spi: s3c64xx: Use DMA mode from fifo size

If the SPI data size is smaller than FIFO, it operates in PIO mode,
and if it is larger than FIFO size, it oerates in DMA mode.

If the SPI data size is equal to fifo, it operates in PIO mode and it is
separated to 2 transfers. To prevent it, it must operate in DMA mode
from the case where the data size and the fifo size are the same.

Fixes: 1ee806718d5e ("spi: s3c64xx: support interrupt based pio mode")
Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20240329085840.65856-1-jaewon02.kim@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: switch exynos850 to new port config data

Exynos850 has the same version of USI SPI (v2.1) as GS101.
Drop the fifo_lvl_mask and rx_lvl_offset and switch to the new port
config data.

Backward compatibility with DT is not broken because when alises are
set:
- the SPI core will set the bus number according to the alias ID
- the FIFO depth is always the same size for exynos850 (64 bytes) no
matter the alias ID number.

Advantages of the change:
- drop dependency on the OF alias ID.
- FIFO depth is inferred from the compatible. Exynos850 integrates 3 SPI
IPs, all with 64 bytes FIFO depths.
- use full mask for SPI_STATUS.{RX, TX}_FIFO_LVL fields. Using partial
masks is misleading and can hide problems of the driver logic.

Just compiled tested.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-13-tudor.ambarus@linaro.org
Tested-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: switch gs101 to new port config data

Drop the fifo_lvl_mask and rx_lvl_offset and switch to the new port
config data.

Advantages of the change:
- drop dependency on the OF alias ID.
- FIFO depth is inferred from the compatible. GS101 integrates 16 SPI
IPs, all with 64 bytes FIFO depths.
- use full mask for SPI_STATUS.{RX, TX}_FIFO_LVL fields. Using partial
masks is misleading and can hide problems of the driver logic.

S3C64XX_SPI_ST_TX_FIFO_RDY_V2 was defined based on the USI's
SPI_VERSION.USI_IP_VERSION register field, which has value 2 at reset.

MAX_SPI_PORTS is updated to reflect the maximum number of ports for the
rest of the compatibles.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-12-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: deprecate fifo_lvl_mask, rx_lvl_offset and port_id

Deprecate fifo_lvl_mask, rx_lvl_offset and port_id. One shall use
{rx, tx}_fifomask instead. Add messages to each port configuration.

Suggested-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-11-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: get rid of the OF alias ID dependency

Compatibles that set ``port_conf->{rx, tx}_fifomask`` are now safe to
get rid of the OF alias ID dependency. Let the driver probe even without
the alias for these.

With this we also protect the FIFO_LVL_MASK calls from
s3c64xx_spi_set_fifomask().

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-10-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: introduce s3c64xx_spi_set_port_id()

Prepare driver to get rid of the of alias ID dependency. Split the
port_id logic into a dedicated method.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-9-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: let the SPI core determine the bus number

Let the core determine the bus number, either by getting the alias ID
(as the driver forces now), or by allocating a dynamic bus number when
the alias is absent. Prepare the driver to allow dt aliases to be
absent.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-8-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: allow FIFO depth to be determined from the compatible

There are SoCs that use the same FIFO depth for all the instances of the
SPI IP. See the fifo_lvl_mask defined for gs101 for example:
.fifo_lvl_mask = { 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f,
0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f},

Instead of specifying the FIFO depth with the same value for all 16
nodes in this case, allow such SoCs to infer the FIFO depth from the
compatible. There are other SoCs than can benefit of this, see:
{gs101, fsd, exynos850, s3c641, s3c2443}_spi_port_config.

The FIFO depth inferred from the compatible has a higher precedence than
the one that might be specified via device tree, the driver shall know
better.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-7-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: retrieve the FIFO depth from the device tree

There are SoCs that configure different FIFO depths for their instances
of the SPI IP. See the fifo_lvl_mask defined for exynos4_spi_port_config
for example:
.fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
The first instance of the IP is configured with 256 bytes FIFOs, whereas
the last two are configured with 64 bytes FIFOs.

Instead of mangling with the .fifo_lvl_mask and its dependency of the DT
alias ID, allow such SoCs to determine the FIFO depth via the
``fifo-depth`` DT property.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-6-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: determine the fifo depth only once

Determine the FIFO depth only once, at probe time.
``sdd->fifo_depth`` can be set later on with the FIFO depth
specified in the device tree.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-5-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: allow full FIFO masks

The driver is wrong because is using partial register field masks for the
SPI_STATUS.{RX, TX}_FIFO_LVL register fields.

We see s3c64xx_spi_port_config.fifo_lvl_mask with different values for
different instances of the same IP. Take s5pv210_spi_port_config for
example, it defines:
.fifo_lvl_mask = { 0x1ff, 0x7F },

fifo_lvl_mask is used to determine the FIFO depth of the instance of the
IP. In this case, the integrator uses a 256 bytes FIFO for the first SPI
instance of the IP, and a 64 bytes FIFO for the second instance. While
the first mask reflects the SPI_STATUS.{RX, TX}_FIFO_LVL register
fields, the second one is two bits short. Using partial field masks is
misleading and can hide problems of the driver's logic.

Allow platforms to specify the full FIFO mask, regardless of the FIFO
depth.

Introduce {rx, tx}_fifomask to represent the SPI_STATUS.{RX, TX}_FIFO_LVL
register fields. It's a shifted mask defining the field's length and
position. We'll be able to deprecate the use of @rx_lvl_offset, as the
shift value can be determined from the mask. The existing compatibles
shall start using {rx, tx}_fifomask so that they use the full field mask
and to avoid shifting the mask to position, and then shifting it back to
zero in the {TX, RX}_FIFO_LVL macros.

@rx_lvl_offset will be deprecated in a further patch, after we have the
infrastructure to deprecate @fifo_lvl_mask as well.

No functional change intended.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-4-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: define a magic value

Define a magic value, it will be used in the next patch as well.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240216070555.2483977-3-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: add support for google,gs101-spi

Add support for GS101 SPI. GS101 integrates 16 SPI nodes, all with 64
bytes FIFOs. GS101 allows just 32 bit register accesses, otherwise a
Serror Interrupt is raised. Do the write reg accesses in 32 bits.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207111516.2563218-5-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: add s3c64xx_iowrite{8,16}_32_rep accessors

Allow SoCs that require 32 bits register accesses to write data in
chunks of 8 or 16 bits. One SoC that requires 32 bit register accesses
is the google gs101. The operation is rare, thus open code it in the
driver rather than making it generic (through asm-generic/io.h).

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207111516.2563218-4-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: prepare for a different flavor of iowrite rep

There are SoCs (gs101) that allow only 32 bit register accesses. As the
requirement is rare enough, for those SoCs we'll open code in the driver
some s3c64xx_iowrite{8,16}_32_rep() accessors. Prepare for such addition.

Suggested-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20240207111516.2563218-3-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: drop a superfluous bitwise NOT operation

val &= ~mask;
val |= mask;

is equivalent to:
val |= mask;

Drop the superfluous bitwise NOT operation.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-18-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: remove duplicated definition

S3C64XX_SPI_TRAILCNT brings no benefit in terms of name over
S3C64XX_SPI_MAX_TRAILCNT. Remove the duplicated definition.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-17-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: downgrade dev_warn to dev_dbg for optional dt props

"samsung,spi-src-clk" and "num-cs" are optional dt properties. Downgrade
the message from warning to debug message.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-16-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: drop blank line between declarations

Drop the blank line and move the logical operation in the body of the
function rather than in initialization list.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-15-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: return ETIMEDOUT for wait_for_completion_timeout()

ETIMEDOUT is more specific than EIO, use it for
wait_for_completion_timeout().

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-14-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: rename prepare_dma() to s3c64xx_prepare_dma()

Don't monopolize the name. Prepend the driver prefix to the function
name.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-13-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: propagate the dma_submit_error() error code

DMA submit should just add the dma descriptor to a queue, without firing
it. EIO is misleading and hides what happens in DMA. Propagate the
dma_submit_error() error code, don't overwrite it.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-12-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: check return code of dmaengine_slave_config()

Check the return code of dmaengine_slave_config().

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-11-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: move common code outside if else

Move common code outside if else to avoid code duplication.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-10-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: remove else after return

Else case is not needed after a return, remove it.

Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-9-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: remove unneeded (void *) casts in of_match_table

of_device_id::data is an opaque pointer. No explicit cast is needed.
Remove unneeded (void *) casts in of_match_table.

Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-8-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: fix typo, s/configuartion/configuration

Fix typo, s/configuartion/configuration.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-7-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: avoid possible negative array index

The platform id is used as an index into the fifo_lvl_mask array.
Platforms can come with a negative device ID, PLATFORM_DEVID_NONE (-1),
thus we risked a negative array index. Catch such cases and fail to
probe.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-6-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: explicitly include <linux/types.h>

The driver uses u32 and relies on an implicit inclusion of
<linux/types.h>.

It is good practice to directly include all headers used, it avoids
implicit dependencies and spurious breakage if someone rearranges
headers and causes the implicit include to vanish.

Include the missing header.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-5-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: explicitly include <linux/bits.h>

The driver uses GENMASK() but does not include <linux/bits.h>.

It is good practice to directly include all headers used, it avoids
implicit dependencies and spurious breakage if someone rearranges
headers and causes the implicit include to vanish.

Include the missing header.

Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-4-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: explicitly include <linux/io.h>

The driver uses readl() but does not include <linux/io.h>.

It is good practice to directly include all headers used, it avoids
implicit dependencies and spurious breakage if someone rearranges
headers and causes the implicit include to vanish.

Include the missing header.

Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-3-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: sort headers alphabetically

Sorting headers alphabetically helps locating duplicates,
and makes it easier to figure out where to insert new headers.

Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-2-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Add Exynos850 support

Add SPI port configuration for Exynos850 SoC. It has 3 USI blocks which
can be configured in SPI mode:

* spi_0: BLK_PERI_SPI_0 (0x13940000)
* spi_1: BLK_ALIVE_USI_CMGP00 (0x11d00000)
* spi_2: BLK_ALIVE_USI_CMGP01 (0x11d20000)

SPI FIFO depth is 64 bytes for all those SPI blocks, so the
.fifo_lvl_mask value is set to 0x7f. All blocks have DIV_4 as the
default internal clock divider, and an internal loopback mode to run
a loopback test.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://msgid.link/r/20240120012948.8836-6-semen.protsenko@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Extract FIFO depth calculation to a dedicated macro

Simplify the code by extracting all cases of FIFO depth calculation into
a dedicated macro. No functional change.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://msgid.link/r/20240120170001.3356-1-semen.protsenko@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: switch to use modern name

Change legacy name master/slave to modern name host/target or controller.

No functional changed.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20230818093154.1183529-17-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Clean up redundant dev_err_probe()

Referring to platform_get_irq()'s definition, the return value has
already been checked if ret < 0, and printed via dev_err_probe().
Calling dev_err_probe() one more time outside platform_get_irq()
is obviously redundant.

Removing dev_err_probe() outside platform_get_irq() to clean up
above problem.

Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230727131635.2898051-1-chenjiahao16@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: s3c64xx: Use devm_platform_get_and_ioremap_resource()

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Link: https://lore.kernel.org/r/20230706032727.9180-7-frank.li@vivo.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: clear loopback bit after loopback test

When SPI loopback transfer is performed, S3C64XX_SPI_MODE_SELF_LOOPBACK
bit still remained. It works as loopback even if the next transfer is
not spi loopback mode.
If not SPI_LOOP, needs to clear S3C64XX_SPI_MODE_SELF_LOOPBACK bit.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Fixes: ffb7bcd3b27e ("spi: s3c64xx: support loopback mode")
Reviewed-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20230711082020.138165-1-jaewon02.kim@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Use dev_err_probe()

Simplify the code by using dev_err_probe() instead of dev_err()
and 'return'.

Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230606012051.2139333-3-andi.shyti@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Use the managed spi master allocation function

Use devm_spi_alloc_master() and get rid of one goto error path

Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230606012051.2139333-2-andi.shyti@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Use devm_clk_get_enabled()

Replace the tuple devm_clk_get()/clk_prepare_enable() with the
single function devm_clk_get_enabled().

Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230531205550.568340-1-andi.shyti@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Disable IRQ mode when using DMA

Fixing the problem of enabling DMA mode and IRQ mode at the same time.
In this case, a value of more than 6bits is written to RDY_LVL, it can
cause an invasion of other registers, potentially leading to SPI
transfer failure.

Fixes: 1ee806718d5e ("spi: s3c64xx: support interrupt based pio mode")
Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org
Link: https://lore.kernel.org/r/20230510113942.89994-1-jaewon02.kim@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org

spi: s3c64xx: support interrupt based pio mode

Support interrupt based pio mode to optimize cpu usage.
When transmitting data size is larget than 32 bytes, operates with
interrupt based pio mode.

By using the FIFORDY INT, an interrupt can be triggered when
the desired size of data has been received. Using this, we can support
interrupt based pio mode.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com
Link: https://lore.kernel.org/r/20230502062813.112434-4-jaewon02.kim@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org

spi: s3c64xx: add sleep during transfer

In polling mode, the status register is continuously read to check data
transfer completion. It can cause excessive CPU usage.
To reduce this, we can calculate the transfer time and put the sleep during
transfer.

When test on ExynosAuto9 SADK board, throughput remained the same, but
100% CPU utilization decreased to 40%.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org
Link: https://lore.kernel.org/r/20230502062813.112434-3-jaewon02.kim@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org

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: 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: s3c64xx: 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/20230303172041.2103336-63-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Fix large transfers with DMA

The COUNT_VALUE in the PACKET_CNT register is 16-bit so the maximum
value is 65535. Asking the driver to transfer a larger size currently
leads to the DMA transfer timing out. Implement ->max_transfer_size()
and have the core split the transfer as needed.

Fixes: 230d42d422e7 ("spi: Add s3c64xx SPI Controller driver")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/r/20220927112117.77599-5-vincent.whitchurch@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: correct dma_chan pointer initialization

Use NULL for dma channel pointer initialization instead of plain integer.

sparse warnings: (new ones prefixed by >>)
>> drivers/spi/spi-s3c64xx.c:387:34: sparse: sparse: Using plain integer as NULL pointer
drivers/spi/spi-s3c64xx.c:388:34: sparse: sparse: Using plain integer as NULL pointer

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 82295bc0d192 ("spi: s3c64xx: move dma_release_channel to unprepare")
Fixes: f52b03c70744 ("spi: s3c64xx: requests spi-dma channel only during data transfer")
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220808004851.25122-1-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: add spi port configuration for Exynos Auto v9 SoC

Add exynosautov9 spi port configuration. It supports up to 12 spis so
MAX_SPI_PORTS should be increased from 6 to 12.
It has DIV_4 as the default internal clock divider and an internal
loopback mode to run a loopback test.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220629102304.65712-5-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: support custom value of internal clock divider

Modern exynos SoCs such as Exynos Auto v9 have different internal clock
divider, for example "4". To support this internal value, this adds
clk_div of the s3c64xx_spi_port_config and assign "2" as the default
value to existing s3c64xx_spi_port_config.

Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220629102304.65712-3-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: support loopback mode

Modern exynos SoCs can support self loopback mode via setting BIT(3) of
MODE_CFG register. Previous SoCs don't have the bit so we need to add
has_loopback field in the s3c64xx_spi_port_config. Exynos Auto v9 SoC
has the bit and it will define the field to "true".
When it is set, SPI_LOOP mode will be marked.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220629102304.65712-2-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: move dma_release_channel to unprepare

This fixes the sequence of dma_release_channel.
Since commit f52b03c70744 ("spi: s3c64xx: requests spi-dma channel only
during data transfer"),
dma_release_channel has been located in the s3c64xx_spi_transfer_one
but this makes invalid return of can_dma callback.
__spi_unmap_msg will check whether the request is requested by dma or
not via can_dma callback. When it is calling to check it, the channels
will be already released at the end of s3c64xx_spi_transfer_one so the
callback function will return always "false". So, they can't be unmapped
from __spi_unmap_msg call. To fix this, we need to add
unprepare_transfer_hardware callback and move the dma_release_channel
from s3c64xx_spi_transfer_one to there.

Fixes: f52b03c70744 ("spi: s3c64xx: requests spi-dma channel only during data transfer")
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220627013845.138350-1-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: constify fsd_spi_port_config

All struct s3c64xx_spi_port_config should be const.

