DDC brightness control for DisplayPort MST-attached displays on Linux

I have my displays on my GTX 1060 set up with DisplayPort MST on one of them (the Dell U2414H) to try to cut down on a few cables. This works, in general, but there is a frustrating issue that I have confirmed does not exist with the Nvidia Windows driver: there is no way to control the screen brightness with software. On Linux, it seems that this is generally done with directly interacting with the display over DDC (i2c) with tools such as ddcutil, which works fine for the two directly connected monitors, but the Nvidia Linux driver does not expose a /dev/i2c-N for this third, MST-attached, monitor, even though the monitor supports DDC, which makes it impossible to adjust this display.

Under Windows, it is possible to use the win32 SetMonitorBrightness function to set the physical brightness of all my monitors and adjustments using this API function are reflected in the monitor’s on-screen display brightness menu. At the Windows API level, there is no difference with one of the displays running over MST. Therefore, this appears to be a flaw with the Nvidia Linux driver specifically.

This issue has been reported before here: https://bbs.archlinux.org/viewtopic.php?id=227462

Interestingly, unlike what is reported in that thread, xset dpms force off does work on all the monitors.

I would really appreciate if it were fixed or an alternative brightness control mechanism offered, as it limits the usefulness of multi-monitor setups on Linux.

This has been observed on Nvidia driver version 460.32.03.

Logs of `ddcutil env -v` (LONG)
dev/linux - [master] » sudo ddcutil env -v
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

Performance and Retry Options:
   Deferred sleep enabled:                      false
   Sleep suppression (reduced sleeps) enabled:  false
   Dynamic sleep adjustment enabled:            false

The following tests probe the runtime environment using multiple overlapping methods.
   Current time (local): 2021-01-21 15:19:10 PST
   Current time (UTC):   2021-01-21 23:19:10
   Seconds since boot:   46790

*** Basic System Information ***

ddcutil version: 0.9.9

/proc/version:
   Linux version 5.10.8-arch1-1 (linux@archlinux) (gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.35.1) #1 SMP PREEMPT Sun, 17 Jan 2021 22:0
7:13 +0000

Architecture:     x86_64
Distributor id:   (null)
Release:          (null)
Found a known architecture

/proc/cmdline:
   initrd=\amd-ucode.img initrd=\initramfs-linux.img zfs=zroot/ROOT/default rw

Compiler information:
   C standard: 201710
   gcc compatible compiler:
      Compiler version: 10.1.0

Processor information as reported by lscpu:
   Architecture:                    x86_64
   CPU op-mode(s):                  32-bit, 64-bit
   Byte Order:                      Little Endian
   Address sizes:                   43 bits physical, 48 bits virtual
   CPU(s):                          24
   On-line CPU(s) list:             0-23
   Thread(s) per core:              2
   Core(s) per socket:              12
   Socket(s):                       1
   NUMA node(s):                    1
   Vendor ID:                       AuthenticAMD
   CPU family:                      23
   Model:                           113
   Model name:                      AMD Ryzen 9 3900X 12-Core Processor
   Stepping:                        0
   Frequency boost:                 enabled
   CPU MHz:                         2506.352
   CPU max MHz:                     3800.0000
   CPU min MHz:                     2200.0000
   BogoMIPS:                        7603.20
   Virtualization:                  AMD-V
   L1d cache:                       384 KiB
   L1i cache:                       384 KiB
   L2 cache:                        6 MiB
   L3 cache:                        64 MiB
   NUMA node0 CPU(s):               0-23
   Vulnerability Itlb multihit:     Not affected
   Vulnerability L1tf:              Not affected
   Vulnerability Mds:               Not affected
   Vulnerability Meltdown:          Not affected
   Vulnerability Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl and seccomp
   Vulnerability Spectre v1:        Mitigation; usercopy/swapgs barriers and __user pointer sanitization
   Vulnerability Spectre v2:        Mitigation; Full AMD retpoline, IBPB conditional, STIBP conditional, RSB filling
   Vulnerability Srbds:             Not affected
   Vulnerability Tsx async abort:   Not affected
   Flags:                           fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 h
t syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monito
r ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3
dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 hw_pstate sme ssbd mba
sev ibpb stibp vmmcall sev_es fsgsbase bmi1 avx2 smep bmi2 cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsa
ves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr rdpru wbnoinvd arat npt lbrv svm_lock nrip_save tsc_scal
e vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif umip rdpid overflow_recov succor smca

DMI Information from /sys/class/dmi/id:
   Motherboard vendor:       Micro-Star International Co., Ltd.
   Motherboard product name: MPG B550 GAMING PLUS (MS-7C56)
   System vendor:            Micro-Star International Co., Ltd.
   System product name:      MS-7C56
   Chassis vendor:           Micro-Star International Co., Ltd.
   Chassis type:             3 - Desktop

Byte order checks:
   Is big endian (local test):       false
   WORDS_BIGENDIAN macro (autoconf): not defined
   __BYTE_ORDER__ macro (gcc):       __ORDER_LITTLE_ENDIAN__

*** Primary Check 1: Identify video card and driver ***

Obtaining card and driver information from /sys...
Primary video controller at PCI address 0000:2b:00.0 (boot_vga flag is set)
   Device class:        x030000    VGA compatible controller
   Vendor:              x10de      NVIDIA Corporation
   Device:              x1c03      GP106 [GeForce GTX 1060 6GB]
   Subvendor/Subdevice: 1458/3716  Gigabyte Technology Co., Ltd
   Driver name:         nvidia
   Driver version:      460.32.03
   I2C device:          i2c-3      name: NVIDIA i2c adapter 1 at 2b:00.0
   I2C device:          i2c-8      name: NVIDIA i2c adapter 8 at 2b:00.0
   I2C device:          i2c-6      name: NVIDIA i2c adapter 6 at 2b:00.0
   I2C device:          i2c-4      name: NVIDIA i2c adapter 2 at 2b:00.0
   I2C device:          i2c-9      name: NVIDIA i2c adapter 9 at 2b:00.0
   I2C device:          i2c-7      name: NVIDIA i2c adapter 7 at 2b:00.0
   I2C device:          i2c-5      name: NVIDIA i2c adapter 4 at 2b:00.0

*** Primary Check 2: Check that /dev/i2c-* exist and writable ***

Current user: root (0)

Checking /dev/i2c-* devices...

Unless the system is using the AMD proprietary driver fglrx, devices /dev/i2c-*
must exist and the logged on user must have read/write permission for those
devices (or at least those devices associated with monitors).

Typically, this access is enabled by:
  - setting the group for /dev/i2c-* to i2c
  - setting group RW permissions for /dev/i2c-*
  - making the current user a member of group i2c

Alternatively, this can be enabled by just giving everyone RW permission
The following tests probe for these conditions.

Checking for /dev/i2c-* devices...
   crw------- 1 root root 89, 0 Jan 21 14:48 /dev/i2c-0
   crw------- 1 root root 89, 1 Jan 21 14:48 /dev/i2c-1
   crw------- 1 root root 89, 2 Jan 21 14:48 /dev/i2c-2
   crw------- 1 root root 89, 3 Jan 21 14:48 /dev/i2c-3
   crw------- 1 root root 89, 4 Jan 21 14:48 /dev/i2c-4
   crw------- 1 root root 89, 5 Jan 21 14:48 /dev/i2c-5
   crw------- 1 root root 89, 6 Jan 21 14:48 /dev/i2c-6
   crw------- 1 root root 89, 7 Jan 21 14:48 /dev/i2c-7
   crw------- 1 root root 89, 8 Jan 21 14:48 /dev/i2c-8
   crw------- 1 root root 89, 9 Jan 21 14:48 /dev/i2c-9

Current user (root) has RW access to all /dev/i2c-* devices.

