dmaengine: stm32-dmamux: set dmamux channel id in dma features bitfield
authorAmelie Delaunay <amelie.delaunay@foss.st.com>
Mon, 29 Aug 2022 15:46:44 +0000 (17:46 +0200)
committerVinod Koul <vkoul@kernel.org>
Sun, 4 Sep 2022 17:18:02 +0000 (22:48 +0530)
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@foss.st.com>
Link: https://lore.kernel.org/r/20220829154646.29867-5-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
drivers/dma/stm32-dmamux.c

index eee0c5a..b431f9d 100644 (file)
@@ -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;