Fixes: 4ebb15a15799 ("spi: s3c64xx: Add spi port configuration for Tesla FSD SoC")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220627094541.95166-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: set pointers to null using NULL rather than 0

There are pointers being set to null using use. Use NULL instead.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Link: https://lore.kernel.org/r/20220612203428.2754823-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Return true/false (not 1/0) from bool function

Return boolean values ("true" or "false") instead of 1 or 0 from bool
function.

As reported by coccicheck:
./drivers/spi/spi-s3c64xx.c:385:9-10: WARNING: return of 0/1 in function
's3c64xx_spi_can_dma' with return type bool

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220609071250.59509-1-yang.lee@linux.alibaba.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Fix spelling mistake "hannel" -> "channel"

There is a spelling mistake in a dev_err message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Link: https://lore.kernel.org/r/20220608081912.2083086-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: requests spi-dma channel only during data transfer

Current s3c64xx SPI driver acquires DMA channel during driver
probe and holds on it even when channels are not used
(no DMA transfer). This is a problem especially when all the
DMA channels are exhausted (as other IPs on the same DMA
controller also acquires DMA channel) and if a new IP/Device
requests for a DMA channel (on the same DMA controller), it won’t
get DMA channel allocated.
The said issue can be avoided if s3c64xx driver request and
release DMA channel before and after data transfer. Let’s modify
the driver to request and release DMA channel before and after
DMA mode data transfer.

Signed-off-by: Adithya K V <adithya.kv@samsung.com>
Link: https://lore.kernel.org/r/20220524140132.59300-1-adithya.kv@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Add spi port configuration for Tesla FSD SoC

Add compatible and port configuration for spi controller
for Tesla Full Self-Driving SoC.

Cc: linux-fsd@tesla.com
Signed-off-by: Aswani Reddy <aswani.reddy@samsung.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Link: https://lore.kernel.org/r/20220308121640.27344-2-alim.akhtar@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Allow controller-data to be optional

The Samsung SoC SPI driver requires to provide controller-data node
for each of SPI peripheral device nodes. Make this controller-data node
optional, so DTS could be simpler.

Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220124082347.32747-5-krzysztof.kozlowski@canonical.com

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: constify driver/match data

The match data (struct s3c64xx_spi_port_config) stored in of_device_id
and platform_device_id tables is not modified by the driver and can be
handled entirely in a const-way to increase the code safety.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sylwester Nawrocki <snawrocki@kernel.org>
Link: https://lore.kernel.org/r/20210414203343.203119-3-krzysztof.kozlowski@canonical.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: correct kerneldoc of s3c64xx_spi_port_config

Correct the name of s3c64xx_spi_port_config structure in kerneldoc:

drivers/spi/spi-s3c64xx.c:154: warning:
expecting prototype for struct s3c64xx_spi_info. Prototype was for struct s3c64xx_spi_port_config instead

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sylwester Nawrocki <snawrocki@kernel.org>
Link: https://lore.kernel.org/r/20210414203343.203119-2-krzysztof.kozlowski@canonical.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: simplify getting of_device_id match data

Use of_device_get_match_data() to make the code slightly smaller and to
remove the of_device_id table forward declaration.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sylwester Nawrocki <snawrocki@kernel.org>
Link: https://lore.kernel.org/r/20210414203343.203119-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Turn on interrupts upon resume

s3c64xx_spi_hwinit() disables interrupts. In s3c64xx_spi_probe() after
calling s3c64xx_spi_hwinit() they are enabled with the following call.

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-10-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Increase transfer timeout

Increase timeout by 30 ms for some wiggle room and set the minimum value
to 100 ms. This ensures a non-zero value for short transfers which
may take less than 1 ms. The timeout value does not affect
performance because it is used with a completion.

Similar formula is used in other drivers e.g. sun4i, sun6i.

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-9-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Ensure cur_speed holds actual clock value

Make sure the cur_speed value used in s3c64xx_enable_datapath()
to configure DMA channel and in s3c64xx_wait_for_*() to calculate the
transfer timeout is set to the actual value of (half) the clock speed.

Don't change non-CMU case, because no frequency calculation errors have
been reported.

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Suggested-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-8-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Fix doc comment for struct s3c64xx_spi_driver_data

Remove descriptions for non-existent fields and fix indentation.

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-7-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Rename S3C64XX_SPI_SLAVE_* to S3C64XX_SPI_CS_*

Rename S3C64XX_SPI_SLAVE_* to S3C64XX_SPI_CS_* to match documentation.

Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201002122243.26849-6-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Report more information when errors occur

Report amount of pending data when a transfer stops due to errors.

Report if DMA was used to transfer data and print the status code.

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-5-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Check return values

Check return values in prepare_dma() and s3c64xx_spi_config() and
propagate errors upwards.

Fixes: 788437273fa8 ("spi: s3c64xx: move to generic dmaengine API")
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-4-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3s64xx: Add S3C64XX_SPI_QUIRK_CS_AUTO for Exynos3250

Fix issues with DMA transfers bigger than 512 bytes on Exynos3250. Without
the patches such transfers fail.

The vendor kernel for ARTIK5 handles CS in a simmilar way.

Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201002122243.26849-3-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: swap s3c64xx_spi_set_cs() and s3c64xx_enable_datapath()

Fix issues with DMA transfers bigger than 512 bytes on Exynos3250. Without
the patches such transfers fail to complete. This solution to the problem
is found in the vendor kernel for ARTIK5 boards based on Exynos3250.

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-2-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Add missing entries for structs 's3c64xx_spi_dma_data' and 's3c64xx_spi_dma_data'

Fixes the following W=1 kernel build warning(s):

drivers/spi/spi-s3c64xx.c:150: warning: Function parameter or member 'quirks' not described in 's3c64xx_spi_port_config'
drivers/spi/spi-s3c64xx.c:150: warning: Function parameter or member 'clk_ioclk' not described in 's3c64xx_spi_port_config'
drivers/spi/spi-s3c64xx.c:189: warning: Function parameter or member 'pdev' not described in 's3c64xx_spi_driver_data'
drivers/spi/spi-s3c64xx.c:189: warning: Function parameter or member 'rx_dma' not described in 's3c64xx_spi_driver_data'
drivers/spi/spi-s3c64xx.c:189: warning: Function parameter or member 'tx_dma' not described in 's3c64xx_spi_driver_data'
drivers/spi/spi-s3c64xx.c:189: warning: Function parameter or member 'port_conf' not described in 's3c64xx_spi_driver_data'
drivers/spi/spi-s3c64xx.c:189: warning: Function parameter or member 'port_id' not described in 's3c64xx_spi_driver_data'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Andi Shyti <andi@etezian.org>
Cc: Jaswinder Singh <jassi.brar@samsung.com>
Cc: linux-samsung-soc@vger.kernel.org
Link: https://lore.kernel.org/r/20200717135424.2442271-8-lee.jones@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Use dma_request_chan() directly for channel request

dma_request_slave_channel_reason() is:
#define dma_request_slave_channel_reason(dev, name) \
dma_request_chan(dev, name)

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Andi Shyti <andi@etezian.org>
Link: https://lore.kernel.org/r/20191113094256.1108-8-peter.ujfalusi@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Fix system resume support

Since Linux v4.10 release (commit 1d9174fbc55e "PM / Runtime: Defer
resuming of the device in pm_runtime_force_resume()"),
pm_runtime_force_resume() function doesn't runtime resume device if it was
not runtime active before system suspend. Thus, driver should not do any
register access after pm_runtime_force_resume() without checking the
runtime status of the device. To fix this issue, simply move
s3c64xx_spi_hwinit() call to s3c64xx_spi_runtime_resume() to ensure that
hardware is always properly initialized. This fixes Synchronous external
abort issue on system suspend/resume cycle on newer Exynos SoCs.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: s3c64xx: samsung: Remove support for Exynos5440

The Exynos5440 is not actively developed, there are no development
boards available and probably there are no real products with it.
Remove wide-tree support for Exynos5440.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Allow higher transfer lengths in polling IO mode

