dma_request_slave_channel_compat() is meant for drivers that support
both DT and legacy platform device based probing: if DT channel DMA
setup fails, it will fall back to platform data based DMA channel setup,
using hardcoded DMA channel IDs and a filter function.
However, if the DTS doesn't provide a "dmas" property for the device,
the fallback is also used. If the legacy filter function is not
hardcoded in the DMA slave driver, but comes from platform data, it will
be NULL. Then dma_request_slave_channel_compat() will succeed
incorrectly, and return a DMA channel, as a NULL legacy filter function
actually means "all channels are OK", not "do not match".
Later, when trying to use that DMA channel, it will fail with:
rcar-dmac e6700000.dma-controller: rcar_dmac_prep_slave_sg: bad parameter: len=1, id=-22
To fix this, ensure that both the filter function and the DMA channel ID
are not NULL before using the legacy fallback.
Note that some DMA slave drivers can handle this failure, and will fall
back to PIO.
See also commit 056f6c8702 ("dmaengine: shdma: Make dummy
shdma_chan_filter() always return false"), which fixed the same issue
for the case where shdma_chan_filter() is hardcoded in a DMA slave
driver.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Inline function __dma_request_slave_channel_compat() doesn't modify "name"
argument but passes it to dma_request_slave_channel() which already takes
it as a constant.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This adds new descriptor flag for reusing a descriptor by submitting
multiple times by a client, for example video buffer.
Add helper APIs for this as well
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Acked-by:Robert Jarzmik <robert.jarzmik@free.fr>
The current API allows the driver to accelerate memset by using the DMA
controller.
However, it does so over a contiguous memory area, which might proves
inefficient when you have to do it over a non-contiguous yet repititive
pattern, since you have to create a number of descriptors and then submit
each other.
Add a memset operation going over a scatter list to handle such cases in a
single call.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Most drivers need to set constraints on the buffer alignment for async tx
operations. However, even though it is documented, some drivers either use
a defined constant that is not matching what the alignment variable expects
(like DMA_BUSWIDTH_* constants) or fill the alignment in bytes instead of
power of two.
Add a new enum for these alignments that matches what the framework
expects, and convert the drivers to it.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Now that we can have ICGs set for both the source and destination (using
the icg field of struct data_chunk) or for only the source or the
destination (using the dst_icg or src_icg respectively), and that these
fields can be ignored depending on other parameters (src_inc, src_sgl,
etc.), the logic to get the actual ICG value can be quite tricky.
The XDMAC driver was already implementing it, but since we will need it in
other drivers, we can move it to the main header file.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
In interleaved mode, we can expect to have different source and destination
strides.
Add support for such case to dmaengine.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
DMA routers are transparent devices used to mux DMA requests from
peripherals to DMA controllers. They are used when the SoC integrates more
devices with DMA requests then their controller can handle.
DRA7x is one example of such SoC, where the sDMA can hanlde 128 DMA request
lines, but in SoC level it has 205 DMA requests.
The of_dma_router will be registered as of_dma_controller with special
xlate function and additional parameters. The driver for the router is
responsible to craft the dma_spec (in the of_dma_route_allocate callback)
which can be used to requests a DMA channel from the real DMA controller.
This way the router can be transparent for the system while remaining generic
enough to be used in different environments.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Free Software Foundation mailing address has been moved in the past and some
of the addresses here are outdated. Remove them from file headers since the
COPYING file in the kernel sources includes it.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Since commit 7bced39751 ("net_dma: simple removal") removed the net_dma
support entirely, net_dma_find_channel has no users left. Remove the function
entirely.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit 7bce d397 510a ("net_dma: simple removal") removed the net_dma support
entirely but left some functions and prototypes in the dmaengine header.
Remove them.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit 48a9db462d ("drivers/dma: remove unused support for MEMSET
operations") removed support for the memset operation in dmaengine, but left
the fill_aligned field that was supposed to set the buffer alignment for the
memset operations.
Remove that field too.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit 0d5484b1c3 ("dmaengine: Move dma_get_slave_caps()
implementation to dmaengine.c") turned the inline dma_get_slave_caps()
function into an external function without adding an inline stub for the
cases where CONFIG_DMA_ENGINE isn't set. This breaks compilation of
drivers using the DMA engine API when CONFIG_DMA_ENGINE isn't set.
Add an inline stub to fix compilation.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Fixes: 0d5484b1c3 ("dmaengine: Move dma_get_slave_caps() implementation to dmaengine.c")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dma_slave_caps is very important to the generic layers that might interact with
dmaengine, such as ASoC. Unfortunately, it has been added as yet another
dma_device callback, and most of the existing drivers haven't implemented it,
reducing its reliability.
Introduce a generic behaviour to implement this, that rely on both the split of
device_control to derive which functions are supported and on new variables to
be set in the dma_device structure.
These variables holds what used to be the capabilities, that were set
per-channel. However, this proved to be a bit overkill, since every driver
filling these so far were hardcoding it, disregarding which channel was
actually given.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Split out the terminate_all command from device_control to a dma_device
callback. In order to preserve backward capability, still rely on
device_control if no such callback has been implemented.
Eventually, this will allow to create a generic dma_slave_caps callback.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Split out the pause and resume operations to callbacks of their own. In order
to preserve some backwark compatibility, the dmaengine_pause/dmaengine_resume
are still falling back on dmaengine_device_control.
Eventually, that will allow to get the device capabilities in a generic way,
removing the need to implement device_slave_caps.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The fact that the channel configuration is done in device_control is rather
misleading, since it's not really advertised as such, plus, the fact that the
framework exposes a function of its own makes it not really intuitive, while
we're losing the type checking whenever we pass that unsigned long argument.
Add a device_config callback to dma_device, with a fallback on the old
behaviour for now for existing drivers to opt in.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
