SPI core has a comprehensive function set to map and unmap a message when it's
needed. This patch converts driver to use that advantage.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch shuts up any ongoing DMA transfer in case of error.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The patch splits DMA preparatory code to dma_setup() callback. The change also
converts transfer_one() to program DMA whenever the transfer is DMA mapped. The
change is a follow up of the converion to use SPI core transfer_one_message().
Since the DMA mapped transfers can be interleaved with PIO ones the DMA related
configuration should respect that.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

DMAEngine has a specific type to be used for bus width. This patch converts the
code to use the values of the specific type when configure DMA transfer.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch removes a lot of duplicate code since SPI core provides a nice
message handling.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch refactors the code in pump_transfers() to reprogram the registers
immediately when we have a new configuration data. The behaviour is slightly
modified:
 - chip is always disabled and reenabled
 - CTRL0 is always reprogrammed

This change allows to do a further refactoring and simplier conversion to use
SPI core DMA routines in the future.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The error handling is partially broken since the controller is disabled on
error and is not re-enabled until condition occurs, i.e. mode (poll, PIO/DMA),
chip (cs_change), or speed (clk_div) is changed. In the result of these changes
we will have a predictable state of the SPi controller independently on how
successfull was a previous transfer.

The patch disables interrupts and re-enables the SPI controller wherever it
needs to be done. Thus most of the time the SPI controller is kept enabled. The
runtime PM, when it will be implemented, must take care of the controller
disabling and re-enabling.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The commit d297933c (spi: dw: Fix detecting FIFO depth) tries to fix the
logic of the FIFO detection based on the description on the comments. However,
there is a slight difference between numbers in TX Level and TX FIFO size.

So, by specification the FIFO size would be in a range 2-256 bytes. From TX
Level prospective it means we can set threshold in the range 0-(FIFO size - 1)
bytes. Hence there are currently two issues:
  a) FIFO size 2 bytes is actually skipped since TX Level is 1 bit and could be
     either 0 or 1 byte;
  b) FIFO size is incorrectly decreased by 1 which already done by meaning of
     TX Level register.

This patch fixes it eventually right.

Fixes: d297933c (spi: dw: Fix detecting FIFO depth)
Reviewed-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

Instead of an additional reading from the register let's update it even if the
value is kept the same.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch does the following changes:

a) the calculation of clk_div is simplified to oneliner;

b) chip->clk_div is updated if clk_div is not zero, therefore the condition is
   simplified by using chip->clk_div in both cases;

c) while here, the redundant parentheses are removed.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

There is no need to have an additional variable to get a TX level. The patch
refactors this piece of code.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

There is no sense to keep a member assignment in the internal structure inside
the condition which reprograms HW. It makes code readability better if kept
outside of the condition.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

When autodetection is used it would be useful to know what the FIFO size is.
The patch adds a debug message for this purpose.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

In case of warning message in ->probe() we have to use HW device name instead
of master because last is not defined yet.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Current code tries to find the highest valid fifo depth by checking the value
it wrote to DW_SPI_TXFLTR. There are a few problems in current code:
1) There is an off-by-one in dws->fifo_len setting because it assumes the latest
   register write fails so the latest valid value should be fifo - 1.
2) We know the depth could be from 2 to 256 from HW spec, so it is not necessary
   to test fifo == 257. In the case fifo is 257, it means the latest valid
   setting is fifo = 256. So after the for loop iteration, we should check
   fifo == 2 case instead of fifo == 257 if detecting the FIFO depth fails.
This patch fixes above issues.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Reviewed-and-tested-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

An IOCTL call that calls spi_setup() and then dw_spi_setup() will
overwrite the persisted last transfer speed. On each transfer, the
SPI speed is compared to the last transfer speed to determine if the
clock divider registers need to be updated (did the speed change?).
This bug was observed with the spidev driver using spi-config to
update the max transfer speed.

This fix: Don't overwrite the persisted last transaction clock speed
when updating the SPI parameters in dw_spi_setup(). On the next
transaction, the new speed won't match the persisted last speed
and the hardware registers will be updated.
On initialization, the persisted last transaction clock
speed will be 0 but will be updated after the first SPI
transaction.

