Re: [PATCH] powerpc: booke_wdt: Fix build error as a module

[Guenter <linux@roeck-us.net>]

On Wed, Aug 20, 2014 at 12:55:44PM -0400, Pranith Kumar wrote:
> Building booke_wdt fails when trying to build as a module as there is no
> early_param() in module. Fix by using module_param() instead of early_param().
> 
> Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
> CC: Guenter Roeck <linux@roeck-us.net>
> ---
>  drivers/watchdog/booke_wdt.c | 28 +++++-----------------------
>  1 file changed, 5 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/watchdog/booke_wdt.c b/drivers/watchdog/booke_wdt.c
> index 08a7853..65f5e9f 100644
> --- a/drivers/watchdog/booke_wdt.c
> +++ b/drivers/watchdog/booke_wdt.c
> @@ -30,8 +30,6 @@
>   * occur, and the final time the board will reset.
>   */
>  
> -u32 booke_wdt_enabled;
> -u32 booke_wdt_period = CONFIG_BOOKE_WDT_DEFAULT_TIMEOUT;
>  
>  #ifdef	CONFIG_PPC_FSL_BOOK3E
>  #define WDTP(x)		((((x)&0x3)<<30)|(((x)&0x3c)<<15))
> @@ -41,27 +39,10 @@ u32 booke_wdt_period = CONFIG_BOOKE_WDT_DEFAULT_TIMEOUT;
>  #define WDTP_MASK	(TCR_WP_MASK)
>  #endif
>  
> -/* Checks wdt=x and wdt_period=xx command-line option */
> -notrace int __init early_parse_wdt(char *p)
> -{
> -	if (p && strncmp(p, "0", 1) != 0)
> -		booke_wdt_enabled = 1;
> -
> -	return 0;
> -}
> -early_param("wdt", early_parse_wdt);
> -
> -int __init early_parse_wdt_period(char *p)
> -{
> -	unsigned long ret;
> -	if (p) {
> -		if (!kstrtol(p, 0, &ret))
> -			booke_wdt_period = ret;
> -	}
> -
> -	return 0;
> -}
> -early_param("wdt_period", early_parse_wdt_period);
> +static bool booke_wdt_enabled = true;

Any reason for changing the default from false to true ? 
Unless you have a reaslly good reason, I don't think that is a good idea.

> +module_param(booke_wdt_enabled, bool, 0444);
> +static int  booke_wdt_period = CONFIG_BOOKE_WDT_DEFAULT_TIMEOUT;
> +module_param(booke_wdt_period, int, 0444);
>  
Also not sure if it adds value to have the module parameters visible
from user space. Why not use 0 for the permission flags ?

Thanks,
Guenter