of_property_read_bool Search for a property in a device node and read a 32-bit value from it. Returns 0 if <0> or if the property does not exist, 1 if <1> or none.
this will allow to disable a boolean is-ok; => true is-ok = <1>; => true is-ok = <0>; => false Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <[email protected]> Cc: [email protected] --- Hi, if this is ok I'll rebase my mtd and i2c patch to use it Best Regards, J. drivers/of/base.c | 30 ++++++++++++++++++++++++++++++ include/linux/of.h | 8 ++++++++ 2 files changed, 38 insertions(+), 0 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index 133908a..a0eaf08 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -686,6 +686,36 @@ int of_property_read_u64(const struct device_node *np, const char *propname, EXPORT_SYMBOL_GPL(of_property_read_u64); /** + * of_property_read_bool - Find and read a boolean from a property + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * + * Search for a property in a device node and read a 32-bit value from + * it. Returns 0 if <0> or if the property does not exist, 1 if <1> or none. + * + * is-ok; => true + * is-ok = <1>; => true + * is-ok = <0>; => false + */ +int of_property_read_bool(const struct device_node *np, const char *propname) +{ + u32 reg; + int ret = of_property_read_u32(np, propname, ®); + + switch (ret) { + case -EINVAL: + return false; + case -ENODATA: + return true; + case 0: + return reg == 1; + default: + return ret; + } +} +EXPORT_SYMBOL_GPL(of_property_read_bool); + +/** * of_property_read_string - Find and read a string from a property * @np: device node from which the property value is to be read. * @propname: name of the property to be searched. diff --git a/include/linux/of.h b/include/linux/of.h index a75a831..2e5f77b 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -210,6 +210,8 @@ extern int of_property_read_u32_array(const struct device_node *np, size_t sz); extern int of_property_read_u64(const struct device_node *np, const char *propname, u64 *out_value); +extern int of_property_read_bool(const struct device_node *np, + const char *propname); extern int of_property_read_string(struct device_node *np, const char *propname, @@ -288,6 +290,12 @@ static inline int of_property_read_u32_array(const struct device_node *np, return -ENOSYS; } +static inline int of_property_read_bool(const struct device_node *np, + const char *propname) +{ + return -ENOSYS; +} + static inline int of_property_read_string(struct device_node *np, const char *propname, const char **out_string) -- 1.7.7 _______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
