Change the device tree for DisplayPort on DP1?

Okay, I will do that.
Thanks!

Hi wayneWWW,

I think we have a partial success!
i have coupled sor1 with dc@54240000
I got the first time via dmesg an extcon-gpio-states output.

dmesg:

[ 70.118521] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 70.298519] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 116.086508] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 116.410520] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 135.314519] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 136.074510] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 136.194202] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 136.946502] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 137.090498] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 137.574501] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 138.086499] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 138.742498] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 139.750499] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
[ 143.186507] extcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0

But it’s funny sometimes it recognizes an extcon-gpio-states and sometimes not ??? something is wrong…
I don’t understand this yet…

I do not have a picture yet but it may be that I still have something forgotten

Hi wayneWWW,

Maybe something is wrong with the display…

The display that comes from a major manufacturer connect internally PIN 5/11/2/8/16 GND from DisplayPort connector with the external grounding of the supply voltage of 230V!

This of course messes up the whole circuit and should Vesa-Norm not be so ! why the manufacturer does so I do not know

I really need to get another display…

Could you also dump the dpaux_regs again when you see extcon gpio shows something? Also, could you share me the full dmesg and full dts for current setup?

Besides the log and the dts files, please also check if you really see gpio extcon when you do the hotplug…

Because extcon@1 is actually the function for usb. Not related to DP at all.

hardware/nvidia/platform/t210/porg/kernel-dts/porg-platforms/tegra210-porg-extcon-p3448-0000-a00.dtsi
vbus_id_gpio_extcon: extcon@1 {
compatible = “extcon-gpio-states”;

Please check if you still write CC1 pin for the hpd but not something else.

nvidia,hpd-gpio = <&gpio TEGRA_GPIO(CC, 1) 1>; /* PN7 */

Hi,

I have coupled sor1 with dc@54240000.
currently tegra_dp0 is still displayed?
Although I am coupled with dc@54240000 (tegradc.1)

dp0

Here is the current .dts file:

dts_output_12.11.2021.txt (326.6 KB)

and the dmesg log:

dmesg_output_2021-11-12_12-06-42.log (54.7 KB)

Oh, that’s right of course, I have now removed the USB line and the external circuit for vbus_id_gpio_extcon removed, now nothing is logged → xtcon-gpio-states extcon:extcon@1: Cable state:0, cable id:0
We should quickly forget that this has nothing to do with HPD.

Ok, looks like still not work. I may give out another test next Monday.

But I also have one question about a new log here. Though it may not resolve the issue…

Could you check why below error log was not showing up in your previous log when it was on tegradc.0? You may need to add some log to the kernel driver to see why it didn’t show up at that time…

[ 1.072878] tegradc tegradc.1: Display dc.ffffff800ab80000 registered with id=0
[ 1.073381] tegradc tegradc.1: dc_dp_out_hotplug_init: couldn’t get regulator vdd_hdmi_5v0
[ 1.080543] tegradc tegradc.1: probed

Hi,

unfortunately it does not work (yet), I am glad that you support me :-) thank you!

You are right that I did not notice. I forgot something, at tegradc.0 I still have in the file tegra210-porg-power-tree-p3448-0000-a00.dtsi

vdd_hdmi_5v0-supply = <&p3449_vdd_hdmi> changed to
vdd_hdmi_5v0-supply = <&battery_reg>

now the message dc_dp_out_hotplug_init: couldn’t get regulator vdd_hdmi_5v0 is no longer there.

here is the latest dmesg log:

dmesg_output_2021-11-14_11-44-06.log (52.9 KB)

Hi,
i have not yet understood where the dpaux_regs deviations come from?

For any register mentioned in this topic, you can find the definition in the TRM document.

Please refer to DPAUX_DP_AUXCTL_0 and DPAUX_DP_AUXADDR_0 in section 27.

I am also wondering one test here. Not sure if you can test the same hardware from DP1 to DP0?
My purpose here is just to validate whether this hardware is able to trigger hotplug event over DP0. Which we have validated over devkit and many other custom boards.

Hi,

I also looked it up in the TRM yesterday.

I just wanted to understand if this has internal effects, of course I can test the hardware from DP1 to DP0. but have not found any differences. i also only focus on the hotplug envent.

Did you mean your hardware even not able to see hotplug even when you used DP0?

No, that’s not what I meant, on the new board there is only one DisplayPort on DP1. On another board DP0 works of course.

Yes, my point is if this would take too much efforts to test the same design on DP0 on this board. This is to validate that everything on the hardware is correct or not.

okay, now i get it :-) That’s a lot of effort. I just find it so depressing, if we used DP0 and the nvidea devkit .dts the DisplayPort on DP0 would work very well. But now we do not have this case our displyport is connected to DP1. i already thought about reconnecting the displayport to DP0. then we might have solved it faster. But we come unfortunately montan very difficult to electronics components, so that a new board takes a lot of time.

Is it right if we take DP0 there is no audio support?

Yes, there would be no audio support.

I am still discussing with internal team if we have anything that could check over DP1. They may give reply today (timezone PT).

Hi,

thank you very much. You have a lot of patience with me.
i don’t think i would have the patience :-)

Hi @ElectronicSystems ,

Just want to know do you have to use DP1 for DP? Is it possible to move to DP0 but with no audio support?

We are still doing hardware check internally so still take times.

Hi WayneWWW,

we need the audio support unfortunately so we depend on DP1.

Please take your time, we are glad that you help us.