Add support for platforms which don't use devicetree yet or have to optionally
support a non-devicetree way to request the DMA channel. The patch adds the
compat_request_channel and compat_filter_fn callbacks to the
snd_dmaengine_pcm_config struct. If the compat_request_channel is implemented it
will be used to request the DMA channel. If not dma_request_channel with
compat_filter_fn as the filter function will be used to request the channel.

The patch also exports the snd_dmaengine_pcm_request_chan() function, since
compat platforms will want to use it to request their DMA channel.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Tested-by: NStephen Warren <swarren@nvidia.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Refactor the dmaengine PCM library to allow the DMA channel to be requested
before opening a PCM substream. snd_dmaengine_pcm_open() now expects a DMA
channel instead of a filter function and filter parameter as its parameters.
snd_dmaengine_pcm_close() is updated to not release the DMA channel. This allows
a dmaengine based PCM driver to request its channels before the substream is
opened.

The patch also introduces two new functions, snd_dmaengine_pcm_open_request_chan()
and snd_dmaengine_pcm_close_release_chan(), which have the same signature and
behaviour of the old snd_dmaengine_pcm_{open,close}() and internally use the new
variants of these functions. All users of snd_dmaengine_pcm_{open,close}() are
updated to use snd_dmaengine_pcm_open_request_chan() and
snd_dmaengine_pcm_close_release_chan().
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Tested-by: NStephen Warren <swarren@nvidia.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

This patch adds a common DMA data struct which can be used by DAI drivers to
communicate their DMA configuration requirements to the DMA pcm driver.  Having
a common data structure for this allows us to implement common functions on top
of them, which can be used by multiple platforms.

This patch also introduces a new function to initialize certain fields of a
dma_slave_config struct from the common DAI DMA data struct.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Tested-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Usually device_fc should be set to false for audio DMAs. Initialize it in a
common place so drivers don't have to do this manually.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Tested-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

These functions were initially added to be able to support some oddball dma
drivers, but all users have been updated to deal with the situation without the
help of snd_dmaengine_pcm_{set,get}_data, so these two functions can be removed.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NLothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

With this parameter added to dmaengine_prep_dma_cyclic() the API will be in
sync with other dmaengine_prep_*() functions.
The dmaengine_prep_dma_cyclic() function primarily used by audio for cyclic
transfer required by ALSA, we use the from audio to ask dma drivers to
suppress interrupts (if DMA_PREP_INTERRUPT is cleared) when it is supported
on the platform.
Signed-off-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>
CC: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: NVinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Currently the sound dmaengine pcm helper functions implement the pcm_pointer
callback by trying to count the number of elapsed periods. This is done by
advancing the stream position in the dmaengine callback by one period.
Unfortunately there is no guarantee that the callback will be called for each
elapsed period. It may be possible that under high system load it is only called
once for multiple elapsed periods. This patch addresses the issue by
implementing support for querying the current stream position directly from the
dmaengine driver. Since not all dmaengine drivers support reporting the stream
position yet the old period counting implementation is kept for now.

Furthermore the new mechanism allows to report the stream position with a
sub-period granularity, given that the dmaengine driver supports this.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NVinod Koul <vinod.koul@intel.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Currently the sound dmaengine pcm helper functions implement the pcm_pointer
callback by trying to count the number of elapsed periods. This is done by
advancing the stream position in the dmaengine callback by one period.
Unfortunately there is no guarantee that the callback will be called for each
elapsed period. It may be possible that under high system load it is only called
once for multiple elapsed periods. This patch renames the current implementation
and documents its shortcomings and that it should not be used anymore in new
drivers.

The next patch will introduce a new snd_dmaengine_pcm_pointer which will be
implemented based on querying the current stream position from the dma device.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by Vinod Koul <vinod.koul@linux.intel.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

commit 4a163c82 added extra parameter to device_prep_dma_cyclic
this is not required if we use the wrapper over cyclic API.

This is split from Alexedre's patch
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Since commit 185ecb5f (dmaengine: add context parameter to prep_slave_sg and prep_dma_cyclic)
prep_dma_cyclic() got an extra context parameter.

Add this new parameter in order to fix the following build error (mxs_defconfig and imx_v4_v5_defconfig):

sound/soc/soc-dmaengine-pcm.c:149:3: error: too few arguments to function 'chan->device->device_prep_dma_cyclic'
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Otherwise a wrong position will be reported after restarting a stream and the
first few samples might be skipped.
Signed-off-by: NMika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

This patch adds a set of functions which are intended to be used when
implementing a dmaengine based sound PCM driver.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NVinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>