This reverts commit faa98f7e which was
applied in error due to discussion ending up in the wrong thread.

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>

The status of transfer is stored in controller data structure
so that it can be used not only by atmel_spi_msg_done() function.
This will be useful for upcoming dmaengine enabled driver.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The "has_dma_support" needed for future use with dmaengine driver.

[Fixed some unneded ternery operators -- broonie]
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Spi starts transfer using dma with DMA_CTRL_ACK which is not require
becasue spi driver does not use completed dma_desc after transfer
done and so it does not ack the dma descriptor. Removing the
DMA_CTRL_ACK flag to avoid memory leak in dma driver.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Replaced calls to IS_ERR and PTR_ERR with PTR_RET function.
Patch found using coccinelle.
Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Replaced calls to IS_ERR and PTR_ERR with PTR_RET function.
Patch found using coccinelle.
Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Some SPI slave devices require asserted chip select signal across
multiple transfer segments of an SPI message. Currently the driver
always de-asserts the internal SS signal for every single transfer
segment of the message and ignores the 'cs_change' flag of the
transfer description. Disable the internal chip select (SS) only
if this is needed and indicated by the 'cs_change' flag.

Without this change, each partial transfer of a surrounding
multi-part SPI transaction might erroneously change the SS
signal, which might prevent slaves from answering the request
that was sent in a previous transfer segment because the
transaction could be considered aborted (SS was de-asserted
before reading the response).
Reported-by: Gerhard Sittig <gerhard.sittig@ifm.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org

The variable bits_per_word is initialized but never used
otherwise, so remove the unused variable.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-By: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

This eliminates having an #ifdef returning NULL for the case
when OF is disabled.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

This eliminates having an #ifdef returning NULL for the case
when OF is disabled.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi_pump_messages() calls into a controller driver with
unprepare_transfer_hardware() which is documented as "This may sleep".
As in the prepare_transfer_hardware() call below, we should release the
queue_lock spinlock before making the call.
Rework the logic a bit to hold queue_lock to protect the 'busy' flag,
then release it to call unprepare_transfer_hardware().
Signed-off-by: Bryan Freed <bfreed@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

It is possible that the handler gets interrupted after checking the
status. After it resumes the time out is due but the condition it was
waiting for might be true as well. Therefore it is necessary to check
the condition in case of an time out to be sure that the condition is
not true after the time passed by.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The core can do the validation for us.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

This driver only supports bits_per_word==8, so inform the SPI core of
this. Remove all the open-coded validation that's no longer needed.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Allow SPI masters to define the set of bits_per_word values they support.
If they do this, then the SPI core will reject transfers that attempt to
use an unsupported bits_per_word value. This eliminates the need for each
SPI driver to implement this checking in most cases.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

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

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>

Use devm_ioremap_resource() which provides its own error messages.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

bcm63xx_spi_setup_transfer is called from only one place, and that has
t always set, to hz will always be t->speed_hz - just use it directly in
the two places instead of moving it in a local variable.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

It only does one check, so just do the check directly in the caller.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The check would belong in bcm63xx_spi_setup if the spi subsystem
weren't already doing the check for us, so just drop it.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

bcm63xx_spi_check_transfer is only called from one place that has
t always set, so directly check the transfer's bits_per_word.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Instead of fixing up the bits_per_word (which the spi subsystem already
does for us), check it for supported values.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

It is only written, but never read.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The spi subsystem already provides this info in a more extensive
debug print except for the nsecs/bit - which wasn't calculated anyway
and fixed to 0.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The spi subsystem already checks the mode bits before calling setup.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Use proper clk_prepare/unprepare calls in preparation for switching
to the generic clock framework.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

When msg_ctl_width is set to an invalid value we try to disable the
clock despite it never being enabled. Fix it by jumping to the correct
label.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

This fixes the following warning:

drivers/spi/spi-bcm63xx.c: In function 'bcm63xx_spi_setup':
drivers/spi/spi-bcm63xx.c:157:6: warning: unused variable 'ret'
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The prepare_transfer_hardware() is called in atomic context and
calling synchronous runtime pm calls can create scheduling deadlock.

Therefore, in place of calling runtime PM calls from prepare/unprepare
message transfer, calling this in transfer_one_message().
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Intel LPSS SPI controllers need to have bit 0 (disable_ssp_dma_finish) set
in SSP_REG in order to properly perform DMA transfers spanning over
multiple blocks.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The function returns 0 on success and negative errno in case of failure.
Fix this.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

The BCM2835 contains two forms of SPI master controller (one known
simply as SPI0, and the other known as the "Universal SPI Master", in
the auxilliary block) and one form of SPI slave controller. This patch
adds support for the SPI0 controller.

This driver is taken from Chris Boot's repository at
git://github.com/bootc/linux.git rpi-linear
as of commit 6de2905 "spi-bcm2708: fix printf with spurious %s".
In the first SPI-related commit there, Chris wrote:

Thanks to csoutreach / A Robinson for his driver which I used as an
inspiration. You can find his version here:
http://piface.openlx.org.uk/raspberry-pi-spi-kernel-driver-available-for

Changes made during upstreaming:
* Renamed bcm2708 to bcm2835 as per upstream naming for this SoC.
* Removed support for brcm,realtime property.
* Increased transfer timeout to 30 seconds.
* Return IRQ_NONE from the IRQ handler if no interrupt was handled.
* Disable TA (Transfer Active) and clear FIFOs on a transfer timeout.
* Wrote device tree binding documentation.
* Request unnamed clock rather than "sys_pclk"; the DT will provide the
  correct clock.
* Assume that tfr->speed_hz and tfr->bits_per_word are always set in
  bcm2835_spi_start_transfer(), bcm2835_spi_transfer_one(), so no need
  to check spi->speed_hz or tft->bits_per_word.
* Re-ordered probe() to remove the need for temporary variables.
* Call clk_disable_unprepare() rather than just clk_unprepare() on probe()
  failure.
* Don't use devm_request_irq(), to ensure that the IRQ doesn't fire after
  we've torn down the device, but not unhooked the IRQ.
* Moved probe()'s call to clk_prepare_enable() so we can be sure the clock
  is enabled if the IRQ handler fires immediately.
* Remove redundant checks from bcm2835_spi_check_transfer() and
  bcm2835_spi_setup().
* Re-ordered IRQ handler to check for RXR before DONE. Added comments to
  ISR.
* Removed empty prepare/unprepare implementations.
* Removed use of devinit/devexit.
* Added BCM2835_ prefix to defines.
Signed-off-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

In case of error, the function platform_device_register_full()
returns ERR_PTR() and never returns NULL. The NULL test in the
return value check should be replaced with IS_ERR().
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>