Some variants of the SPI controller have no DMA support, in such case
SPI transfers longer than the FIFO length are not currently properly
handled by the driver. Fix it by doing multiple transfers in the
s3c64xx_spi_transfer_one() function if the SPI transfer length exceeds
the FIFO size.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Use local variable for FIFO length

More references to fifo_len are added in subsequent patch.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Add missing s3c64xx_ prefix to function names

Add a s3c64xx_ prefix to remaining generic function names so it is clear
the code is part of the driver when grepping or looking at debug logs.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Drop unused enable_datapath() function argument

The spi pointer argument is not used now so remove it.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Fix indentation in the register offset definitions

Change indentation so register address offset and register bit definitions
are aligned to same column.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Do not ignore timeout errors in polling I/O mode

Currently timeout errors in polling I/O mode transfer are silently ignored.
Fix it by returning an error when we time out waiting on the RX FIFO level
to reach the transfer length.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Remove unused s3c64xx_spi_hwinit() function argument

The channel argument is not used and anyway it could be retrieved from
the passed driver data structure.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-s3c64xx: Remove unused driver data structure tgl_spi field

The tgl_spi pointer is now unused so remove it.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.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>

spi: s3c64xx: remove redundant pointer sci

The pointer sci is assigned but never read, hence it is redundant
and can be removed. Cleans up clang warning:

drivers/spi/spi-s3c64xx.c:791:2: warning: Value stored to 'sci' is
never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: fix inconsistency between binding and driver

Commit a92e7c3d82a1 ("spi: s3c64xx: consider the case when the CS
line is not connected") introduced an inconsistency between the
binding, where the disconnected CS line was marked as
'no-cs-readback', and the driver.

The driver is erroneously checking for that attribute with
property name of 'broken-cs'.

Check for 'no-cs-readback' in the driver as well.

Fixes: a92e7c3d82a1 ("spi: s3c64xx: consider the case when the CS line is not connected")
Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: s3c64xx: potential oops on probe error

We accidentally mixed up freeing the rx and tx channels which would a
leak and an oops.

Fixes: 3d63a47a380a ("spi: s3c64xx: Don't request/release DMA channels for each SPI transfer")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Don't request/release DMA channels for each SPI transfer

Requesting a DMA channel might be a time consuming operation, so there is
no need to acquire and release DMA channel for each SPI transfer.
DMA channels can be requested during driver probe and kept all the time,
also because there are no shared nor dynamically allocated channels on
Samsung S3C/S5P/Exynos platforms.

While moving dma_requrest_slave_channel calls, lets switch to
dma_request_slave_channel_reason(), which returns error codes on failure,
which can be properly propagated to the caller (this for example defers
SPI probe when DMA controller is not yet available).

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Tested-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Do not use platform_data for DMA parameters

All related platforms use either devicetree or the DMA slave
map API for mapping DMA channels to DMA slaves so we can now
stop using platform_data for passing DMA details.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Andi Shyti <andi.shyti@samsung.com>
Tested-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

spi: s3c64xx: restore removed comments

Patch a9e93e8 has erroneously removed some comments which are
important to understand why the bus frequency is multiplied by
two during the spi transfer.

Reword the previous comment to a more appropriate message.

Suggested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: add Exynos5433 compatible for ioclk handling

The new compatible is related to the Samsung Exynos5433 SoC. The
difference between the previous is that in the exynos5433 the SPI
controller is driven by three clocks instead of only one.

The new clock (ioclk) is controlling the input/output clock
whenever the controller is slave or master.

The presence of the clock line is detected from the compatibility
structure (exynos5433_spi_port_config) as a boolean value.

The probe function checks whether the ioclk is present and if so,
it acquires.

The runtime suspend and resume functions will handle the clock
enabling and disabling as well.

Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Michael Turquette <mturquette@baylibre.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: use error code from clk_prepare_enable()

If clk_prepare_enable() fails do not return -EBUSY but use the
value provided by the function itself.

Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Michael Turquette <mturquette@baylibre.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: rename goto labels to meaningful names

The goto labels of the style of

err4:
err3:
err2:
err1:

are complex to insert in between new errors without renaming all
the goto statements. Replace the errX naming style to meaningful
names in order to make it easier to insert new goto exit points.

Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: fix reference leak to master in s3c64xx_spi_remove()

Once a spi_master_get() call succeeds, we need an additional
spi_master_put() call to free the memory, otherwise we will
leak a reference to master. Fix by removing the unnecessary
spi_master_get() call.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: do not disable the clock while configuring the spi

When the clock is coming from the cmu it is not required to be
disabled and then re-enabled in order to change the rate.

Besides, some exynos chipsets (e.g. exynos5433) do not deliver
any to the SFR if one from the pclk ("spi" in this case) or sclk
("busclk") is disabled.

Remove the clock disabling/enabling to avoid falling into this
situation.

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

spi: s3c64xx: indent an if statement

It generates a static checker warning if an if statement isn't indented.
I think the code is fine except for the white space issue.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: simplify if statement in prepare_transfer function

The whole function is inside an 'if' statement
("!is_polling(sdd)").

Check the opposite of that statement at the beginning and exit,
this way we can have one level less of indentation.

Remove the goto paths as they are redundant.

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

spi: s3c64xx: do not configure the device twice

At the start of the transfer, the spi_config function is called
twice, the first time when the 3c64xx_spi_prepare_message is
called and the second time with the s3c64xx_spi_transfer_one,
both called from the spi framework.

Remove the first call at the prepare message because in that
point we don't have the imformation about "bit per word" and
frequency.

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

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: group the CS signalling writes in a single function

To enable/disable the CS line, the driver performs a writel in
the S3C64XX_SPI_SLAVE_SEL registers. Group the register's
configuration in a single function.

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

spi: s3c64xx: Remove unused platform_device_id entries

s5pv210 and exynos4 are now DT only platforms hence these
entries can now be safely removed from the match table.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@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: Use transfer speed unconditionally

SPI core validates the transfer speed and defaults to spi->max_speed_hz in
case the transfer speed is not set.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: replace clock disabling with runtime PM suspend call in remove function

Simplify s3c64xx_spi_remove by replacing the clock disabling with calling
runtime PM suspend which does the same.
Waking up the device if it was suspended wouldn't be strictly needed
for this driver but using pm_runtime_get_sync is cleaner and makes
s3c64xx_spi_remove more consistent with the runtime PM handling in
s3c64xx_spi_setup.

pm_runtime_force_suspend does most of the work for us:
disabling the clocks, disabling runtime PM and setting it to
"suspended" state.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: simplify suspend / resume handlers

The runtime PM suspend / resume handlers take care of the enabling/
disabling the clocks already. Therefore replace the duplicated
clock handling with pm_runtime_force_suspend/resume.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: extend driver to make full use of runtime PM autosuspend

Extend the driver to make full use of runtime PM autosuspend.
Before only the SPI core was instructed to use autosuspend
by setting master->auto_runtime_pm. Nevertheless due to the missing
pm_runtime_use_autosuspend call autosuspend wasn't active.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: clean up runtime PM if driver registration fails

Fix missing runtime PM cleanup if driver registration fails.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: print fifo size on probe.

Printing the FIFO depth does not add much noise in the log and can be useful
for debugging transfer issues.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: Constify platform_device_id

The platform_device_id is not modified by the driver and core uses it as
const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: fix compiler warning in spi-s3c64xx

The Exynos 7 arm64 support now allows the S3C64xx SPI driver to be
compiled into an ARM64 kernel, so the cast from the [rt]x_dmach int
variable to a void* in this driver now triggers a warning.
Add a long cast to silence the compiler.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Remove FSF mailing addresses

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Replace CONFIG_PM_RUNTIME with CONFIG_PM

After commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so #ifdef blocks
depending on CONFIG_PM_RUNTIME may now be changed to depend on
CONFIG_PM.

Replace CONFIG_PM_RUNTIME with CONFIG_PM everywhere under
drivers/spi/.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mark Brown <broonie@kernel.org>

spi/s3c64xx: Remove redundant runtime PM management

The device already asks the core to hold a runtime PM reference while it
is active so it is redundant to open code that in the driver itself.

Signed-off-by: Mark Brown <broonie@kernel.org>

spi: s3c64xx: add support for exynos7 SPI controller

Exynos7 SPI controller supports only the auto Selection of
CS toggle mode and Exynos7 SoC includes six SPI controllers.
Add support for these changes in Exynos7 SPI controller driver.

