Commit Graph

191 Commits

Author SHA1 Message Date
Colin Ian King
9723070ecb
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>
2022-06-08 11:49:34 +01:00
Adithya K V
f52b03c707
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>
2022-06-06 12:39:17 +01:00
Mark Brown
87fee8d091
spi: Tesla FSD support
Merge series from Alim Akhtar:

This series adds support for the SPI controller in the Tesla FSD SoC,
also pulling in:

   git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git ib-mfd-spi-dt-v5.18

from the MFD tree which has dependencies for the DT bindings.
2022-03-08 20:07:09 +00:00
Alim Akhtar
4ebb15a157
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>
2022-03-08 17:25:38 +00:00
Krzysztof Kozlowski
7db7a24657 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
2022-03-07 12:55:36 +00:00
Linus Walleij
a45cf3cc72
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>
2022-01-24 13:37:33 +00:00
Krzysztof Kozlowski
d637141551
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>
2021-04-15 16:07:58 +01:00
Krzysztof Kozlowski
7d712f799a
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>
2021-04-15 16:07:57 +01:00
Krzysztof Kozlowski
609a2f9529
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>
2021-04-15 16:07:56 +01:00
Łukasz Stelmach
3f32131fbb
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>
2020-10-02 21:54:24 +01:00
Łukasz Stelmach
9fe26adbe3
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>
2020-10-02 21:54:23 +01:00
Łukasz Stelmach
20b4016a3b
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>
2020-10-02 21:54:22 +01:00
Łukasz Stelmach
58d5478143
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>
2020-10-02 21:54:21 +01:00
Łukasz Stelmach
913ba5c9e2
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>
2020-10-02 21:54:20 +01:00
Łukasz Stelmach
df7cd1bba2
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>
2020-10-02 21:54:19 +01:00
Łukasz Stelmach
2f4db6f705
spi: spi-s3c64xx: Check return values
Check return values in prepare_dma() and s3c64xx_spi_config() and
propagate errors upwards.

Fixes: 788437273f ("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>
2020-10-02 21:54:18 +01:00
Łukasz Stelmach
ab4efca29f
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>
2020-10-02 21:54:17 +01:00
Łukasz Stelmach
581e2b4197
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>
2020-10-02 21:54:16 +01:00
Lee Jones
6b8d1e4739
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>
2020-07-17 16:38:49 +01:00
Peter Ujfalusi
df1b014178
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>
2019-11-15 12:14:39 +00:00
Marek Szyprowski
e935dba111
spi: spi-s3c64xx: Fix system resume support
Since Linux v4.10 release (commit 1d9174fbc5 "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
2018-05-17 13:27:08 +09:00
Krzysztof Kozlowski
b6a4b39152
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>
2018-04-25 13:52:02 +01:00
Sylwester Nawrocki
0af7af7da6
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>
2018-04-18 12:37:33 +01:00
Sylwester Nawrocki
f6364e66c6
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>
2018-04-18 12:37:29 +01:00
Sylwester Nawrocki
3655d30c05
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>
2018-04-18 11:40:53 +01:00
Sylwester Nawrocki
80aa0d746c
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>
2018-04-18 11:40:49 +01:00
Sylwester Nawrocki
bfbd0ea85d
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>
2018-04-17 11:46:52 +01:00
Sylwester Nawrocki
4e0b82ee31
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>
2018-04-17 11:46:52 +01:00
Sylwester Nawrocki
1c75862d8e
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>
2018-04-17 11:46:52 +01:00
Sylwester Nawrocki
ee9b62d319
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>
2018-04-17 11:46:52 +01:00
Andi Shyti
78b5d705b5
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>
2018-01-08 15:38:06 +00:00
Colin Ian King
4132b8b910
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>
2017-11-03 17:21:10 +00:00
Mark Brown
e2a3b0df8d Merge remote-tracking branches 'spi/topic/rockchip', 'spi/topic/rspi', 'spi/topic/s3c64xx', 'spi/topic/sh-msiof' and 'spi/topic/slave' into spi-next 2017-02-19 16:41:05 +00:00
Andi Shyti
379f831a92 spi: s3c64xx: fix inconsistency between binding and driver
Commit a92e7c3d82 ("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: a92e7c3d82 ("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
2017-02-13 18:47:38 +00:00
Dan Carpenter
72bc7ae063 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: 3d63a47a38 ("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>
2017-01-17 17:58:51 +00:00
Marek Szyprowski
3d63a47a38 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>
2017-01-09 12:21:04 +00:00
Sylwester Nawrocki
6f8dc9d481 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>
2016-11-17 15:51:28 +05:30
Andi Shyti
0dbe70a1fe 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>
2016-07-14 17:28:32 +01:00
Andi Shyti
7990b00819 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>
2016-07-14 17:28:32 +01:00
Andi Shyti
25981d8281 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>
2016-07-14 17:28:31 +01:00
Andi Shyti
60a9a96442 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>
2016-07-14 17:28:31 +01:00
Wei Yongjun
9f135787b1 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>
2016-07-14 17:21:52 +01:00
Andi Shyti
d9aaf1dc98 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>
2016-07-07 11:24:32 +02:00
Dan Carpenter
47c169ee67 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>
2016-07-04 10:47:58 +02:00
Andi Shyti
730d9d4d11 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>
2016-06-29 22:45:23 +01:00
Andi Shyti
11f66f0927 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>
2016-06-29 22:45:23 +01:00
Andi Shyti
a92e7c3d82 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>
2016-06-29 22:45:23 +01:00
Andi Shyti
aa4964c4eb 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>
2016-06-29 22:45:15 +01:00
Sylwester Nawrocki
cc023478dc 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>
2015-12-30 16:48:58 +00:00
Arnd Bergmann
a0067db36a 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>
2015-11-18 17:52:38 +00:00