Re: [PATCH v2] char: mwave: smapi: Fix signedness of SmapiOK variable

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Apr 17, 2025 at 02:40:18PM +0530, Purva Yeshi wrote:
> Smatch warning:
> drivers/char/mwave/smapi.c:69 smapi_request() warn:
> assigning (-5) to unsigned variable 'usSmapiOK'
> 
> Fix Smatch warning caused by assigning -EIO to an unsigned short.
> 
> Smatch detected a warning due to assigning -EIO (a negative value) to an
> unsigned short variable, causing a type mismatch and potential issues.
> 
> In v1, the type was changed to short, which resolved the warning, but
> retained the misleading "us" prefix in the variable name.
> 
> In v2, update the type to s16 and rename the variable to SmapiOK,
> removing the "us" (unsigned short) prefix as per Greg KH suggestion.
> 
> This change ensures type correctness, avoids confusion, and improves
> overall code readability.
> 
> Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com>
> ---
> V1 - https://lore.kernel.org/all/20250409211929.213360-1-purvayeshi550@gmail.com/
> V2 - Use s16 type and rename variable to remove misleading "us" prefix.
> 
>  drivers/char/mwave/smapi.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/char/mwave/smapi.c b/drivers/char/mwave/smapi.c
> index f8d79d393b69..65bc7e1ea6cf 100644
> --- a/drivers/char/mwave/smapi.c
> +++ b/drivers/char/mwave/smapi.c
> @@ -66,7 +66,7 @@ static int smapi_request(unsigned short inBX, unsigned short inCX,
>  	unsigned short myoutDX = 5, *pmyoutDX = &myoutDX;
>  	unsigned short myoutDI = 6, *pmyoutDI = &myoutDI;
>  	unsigned short myoutSI = 7, *pmyoutSI = &myoutSI;
> -	unsigned short usSmapiOK = -EIO, *pusSmapiOK = &usSmapiOK;
> +	s16 SmapiOK = -EIO, *pSmapiOK = &SmapiOK;

Do you think that "SmapiOK" is a valid kernel variable name?  Doesn't
look ok to me, what does checkpatch.pl say?  :)

thanks,

greg k-h