The MCSPI controller has a built-in FIFO buffer to unload the DMA or interrupt
handler and improve data throughput. This patch adds FIFO buffer support for SPI
transfers in DMA mode.

For SPI transfers in DMA mode, the largest possible FIFO buffer size will be
calculated and set up. The FIFO won't be used for the SPI transfers in DMA mode
if: calculated FIFO buffer size is less then 2 bytes or the FIFO buffer size
isn't multiple of the SPI word length.
Signed-off-by: NIllia Smyrnov <illia.smyrnov@ti.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Introduce mcspi_bytes_per_word function as replacement for the next code
fragment:

int c = (word_len <= 8)  ? 1 :
	(word_len <= 16) ? 2 :
	/* word_len <= 32 */ 4;

This code used 2 times in current driver code and will be used 2 times in
the next FIFO buffer support patch. Replace it with inline function with clear
name to improve code legibility.
Signed-off-by: NIllia Smyrnov <illia.smyrnov@ti.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Since commit ab78029e (drivers/pinctrl: grab default handles from device
core) we can rely on device core for handling pinctrl so remove
devm_pinctrl_get_select_default() from the driver.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Fix to return a negative error code from the error handling
case instead of 0, as returned elsewhere in this function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Selecting CONFIG_DMADEVICES is optional, and we must
be able to continue even without DMA. Otherwise things
like omap4430sdp nfsroot will fail if DMA is not
selected.

Note that the driver already supports PIO mode, but
we fail to fall back to PIO if requesting DMA channels
fails.
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NMark 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: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

No actual errors have been found for completing
before disabling DMA request lines, but it just
looks more semantically correct that on our DMA
callback we quiesce the whole thing before stating
transfer is finished.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

This patch allows the board code to define SPI devices which needs to
toggle the chip select after every word send. This is needed to get a
better resolution reading e.g. an ADC data stream.
Apart from that, as in the normal code CS is controlled by software,
a transfer is done much faster.
Signed-off-by: NMatthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

This patch fixes some indentation errors.
Signed-off-by: NMatthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: NJarkko Nikula <jarkko.nikula@bitmer.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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

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: NBill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

linux/err.h was included twice.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Fix the below warning
drivers/spi/spi-omap2-mcspi.c:336:34: warning: symbol 'tx' shadows an earlier one
drivers/spi/spi-omap2-mcspi.c:327:12: originally declared here

So delete the u8 tx as it is assigned and not used(resigned afterwards).
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NPeter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Remove duplicated include.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

0384e90b ("spi/mcspi: allow configuration of pin directions") did what
it claimed to do the wrong way around. D0/D1 is configured as output by
*clearing* the bits in the conf registers, hence also breaking the
former default behaviour.

Fix this before that change is merged to mainline.
Signed-off-by: NDaniel Mack <zonque@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The commit  d7b4394e[Cleanup the omap2_mcspi_txrx_dma function]
changed the wait_for_completion order. Move the wait so that the
rx doesnot wait for the tx to complete.
Reported-and-tested-by: NSørensen, Stefan <Sorensen@polycom.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Allow D0 to be an input and D1 to be an output, configurable via
platform data and a new DT property.

Based on a patch from  Matus Ujhelyi <matus.ujhelyi@streamunlimited.com>
Signed-off-by: NDaniel Mack <zonque@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Remove unnecessary includes of plat/clock.h from the OMAP SPI
controller drivers.  These need to be removed to build multi-subarch
ARM kernels which include these drivers.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>

Adds pinctrl support to support OMAP platforms that boot from DT
and rely on pinctrl support to set pinmuxes.
Signed-off-by: NMatt Porter <mporter@ti.com>
Acked-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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 omap include directories
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NTony Lindgren <tony@atomide.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: "Benoît Cousson" <b-cousson@ti.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Omar Ramirez Luna <omar.ramirez@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: Jarkko Nikula <jarkko.nikula@bitmer.com>
Cc: Liam Girdwood <lrg@ti.com>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Jean Pihet <j-pihet@ti.com>
Cc: J Keerthy <j-keerthy@ti.com>
Cc: linux-omap@vger.kernel.org

Currently in omap2_mcspi_txrx_dma the tx and the rx support is
interleaved. Make the rx related code in omap2_mcspi_rx_dma
and the tx related code omap2_mcspi_tx_dma and call the functions.

While at it remove the braces in the if statements which has only
one line.
Also fix ["foo * bar" to "foo *bar"] warn for the rx and tx variables.

