This patch relies on the CSAAT (Chip Select Active After Transfer) feature
introduced by the version 2 of the spi controller. This new mode allows to
use properly the internal chip-select output pin of the spi controller
instead of using external gpios. Consequently, the "cs-gpios" device-tree
property becomes optional.

When the new CSAAT bit is set into the Chip Select Register, the internal
chip-select output pin remains asserted till both the following conditions
become true:
- the LASTXFER bit is set into the Control Register (or the Transmit Data
  Register)
- the Transmit Data Register and its shift register are empty.

WARNING: if the LASTXFER bit is set into the Control Register then new
data are written into the Transmit Data Register fast enough to keep its
shifter not empty, the chip-select output pin remains asserted. Only when
the shifter becomes empty, the chip-select output pin is unasserted.

When the CSAAT bit is clear in the Chip Select Register, the LASTXFER bit
is ignored in both the Control Register and the Transmit Data Register.
The internal chip-select output pin remains active as long as the Transmit
Data Register or its shift register are not empty.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Use the endian agnositc IO functions instead of the __raw ones for when
the driver is in use on big-endian systems.
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Additionally to the current DMA transfer the PDC allows to set up a next DMA
transfer. This is useful for larger SPI transfers.

The driver currently waits for ENDRX as end of the transfer. But ENDRX is set
when the current DMA transfer is done (RCR = 0), i.e. it doesn't include the
next DMA transfer.
Thus a subsequent SPI transfer could be started although there is currently a
transfer in progress. This can cause invalid accesses to the SPI slave devices
and to SPI transfer errors.

This issue has been observed on a hardware with a M25P128 SPI NOR flash.

So instead of ENDRX we should wait for RXBUFF. This flag is set if there is
no more DMA transfer in progress (RCR = RNCR = 0).
Signed-off-by: NTorsten Fleischer <torfl6749@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

return type of wait_for_completion_timeout is unsigned long not int, this
patch adds an appropriate variable and fixes up the assignment. It removes
the else branch as the only thing it was doing is assigning ret = 0; - but
ret is never used thereafter so that is not needed. As the string in
dev_err already states "timeout" there is little point in printing the 0.
A typo in "trasfer" -> transfer is also fixed.
Signed-off-by: NNicholas Mc Guire <hofrat@osadl.org>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Return probe defer if requesting a dma channel without a dma controller
probed.
Signed-off-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

All boards with a dma controller have DT support so using
dma_request_slave_channel_compat is no more needed.
Signed-off-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

To make it cleaner, the system suspend/resume directly call
the runtime suspend/resume functions
and remove the wapper of CONFIG_PM_RUNTIME, CONFIG_PM_SLEEP.
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Acked-by: NKevin Hilman <khilman@linaro.org>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

A platform_driver does not need to set an owner, it will be populated by the
driver core.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

drivers/spi/spi-atmel.c:1518:1-4: WARNING: end returns can be simpified and declaration on line 1514 can be dropped

 Simplify a trivial if-return sequence.  Possibly combine with a
 preceding function call.
Generated by: scripts/coccinelle/misc/simple_return.cocci
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Drivers should put the device into low power states proactively whenever the
device is not in use. Thus implement support for runtime PM and use the
autosuspend feature to make sure that we can still perform well in case we see
lots of SPI traffic within short period of time.
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The drivers should use dmaengine_terminate_all() API instead of
accessing the device_control which will be deprecated soon
Signed-off-by: NVinod Koul <vinod.koul@intel.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

On 64 bit systems integers are generally still 32 bit but long values and
pointers are usually 64 bit. GCC warns when casting a 64 bit pointer into
a 32 bit integer so cast to a long instead in order to avoid warnings.
Signed-off-by: NMark Brown <broonie@linaro.org>

Use the inline wrapper introduced by commit
16052827 ("dmaengine/dma_slave: introduce
inline wrappers").
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Found using smatch:
drivers/spi/spi-atmel.c:878 atmel_spi_pump_pio_data() warn: unsigned
'as->current_remaining_bytes' is never less than zero.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

atmel_spi_lock does a spin_lock_irqsave, so we need to renable the
interrupts when we want to schedule.
Signed-off-by: NAlexander Stein <alexanders83@web.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

