Commit 86b9d170 authored by Enric Balletbo i Serra's avatar Enric Balletbo i Serra Committed by Lee Jones
Browse files

mfd: syscon: Add syscon_regmap_lookup_by_phandle_optional() function. 



This adds syscon_regmap_lookup_by_phandle_optional() function to get an
optional regmap.

It behaves the same as syscon_regmap_lookup_by_phandle() except where
there is no regmap phandle. In this case, instead of returning -ENODEV,
the function returns NULL. This makes error checking simpler when the
regmap phandle is optional.

Suggested-by: default avatarNicolas Boichat <drinkcat@chromium.org>
Signed-off-by: default avatarEnric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: default avatarMatthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
parent 3650b228

drivers/mfd/syscon.c

+18 −0
Original line number Diff line number Diff line
@@ -255,6 +255,24 @@ struct regmap *syscon_regmap_lookup_by_phandle_args(struct device_node *np, 
}

EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle_args);



/*

 * It behaves the same as syscon_regmap_lookup_by_phandle() except where

 * there is no regmap phandle. In this case, instead of returning -ENODEV,

 * the function returns NULL.

 */

struct regmap *syscon_regmap_lookup_by_phandle_optional(struct device_node *np,

					const char *property)

{

	struct regmap *regmap;



	regmap = syscon_regmap_lookup_by_phandle(np, property);

	if (IS_ERR(regmap) && PTR_ERR(regmap) == -ENODEV)

		return NULL;



	return regmap;

}

EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle_optional);



static int syscon_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

include/linux/mfd/syscon.h

+11 −0
Original line number Diff line number Diff line
@@ -28,6 +28,9 @@ extern struct regmap *syscon_regmap_lookup_by_phandle_args( 
					const char *property,

					int arg_count,

					unsigned int *out_args);

extern struct regmap *syscon_regmap_lookup_by_phandle_optional(

					struct device_node *np,

					const char *property);

#else

static inline struct regmap *device_node_to_regmap(struct device_node *np)

{
@@ -59,6 +62,14 @@ static inline struct regmap *syscon_regmap_lookup_by_phandle_args( 
{

	return ERR_PTR(-ENOTSUPP);

}



static inline struct regmap *syscon_regmap_lookup_by_phandle_optional(

					struct device_node *np,

					const char *property)

{

	return NULL;

}



#endif



#endif /* __LINUX_MFD_SYSCON_H__ */