Signed-off-by: Padmavathi Venna <padma.v@samsung.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: s3c64xx: use the generic SPI "cs-gpios" property

The s3c64xx SPI driver uses a custom DT binding to specify
the GPIO used to drive the chip select (CS) line instead of
using the generic "cs-gpios" property already defined in:
Documentation/devicetree/bindings/spi/spi-bus.txt.

It's unfortunate that drivers are not using standard bindings
and creating custom ones instead but in most cases this can't
be changed without breaking Device Tree backward compatibility.

But in the case of this driver, its DT binding has been broken
for more than a year. Since after commit (dated June, 21 2013):

3146bee ("spi: s3c64xx: Added provision for dedicated cs pin")

DT backward compatibility was broken and nobody noticed until
now when the commit was reverted. So it seems to be safe to
change the binding to use the standard SPI "cs-gpios" property
instead of using a custom one just for this driver.

This patch also allows boards that don't use a GPIO pin for the
CS to work with the driver since the SPI core will take care of
setting spi->cs_gpio to -ENOENT if a board wants to use the built
in CS instead of a GPIO as explained in the SPI bus DT binding:
Documentation/devicetree/bindings/spi/spi-bus.txt.

For non-DT platforms, spi->cs_gpio will be set to -ENOENT as well
unless they specify a GPIO pin in their platform data. So both
native and GPIO chip select is also supported for legacy boards.

The above use case was what motivated commit 3146bee which broke
the DT binding backward compatibility in the first place.

Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
[javier.martinez@collabora.co.uk: split changes and improve commit message]
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Revert "spi: s3c64xx: Added provision for dedicated cs pin"

This reverts commit 3146beec21b64f4551fcf0ac148381d54dc41b1b.

This commit resulted in a DT backward compatibility breakage.

Some devices use the native chip select (CS) instead of a GPIO
pin to drive the CS line. But the SPI driver made it mandatory
to specify a GPIO pin in the SPI device node controller-data.
So, using the built-in CS was not possible with the driver.

Commit 3146bee tried to fix that by adding a "cs-gpio" property
which could be defined in the SPI device node to make the driver
request the GPIO from the controller-data node.

Unfortunately that changed the old DT binding semantics since
now it's mandatory to have the "cs-gpio" property defined in
the SPI device node in order to use a GPIO pin to drive the CS.

As an example, a SPI device was defined before the commit with:

spi@12d20000 {
slave-node@0 {
controller-data {
cs-gpio = <&gpb1 2 0>;
}
}
}

and after the commit, the following DTS snippet must be used:

spi@12d20000 {
cs-gpio;
slave-node@0 {
controller-data {
cs-gpio = <&gpb1 2 0>;
}
}
}

So, after commit 3146bee the driver does not look for the GPIO
by default and it only looks for it if the top level "cs-gpio"
property is defined while the default used to be the opposite.
To always request the GPIO defined in the controller-data node.

This means that old FDT that of course didn't have this added
"cs-gpio" DT property in the SPI node broke after this change.

The offending commit can't be reverted cleanly since more than
a year have passed and other changes were made in the meantime
but this patch partially reverts the driver to it's original
state so old FDT can work again.

This patch will break Device Trees that were relying on the new
behavior of course but the patch should be reverted because:

a) There aren't DTS in mainline that use this new property.
b) They were relying on a behavior that broke DT compatibility.
c) The new binding is awkard, needing two properties with the
same name (cs-gpio) on different nodes is confusing at least.
d) The new property was not added to the DT binding doc:
Documentation/devicetree/bindings/spi/spi-samsung.txt

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: remove s5pc100 related spi codes

This patch removes sp5c100 related spi because of no more support
s5pc100 SoC.

Cc: Mark Brown <broonie@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: remove s5p64x0 related spi codes

This patch removes s5p64x0 related spi because of no more support for
s5p64x0 SoCs. Meanwhile, cleanup SPI DT bindings for s5p6440-spi, it
should be s5p64x0-spi instead.

Cc: Mark Brown <broonie@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: remove unnecessary OOM messages

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.

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

spi: Remove unneeded include of linux/workqueue.h

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

spi: s3c64xx: Let spi core handle validating transfer length

spi core will handle validating transfer length since commit 4d94bd21b333
"spi: core: Validate length of the transfers in message".
So remove the same checking in this driver.

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

spi/s3c64xx: Remove code no longer needed as a result of S3C_DMA removal

Remove functions that only had an effect when using S3C_DMA and inline
dmaengine_terminate_all() since it's pointless to have a function which
expands to a single function call.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Remove S3C_DMA support

All the platforms which use the old S3C_DMA API have now been converted to
dmaengine so we can remove the legacy code from the driver, simplifying
maintenance.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Use core DMA mapping code with dmaengine

When using dmaengine allow the core to do the DMA mapping. We still need
local mapping code for the non-dmaengine case so this doesn't save us
anything for now.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi: Make core DMA mapping functions generate scatterlists

We cannot unconditionally use dma_map_single() to map data for use with
SPI since transfers may exceed a page and virtual addresses may not be
provided with physically contiguous pages. Further, addresses allocated
using vmalloc() need to be mapped differently to other addresses.

Currently only the MXS driver handles all this, a few drivers do handle
the possibility that buffers may not be physically contiguous which is
the main potential problem but many don't even do that. Factoring this
out into the core will make it easier for drivers to do a good job so if
the driver is using the core DMA code then generate a scatterlist
instead of mapping to a single address so do that.

This code is mainly based on a combination of the existing code in the MXS
and PXA2xx drivers. In future we should be able to extend it to allow the
core to concatenate adjacent transfers if they are compatible, improving
performance.

Currently for simplicity clients are not allowed to use the scatterlist
when they do DMA mapping, in the future the existing single address
mappings will be replaced with use of the scatterlist most likely as
part of pre-verifying transfers.

This change makes it mandatory to use scatterlists when using the core DMA
mapping so update the s3c64xx driver to do this when used with dmaengine.
Doing so makes the code more ugly but it is expected that the old s3c-dma
code can be removed very soon.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Split wait_for_xfer() into PIO and DMA versions

There is no meaningful code sharing between the PIO and DMA variants
(just the timeout calculation) so in order to make the code easier to
work with split the two cases.

Looking at the code it is not clear how the PIO version works for large
transmits, greater than FIFO size is only handled for RX.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Remove unused /CS GPIO management

The GPIO enable and disable is done in the core so does not need to be
replicated in the driver, delete the unneeded code. enable_cs() was not
referenced at all.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Correct indentation

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Remove duplicate code to clear S3C64XX_SPI_SLAVE_SEL register

Signed-off-by: Axel Lin <axel.lin@ingics.com>
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/s3c64xx: Fix doubled clock disable on suspend

Fix doubled clock disable and unprepare during PM suspend which triggered
the warnings:

WARNING: at drivers/clk/clk.c:800 clk_disable+0x18/0x24()
Modules linked in:
CPU: 0 PID: 1745 Comm: sh Not tainted 3.10.14-01211-ge2549bb-dirty #62
[<c0015980>] (unwind_backtrace+0x0/0x138) from [<c0012a44>] (show_stack+0x10/0x14)
[<c0012a44>] (show_stack+0x10/0x14) from [<c0022818>] (warn_slowpath_common+0x4c/0x68)
[<c0022818>] (warn_slowpath_common+0x4c/0x68) from [<c0022850>] (warn_slowpath_null+0x1c/0x24)
[<c0022850>] (warn_slowpath_null+0x1c/0x24) from [<c036e274>] (clk_disable+0x18/0x24)
[<c036e274>] (clk_disable+0x18/0x24) from [<c02d5f78>] (s3c64xx_spi_suspend+0x28/0x54)
[<c02d5f78>] (s3c64xx_spi_suspend+0x28/0x54) from [<c02b3a54>] (platform_pm_suspend+0x2c/0x5c)
[<c02b3a54>] (platform_pm_suspend+0x2c/0x5c) from [<c02b8a30>] (dpm_run_callback+0x44/0x7c)
[<c02b8a30>] (dpm_run_callback+0x44/0x7c) from [<c02b8b70>] (__device_suspend+0x108/0x300)
[<c02b8b70>] (__device_suspend+0x108/0x300) from [<c02ba4e0>] (dpm_suspend+0x54/0x208)
[<c02ba4e0>] (dpm_suspend+0x54/0x208) from [<c0066bcc>] (suspend_devices_and_enter+0x98/0x458)
[<c0066bcc>] (suspend_devices_and_enter+0x98/0x458) from [<c0067150>] (pm_suspend+0x1c4/0x25c)
[<c0067150>] (pm_suspend+0x1c4/0x25c) from [<c0066044>] (state_store+0x6c/0xbc)
[<c0066044>] (state_store+0x6c/0xbc) from [<c0203290>] (kobj_attr_store+0x14/0x20)
[<c0203290>] (kobj_attr_store+0x14/0x20) from [<c0157530>] (sysfs_write_file+0xfc/0x164)
[<c0157530>] (sysfs_write_file+0xfc/0x164) from [<c00fd6b0>] (vfs_write+0xbc/0x1bc)
[<c00fd6b0>] (vfs_write+0xbc/0x1bc) from [<c00fdaf0>] (SyS_write+0x40/0x68)
[<c00fdaf0>] (SyS_write+0x40/0x68) from [<c000ea80>] (ret_fast_syscall+0x0/0x3c)

