linux-toradex.git/drivers/dma/dw-axi-dmac, branch v6.15

dmaengine: Switch back to struct platform_driver::remove()

2024-10-14T18:20:34+00:00

After commit 0edb555a65d1 ("platform: Make platform_driver::remove()
return void") .remove() is (again) the right callback to implement for
platform drivers.

Convert all platform drivers below drivers/dma after the previous
conversion commits apart from the wireless drivers to use .remove(),
with the eventual goal to drop struct platform_driver::remove_new(). As
.remove() and .remove_new() have the same prototypes, conversion is done
by just changing the structure member name in the driver initializer.

Signed-off-by: Uwe Kleine-König 
Link: https://lore.kernel.org/r/20241004062227.187726-2-u.kleine-koenig@baylibre.com
Signed-off-by: Vinod Koul

dma: dw-axi-dmac: support per channel interrupt

2024-04-07T11:48:14+00:00

Hardware might not support a single combined interrupt that covers all
channels. In that case we have to deal with interrupt per channel. Add
support for that configuration.

Signed-off-by: Baruch Siach 
Link: https://lore.kernel.org/r/ebab52e886ef1adc3c40e636aeb1ba3adfe2e578.1711453387.git.baruchs-c@neureality.ai
Signed-off-by: Vinod Koul

Avoid hw_desc array overrun in dw-axi-dmac

2024-04-07T11:45:24+00:00

I have a use case where nr_buffers = 3 and in which each descriptor is composed by 3
segments, resulting in the DMA channel descs_allocated to be 9. Since axi_desc_put()
handles the hw_desc considering the descs_allocated, this scenario would result in a
kernel panic (hw_desc array will be overrun).

To fix this, the proposal is to add a new member to the axi_dma_desc structure,
where we keep the number of allocated hw_descs (axi_desc_alloc()) and use it in
axi_desc_put() to handle the hw_desc array correctly.

Additionally I propose to remove the axi_chan_start_first_queued() call after completing
the transfer, since it was identified that unbalance can occur (started descriptors can
be interrupted and transfer ignored due to DMA channel not being enabled).

Signed-off-by: Joao Pinto 
Link: https://lore.kernel.org/r/1711536564-12919-1-git-send-email-jpinto@synopsys.com
Signed-off-by: Vinod Koul

dmaengine: dw-axi-dmac: Add support for StarFive JH8100 DMA

2024-04-07T11:41:12+00:00

JH8100 requires reset operation only in device probe.

Signed-off-by: Tan Chun Hau 
Link: https://lore.kernel.org/r/20240327025126.229475-3-chunhau.tan@starfivetech.com
Signed-off-by: Vinod Koul

dmaengine: dw-axi-dmac: Add support DMAX_NUM_CHANNELS > 16

2023-10-16T11:08:10+00:00

Added support for DMA controller with more than 16 channels.

Signed-off-by: Sergey Khimich 
Link: https://lore.kernel.org/r/20231010101450.2949126-2-serghox@gmail.com
Signed-off-by: Vinod Koul

dmaengine: dw-axi-dmac: dw-axi-dmac-platform: Convert to platform remove callback returning void

2023-09-28T07:40:47+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König 
Link: https://lore.kernel.org/r/20230919133207.1400430-11-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul

dmaengine: Explicitly include correct DT includes

2023-08-01T18:21:27+00:00

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring 
Link: https://lore.kernel.org/r/20230718143138.1066177-1-robh@kernel.org
Signed-off-by: Vinod Koul

dmaengine: dw-axi-dmac: Don't set chancnt

2023-05-24T06:54:32+00:00

The dma framework will calculate the dma channels chancnt, setting it
ourself is wrong.

Signed-off-by: Jisheng Zhang 
Link: https://lore.kernel.org/r/20230521100252.3197-2-jszhang@kernel.org
Signed-off-by: Vinod Koul

dmaengine: dw-axi-dmac: Increase polling time to DMA transmission completion status

2023-04-12T17:48:43+00:00

The bit DMAC_CHEN[0] is automatically cleared by hardware to disable the
channel after the last AMBA transfer of the DMA transfer to the
destination has completed. Software can therefore poll this bit to
determine when this channel is free for a new DMA transfer.
This time requires at least 40 milliseconds on JH7110 SoC, otherwise an
error message 'failed to stop' will be reported.

Signed-off-by: Walker Chen 
Link: https://lore.kernel.org/r/20230322094820.24738-4-walker.chen@starfivetech.com
Signed-off-by: Vinod Koul

dmaengine: dw-axi-dmac: Add support for StarFive JH7110 DMA

2023-04-12T17:48:43+00:00

Add DMA reset operation in device probe and use different configuration
on CH_CFG registers according to match data. Update all uses of
of_device_is_compatible with of_device_get_match_data.

Signed-off-by: Walker Chen 
Reviewed-by: Emil Renner Berthing 
Link: https://lore.kernel.org/r/20230322094820.24738-3-walker.chen@starfivetech.com
Signed-off-by: Vinod Koul