In general ~0 does not fit some integer types. Let's do a helper to make a
comparison with that constant properly.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

To simplify the driver development let's split driver to library and platform
code parts. It helps us to add PCI driver in future.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
[Fixed compile error and few checkpatch issues]
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The dw_dmac driver is going to be split into multiple files. To make this more
convenient move it to an own directory.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

EXPORT_SYMBOL and inline directives are contradictory to each other.
The patch fixes this inconsistency.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NDenis Efremov <yefremov.denis@gmail.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Since we have proper ACPI DMA helpers implemented, the driver may use it. This
patch introduces custom filter function together with acpi_device_id table.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

If CONFIG_OF is not set the of_node of the device will always be NULL.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The patch to add the common DMA binding added a dummy dw_dma_slave
structure into the dw_dma_chan structure in order to configure the
masters correctly. It turns out that this can be simplified if we
pick the DMA masters in the dwc_alloc_chan_resources function instead
and save them in the dw_dma_chan structure directly.

This could be simplified further once all users that today use
dw_dma_slave for configuration get converted to device tree based
setup instead.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Since we will have not only DT cases in future let's rename DT related methods
to reflect their belonging.

The rename was done as follows:
	struct dw_dma_filter_args	-> struct dw_dma_of_filter_args
	dw_dma_generic_filter()		-> dw_dma_of_filter()
	dw_dma_xlate()			-> dw_dma_of_xlate()
	dw_dma_id_table			-> dw_dma_of_id_table

There is no functional change.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Let's use capital letter as a first one in the comments.
There is no functional changes.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

When we pause the channel after transfer is completed we might stuck in the
dwc_chan_pause() because the FIFO_EMPTY flag will never be asserted. To avoid
the endless loop we introduce a timeout here (*). The proper solution is to
somehow get the residue in FIFO and avoid busyloop when transfer is done, but
this task is not simple and fast.

Unfortunately we can't use cpu_relax() in conjunction with jiffies checker, due
to we have interrupts disabled by spin_lock_irqsave() and there is a big chance
that no interrupts will come to update the jiffies..

(*) The worst case is
	AHB write * FIFO size / hclk = 5.12 us,
    where
	AHB write = 2 cycles,
	hclk = 100 MHz,
	burst size = 1 byte,
	FIFO size = 256 bytes.
    The proposed 40us timeout might be considered as a big one, though we enter
    to that state only when we have the transfer already completed.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

On some hardware configurations we have got the request line with the offset.
The patch introduces convert_slave_id() helper for that cases. The request line
base is came from the driver data provided by the platform_device_id table.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

As reported by Wu Fengguang's build robot tracking sparse warnings, the
dma_spec arguments in the dw_dma_xlate are already byte swapped on
little-endian platforms and must not get swapped again. This code is
currently not used anywhere, but will be used in Linux 3.10 when the
ARM SPEAr platform starts using the generic DMA DT binding.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The original device tree binding for this driver, from Viresh Kumar
unfortunately conflicted with the generic DMA binding, and did not allow
to completely seperate slave device configuration from the controller.

This is an attempt to replace it with an implementation of the generic
binding, but it is currently completely untested, because I do not have
any hardware with this particular controller.

The patch applies on top of the slave-dma tree, which contains both the base
support for the generic DMA binding, as well as the earlier attempt from
Viresh. Both of these are currently not merged upstream however.

This version incorporates feedback from Viresh Kumar, Andy Shevchenko
and Russell King.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Vinod Koul <vinod.koul@linux.intel.com>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

In some cases we got the device without dma_mask configured. We have to apply
the default value to avoid crashes during memory mapping.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Intel Lynxpoint PCH Low Power Subsystem has DMA controller to support general
purpose serial buses like SPI, I2C, and HSUART. This controller is enumerated
from ACPI namespace with ACPI ID INTL9C60.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Currently the driver returns full length of the active descriptor which is
wrong. We have to go throught the active descriptor and substract the length of
each sent children in the chain from the total length along with the actual
data in the DMA channel registers.

