Re: [PATCH 2/15] drivers/usb/chipidea/core.c: adjust duplicate test

From: Peter Chen
Date: Mon Jan 21 2013 - 18:44:45 EST


On Mon, Jan 21, 2013 at 02:02:46PM +0100, Julia Lawall wrote:
> From: Julia Lawall <Julia.Lawall@xxxxxxx>
>
> Delete successive tests to the same location. In this case res has already
> been tested for being NULL, and calling devm_request_and_ioremap will not
> make it NULL. On the other hand, devm_request_and_ioremap can return NULL
> on failure.
>
> A simplified version of the semantic match that finds this problem is as
> follows: (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @s exists@
> local idexpression y;
> expression x,e;
> @@
>
> *if ( \(x == NULL\|IS_ERR(x)\|y != 0\) )
> { ... when forall
> return ...; }
> ... when != \(y = e\|y += e\|y -= e\|y |= e\|y &= e\|y++\|y--\|&y\)
> when != \(XT_GETPAGE(...,y)\|WMI_CMD_BUF(...)\)
> *if ( \(x == NULL\|IS_ERR(x)\|y != 0\) )
> { ... when forall
> return ...; }
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>
>
> ---
> This code could be improved in other ways. The previous NULL test on res
> is not needed, and the dev_err in the error-handling code for the call to
> devm_request_and_ioremap is redundant with respect to the logging already
> done by devm_request_and_ioremap. But these should probably be done
> separately.
>
> drivers/usb/chipidea/core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
> index aebf695..57cae1f 100644
> --- a/drivers/usb/chipidea/core.c
> +++ b/drivers/usb/chipidea/core.c
> @@ -411,7 +411,7 @@ static int ci_hdrc_probe(struct platform_device *pdev)
> }
>
> base = devm_request_and_ioremap(dev, res);
> - if (!res) {
> + if (!base) {
> dev_err(dev, "can't request and ioremap resource\n");
> return -ENOMEM;
> }
>
Tested-and-reviewed-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>

--

Best Regards,
Peter Chen

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