The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

They are used to decide if the controller can do DMA on a buffer
of a specific length and thus are needed before any transfer is attempted.

This fixes a memory leak where the SPI core uses the drivers can_dma()
callback to determine if a buffer needs to be mapped. As the watermark
levels aren't correct at that point the driver falsely claims to be able to
DMA the buffer when it fact it isn't.
After the transfer has been done the core uses the same callback to
determine if it needs to unmap the buffers. As the driver now correctly
claims to not being able to DMA the buffer the core doesn't attempt to
unmap the buffer which leaves the SGT leaking.

Fixes: f62caccd (spi: spi-imx: add DMA support)
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

The fourth argument of dmaengine_prep_slave_sg needs to be of the
enumeration type dma_transfer_direction instead of dma_data_direction.
Since the used enumeration values actually stay the same, this is not
an actual issue at runtime.
Signed-off-by: NStefan Agner <stefan@agner.ch>
Signed-off-by: NMark Brown <broonie@kernel.org>

return type of wait_for_completion_timeout is unsigned long not int and
always returns >=0 , this patch adds a suitable return variable and
simplifies the return value checking as there is no < 0 case.
Signed-off-by: NNicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

For TKT238285 hardware issue which may cause txfifo store data twice can only
be caught on i.mx6dl, we use pio mode instead of DMA mode on i.mx6dl.

Fixes: f62caccd (spi: spi-imx: add DMA support)
Signed-off-by: NRobin Gong <b38343@freescale.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

The irq number is only used inside the probe function, so there is really no
need to store it in the private structure.

Use a local 'irq' variable to hold the the irq number instead.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.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>

Enable DMA support on i.mx6. The read speed can increase from 600KB/s
to 1.2MB/s on i.mx6q. You can disable or enable dma function in dts.
If not set "dma-names" in dts, spi will use PIO mode. This patch only
validate on i.mx6, not i.mx5, but encourage ones to apply this patch
on i.mx5 since they share the same IP.

Note:
  Sometime, there is a weid data in rxfifo after one full tx/rx
transfer finish by DMA on i.mx6dl, so we disable dma functhion on
i.mx6dl.
Signed-off-by: NFrank Li <Frank.Li@freescale.com>
Signed-off-by: NRobin Gong <b38343@freescale.com>
Acked-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NMark Brown <broonie@kernel.org>

Currently, at module removal, one gets the following warnings:
------------[ cut here ]------------
WARNING: at drivers/clk/clk.c:780 clk_disable+0x18/0x24()
Modules linked in: spi_imx(-) [last unloaded: ev76c560]
CPU: 1 PID: 16337 Comm: rmmod Tainted: G        W    3.10.17-80548-g90191eb-dirty #33
[<80013b4c>] (unwind_backtrace+0x0/0xf8) from [<800115dc>] (show_stack+0x10/0x14)
[<800115dc>] (show_stack+0x10/0x14) from [<800257b8>] (warn_slowpath_common+0x4c/0x68)
[<800257b8>] (warn_slowpath_common+0x4c/0x68) from [<800257f0>] (warn_slowpath_null+0x1c/0x24)
[<800257f0>] (warn_slowpath_null+0x1c/0x24) from [<803f60ec>] (clk_disable+0x18/0x24)
[<803f60ec>] (clk_disable+0x18/0x24) from [<7f02c9cc>] (spi_imx_remove+0x54/0x9c [spi_imx])
[<7f02c9cc>] (spi_imx_remove+0x54/0x9c [spi_imx]) from [<8025868c>] (platform_drv_remove+0x18/0x1c)
[<8025868c>] (platform_drv_remove+0x18/0x1c) from [<80256f60>] (__device_release_driver+0x70/0xcc)
[<80256f60>] (__device_release_driver+0x70/0xcc) from [<80257770>] (driver_detach+0xcc/0xd0)
[<80257770>] (driver_detach+0xcc/0xd0) from [<80256d90>] (bus_remove_driver+0x7c/0xc0)
[<80256d90>] (bus_remove_driver+0x7c/0xc0) from [<80068668>] (SyS_delete_module+0x144/0x1f8)
[<80068668>] (SyS_delete_module+0x144/0x1f8) from [<8000e080>] (ret_fast_syscall+0x0/0x30)
---[ end trace 1f5df9ad54996300 ]---
------------[ cut here ]------------
WARNING: at drivers/clk/clk.c:780 clk_disable+0x18/0x24()
Modules linked in: spi_imx(-) [last unloaded: ev76c560]
CPU: 1 PID: 16337 Comm: rmmod Tainted: G        W    3.10.17-80548-g90191eb-dirty #33
[<80013b4c>] (unwind_backtrace+0x0/0xf8) from [<800115dc>] (show_stack+0x10/0x14)
[<800115dc>] (show_stack+0x10/0x14) from [<800257b8>] (warn_slowpath_common+0x4c/0x68)
[<800257b8>] (warn_slowpath_common+0x4c/0x68) from [<800257f0>] (warn_slowpath_null+0x1c/0x24)
[<800257f0>] (warn_slowpath_null+0x1c/0x24) from [<803f60ec>] (clk_disable+0x18/0x24)
[<803f60ec>] (clk_disable+0x18/0x24) from [<7f02c9e8>] (spi_imx_remove+0x70/0x9c [spi_imx])
[<7f02c9e8>] (spi_imx_remove+0x70/0x9c [spi_imx]) from [<8025868c>] (platform_drv_remove+0x18/0x1c)
[<8025868c>] (platform_drv_remove+0x18/0x1c) from [<80256f60>] (__device_release_driver+0x70/0xcc)
[<80256f60>] (__device_release_driver+0x70/0xcc) from [<80257770>] (driver_detach+0xcc/0xd0)
[<80257770>] (driver_detach+0xcc/0xd0) from [<80256d90>] (bus_remove_driver+0x7c/0xc0)
[<80256d90>] (bus_remove_driver+0x7c/0xc0) from [<80068668>] (SyS_delete_module+0x144/0x1f8)
[<80068668>] (SyS_delete_module+0x144/0x1f8) from [<8000e080>] (ret_fast_syscall+0x0/0x30)
---[ end trace 1f5df9ad54996301 ]---

