* [PATCH] tty: serial: fsl_lpuart: use dmaengine_get_dma_device() for DMA mapping
@ 2026-09-16 15:27 Peng Fan (OSS)
2026-09-16 19:22 ` Frank Li
0 siblings, 1 reply; 2+ messages in thread
From: Peng Fan (OSS) @ 2026-09-16 15:27 UTC (permalink / raw)
To: Greg Kroah-Hartman, Jiri Slaby, Frank Li
Cc: Sherry Sun, imx, linux-kernel, linux-serial, Peng Fan
From: Peng Fan <peng.fan@nxp.com>
Replace all chan->device->dev references with
dmaengine_get_dma_device(chan) so that DMA mapping goes through the
correct device when the DMA controller has per-channel IOMMU domains
(chan_dma_dev=true). Without this, DMA map/unmap/sync bypasses the
IOMMU context configured by the eDMA driver.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
drivers/tty/serial/fsl_lpuart.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index b7919c05f0fb8..c8575c9652035 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -491,7 +491,7 @@ static void lpuart_dma_tx(struct lpuart_port *sport)
sport->dma_tx_nents = kfifo_dma_out_prepare(&tport->xmit_fifo, sgl,
ARRAY_SIZE(sport->tx_sgl), sport->dma_tx_bytes);
- ret = dma_map_sg(chan->device->dev, sgl, sport->dma_tx_nents,
+ ret = dma_map_sg(dmaengine_get_dma_device(chan), sgl, sport->dma_tx_nents,
DMA_TO_DEVICE);
if (!ret) {
dev_err(dev, "DMA mapping error for TX.\n");
@@ -502,7 +502,7 @@ static void lpuart_dma_tx(struct lpuart_port *sport)
ret, DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT);
if (!sport->dma_tx_desc) {
- dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
+ dma_unmap_sg(dmaengine_get_dma_device(chan), sgl, sport->dma_tx_nents,
DMA_TO_DEVICE);
dev_err(dev, "Cannot prepare TX slave DMA!\n");
return;
@@ -535,7 +535,7 @@ static void lpuart_dma_tx_complete(void *arg)
return;
}
- dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
+ dma_unmap_sg(dmaengine_get_dma_device(chan), sgl, sport->dma_tx_nents,
DMA_TO_DEVICE);
uart_xmit_advance(&sport->port, sport->dma_tx_bytes);
@@ -606,7 +606,7 @@ static void lpuart_flush_buffer(struct uart_port *port)
if (sport->lpuart_dma_tx_use) {
if (sport->dma_tx_in_progress) {
- dma_unmap_sg(chan->device->dev, &sport->tx_sgl[0],
+ dma_unmap_sg(dmaengine_get_dma_device(chan), &sport->tx_sgl[0],
sport->dma_tx_nents, DMA_TO_DEVICE);
sport->dma_tx_in_progress = false;
}
@@ -1176,7 +1176,7 @@ static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
}
/* CPU claims ownership of RX DMA buffer */
- dma_sync_sg_for_cpu(chan->device->dev, &sport->rx_sgl, 1,
+ dma_sync_sg_for_cpu(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1,
DMA_FROM_DEVICE);
/*
@@ -1237,7 +1237,7 @@ static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
sport->last_residue = state.residue;
exit:
- dma_sync_sg_for_device(chan->device->dev, &sport->rx_sgl, 1,
+ dma_sync_sg_for_device(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1,
DMA_FROM_DEVICE);
uart_port_unlock_irqrestore(&sport->port, flags);
@@ -1374,7 +1374,7 @@ static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
return -ENOMEM;
sg_init_one(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
- nent = dma_map_sg(chan->device->dev, &sport->rx_sgl, 1,
+ nent = dma_map_sg(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1,
DMA_FROM_DEVICE);
if (!nent) {
@@ -1430,7 +1430,7 @@ static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
return 0;
err_unmap_sg:
- dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
+ dma_unmap_sg(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1, DMA_FROM_DEVICE);
err_free_buf:
kfree(ring->buf);
ring->buf = NULL;
@@ -1447,7 +1447,7 @@ static void lpuart_dma_rx_free(struct uart_port *port)
if (!sport->dma_idle_int)
timer_delete_sync(&sport->lpuart_timer);
- dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
+ dma_unmap_sg(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1, DMA_FROM_DEVICE);
kfree(sport->rx_ring.buf);
sport->rx_ring.tail = 0;
sport->rx_ring.head = 0;
---
base-commit: e6e35979777d646fe3c7c94dca7dd32fb25d45f4
change-id: 20260916-lpuart-dma-9923b7b2e1da
Best regards,
--
Peng Fan <peng.fan@nxp.com>
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: [PATCH] tty: serial: fsl_lpuart: use dmaengine_get_dma_device() for DMA mapping
2026-09-16 15:27 [PATCH] tty: serial: fsl_lpuart: use dmaengine_get_dma_device() for DMA mapping Peng Fan (OSS)
@ 2026-09-16 19:22 ` Frank Li
0 siblings, 0 replies; 2+ messages in thread
From: Frank Li @ 2026-09-16 19:22 UTC (permalink / raw)
To: Peng Fan (OSS)
Cc: Greg Kroah-Hartman, Jiri Slaby, Frank Li, Sherry Sun, imx,
linux-kernel, linux-serial, Peng Fan
On Wed, Sep 16, 2026 at 11:27:30PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@nxp.com>
>
> Replace all chan->device->dev references with
> dmaengine_get_dma_device(chan) so that DMA mapping goes through the
> correct device when the DMA controller has per-channel IOMMU domains
> (chan_dma_dev=true). Without this, DMA map/unmap/sync bypasses the
> IOMMU context configured by the eDMA driver.
