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rockowitz
DDC communication failed for Display Port attached monitor
Hello
I'm using 2 monitors LG 24EB23. Both attached to an Radeon R9 290 using the amdgpu driver on an Arch linux with the latest kernel (4.10.8)
I can control the monitor attached via DVI with ddcutil. But not the one attached via DP
# ddcutil detect --verbose
Output level: Verbose
Reporting DDC data errors: false
Trace groups active: none
Force I2C slave address: false
Display 1
I2C bus: /dev/i2c-5
Supports DDC: true
I2C address 0x30 (EDID block#) present: true
I2C address 0x37 (DDC) present: true
I2C address 0x50 (EDID) present: true
/sys/bus/i2c/devices/i2c-5/name: AMDGPU i2c bit bus 0x95
EDID synopsis:
Mfg id: GSM
Model: 24EB23
Serial number: (disclosed)
Manufacture year: 2014
EDID version: 1.3
Product code: 0x59b4 (22964)
Extra descriptor: Unspecified
Video input definition: 0x80 - Digital Input
White x,y: 0.312, 0.329
Red x,y: 0.652, 0.335
Green x,y: 0.304, 0.633
Blue x,y: 0.152, 0.065
Extension blocks: 0
EDID hex dump:
+0 +4 +8 +c 0 4 8 c
+0000 00 ff ff ff ff ff ff 00 1e 6d b4 59 b4 9b 02 00 .........m.Y....
+0010 09 18 01 03 80 34 21 78 ea 3c 31 a7 55 4d a2 27 .....4!x.<1.UM.'
+0020 10 50 54 a5 4b 00 71 4f 81 00 81 80 81 8f 95 00 .PT.K.qO........
+0030 a9 40 b3 00 d1 c0 28 3c 80 a0 70 b0 23 40 30 20 .@....(<..p.#@0
+0040 36 00 08 4a 21 00 00 1a 00 00 00 fd 00 38 4b 1e 6..J!........8K.
+0050 53 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 32 S... .....2
+0060 34 45 42 32 33 0a 20 20 20 20 20 20 00 00 00 ff 4EB23. ....
+0070 00 0a 20 20 20 20 20 20 20 20 20 20 20 20 01 d4 .. ..
VCP version: 2.1
Controller mfg: Mstar
Firmware version: 1.1
Invalid display
I2C bus: /dev/i2c-8
Supports DDC: true
I2C address 0x30 (EDID block#) present: false
I2C address 0x37 (DDC) present: true
I2C address 0x50 (EDID) present: true
/sys/bus/i2c/devices/i2c-8/name: card0-DP-1
EDID synopsis:
Mfg id: GSM
Model: 24EB23
Serial number:
Manufacture year: 2013
EDID version: 1.4
Product code: 0x59b5 (22965)
Extra descriptor: Unspecified
Video input definition: 0xa5 - Digital Input(DisplayPort)
White x,y: 0.312, 0.329
Red x,y: 0.652, 0.335
Green x,y: 0.304, 0.633
Blue x,y: 0.152, 0.065
Extension blocks: 1
EDID hex dump:
+0 +4 +8 +c 0 4 8 c
+0000 00 ff ff ff ff ff ff 00 1e 6d b5 59 01 01 01 01 .........m.Y....
+0010 01 17 01 04 a5 34 21 78 fa 3c 31 a7 55 4d a2 27 .....4!x.<1.UM.'
+0020 10 50 54 21 08 00 71 40 81 c0 81 00 81 80 95 00 .PT!..q@........
+0030 a9 40 b3 00 d1 c0 28 3c 80 a0 70 b0 23 40 30 20 .@....(<..p.#@0
+0040 36 00 08 4a 21 00 00 1a 00 00 00 fd 00 38 3d 1e 6..J!........8=.
+0050 53 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 32 S... .....2
+0060 34 45 42 32 33 0a 20 20 20 20 20 20 00 00 00 ff 4EB23. ....
+0070 00 0a 20 20 20 20 20 20 20 20 20 20 20 20 01 d4 .. ..
DDC communication failed
Is DDC/CI enabled in the monitor's on-screen display?
(I've stripped the serial number from the first hex dump, the second was already empty)
Have you tried swapping the monitors? Though the monitors have the same model string, the EDIDs show that they are slightly different. Does the problem stay with the monitor, or with the DisplayPort connection?
Is DDC/CI enabled in the OSD?
Please run the command "ddcutil environment --verbose" and send the output as an attachment.
From ddcutil's perspective, there's no difference between a DisplayPort and non-DisplayPort connection. That the video driver emulates the I2C bus over the DisplayPort AUX channel should be transparent. However, given the newness of the amdgpu driver I wouldn't be surprised if there are issues. I have a RX280 card in a test system. I'll make a point of testing it with amdgpu/DisplayPort.
