Re: [PATCH 26/26] usb: gadget: udc: s3c2410: replace usage of rc to check if a list element was found

[Krzysztof Kozlowski]

On 06/03/2022 18:50, Jakob Koschel wrote:
> To move the list iterator variable into the list_for_each_entry_*()
> macro in the future it should be avoided to use the list iterator
> variable after the loop body.
> 
> To *never* use the list iterator variable after the loop it was
> concluded to use a separate iterator variable [1].
> 
> This removes the need to check the rc value to determine if the
> break/goto was hit and can be made more obvious
> by checking if the variable was set within the list traversal loop.
> 
> Link: https://lore.kernel.org/all/YhdfEIwI4EdtHdym@xxxxxxxxx/
> Signed-off-by: Jakob Koschel <jakobkoschel@xxxxxxxxx>
> ---
>  drivers/usb/gadget/udc/s3c2410_udc.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/s3c2410_udc.c b/drivers/usb/gadget/udc/s3c2410_udc.c
> index e3931da24277..fe6ecb0d16d1 100644
> --- a/drivers/usb/gadget/udc/s3c2410_udc.c
> +++ b/drivers/usb/gadget/udc/s3c2410_udc.c
> @@ -1265,7 +1265,7 @@ static int s3c2410_udc_dequeue(struct usb_ep *_ep, struct usb_request *_req)
>  	struct s3c2410_ep	*ep = to_s3c2410_ep(_ep);
>  	int			retval = -EINVAL;
>  	unsigned long		flags;
> -	struct s3c2410_request	*req = NULL;
> +	struct s3c2410_request	*req = NULL, *tmp;
>  
>  	dprintk(DEBUG_VERBOSE, "%s(%p,%p)\n", __func__, _ep, _req);
>  
> @@ -1277,16 +1277,17 @@ static int s3c2410_udc_dequeue(struct usb_ep *_ep, struct usb_request *_req)
>  
>  	local_irq_save(flags);
>  
> -	list_for_each_entry(req, &ep->queue, queue) {
> -		if (&req->req == _req) {
> -			list_del_init(&req->queue);
> +	list_for_each_entry(tmp, &ep->queue, queue) {
> +		if (&tmp->req == _req) {
> +			list_del_init(&tmp->queue);
>  			_req->status = -ECONNRESET;
> +			req = tmp;
>  			retval = 0;
>  			break;
>  		}
>  	}
>  
> -	if (retval == 0) {
> +	if (req) {

I saw comments from Greg about it, so please keep similar approach here
as in patch 25. I propose to keep retval.

With retval restored:
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>

Best regards,
Krzysztof