Move zeroed clock divider check into clock change test because
chip->clk_div is zero on startup and would cause a divide-by-zero
error. The calculation was wrong as well (can't support odd #).
Reported-by: NVlastimil Setka <setka@vsis.cz>
Signed-off-by: NVlastimil Setka <setka@vsis.cz>
Signed-off-by: NThor Thayer <tthayer@opensource.altera.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

The of_node element must be initialized to enable discovery of node
children which takes place in the of_register_spi_devices() function.
Signed-off-by: NThor Thayer <tthayer@opensource.altera.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Make comments be surrounded by spaces and move part of code to one line where
it suits 80 characters.

There is no functional changes.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

For testing purposes it's good to have a loopback mode enabled. The patch adds
necessary bits for that.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Since driver is used on other platforms and debugfs stuff would be useful there
as well let's substitute mrst_ by dw_ where it suits. Additionally let's use
SPI master device name when print registers dump.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

There is no need to keep FSF address in the head of the file. While here, fix
few typos in the header.

There is no functional change.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Fix the following checkpatch warnings.

  WARNING: debugfs_remove_recursive(NULL) is safe this check is probably not required
  WARNING: min() should probably be min_t(u32, rx_left, dw_readw(dws, DW_SPI_RXFLR))
  WARNING: else is not generally useful after a break or return
  WARNING: Missing a blank line after declarations
  WARNING: void function return statements are not generally useful
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

device_add() expects that any memory allocated via devm_* API is only
done in the device's probe function.

Fix below boot warning:
WARNING: CPU: 1 PID: 1 at drivers/base/dd.c:286 driver_probe_device+0x2b4/0x2f4()
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 3.16.0-10474-g835c90b-dirty #160
[<c0016364>] (unwind_backtrace) from [<c001251c>] (show_stack+0x20/0x24)
[<c001251c>] (show_stack) from [<c04eaefc>] (dump_stack+0x7c/0x98)
[<c04eaefc>] (dump_stack) from [<c0023d4c>] (warn_slowpath_common+0x78/0x9c)
[<c0023d4c>] (warn_slowpath_common) from [<c0023d9c>] (warn_slowpath_null+0x2c/0x34)
[<c0023d9c>] (warn_slowpath_null) from [<c0302c60>] (driver_probe_device+0x2b4/0x2f4)
[<c0302c60>] (driver_probe_device) from [<c0302d90>] (__device_attach+0x50/0x54)
[<c0302d90>] (__device_attach) from [<c0300e60>] (bus_for_each_drv+0x54/0x9c)
[<c0300e60>] (bus_for_each_drv) from [<c0302958>] (device_attach+0x84/0x90)
[<c0302958>] (device_attach) from [<c0301f10>] (bus_probe_device+0x94/0xb8)
[<c0301f10>] (bus_probe_device) from [<c03000c0>] (device_add+0x434/0x4fc)
[<c03000c0>] (device_add) from [<c0342dd4>] (spi_add_device+0x98/0x164)
[<c0342dd4>] (spi_add_device) from [<c03444a4>] (spi_register_master+0x598/0x768)
[<c03444a4>] (spi_register_master) from [<c03446b4>] (devm_spi_register_master+0x40/0x80)
[<c03446b4>] (devm_spi_register_master) from [<c0346214>] (dw_spi_add_host+0x1a8/0x258)
[<c0346214>] (dw_spi_add_host) from [<c0346920>] (dw_spi_mmio_probe+0x1d4/0x294)
[<c0346920>] (dw_spi_mmio_probe) from [<c0304560>] (platform_drv_probe+0x3c/0x6c)
[<c0304560>] (platform_drv_probe) from [<c0302a98>] (driver_probe_device+0xec/0x2f4)
[<c0302a98>] (driver_probe_device) from [<c0302d3c>] (__driver_attach+0x9c/0xa0)
[<c0302d3c>] (__driver_attach) from [<c0300f0c>] (bus_for_each_dev+0x64/0x98)
[<c0300f0c>] (bus_for_each_dev) from [<c0302518>] (driver_attach+0x2c/0x30)
[<c0302518>] (driver_attach) from [<c0302134>] (bus_add_driver+0xdc/0x1f4)
[<c0302134>] (bus_add_driver) from [<c03035c8>] (driver_register+0x88/0x104)
[<c03035c8>] (driver_register) from [<c030445c>] (__platform_driver_register+0x58/0x6c)
[<c030445c>] (__platform_driver_register) from [<c0700f00>] (dw_spi_mmio_driver_init+0x18/0x20)
[<c0700f00>] (dw_spi_mmio_driver_init) from [<c0008914>] (do_one_initcall+0x90/0x1d4)
[<c0008914>] (do_one_initcall) from [<c06d7d90>] (kernel_init_freeable+0x178/0x248)
[<c06d7d90>] (kernel_init_freeable) from [<c04e687c>] (kernel_init+0x18/0xfc)
[<c04e687c>] (kernel_init) from [<c000ecd8>] (ret_from_fork+0x14/0x20)
Reported-by: NThor Thayer <tthayer@opensource.altera.com>
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

