier.

Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

ARM: s3c64xx: Drop unused DMA fields from struct s3c64xx_spi_csinfo

There is no drivers using those fields so remove them and
the remaining initializations.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

spi: s3c64xx: consider the case when the CS line is not connected

When the CS line is not connected, it is not needed to enable or
disable the chip selection functionality from the s3c64xx
devices in order to perform a transfer.
Set the CS controller logically always enabled already during
initialization (by writing '0' in the S3C64XX_SPI_SLAVE_SEL
register) and never disable it.

Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: pass DMA arguments in platform data

The s3c64xx platform data already contains a pointer to the
DMA filter function, but not to the associated data.

This simplifies the code and makes it more generic by
passing the data along with the filter function like
we do for other drivers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi/s3c64xx: Trivial cleanup in header file

Commit 436d42c61c3e ("ARM: samsung: move platform_data definitions")
moved the files to the current location but forgot to remove the pointer
to its previous location. Clean it up. While at it also change the header
file protection macros appropriately.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: move to generic dmaengine API

The spi-s3c64xx uses a Samsung proprietary interface for
talking to the DMA engine, which does not work with
multiplatform kernels.

This version of the patch leaves the old code in place,
behind an #ifdef. This can be removed in the future,
after the s3c64xx platform start supporting the regular
dmaengine interface. An earlier version of this patch was
tested successfully on exynos5250 by Padma Venkat.

The conversion was rather mechanical, since the samsung
interface is just a shallow wrapper around the dmaengine
interface.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: samsung: move platform_data definitions

Platform data for device drivers should be defined in
include/linux/platform_data/*.h, not in the architecture
and platform specific directories.

This moves such data out of the samsung include directories

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: "Wolfram Sang (embedded platforms)" <w.sang@pengutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Bryan Wu <bryan.wu@canonical.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Chris Ball <cjb@laptop.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sangbeom Kim <sbkim73@samsung.com>
Cc: Liam Girdwood <lrg@ti.com>
Cc: linux-samsung-soc@vger.kernel.org