Sanford
On 04/05/2017 10:25 PM, Jan wrote:
Hello
I'm using 2 monitors LG 24EB23. Both attached to an Radeon R9 290 using the amdgpu driver on an Arch linux with the latest kernel (4.10.8)
I can control the monitor attached via DVI with ddcutil. But not the one attached via DP
|# ddcutil detect --verbose Output level: Verbose Reporting DDC data errors: false Trace groups active: none Force I2C slave address: false Display 1 I2C bus: /dev/i2c-5 Supports DDC: true I2C address 0x30 (EDID block#) present: true I2C address 0x37 (DDC) present: true I2C address 0x50 (EDID) present: true /sys/bus/i2c/devices/i2c-5/name: AMDGPU i2c bit bus 0x95 EDID synopsis: Mfg id: GSM Model: 24EB23 Serial number: (disclosed) Manufacture year: 2014 EDID version: 1.3 Product code: 0x59b4 (22964) Extra descriptor: Unspecified Video input definition: 0x80 - Digital Input White x,y: 0.312, 0.329 Red x,y: 0.652, 0.335 Green x,y: 0.304, 0.633 Blue x,y: 0.152, 0.065 Extension blocks: 0 EDID hex dump: +0 +4 +8 +c 0 4 8 c +0000 00 ff ff ff ff ff ff 00 1e 6d b4 59 b4 9b 02 00 .........m.Y.... +0010 09 18 01 03 80 34 21 78 ea 3c 31 a7 55 4d a2 27 .....4!x.<1.UM.' +0020 10 50 54 a5 4b 00 71 4f 81 00 81 80 81 8f 95 00 .PT.K.qO........ +0030 a9 40 b3 00 d1 c0 28 3c 80 a0 70 b0 23 40 30 20 .@....(<..p.#@0 +0040 36 00 08 4a 21 00 00 1a 00 00 00 fd 00 38 4b 1e 6..J!........8K. +0050 53 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 32 S... .....2 +0060 34 45 42 32 33 0a 20 20 20 20 20 20 00 00 00 ff 4EB23. .... +0070 00 0a 20 20 20 20 20 20 20 20 20 20 20 20 01 d4 .. .. VCP version: 2.1 Controller mfg: Mstar Firmware version: 1.1 Invalid display I2C bus: /dev/i2c-8 Supports DDC: true I2C address 0x30 (EDID block#) present: false I2C address 0x37 (DDC) present: true I2C address 0x50 (EDID) present: true /sys/bus/i2c/devices/i2c-8/name: card0-DP-1 EDID synopsis: Mfg id: GSM Model: 24EB23 Serial number: Manufacture year: 2013 EDID version: 1.4 Product code: 0x59b5 (22965) Extra descriptor: Unspecified Video input definition: 0xa5 - Digital Input(DisplayPort) White x,y: 0.312, 0.329 Red x,y: 0.652, 0.335 Green x,y: 0.304, 0.633 Blue x,y: 0.152, 0.065 Extension blocks: 1 EDID hex dump: +0 +4 +8 +c 0 4 8 c +0000 00 ff ff ff ff ff ff 00 1e 6d b5 59 01 01 01 01 .........m.Y.... +0010 01 17 01 04 a5 34 21 78 fa 3c 31 a7 55 4d a2 27 .....4!x.<1.UM.' +0020 10 50 54 21 08 00 71 40 81 c0 81 00 81 80 95 00 .PT!..q@........ +0030 a9 40 b3 00 d1 c0 28 3c 80 a0 70 b0 23 40 30 20 .@....(<..p.#@0 +0040 36 00 08 4a 21 00 00 1a 00 00 00 fd 00 38 3d 1e 6..J!........8=. +0050 53 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 32 S... .....2 +0060 34 45 42 32 33 0a 20 20 20 20 20 20 00 00 00 ff 4EB23. .... +0070 00 0a 20 20 20 20 20 20 20 20 20 20 20 20 01 d4 .. .. DDC communication failed Is DDC/CI enabled in the monitor's on-screen display? |
(I've stripped the serial number from the first hex dump, the second was already empty)
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I've not directly swapped the monitors due to a short DVI cable, but the problem stays with the DP connection (same cable, never had problems with it) If I attach the previous DVI-Monitor via DP, its manufacture year and EDID-version changes (2014->2013; 1.3->1.4) (I have rebooted the system to verify it)
I have no idea, how to enable DDC/CI in the OSD or if it can be disabled.
Also the EDID information for the DP monitor do not show up every time (see both attached files) ddcenv.txt ddcenv2.txt
please tell me, if I can provide further information.
Edit: The problem also exists under Windows 8.1 with the ScreenBright tool And the problem also exists if I attach the DP monitor to the integrated Intel i915 card (Sandy Bridge) I begin to think that there is a problem with the monitor itself and not with the video card.
On 04/06/2017 08:10 PM, Jan wrote:
I've not directly swapped the monitors due to a short DVI cable, but the problem stays with the DP connection (same cable, never had problems with it) If I attach the previous DVI-Monitor via DP, its manufacture year and EDID-version changes (2014->2013; 1.3->1.4) (I have rebooted the system to verify it
I have no idea, how to enable DDC/CI in the OSD or if it can be disabled.
I've looked in the user manual for your monitor, and it doesn't appear there's any setting to control DDC/CI, which is very unusual. The manual states the monitor is DDC2B compliant. DDC2B is an older iteration in the DDC family of specs, but it probably means the monitor supports DDC/CI.
Also the EDID information for the DP monitor do not show up every time (see both attached files) ddcenv.txt https://github.com/rockowitz/ddcutil/files/904201/ddcenv.txt ddcenv2.txt https://github.com/rockowitz/ddcutil/files/904202/ddcenv2.txt
please tell me, if I can provide further information.
