Can't adjust Apple Cinema Display brightness after waking from sleep

[tilleynj]

I have the same issue-- 10.14.4 on 2015 rMBP 15" with 30" Cinema HD 2560x1600 display connected via mini DisplayPort. using machine in clamshell mode. i have the landingzone pro dock. Fresh boot -- everything is great (really -- i love this old display)

Every morning i come in to the office, connect to the dock in clamshell mode having manually put the machine to sleep about 14 hours prior and wake it using mouse (bluetooth or USB makes no difference). I hate opening the laptop because i do run parallels and i can't find the right setting to use both retina display and cinema display without going blind or tearing out my eyeballs. I *think* since the .4 update, i've been having the issue with cinema display being at the lowest brightness after wake from sleep and my only recourse to be a reboot.

Enabling / disabling night shift had no effect and neither the sudo command nor force stop from activity monitor for corebrightnessd have any impact for me.

i did notice that if i'm persistent on my keyboard, i can not only get the brightness OSD to appear, but pressing the key fast enough, i can get two or three bars to appear before it adjusts itself away.

For me, I discovered the slider in system preferences DOES change the brightness, but it just dims itself again to the lowest brightness, and the slider (only) moves itself down to about 10% lower than wherever i drop it).

I figured it must be adjusting brightness using webcam as ambient light sensor (either the usb one i have on cinema display or the one that is on the laptop display (which again is in clamshell, so 'dark' would be appropriate if that's what it's doing)

i can't reboot right now, but if it could, I'd disconnect from the dock, reboot, turn off auto-brightness on the laptop itself, reboot again, connect to the dock, reboot in clamshell and see if that has any impact to clamshell sleep/wake. I did open the laptop and toggle the setting for auto-brightness on the native display with no impact.

I feel like when waking from sleep in clamshell, the cinema display is recognized as the 'native' display and for whatever reason inherits the auto brightness setting, but doesn't expose that setting in the systems preferences pane to disable it.

This behavior is constant UNTIL I DISABLE THE BUTTONS ON THE DISPLAY under the 'options' tab. now it does let me set (and keep) the brightness in the system preference display panel (display tab). This also disables the buttons on my keyboard. When I re-enable the ability to adjust brightness like a normal person (from the display or from the keyboard) the problem returns.

I was genuinely surprised to see night shift working on the external display -- it doesn't work with my other (non-apple) displays, so I would bet that their attempt to be 'fancy' and include the 15 year old cinema displays in their new feature is a little... buggy.

i'm not really concerned with the cause, but would encourage you all to report it to apple so WE don't have to each come up with our own solutions, but it eventually is fixed for us.

i hope the disabling of the on-display brightness buttons helps you.

TL; DR

 

[zzz1991]

The problem is solved. I was helped by a guy on another web site. In BIOS, you need to disable the XMP profile of the RAM and make edits in DSDT in Method (_INI, 0, Serialized)

.........
was
If (_OSI ("Windows 2015"))
{
OSYS = 0x07DF
}
.........
become
If ((_OSI ("Darwin") || _OSI ("Windows 2015")))
{
OSYS = 0x07DF
}

 

[haller]

The problem is solved. I was helped by a guy on another web site. In BIOS, you need to disable the XMP profile of the RAM and make edits in DSDT in Method (_INI, 0, Serialized)

I'm still struggling to fix this. Ho do I implement it in clover? do I need to patch my DSDT.aml file? I've never done that, what tool would I need?

 

[zzz1991]

I'm still struggling to fix this. Ho do I implement it in clover? do I need to patch my DSDT.aml file? I've never done that, what tool would I need?

This is not implemented in clover. You need to edit DSDT (with Plistedit pro for example). Without this, I do not know how to fix backlight control.

 

[PencilNotPen]

The problem is solved. I was helped by a guy on another web site. In BIOS, you need to disable the XMP profile of the RAM and make edits in DSDT in Method (_INI, 0, Serialized)

.........
was
If (_OSI ("Windows 2015"))
{
OSYS = 0x07DF
}
.........
become
If ((_OSI ("Darwin") || _OSI ("Windows 2015")))
{
OSYS = 0x07DF
}

Thanks for the solve, I plan to try it out. I have the same issue with Apple Cinema Display 30" and inability to change brightness when waking from sleep. Also replaced 660 for RX 580. Could you give a few more details about how to create the DSDT with the edits above, if it cannot be done with Clover Configurator please? (Or perhaps direct me to the post where you received the help?) Also, is disabling XMP for the RAM completely necessary, or is there some workaround? It seems a shame to have to slow the RAM just to get this to work.

Many thanks!

 

[zzz1991]

Thanks for the solve, I plan to try it out. I have the same issue with Apple Cinema Display 30" and inability to change brightness when waking from sleep. Also replaced 660 for RX 580. Could you give a few more details about how to create the DSDT with the edits above, if it cannot be done with Clover Configurator please? (Or perhaps direct me to the post where you received the help?) Also, is disabling XMP for the RAM completely necessary, or is there some workaround? It seems a shame to have to slow the RAM just to get this to work.

Many thanks!

I switched from Clover to OpenCore. Now I don't have these problem. For my config, DSDT is not needed, so I don't use it. No problem with screen brightness after sleep. Oh yes, I fixed Intel integrated graphics differently (I have UHD630 + vega64) through AAPL, ig-platform-id, it may also play a role. On clover, it seems like this. At the bottom left you need to add the line PciRoot..... and on the right aapl ig platform-id (you need to find for your processor). Other kexts, patches for the old Intel graphics fix must be removed (lilu and green must be present). If everything is done correctly in the system settings, only the Radion graphics will be displayed (as in real Macs). And in Intel power gadget Intel graphics will be displayed and its frequency will change, for example, when watching YouTube videos

 

[zzz1991]

Thanks for the solve, I plan to try it out. I have the same issue with Apple Cinema Display 30" and inability to change brightness when waking from sleep. Also replaced 660 for RX 580. Could you give a few more details about how to create the DSDT with the edits above, if it cannot be done with Clover Configurator please? (Or perhaps direct me to the post where you received the help?) Also, is disabling XMP for the RAM completely necessary, or is there some workaround? It seems a shame to have to slow the RAM just to get this to work.

Many thanks!

I just now finally understood what causes the problems with Apple Cinema Display. The problem turned out to be XMP profile of the RAM. It must be disabled in the BIOS settings. On OC or Clover, without dsdt files, but with a disconnected XMP, everything works good.