The sg list used to prepare cyclic DMA descriptors is currently
allocated statically on the stack as an array of 32 elements. This makes
the shdma_prep_dma_cyclic() function consume a lot of stack space, as
reported by the compiler:

drivers/dma/sh/shdma-base.c: In function ‘shdma_prep_dma_cyclic’:
drivers/dma/sh/shdma-base.c:715:1: warning: the frame size of 1056 bytes
is larger than 1024 bytes [-Wframe-larger-than=]

Given the limited Linux kernel stack size, this could lead to stack
overflows. Fix the problem by allocating the sg list dynamically.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The shdma_chan_filter() function relies on the DMA channel being
embedded in an shdma_chan structure. If this assumption isn't true, for
instance when the system contains DMA channels supported by an unrelated
driver, the function will crash.

Avoid this by returning false directly when the channel belongs to an
unrelated device.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Separate helpers and drivers in the Kconfig and Makefile to improve
readability and move the CONFIG_OF dependency from the Makefile to
Kconfig.

[pebolle@tiscali.nl: reported need to rename SHDMA_R8A73A4 instances]
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
[horms+renesas@verge.net.au: squashed rename of SHDMA_R8A73A4 instances]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The sun6i_dma_prep_memcpy and sun6i_dma_prep_slave_sg functions were both
leaking the descriptor they allocated if an  error was happening after a
successful dma_pool_alloc call.

It also fixes a memleak that was happening in the scatter gather list
traversal, that was allocating as much descriptor as there was scatter gather
items, but only freeing the current descriptor if an error was to arise.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

There's still a small window between the call to sun6i_kill_tasklet and the end
of the driver remove function where a spurious interrupt might trigger, and
start using deallocated resources.

Replace the call to synchronize_irq by a free_irq, so that we're sure that we
won't get any further interrupts when we're deallocating resources.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Since the conversion routine is quite trivial, we don't need this switch, and
we can just use a simple calculation.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Select DMA_ENGINE when DMA_OF is selected since
of_dma_xlate_by_chan_id() from drivers/dma/of-dma.c uses
dma_get_slave_channel() from drivers/dma/dmaengine.c

This resolves error reported:

drivers/built-in.o: In function `of_dma_xlate_by_chan_id':
drivers/dma/of-dma.c:253: undefined reference to `dma_get_slave_channel'
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Move the DMA channel used in cyclic mode (audio) to the highest priority
event queue which helps to reduce audio problems.
When the channel is terminated, move it back to the default queue.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

In some cases it is desired to move a channel to a specific event queue.
Such a use case is audio, where it is preferred that it is served with
highest priority compared to other DMA clients.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Use the lowest priority queue as default for clients.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

If the client (audio) does not request interrupts for every period we can
disable them.
With updated audio driver stack we can play audio w/o the need to process
any edma interrupts.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The edma can report accurate DMA position so update the residue_granularity
to DMA_RESIDUE_GRANULARITY_BURST.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The sg_dma_len() returns unsigned int but we had driver print it as %zu, use
%u as documented in Documentation/printk-formats.txt

drivers/dma/sun6i-dma.c: In function ‘sun6i_dma_prep_slave_sg’:
drivers/dma/sun6i-dma.c:643: warning: format ‘%zu’ expects type ‘size_t’,
but argument 8 has type ‘unsigned int’
drivers/dma/sun6i-dma.c:661: warning: format ‘%zu’ expects type ‘size_t’,
but argument 8 has type ‘unsigned int’
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Since the driver defined COMPILE_TEST, it gets compiled for different arch's
The driver uses __virt_to_phys() insteadof virt_to_phys, so replace it

drivers/dma/sun6i-dma.c: In function ‘sun6i_dma_dump_chan_regs’:
drivers/dma/sun6i-dma.c:203: error: implicit declaration of function '__virt_to_phys'
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Register the controller for device tree based lookup of DMA channels
(non-fatal for backwards compatibility with older device trees) and
provide the '#dma-cells' property in the shared mpc5121.dtsi file
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

This patch adds a new common OF dma xlate callback function which will match a
channel by it's id. The binding expects one integer argument which it will use to
lookup the channel by the id.

