[PATCH 5.14 696/849] dmaengine: stm32-dma: fix stm32_dma_get_max_width

Greg Kroah-Hartman
2021-11-15T23:16:07Z

From: Amelie Delaunay <amelie.delaunay@foss.st.com>

[ 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@foss.st.com>
Link: https://lore.kernel.org/r/20211011094259.315023-3-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 7dd1d3d0bf063..a5dab5510e625 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -268,7 +268,6 @@ 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;
@@ -279,7 +278,7 @@ 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