[PATCH v3] pch_uart: Fix dma_sync_sg_for_device() nents value

[PATCH v3] pch_uart: Fix dma_sync_sg_for_device() nents value

[Thomas Fourier]

The dma_sync_sg_for_device() functions should be called with the same
nents as the dma_map_sg(), not the value the map function returned
according to the documentation in Documentation/core-api/dma-api.rst:450:
	With the sync_sg API, all the parameters must be the same
	as those passed into the sg mapping API.


Fixes: da3564ee027e ("pch_uart: add multi-scatter processing")
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
---

v2 -> v3:

- Adding reference to documentation

v1 -> v2:

- Fixing value

 drivers/tty/serial/pch_uart.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index 508e8c6f01d4..884fefbfd5a1 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -954,7 +954,7 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv)
 			__func__);
 		return 0;
 	}
-	dma_sync_sg_for_device(port->dev, priv->sg_tx_p, nent, DMA_TO_DEVICE);
+	dma_sync_sg_for_device(port->dev, priv->sg_tx_p, num, DMA_TO_DEVICE);
 	priv->desc_tx = desc;
 	desc->callback = pch_dma_tx_complete;
 	desc->callback_param = priv;
-- 
2.43.0

Re: [PATCH v3] pch_uart: Fix dma_sync_sg_for_device() nents value

[Andy Shevchenko]

On Tue, Jul 01, 2025 at 01:34:52PM +0200, Thomas Fourier wrote:
> The dma_sync_sg_for_device() functions should be called with the same
> nents as the dma_map_sg(), not the value the map function returned
> according to the documentation in Documentation/core-api/dma-api.rst:450:
> 	With the sync_sg API, all the parameters must be the same
> 	as those passed into the sg mapping API.

Good enough to me,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3] pch_uart: Fix dma_sync_sg_for_device() nents value

[Greg KH]

On Tue, Jul 01, 2025 at 01:34:52PM +0200, Thomas Fourier wrote:
> The dma_sync_sg_for_device() functions should be called with the same
> nents as the dma_map_sg(), not the value the map function returned
> according to the documentation in Documentation/core-api/dma-api.rst:450:
> 	With the sync_sg API, all the parameters must be the same
> 	as those passed into the sg mapping API.
> 
> 
> Fixes: da3564ee027e ("pch_uart: add multi-scatter processing")
> Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
> ---
> 
> v2 -> v3:
> 
> - Adding reference to documentation
> 
> v1 -> v2:
> 
> - Fixing value
> 
>  drivers/tty/serial/pch_uart.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
> index 508e8c6f01d4..884fefbfd5a1 100644
> --- a/drivers/tty/serial/pch_uart.c
> +++ b/drivers/tty/serial/pch_uart.c
> @@ -954,7 +954,7 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv)
>  			__func__);
>  		return 0;
>  	}
> -	dma_sync_sg_for_device(port->dev, priv->sg_tx_p, nent, DMA_TO_DEVICE);
> +	dma_sync_sg_for_device(port->dev, priv->sg_tx_p, num, DMA_TO_DEVICE);
>  	priv->desc_tx = desc;
>  	desc->callback = pch_dma_tx_complete;
>  	desc->callback_param = priv;
> -- 
> 2.43.0
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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