Don't use unsigned for current_remaining_bytes so we can check
current_remaining_bytes < 0 case.
Use int is enough for current_remaining_bytes.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Fix printk format warning by using %p extension 'ad' for dma_addr_t.

drivers/spi/spi-atmel.c:1228:3: warning: format '%x' expects argument of type 'unsigned int', but argument 7 has type 'dma_addr_t' [-Wformat]
drivers/spi/spi-atmel.c:1228:3: warning: format '%x' expects argument of type 'unsigned int', but argument 9 has type 'dma_addr_t' [-Wformat]
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

The PM callbacks implemented by the spi-atmel driver don't call
spi_master_{resume,suspend}, fix that.
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Amend the spi atmel pin controller to optionally take a pin control
handle and set the state of the pins to:

- "default" on boot, resume and before performing an spitransfer
- "sleep" on suspend()

This should make it possible to optimize energy usage for the pins
both for the suspend/resume cycle
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

spi core will handle validating transfer length since commit 4d94bd21
"spi: core: Validate length of the transfers in message".
So remove the same checking in this driver.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

This checking is already done in __spi_validate().
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

In spi_add_device(), we have the code to validate spi->chip_select.
So remove the duplicate code in various drivers.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Replace the deprecated master->transfer with transfer_one_message()
and allow the SPI subsystem handle all the queuing of messages.
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Tested-by: NRichard Genoud <richard.genoud@gmail.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

The only speed available was max_speed (the maximum speed declared for a
device).
This patch adds the support for spi_tranfer->speed_hz parameter.
We can now set a different speed for each spi message.
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Use devm_*() functions to make cleanup paths simpler.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should be
replaced with IS_ERR().
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

This simplifies error handling.
Signed-off-by: NMark Brown <broonie@linaro.org>

User-visible strings are more difficult to grep from sources if they are
separated to multiple source lines. This is worse than over 80 columns long
line code style violation.

Fix this by making those to single-line strings or by breaking them between
variables.

While at there, convert if (printk_ratelimit()) dev_warn() to use
dev_warn_ratelimited in spi-pxa2xx.c.
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Fix the following checkpatch warning.

  WARNING: quoted string split across lines
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

'irq' was not released when clk_prepare_enable failed.
Fix it.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Fixes the following types of checkpatch errors and warning:
ERROR: space required after that ',' (ctx:VxV)
WARNING: sizeof *as should be sizeof(*as)
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Instead of using legacy suspend/resume methods, using newer
dev_pm_ops structure allows better control over power management.
Also, duplicated 'return' is removed from atmel_spi_resume().
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

'irq' was not released when clk_prepare_enable failed.
Fix it.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

This patch fixes the following sparse warnings.
dma_addr_t can be either u32 or u64 so we should cast to the
largest type and use the format specifier %llx.

drivers/spi/spi-atmel.c: In function ‘atmel_spi_next_xfer_dma_submit’:
drivers/spi/spi-atmel.c:631:2: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 7 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:631:2: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 9 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c: In function ‘atmel_spi_pdc_next_xfer’:
drivers/spi/spi-atmel.c:734:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 7 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:734:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 9 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:773:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 7 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:773:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 9 has type ‘dma_addr_t’ [-Wformat]
Signed-off-by: NEmil Goode <emilgoode@gmail.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Let checkers like sparse know that the locking imbalances are intentional
in these functions.
Signed-off-by: NMark Brown <broonie@linaro.org>

Replace clk_enable/disable with clk_prepare_enable/disable_unprepare to
avoid common clk framework warnings.
Signed-off-by: NBoris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Use generic DMA DT helper.
Platforms booting with or without DT populated are both supported.

Based on Ludovic Desroches <ludovic.desroches@atmel.com> patchset
"ARM: at91: move to generic DMA device tree binding"
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
Acked-by: NLudovic Desroches <ludovic.desroches@gmail.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

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: NStephen Warren <swarren@wwwdotorg.org>
Acked-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Fix using PIO transfer mode only support 8 bits transfer, doesn't support 16 bits.
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
[wenyou.yang@atmel.com: submit the patch]
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>