[PATCH 5.15 729/917] dmaengine: stm32-dma: fix stm32_dma_get_max_width

From: Greg Kroah-Hartman
Date: Mon Nov 15 2021 - 19:35:12 EST


From: Amelie Delaunay <amelie.delaunay@xxxxxxxxxxx>

[ Upstream commit b20fd5fa310cbf7ec367f263a34382a24c4cee73 ]

buf_addr parameter of stm32_dma_set_xfer_param function is a dma_addr_t.
We only need to check the remainder of buf_addr/max_width, so, no need to
use do_div and extra u64 addr. Use '%' instead.

Fixes: e0ebdbdcb42a ("dmaengine: stm32-dma: take address into account when computing max width")
Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20211011094259.315023-3-amelie.delaunay@xxxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/stm32-dma.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index 9063c727962ed..fdda916555ec5 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -270,7 +270,6 @@ static enum dma_slave_buswidth stm32_dma_get_max_width(u32 buf_len,
u32 threshold)
{
enum dma_slave_buswidth max_width;
- u64 addr = buf_addr;

if (threshold == STM32_DMA_FIFO_THRESHOLD_FULL)
max_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
@@ -281,7 +280,7 @@ static enum dma_slave_buswidth stm32_dma_get_max_width(u32 buf_len,
max_width > DMA_SLAVE_BUSWIDTH_1_BYTE)
max_width = max_width >> 1;

- if (do_div(addr, max_width))
+ if (buf_addr % max_width)
max_width = DMA_SLAVE_BUSWIDTH_1_BYTE;

return max_width;
--
2.33.0