Given the i2cdetect also reports unexpected data for the I2C device on DisplayPort, and the kind of failures observed, I'm pretty certain this is an issue of the I2C over DisplayPort Aux Channel implementation in the amdgpu driver, which is not surprising given that it's still under active development. If I can replicate the problem I'll file a bug report. Unfortunately there's not a spare DisplayPort monitor here, and it will take some rearrangement to free up one of the monitors with a DisplayPort connection for use on the test system, so that may take a few days.
Sanford
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I have a similar problem here with an secondary Acer XB270HU on DP (only has that as connectivity). Manual states DDC2B support, works great on Windows but on linux no EDID and no DDC. Primary screen (Samsung SA850, also over DP) works great, even with DDC controls for brightness etc.
When plugging in the Acer:
Aug 05 00:28:44 believe kernel: [drm:amdgpu_atombios_encoder_set_bios_scratch_regs] DFP2 connected
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0
Aug 05 00:28:44 believe kernel: [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:49:DP-2] probed modes :
Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 82:"1024x768" 60 65000 1024 1048 1184 1344 768 771 777 806 0x40 0xa
Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 79:"800x600" 60 40000 800 840 968 1056 600 601 605 628 0x40 0x5
Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 78:"800x600" 56 36000 800 824 896 1024 600 601 603 625 0x40 0x5
Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 80:"848x480" 60 33750 848 864 976 1088 480 486 494 517 0x40 0x5
Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 77:"640x480" 60 25175 640 656 752 800 480 490 492 525 0x40 0xa
I2C nack doesn't seem right. ddcutil returns: Failure getting EDID for /dev/i2c-9: status code=EREMOTEIO(-121): Remote I/O error but that makes sense if the kernel isn't able to set up I2C comms properly.
i2cdetect:
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: 50 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
Since it works fine on Windows 10 with the GTX980, I will take a stab at booting a livecd on it and see where that gets me. I can also try the onboard i915 with it, have done neither yet.
Edit: fwiw this is with 4.12.4 and amdgpu on a HD7850
Gerben,
Please run the following commands as root and send the output as an attachment. Without that output its hard for me to say much.
ddcutil environment --verbose
ls -ld /sys/class/drm/card*/card-/i2c
(The latter command will go into the next point release of ddcutil.)
Looking at the code for drm_dp_i2c_do_msg.c, the errors are coming from the I2C-over-aux related code. Normally I'd suggest trying a DVI or HDMI connection, but that isn't an option for you. The problem may be in the amdgpu driver.
If using the i915 driver, be aware that there are issues with DisplayPort there as well, particularly when using a docking station.
Sanford
On 08/04/2017 06:41 PM, Gerben Meijer wrote:
I have a similar problem here with an secondary Acer XB270HU on DP (only has that as connectivity). Manual states DDC2B support, works great on Windows but on linux no EDID and no DDC. Primary screen (Samsung SA850, also over DP) works great, even with DDC controls for brightness etc.
When plugging in the Acer:
|Aug 05 00:28:44 believe kernel: [drm:amdgpu_atombios_encoder_set_bios_scratch_regs] DFP2 connected Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_dp_i2c_do_msg] I2C nack (result=0, size=0 Aug 05 00:28:44 believe kernel: [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:49:DP-2] probed modes : Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 82:"1024x768" 60 65000 1024 1048 1184 1344 768 771 777 806 0x40 0xa Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 79:"800x600" 60 40000 800 840 968 1056 600 601 605 628 0x40 0x5 Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 78:"800x600" 56 36000 800 824 896 1024 600 601 603 625 0x40 0x5 Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 80:"848x480" 60 33750 848 864 976 1088 480 486 494 517 0x40 0x5 Aug 05 00:28:44 believe kernel: [drm:drm_mode_debug_printmodeline] Modeline 77:"640x480" 60 25175 640 656 752 800 480 490 492 525 0x40 0xa |
|I2C nack| doesn't seem right. ddcutil returns: |Failure getting EDID for /dev/i2c-9: status code=EREMOTEIO(-121): Remote I/O error| but that makes sense if the kernel isn't able to set up I2C comms properly.
i2cdetect:
|0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: 50 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- |
Since it works fine on Windows 10 with the GTX980, I will take a stab at booting a livecd on it and see where that gets me. I can also try the onboard i915 with it, have done neither yet.
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So here's the same monitor on a GTX980, Ubuntu 17.04 live:
Display 1
I2C bus: /dev/i2c-16
Supports DDC: true
EDID synopsis:
Mfg id: ACR
Model: XB270HU
Serial number: #ASOQgqYB8LDd
Model year : 2013
EDID version: 1.4
VCP version: 2.2
Invalid display
I2C bus: /dev/i2c-19
Supports DDC: false
EDID synopsis:
Mfg id: ACR
Model: XB270HU
Serial number: #ASOQgqYB8LDd
Model year : 2013
EDID version: 1.4
DDC communication failed
Clearly there is an EDID here since it's detected when plugged in this GTX980. And I even have ddccontrol working on i2c-16, which is nvkm-0000:01:00.0-aux-0009 I2C adapter - so clearly it's an issue with the aux code. e.g. ddcutil setvcp -b 16 10 50 sets brightness levels.
ddcutil env for the box with a gtx980 - acer on i2c-16 here as only monitor
ddcutil env for the box with a HD7850 - acer on i2c-9 here as second monitor, primary on i2c-8
So it's a mystery to me why it's not working on the radeon card; perhaps because this is a G-SYNC monitor and it's doing something non-standard?
