Re: [PATCH] USB: dwc3: add missing of_node_put()

[Patrice CHOTARD <patrice.chotard@st.com>]

Hi Wen

On 2/3/19 4:52 AM, wen yang wrote:
> The call to of_find_node_by_name returns a node pointer with refcount
> incremented thus it must be explicitly decremented here after the last
> usage.
> The of_find_device_by_node() takes a reference to the underlying device
> structure, we also should release that reference.
> This patch fixes those 2 issues.
> 
> Signed-off-by: Wen Yang <yellowriver2010@hotmail.com>
> Cc: Patrice Chotard <patrice.chotard@st.com>
> Cc: Felipe Balbi <balbi@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-usb@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  drivers/usb/dwc3/dwc3-st.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-st.c b/drivers/usb/dwc3/dwc3-st.c
> index 1608138..fdd90d2 100644
> --- a/drivers/usb/dwc3/dwc3-st.c
> +++ b/drivers/usb/dwc3/dwc3-st.c
> @@ -262,17 +262,18 @@ static int st_dwc3_probe(struct platform_device *pdev)
>  	ret = of_platform_populate(node, NULL, NULL, dev);
>  	if (ret) {
>  		dev_err(dev, "failed to add dwc3 core\n");
> -		goto undo_softreset;
> +		goto put_node;
>  	}
>  
>  	child_pdev = of_find_device_by_node(child);
>  	if (!child_pdev) {
>  		dev_err(dev, "failed to find dwc3 core device\n");
>  		ret = -ENODEV;
> -		goto undo_softreset;
> +		goto put_node;
>  	}
>  
>  	dwc3_data->dr_mode = usb_get_dr_mode(&child_pdev->dev);
> +	put_device(&child_pdev->dev);
>  
>  	/*
>  	 * Configure the USB port as device or host according to the static
> @@ -283,15 +284,18 @@ static int st_dwc3_probe(struct platform_device *pdev)
>  	ret = st_dwc3_drd_init(dwc3_data);
>  	if (ret) {
>  		dev_err(dev, "drd initialisation failed\n");
> -		goto undo_softreset;
> +		goto put_node;
>  	}
>  
>  	/* ST glue logic init */
>  	st_dwc3_init(dwc3_data);
>  
>  	platform_set_drvdata(pdev, dwc3_data);
> +	of_node_put(child);
>  	return 0;
>  
> +put_node:
> +	of_node_put(child);
>  undo_softreset:
>  	reset_control_assert(dwc3_data->rstc_rst);
>  undo_powerdown:
> 

Reviewed-by: Patrice Chotard <patrice.chotard@st.com>

Thanks