linux-kernel - Re: [PATCH] [media] mb86a20s: remove redundant check if val is less than zero

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Date:	Fri, 15 Jul 2016 16:45:42 +0100
From:	Colin Ian King <colin.king@...onical.com>
To:	Mauro Carvalho Chehab <mchehab@...pensource.com>
Cc:	Mauro Carvalho Chehab <mchehab@...nel.org>,
	linux-media@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] [media] mb86a20s: remove redundant check if val is less
 than zero

On 15/07/16 16:20, Mauro Carvalho Chehab wrote:
> Em Tue, 12 Jul 2016 10:30:51 +0100
> Colin King <colin.king@...onical.com> escreveu:
> 
>> From: Colin Ian King <colin.king@...onical.com>
>>
>> The result of mb86a20s_readreg(state, 0x0a) & 0xf is always in the range
>> 0x00 to 0x0f and can never be negative, so remove the redundant check
>> of the result being less than zero.
>>
>> Signed-off-by: Colin Ian King <colin.king@...onical.com>
>> ---
>>  drivers/media/dvb-frontends/mb86a20s.c | 2 --
>>  1 file changed, 2 deletions(-)
>>
>> diff --git a/drivers/media/dvb-frontends/mb86a20s.c b/drivers/media/dvb-frontends/mb86a20s.c
>> index fb88ddd..0205846 100644
>> --- a/drivers/media/dvb-frontends/mb86a20s.c
>> +++ b/drivers/media/dvb-frontends/mb86a20s.c
>> @@ -302,8 +302,6 @@ static int mb86a20s_read_status(struct dvb_frontend *fe, enum fe_status *status)
>>  	*status = 0;
>>  
>>  	val = mb86a20s_readreg(state, 0x0a) & 0xf;
>> -	if (val < 0)
>> -		return val;
> 
> Actually, mb86a20s_readreg() can return a negative value.

Oops, yep, clearly my code is stupid. I'll send a fix soon.

> 
> Please change the above logic to first check for the value returned
> from mb86a20s_readreg() and then apply the bitmask.
> 
> Thanks,
> Mauro
> 
>>  
>>  	if (val >= 2)
>>  		*status |= FE_HAS_SIGNAL;
> 
> 
> 
> Thanks,
> Mauro
>