Since commit 9e556dcc, "spi: spi-imx: only
enable the clocks when we start to transfer a message", clocks are always
disabled except when transmitting messages.  There is thus no need to
disable them at module removal.

Fixes: 9e556dcc (spi: spi-imx: only enable the clocks when we start to transfer a message)
Signed-off-by: NPhilippe De Muyter <phdm@macqel.be>
Acked-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org

Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NMark Brown <broonie@linaro.org>

No need to return a 'fake' return value on platform_get_irq() failure.

Just return the error code itself instead.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Calling init_completion() once is enough.
For the rest of the iterations, call reinit_completion() instead.
Signed-off-by: NAxel Lin <axel.lin@ingics.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>

Problem:
--------
 The problem this patch addresses has the following assumptions about the
 SPI bus setup:
 - The hardware used to find this is Freescale i.MX537 @ 1200MHz
 - The SPI SCLK operate at very low speed, less than 200 kHz
 - There are two SPI devices attached to the bus
   - Each device uses different GPIO for chipselect
   - Each device requires different SCLK signal polarity

 The observation of the SCLK and GPIO chipselect lines with a logic analyzer
 shows, that the SCLK polarity change does sometimes happen after the GPIO
 chipselect is asserted. The SPI slave device reacts on that by counting the
 SCLK polarity change as a clock pulse, which disrupts the communication with
 the SPI slave device.

Explanation:
------------
 We found an interesting correlation, that the maximum delay between the write
 into the ECSPIx_CONFIGREG register and the change of SCLK polarity at each
 SCLK frequency of 10 kHz, 20 kHz, 50 kHz and 100 kHz is 100 uS, 50 uS, 20 uS
 and 10 uS respectively. This lead us to a theory, that at SCLK frequency of
 1 Hz, the delay would be 1 S. Therefore, the time it takes for the write to
 ECSPIx_CONFIGREG to take effect in the hardware is up to the duration of 1
 tick of the SCLK clock.

 During this delay period, if the SCLK frequency is too low, the execution of
 the spi-imx.c driver can advance so much, that the GPIO chipselect will be
 asserted. The GPIO chipselect is asserted almost immediatelly.

Solution:
---------
 The solution this patch presents is simple. We calculate the resulting SCLK
 clock first by dividing the ECSPI block clock by both dividers that are to be
 programmed into the configuration register. Based on the resulting SCLK clock,
 we derive the delay it will take for the changes to get really applied. We are
 extra careful here so we delay twice as long as we should. Note that the patch
 does not create additional overhead at high speeds as the delay will likely be
 close to zero there.
Signed-off-by: NMarek Vasut <marex@denx.de>
To: linux-spi@vger.kernel.org
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Huang Shijie <b32955@freescale.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

Current code keeps the clocks enabled all the time, it wastes the power
when there is no operaiton on the spi controller.

In order to save the power, this patch adds the two hooks:
   spi_imx_prepare_message: enable the clocks for this message
   spi_imx_unprepare_message: disable the clocks.

This patch also disables the clocks in the end of the probe.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Many drivers that use bitbang library have a leak on probe error paths.
This is because once a spi_master_get() call succeeds, we need an additional
spi_master_put() call to free the memory.

Fix this issue by moving the code taking a reference to master to
spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on
success. With this change, the caller is responsible for calling
spi_bitbang_stop() to decrement the reference and spi_master_put() as
counterpart of spi_alloc_master() to prevent a memory leak.

