> Yann, if you could have a look at and comment on my patch, I would be
> glad.
>
> Dirk
>
> From 3e555d59dd651366e14d6d6a47668acec3039fff Mon Sep 17 00:00:00 2001
> From: Dirk Gouders <dirk@gouders.net>
> Date: Wed, 30 Oct 2013 10:44:54 +0100
> Subject: [PATCH] kconfig/symbol.c: handle choice_values that depend on 'm'
>  symbols
>
> If choices consist of choice_values that depend on symbols set to 'm',
> those choice_values are not set to 'n' if the choice is changed from
> 'm' to 'y' (in which case only one active choice_value is allowed).
> Those values are also written to the config file causing modules when
> they should not.
>
> The following config can be used to reproduce and examine the problem:
>
> config modules
> 	boolean modules
> 	default y
> 	option modules
>
> config dependency
> 	tristate "Dependency"
> 	default m
>
> choice
> 	prompt "Tristate Choice"
> 	default choice0
>
> config choice0
> 	tristate "Choice 0"
>
> config choice1
> 	tristate "Choice 1"
> 	depends on dependency
>
> endchoice
>
> This patch handles choice_values that depend on symbols set to 'm' if
> the corresponding choice is set to 'y'.
>
> Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Signed-off-by: Dirk Gouders <dirk@gouders.net>
> ---
>  scripts/kconfig/symbol.c | 26 ++++++++++++++++++++++----
>  1 file changed, 22 insertions(+), 4 deletions(-)
>
> diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
> index c9a6775..043c041 100644
> --- a/scripts/kconfig/symbol.c
> +++ b/scripts/kconfig/symbol.c
> @@ -338,10 +338,27 @@ void sym_calc_value(struct symbol *sym)
>  
>  	switch (sym_get_type(sym)) {
>  	case S_BOOLEAN:
> -	case S_TRISTATE:
> -		if (sym_is_choice_value(sym) && sym->visible == yes) {
> -			prop = sym_get_choice_prop(sym);
> -			newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
> +	case S_TRISTATE: {
> +		struct symbol *choice_sym = NULL;
> +
> +		if (sym_is_choice_value(sym))
> +			choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
> +
> +		/*
> +		 * If this is a visible choice_value we want to check
> +		 * if it is the currently selected, in two cases:
> +		 *
> +		 * 1) If it's visibility is 'yes'.
> +		 * 2) If it's visibility is 'mod' and the correspondig
> +		 *    choice symbols' value is 'yes'.
> +		 *
> +		 *    If a choice symbol is 'yes', only the selected
> +		 *    choice_value may be 'yes' and all others (also
> +		 *    those currently set to 'mod') must be set to 'no'.
> +		 */
> +		if (choice_sym &&
> +		    (sym->visible == yes || (sym->visible == mod && choice_sym->curr.tri == yes))) {
> +			    newval.tri = choice_sym->curr.val == sym ? yes : no;
>  		} else {
>  			if (sym->visible != no) {
>  				/* if the symbol is visible use the user value
> @@ -382,6 +399,7 @@ void sym_calc_value(struct symbol *sym)
>  		if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
>  			newval.tri = yes;
>  		break;
> +	}
>  	case S_STRING:
>  	case S_HEX:
>  	case S_INT: