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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: ADT746X: logical-bitwise & confusion in set_max_duty_at_crit()
Date: Mon, 10 Mar 2008 22:56:00 +0100
To: Roel Kluin <12o3l@tiscali.nl>
Cc: lkml <linux-kernel@vger.kernel.org>, linuxppc-dev@ozlabs.org,
	Colin Leroy <colin@colino.net>, akpm@linux-foundation.org,
	"Darrick J. Wong" <djwong@us.ibm.com>
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> It includes suggested changes by Segher Boessenkool and I think this
> version was tested by Darrick J. Wong

> -	u8 reg;
> +	u8 reg, temp;
>  	struct i2c_client *client = to_i2c_client(dev);
>  	struct adt7473_data *data = i2c_get_clientdata(client);
> -	int temp = simple_strtol(buf, NULL, 10);
> -	temp = temp && 0xFF;
> +
> +	temp = simple_strtol(buf, NULL, 10) & 0xFF;

It still does this superfluous "& 0xff", which hides the lack of
range checking.


Segher