The clocks may be already disabled before suspending. Check PM runtime
suspend status and disable clocks only if device is not suspended.
During resume do not enable the clocks if device is runtime suspended.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Do not ignore return value of spi_master_resume/suspend

During PM resume and suspend do not ignore the return value of
spi_master_suspend() or spi_master_resume(). Instead pass it further.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Add missing pm_runtime_put on setup fail

pm_runtime_put() wasn't called if clock rate could not be set up in
s3c64xx_spi_setup() leading to invalid count of device pm_runtime usage.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Add missing pm_runtime_set_active() call in probe()

Mark device as PM runtime active during initialization to reflect
actual device power/clocks state. This reduces the enable count for SPI
bus controller gate clock so it can be disabled when the bus controller
is not used.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Use core message handling

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Use prepare_message() and unprepare_message()

This is of very little value in itself but will be useful once the loop
iterating over the transfers is also factored out into the core.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Factor transfer start out of enable/disable_cs()

The hardware level /CS handling is tied to the start of the data path so
is rolled into the same function as we use to manipulate GPIO /CS. In
order to support factoring out the /CS handling into the core separate the
two and explicitly start transfers separately to the /CS handling.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Enable GPIO /CS prior to starting hardware

To help with bisection of future refactoring to share more of the code for
handling a spi_message pull the enabling of GPIO based /CS prior to all
the hardware setup for starting a transfer.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Factor transfer start out of enable/disable_cs()

The hardware level /CS handling is tied to the start of the data path so
is rolled into the same function as we use to manipulate GPIO /CS. In
order to support factoring out the /CS handling into the core separate the
two and explicitly start transfers separately to the /CS handling.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Use core cs_gpio field

Rather than using the driver custom platform data to store the chip select
GPIO use the cs_gpio field provided by the SPI core, supporting future
refectoring.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Remove unused gpios field from driver data

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Check that clock enables succeed on runtime resume

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Flush FIFOs prior to cleaning up transfer

Ensure that the FIFOs are fully drained before we deassert /CS or do any
delays that have been requested in order to ensure that the behaviour
visible on the bus matches that which was requested by the caller.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Ensure runtime PM is enabled prior to registration

Otherwise we may try to start transfers immediately and then fail to
runtime resume the device causing us not to have clocks enabled.

Signed-off-by: Mark Brown <broonie@linaro.org>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

Conflicts:
drivers/spi/spi-s3c64xx.c

spi: s3c64xx: Add missing compatibles

Add compatibles for s3c6410, s5pc100 and s5pc110/s5pv210 boards.

Signed-off-by: Mateusz Krawczuk <m.krawczuk@partner.samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Use managed registration

Also improve the error reporting on failure and remove a duplicate put.
This provides a small code saving.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-s3c64xx: Use module_platform_driver()

subsys_init_call() initializes driver too early.
It's preventing to move DMA channel allocation at the begining
(driver probe).

This patch reduces and simplifies initalization code by
using module_platform_driver() macro.
It's also efficiently delaying driver startup.

Signed-off-by: Lukasz Czerwinski <l.czerwinski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.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>

spi/s3c64xx: Take runtime PM reference even if DMA is not supported

We always need the device to be runtime PM enabled to use it so just skip
the DMA initialisation not the entire prepare when polling.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Use dmaengine_prep_slave_single() to prepare DMA transfers

Since the driver supports only contiguous buffers, there is no need to
manually construct a scatterlist with just a single entry, when there is
a dedicated helper for this purpose.

This patch modifies prepare_dma() function to use available helper instead
of manually creating a scatterlist.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Do not request CS GPIO on subsequent calls to .setup()

Comments in linux/spi/spi.h and observed behavior show that .setup()
callback can be called multiple times without corresponding calls to
.cleanup(), what was incorrectly assumed by spi-s3c64xx driver, leading
to failures trying to request CS GPIO multiple times.

This patch modifies the behavior of spi-s3c64xx driver to request CS
GPIO only on first call to .setup() after last .cleanup().

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Zero dma_slave_config struct in prepare_dma()

Not all fields of dma_slave_config struct are being initialized by
prepare_dma() function, leaving those which are not in undefined state,
which can confuse DMA drivers using them.

This patch adds call to memset() to zero the struct before initializing
a subset of its fields.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Use core for runtime PM

Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: fix casting warning

sdd->ops->request is unsigned int, not unsigned long.
Also, sdd->rx_dma.ch is a 'struct dma_chan *'.
Thus, (void *) is converted to (struct dma_chan *)(unsigned long),
in order to fix possible sparse warnings.

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

spi: s3c64xx: fix printk warnings

Fix the following build warnings when LPAE is enabled:

drivers/spi/spi-s3c64xx.c:1466:2: warning: format '%x' expects argument of type 'unsigned int', but argument 4 has type
'resource_size_t' [-Wformat]
drivers/spi/spi-s3c64xx.c:1466:2: warning: format '%x' expects argument of type 'unsigned int', but argument 5 has type
'resource_size_t' [-Wformat]

Use vsprintf extension %pR to format resource.

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

spi: s3c64xx: fix checkpatch error and warnings

Fix the following checkpatch error and warnings:

ERROR: "(foo*)" should be "(foo *)"
WARNING: line over 80 characters
WARNING: quoted string split across lines

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

spi/s3c64xx: Remove unused message queue

Since the driver has been converted to use the core message pump code
the only use of the messsage queue in the driver is a check to see if
it is empty which will always succeed since nothing ever adds to the
queue. Just remove the queue.

Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: add missing check for polling mode

Due to changes in mainline prior to submission the spi device detection
in polling mode breaks. This revealed the missing check for polling
during dma prepare. This patch adds the missing check.

Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: add missing check for polling mode

After the patch "spi/s3c64xx: Fix non-dmaengine usage"
with commit id 563b444e33810f3120838620c990480304e24e63
submitted by Mark Brown, the spi device detection in polling
mode breaks. This revealed the missing check for polling during
dma prepare. This patch adds the missing check.

Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Rely on the compiler eliminating the OF ID table

This should work with modern compilers, isn't that much of an issue if
it goes wrong and it ensures that the DT-only hardware variants don't
leave unreferenced parameters structures lying around.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Added support for exynos5440 spi

This patch adds support for the exynos5440 spi controller.
The integration of the spi IP in exynos5440 is different from
other SoC's. The I/O pins are no more configured via gpio, they
have dedicated pins.

Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Added provision for dedicated cs pin

The existing driver supports gpio based /cs signal.
For controller's that have one device per controller,
the slave device's /cs signal might be internally controlled
by the chip select bit of slave select register. They are not
externally asserted/deasserted using gpio pin.

This patch adds support for controllers with dedicated /cs pin.
if "cs-gpio" property doesnt exist in a spi dts node, the controller
would treat the /cs pin as dedicated.

Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/s3c64xx: Make wait_for_timeout() function name less generic

Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: added support for polling mode

The 64xx spi driver supports partial polling mode.
Only the last chunk of the transfer length is transferred
or recieved in polling mode.

