[RFC PATCH v3 1/5] dt: add of_get_child_count helper function

Dong Aisheng-B29396 B29396 at freescale.com
Tue Dec 20 22:18:19 EST 2011


> -----Original Message-----
> From: Stephen Warren [mailto:swarren at nvidia.com]
> Sent: Wednesday, December 21, 2011 7:59 AM
> To: Dong Aisheng-B29396; linux-kernel at vger.kernel.org
> Cc: linus.walleij at stericsson.com; s.hauer at pengutronix.de;
> rob.herring at calxeda.com; linux-arm-kernel at lists.infradead.org;
> kernel at pengutronix.de; cjb at laptop.org; devicetree-discuss at lists.ozlabs.org
> Subject: RE: [RFC PATCH v3 1/5] dt: add of_get_child_count helper function
> Importance: High
> 
> Dong Aisheng wrote at Tuesday, December 20, 2011 10:41 AM:
> > From: Dong Aisheng <dong.aisheng at linaro.org>
> >
> > Currently most code to get child count in kernel are almost same, add
> > a helper to implement this function for dt to use.
> 
> > diff --git a/include/linux/of.h b/include/linux/of.h
> 
> > +static inline int of_get_child_count(const struct device_node *np) {
> > +	return -ENOSYS;
> > +}
> 
> Wouldn't it be better to return 0 here? -ENOSYS would be fine if the function
> returned an error code, but it's really returning a count, and other "dummy"
> functions that return data return 0/NULL already. This would also allow you to
> just use the value directly in all cases rather than having to check for a < 0
> error case.
> 
Good point.
Will update it next.

Regards
Dong Aisheng





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