Re: [PATCH] staging: rtl8723au: Fix sparse warnings

[Larry Finger <Larry.Finger@lwfinger.net>]

On 12/11/2014 04:23 PM, Krzysztof Konopko wrote:
> Some struct fields in wifi.h are meant to be __le16 bu were declared as
> unsigned short.  This was reported by sparse:
>
>    rtw_wlan_util.c:538:24: warning: cast to restricted __le16
>    rtw_wlan_util.c:1544:29: warning: cast to restricted __le16
>    rtw_wlan_util.c:1546:25: warning: cast to restricted __le16
>
> This patch changes declared types of the struct fields involved.
>
> Signed-off-by: Krzysztof Konopko <kris@konagma.com>
> ---
>   drivers/staging/rtl8723au/include/wifi.h | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/staging/rtl8723au/include/wifi.h b/drivers/staging/rtl8723au/include/wifi.h
> index fd3da3b..8a2adc5 100644
> --- a/drivers/staging/rtl8723au/include/wifi.h
> +++ b/drivers/staging/rtl8723au/include/wifi.h
> @@ -28,7 +28,7 @@
>   struct AC_param {
>   	unsigned char		ACI_AIFSN;
>   	unsigned char		CW;
> -	unsigned short	TXOP_limit;
> +	__le16			TXOP_limit;
>   }  __packed;
>
>   struct WMM_para_element {
> @@ -39,9 +39,9 @@ struct WMM_para_element {
>
>   struct ADDBA_request {
>   	unsigned char		dialog_token;
> -	unsigned short	BA_para_set;
> +	__le16		BA_para_set;
>   	unsigned short	BA_timeout_value;
> -	unsigned short	BA_starting_seqctrl;
> +	__le16		BA_starting_seqctrl;
>   }  __packed;

This fix may make the sparse warnings go away, but I think it introduces new 
bugs. In particular, did you test on big-endian hardware after you made this 
change? I recently found that the driver for RTL8188EU needed to have 
BA_para_set to unsigned short, and the endianess warnings needed to be fixed in 
the code. Then it would work on my PowerBook G4 with a PPC processor.

In RTL8188EU, both BA_starting_seqctrl and TXOP_limit are unsigned short.

Larry