Re: [PATCH] ath10k: fix the status check and wrong return

[Tang Bin <tangbin@xxxxxxxxxxxxxxxxxxxx>]

Hi Kalle：

在 2020/8/17 22:26, Kalle Valo 写道:
> > In the function ath10k_ahb_clock_init(), devm_clk_get() doesn't
> > return NULL. Thus use IS_ERR() and PTR_ERR() to validate
> > the returned value instead of IS_ERR_OR_NULL().
> Why? What's the benefit of this patch? Or what harm does
> IS_ERR_OR_NULL() create?

Thanks for you reply, the benefit of this patch is simplify the code, 
because in

this function, I don't think the situation of 'devm_clk_get() return 
NULL' exists.

So please think about it, thanks.


Tang Bin

> > Signed-off-by: Zhang Shengju <zhangshengju@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Tang Bin <tangbin@xxxxxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/net/wireless/ath/ath10k/ahb.c | 12 ++++++------
> >   1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/net/wireless/ath/ath10k/ahb.c b/drivers/net/wireless/ath/ath10k/ahb.c
> > index ed87bc00f..ea669af6a 100644
> > --- a/drivers/net/wireless/ath/ath10k/ahb.c
> > +++ b/drivers/net/wireless/ath/ath10k/ahb.c
> > @@ -87,24 +87,24 @@ static int ath10k_ahb_clock_init(struct ath10k *ar)
> >   	dev = &ar_ahb->pdev->dev;
> >   
> >   	ar_ahb->cmd_clk = devm_clk_get(dev, "wifi_wcss_cmd");
> > -	if (IS_ERR_OR_NULL(ar_ahb->cmd_clk)) {
> > +	if (IS_ERR(ar_ahb->cmd_clk)) {
> >   		ath10k_err(ar, "failed to get cmd clk: %ld\n",
> >   			   PTR_ERR(ar_ahb->cmd_clk));
> > -		return ar_ahb->cmd_clk ? PTR_ERR(ar_ahb->cmd_clk) : -ENODEV;
> > +		return PTR_ERR(ar_ahb->cmd_clk);
> >   	}
> devm_clk_get() can return NULL if CONFIG_HAVE_CLK is disabled:
>
> static inline struct clk *devm_clk_get(struct device *dev, const char *id)
> {
> 	return NULL;
> }