On Wed, Sep 2, 2015 at 11:27 PM, Yakir Yang <ykk@xxxxxxxxxxxxxx> wrote:
Hi Rob,Ideally, you would be able to just retrieve this quirk from the
å 09/03/2015 04:17 AM, Rob Herring åé:
On Tue, Sep 1, 2015 at 1:14 AM, Yakir Yang <ykk@xxxxxxxxxxxxxx> wrote:
Some edp screen do not have hpd signal, so we can't just returnThis is a property of the panel (or connector perhaps), so this
failed when hpd plug in detect failed.
property should be located there. At least, it is a common issue and
not specific to this chip. We could have an HDMI connector and failed
to hook up HPD for example. A connector node is also where hpd-gpios
should be located instead (and are already defined by
../bindings/video/hdmi-connector.txt). Perhaps we need a eDP connector
Yep, I agree with your front point, it is a property of panel, not specific
to eDP controller, so this code should handle in connector logic.
But another question, if we just leave this property to connector,
then we would need to parse this property in analogix_dp-rockchip.c,
and then make an hook in analogix_dp_core.c driver. This is not nice,
and if there are some coming platform which alse want to use analogix_dp
code and meet this "no-hpd" situation, then they would need duplicate
to parse this property and fill the hook in analogix_dp_core.c driver.
So it's little bit conflict :-)
connector or panel. Getting this property from your node vs. the port
you are attached to should not be much harder. Either the connector
struct can have this info or there can be a DT function that can walk
the graph and get it. Just don't open code the graph traversal in your
Beside I can not understand your example very well. Do you meanI don't know that there is h/w, but it is always possible HPD is not
that there are some HDMI monitor which also do not have HPD
signal (just like some eDP panel do not have hpd too), and then
the "hpd-gpios" ? Hmm... I don't know how the "hpd-gpios" want
to help in this case, would you mind show some sample code :-D
hooked up or hooked up incorrectly some how.
If there is no HPD support, then hpd-gpios is not going to help you.
I think there are 3 cases to handle:
- HPD handled by bridge chip - The bridge driver knows it has this
capability. No DT properties are needed and no HPD properties on the
connector node imply the bridge chip should handle HPD functions.
- HPD handled by GPIO line (or some other block) - Indicated by
- No or broken HPD - Indicated by "hpd-force" property.
Yes, and as Thierry pointed out we may need to know the exact panel even.Are there any eDP panels which don't have EDID and need panel details in
Oh, I think you want to collect some info that belong to panel
property but no indicate in panel EDID message, so those can
be collect in eDP connector binding, is it right ?