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SubjectRe: [PATCH 1/1] of: Add a function to read 64-bit arrays
Date
On Fri,  3 Oct 2014 00:59:23 +0300
, Sakari Ailus <sakari.ailus@iki.fi>
wrote:
> Implement of_property_read_u64_array() for reading 64-bit arrays.
>
> This is needed for e.g. reading the valid link frequencies in the smiapp
> driver.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>

A patch that adds this function is alread part of the device properties
API patch series that will be merged for v3.19.

g.

> ---
> Hi,
>
> While the smiapp (found in drivers/media/i2c/smiapp/) OF support which needs
> this isn't in yet, other drivers such as mt9v032 which would be reading the
> valid link frequency control values will need reading arrays. This might
> make it to v4l2-of.c in the end.
>
> drivers/of/base.c | 44 ++++++++++++++++++++++++++++++++++++--------
> include/linux/of.h | 3 +++
> 2 files changed, 39 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index d8574ad..35e24f4 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -1214,6 +1214,41 @@ int of_property_read_u32_array(const struct device_node *np,
> EXPORT_SYMBOL_GPL(of_property_read_u32_array);
>
> /**
> + * of_property_read_u64_array - Find and read an array of 64 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 64-bit value(s) from
> + * it. Returns 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.
> + */
> +int of_property_read_u64_array(const struct device_node *np,
> + const char *propname, u64 *out_value, size_t sz)
> +{
> + const __be32 *val = of_find_property_value_of_size(
> + np, propname, sz * sizeof(*out_value));
> +
> + if (IS_ERR(val))
> + return PTR_ERR(val);
> +
> + while (sz--) {
> + *out_value = of_read_number(val, 2);
> + out_value++;
> + val += 2;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(of_property_read_u64_array);
> +
> +/**
> * of_property_read_u64 - Find and read a 64 bit integer from a property
> * @np: device node from which the property value is to be read.
> * @propname: name of the property to be searched.
> @@ -1229,14 +1264,7 @@ EXPORT_SYMBOL_GPL(of_property_read_u32_array);
> int of_property_read_u64(const struct device_node *np, const char *propname,
> u64 *out_value)
> {
> - const __be32 *val = of_find_property_value_of_size(np, propname,
> - sizeof(*out_value));
> -
> - if (IS_ERR(val))
> - return PTR_ERR(val);
> -
> - *out_value = of_read_number(val, 2);
> - return 0;
> + return of_property_read_u64_array(np, propname, out_value, 1);
> }
> EXPORT_SYMBOL_GPL(of_property_read_u64);
>
> diff --git a/include/linux/of.h b/include/linux/of.h
> index 6c4363b..e84533f 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -263,6 +263,9 @@ 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_u64_array(const struct device_node *np,
> + const char *propname, u64 *out_value,
> + size_t sz);
>
> extern int of_property_read_string(struct device_node *np,
> const char *propname,
> --
> 1.7.10.4
>
> --
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