Checking for group i2c...
   Group i2c does not exist

Looking for udev rules files that reference i2c:
   Checking rules directory /lib/udev/rules.d:
      /lib/udev/rules.d/60-autosuspend.rules:SUBSYSTEM=="i2c", ATTR{name}=="cyapa", \
      /lib/udev/rules.d/60-sensor.rules:SUBSYSTEM=="iio", KERNEL=="iio*", SUBSYSTEMS=="usb|i2c|platform", \
   Checking rules directory /run/udev/rules.d:
      grep: /run/udev/rules.d/*rules: No such file or directory
   Checking rules directory /etc/udev/rules.d:
      grep: /etc/udev/rules.d/*rules: No such file or directory

*** Primary Check 3: Check that module i2c_dev is loaded ***

Checking for module i2c_dev...
   Module i2c-dev is NOT built into kernel
   Loadable i2c-dev module found
   Module i2c_dev is loaded

Check that kernel module i2c_dev is being loaded by examining files where this would be specified...
   grep: /etc/modules: No such file or directory
   /etc/modules-load.d/i2c-dev.conf:i2c-dev
   grep: /run/modules-load.d/*conf: No such file or directory

Check for any references to i2c_dev in /etc/modprobe.d ...
   grep: /etc/modprobe.d/*conf: No such file or directory
   grep: /run/modprobe.d/*conf: No such file or directory

*** Primary Check 4: Driver specific checks ***

Performing driver specific checks...

Checking for special settings for proprietary Nvidia driver
(Needed for some newer Nvidia cards).
   grep: /etc/X11/xorg.conf: No such file or directory
   grep: /etc/X11/xorg.conf.d/*: No such file or directory

*** Additional probes ***

Scanning /proc/modules for driver environment...
   Found other loaded module:      i2c_dev
   Found video driver module:      nvidia
   Found other loaded module:      drm_kms_helper
   Found other loaded module:      i2c_piix4
   Loaded drm module depends on:   nvidia_drm,drm_kms_helper,

Testing if modules are loaded using /sys...
   Module amdgpu           is NOT loaded
   Module fbdev            is NOT loaded
   Module fglrx            is NOT loaded
   Module fturbo           is NOT loaded
   Module i915             is NOT loaded
   Module mgag200          is NOT loaded
   Module nvidia           is loaded
   Module nouveau          is NOT loaded
   Module radeon           is NOT loaded
   Module vboxvideo        is NOT loaded
   Module vc4              is NOT loaded
   Module drm              is loaded
   Module i2c_algo_bit     is NOT loaded
   Module i2c_dev          is loaded
   Module i2c_piix4        is loaded
   Module ddcci            is NOT loaded

Examining /sys/bus/i2c/devices...
   /sys/bus/i2c/devices/i2c-3/name:   NVIDIA i2c adapter 1 at 2b:00.0
   /sys/bus/i2c/devices/i2c-1/name:   SMBus PIIX4 adapter port 2 at 0b00
   /sys/bus/i2c/devices/i2c-8/name:   NVIDIA i2c adapter 8 at 2b:00.0
   /sys/bus/i2c/devices/i2c-6/name:   NVIDIA i2c adapter 6 at 2b:00.0
   /sys/bus/i2c/devices/i2c-4/name:   NVIDIA i2c adapter 2 at 2b:00.0
   /sys/bus/i2c/devices/i2c-2/name:   SMBus PIIX4 adapter port 1 at 0b20
   /sys/bus/i2c/devices/i2c-0/name:   SMBus PIIX4 adapter port 0 at 0b00
   /sys/bus/i2c/devices/i2c-9/name:   NVIDIA i2c adapter 9 at 2b:00.0
   /sys/bus/i2c/devices/i2c-7/name:   NVIDIA i2c adapter 7 at 2b:00.0
   /sys/bus/i2c/devices/i2c-5/name:   NVIDIA i2c adapter 4 at 2b:00.0

Examining /proc/driver/nvidia:
   /proc/driver/nvidia/version:
      NVRM version: NVIDIA UNIX x86_64 Kernel Module  460.32.03  Sun Dec 27 19:00:34 UTC 2020
      GCC version:  gcc version 10.2.0 (GCC)
   /proc/driver/nvidia/registry:
      Binary: ""
   /proc/driver/nvidia/params:
      ResmanDebugLevel: 4294967295
      RmLogonRC: 1
      ModifyDeviceFiles: 1
      DeviceFileUID: 0
      DeviceFileGID: 0
      DeviceFileMode: 438
      InitializeSystemMemoryAllocations: 1
      UsePageAttributeTable: 4294967295
      EnableMSI: 1
      RegisterForACPIEvents: 1
      EnablePCIeGen3: 0
      MemoryPoolSize: 0
      KMallocHeapMaxSize: 0
      VMallocHeapMaxSize: 0
      IgnoreMMIOCheck: 0
      TCEBypassMode: 0
      EnableStreamMemOPs: 0
      EnableBacklightHandler: 1
      EnableUserNUMAManagement: 1
      NvLinkDisable: 0
      RmProfilingAdminOnly: 1
      PreserveVideoMemoryAllocations: 0
      EnableS0ixPowerManagement: 0
      S0ixPowerManagementVideoMemoryThreshold: 256
      DynamicPowerManagement: 0
      DynamicPowerManagementVideoMemoryThreshold: 200
      RegisterPCIDriver: 1
      EnablePCIERelaxedOrderingMode: 0
      RegistryDwords: ""
      RegistryDwordsPerDevice: ""
      RmMsg: ""
      GpuBlacklist: ""
      TemporaryFilePath: ""
   PCI bus id: 0000:2b:00.0
   /proc/driver/nvidia/gpus/0000:2b:00.0/information:
      Model:             GeForce GTX 1060 6GB
      IRQ:               95
      GPU UUID:          GPU-6d3b9e03-e5a1-30c3-6a40-f874c9fa55bc
      Video BIOS:        86.06.0e.00.6d
      Bus Type:          PCIe
      DMA Size:          47 bits
      DMA Mask:          0x7fffffffffff
      Bus Location:      0000:2b:00.0
      Device Minor:      0
      Blacklisted:       No
   /proc/driver/nvidia/gpus/0000:2b:00.0/registry:
      Binary: ""

Examining I2C buses, as detected by I2C layer...
   Current time (local): 2021-01-21 15:19:10 PST
   Current time (UTC):   2021-01-21 23:19:10
   Seconds since boot:   46790

   Detected 7 non-ignorable I2C buses:

   Bus /dev/i2c-3 found:   true
   Bus /dev/i2c-3 probed:  true
   Bus accessible:          true
   Bus is eDP:              false
   Valid bus name checked:  true
   I2C bus has valid name:  true
   Address 0x37 present:    false
   Address 0x50 present:    false

   Bus /dev/i2c-4 found:   true
   Bus /dev/i2c-4 probed:  true
   Bus accessible:          true
   Bus is eDP:              false
   Valid bus name checked:  true
   I2C bus has valid name:  true
   Address 0x37 present:    false
   Address 0x50 present:    false

   Bus /dev/i2c-5 found:   true
   Bus /dev/i2c-5 probed:  true
   Bus accessible:          true
   Bus is eDP:              false
   Valid bus name checked:  true
   I2C bus has valid name:  true
   Address 0x37 present:    false
   Address 0x50 present:    false

