linux-kernel - Re: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of counter variable k

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Message-ID: <20200224112735.GC3286@kadam>
Date:   Mon, 24 Feb 2020 14:27:35 +0300
From:   Dan Carpenter <dan.carpenter@...cle.com>
To:     Walter Harms <wharms@....de>
Cc:     Colin King <colin.king@...onical.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "devel@...verdev.osuosl.org" <devel@...verdev.osuosl.org>,
        "kernel-janitors@...r.kernel.org" <kernel-janitors@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of
 counter variable k

On Mon, Feb 24, 2020 at 11:07:55AM +0000, Walter Harms wrote:
> diff --git a/drivers/staging/rtl8723bs/core/rtw_efuse.c b/drivers/staging/rtl8723bs/core/rtw_efuse.c
> index 3b8848182221..bdb6ff8aab7d 100644
> --- a/drivers/staging/rtl8723bs/core/rtw_efuse.c
> +++ b/drivers/staging/rtl8723bs/core/rtw_efuse.c
> @@ -244,10 +244,8 @@ u16        Address)
>                 while (!(Bytetemp & 0x80)) {
>                         Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
>                         k++;
> -                       if (k == 1000) {
> -                               k = 0;
> +                       if (k == 1000)
>                                 break;
> -                       }
> 
> IMHO this is confusing to read, i suggest:
> 
>  for(k=0;k<1000;k++) {
>       Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
>       if ( Bytetemp & 0x80 )
>                break;
>       }
> 

The problem with the original code is that the variable is named "k"
instead of "retry".  It should be:

	do {
		Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
	} while (!(Bytetemp & 0x80)) && ++retry < 1000);


>  NTL is am wondering what will happen if k==1000
>  and Bytetemp is still invalid. Will rtw_read8() fail or
>  simply return invalid data ?

Yeah.  That was my thought reviewing this patch as well.

It should probably return 0xff on failure.

	if (retry >= 1000)
		return 0xff;

regards,
dan carpenter