STM32 DMAMUX is used with STM32 DMA1 and DMA2: - DMAMUX channels 0 to 7 are connected to DMA1 channels 0 to 7 - DMAMUX channels 8 to 15 are connected to DMA2 channels 0 to 7 STM32 MDMA can be triggered by DMA1 and DMA2 channels transfer complete, and the "request line number" is the DMAMUX channel id (e.g. DMA2 channel 0 triggers MDMA with request line 8). To well configure MDMA, set DMAMUX channel id in DMA features bitfield, so that DMA can update struct dma_slave_config peripheral_config properly. Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxxxxxxx> --- No changes in v2. --- drivers/dma/stm32-dmamux.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c index eee0c5aa5fb5..b431f9da9206 100644 --- a/drivers/dma/stm32-dmamux.c +++ b/drivers/dma/stm32-dmamux.c @@ -147,7 +147,7 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec, mux->request = dma_spec->args[0]; /* craft DMA spec */ - dma_spec->args[3] = dma_spec->args[2]; + dma_spec->args[3] = dma_spec->args[2] | mux->chan_id << 16; dma_spec->args[2] = dma_spec->args[1]; dma_spec->args[1] = 0; dma_spec->args[0] = mux->chan_id - min; -- 2.25.1