   Bus /dev/i2c-6 found:   true
   Bus /dev/i2c-6 probed:  true
   Bus accessible:          true
   Bus is eDP:              false
   Valid bus name checked:  true
   I2C bus has valid name:  true
   Address 0x37 present:    false
   Address 0x50 present:    false

   Bus /dev/i2c-7 found:   true
   Bus /dev/i2c-7 probed:  true
   Bus accessible:          true
   Bus is eDP:              false
   Valid bus name checked:  true
   I2C bus has valid name:  true
   Address 0x37 present:    false
   Address 0x50 present:    false

   Bus /dev/i2c-8 found:   true
   Bus /dev/i2c-8 probed:  true
   Bus accessible:          true
   Bus is eDP:              false
   Valid bus name checked:  true
   I2C bus has valid name:  true
   Address 0x37 present:    true
   Address 0x50 present:    true
   EDID synopsis:
      Mfg id:           DEL
      Model:            DELL U2715H
      Serial number:    H7YCC4BS0BRL
      Manufacture year: 2014
      EDID version:     1.4
      Product code:     53349
      Binary sn:        809652812 (0x3042524c)
      Extra descriptor:
      Video input definition: 0xa5 - Digital Input (DisplayPort)
      Supported features:
         DPMS active-off
         Digital display type: RGB 4:4:4 + YCrCb 4:2:2
         Standard sRGB color space: True
      White x,y:        0.313, 0.329
      Red   x,y:        0.661, 0.332
      Green x,y:        0.302, 0.613
      Blue  x,y:        0.149, 0.060
      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 10 ac 65 d0 4c 52 42 30   ..........e.LRB0
      +0010   30 18 01 04 a5 3c 22 78 3e 44 55 a9 55 4d 9d 26   0....<"x>DU.UM.&
      +0020   0f 50 54 a5 4b 00 b3 00 d1 00 71 4f a9 40 81 80   .PT.K.....qO.@..
      +0030   77 80 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20   w.....V^....)P0
      +0040   35 00 55 50 21 00 00 1a 00 00 00 ff 00 48 37 59   5.UP!........H7Y
      +0050   43 43 34 42 53 30 42 52 4c 0a 00 00 00 fc 00 44   CC4BS0BRL......D
      +0060   45 4c 4c 20 55 32 37 31 35 48 0a 20 00 00 00 fd   ELL U2715H. ....
      +0070   00 38 56 1e 71 1e 01 0a 20 20 20 20 20 20 01 03   .8V.q...      ..

   Bus /dev/i2c-9 found:   true
   Bus /dev/i2c-9 probed:  true
   Bus accessible:          true
   Bus is eDP:              false
   Valid bus name checked:  true
   I2C bus has valid name:  true
   Address 0x37 present:    true
   Address 0x50 present:    true
   EDID synopsis:
      Mfg id:           DEL
      Model:            DELL U2515H
      Serial number:    FJYC769I0BBL
      Manufacture year: 2016
      EDID version:     1.4
      Product code:     53359
      Binary sn:        809648716 (0x3042424c)
      Extra descriptor:
      Video input definition: 0xa5 - Digital Input (DisplayPort)
      Supported features:
         DPMS active-off
         Digital display type: RGB 4:4:4 + YCrCb 4:2:2
         Standard sRGB color space: True
      White x,y:        0.313, 0.329
      Red   x,y:        0.661, 0.332
      Green x,y:        0.302, 0.613
      Blue  x,y:        0.149, 0.060
      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 10 ac 6f d0 4c 42 42 30   ..........o.LBB0
      +0010   25 1a 01 04 a5 37 1f 78 3e 44 55 a9 55 4d 9d 26   %....7.x>DU.UM.&
      +0020   0f 50 54 a5 4b 00 b3 00 d1 00 71 4f a9 40 81 80   .PT.K.....qO.@..
      +0030   77 80 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20   w.....V^....)P0
      +0040   35 00 29 37 21 00 00 1a 00 00 00 ff 00 46 4a 59   5.)7!........FJY
      +0050   43 37 36 39 49 30 42 42 4c 0a 00 00 00 fc 00 44   C769I0BBL......D
      +0060   45 4c 4c 20 55 32 35 31 35 48 0a 20 00 00 00 fd   ELL U2515H. ....
      +0070   00 38 56 1e 71 1e 01 0a 20 20 20 20 20 20 01 7d   .8V.q...      .}

xrandr connection report:

Checking for possibly conflicting programs...
   root      552519  1.2  0.0 267532  8324 ?        Ssl  15:16   0:01 /usr/libexec/ddccontrol/ddccontrol_service

Examining I2C buses using i2cdetect...
   Current time (local): 2021-01-21 15:19:10 PST
   Current time (UTC):   2021-01-21 23:19:10
   Seconds since boot:   46790

   Device /dev/i2c-0 is a SMBus or other ignorable device.  Skipping i2cdetect.

   Device /dev/i2c-1 is a SMBus or other ignorable device.  Skipping i2cdetect.

   Device /dev/i2c-2 is a SMBus or other ignorable device.  Skipping i2cdetect.

   Probing bus /dev/i2c-3 using command "i2cdetect -y 3"
           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00:                         -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- 48 -- -- -- -- -- -- --
      50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- --

   Probing bus /dev/i2c-4 using command "i2cdetect -y 4"
           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00:                         -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- --

   Probing bus /dev/i2c-5 using command "i2cdetect -y 5"
           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00:                         -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- --

   Probing bus /dev/i2c-6 using command "i2cdetect -y 6"
           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00:                         -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- --

   Probing bus /dev/i2c-7 using command "i2cdetect -y 7"
           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00:                         -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- --

   Probing bus /dev/i2c-8 using command "i2cdetect -y 8"
           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00:                         -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- 37 -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      50: 50 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- --

   Probing bus /dev/i2c-9 using command "i2cdetect -y 9"
           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00:                         -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- 37 -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      50: 50 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- --

Performing basic scan of I2C devices using local sysenv functions...
   Current time (local): 2021-01-21 15:19:14 PST
   Current time (UTC):   2021-01-21 23:19:14
   Seconds since boot:   46794

   Examining device /dev/i2c-0...
                           Device /dev/i2c-0 is a SMBus or other ignorable device.  Skipping.

   Examining device /dev/i2c-1...
                           Device /dev/i2c-1 is a SMBus or other ignorable device.  Skipping.

   Examining device /dev/i2c-2...
                           Device /dev/i2c-2 is a SMBus or other ignorable device.  Skipping.

   Examining device /dev/i2c-3...
      Functionality: I2C_FUNC_I2C, I2C_FUNC_SMBUS_QUICK, I2C_FUNC_SMBUS_READ_BYTE,
                     I2C_FUNC_SMBUS_WRITE_BYTE, I2C_FUNC_SMBUS_READ_BYTE_DATA,
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA, I2C_FUNC_SMBUS_READ_WORD_DATA,
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA, I2C_FUNC_SMBUS_READ_BLOCK_DATA,
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
      Unable to read EDID, psc=EIO(-5): Input/output error

      Trying simple VCP read of feature 0x10...
      Attempt 1 to read feature returned hard error: EIO(-5): Input/output error
      DDC communication failed.

   Examining device /dev/i2c-4...
      Functionality: I2C_FUNC_I2C, I2C_FUNC_SMBUS_QUICK, I2C_FUNC_SMBUS_READ_BYTE,
                     I2C_FUNC_SMBUS_WRITE_BYTE, I2C_FUNC_SMBUS_READ_BYTE_DATA,
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA, I2C_FUNC_SMBUS_READ_WORD_DATA,
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA, I2C_FUNC_SMBUS_READ_BLOCK_DATA,
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
      Unable to read EDID, psc=EIO(-5): Input/output error

      Trying simple VCP read of feature 0x10...
      Attempt 1 to read feature returned hard error: EIO(-5): Input/output error
      DDC communication failed.