Only a cleanup no functional change.
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Tested-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

At remove we shouldnt be using the autosuspend timeout as we are
calling pm_runtime_disable immediately after.
Acked-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Call the pm_runtime functions directly making room for possible
pm optimisations. Also the runtime functions aren't just about
enabling and disabling of clocks though it does enable clocks also.
Acked-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Remove the macro MOD_REG_BIT instead make the bit field modifications
directly. This deletes a branch operation in cases where the the set
is predecided. While at it optimise two sequential bit clear in one step.
Acked-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Remove the call of platform_set_drvdata(pdev, NULL) as they are not
needed anymore.
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The kfree() is taken care of by the spi core (spi_master_release() function)
that is called once the last reference to the underlying struct device has
been released. So the driver need not call kfree.

Also the put was missed in some of the error handling fix the same.
There by fixing the missing device_put in some of the error paths.
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

This prepares *of_device_id.data becoming const. Without this change
the following warning would occur:

	drivers/spi/spi-omap2-mcspi.c: In function 'omap2_mcspi_probe':
	drivers/spi/spi-omap2-mcspi.c:1118: warning: assignment discards qualifiers from pointer target type
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>

Remove the private DMA API implementation from spi-omap2-mcspi.c,
making it use entirely the DMA engine API.
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add DMA engine support to the OMAP SPI driver.  This supplements the
private DMA API implementation contained within this driver, and the
driver can be independently switched at build time between using DMA
engine and the private DMA API for the transmit and receive sides.
Tested-by: NShubhrajyoti <shubhrajyoti@ti.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This warning recently appeared with omap2plus_defconfig:

WARNING: drivers/spi/built-in.o(.devinit.text+0x3c4): Section mismatch in reference from the function omap2_mcspi_probe() to the function .init.text:omap2_mcspi_master_setup()
The function __devinit omap2_mcspi_probe() references
a function __init omap2_mcspi_master_setup().
If omap2_mcspi_master_setup is only used by omap2_mcspi_probe then
annotate omap2_mcspi_master_setup with a matching annotation.

The fix is obviously to mark the omap2_mcspi_master_setup function as
__devinit, rather than __init.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The dma_map and dma_unmap should have same parameter
passed otherwise we get the below warn.

ks8851 spi1.0: DMA-API: device driver tries to free DMA memory it has not allocated [device address=0x000000009f22]

[    2.066925] Modules linked in:
[    2.070312]
[    2.071929] [<c001c250>] (unwind_backtrace+0x0/0x130) from [<c0043d84>] (warn_slowpath_common+0x4c/0x64)
[    2.081909] [<c0043d84>] (warn_slowpath_common+0x4c/0x64) from [<c0043e30>] (warn_slowpath_fmt+0x30/0x40)
[    2.091949] [<c0043e30>] (warn_slowpath_fmt+0x30/0x40) from [<c0293824>] (check_unmap+0x6d0/0x7b0)
[    2.101348] [<c0293824>] (check_unmap+0x6d0/0x7b0) from [<c02939cc>] (debug_dma_unmap_page+0x64/0x70)
[    2.111053] [<c02939cc>] (debug_dma_unmap_page+0x64/0x70) from [<c03519a4>] (omap2_mcspi_txrx_dma+0x2d8/0x4fc)
[    2.121582] [<c03519a4>] (omap2_mcspi_txrx_dma+0x2d8/0x4fc) from [<c03524d8>] (omap2_mcspi_work.clone.4+0xf0/0x290)
[    2.132537] [<c03524d8>] (omap2_mcspi_work.clone.4+0xf0/0x290) from [<c0352900>] (omap2_mcspi_transfer_one_message+0x288/0x438)
[    2.144592] [<c0352900>] (omap2_mcspi_transfer_one_message+0x288/0x438) from [<c03503bc>] (spi_pump_messages+0x100/0x160)
[    2.156127] [<c03503bc>] (spi_pump_messages+0x100/0x160) from [<c006635c>] (kthread_worker_fn+0xac/0x180)
[    2.166168] [<c006635c>] (kthread_worker_fn+0xac/0x180) from [<c0066578>] (kthread+0x90/0x9c)
[    2.175140] [<c0066578>] (kthread+0x90/0x9c) from [<c00157fc>] (kernel_thread_exit+0x0/0x8)
[    2.183898] ---[ end trace d1830ce6e44292f2 ]---

Fix the warn by changing the unmap parameter.
Reported-by: NRussell King - ARM Linux <linux@arm.linux.org.uk>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

