From ab650ef6d548153862119e1bf3bf267510707f48 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Tue, 8 Dec 2020 11:04:28 +0200 Subject: 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 Link: https://lore.kernel.org/r/20201208090440.31792-9-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/linux/dmaengine.h') 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 */ -- cgit v1.2.3-59-g8ed1b