Re: [PATCH] of: add 'const' for of_property_*_string*() parameter '*np'
From: Rob Herring
Date: Thu Mar 03 2016 - 08:53:19 EST
On Wed, Mar 2, 2016 at 3:35 PM, David Rivshin (Allworx)
<drivshin.allworx@xxxxxxxxx> wrote:
> From: David Rivshin <drivshin@xxxxxxxxxxx>
>
> The of_property_{read,count,match}_string* family of functions never
> modify the struct device_node pointer that is passed in, so there is no
> reason for it to be non-const. Equivalent functions for all other types
> already take a 'const struct device_node *np'.
>
> Signed-off-by: David Rivshin <drivshin@xxxxxxxxxxx>
> ---
>
> MAINTAINTERS says that the appropriate tree is
> git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux.git
Yes, we probably need to update that.
> but it looks like that hasn't been updated in a while. So this patch
> is based off the "for-next" branch of
> git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git
> instead. Let me know if you need me to respin from another tree/branch.
You should base off of Linus' tree unless you have some dependency. I
doubt it matters in this case, so no need to resend.
>
> drivers/of/base.c | 15 ++++++++-------
> include/linux/of.h | 18 +++++++++---------
> 2 files changed, 17 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index 017dd94..b299de2 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -1341,10 +1341,10 @@ EXPORT_SYMBOL_GPL(of_property_read_u64_array);
> *
> * The out_string pointer is modified only if a valid string can be decoded.
> */
> -int of_property_read_string(struct device_node *np, const char *propname,
> +int of_property_read_string(const struct device_node *np, const char *propname,
> const char **out_string)
> {
> - struct property *prop = of_find_property(np, propname, NULL);
> + const struct property *prop = of_find_property(np, propname, NULL);
> if (!prop)
> return -EINVAL;
> if (!prop->value)
> @@ -1365,10 +1365,10 @@ EXPORT_SYMBOL_GPL(of_property_read_string);
> * This function searches a string list property and returns the index
> * of a specific string value.
> */
> -int of_property_match_string(struct device_node *np, const char *propname,
> +int of_property_match_string(const struct device_node *np, const char *propname,
> const char *string)
> {
> - struct property *prop = of_find_property(np, propname, NULL);
> + const struct property *prop = of_find_property(np, propname, NULL);
> size_t l;
> int i;
> const char *p, *end;
> @@ -1404,10 +1404,11 @@ EXPORT_SYMBOL_GPL(of_property_match_string);
> * Don't call this function directly. It is a utility helper for the
> * of_property_read_string*() family of functions.
> */
> -int of_property_read_string_helper(struct device_node *np, const char *propname,
> - const char **out_strs, size_t sz, int skip)
> +int of_property_read_string_helper(const struct device_node *np,
> + const char *propname, const char **out_strs,
> + size_t sz, int skip)
> {
> - struct property *prop = of_find_property(np, propname, NULL);
> + const struct property *prop = of_find_property(np, propname, NULL);
> int l = 0, i = 0;
> const char *p, *end;
>
> diff --git a/include/linux/of.h b/include/linux/of.h
> index dc6e396..7fcb681 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -296,13 +296,13 @@ extern int of_property_read_u64_array(const struct device_node *np,
> u64 *out_values,
> size_t sz);
>
> -extern int of_property_read_string(struct device_node *np,
> +extern int of_property_read_string(const struct device_node *np,
> const char *propname,
> const char **out_string);
> -extern int of_property_match_string(struct device_node *np,
> +extern int of_property_match_string(const struct device_node *np,
> const char *propname,
> const char *string);
> -extern int of_property_read_string_helper(struct device_node *np,
> +extern int of_property_read_string_helper(const struct device_node *np,
> const char *propname,
> const char **out_strs, size_t sz, int index);
> extern int of_device_is_compatible(const struct device_node *device,
> @@ -538,14 +538,14 @@ static inline int of_property_read_u64_array(const struct device_node *np,
> return -ENOSYS;
> }
>
> -static inline int of_property_read_string(struct device_node *np,
> +static inline int of_property_read_string(const struct device_node *np,
> const char *propname,
> const char **out_string)
> {
> return -ENOSYS;
> }
>
> -static inline int of_property_read_string_helper(struct device_node *np,
> +static inline int of_property_read_string_helper(const struct device_node *np,
> const char *propname,
> const char **out_strs, size_t sz, int index)
> {
> @@ -571,7 +571,7 @@ static inline int of_property_read_u64(const struct device_node *np,
> return -ENOSYS;
> }
>
> -static inline int of_property_match_string(struct device_node *np,
> +static inline int of_property_match_string(const struct device_node *np,
> const char *propname,
> const char *string)
> {
> @@ -773,7 +773,7 @@ static inline int of_property_count_u64_elems(const struct device_node *np,
> *
> * If @out_strs is NULL, the number of strings in the property is returned.
> */
> -static inline int of_property_read_string_array(struct device_node *np,
> +static inline int of_property_read_string_array(const struct device_node *np,
> const char *propname, const char **out_strs,
> size_t sz)
> {
> @@ -792,7 +792,7 @@ static inline int of_property_read_string_array(struct device_node *np,
> * does not have a value, and -EILSEQ if the string is not null-terminated
> * within the length of the property data.
> */
> -static inline int of_property_count_strings(struct device_node *np,
> +static inline int of_property_count_strings(const struct device_node *np,
> const char *propname)
> {
> return of_property_read_string_helper(np, propname, NULL, 0, 0);
> @@ -816,7 +816,7 @@ static inline int of_property_count_strings(struct device_node *np,
> *
> * The out_string pointer is modified only if a valid string can be decoded.
> */
> -static inline int of_property_read_string_index(struct device_node *np,
> +static inline int of_property_read_string_index(const struct device_node *np,
> const char *propname,
> int index, const char **output)
> {
> --
> 2.5.0
>