Re: [PATCH v3 07/17] xen/device-tree: Add dt_property_read_u32_array helper

[Bertrand Marquis <Bertrand.Marquis@xxxxxxx>]

Hi Rahul,

> On 28 Sep 2021, at 19:18, Rahul Singh <rahul.singh@xxxxxxx> wrote:
> 
> Based Linux commit a67e9472da423ec47a3586920b526ebaedf25fc3
> 
> Import the Linux helper of_property_read_u32_array. This function find
> and read an array of 32 bit integers from a property.
> 
> Signed-off-by: Rahul Singh <rahul.singh@xxxxxxx>
Reviewed-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>

Cheers
Bertrand

> ---
> Change in v3:
> - Modify commit message to include upstream Linux commit-id not stable
>  Linux commit-id
> Change in v2: Patch introduced in v2
> ---
> xen/include/xen/device_tree.h | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
> 
> diff --git a/xen/include/xen/device_tree.h b/xen/include/xen/device_tree.h
> index 1693fb8e8c..3ffe3eb3d2 100644
> --- a/xen/include/xen/device_tree.h
> +++ b/xen/include/xen/device_tree.h
> @@ -392,6 +392,36 @@ int dt_property_read_variable_u32_array(const struct 
> dt_device_node *np,
>                                         const char *propname, u32 *out_values,
>                                         size_t sz_min, size_t sz_max);
> 
> +/**
> + * dt_property_read_u32_array - Find and read an array of 32 bit integers
> + * from a property.
> + *
> + * @np:     device node from which the property value is to be read.
> + * @propname:   name of the property to be searched.
> + * @out_values: pointer to return value, modified only if return value is 0.
> + * @sz:     number of array elements to read
> + *
> + * Search for a property in a device node and read 32-bit value(s) from
> + * it.
> + *
> + * Return: 0 on success, -EINVAL if the property does not exist,
> + * -ENODATA if property does not have a value, and -EOVERFLOW if the
> + * property data isn't large enough.
> + *
> + * The out_values is modified only if a valid u32 value can be decoded.
> + */
> +static inline int dt_property_read_u32_array(const struct dt_device_node *np,
> +                                             const char *propname,
> +                                             u32 *out_values, size_t sz)
> +{
> +    int ret = dt_property_read_variable_u32_array(np, propname, out_values,
> +                              sz, 0);
> +    if ( ret >= 0 )
> +        return 0;
> +    else
> +        return ret;
> +}
> +
> /**
>  * dt_property_read_bool - Check if a property exists
>  * @np: node to get the value
> -- 
> 2.17.1
>