1a77b127 (OMAP : SPI : use devm_* functions) converted the SPI
device controller state to use devm_kzalloc().  Unfortunately, this
is used against an unbound struct device, which results in the
following when the device is bound to its driver:

------------[ cut here ]------------
WARNING: at /home/rmk/git/linux-rmk/drivers/base/dd.c:257 driver_probe_device+0x78/0x21c()
Modules linked in:
Backtrace:
[<c0017d0c>] (dump_backtrace+0x0/0x10c) from [<c033e208>] (dump_stack+0x18/0x1c) r7:00000000 r6:c01ff28c r5:c040050c r4:00000101
[<c033e1f0>] (dump_stack+0x0/0x1c) from [<c00337ec>] (warn_slowpath_common+0x58/0x70)
[<c0033794>] (warn_slowpath_common+0x0/0x70) from [<c0033828>] (warn_slowpath_null+0x24/0x2c)
[<c0033804>] (warn_slowpath_null+0x0/0x2c) from [<c01ff28c>] (driver_probe_device+0x78/0x21c)
[<c01ff214>] (driver_probe_device+0x0/0x21c) from [<c01ff49c>] (__driver_attach+0x6c/0x90)
[<c01ff430>] (__driver_attach+0x0/0x90) from [<c01fda70>] (bus_for_each_dev+0x58/0x98)
[<c01fda18>] (bus_for_each_dev+0x0/0x98) from [<c01ff0f4>] (driver_attach+0x20/0x28)
[<c01ff0d4>] (driver_attach+0x0/0x28) from [<c01fe2f4>] (bus_add_driver+0xb4/0x230)
[<c01fe240>] (bus_add_driver+0x0/0x230) from [<c01ffb24>] (driver_register+0xac/0x138)
[<c01ffa78>] (driver_register+0x0/0x138) from [<c0215d4c>] (spi_register_driver+0x4c/0x60)
[<c0215d00>] (spi_register_driver+0x0/0x60) from [<c045414c>] (ks8851_init+0x14/0x1c)
[<c0454138>] (ks8851_init+0x0/0x1c) from [<c0008770>] (do_one_initcall+0x9c/0x164)
[<c00086d4>] (do_one_initcall+0x0/0x164) from [<c0436410>] (kernel_init+0x128/0x210)
[<c04362e8>] (kernel_init+0x0/0x210) from [<c0038754>] (do_exit+0x0/0x72c)
---[ end trace 4dcda79f5e89dd84 ]---
ks8851 spi1.0: message enable is 0
ks8851 spi1.0: eth0: revision 0, MAC 08:00:28:01:4d:c6, IRQ 194, has EEPROM

Fix this by partially reverting the original commit.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch converts the OMAP SPI driver to use the SPI infrastructure
pump message queue.Also fixes the below warning.
master is unqueued, this is deprecated
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Trivial optimisation of tmp variable by directly writing the value
to the register.

Cc: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>

Adds support for configuring the omap2-mcspi driver use autosuspend for
runtime power management. This can reduce the latency in starting an
spi transfer by not suspending the device immediately following
completion of a transfer. If another transfer then takes place before
the autosuspend timeout (2 secs), the call to resume the device can
return immediately saving some save/ restore cycles.
Acked-by: NGovindraj.R <govindraj.raja@ti.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>

bus_num was used to reference the mcspi controller instance in a fixed array.
Remove this array and store this information directly inside drvdata structure.

bus_num is now just set if the pdev->id is present or with -1 for dynamic
allocation by SPI core, but the driver does not access it anymore.

Clean some bad comments format, and remove un-needed space.
Signed-off-by: NBenoit Cousson <b-cousson@ti.com>
[Cleanup the OMAP2_MCSPI_MAX_CTRL macro as it is not needed anymore]
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>

The various devm_* functions allocate memory that is released when a driver
detaches. This patch uses devm_request_and_ioremap
to request memory in probe function. Since the freeing is not
needed the calls are deleted from remove function.Also use
use devm_kzalloc for the cs memory allocation.
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>

this will delete a few lines of code, no functional
changes.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>

move probe away from __init section and use
platform_driver_register() instead of
platform_driver_probe().
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NShubhrajyoti D <shubhrajyoti@ti.com>

Add device tree support to the OMAP2+ McSPI driver.
Add the bindings documentation.

Based on original code from Rajendra.
Signed-off-by: NBenoit Cousson <b-cousson@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>