Commit 4f910c03 authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Vinod Koul
Browse files

dmaengine: of-dma: Add support for optional router configuration callback 



Additional configuration for the DMA event router might be needed for a
channel which can not be done during device_alloc_chan_resources callback
since the router information is not yet present for the drivers.

If there is a need for additional configuration for the channel if DMA
router is in use, then the driver can implement the device_router_config
callback.

Signed-off-by: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20201208090440.31792-8-peter.ujfalusi@ti.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent d553e2ab

drivers/dma/of-dma.c

+10 −0
Original line number Diff line number Diff line
@@ -75,8 +75,18 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, 
		ofdma->dma_router->route_free(ofdma->dma_router->dev,

					      route_data);

	} else {

		int ret = 0;



		chan->router = ofdma->dma_router;

		chan->route_data = route_data;



		if (chan->device->device_router_config)

			ret = chan->device->device_router_config(chan);



		if (ret) {

			dma_release_channel(chan);

			chan = ERR_PTR(ret);

		}

	}



	/*

include/linux/dmaengine.h

+2 −0
Original line number Diff line number Diff line
@@ -805,6 +805,7 @@ struct dma_filter { 
 *	by tx_status

 * @device_alloc_chan_resources: allocate resources and return the

 *	number of allocated descriptors

 * @device_router_config: optional callback for DMA router configuration

 * @device_free_chan_resources: release DMA channel's resources

 * @device_prep_dma_memcpy: prepares a memcpy operation

 * @device_prep_dma_xor: prepares a xor operation
@@ -879,6 +880,7 @@ struct dma_device { 
	enum dma_residue_granularity residue_granularity;



	int (*device_alloc_chan_resources)(struct dma_chan *chan);

	int (*device_router_config)(struct dma_chan *chan);

	void (*device_free_chan_resources)(struct dma_chan *chan);



	struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(

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