The cyclic case is not handled by this patch due to len field in the descriptor
structure is left untouched by the original code.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

It will be useful to have the length of the transfer in the descriptor. The
cyclic transfer functions remained untouched.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

By this new field we distinguish a total length of the chain and the individual
length of each descriptor in the chain.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The soft LLP mode is working for active descriptor only. So, we do not need to
have a copy of its pointer.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

It's usefull to have the values of the DW_PARAMS and DWC_PARAMS printed when
debug mode is enabled.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.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: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The proper place for the main logic of the soft LLP mode is
dwc_scan_descriptors. It prevents to get the transfer unexpectedly aborted in
case the user calls dwc_tx_status.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The driver assumes that hardware has two AHB masters which might not be always
true. In such cases we must not exceed number of the AHB masters present in the
hardware. In the proposed scheme in this patch, we would choose the master with
highest possible number whenever we exceed max AHB masters.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Currently descriptors are allocated from normal cacheable memory and that slows
down filling the descriptors, as we need to call cache_coherency routines
afterwards. It would be better to allocate memory for these descriptors from
DMA_COHERENT memory. This would make code much cleaner too.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The DMA transfer could not be established if previously it was paused and
terminated. In that case the channel's suspend bit remains set that prevents to
transfer anything until channel is resumed.

The patch adds the dwc_chan_resume() call instead of a plain flag assignment.
That clears the DWC_CFGL_CH_SUSP bit as well during termination.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The same information could be extracted from the struct dma_chan.
The patch introduces helper function dwc_get_data_width() as well.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The driver requires a custom slave configuration to be present to be able to
make the slave transfers. Nevertheless, in some cases we need only the request
line as an additional information to the generic slave configuration.  The
request line is provided by slave_id parameter of the dma_slave_config
structure. That's why the custom slave configuration could be optional for such
cases.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Currently the direction value comes from the generic slave configuration
structure and explicitly as a preparation function parameter. The first one is
kinda obsoleted. Thus, we have to store the value passed to the preparation
function somewhere in our structures to be able to use it later. The best
candidate to provide the storage is a custom channel structure. Until now we
still keep and check the direction field of the slave config structure as well.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

If we don't yet have the platform device for the driver when it is being loaded
we fail to probe the driver. So instead of calling probe() directly we call
platform_driver_register(). It will call the probe() immediately if we have the
device but also makes the driver to work on platforms where the platform device
is created later.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

dma_transfer_direction is a normal enum. It means we can't usually use the
values as bit fields. Let's adjust this check and move it above the usage of
the direction parameter, due to the nature of the following usage of it.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

We will use at least the dwc_chan_resume() later.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The "else" keyword in the dw_dma_tasklet is removed as well. All together
simplifies the logic of the code and understanding of what is happening there.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

There is no need to check the callback_required parameter, due to we check the
callback pointer to be a non-NULL.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Otherwise we get a warning in case of CONFIG_DMA_API_DEBUG=y

[   45.775943] WARNING: at lib/dma-debug.c:933 check_unmap+0x5d6/0x6ac()
[   45.782369] dw_dmac dw_dmac.0: DMA-API: device driver failed to check map error[device address=0x00000000356efcc0] [size=28 bytes] [mapped as single]
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The patch allows to probe the device when platform data is absent and hardware
auto configuration is enabled. In that case the default platform data is used
where the channel allocation order is set to ascending, channel priority is set
to ascending, and private property is set to true.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The to_dw_desc() macro helps to retrieve the dw_desc node from the
corresponding list_head structure.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

In case of handling a bad descriptor the dwc_handle_error() will dump a stack
as well. It's a lot more verbose and more likely to get user's attention.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

There is no need to call platform_get_drvdata twice as we have it already in dw
variable.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Change printk(KERN_INFO ..., dev_name(...), ...) to dev_info() as well.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>