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| author |   Peter Ujfalusi <peter.ujfalusi@ti.com> | 2020-12-08 11:04:28 +0200 |
|---|---|---|
| committer |   Vinod Koul <vkoul@kernel.org> | 2020-12-11 21:20:08 +0530 |
| commit | ab650ef6d548153862119e1bf3bf267510707f48 (patch) | |
| tree | 9ec923ada712fb62c210df4e216bcb0369a7bada /include/linux/dmaengine.h | |
| parent | dmaengine: of-dma: Add support for optional router configuration callback (diff) | |
| download | linux-dev-ab650ef6d548153862119e1bf3bf267510707f48.tar.xz linux-dev-ab650ef6d548153862119e1bf3bf267510707f48.zip | |
dmaengine: Add support for per channel coherency handling
If the DMA device supports per channel coherency configuration (a channel
can be configured to have coherent or not coherent view) then a single
device (the DMA controller's device) can not be used for dma_api for all
channels as channels can have different coherency.
Introduce custom_dma_mapping flag for the dma_chan and a new helper to get
the device pointer to be used for dma_api for the given channel.
Client drivers should be updated to be able to support per channel
coherency by:
- dma_map_single(chan->device->dev, ptr, size, DMA_TO_DEVICE);
+ struct device *dma_dev = dmaengine_get_dma_device(chan);
+
+ dma_map_single(dma_dev, ptr, size, DMA_TO_DEVICE);
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20201208090440.31792-9-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'include/linux/dmaengine.h')
| -rw-r--r-- | include/linux/dmaengine.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index aed44888cad3..68130f5f599e 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -357,11 +357,14 @@ struct dma_chan { * @chan: driver channel device * @device: sysfs device * @dev_id: parent dma_device dev_id + * @chan_dma_dev: The channel is using custom/different dma-mapping + * compared to the parent dma_device */ struct dma_chan_dev { struct dma_chan *chan; struct device device; int dev_id; + bool chan_dma_dev; }; /** @@ -1618,4 +1621,13 @@ dmaengine_get_direction_text(enum dma_transfer_direction dir) return "invalid"; } } + +static inline struct device *dmaengine_get_dma_device(struct dma_chan *chan) +{ + if (chan->dev->chan_dma_dev) + return &chan->dev->device; + + return chan->device->dev; +} + #endif /* DMAENGINE_H */ |