Gerben,
Re the GTX980 report, the Acer monitor is connected on DP-3. What is strange is that it has 2 different I2C buses assigned, i2c-16 and i2c-19. I2C slave address x50 (EDID) works for both, so you can read the EDID on both I2C buses. However, I2C slave address x37 (DDC) is active only on I2c-16, so DDC communication works only on bus I2C-16. I have occasionally seen this double I2C bus assignment for DisplayPort monitors on my own system, and have no idea what triggers it. However, the bottom line for the GTX980 with the nouveau driver is that ddcutil works. It detects i2c-16 as valid, and i2c-19 as invalid.
Re "HD7878" report, I assume you meant HD7870. However, there's no link to the report. Is this the card you're using with the amdgpu driver? Or was the original report for another card.
For each relevant card/driver combination, please send the output of the following commands, run as root, as attachments:
ddcutil environment ---verbose
ddcutil detect --verbose
ls -ld /sys/class/drm/card*/card*/i2c*
(Note that the last command is corrected from my prior email, which contained an extraneous "-" in the command.
Sanford
On 08/04/2017 07:42 PM, Gerben Meijer wrote:
So here's the same monitor on a GTX980, Ubuntu 17.04 live:
|Display 1 I2C bus: /dev/i2c-16 Supports DDC: true EDID synopsis: Mfg id: ACR Model: XB270HU Serial number: #ASOQgqYB8LDd Model year : 2013 EDID version: 1.4 VCP version: 2.2 Invalid display I2C bus: /dev/i2c-19 Supports DDC: false EDID synopsis: Mfg id: ACR Model: XB270HU Serial number: #ASOQgqYB8LDd Model year : 2013 EDID version: 1.4 DDC communication failed |
Clearly there is an EDID here since it's detected when plugged in this GTX980. And I even have ddccontrol working on i2c-16, which is |nvkm-0000:01:00.0-aux-0009 I2C adapter| - so clearly it's an issue with the aux code. e.g. |ddcutil setvcp -b 16 10 50| sets brightness levels.
ddcutil env for the box with a gtx980 https://pastebin.com/xdTrCc6u
- acer on i2c-16 here as only monitor
ddcutil env for the box with a HD7878 - acer on i2c-9 here as second monitor, primary on i2c-8
So it's a mystery to me why it's not working on the radeon card; perhaps because this is a G-SYNC monitor and it's doing something non-standard?
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I assume you are reading the comments over email since I fixed the link shortly after commenting; in any case, attached the data through Github this time. I included an interrogate as well.
hd7850-card-i2c.txt hd7850-detect.txt hd7850-env.txt hd7850-interrogate.txt
gtx980-interrogate.txt gtx980-find-i2c.txt gtx980-env.txt gtx980-detect.txt
Note that these are 2 different machines with the same CPU model; the HD7850 machine is the dual monitor setup with Debian 9 and the GTX980 is windows box where I just use a Ubuntu 17.04 live boot.
I tested this also with just the Acer screen attached and with different DP cables but none of that had any effect. I am yet to try connecting the Acer to the onboard Intel DP.
Also, on the gtx980 with the Ubuntu live cd, there is no /sys/class/drm/card*/card*/i2c*; it looks almost as if all i2c devices are under the nouveau driver. I've attached a find /sys|grep i2c instead though can't say how useful that is; this may or may not be a kernel issue.
Gerben,
This pretty clearly is an amdgpu driver issue. Your HD7850 is a GCN 1.0 card, and support for these cards by the amdgpu driver is marginal. The logs show errors in function drm_dp_i2c_do_msg in drm driver file drm_do_helper.c, reflecting lower level failures.
FWIW, I took the time to refresh my testbed system that has a R9 280X (Radeon 7970), also GCN 1.0, with amdgpu and kernel 4.10, and it does work.
Is there some reason you're using the amdgpu driver? What happens if you use the stable radeon driver?
Additional comment interspersed.
Sanford
On 08/05/2017 12:19 PM, Gerben Meijer wrote:
I assume you are reading the comments over email since I fixed the link shortly after commenting; in any case, attached the data through Github this time. I included an interrogate as well.
hd7850-card-i2c.txt https://github.com/rockowitz/ddcutil/files/1202486/hd7850-card-i2c.txt hd7850-detect.txt https://github.com/rockowitz/ddcutil/files/1202487/hd7850-detect.txt hd7850-env.txt https://github.com/rockowitz/ddcutil/files/1202488/hd7850-env.txt hd7850-interrogate.txt https://github.com/rockowitz/ddcutil/files/1202489/hd7850-interrogate.txt
gtx980-interrogate.txt https://github.com/rockowitz/ddcutil/files/1202511/gtx980-interrogate.txt gtx980-find-i2c.txt https://github.com/rockowitz/ddcutil/files/1202510/gtx980-find-i2c.txt gtx980-env.txt https://github.com/rockowitz/ddcutil/files/1202512/gtx980-env.txt gtx980-detect.txt https://github.com/rockowitz/ddcutil/files/1202509/gtx980-detect.txt
Note that these are 2 different machines with the same CPU model; the HD7850 machine is the dual monitor setup with Debian 9 and the GTX980 is windows box where I just use a Ubuntu 17.04 live boot.
