Commit Graph

9 Commits

Author SHA1 Message Date
Alex Smith
ae9c02b421 dmaengine: jz4780: Kill tasklets before unregistering the device
Tasklets may have been scheduled as a result of an earlier interrupt
that could still be running. Kill them before unregistering the
device.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-18 22:28:50 +05:30
Alex Smith
d509a83cea dmaengine: jz4780: Don't use devm_*_irq() functions
We must explicitly free the IRQ before the device is unregistered in
case any device interrupt still occurs, so there's no point in using
the managed variations of the IRQ functions. Change to the regular
versions.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-18 22:28:50 +05:30
Alex Smith
026fd406c8 dmaengine: jz4780: Ensure channel is on correct controller in filter
When scanning for a free DMA channel, the filter function should ensure
that the channel is on the controller that it was requested to be on in
the DT.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-18 22:28:49 +05:30
Alex Smith
d3273e10ad dmaengine: jz4780: Use dma_get_slave_channel when requesting a specific channel
When the DT requests a specific channel to use it is not necesssary
to scan through all DMA channels in the system. Just return the
requested channel using dma_get_slave_channel().

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-18 22:28:49 +05:30
Alex Smith
839896ef3f dmaengine: jz4780: Fix error handling/signedness issues
There are a some signedness bugs such as testing for < 0 on unsigned
return values. Additionally there are some cases where functions which
should return NULL on error actually return a PTR_ERR value which can
result in oopses on error. Fix these issues.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-18 22:28:49 +05:30
Alex Smith
dc578f314e dmaengine: jz4780: Fall back on smaller transfer sizes where necessary
For some reason the controller does not support 8 byte transfers (but
does support all other powers of 2 up to 128). In this case fall back
to 4 bytes. In addition, fall back to 128 bytes when any larger power
of 2 would be possible within the alignment constraints, as this is
the maximum supported.

It makes no sense to outright reject 8 or >128 bytes just because the
alignment constraints make those the maximum possible size given the
parameters for the transaction. For instance, this can result in a DMA
from/to an 8 byte aligned address failing.

It is perfectly safe to fall back to smaller transfer sizes, the only
consequence is reduced transfer efficiency, which is far better than
not allowing the transfer at all.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-18 22:28:49 +05:30
Alex Smith
46fa516869 dmaengine: jz4780: Fix up dmaengine API function prototypes
Several function prototypes did not match the dmaengine API they were
implementing, resulting in build warnings. Correct these.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-18 22:28:49 +05:30
Maxime Ripard
77a68e56aa dmaengine: Add an enum for the dmaengine alignment constraints
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>
2015-08-05 10:53:52 +05:30
Alex Smith
d894fc6046 dmaengine: jz4780: add driver for the Ingenic JZ4780 DMA controller
This patch adds a driver for the DMA controller found in the Ingenic
JZ4780.

It currently does not implement any support for the programmable firmware
feature of the controller - this is not necessary for most uses. It also
does not take priority into account when allocating channels, it just
allocates the first available channel. This can be implemented later.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
[Updated for dmaengine api changes, Add residue support, couple of minor fixes]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-04-01 08:43:49 +05:30