   Examining device /dev/i2c-5...
      Functionality: I2C_FUNC_I2C, I2C_FUNC_SMBUS_QUICK, I2C_FUNC_SMBUS_READ_BYTE,
                     I2C_FUNC_SMBUS_WRITE_BYTE, I2C_FUNC_SMBUS_READ_BYTE_DATA,
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA, I2C_FUNC_SMBUS_READ_WORD_DATA,
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA, I2C_FUNC_SMBUS_READ_BLOCK_DATA,
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
      Unable to read EDID, psc=EIO(-5): Input/output error

      Trying simple VCP read of feature 0x10...
      Attempt 1 to read feature returned hard error: EIO(-5): Input/output error
      DDC communication failed.

   Examining device /dev/i2c-6...
      Functionality: I2C_FUNC_I2C, I2C_FUNC_SMBUS_QUICK, I2C_FUNC_SMBUS_READ_BYTE,
                     I2C_FUNC_SMBUS_WRITE_BYTE, I2C_FUNC_SMBUS_READ_BYTE_DATA,
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA, I2C_FUNC_SMBUS_READ_WORD_DATA,
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA, I2C_FUNC_SMBUS_READ_BLOCK_DATA,
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
      Unable to read EDID, psc=EIO(-5): Input/output error

      Trying simple VCP read of feature 0x10...
      Attempt 1 to read feature returned hard error: EIO(-5): Input/output error
      DDC communication failed.

   Examining device /dev/i2c-7...
      Functionality: I2C_FUNC_I2C, I2C_FUNC_SMBUS_QUICK, I2C_FUNC_SMBUS_READ_BYTE,
                     I2C_FUNC_SMBUS_WRITE_BYTE, I2C_FUNC_SMBUS_READ_BYTE_DATA,
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA, I2C_FUNC_SMBUS_READ_WORD_DATA,
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA, I2C_FUNC_SMBUS_READ_BLOCK_DATA,
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
      Unable to read EDID, psc=EIO(-5): Input/output error

      Trying simple VCP read of feature 0x10...
      Attempt 1 to read feature returned hard error: EIO(-5): Input/output error
      DDC communication failed.

   Examining device /dev/i2c-8...
      Functionality: I2C_FUNC_I2C, I2C_FUNC_SMBUS_QUICK, I2C_FUNC_SMBUS_READ_BYTE,
                     I2C_FUNC_SMBUS_WRITE_BYTE, I2C_FUNC_SMBUS_READ_BYTE_DATA,
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA, I2C_FUNC_SMBUS_READ_WORD_DATA,
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA, I2C_FUNC_SMBUS_READ_BLOCK_DATA,
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
      Raw EDID:
              +0          +4          +8          +c            0   4   8   c
      +0000   00 ff ff ff ff ff ff 00 10 ac 65 d0 4c 52 42 30   ..........e.LRB0
      +0010   30 18 01 04 a5 3c 22 78 3e 44 55 a9 55 4d 9d 26   0....<"x>DU.UM.&
      +0020   0f 50 54 a5 4b 00 b3 00 d1 00 71 4f a9 40 81 80   .PT.K.....qO.@..
      +0030   77 80 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20   w.....V^....)P0
      +0040   35 00 55 50 21 00 00 1a 00 00 00 ff 00 48 37 59   5.UP!........H7Y
      +0050   43 43 34 42 53 30 42 52 4c 0a 00 00 00 fc 00 44   CC4BS0BRL......D
      +0060   45 4c 4c 20 55 32 37 31 35 48 0a 20 00 00 00 fd   ELL U2715H. ....
      +0070   00 38 56 1e 71 1e 01 0a 20 20 20 20 20 20 01 03   .8V.q...      ..
      EDID synopsis:
         Mfg id:           DEL
         Model:            DELL U2715H
         Serial number:    H7YCC4BS0BRL
         Manufacture year: 2014
         EDID version:     1.4
         Product code:     53349
         Binary sn:        809652812 (0x3042524c)
         Extra descriptor:
         Video input definition: 0xa5 - Digital Input (DisplayPort)
         Supported features:
            DPMS active-off
            Digital display type: RGB 4:4:4 + YCrCb 4:2:2
            Standard sRGB color space: True
         White x,y:        0.313, 0.329
         Red   x,y:        0.661, 0.332
         Green x,y:        0.302, 0.613
         Blue  x,y:        0.149, 0.060
         Extension blocks: 1
      EDID source:

      Trying simple VCP read of feature 0x10...
      read() returned 6e 88 02 00 10 00 00 64 00 3c fc
      Attempt 1 to read feature succeeded.
      DDC communication succeeded

   Examining device /dev/i2c-9...
      Functionality: I2C_FUNC_I2C, I2C_FUNC_SMBUS_QUICK, I2C_FUNC_SMBUS_READ_BYTE,
                     I2C_FUNC_SMBUS_WRITE_BYTE, I2C_FUNC_SMBUS_READ_BYTE_DATA,
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA, I2C_FUNC_SMBUS_READ_WORD_DATA,
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA, I2C_FUNC_SMBUS_READ_BLOCK_DATA,
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
      Raw EDID:
              +0          +4          +8          +c            0   4   8   c
      +0000   00 ff ff ff ff ff ff 00 10 ac 6f d0 4c 42 42 30   ..........o.LBB0
      +0010   25 1a 01 04 a5 37 1f 78 3e 44 55 a9 55 4d 9d 26   %....7.x>DU.UM.&
      +0020   0f 50 54 a5 4b 00 b3 00 d1 00 71 4f a9 40 81 80   .PT.K.....qO.@..
      +0030   77 80 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20   w.....V^....)P0
      +0040   35 00 29 37 21 00 00 1a 00 00 00 ff 00 46 4a 59   5.)7!........FJY
      +0050   43 37 36 39 49 30 42 42 4c 0a 00 00 00 fc 00 44   C769I0BBL......D
      +0060   45 4c 4c 20 55 32 35 31 35 48 0a 20 00 00 00 fd   ELL U2515H. ....
      +0070   00 38 56 1e 71 1e 01 0a 20 20 20 20 20 20 01 7d   .8V.q...      .}
      EDID synopsis:
         Mfg id:           DEL
         Model:            DELL U2515H
         Serial number:    FJYC769I0BBL
         Manufacture year: 2016
         EDID version:     1.4
         Product code:     53359
         Binary sn:        809648716 (0x3042424c)
         Extra descriptor:
         Video input definition: 0xa5 - Digital Input (DisplayPort)
         Supported features:
            DPMS active-off
            Digital display type: RGB 4:4:4 + YCrCb 4:2:2
            Standard sRGB color space: True
         White x,y:        0.313, 0.329
         Red   x,y:        0.661, 0.332
         Green x,y:        0.302, 0.613
         Blue  x,y:        0.149, 0.060
         Extension blocks: 1
      EDID source:

      Trying simple VCP read of feature 0x10...
      read() returned 6e 88 02 00 10 00 00 64 00 3c fc
      Attempt 1 to read feature succeeded.
      DDC communication succeeded

