Subject: Re: [PATCH v2 1/2] Staging: comedi: comedi_fops: Change
 comedi_num_legacy_minors type
To: Cheah Kok Cheong <thrust73@gmail.com>, hsweeten@visionengravers.com,
        gregkh@linuxfoundation.org, devel@driverdev.osuosl.org
References: <cd5f3e9f6320ac0063e61f0d0457e5400091390c.1488908538.git.thrust73@gmail.com>
Cc: linux-kernel@vger.kernel.org
From: Ian Abbott <abbotti@mev.co.uk>
Message-ID: <7dba80b9-a30b-79c8-4b0b-89780ecb0e78@mev.co.uk>
Date: Wed, 8 Mar 2017 11:28:24 +0000
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On 07/03/17 18:13, Cheah Kok Cheong wrote:
> Change to unsigned to allow removal of negative value check in
> init section. Use smaller data type since the max possible
> value currently is 48.
>
> Signed-off-by: Cheah Kok Cheong <thrust73@gmail.com>
> ---
>
> V2:
> -No changes.
>
>  drivers/staging/comedi/comedi_fops.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
> index 57e8599..354d264 100644
> --- a/drivers/staging/comedi/comedi_fops.c
> +++ b/drivers/staging/comedi/comedi_fops.c
> @@ -76,8 +76,8 @@ struct comedi_file {
>  #define COMEDI_NUM_SUBDEVICE_MINORS	\
>  	(COMEDI_NUM_MINORS - COMEDI_NUM_BOARD_MINORS)
>
> -static int comedi_num_legacy_minors;
> -module_param(comedi_num_legacy_minors, int, 0444);
> +static unsigned short comedi_num_legacy_minors;
> +module_param(comedi_num_legacy_minors, ushort, 0444);
>  MODULE_PARM_DESC(comedi_num_legacy_minors,
>  		 "number of comedi minor devices to reserve for non-auto-configured devices (default 0)"
>  		);
> @@ -2857,8 +2857,7 @@ static int __init comedi_init(void)
>
>  	pr_info("version " COMEDI_RELEASE " - http://www.comedi.org\n");
>
> -	if (comedi_num_legacy_minors < 0 ||
> -	    comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) {
> +	if (comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) {
>  		pr_err("invalid value for module parameter \"comedi_num_legacy_minors\".  Valid values are 0 through %i.\n",
>  		       COMEDI_NUM_BOARD_MINORS);
>  		return -EINVAL;
>

Thanks.  (There is no harm in making the parameter unsigned short rather 
than unsigned int, although it's probably not worth it as you still need 
to check the value.  It doesn't matter either way.)

Reviewed-by: Ian Abbott <abbotti@mev.co.uk>

-- 
-=( Ian Abbott @ MEV Ltd.    E-mail: <abbotti@mev.co.uk> )=-
-=(                          Web: http://www.mev.co.uk/  )=-