I tested this also with just the Acer screen attached and with different DP cables but none of that had any effect. I am yet to try connecting the Acer to the onboard Intel DP.
Also, on the gtx980 with the Ubuntu live cd, there is no /sys/class/drm/card*/card*/i2c*; it looks almost as if all i2c devices are under the nouveau driver. I've attached a find /sys|grep i2c instead though can't say how useful that is; this may or may not be a kernel issue.
This is as expected. The nouveau and nvidia drivers to not create i2c nodes under /sys/class/card*/card*.
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No particular reason for amdgpu, but the radeon driver yields the exact same thing. I've attached a new set of files with radeon driver; in this set you'll see that I turned on drm debugging, then unplugged and inserted the Acer. Look for 'I2C nack'.
hd7850-card-i2c-radeon.txt hd7850-interrogate-radeon.txt hd7850-env-radeon.txt hd7850-detect-radeon.txt
So it's pretty obviously an issue with both radeon and amdgpu failing to properly init the monitors I2C. I will try the screen on the Intel iGPU next.
Since it's clearly a kernel issue, do you know the best place to address this further? dri-users seems to be a dead list.
Thanks!
Gerben,
Looks like the XB270HU does something the drivers don't expect. Only a couple (feeble) suggestions:
- verify that DDC/CI is enabled in the OSD
- Since you have a Windows system, try installing softMCCS from EnTech.
They make I2C related chips, and softMCCS is their utility for testing I2C communication. It has excellent diagnostics.
As for mailing lists, I haven't great suggestions. Since the problem does occur on radeon, you might try posting there.
Finally, there's no need to be sending interrogate reports for this problem. Essentially, interrogate just wraps up detect --verbose, environment --verbose, and probe --verbose. probe examines monitor VCP features, which is meaningless if there's no DDC connectivity.
Regards, Sanford
On 08/07/2017 07:09 AM, Gerben Meijer wrote:
No particular reason for amdgpu, but the radeon driver yields the exact same thing. I've attached a new set of files with radeon driver; in this set you'll see that I turned on drm debugging, then unplugged and inserted the Acer. Look for 'I2C nack'.
hd7850-card-i2c-radeon.txt https://github.com/rockowitz/ddcutil/files/1204617/hd7850-card-i2c-radeon.txt hd7850-interrogate-radeon.txt https://github.com/rockowitz/ddcutil/files/1204616/hd7850-interrogate-radeon.txt hd7850-env-radeon.txt https://github.com/rockowitz/ddcutil/files/1204615/hd7850-env-radeon.txt hd7850-detect-radeon.txt https://github.com/rockowitz/ddcutil/files/1204618/hd7850-detect-radeon.txt
So it's pretty obviously an issue with both radeon and amdgpu failing to properly init the monitors I2C. I will try the screen on the Intel iGPU next.
Since it's clearly a kernel issue, do you know the best place to address this further? dri-users seems to be a dead list.
Thanks!
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The monitor does DDC/CI - it's enabled and cannot be turned off in the OSD. I've also attached it to intel iGPU, same problem (see interrogate). Also attached SoftMMCS report and log.
intel-card-i2c.txt intel-interrogate.txt softMCCS.txt ACR0408 softMCCS test report.txt
Since it happens with both Intel and Radeon/AMDGPU I guess I can try to work with intel-gfx team; if you have any further suggestions I'm all ears. Thanks :)
No additional suggestions, I'm afraid. Do keep me posted.
Sanford
On 08/07/2017 08:30 AM, Gerben Meijer wrote:
The monitor does DDC/CI - it's enabled and cannot be turned off in the OSD. I've also attached it to intel iGPU, same problem (see interrogate). Also attached SoftMMCS report and log.
intel-card-i2c.txt https://github.com/rockowitz/ddcutil/files/1204756/intel-card-i2c.txt intel-interrogate.txt https://github.com/rockowitz/ddcutil/files/1204755/intel-interrogate.txt softMCCS.txt https://github.com/rockowitz/ddcutil/files/1204761/softMCCS.txt ACR0408 softMCCS test report.txt https://github.com/rockowitz/ddcutil/files/1204760/ACR0408.softMCCS.test.report.txt
Since it happens with both Intel and Radeon/AMDGPU I guess I can try to work with intel-gfx team; if you have any further suggestions I'm all ears. Thanks :)
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I've gotten nowhere. Made a bugzilla bug for the intel-gfx team here: https://bugs.freedesktop.org/show_bug.cgi?id=102069 - I suggest to add to that thread if you get the bug on intel GPUs but not amd/nvidia gpus.
What is your hardware configuration? I2C-Over-Aux is an acknowledged problem area with the i915 driver (https://bugs.freedesktop.org/show_bug.cgi?id=100954), and other drivers also seem to have issues.
If you have ddcutil installed, please run "ddcutil env -v" and "ddcutil det -v" and send the output as attachments.