EDIDs reported by X11 for connected xrandr outputs:
   xrandr output: DP-2.8
      Raw EDID:
              +0          +4          +8          +c            0   4   8   c
      +0000   00 ff ff ff ff ff ff 00 10 ac 65 d0 4c 52 42 30   ..........e.LRB0
      +0010   30 18 01 04 a5 3c 22 78 3e 44 55 a9 55 4d 9d 26   0....<"x>DU.UM.&
      +0020   0f 50 54 a5 4b 00 b3 00 d1 00 71 4f a9 40 81 80   .PT.K.....qO.@..
      +0030   77 80 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20   w.....V^....)P0
      +0040   35 00 55 50 21 00 00 1a 00 00 00 ff 00 48 37 59   5.UP!........H7Y
      +0050   43 43 34 42 53 30 42 52 4c 0a 00 00 00 fc 00 44   CC4BS0BRL......D
      +0060   45 4c 4c 20 55 32 37 31 35 48 0a 20 00 00 00 fd   ELL U2715H. ....
      +0070   00 38 56 1e 71 1e 01 0a 20 20 20 20 20 20 01 03   .8V.q...      ..
      EDID synopsis:
         Mfg id:           DEL
         Model:            DELL U2715H
         Serial number:    H7YCC4BS0BRL
         Manufacture year: 2014
         EDID version:     1.4
         Product code:     53349
         Binary sn:        809652812 (0x3042524c)
         Extra descriptor:
         Video input definition: 0xa5 - Digital Input (DisplayPort)
         Supported features:
            DPMS active-off
            Digital display type: RGB 4:4:4 + YCrCb 4:2:2
            Standard sRGB color space: True
         White x,y:        0.313, 0.329
         Red   x,y:        0.661, 0.332
         Green x,y:        0.302, 0.613
         Blue  x,y:        0.149, 0.060
         Extension blocks: 1
      EDID source:

   xrandr output: DP-2.1
      Raw EDID:
              +0          +4          +8          +c            0   4   8   c
      +0000   00 ff ff ff ff ff ff 00 10 ac a3 a0 4c 33 47 33   ............L3G3
      +0010   30 18 01 04 a5 35 1e 78 3e 7e 75 a7 55 52 9c 27   0....5.x>~u.UR.'
      +0020   0f 50 54 a5 4b 00 71 4f 81 80 a9 c0 a9 40 d1 c0   .PT.K.qO.....@..
      +0030   01 01 01 01 01 01 02 3a 80 18 71 38 2d 40 58 2c   .......:..q8-@X,
      +0040   45 00 0f 28 21 00 00 1e 00 00 00 ff 00 52 39 46   E..(!........R9F
      +0050   31 50 34 42 53 33 47 33 4c 0a 00 00 00 fc 00 44   1P4BS3G3L......D
      +0060   45 4c 4c 20 55 32 34 31 34 48 0a 20 00 00 00 fd   ELL U2414H. ....
      +0070   00 38 4c 1e 53 11 00 0a 20 20 20 20 20 20 01 df   .8L.S...      ..
      EDID synopsis:
         Mfg id:           DEL
         Model:            DELL U2414H
         Serial number:    R9F1P4BS3G3L
         Manufacture year: 2014
         EDID version:     1.4
         Product code:     41123
         Binary sn:        860304204 (0x3347334c)
         Extra descriptor:
         Video input definition: 0xa5 - Digital Input (DisplayPort)
         Supported features:
            DPMS active-off
            Digital display type: RGB 4:4:4 + YCrCb 4:2:2
            Standard sRGB color space: True
         White x,y:        0.313, 0.329
         Red   x,y:        0.653, 0.335
         Green x,y:        0.323, 0.611
         Blue  x,y:        0.153, 0.062
         Extension blocks: 1
      EDID source:
(query_x11                     ) EDID not found

   xrandr output: DP-4
      Raw EDID:
              +0          +4          +8          +c            0   4   8   c
      +0000   00 ff ff ff ff ff ff 00 10 ac 6f d0 4c 42 42 30   ..........o.LBB0
      +0010   25 1a 01 04 a5 37 1f 78 3e 44 55 a9 55 4d 9d 26   %....7.x>DU.UM.&
      +0020   0f 50 54 a5 4b 00 b3 00 d1 00 71 4f a9 40 81 80   .PT.K.....qO.@..
      +0030   77 80 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20   w.....V^....)P0
      +0040   35 00 29 37 21 00 00 1a 00 00 00 ff 00 46 4a 59   5.)7!........FJY
      +0050   43 37 36 39 49 30 42 42 4c 0a 00 00 00 fc 00 44   C769I0BBL......D
      +0060   45 4c 4c 20 55 32 35 31 35 48 0a 20 00 00 00 fd   ELL U2515H. ....
      +0070   00 38 56 1e 71 1e 01 0a 20 20 20 20 20 20 01 7d   .8V.q...      .}
      EDID synopsis:
         Mfg id:           DEL
         Model:            DELL U2515H
         Serial number:    FJYC769I0BBL
         Manufacture year: 2016
         EDID version:     1.4
         Product code:     53359
         Binary sn:        809648716 (0x3042424c)
         Extra descriptor:
         Video input definition: 0xa5 - Digital Input (DisplayPort)
         Supported features:
            DPMS active-off
            Digital display type: RGB 4:4:4 + YCrCb 4:2:2
            Standard sRGB color space: True
         White x,y:        0.313, 0.329
         Red   x,y:        0.661, 0.332
         Green x,y:        0.302, 0.613
         Blue  x,y:        0.149, 0.060
         Extension blocks: 1
      EDID source:

Probing I2C devices using udev, susbsystem i2c-dev...
   Current time (local): 2021-01-21 15:19:14 PST
   Current time (UTC):   2021-01-21 23:19:14
   Seconds since boot:   46794
Summary of udev I2C devices
   Subsystem   Sysname    Sysattr Name                        Devpath
   i2c-dev     i2c-0      SMBus PIIX4 adapter port 0 at 0b00  /devices/pci0000:00/0000:00:14.0/i2c-0/i2c-dev/i2c-0
   i2c-dev     i2c-1      SMBus PIIX4 adapter port 2 at 0b00  /devices/pci0000:00/0000:00:14.0/i2c-1/i2c-dev/i2c-1
   i2c-dev     i2c-2      SMBus PIIX4 adapter port 1 at 0b20  /devices/pci0000:00/0000:00:14.0/i2c-2/i2c-dev/i2c-2
   i2c-dev     i2c-3      NVIDIA i2c adapter 1 at 2b:00.0     /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-3/i2c-dev/i2c-3
   i2c-dev     i2c-4      NVIDIA i2c adapter 2 at 2b:00.0     /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-4/i2c-dev/i2c-4
   i2c-dev     i2c-5      NVIDIA i2c adapter 4 at 2b:00.0     /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-5/i2c-dev/i2c-5
   i2c-dev     i2c-6      NVIDIA i2c adapter 6 at 2b:00.0     /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-6/i2c-dev/i2c-6
   i2c-dev     i2c-7      NVIDIA i2c adapter 7 at 2b:00.0     /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-7/i2c-dev/i2c-7
   i2c-dev     i2c-8      NVIDIA i2c adapter 8 at 2b:00.0     /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-8/i2c-dev/i2c-8
   i2c-dev     i2c-9      NVIDIA i2c adapter 9 at 2b:00.0     /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-9/i2c-dev/i2c-9

Looking for udev devices with name attribute DPMST...
Summary of udev DPMST devices...
   No devices detected

amdgpu configuration parameters:


Examining configuration files...

