[PATCH] of: match by compatible property first

[Rob Herring]

On 04/20/2012 05:21 AM, Thierry Reding wrote:
> When matching devices against an OF device ID table, the first string of
> the compatible property that is listed in the table should match,
> regardless of its position in the table.
> 
> Signed-off-by: Thierry Reding <thierry.reding at avionic-design.de>
> ---
>  drivers/of/base.c  |   31 +++++++++++++++++++++++++++----
>  include/linux/of.h |    3 +++
>  2 files changed, 30 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index d9bfd49..db355b7 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -511,6 +511,23 @@ out:
>  }
>  EXPORT_SYMBOL(of_find_node_with_property);
>  
> +const struct of_device_id *of_match_compat(const struct of_device_id *matches,
> +					   const char *compat)
> +{
> +	while (matches->name[0] || matches->type[0] || matches->compatible[0]) {

You are not using name or type here, so you can remove.

> +		const char *cp = matches->compatible;
> +		int len = strlen(cp);
> +
> +		if (len > 0 && of_compat_cmp(compat, cp, len) == 0)
> +			return matches;
> +
> +		matches++;
> +	}
> +
> +	return NULL;
> +}
> +EXPORT_SYMBOL(of_match_compat);
> +
>  /**
>   * of_match_node - Tell if an device_node has a matching of_match structure
>   *	@matches:	array of of device match structures to search in
> @@ -521,9 +538,18 @@ EXPORT_SYMBOL(of_find_node_with_property);
>  const struct of_device_id *of_match_node(const struct of_device_id *matches,
>  					 const struct device_node *node)
>  {
> +	struct property *prop;
> +	const char *cp;
> +
>  	if (!matches)
>  		return NULL;
>  
> +	of_property_for_each_string(node, "compatible", prop, cp) {
> +		const struct of_device_id *match = of_match_compat(matches, cp);
> +		if (match)
> +			return match;
> +	}
> +
>  	while (matches->name[0] || matches->type[0] || matches->compatible[0]) {

You don't need to check compatible ptr here.

>  		int match = 1;
>  		if (matches->name[0])
> @@ -532,10 +558,7 @@ const struct of_device_id *of_match_node(const struct of_device_id *matches,
>  		if (matches->type[0])
>  			match &= node->type
>  				&& !strcmp(matches->type, node->type);
> -		if (matches->compatible[0])
> -			match &= of_device_is_compatible(node,
> -						matches->compatible);
> -		if (match)
> +		if (match && !matches->compatible[0])
>  			return matches;
>  		matches++;
>  	}
> diff --git a/include/linux/of.h b/include/linux/of.h
> index bd52d83..23b5061 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -231,6 +231,8 @@ extern const void *of_get_property(const struct device_node *node,
>  
>  extern int of_n_addr_cells(struct device_node *np);
>  extern int of_n_size_cells(struct device_node *np);
> +extern const struct of_device_id *of_match_compat(
> +	const struct of_device_id *matches, const char *compat);

Why does this need to be a public function?

>  extern const struct of_device_id *of_match_node(
>  	const struct of_device_id *matches, const struct device_node *node);
>  extern int of_modalias_node(struct device_node *node, char *modalias, int len);
> @@ -395,6 +397,7 @@ static inline int of_machine_is_compatible(const char *compat)
>  }
>  
>  #define of_match_ptr(_ptr)	NULL
> +#define of_match_compat(_matches, _compat)	NULL
>  #define of_match_node(_matches, _node)	NULL
>  #define of_property_for_each_u32(np, propname, prop, p, u) \
>  	while (0)