[U-Boot] [PATCH v3 1/5] kirkwood: add save functionality kirkwood_mpp_conf function

[Luka Perkov]

Hi Valentin,

On Thu, May 31, 2012 at 04:17:52PM +0200, Valentin Longchamp wrote:
> If a second non NULL argument is given to the kirkwood_mpp_conf
> function, it will be used to store the current configuration of the MPP
> registers. mpp_save  must be a preallocated table of the same size as
> mpp_list and it must be zero terminated as well.
> 
> A later call to kirkwood_mpp_conf function with this saved list as first
> (mpp_conf) argment will set the configuration back.
> 
> Signed-off-by: Valentin Longchamp <valentin.longchamp at keymile.com>
> cc: Holger Brunck <holger.brunck at keymile.com>
> cc: Prafulla Wadaskar <prafulla at marvell.com>
> ---
>  arch/arm/cpu/arm926ejs/kirkwood/mpp.c    |   14 ++++++++++++--
>  arch/arm/include/asm/arch-kirkwood/mpp.h |    2 +-
>  2 files changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
> index 3da6c98..158ea84 100644
> --- a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
> +++ b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
> @@ -31,11 +31,11 @@ static u32 kirkwood_variant(void)
>  #define MPP_CTRL(i)	(KW_MPP_BASE + (i* 4))
>  #define MPP_NR_REGS	(1 + MPP_MAX/8)
>  
> -void kirkwood_mpp_conf(u32 *mpp_list)
> +void kirkwood_mpp_conf(u32 *mpp_list, u32 *mpp_save)
>  {
>  	u32 mpp_ctrl[MPP_NR_REGS];
>  	unsigned int variant_mask;
> -	int i;
> +	int i, save = 0;
>  
>  	variant_mask = kirkwood_variant();
>  	if (!variant_mask)
> @@ -48,10 +48,13 @@ void kirkwood_mpp_conf(u32 *mpp_list)
>  	}
>  	debug("\n");
>  
> +	if (mpp_save)
> +		save = 1;
>  
>  	while (*mpp_list) {
>  		unsigned int num = MPP_NUM(*mpp_list);
>  		unsigned int sel = MPP_SEL(*mpp_list);
> +		unsigned int sel_save;
>  		int shift;
>  
>  		if (num > MPP_MAX) {
> @@ -66,6 +69,13 @@ void kirkwood_mpp_conf(u32 *mpp_list)
>  		}
>  
>  		shift = (num & 7) << 2;
> +
> +		if (save) {

Why using new variable if it's only used in one place? Why not use this
here:

		if (mpp_save) {

Then we don't need save variable at all.

Luka