When running in software cyclic mode the driver currently does not go back
to the first segment once the last segment has been reached. Effectively
making the transfer non-cyclic.
Fix this by going back to the first segment once the last segment has been
reached for cyclic transfers.
Special care need to be taken to avoid a segment from being submitted
multiple times concurrently, which could happen for transfers with a number
of segments that is smaller than the DMA controller's internal queue.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
In hardware cyclic mode the submitted segment is repeated. This means
hardware cyclic mode can only be used if the transfer has a single segment.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Return IRQ_NONE in the interrupt handler when it is called but no IRQs are
pending. This allows the system to recover in case of an interrupt storm
e.g. due to a wrong interrupt configuration setup.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Propagate errors returned by platform_get_irq() to the driver core. This
will enable proper probe deferring for the driver in case the IRQ provider
has not been registered yet.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Add MODULE_DEVICE_TABLE() for the axi-dmac driver. This allows the driver
to be loaded on demand when built as a module.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Implement the new device_synchronize() callback to allow proper
synchronization when stopping a channel. Since the driver already makes
sure that no new complete callbacks are scheduled after the
device_terminate_all() callback has been called, all left to do in the
device_synchronize() callback is to wait for all currently running complete
callbacks to finish.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Add support for the Analog Devices AXI-DMAC DMA controller. This controller
is a soft peripheral that can be instantiated in a FPGA and is often used
in Analog Devices' reference designs for FPGA platforms.
The peripheral has various configuration options that can be selected at
synthesis time and influence the supported features of the instantiated
peripheral, those options are represented as device-tree properties to
allow the driver to behave accordingly.
The peripheral has a zero latency architecture, which means it is possible
to switch from one to the next descriptor without any delay. This is
archived by having a internal queue which can hold multiple descriptors.
The driver supports this, which means it will submit new descriptors
directly to the hardware until the queue is full and not wait for a
descriptor to complete before the next one is submitted. Interrupts are
used for the descriptor queue flow control.
Currently the driver supports SG, cyclic and interleaved slave DMA.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
