On 7/13/22 16:21, Amelie Delaunay wrote: [...]
diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c index adb25a11c70f..3916295fe154 100644 --- a/drivers/dma/stm32-dma.c +++ b/drivers/dma/stm32-dma.c @@ -142,6 +142,8 @@ #define STM32_DMA_DIRECT_MODE_GET(n) (((n) & STM32_DMA_DIRECT_MODE_MASK) >> 2) #define STM32_DMA_ALT_ACK_MODE_MASK BIT(4) #define STM32_DMA_ALT_ACK_MODE_GET(n) (((n) & STM32_DMA_ALT_ACK_MODE_MASK) >> 4) +#define STM32_DMA_MDMA_STREAM_ID_MASK GENMASK(19, 16) +#define STM32_DMA_MDMA_STREAM_ID_GET(n) (((n) & STM32_DMA_MDMA_STREAM_ID_MASK) >> 16)
Try FIELD_GET() from include/linux/bitfield.h [...]
@@ -1630,6 +1670,20 @@ static int stm32_dma_probe(struct platform_device *pdev) chan->id = i; chan->vchan.desc_free = stm32_dma_desc_free; vchan_init(&chan->vchan, dd); + + chan->mdma_config.ifcr = res->start; + chan->mdma_config.ifcr += (chan->id & 4) ? STM32_DMA_HIFCR : STM32_DMA_LIFCR; + + chan->mdma_config.tcf = STM32_DMA_TCI; + /* + * bit0 of chan->id represents the need to left shift by 6 + * bit1 of chan->id represents the need to extra left shift by 16 + * TCIF0, chan->id = b0000; TCIF4, chan->id = b0100: left shift by 0*6 + 0*16 + * TCIF1, chan->id = b0001; TCIF5, chan->id = b0101: left shift by 1*6 + 0*16 + * TCIF2, chan->id = b0010; TCIF6, chan->id = b0110: left shift by 0*6 + 1*16 + * TCIF3, chan->id = b0011; TCIF7, chan->id = b0111: left shift by 1*6 + 1*16 + */ + chan->mdma_config.tcf <<= (6 * (chan->id & 0x1) + 16 * ((chan->id & 0x2) >> 1));
Some sort of symbolic macros instead of open-coded constants could help readability here.
[...]
