Re: [PATCH 1/3] of: base: add support to get machine compatible string

[Sekhar Nori]

Hi Sudeep,

On Tuesday 22 November 2016 04:23 PM, Sudeep Holla wrote:
> 
> 
> On 22/11/16 10:41, Bartosz Golaszewski wrote:
>> Add a function allowing to retrieve the compatible string of the root
>> node of the device tree.
>>
> 
> Rob has queued [1] and it's in -next today. You can reuse that if you
> are planning to target this for v4.11 or just use open coding in your
> driver for v4.10 and target this move for v4.11 to avoid cross tree
> dependencies as I already mentioned in your previous thread.

I dont have your original patch in my mailbox, but I wonder if 
returning a pointer to property string for a node whose reference has 
already been released is safe to do? Probably not an issue for the root 
node, but still feels counter-intuitive.

This is the code for reference:

+int of_machine_get_model_name(const char **model)
+{
+       int error;
+
+       if (!of_node_get(of_root))
+               return -EINVAL;
+
+       error = of_property_read_string(of_root, "model", model);
+       if (error)
+               error = of_property_read_string_index(of_root, "compatible",
+                                                     0, model);
+       of_node_put(of_root);
+
+       return error;
+}
+EXPORT_SYMBOL(of_machine_get_model_name);

Thanks,
Sekhar