DKMS modules:

Kernel I2C configuration settings:
   grep: /boot/config-5.10.8-arch1-1: No such file or directory

Kernel AMDGPU configuration settings:
   grep: /boot/config-5.10.8-arch1-1: No such file or directory


Examining system logs...
Current timestamps:
   Current time (local): 2021-01-21 15:19:14 PST
   Current time (UTC):   2021-01-21 23:19:14
   Seconds since boot:   46794

   Scanning dmesg output for I2C related entries...
   Executing command: dmesg
      [    0.682894] ACPI: Added _OSI(Linux-Dell-Video)
      [    1.563098] ata1.00: supports DRM functions and may not be fully accessible
      [    1.565922] ata1.00: supports DRM functions and may not be fully accessible
      [    2.972174] ata5.00: supports DRM functions and may not be fully accessible
      [    2.975094] ata5.00: supports DRM functions and may not be fully accessible
      [    4.029885] systemd[1]: Starting Load Kernel Module drm...
      [    4.054003] systemd[1]: modprobe@drm.service: Succeeded.
      [    4.054297] systemd[1]: Finished Load Kernel Module drm.
      [    4.054650] audit: type=1130 audit(1611224364.466:4): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=modprobe@drm comm="
systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
      [    4.054652] audit: type=1131 audit(1611224364.466:5): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=modprobe@drm comm="
systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
      [    4.477321] input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/input3
      [    4.477362] input: HDA NVidia HDMI/DP,pcm=7 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/input4
      [    4.477396] input: HDA NVidia HDMI/DP,pcm=8 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/input5
      [    4.477431] input: HDA NVidia HDMI/DP,pcm=9 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/input6
      [    4.477464] input: HDA NVidia HDMI/DP,pcm=10 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/input7
      [    4.477496] input: HDA NVidia HDMI/DP,pcm=11 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/input8
      [    4.477529] input: HDA NVidia HDMI/DP,pcm=12 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/input9
      [    5.152855] nvidia-nvlink: Nvlink Core is being initialized, major device number 237
      [    5.153303] nvidia 0000:2b:00.0: enabling device (0002 -> 0003)
      [    5.154162] nvidia 0000:2b:00.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=none:owns=none
      [    5.270907] NVRM: loading NVIDIA UNIX x86_64 Kernel Module  460.32.03  Sun Dec 27 19:00:34 UTC 2020
      [    5.453041] nvidia-modeset: Loading NVIDIA Kernel Mode Setting Driver for UNIX platforms  460.32.03  Sun Dec 27 18:51:11 UTC 2
020
      [    5.458449] [drm] [nvidia-drm] [GPU ID 0x00002b00] Loading driver
      [    5.458453] [drm] Initialized nvidia-drm 0.0.0 20160202 for 0000:2b:00.0 on minor 0

   Scanning journalctl output for I2C related entries...
   Executing command: journalctl --no-pager --boot
      Jan 21 02:19:24 tail-bot kernel: ACPI: Added _OSI(Linux-Dell-Video)
      Jan 21 02:19:24 tail-bot kernel: ata1.00: supports DRM functions and may not be fully accessible
      Jan 21 02:19:24 tail-bot kernel: ata1.00: supports DRM functions and may not be fully accessible
      Jan 21 02:19:24 tail-bot kernel: ata5.00: supports DRM functions and may not be fully accessible
      Jan 21 02:19:24 tail-bot kernel: ata5.00: supports DRM functions and may not be fully accessible
      Jan 21 02:19:24 tail-bot systemd[1]: Starting Load Kernel Module drm...
      Jan 21 02:19:24 tail-bot systemd[1]: modprobe@drm.service: Succeeded.
      Jan 21 02:19:24 tail-bot systemd[1]: Finished Load Kernel Module drm.
      Jan 21 02:19:24 tail-bot kernel: audit: type=1130 audit(1611224364.466:4): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=m
odprobe@drm comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
      Jan 21 02:19:24 tail-bot kernel: audit: type=1131 audit(1611224364.466:5): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=m
odprobe@drm comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
      Jan 21 02:19:24 tail-bot audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=modprobe@drm comm="systemd"
 exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
      Jan 21 02:19:24 tail-bot audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=modprobe@drm comm="systemd"
exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
      Jan 21 02:19:24 tail-bot kernel: input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/inp
ut3
      Jan 21 02:19:24 tail-bot kernel: input: HDA NVidia HDMI/DP,pcm=7 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/inp
ut4
      Jan 21 02:19:24 tail-bot kernel: input: HDA NVidia HDMI/DP,pcm=8 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/inp
ut5
      Jan 21 02:19:24 tail-bot kernel: input: HDA NVidia HDMI/DP,pcm=9 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/inp
ut6
      Jan 21 02:19:24 tail-bot kernel: input: HDA NVidia HDMI/DP,pcm=10 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/in
put7
      Jan 21 02:19:24 tail-bot kernel: input: HDA NVidia HDMI/DP,pcm=11 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/in
put8
      Jan 21 02:19:24 tail-bot kernel: input: HDA NVidia HDMI/DP,pcm=12 as /devices/pci0000:00/0000:00:03.1/0000:2b:00.1/sound/card0/in
put9
      Jan 21 02:19:25 tail-bot kernel: nvidia-nvlink: Nvlink Core is being initialized, major device number 237
      Jan 21 02:19:25 tail-bot kernel: nvidia 0000:2b:00.0: enabling device (0002 -> 0003)
      Jan 21 02:19:25 tail-bot kernel: nvidia 0000:2b:00.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=none:owns=none
      Jan 21 02:19:25 tail-bot kernel: NVRM: loading NVIDIA UNIX x86_64 Kernel Module  460.32.03  Sun Dec 27 19:00:34 UTC 2020
      Jan 21 02:19:25 tail-bot kernel: nvidia-modeset: Loading NVIDIA Kernel Mode Setting Driver for UNIX platforms  460.32.03  Sun Dec
 27 18:51:11 UTC 2020
      Jan 21 02:19:25 tail-bot kernel: [drm] [nvidia-drm] [GPU ID 0x00002b00] Loading driver
      Jan 21 02:19:25 tail-bot kernel: [drm] Initialized nvidia-drm 0.0.0 20160202 for 0000:2b:00.0 on minor 0
      Jan 21 14:42:12 tail-bot dbus-daemon[1307]: [system] Activating via systemd: service name='org.freedesktop.home1' unit='dbus-org.
freedesktop.home1.service' requested by ':1.207' (uid=0 pid=505248 comm="sudo usermod -a -G video jade ")
      Jan 21 14:42:12 tail-bot sudo[505248]:     jade : TTY=pts/3 ; PWD=/home/jade/dev/linux ; USER=root ; COMMAND=/usr/bin/usermod -a
-G video jade
      Jan 21 14:42:12 tail-bot usermod[505249]: add 'jade' to group 'video'
      Jan 21 14:42:12 tail-bot usermod[505249]: add 'jade' to shadow group 'video'
      Jan 21 15:16:38 tail-bot ddccontrol_service[552539]: nvidia_open: mmap failed: Operation not permitted
      Jan 21 15:17:12 tail-bot ddccontrol_service[552539]: nvidia_open: mmap failed: Operation not permitted