So now we have below patten for drivers using bitbang library:

probe:
spi_alloc_master        -> Init reference count to 1
spi_bitbang_start       -> Increment reference count
remove:
spi_bitbang_stop        -> Decrement reference count
spi_master_put          -> Decrement reference count (reference count reaches 0)

Fixup all users accordingly.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Suggested-by: NUwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Acked-by: NUwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

Many drivers that use bitbang library have a leak on probe error paths.
This is because once a spi_master_get() call succeeds, we need an additional
spi_master_put() call to free the memory.

Fix this issue by moving the code taking a reference to master to
spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on
success. With this change, the caller is responsible for calling
spi_bitbang_stop() to decrement the reference and spi_master_put() as
counterpart of spi_alloc_master() to prevent a memory leak.

So now we have below patten for drivers using bitbang library:

probe:
spi_alloc_master        -> Init reference count to 1
spi_bitbang_start       -> Increment reference count
remove:
spi_bitbang_stop        -> Decrement reference count
spi_master_put          -> Decrement reference count (reference count reaches 0)

Fixup all users accordingly.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Suggested-by: NUwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Acked-by: NUwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

Enable auto loading by udev when spi-imx is compiled as a module.
Signed-off-by: NNiels de Vos <ndevos@redhat.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

clk_prepare_enable() may fail, so let's check its return value and propagate it
in the case of error.

While at it, fix the order of clk_disable_unprepare calls: clk_ipg should be
disabled first, followed by clk_per.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Using devm functions can make the code smaller and cleaner.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Fix compilation error due to a typo introduced by commit 24778be2
("spi: convert drivers to use bits_per_word_mask"). Without this patch
we get the following build errors:

drivers/spi/spi-imx.c: In function ‘spi_imx_setupxfer’:
drivers/spi/spi-imx.c:703:2: warning: no return statement in function returning non-void [-Wreturn-type]
drivers/spi/spi-imx.c: At top level:
drivers/spi/spi-imx.c:705:9: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘->’ token
drivers/spi/spi-imx.c:707:2: error: expected identifier or ‘(’ before ‘return’
drivers/spi/spi-imx.c:708:1: error: expected identifier or ‘(’ before ‘}’ token
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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>

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: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d063
(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: NJingoo Han <jg1.han@samsung.com>
Acked-by: NGrant Likely <grant.likely@linaro.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Add an entry for MODULE_ALIAS().
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

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>

There are SPI devices which need a SPI clock with active low polarity and
high inactive state.

Add the setting of the inactive state ECSPIx_CONFIGREG:SCLK CTL
according to the clock polarity ECSPIx_CONFIGREG:SCLK POL:

DT without "spi-cpol" = 0 = clock active high polarity = inactive state low
DT with    "spi-cpol" = 1 = clock active low  polarity = inactive state high
Signed-off-by: NKnut Wohlrab <knut.wohlrab@de.bosch.com>
Signed-off-by: NDirk Behme <dirk.behme@de.bosch.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
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 imx 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: NMauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: NSascha Hauer <kernel@pengutronix.de>
Acked-by: NVinod Koul <vinod.koul@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Dan Williams <djbw@fb.com>
Cc: "Ben Dooks (embedded platforms)" <ben-linux@fluff.org>
Cc: "Wolfram Sang (embedded platforms)" <w.sang@pengutronix.de>
Cc: Chris Ball <cjb@laptop.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Liam Girdwood <lrg@ti.com>
Cc: Javier Martin <javier.martin@vista-silicon.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

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

	drivers/spi/spi-imx.c: In function spi_imx_probe:
	drivers/spi/spi-imx.c:814:24: warning: assignment discards const qualifier from pointer target type [enabled by default]
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>

Use gpio_is_valid() to replace "gpio >= 0" or "gpio < 0".

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NHui Wang <jason77.wang@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The config.speed_hz is just setted at the two lines ahead of it,
obviously we don't need to copy the code to set the config.speed_hz
again. Remove it for a cleanup.