Some SoC's that adopt this controller might not have have dma
interface. This patch adds support for complete polling mode
and gives flexibity for the user to select poll/dma mode.

Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: s3c64xx: Fix pm_runtime_get_sync() return value check

If the device is already in a runtime PM enabled state
pm_runtime_get_sync() will return 1, so a test for negative
value should be used to check for errors.

Without this patch there are seen errors like:

[ 8.540000] s3c64xx-spi 13930000.spi: Failed to enable device: 1
[ 8.545000] spi_master spi1: failed to prepare transfer hardware

Likely because the driver uses synchronous API to runtime enable
the device and asynchronous one to disable it.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonielinaro.org>
Cc: stable@vger.kernel.org

spi: convert drivers to use bits_per_word_mask

Fill in the recently added spi_master.bits_per_word_mask field in as
many drivers as possible. Make related cleanups, such as removing any
redundant error-checking, or empty setup callbacks.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: remove unnecessary platform_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d0631001288a5974afc0b2a5f568bcdecb4d
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/s3c64xx: Check for errors in dmaengine prepare_transfer()

Don't silently ignore errors, report them.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/s3c64xx: Fix non-dmaengine usage

The multiplatform conversion in commit 788437 (spi: s3c64xx: move to
generic dmaengine API) tested for the use of the Samsung-specific DMA
API with SAMSUNG_DMADEV when in fact S3C_DMA should be used. This
renderd DMA based transfers non-functional on platforms not using
dmaengine.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/s3c64xx: let device core setup the default pin configuration

With device core now able to setup the default pin configuration,
the pin configuration code based on the deprecated Samsung specific
gpio bindings is removed.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Grant Likely <grant.likely@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>

spi/s3c64xx: add CONFIG_PM_SLEEP to suspend/resume functions

Add CONFIG_PM_SLEEP to suspend/resume functions to fix the following
build warning when CONFIG_PM_SLEEP is not selected. This is because
sleep PM callbacks defined by SET_SYSTEM_SLEEP_PM_OPS are only used
when the CONFIG_PM_SLEEP is enabled.

drivers/spi/spi-s3c64xx.c:1362:12: warning: 's3c64xx_spi_suspend' defined but not used [-Wunused-function]
drivers/spi/spi-s3c64xx.c:1381:12: warning: 's3c64xx_spi_resume' defined but not used [-Wunused-function]

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

spi/s3c64xx: Convert to bits_per_word_mask

The core can do the validation for us.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/s3c64xx: modified error interrupt handling and init

The status of the interrupt is available in the status register,
so reading the clear pending register and writing back the same
value will not actually clear the pending interrupts. This patch
modifies the interrupt handler to read the status register and
clear the corresponding pending bit in the clear pending register.

Modified the hwInit function to clear all the pending interrupts.

Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org

spi: spi-s3c64xx.c Remove unused argument.

The pointer to the driver data is never used to get the slave
controller data. We can delete the unused argument from the function.

Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: Remove erroneous __init, __exit and __exit_p() references in drivers

Some of the spi driver module remove hooks were annotated with __exit
and referenced with __exit_p(). Presumably these were supposed to be
__devinit, __devexit and __devexit_p() since __init/__exit for a
probe/remove hook has never been correct. They also got missed during
the big __devinit/__devexit purge since they didn't match the pattern.
Remove then now to be rid of it.

v2: purge __init also

Reported-by: Arnd Bergmann <arnd@arndb.de>
[Arnd set a patch cleaning up one, and then I found more]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/s3c64xx: fix checkpatch warnings and error

Fix checkpatch warnings and error as below:
ERROR: "foo * bar" should be "foo *bar"
WARNING: please, no space before tabs
WARNING: quoted string split across lines
WARNING: msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.txt

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/s3c64xx: Use devm_clk_get() and devm_request_irq()

Use devm_clk_get() and devm_request_irq() rather than clk_get() and
request_irq() to make cleanup paths more simple.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: remove check for bits_per_word on transfer from low level driver

The spi core make sure that each transfer structure have the proper
setting for bits_per_word before calling low level transfer APIs.

Hence it is no more require to check again in low level driver for
this field whether this is set correct or not. Removing such code
from low level driver.

The txx9 change also removes a test for bits_per_word set to 0, and
forcing it to 8 in that case. This can also be removed now since
spi_setup() ensures spi->bits_per_word is not zero.

if (!spi->bits_per_word)
spi->bits_per_word = 8;

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: s3c64xx: Modify SPI driver to use generic DMA DT support

This patch modifies the SPI driver to use generic dma dt bindings
support. This passes all the required arguments to dma dev request
functon which in turn calls the dma_request_slave_channel or dma__
request_channel based on DT or non-DT respectively.

Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: Convert to devm_ioremap_resource()

Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

devm_ioremap_resource() provides its own error messages so all explicit
error messages can be removed from the failure code paths.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spi/s3c64xx: Complain if we fail to set a transfer speed

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: Change FIFO flush operation and spi channel off

Setting SW_RST does TX/RX FIFO flush.
After FIFO flush, SW_RST should be cleared.
The above setting and clearing SW_RST operation should be done after spi channel off.

Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: Keep chipselect assertion during one message

During all transfers in one message, the device will not be chagned.
So we don't need to deassert chipselect during one message.

Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

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: s3c64xx: Add fix for crash in spi suspend/resume

The SPI driver makes a gpio_request during initialization. The requested
gpios need to be populated as part of the s3c64xx_spi_driver_data so that
they can be released during suspend and requested again during resume.

Add the missing code to save the requested gpios as part of the driver
data. This fixes a SPI driver suspend crash.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/s3c64xx: use correct dma_transfer_direction type

There is a subtle difference between dma_transfer_direction and
dma_data_direction: the former is used by the dmaengine framework,
while the latter is used by the dma-mapping API. Although the
purpose is comparable, the actual values are different and must
not be mixed. In this case, the driver just wants to use
dma_transfer_direction.

Without this patch, building s3c6400_defconfig results in:

drivers/spi/spi-s3c64xx.c: In function 's3c64xx_spi_dmacb':
drivers/spi/spi-s3c64xx.c:239:21: warning: comparison between
'enum dma_data_direction' and 'enum dma_transfer_direction' [-Wenum-compare]

As pointed out by Kukjin Kim, this also changes the use of constants
from DMA_FROM_DEVICE/DMA_TO_DEVICE to DMA_DEV_TO_MEM/DMA_MEM_TO_DEV.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: spi-devel-general@lists.sourceforge.net

spi/s3c64xx: use clk_prepare_enable and clk_disable_unprepare

Convert clk_enable/clk_disable to clk_prepare_enable/clk_disable_unprepare
calls as required by common clock framework.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

dt/s3c64xx/spi: Use of_get_child_by_name to get a named child

As follow-up to "dt: introduce of_get_child_by_name to get child node by
name." patch, This patch removes some of the code duplication in the
driver by replacing it with of_get_child_by_name instead.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>

spi/s3c64xx: Don't free controller_data on non-dt platforms

When s3c64xx-spi is instantiated from device tree an instance of
struct s3c64xx_spi_csinfo is dynamically allocated in the driver.
For non-dt platform it is passed from board code through
spi_register_board_info(). On error path in s3c64xx_spi_setup()
function there is an attempt to free this data struct
s3c64xx_spi_csinfo object as it would have been allocated in the
driver for both, dt and non-dt based platforms. This leads to
following bug when gpio request fails:

spi spi1.0: Failed to get /CS gpio [21]: -16
kernel BUG at mm/slub.c:3478!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 Not tainted (3.6.0-rc5-00092-g9b0b493-dirty #6111)
PC is at kfree+0x148/0x158
LR is at s3c64xx_spi_setup+0xac/0x290
pc : [<c00a513c>] lr : [<c0227014>] psr: 40000013
sp : ee043e10 ip : c032883c fp : c0481f7c
r10: ee0abd80 r9 : 00000063 r8 : 00000000
r7 : ee129e78 r6 : ee104a00 r5 : fffffff0 r4 : c047bc64
r3 : 40000400 r2 : c047bc64 r1 : c04def60 r0 : 0004047b
Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 10c5387d Table: 4000404a DAC: 00000015
Process swapper/0 (pid: 1, stack limit = 0xee0422f0)
Stack: (0xee043e10 to 0xee044000)
...
[<c00a513c>] (kfree+0x148/0x158) from [<c0227014>] (s3c64xx_spi_setup+0xac/0x290)
[<c0227014>] (s3c64xx_spi_setup+0xac/0x290) from [<c02251a4>] (spi_setup+0x34/0x4c)
[<c02251a4>] (spi_setup+0x34/0x4c) from [<c02258d0>] (spi_add_device+0x98/0x128)
[<c02258d0>] (spi_add_device+0x98/0x128) from [<c02259d4>] (spi_new_device+0x74/0xa8)
[<c02259d4>] (spi_new_device+0x74/0xa8) from [<c0225a2c>] (spi_match_master_to_boardinfo+0x24/0x44)
[<c0225a2c>] (spi_match_master_to_boardinfo+0x24/0x44) from [<c0225b40>] (spi_register_master+0xf4/0x2a8)
[<c0225b40>] (spi_register_master+0xf4/0x2a8) from [<c043fe0c>] (s3c64xx_spi_probe+0x34c/0x42c)
[<c043fe0c>] (s3c64xx_spi_probe+0x34c/0x42c) from [<c01fc198>] (platform_drv_probe+0x18/0x1c)

