[PATCH v2 01/10] dmaengine: bcm2835: Allow reusable descriptors

[Lukas Wunner <lukas@xxxxxxxxx>]

The DMA engine API requires DMA drivers to explicitly allow that
descriptors are prepared once and reused multiple times. Only a
single driver makes use of this functionality so far (pxa_dma.c,
to speed up pxa_camera.c).

We're about to add another use case for reusable descriptors in
the BCM2835 SPI driver, so allow that in the BCM2835 DMA driver.

Tested-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Tested-by: Noralf Trønnes <noralf@xxxxxxxxxxx>
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
Acked-by: Vinod Koul <vkoul@xxxxxxxxxx>
Acked-by: Stefan Wahren <wahrenst@xxxxxxx>
Acked-by: Martin Sperl <kernel@xxxxxxxxxxxxxxxx>
Cc: Florian Kauer <florian.kauer@xxxxxxxx>
Cc: Robert Jarzmik <robert.jarzmik@xxxxxxx>
---
 drivers/dma/bcm2835-dma.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c
index 8101ff2f05c1..523c507ad69e 100644
--- a/drivers/dma/bcm2835-dma.c
+++ b/drivers/dma/bcm2835-dma.c
@@ -907,6 +907,7 @@ static int bcm2835_dma_probe(struct platform_device *pdev)
 	od->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) |
 			      BIT(DMA_MEM_TO_MEM);
 	od->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+	od->ddev.descriptor_reuse = true;
 	od->ddev.dev = &pdev->dev;
 	INIT_LIST_HEAD(&od->ddev.channels);
 
-- 
2.23.0