The obvious fix after the commit d9c73bb8 "spi: dw: add support for gpio
controlled chip select". This patch fixes the issue by using locally defined
temporary variable.

Fixes: d9c73bb8 (spi: dw: add support for gpio controlled chip select)
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
Cc: <stable@vger.kernel.org>

The dw_spi_cleanup() function was removed by commit c63f5da0
"spi: dw: Don't call kfree for memory allocated by devm_kzalloc".

commit ec37e8e1 "spi: dw: migrate to generic queue infrastructure" added
dw_spi_cleanup() but never use it. So now I got below build warning:

  CC [M]  drivers/spi/spi-dw.o
drivers/spi/spi-dw.c:609:13: warning: 'dw_spi_cleanup' defined but not used [-Wunused-function]
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NMark Brown <broonie@linaro.org>

Also, use this opportunity to let spi_chip_sel() handle chip-select
deactivation as well.
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NMark Brown <broonie@linaro.org>

Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NMark Brown <broonie@linaro.org>

With devm_kzalloc, the memory is automatically freed when spi_device detach from
the bus.

Fixes: commit 43f627ac (spi: dw: fix memory leak on error path)
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NMark Brown <broonie@linaro.org>
Cc: stabe@vger.kernel.org

Set master->max_speed_hz then spi core will handle checking transfer speed.
So we can remove the same checking in this driver.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NMark Brown <broonie@linaro.org>

Migrate mmio code and core driver to managed resources to reduce boilerplate
error handling code. Also, handle clk_enable() failure while at it, and drop
unused dw_spi iolen field.
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NMark Brown <broonie@linaro.org>

Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
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>

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>

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>

Many users of debugfs copy the implementation of default_open() when
they want to support a custom read/write function op.  This leads to a
proliferation of the default_open() implementation across the entire
tree.

Now that the common implementation has been consolidated into libfs we
can replace all the users of this function with simple_open().

This replacement was done with the following semantic patch:

<smpl>
@ open @
identifier open_f != simple_open;
identifier i, f;
@@
-int open_f(struct inode *i, struct file *f)
-{
(
-if (i->i_private)
-f->private_data = i->i_private;
|
-f->private_data = i->i_private;
)
-return 0;
-}

@ has_open depends on open @
identifier fops;
identifier open.open_f;
@@
struct file_operations fops = {
...
-.open = open_f,
+.open = simple_open,
...
};
</smpl>

[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We are clipping down the presence of module.h, since it was
everywhere.  If you really need it, you better call it out,
as per this changeset.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

The dw_{read,write}[lw] macros produce sparse warnings everytime they
are used.  The "read" ones cause:

warning: cast removes address space of expression
warning: incorrect type in argument 1 (different address spaces)
   expected void const volatile [noderef] <asn:2>*addr
   got unsigned int *<noident>

And the "write" ones:

warning: cast removes address space of expression
warning: incorrect type in argument 2 (different address spaces)
   expected void volatile [noderef] <asn:2>*addr
   got unsigned int *<noident>

Fix this by removing struct dw_spi_reg and converting all the register
offsets to #defines. Then convert the macros into inlined functions so
that proper type checking can occur.

While here, also fix the three sparse warnings in spi-dw-mid.c due to
the return value of ioremap_nocache being stored in a u32 * not a
void __iomem *.

With these changes the spi-dw* files all build with no sparse warnings.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: NFeng Tang <feng.tang@intel.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Signed-off-by: NShuoX Liu <shuox.liu@intel.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>