>
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---
Reviewed-by: Frank Li <Frank.Li@nxp.com>
> drivers/tty/serial/fsl_lpuart.c | 18 +++++++++---------
> 1 file changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
> index b7919c05f0fb8..c8575c9652035 100644
> --- a/drivers/tty/serial/fsl_lpuart.c
> +++ b/drivers/tty/serial/fsl_lpuart.c
> @@ -491,7 +491,7 @@ static void lpuart_dma_tx(struct lpuart_port *sport)
> sport->dma_tx_nents = kfifo_dma_out_prepare(&tport->xmit_fifo, sgl,
> ARRAY_SIZE(sport->tx_sgl), sport->dma_tx_bytes);
>
> - ret = dma_map_sg(chan->device->dev, sgl, sport->dma_tx_nents,
> + ret = dma_map_sg(dmaengine_get_dma_device(chan), sgl, sport->dma_tx_nents,
> DMA_TO_DEVICE);
> if (!ret) {
> dev_err(dev, "DMA mapping error for TX.\n");
> @@ -502,7 +502,7 @@ static void lpuart_dma_tx(struct lpuart_port *sport)
> ret, DMA_MEM_TO_DEV,
> DMA_PREP_INTERRUPT);
> if (!sport->dma_tx_desc) {
> - dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
> + dma_unmap_sg(dmaengine_get_dma_device(chan), sgl, sport->dma_tx_nents,
> DMA_TO_DEVICE);
> dev_err(dev, "Cannot prepare TX slave DMA!\n");
> return;
> @@ -535,7 +535,7 @@ static void lpuart_dma_tx_complete(void *arg)
> return;
> }
>
> - dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
> + dma_unmap_sg(dmaengine_get_dma_device(chan), sgl, sport->dma_tx_nents,
> DMA_TO_DEVICE);
>
> uart_xmit_advance(&sport->port, sport->dma_tx_bytes);
> @@ -606,7 +606,7 @@ static void lpuart_flush_buffer(struct uart_port *port)
>
> if (sport->lpuart_dma_tx_use) {
> if (sport->dma_tx_in_progress) {
> - dma_unmap_sg(chan->device->dev, &sport->tx_sgl[0],
> + dma_unmap_sg(dmaengine_get_dma_device(chan), &sport->tx_sgl[0],
> sport->dma_tx_nents, DMA_TO_DEVICE);
> sport->dma_tx_in_progress = false;
> }
> @@ -1176,7 +1176,7 @@ static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
> }
>
> /* CPU claims ownership of RX DMA buffer */
> - dma_sync_sg_for_cpu(chan->device->dev, &sport->rx_sgl, 1,
> + dma_sync_sg_for_cpu(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1,
> DMA_FROM_DEVICE);
>
> /*
> @@ -1237,7 +1237,7 @@ static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
> sport->last_residue = state.residue;
>
> exit:
> - dma_sync_sg_for_device(chan->device->dev, &sport->rx_sgl, 1,
> + dma_sync_sg_for_device(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1,
> DMA_FROM_DEVICE);
>
> uart_port_unlock_irqrestore(&sport->port, flags);
> @@ -1374,7 +1374,7 @@ static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
> return -ENOMEM;
>
> sg_init_one(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
> - nent = dma_map_sg(chan->device->dev, &sport->rx_sgl, 1,
> + nent = dma_map_sg(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1,
> DMA_FROM_DEVICE);
>
> if (!nent) {
> @@ -1430,7 +1430,7 @@ static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
> return 0;
>
> err_unmap_sg:
> - dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
> + dma_unmap_sg(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1, DMA_FROM_DEVICE);
> err_free_buf:
> kfree(ring->buf);
> ring->buf = NULL;
> @@ -1447,7 +1447,7 @@ static void lpuart_dma_rx_free(struct uart_port *port)
> if (!sport->dma_idle_int)
> timer_delete_sync(&sport->lpuart_timer);
>
> - dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
> + dma_unmap_sg(dmaengine_get_dma_device(chan), &sport->rx_sgl, 1, DMA_FROM_DEVICE);
> kfree(sport->rx_ring.buf);
> sport->rx_ring.tail = 0;
> sport->rx_ring.head = 0;
>
> ---
> base-commit: e6e35979777d646fe3c7c94dca7dd32fb25d45f4
> change-id: 20260916-lpuart-dma-9923b7b2e1da
>
> Best regards,
> --
> Peng Fan <peng.fan@nxp.com>
>
>
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2026-09-16 19:23 UTC | newest]
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2026-09-16 19:22 ` Frank Li
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