   Scanning file: /var/log/Xorg.0.log
   Limiting output to first 200 relevant lines...
      [     7.324]      X.Org Video Driver: 24.1
      [     7.325] (II) xfree86: Adding drm device (/dev/dri/card0)
      [     7.326] (**) OutputClass "nvidia" ModulePath extended to "/usr/lib/nvidia/xorg,/usr/lib/xorg/modules,/usr/lib/xorg/modules"
      [     7.333] (II) Applying OutputClass "nvidia" to /dev/dri/card0
      [     7.333]      loading driver: nvidia
      [     7.333] (==) Matched nvidia as autoconfigured driver 0
      [     7.333] (==) Matched nouveau as autoconfigured driver 1
      [     7.333] (==) Matched fbdev as autoconfigured driver 4
      [     7.333] (II) LoadModule: "nvidia"
      [     7.333] (II) Loading /usr/lib/xorg/modules/drivers/nvidia_drv.so
      [     7.337] (II) Module nvidia: vendor="NVIDIA Corporation"
      [     7.337]      Module class: X.Org Video Driver
      [     7.338] (II) LoadModule: "nouveau"
      [     7.338] (WW) Warning, couldn't open module nouveau
      [     7.338] (EE) Failed to load module "nouveau" (module does not exist, 0)
      [     7.340]      Module class: X.Org Video Driver
      [     7.340]      ABI class: X.Org Video Driver, version 24.1
      [     7.340] (II) LoadModule: "fbdev"
      [     7.340] (WW) Warning, couldn't open module fbdev
      [     7.340] (EE) Failed to load module "fbdev" (module does not exist, 0)
      [     7.340] (II) NVIDIA dlloader X Driver  460.32.03  Sun Dec 27 18:56:00 UTC 2020
      [     7.340] (II) NVIDIA Unified Driver for all Supported NVIDIA GPUs
      [     7.344] (II) NVIDIA(0): Creating default Display subsection in Screen section
      [     7.344] (==) NVIDIA(0): Depth 24, (==) framebuffer bpp 32
      [     7.344] (==) NVIDIA(0): RGB weight 888
      [     7.344] (==) NVIDIA(0): Default visual is TrueColor
      [     7.344] (==) NVIDIA(0): Using gamma correction (1.0, 1.0, 1.0)
      [     7.344] (II) Applying OutputClass "nvidia" options to /dev/dri/card0
      [     7.344] (**) NVIDIA(0): Option "AllowEmptyInitialConfiguration"
      [     7.344] (**) NVIDIA(0): Enabling 2D acceleration
      [     7.344] (II) Loading sub module "glxserver_nvidia"
      [     7.344] (II) LoadModule: "glxserver_nvidia"
      [     7.344] (II) Loading /usr/lib/nvidia/xorg/libglxserver_nvidia.so
      [     7.381] (II) Module glxserver_nvidia: vendor="NVIDIA Corporation"
      [     7.382] (II) NVIDIA GLX Module  460.32.03  Sun Dec 27 18:53:34 UTC 2020
      [     7.383] (II) NVIDIA: The X server supports PRIME Render Offload.
      [     8.473] (--) NVIDIA(0): Valid display device(s) on GPU-0 at PCI:43:0:0
      [     8.474] (--) NVIDIA(0):     DFP-4.8
      [     8.474] (--) NVIDIA(0):     DFP-4.1
      [     8.474] (--) NVIDIA(0):     DFP-0
      [     8.474] (--) NVIDIA(0):     DFP-1
      [     8.474] (--) NVIDIA(0):     DFP-2
      [     8.474] (--) NVIDIA(0):     DFP-3
      [     8.474] (--) NVIDIA(0):     DFP-4
      [     8.474] (--) NVIDIA(0):     DFP-5
      [     8.474] (--) NVIDIA(0):     DFP-6 (boot)
      [     8.474] (--) NVIDIA(0):     DFP-7
      [     8.476] (II) NVIDIA(0): NVIDIA GPU GeForce GTX 1060 6GB (GP106-A) at PCI:43:0:0
      [     8.476] (II) NVIDIA(0):     (GPU-0)
      [     8.476] (--) NVIDIA(0): Memory: 6291456 kBytes
      [     8.476] (--) NVIDIA(0): VideoBIOS: 86.06.0e.00.6d
      [     8.476] (II) NVIDIA(0): Detected PCI Express Link width: 16X
      [     8.477] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): connected
      [     8.477] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): Internal DisplayPort
      [     8.477] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): GUID: 10DE9070-0000-0000-0067-F35400000070
      [     8.477] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): 1440.0 MHz maximum pixel clock
      [     8.477] (--) NVIDIA(GPU-0):
      [     8.481] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): connected
      [     8.481] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): Internal DisplayPort
      [     8.481] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): 1440.0 MHz maximum pixel clock
      [     8.481] (--) NVIDIA(GPU-0):
      [     8.482] (--) NVIDIA(GPU-0): DFP-0: disconnected
      [     8.482] (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
      [     8.482] (--) NVIDIA(GPU-0): DFP-0: 330.0 MHz maximum pixel clock
      [     8.482] (--) NVIDIA(GPU-0):
      [     8.482] (--) NVIDIA(GPU-0): DFP-1: disconnected
      [     8.482] (--) NVIDIA(GPU-0): DFP-1: Internal TMDS
      [     8.482] (--) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
      [     8.482] (--) NVIDIA(GPU-0):
      [     8.482] (--) NVIDIA(GPU-0): DFP-2: disconnected
      [     8.482] (--) NVIDIA(GPU-0): DFP-2: Internal DisplayPort
      [     8.482] (--) NVIDIA(GPU-0): DFP-2: 1440.0 MHz maximum pixel clock
      [     8.482] (--) NVIDIA(GPU-0):
      [     8.482] (--) NVIDIA(GPU-0): DFP-3: disconnected
      [     8.482] (--) NVIDIA(GPU-0): DFP-3: Internal TMDS
      [     8.482] (--) NVIDIA(GPU-0): DFP-3: 165.0 MHz maximum pixel clock
      [     8.482] (--) NVIDIA(GPU-0):
      [     8.482] (--) NVIDIA(GPU-0): DFP-4: disconnected
      [     8.482] (--) NVIDIA(GPU-0): DFP-4: Internal DisplayPort
      [     8.482] (--) NVIDIA(GPU-0): DFP-4: 1440.0 MHz maximum pixel clock
      [     8.482] (--) NVIDIA(GPU-0):
      [     8.484] (--) NVIDIA(GPU-0): DFP-5: disconnected
      [     8.484] (--) NVIDIA(GPU-0): DFP-5: Internal TMDS
      [     8.484] (--) NVIDIA(GPU-0): DFP-5: 165.0 MHz maximum pixel clock
      [     8.484] (--) NVIDIA(GPU-0):
      [     8.485] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): connected
      [     8.485] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): Internal DisplayPort
      [     8.485] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): 1440.0 MHz maximum pixel clock
      [     8.485] (--) NVIDIA(GPU-0):
      [     8.487] (--) NVIDIA(GPU-0): DFP-7: disconnected
      [     8.487] (--) NVIDIA(GPU-0): DFP-7: Internal TMDS
      [     8.487] (--) NVIDIA(GPU-0): DFP-7: 165.0 MHz maximum pixel clock
      [     8.487] (--) NVIDIA(GPU-0):
      [     8.573] (==) NVIDIA(0):
      [     8.573] (==) NVIDIA(0): No modes were requested; the default mode "nvidia-auto-select"
      [     8.573] (==) NVIDIA(0):     will be used as the requested mode.
      [     8.573] (==) NVIDIA(0):
      [     8.573] (II) NVIDIA(0): Validated MetaModes:
      [     8.573] (II) NVIDIA(0):
      [     8.573] (II) NVIDIA(0):     "DFP-6:nvidia-auto-select,DFP-4.1:nvidia-auto-select,DFP-4.8:nvidia-auto-select"
      [     8.573] (II) NVIDIA(0): Virtual screen size determined to be 7040 x 1440
      [     8.581] (--) NVIDIA(0): DPI set to (118, 117); computed from "UseEdidDpi" X config
      [     8.581] (--) NVIDIA(0):     option
      [     8.582] (II) NVIDIA: Using 24576.00 MB of virtual memory for indirect memory
      [     8.582] (II) NVIDIA:     access.
      [     8.584] (II) NVIDIA(0): ACPI: failed to connect to the ACPI event daemon; the daemon
