On Tue, 2012-11-20 at 10:15 +0530, Viresh Kumar wrote:
This adds following helper routines:
- of_property_read_u8_array()
- of_property_read_u16_array()
- of_property_read_u8()
- of_property_read_u16()
This expects arrays from DT to be passed as:
- u8 array: property = /bits/ 8 <0x50 0x60 0x70>;
- u16 array: property = /bits/ 16 <0x5000 0x6000 0x7000>;
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
V2->V3:
- Expect u8 & u16 arrays to be passed using: /bits/ 8 or 16
- remove common macro, as not much common now :(
You could at least create macro to do a precheck if you want to.
Like #define CHECK_PROP(prop, sz, out)
{ if (!prop) return -EINVAL; if (!prop->value) return -ENODATA; if ((sz * sizeof(*out)) > prop->length) return -EOVERFLOW; }
Of course you can do even robust macro to cover types, but I don't like ugly macros (as I can't see how it could be shaped nicely).
- Tested on ARM platform.
--- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -671,12 +671,89 @@ struct device_node *of_find_node_by_phandle(phandle handle) EXPORT_SYMBOL(of_find_node_by_phandle); /**
- of_property_read_u8_array - Find and read an array of u8 from a property.
- @np: device node from which the property value is to be read.
- @propname: name of the property to be searched.
- @out_value: 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 8-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.
- dts entry of array should be like:
- property = /bits/ 8 <0x50 0x60 0x70>;
- The out_value is modified only if a valid u8 value can be decoded.
- */
+int of_property_read_u8_array(const struct device_node *np,
const char *propname, u8 *out_values, size_t sz)+{
- struct property *prop = of_find_property(np, propname, NULL);
- const u8 *val;
- if (!prop)
return -EINVAL;- if (!prop->value)
return -ENODATA;- if ((sz * sizeof(*out_values)) > prop->length)
return -EOVERFLOW;- val = prop->value;
- while (sz--)
*out_values++ = *val++;- return 0;
+} +EXPORT_SYMBOL_GPL(of_property_read_u8_array);
+/**
- of_property_read_u16_array - Find and read an array of u16 from a property.
- @np: device node from which the property value is to be read.
- @propname: name of the property to be searched.
- @out_value: 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 16-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.
- dts entry of array should be like:
- property = /bits/ 16 <0x5000 0x6000 0x7000>;
- The out_value is modified only if a valid u16 value can be decoded.
- */
+int of_property_read_u16_array(const struct device_node *np,
const char *propname, u16 *out_values, size_t sz)+{
- struct property *prop = of_find_property(np, propname, NULL);
- const __be16 *val;
- if (!prop)
return -EINVAL;- if (!prop->value)
return -ENODATA;- if ((sz * sizeof(*out_values)) > prop->length)
return -EOVERFLOW;- val = prop->value;
- while (sz--)
*out_values++ = be16_to_cpup(val++);- return 0;
+} +EXPORT_SYMBOL_GPL(of_property_read_u16_array);
+/**
- of_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_value: 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. Returns 0 on success, -EINVAL if the property does not exist,