Re: [PATCH Resend V2] dt: add helper function to read u8 & u16 variables & arrays

On 6 November 2012 19:48, Rob Herring robherring2@gmail.com wrote:

...

diff --git a/drivers/of/base.c b/drivers/of/base.c

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+#define of_property_read_array(_np, _pname, _out, _sz)

  \

...

• struct property *_prop = of_find_property(_np, _pname, NULL);   \
  

• const __be32 *_val;                                             \
  

•                                                                 \
  

• if (!_prop)                                                     \
  

•         return -EINVAL;                                         \
  

• if (!_prop->value)                                              \
  

•         return -ENODATA;                                        \
  

• if ((_sz * sizeof(*_out)) > _prop->length)                      \
  

•         return -EOVERFLOW;                                      \
  

•                                                                 \
  

• _val = _prop->value;                                            \
  

• while (_sz--)                                                   \
  

•         *_out++ = (typeof(*_out))be32_to_cpup(_val++);          \
  

This will not work. You are incrementing _out by 1, 2, or 4 bytes, but _val is always incremented by 4 bytes.

According to the dtc commit adding this feature, the values are packed:

With this patch the following property assignment:

property = /bits/ 16 <0x1234 0x5678 0x0 0xffff>;

is equivalent to:

property = <0x12345678 0x0000ffff>;

Something which i haven't expected :( I will fix and test it well for all types before sending it now.

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+/**

• • 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.

...

Missing sz

Yes for both misses.