[PATCH 1/2 v6] of: add helper to parse display timings

[Steffen Trumtrar]

On Fri, Oct 05, 2012 at 10:21:37AM -0600, Stephen Warren wrote:
> On 10/05/2012 10:16 AM, Steffen Trumtrar wrote:
> > On Thu, Oct 04, 2012 at 12:47:16PM -0600, Stephen Warren wrote:
> >> On 10/04/2012 11:59 AM, Steffen Trumtrar wrote:
> ...
> >>> +	for_each_child_of_node(timings_np, entry) {
> >>> +		struct signal_timing *st;
> >>> +
> >>> +		st = of_get_display_timing(entry);
> >>> +
> >>> +		if (!st)
> >>> +			continue;
> >>
> >> I wonder if that shouldn't be an error?
> > 
> > In the sense of a pr_err not a -EINVAL I presume?! It is a little bit quiet in
> > case of a faulty spec, that is right.
> 
> I did mean return an error; if we try to parse something and can't,
> shouldn't we return an error?
> 
> I suppose it may be possible to limp on and use whatever subset of modes
> could be parsed and drop the others, which is what this code does, but
> the code after the loop would definitely return an error if zero timings
> were parseable.

If a display supports multiple modes, I think it is better to have a working
mode (even if it is not the preferred one) than have none at all.
If there is no mode at all, that should be an error, right.

Regards,
Steffen

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