Commit Graph

6 Commits

Author SHA1 Message Date
Peter Ujfalusi
ec8b5e48c0 dmaengine: Pass flags via device_prep_dma_cyclic() callback
Change the parameter list of device_prep_dma_cyclic() so the DMA drivers
can receive the flags coming from clients.
This feature can be used during audio operation to disable all audio
related interrupts when the DMA_PREP_INTERRUPT is cleared from the flags.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-09-22 11:12:45 -04:00
Russell King
d94443256f dmaengine: sa11x0-dma: add cyclic DMA support
Add support for cyclic DMA on sa11x0 platforms.  This follows the
discussed behaviour that the callback will be called at some point
after period expires, and may coalesce multiple period expiries into
one callback (due to the tasklet behaviour.)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:16:26 +01:00
Russell King
63fe23c34e dmaengine: sa11x0-dma: fix DMA residue support
The semantics now implemented are:

- If the cookie has completed successfully, the residue will be zero.
- If the cookie is in progress or the channel is paused, it will be the
  number of bytes yet to be transferred. [*]
- If the cookie is queued, it will be the number of bytes in the
  descriptor.

* - where this is the number of bytes yet to be transferred to/from
  RAM.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:16:25 +01:00
Russell King
50437bff7f dmaengine: split out virtual channel DMA support from sa11x0 driver
Split the virtual slave channel DMA support from the sa11x0 driver so
this code can be shared with other slave DMA engine drivers.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:21 +01:00
Russell King
d9d5454014 ARM: sa11x0: fix build errors from DMA engine API updates
The recent merge of the sa11x0 code into mainline had silent conflicts
with further development of the DMA engine API, leading to build errors
and warnings:

drivers/net/irda/sa1100_ir.c: In function 'sa1100_irda_dma_start':
drivers/net/irda/sa1100_ir.c:151: error: too few arguments to function 'chan->device->device_prep_slave_sg'
drivers/dma/sa11x0-dma.c: In function 'sa11x0_dma_probe':
drivers/dma/sa11x0-dma.c:950: warning: assignment from incompatible pointer type

Fix these.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-03-30 11:46:20 +01:00
Russell King
6365bead25 DMA: sa11x0: add SA-11x0 DMA driver
Add support for the SA-11x0 DMA driver, which replaces the private
API version in arch/arm/mach-sa1100/dma.c.

We model this as a set of virtual DMA channels, one for each request
signal, and assign the virtual DMA channel to a physical DMA channel
when there is work to be done.  This allows DMA users to claim their
channels, and hold them while not in use, without affecting the
availability of the physical channels.

Another advantage over this approach, compared to the private version,
is that a channel can be reconfigured on the fly without having to
release and re-request it - which for the IrDA driver, allows us to
use DMA for SIR mode transmit without eating up three physical
channels.  As IrDA is half-duplex, we actually only need one physical
channel, and this architecture allows us to achieve that.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-03-07 11:32:21 +00:00