If you have i2c-tools installed, you can also run i2cdetect to see if slave addresses x50 and x37 are detected for any I2C device.
Sanford
On 03/01/2018 08:41 AM, t-animal wrote:
Any news on this? I'm experiencing similar problems.
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Yes, I'm using the i915 driver. However by now I've managed to get it to work, by using a display port to DVI adapter cable. I'm trying to switch inputs and the associated command does not support switching to DP input. This leads me to the suspicion that maybe the monitor itself is part of the problem. Still investigating.
Are you (t-animal) and Gerben Meijer one and the same, or is it just coincidence that there are multiple postings on this thread today?
Do you know if the monitor supports VCP feature x60 (Input Source)? One thing I've observed with feature x60 is that the observed values do not necessarily conform the the specs. If you can, manually set the monitor to the desired input and use "ddcutil getvcp 60" to see what the actual value is.
Sanford
On 03/01/2018 10:23 AM, t-animal wrote:
Yes, I'm using the i915 driver. However by now I've managed to get it to work, by using a display port to DVI adapter cable. I'm trying to switch inputs and the associated command does not support switching to DP input. This leads me to the suspicion that maybe the monitor itself is part of the problem. Still investigating.
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Nope, I'm not Gerben Meijer. Yes, it does support x60. That is exactly the feature I'm trying to use. However while the monitor has a D-SUB (VGA), DP and DVI Input ddutil lists these values when probing:
Feature: 60 (Input Source)
Values:
01: VGA-1
03: DVI-1
04: DVI-2
None of these values support switching to the DP input and funnily the monitor doesn't even have a secondary DVI input. So I'm guessing the firmware is screwed up or something...
Gerben,
I've taken a look at the interrogate logs you posted. It certainly does seem to isolate the problem to the i915 driver. Note that there are acknowledged issues with the i915 DP i2c-over-aux implementation - see the later comments on https://bugs.freedesktop.org/show_bug.cgi?id=100954.
There's a difference in the amdgpu vs nouveau logs that I find puzzling. When probing for features with the amdgpu driver, unsupported features are cleanly reported - i.e. the unsupported feature bit is set in a proper response packet. This is as per the DDC spec. With the nouveau driver, on the other hand, reading unsupported features fails because of retries exceeded. The only interpretation I can come up with (and it's vague handwaving) is that it takes longer for the monitor to respond to a request for an unsupported feature, and that the amdgpu driver is more forgiving.
Sanford
On 03/01/2018 09:47 AM, Gerben Meijer wrote:
I've gotten nowhere. Made a bugzilla bug for the intel-gfx team here: https://bugs.freedesktop.org/show_bug.cgi?id=102069 - I suggest to add to that thread if you get the bug on intel GPUs but not amd/nvidia gpus.
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Hello, I am using a radeon gpu and a DDC CI capable monitor (mitsubishi RDT232WLM). Unfortunately the test result is also "Invalid display" and "DDC communication failed". Posting the output of ddcutil environment --verbose and ddcutil detect --verbose: detect.txt environment.txt
I assume you're the same person as user magnesium who posted a similar query in AUR (https://aur.archlinux.org/packages/ddcutil/).
You're running a version of ddcutil (0.8.6) that's over a year old. The current version, 0.9.5, is in AUR. If you're actually using ddcutil, I suggest you upgrade. That said, I don't believe your problem is related to the ddcutil version.
Your monitor is found on bus /dev/i2c-1. Slave address x37 (DDC/CI) is not responding. Among the several ways that the environment command probes for displays, it calls external program i2cdetect (i2cdetect -y 1), and that program too shows no response.
I'm afraid I don't have any very good suggestions for you. The post on AUR indicates you've checked the DDC enabled setting in the OSD. You might try running as root, though I don't see why that would make a difference. You might also try using a different connector, though the specifications I've found, as well as the environment output, indicate there's no DisplayPort connector on this monitor and DisplayPort is the one connector that tends to show variation.
Sanford
On 3/4/19 10:39 AM, helionmelion wrote:
Hello, I am using a radeon gpu and a DDC CI capable monitor (mitsubishi RDT232WLM). Unfortunately the test result is also "Invalid display" and "DDC communication failed". Posting the output of ddcutil environment --verbose
I assume you're the same person as user magnesium who posted a similar query in AUR (https://aur.archlinux.org/packages/ddcutil/).
Yes, I am the same person.
You're running a version of ddcutil (0.8.6) that's over a year old. The current version, 0.9.5, is in AUR. If you're actually using ddcutil, I suggest you upgrade.
Upgrade done.
You might also try using a different connector, though the specifications I've found, as well as the environment output, indicate there's no DisplayPort connector on this monitor and DisplayPort is the one connector that tends to show variation.
This monitor and video card does not have Displayport, but tried switching conectors from HDMI to old DVI and... it worked! Now, the monitor is detected!! Success!!!
Seems the problems is with HDMI connector! @rockowitz Thank you very much!!! Live long to ddcutil.
I'm glad to hear that switching from the HDMI to DVI connector on the monitor resolved the problem, though I must admit that the suggestion was a long shot. In terms of circuitry, DVI and HDMI are essentially the same. DVI connections are often reported as HDMI, and vice-versa. What connectors were you using on the video card in each case?