There should be no attempt to kfree controller_data when it was
externally provided through the board code. Fix this by freeing
controller_data only when dev->of_node is not null.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

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

spi/s3c64xx: Drop extra calls to spi_master_get in suspend/remove functions

Suspend and resume functions call spi_master_get() without matching
spi_master_put(). The extra references are unnecessary and cause subsequent
module unload attempts to fail. Drop the calls.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/s3c64xx: improve error handling

When a device tree definition os an s3c64xx SPI master is missing
a "controller-data" subnode, the newly added s3c64xx_get_slave_ctrldata
function might use uninitialized memory in place of that node,
which was correctly reported by gcc.

Without this patch, building s3c6400_defconfig results in:

drivers/spi/spi-s3c64xx.c: In function 's3c64xx_get_slave_ctrldata.isra.25':
drivers/spi/spi-s3c64xx.c:841:5: warning: 'data_np' may be used uninitialized in this function [-Wuninitialized]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Jaswinder Singh <jaswinder.singh@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>

spi/s3c64xx: Add missing static storage class specifiers

Silences the following sparse warnings:
drivers/spi/spi-s3c64xx.c:1482:32: warning:
symbol 's3c2443_spi_port_config' was not declared. Should it be static?
drivers/spi/spi-s3c64xx.c:1489:32: warning:
symbol 's3c6410_spi_port_config' was not declared. Should it be static?
drivers/spi/spi-s3c64xx.c:1495:32: warning:
symbol 's5p64x0_spi_port_config' was not declared. Should it be static?
drivers/spi/spi-s3c64xx.c:1501:32: warning:
symbol 's5pc100_spi_port_config' was not declared. Should it be static?
drivers/spi/spi-s3c64xx.c:1508:32: warning:
symbol 's5pv210_spi_port_config' was not declared. Should it be static?
drivers/spi/spi-s3c64xx.c:1515:32: warning:
symbol 'exynos4_spi_port_config' was not declared. Should it be static?

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

spi/s3c64xx: Expand S3C64XX_SPI_{DE,}ACT macros at call sites

They have very few users and they're both just doing a single register
write so the advantage of having the macro is a bit limited. An inline
function might make sense but it's as easy to just do the writes directly.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi/s3c64xx: Convert to devm_request_and_ioremap()

Saves some error handling and a small amount of code.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi/s3c64xx: Put the /CS GPIO into output mode

No call was being made by the GPIO driver to put the GPIO into output
mode meaning that the calls to gpio_set_value() which were being done
were not valid. A similar issue appears to exist with the DT GPIO
requests but as they appear to be being used for pinmux it's less clear
to me that we want to configure them.

Without this fix Cragganmore systems can't talk to their SPI devices.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi/s3c64xx: Fix handling of errors in gpio_request()

When gpio_request() fails the driver logged the failure but while it'd
try to print an error code in the non-DT case it didn't pass the error
code in so garbage would be logged and in the DT case the error wasn't
logged.

Further, in the non-DT case the error code was then overwritten with -EBUSY
depriving the caller of information and breaking automatic probe deferral
pushing back from the GPIO level. Also reformat the non-DT log message
so it's not word wrapped and we can grep for it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: add device tree support

Add support for device based discovery.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Jaswinder Singh <jaswinder.singh@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: Remove the 'set_level' callback from controller data

The set_level callback in the controller data, which is used to configure
the slave select line, cannot be supported when migrating the driver to
device tree based discovery. Since all the platforms currently use gpio
as the slave select line, this callback can be removed from the
controller data and replaced with call to gpio_set_value in the driver.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Jaswinder Singh <jaswinder.singh@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

ARM: SAMSUNG: Remove pdev pointer parameter from spi gpio setup functions

The platform data pointer that is passed to the spi gpio setup functions
is not used. Hence, this parameter is removed from all the spi gpio setup
functions.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Jaswinder Singh <jaswinder.singh@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: move controller information into driver data

Platform data is used to specify controller hardware specific information
such as the tx/rx fifo level mask and bit offset of rx fifo level. Such
information is not suitable to be supplied from device tree. Instead,
it can be moved into the driver data and removed from platform data.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Jaswinder Singh <jaswinder.singh@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: remove unused S3C64XX_SPI_ST_TRLCNTZ macro

The macro S3C64XX_SPI_ST_TRLCNTZ is not used and hence it is removed.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Jaswinder Singh <jaswinder.singh@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi/s3c64xx: Add the use of DMA config operation

Config operation is separated from request operation in
DMA common operation. Because spi driver can change the
DMA config for every transfer. So this patch is using the
separated DMA config operation.

Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi: s3c64xx: Fix build

Commit 054ebc (spi: Compatibility with direction which is used in samsung
DMA operation) does not build as one hunk adds a brace to the first branch
of an if statement without adding at least the correspoding close. Remove
the unwanted brace.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: s3c64xx: remove unnecessary callback msg->complete

msg->complete will be called in spi_finalize_current_message().

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: Compatibility with direction which is used in samsung DMA operation

I found that there are two kind of direction type.
First one is dma_data_direction defined in include/linux/dma-direction.h.
It is used for parameter of dma_map/unmap_single in spi-s3c64xx.
The other one is dma_transter_direction defined in include/linux/dmaengine.h.
It is used for direction of samsung DMA operation
(arch/arm/plat-samsung/dma-ops.c).
This patch is just some changes to use direction defines
which is used in samsung DMA operation.

Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/s3c64xx: Convert to using core message queue

Convert the s3c64xx driver to using the new message queue factored out of
the pl022 driver by Linus Walleij, saving us a nice block of code and
getting the benefits of improvements implemented in the core.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/s3c64xx: Implement runtime PM support

Enable and disable the clocks to the SPI controller using runtime PM. This
serves the dual purpose of reducing power consumption a little and letting
the core know when the device is idle.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>

spi/s3c64xx: Convert to dev_pm_ops

In preparation for the addition of runtime PM ops.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/s3c64xx: Log error interrupts

Although the hardware supports interrupts we're not currently using them
at all since for small transfers the overhead is greater than that for
busy waiting and for large transfers we have interrupts from the DMA.
This means that if the hardware reports an error (especially one which
might not stall transfer) we might miss it.

Take a first pass at dealing with such errors by enabling the interrupt
if we can and logging the errors if they happen. Ideally we'd report the
error via the affected transfer but since we're in master mode it's very
difficult to trigger errors at present and this code is much simpler.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>

spi/s3c64xx: Use bus clocks created using clkdev

This patch modifies the driver to stop depending on the
clock names being passed from platform and switch over
to lookup clocks generic names using clkdev

Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

spi/s3c64xx: Merge dma control code

This patch modifies to merge the dma control code. Original
s3c64xx spi driver has each dma control code for rx and tx
channel. This patch merges these dma control codes into one.
With this patch, a dma setup function and callback function
handle for both rx and tx channel.

Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

spi/s3c64xx: Add support DMA engine API

This patch adds to support DMA generic API to transfer raw
SPI data. Basiclly the spi driver uses DMA generic API if
architecture supports it. Otherwise, uses Samsung specific
S3C-PL330 APIs.

Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

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>