Subject: [PATCH V2] tty: serial: fsl_lpuart: use the sg count from dma_map_sg

Ignore this patch. Keep v1.

Thanks, Peng.

From: Peng Fan peng.fan@nxp.com

The dmaengine_prep_slave_sg needs to use sg count returned by dma_map_sg, not use sport->dma_tx_nents, because the return value of dma_map_sg is not always same with "nents".

When enabling iommu for lpuart + edma, iommu framework may concatenate two sgs into one.

Fixes: 6250cc30c4c4e ("tty: serial: fsl_lpuart: Use scatter/gather DMA for Tx") Cc: stable@vger.kernel.org Signed-off-by: Peng Fan peng.fan@nxp.com

---

V2: Assign ret to sport->dma_tx_nents, then we no need to fix dma_unmap_sg Hi Greg, I saw v1 patch merged to tty-next, please help to replace with V2 if this is ok for you, or you need I have a follow up fix for v1.

drivers/tty/serial/fsl_lpuart.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 3e17bb8a0b16..ec5ea098669e 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -436,6 +436,7 @@ static void lpuart_dma_tx(struct lpuart_port *sport) return; }

• sport->dma_tx_nents = ret; sport->dma_tx_desc = dmaengine_prep_slave_sg(sport->dma_tx_chan,

sgl, sport->dma_tx_nents, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT); -- 2.16.4