Can I ask you run the interrogate command and send the output? I'll add a description of your monitors to www.ddcutil.com/monitor_notes.
Sanford
On 3/4/19 5:22 PM, helionmelion wrote:
I assume you're the same person as user magnesium who posted a similar query in AUR (https://aur.archlinux.org/packages/ddcutil/).Yes, I am the same person.
You're running a version of ddcutil (0.8.6) that's over a year old. The current version, 0.9.5, is in AUR. If you're actually using ddcutil, I suggest you upgrade.Upgrade done.
You might also try using a different connector, though the specifications I've found, as well as the environment output, indicate there's no DisplayPort connector on this monitor and DisplayPort is the one connector that tends to show variation.This monitor and video card does not have Displayport, but tried switching conectors from HDMI to old DVI and... it worked! Now, the monitor is detected!! Success!!!
env2.txt https://github.com/rockowitz/ddcutil/files/2928418/env2.txt detect2.txt https://github.com/rockowitz/ddcutil/files/2928419/detect2.txt
Seems the problems is with HDMI connector! @rockowitz https://github.com/rockowitz Thank you very much!!! Live long to ddcutil.
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In terms of circuitry, DVI and HDMI are essentially the same.
I didn't know that.
What connectors were you using on the video card in each case?
I'm using the same connectors on monitor and video card side. HDMI with HDMI, and DVI with DVI. No adapters of any kind.
Connecting both HDMI and DVI (but using DVI of course), the funcion loadvcp (profile) does not work.
[ia@sun ~] % sudo ddcutil loadvcp ddcnight [1][8:59:34]
Monitor not connected: RDT232WLM - 0Z247468AJ
So I have to disconnect HDMI permanently to use loadvcp.
Can I ask you run the interrogate command and send the output?
Of course. interrogateHDMIandDVI.txt interrogateDVIonly.txt interrogateHDMIonly.txt
Hoping this could help others. Thank you for your attention.
(Addendum) For the first time, I noted that OSD configurations for each connection is saved in a separate buffer, inside the monitor. Setting brightness and color for DVI does not interfere with HDMI saved config and vice versa. Perhaps could this be a clue.
You ran the interrogate command as user ia, not root, so lacked privileges to access the /dev/i2c devices. Please run it as root. Alternatively, you can create group i2c, assign the /dev/i2c devices to that group, grant RW access to the dev/i2c devices to members of that group, and assign user ia to the group. See the comments at the end of the (current) interrogate output, or page Device Permissions http://www.ddcutil/i2c_permissions
Sanford
On 3/5/19 7:14 AM, helionmelion wrote:
In terms of circuitry, DVI and HDMI are essentially the same.I didn't know that.
What connectors were you using on the video card in each case?I'm using the same connectors on monitor and video card side. HDMI with HDMI, and DVI with DVI. No adapters of any kind.
Connecting both HDMI and DVI (but using DVI of course), the funcion loadvcp (profile) does not work. |[ia@sun ~] % sudo ddcutil loadvcp ddcnight [1][8:59:34]| |Monitor not connected: RDT232WLM - 0Z247468AJ |
So I have to disconnect HDMI permanently to use loadvcp.
Can I ask you run the interrogate command and send the output?Of course. interrogateHDMIandDVI.txt https://github.com/rockowitz/ddcutil/files/2930822/interrogateHDMIandDVI.txt interrogateDVIonly.txt https://github.com/rockowitz/ddcutil/files/2930823/interrogateDVIonly.txt
Hoping this could help others. Thank you for your attention.
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You ran the interrogate command as user ia, not root, so lacked privileges to access the /dev/i2c devices. Please run it as root.
Here we go: ROOTinterrogateDVI.txt ROOTinterrogateHDMI.txt ROOTinterrogateHDMI+DVI.txt
Alternatively, you can create group i2c, assign the /dev/i2c devices to that group, grant RW access to the dev/i2c devices to members of that group, and assign user ia to the group. See the comments at the end of the (current) interrogate output, or page Device Permissions
I'll study about this and learn later Best Regards.
Thank you for sending the interrogate output. I have added an entry for the RDT232WLM to documentation page Notes on Specific Monitors http://www.ddcutil.com/monitor_notes
Sanford
On 3/6/19 11:08 AM, helionmelion wrote:
You ran the interrogate command as user ia, not root, so lacked privileges to access the /dev/i2c devices. Please run it as root.Here we go: ROOTinterrogateDVI.txt https://github.com/rockowitz/ddcutil/files/2937155/ROOTinterrogateDVI.txt ROOTinterrogateHDMI.txt https://github.com/rockowitz/ddcutil/files/2937156/ROOTinterrogateHDMI.txt ROOTinterrogateHDMI+DVI.txt https://github.com/rockowitz/ddcutil/files/2937157/ROOTinterrogateHDMI%2BDVI.txt
Alternatively, you can create group i2c, assign the /dev/i2c devices to that group, grant RW access to the dev/i2c devices to members of that group, and assign user ia to the group. See the comments at the end of the (current) interrogate output, or page Device PermissionsI'll study about this and learn later Best Regards.