Unlike of_dma_simple_xlate this function is able to handle a system with
multiple DMA controllers. When registering the of dma provider with
of_dma_controller_register a pointer to the dma_device struct which is
associated with the dt node needs to passed as the data parameter.
New function will use this pointer to match only channels which belong to the
specified DMA controller.
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Introduce a device tree binding document for the MPC512x DMA controller
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The Allwinner A31 has a 16 channels DMA controller that it shares with the
newer A23. Although sharing some similarities with the DMA controller of the
older Allwinner SoCs, it's significantly different, I don't expect it to be
possible to share the driver for these two.

The A31 Controller is able to memory-to-memory or memory-to-device transfers on
the 16 channels in parallel.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The Allwinner A31 DMA controller is rather simple to describe in the DT. Add
the bindings documentation.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Commit - 653e67f7: "dmaengine: inherit debug settings from the subsystem
for subdirectories" introduced debug option for subdirectories too
This exposed issue with ipu driver not using return value

For now just warn users about it
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Per license_is_gpl_compatible(), the MODULE_LICENSE() string for GPL v2 is
"GPL v2", not "GPLv2".  Use "GPL v2" so this module doesn't taint the
kernel.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

As of commit commit f04cd407 ("fsldma: fix
controller lockups"), its last (and only ever) user is gone.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com>
Tested-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Shared Peripheral ASRC, running on SPBA, needs to use shp sciprts for
DMA transfer. So this patch just adds a new DMATYPE for it.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The filter() function is currently called by xlate() while it transfers
imx_dma_data as a local variable to the filter() but releases the data
right after returning a DMA channel pointer, which results chan->private
pointing an invalid memory space.

So this patch just stores the imx_dma_data into sdmac to make usre the
private pointer valid as long as the channel exists.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Commit 6079d38c ("dmaengine: pl330: Remove useless xfer_cb indirection")
removed the __callback() function which created an unnecessary level of
indirection to execute the tranfer callback .xfer_cb

Unfortunately the commit also changed the semantics slightly since that
function used to check if the request was not NULL before attempting to
execute the callback function. Not checking this could lead to a kernel
NULL pointer dereference error.
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Accordingly to discussion [1] and followed up documentation the DMA controller
driver shouldn't start any DMA operations when dmaengine_submit() is called.

This patch fixes the workflow in dw_dmac driver to follow the documentation.

[1] http://www.spinics.net/lists/arm-kernel/msg125987.htmlSigned-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

It would be useful to know when the first descriptor in the queue is started
along with its cookie.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

We have a duplicate code which starts first descriptor in the queue. Let's make
this as a separate helper that can be used in future as well.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The DMA40 device tree documentation was vague on the second cell passed
in the configuration node for consumers, and did not specify what the
available signals were connected to. Extend the documentation with this
information for the DB8500 ASIC.
Reported-by: Pawel Kulakowski <pawel.kulakowski@tieto.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The pl330_chan_ctrl() function has 3 internal code paths which, except for the
locking, do not share any code outside of their sections. One code path is never
exercised and can be removed. The other two are mostly just forwards to the
_start() and _stop() calls. This patch modifies the code to instead of going via
pl330_chan_ctrl() to call _start() and _stop() directly. This allows to
completely remove pl330_chan_ctrl().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Instead of storing a special instruction in the command buffer to mark a request
as currently unused just set the descriptor field to NULL.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The pl330_req struct is embedded into the dma_pl330_desc struct. But half of the
pl330_req struct are pointers to other fields of the dma_pl330_desc struct it is
embedded to. By directly embedding the fields from the pl330_req struct into the
dma_pl330_desc struct and reworking the code to work with the dma_pl330_desc
struct those pointers can be eliminated. This slightly simplifies the code.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Both the dma_pl330_dmac and the pl330_dmac struct have the same lifetime and the
separation of them is a relict of this having been two different drivers in the
past. Merging them into one struct makes the code a bit simpler as it for
example allows to remove the pointers going back and forth between the two
structs.

While we are at it also directly embed the pl330_info struct into the
pl330_dmac struct as this allows to remove some more redundant fields.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Since we keep a pointer to the manager thread it is fairly easy to check if a
thread is the manager thread.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

We know that we do not create invalid ccr settings in this driver. There is no
need to validate them.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The pl330_chid field of the dma_pl330_chan struct always holds a pointer to the
thread that is associated with the channel. Changing its type form void * to
struct pl330_thread makes things more type safe and removes the need for
unnecessary typecasts. While we are at it also rename the field from the cryptic
pl330_chid to thread.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>