Re: [PATCH 2/2] i2c: lpi2c: Use cleanup helper for dma_async_tx_descriptor error handling

[Christophe JAILLET <christophe.jaillet@wanadoo.fr>]

Le 02/10/2025 à 21:49, Frank Li a écrit :
> Use the cleanup helper to simplify dma_async_tx_descriptor error handling.
> 
> No functional change.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>   drivers/i2c/busses/i2c-imx-lpi2c.c | 11 +++--------
>   1 file changed, 3 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
> index 03b5a7e8c361abe1d75fb4d31f9614bbc6387d93..b1d035ca8002e9648b67bfe4d674578373394710 100644
> --- a/drivers/i2c/busses/i2c-imx-lpi2c.c
> +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
> @@ -722,7 +722,7 @@ static void lpi2c_dma_callback(void *data)
>   
>   static int lpi2c_dma_rx_cmd_submit(struct lpi2c_imx_struct *lpi2c_imx)
>   {
> -	struct dma_async_tx_descriptor *rx_cmd_desc;
> +	struct dma_async_tx_descriptor *rx_cmd_desc __free(dma_async_tx_descriptor) = NULL;
>   	struct lpi2c_imx_dma *dma = lpi2c_imx->dma;
>   	struct dma_chan *txchan = dma->chan_tx;
>   	dma_cookie_t cookie;
> @@ -746,10 +746,11 @@ static int lpi2c_dma_rx_cmd_submit(struct lpi2c_imx_struct *lpi2c_imx)
>   	cookie = dmaengine_submit(rx_cmd_desc);
>   	if (dma_submit_error(cookie)) {
>   		dev_err(&lpi2c_imx->adapter.dev, "submitting DMA failed, use pio\n");
> -		goto submit_err_exit;
> +		return dma_submit_error(cookie);

I don't know if it matters or not, but this may change the returned 
value in this error handling path.

>   	}
>   
>   	dma_async_issue_pending(txchan);
> +	retain_and_null_ptr(rx_cmd_desc);
>   
>   	return 0;
>   
> @@ -757,12 +758,6 @@ static int lpi2c_dma_rx_cmd_submit(struct lpi2c_imx_struct *lpi2c_imx)
>   	dma_unmap_single(txchan->device->dev, dma->dma_tx_addr,
>   			 dma->rx_cmd_buf_len, DMA_TO_DEVICE);
>   	return -EINVAL;
> -
> -submit_err_exit:
> -	dma_unmap_single(txchan->device->dev, dma->dma_tx_addr,
> -			 dma->rx_cmd_buf_len, DMA_TO_DEVICE);

dma_unmap_single() is not needed anymore?

> -	dmaengine_desc_free(rx_cmd_desc);
> -	return -EINVAL;
>   }
>   
>   static int lpi2c_dma_submit(struct lpi2c_imx_struct *lpi2c_imx)
>