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I have a similar issue as this, except for I am using (having trouble with) HDMI. My monitor is an ASUS VG248QE, DDC enabled in the OSD. It is also connected to a Windows 10 machine through an Nvidia GTX 780 GPU using Display Port, and DDC works there. However on Linux I am using Integrated AMD Vega Graphics with the amdgpu driver. More specifically the Ryzen 2400G, which uses Vega 11 graphics. Motherboard is a MSI Gaming Carbon Pro.
I'm using 0.9.5-1 of ddcutil on Arch Linux with the 5.0.5 Linux Kernel.
$> ddcutil detect --verbose
Output level: Verbose
Reporting DDC data errors: false
Trace groups active: none
Traced functions: none
Traced files: none
Force I2C slave address: false
User defined features: disabled
Invalid display
I2C bus: /dev/i2c-4
I2C address 0x50 (EDID) present: true
Is eDP device: false
/sys/bus/i2c/devices/i2c-4/name: AMDGPU DM i2c hw bus 0
EDID synopsis:
Mfg id: ACI
Model: VG248
Serial number: FALMQS138687
Manufacture year: 2015
EDID version: 1.3
Product code: 9381
Extra descriptor: Unspecified
Video input definition: 0x80 - Digital Input
Supported features:
DPMS standby
DPMS suspend
DPMS active-off
Digital display type: RGB 4:4:4
Standard sRGB color space: False
White x,y: 0.313, 0.329
Red x,y: 0.650, 0.329
Green x,y: 0.331, 0.622
Blue x,y: 0.151, 0.053
Extension blocks: 1
EDID source:
EDID hex dump:
+0 +4 +8 +c 0 4 8 c
+0000 00 ff ff ff ff ff ff 00 04 69 a5 24 01 01 01 01 .........i.$....
+0010 2c 19 01 03 80 35 1e 78 ea 9d e5 a6 54 54 9f 26 ,....5.x....TT.&
+0020 0d 50 54 b7 ef 00 71 4f 81 80 81 40 81 c0 81 00 .PT...qO...@....
+0030 95 00 b3 00 01 01 02 3a 80 18 71 38 2d 40 58 2c .......:..q8-@X,
+0040 45 00 13 2b 21 00 00 1e 00 00 00 fd 00 32 4c 1e E..+!........2L.
+0050 53 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 56 S... .....V
+0060 47 32 34 38 0a 20 20 20 20 20 20 20 00 00 00 ff G248. ....
+0070 00 46 41 4c 4d 51 53 31 33 38 36 38 37 0a 01 ad .FALMQS138687...
DDC communication failed
Is DDC/CI enabled in the monitor's on-screen display?
Please run "sudo ddcutil env --verbose" or "sudo ddcutil interrogate" and send the output as an attachment.
Sanford
On 5/10/19 8:22 PM, Eden Tyler-Moss wrote:
I have a similar issue as this, except for I am using HDMI to HDMI from the get go. My monitor is an ASUS VG248QE, DDC enabled in the OSD. It is also connected to a Windows 10 machine through an Nvidia GTX 780 GPU using Display Port, and DDC works there. However on Linux I am using Integrated AMD Vega Graphics with the |amdgpu| driver. More specifically the Ryzen 2400G, which uses Vega 11 graphics. Motherboard is a MSI Gaming Carbon Pro.
I'm using 0.9.5-1 of ddcutil on Arch Linux with the 5.0.5 Linux Kernel.
|$> ddcutil detect --verbose Output level: Verbose Reporting DDC data errors: false Trace groups active: none Traced functions: none Traced files: none Force I2C slave address: false User defined features: disabled Invalid display I2C bus: /dev/i2c-4 I2C address 0x50 (EDID) present: true Is eDP device: false /sys/bus/i2c/devices/i2c-4/name: AMDGPU DM i2c hw bus 0 EDID synopsis: Mfg id: ACI Model: VG248 Serial number: FALMQS138687 Manufacture year: 2015 EDID version: 1.3 Product code: 9381 Extra descriptor: Unspecified Video input definition: 0x80
- Digital Input Supported features: DPMS standby DPMS suspend DPMS active-off Digital display type: RGB 4:4:4 Standard sRGB color space: False White x,y: 0.313, 0.329 Red x,y: 0.650, 0.329 Green x,y: 0.331, 0.622 Blue x,y: 0.151, 0.053 Extension blocks: 1 EDID source: EDID hex dump: +0 +4 +8 +c 0 4 8 c +0000 00 ff ff ff ff ff ff 00 04 69 a5 24 01 01 01 01 .........i.$.... +0010 2c 19 01 03 80 35 1e 78 ea 9d e5 a6 54 54 9f 26 ,....5.x....TT.& +0020 0d 50 54 b7 ef 00 71 4f 81 80 81 40 81 c0 81 00 .PT...qO...@.... +0030 95 00 b3 00 01 01 02 3a 80 18 71 38 2d 40 58 2c .......:..q8-@X, +0040 45 00 13 2b 21 00 00 1e 00 00 00 fd 00 32 4c 1e E..+!........2L. +0050 53 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 56 S... .....V +0060 47 32 34 38 0a 20 20 20 20 20 20 20 00 00 00 ff G248. .... +0070 00 46 41 4c 4d 51 53 31 33 38 36 38 37 0a 01 ad .FALMQS138687... DDC communication failed Is DDC/CI enabled in the monitor's on-screen display? |
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