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NHui Wang <jason77.wang@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Cc: spi-devel-general@lists.sourceforge.net
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NDong Aisheng <dong.aisheng@linaro.org>

the current i.MX clock support groups together unrelated clocks
to a single clock which is then used by the driver. This can't
be accomplished with the generic clock framework so we instead
request the individual clocks in the driver. For i.MX there are
generally three different clocks:

ipg: bus clock (needed to access registers)
ahb: dma relevant clock, sometimes referred to as hclk in the datasheet
per: bit clock, pixel clock

This patch changes the driver to request the individual clocks.
Currently all clk_get will get the same clock until the SoCs
are converted to the generic clock framework
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

When no platform_data is present and either 'spi-num-chipselects' is
not defined in the DT or 'cs-gpios' has less entries than
'spi-num-chipselects' specifies, the NULL platform_data pointer is
being dereferenced.
Signed-off-by: NLothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

This fixes 36 sparse warnings like:

	drivers/spi/spi-imx.c:143:1: warning: incorrect type in argument 1 (different address spaces)
	drivers/spi/spi-imx.c:143:1:    expected void const volatile [noderef] <asn:2>*<noident>
	drivers/spi/spi-imx.c:143:1:    got void *
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Simplify the error handling by moving the code to free gpios in one place.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

For simple modules that contain a single platform_driver without any
additional setup code then ends up being a block of duplicated
boilerplate.  This patch adds a new macro, module_platform_driver(),
which replaces the module_init()/module_exit() registrations with
template functions.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Reviewed-by: NMagnus Damm <magnus.damm@gmail.com>
Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>

commit 22a85e4c (spi/imx: add device tree probe support) broke spi-imx usage
when the SPI chipselect is the one internal to the controller.

On a mx31pdk board the following error is seen:

Registering mxc_nand as whole device
------------[ cut here ]------------
WARNING: at drivers/gpio/gpiolib.c:101 gpio_ensure_requested+0x4c/0xf4()
autorequest GPIO-0
Modules linked in:
[<c0014410>] (unwind_backtrace+0x0/0xf4) from [<c0025754>] (warn_slowpath_common+0x4c/0x64)
[<c0025754>] (warn_slowpath_common+0x4c/0x64) from [<c0025800>] (warn_slowpath_fmt+0x30/0x40)
[<c0025800>] (warn_slowpath_fmt+0x30/0x40) from [<c0198688>] (gpio_ensure_requested+0x4c/0xf4)
[<c0198688>] (gpio_ensure_requested+0x4c/0xf4) from [<c01988c8>] (gpio_direction_output+0xa0/0x138)
[<c01988c8>] (gpio_direction_output+0xa0/0x138) from [<c01ed198>] (spi_imx_setup+0x38/0x4c)
[<c01ed198>] (spi_imx_setup+0x38/0x4c) from [<c01eb5d0>] (spi_setup+0x38/0x50)
[<c01eb5d0>] (spi_setup+0x38/0x50) from [<c01eb85c>] (spi_add_device+0x94/0x124)
[<c01eb85c>] (spi_add_device+0x94/0x124) from [<c01eb960>] (spi_new_device+0x74/0xac)
[<c01eb960>] (spi_new_device+0x74/0xac) from [<c01eb9b8>] (spi_match_master_to_boardinfo+0x20/0x40)
[<c01eb9b8>] (spi_match_master_to_boardinfo+0x20/0x40) from [<c01eba88>] (spi_register_master+0xb0/0x104)
[<c01eba88>] (spi_register_master+0xb0/0x104) from [<c01ec0b4>] (spi_bitbang_start+0x104/0x17c)
[<c01ec0b4>] (spi_bitbang_start+0x104/0x17c) from [<c02c2c4c>] (spi_imx_probe+0x2fc/0x404)
[<c02c2c4c>] (spi_imx_probe+0x2fc/0x404) from [<c01c2498>] (platform_drv_probe+0x18/0x1c)
[<c01c2498>] (platform_drv_probe+0x18/0x1c) from [<c01c1058>] (driver_probe_device+0x78/0x174)
[<c01c1058>] (driver_probe_device+0x78/0x174) from [<c01c11e0>] (__driver_attach+0x8c/0x90)
[<c01c11e0>] (__driver_attach+0x8c/0x90) from [<c01c0860>] (bus_for_each_dev+0x60/0x8c)
[<c01c0860>] (bus_for_each_dev+0x60/0x8c) from [<c01c0088>] (bus_add_driver+0xa0/0x288)
[<c01c0088>] (bus_add_driver+0xa0/0x288) from [<c01c179c>] (driver_register+0x78/0x18c)
[<c01c179c>] (driver_register+0x78/0x18c) from [<c0008490>] (do_one_initcall+0x34/0x178)
[<c0008490>] (do_one_initcall+0x34/0x178) from [<c03a5204>] (kernel_init+0x74/0x118)
[<c03a5204>] (kernel_init+0x74/0x118) from [<c000f65c>] (kernel_thread_exit+0x0/0x8)
---[ end trace 759f924b30fd5a44 ]---

Fix this issue by using the original chip select logic and make spi-imx to work again.

Tested on a mx31pdk that uses the hardware SPI chipselect pins and also
on a mx27pdk that uses GPIO as SPI chipselect.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

It adds device tree probe support for spi-imx driver.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

It copies gpio number passed via platform data embedded pointer into
driver private data, so that we do not need to refer to this embedded
pointer passed by platform data after probe function exits.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>