On Fri, Dec 02, 2016 at 10:22:30PM +0800, Icenowy Zheng wrote:

01.12.2016, 17:36, "Maxime Ripard" [off-list ref]:

quoted

On Mon, Nov 28, 2016 at 12:29:07AM +0000, Andr? Przywara wrote:

quoted

?> Something more interesting happened.
?>
?> Xunlong made a add-on board for Orange Pi Zero, which exposes the
?> two USB Controllers exported at expansion bus as USB Type-A
?> connectors.
?>
?> Also it exposes a analog A/V jack and a microphone.
?>
?> Should I enable {e,o}hci{2.3} in the device tree?

?Actually we should do this regardless of this extension board. The USB
?pins are not multiplexed and are exposed on user accessible pins (just
?not soldered, but that's a detail), so I think they qualify for DT
?enablement. And even if a user can't use them, it doesn't hurt to have
?them (since they are not multiplexed).

My main concern about this is that we'll leave regulators enabled by
default, for a minority of users. And that minority will prevent to do
a proper power management when the times come since we'll have to keep
that behaviour forever.

I think these users can add a 'fdt set /xxx/xxx status "disabled" ' .

You can't ask that from the majority of users. These users will take
debian or fedora, install it, and expect everything to work
properly. I would make the opposite argument actually. If someone is
knowledgeable enough to solder the USB pins a connector, then (s)he'll
be able to make that u-boot call.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
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