      [     8.584] (II) NVIDIA(0):     may not be running or the "AcpidSocketPath" X
      [     8.584] (II) NVIDIA(0):     configuration option may not be set correctly.  When the
      [     8.584] (II) NVIDIA(0):     ACPI event daemon is available, the NVIDIA X driver will
      [     8.584] (II) NVIDIA(0):     try to use it to receive ACPI event notifications.  For
      [     8.584] (II) NVIDIA(0):     details, please see the "ConnectToAcpid" and
      [     8.584] (II) NVIDIA(0):     "AcpidSocketPath" X configuration options in Appendix B: X
      [     8.584] (II) NVIDIA(0):     Config Options in the README.
      [     8.607] (II) NVIDIA(0): Setting mode "DFP-6:nvidia-auto-select,DFP-4.1:nvidia-auto-select,DFP-4.8:nvidia-auto-select"
      [     9.100] (==) NVIDIA(0): Disabling shared memory pixmaps
      [     9.100] (==) NVIDIA(0): Backing store enabled
      [     9.100] (==) NVIDIA(0): Silken mouse disabled
      [     9.101] (==) NVIDIA(0): DPMS enabled
      [     9.102] (II) NVIDIA(0): [DRI2] Setup complete
      [     9.102] (II) NVIDIA(0): [DRI2]   VDPAU driver: nvidia
      [     9.107] (II) Initializing extension XVideo
      [     9.107] (II) Initializing extension XVideo-MotionCompensation
      [     9.472] (II) config/udev: Adding input device HDA NVidia HDMI/DP,pcm=3 (/dev/input/event3)
      [     9.472] (II) config/udev: Adding input device HDA NVidia HDMI/DP,pcm=7 (/dev/input/event4)
      [     9.472] (II) config/udev: Adding input device HDA NVidia HDMI/DP,pcm=8 (/dev/input/event5)
      [     9.473] (II) config/udev: Adding input device HDA NVidia HDMI/DP,pcm=9 (/dev/input/event6)
      [     9.473] (II) config/udev: Adding input device HDA NVidia HDMI/DP,pcm=10 (/dev/input/event7)
      [     9.473] (II) config/udev: Adding input device HDA NVidia HDMI/DP,pcm=11 (/dev/input/event8)
      [     9.474] (II) config/udev: Adding input device HDA NVidia HDMI/DP,pcm=12 (/dev/input/event9)
      [     9.746] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): connected
      [     9.746] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): Internal DisplayPort
      [     9.746] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): 1440.0 MHz maximum pixel clock
      [     9.746] (--) NVIDIA(GPU-0):
      [     9.747] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): connected
      [     9.747] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): Internal DisplayPort
      [     9.747] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): GUID: 10DE9070-0000-0000-0067-F35400000070
      [     9.747] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): 1440.0 MHz maximum pixel clock
      [     9.747] (--) NVIDIA(GPU-0):
      [     9.747] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): connected
      [     9.747] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): Internal DisplayPort
      [     9.747] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): 1440.0 MHz maximum pixel clock
      [     9.747] (--) NVIDIA(GPU-0):
      [    22.820] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): connected
      [    22.820] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): Internal DisplayPort
      [    22.821] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): GUID: 10DE9070-0000-0000-0067-F35400000070
      [    22.821] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): 1440.0 MHz maximum pixel clock
      [    22.821] (--) NVIDIA(GPU-0):
      [    22.821] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): connected
      [    22.821] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): Internal DisplayPort
      [    22.821] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): 1440.0 MHz maximum pixel clock
      [    22.821] (--) NVIDIA(GPU-0):
      [    22.821] (--) NVIDIA(GPU-0): DFP-0: disconnected
      [    22.821] (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
      [    22.821] (--) NVIDIA(GPU-0): DFP-0: 330.0 MHz maximum pixel clock
      [    22.821] (--) NVIDIA(GPU-0):
      [    22.821] (--) NVIDIA(GPU-0): DFP-1: disconnected
      [    22.821] (--) NVIDIA(GPU-0): DFP-1: Internal TMDS
      [    22.821] (--) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
      [    22.821] (--) NVIDIA(GPU-0):
      [    22.821] (--) NVIDIA(GPU-0): DFP-2: disconnected
      [    22.821] (--) NVIDIA(GPU-0): DFP-2: Internal DisplayPort
      [    22.821] (--) NVIDIA(GPU-0): DFP-2: 1440.0 MHz maximum pixel clock
      [    22.821] (--) NVIDIA(GPU-0):
      [    22.821] (--) NVIDIA(GPU-0): DFP-3: disconnected
      [    22.821] (--) NVIDIA(GPU-0): DFP-3: Internal TMDS
      [    22.821] (--) NVIDIA(GPU-0): DFP-3: 165.0 MHz maximum pixel clock
      [    22.821] (--) NVIDIA(GPU-0):
      [    22.821] (--) NVIDIA(GPU-0): DFP-4: disconnected
      [    22.821] (--) NVIDIA(GPU-0): DFP-4: Internal DisplayPort
      [    22.821] (--) NVIDIA(GPU-0): DFP-4: 1440.0 MHz maximum pixel clock
      [    22.821] (--) NVIDIA(GPU-0):
      [    22.823] (--) NVIDIA(GPU-0): DFP-5: disconnected
      [    22.823] (--) NVIDIA(GPU-0): DFP-5: Internal TMDS
      [    22.823] (--) NVIDIA(GPU-0): DFP-5: 165.0 MHz maximum pixel clock
      [    22.823] (--) NVIDIA(GPU-0):
      [    22.824] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): connected
      [    22.824] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): Internal DisplayPort
      [    22.824] (--) NVIDIA(GPU-0): DELL U2515H (DFP-6): 1440.0 MHz maximum pixel clock
      [    22.824] (--) NVIDIA(GPU-0):
      [    22.826] (--) NVIDIA(GPU-0): DFP-7: disconnected
      [    22.826] (--) NVIDIA(GPU-0): DFP-7: Internal TMDS
      [    22.826] (--) NVIDIA(GPU-0): DFP-7: 165.0 MHz maximum pixel clock
      [    22.826] (--) NVIDIA(GPU-0):
      [    25.103] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): connected
      [    25.104] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): Internal DisplayPort
      [    25.104] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): GUID: 10DE9070-0000-0000-0067-F35400000070
      [    25.104] (--) NVIDIA(GPU-0): DELL U2715H (DFP-4.8): 1440.0 MHz maximum pixel clock
      [    25.104] (--) NVIDIA(GPU-0):
      [    25.104] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): connected
      [    25.104] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): Internal DisplayPort
      [    25.104] (--) NVIDIA(GPU-0): DELL U2414H (DFP-4.1): 1440.0 MHz maximum pixel clock
      [    25.104] (--) NVIDIA(GPU-0):
      [    25.104] (--) NVIDIA(GPU-0): DFP-0: disconnected
      [    25.104] (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
      [    25.104] (--) NVIDIA(GPU-0): DFP-0: 330.0 MHz maximum pixel clock
      [    25.104] (--) NVIDIA(GPU-0):
      [    25.104] (--) NVIDIA(GPU-0): DFP-1: disconnected
      [    25.104] (--) NVIDIA(GPU-0): DFP-1: Internal TMDS
      [    25.104] (--) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
      [    25.104] (--) NVIDIA(GPU-0):

   File not found: /var/log/messages

   File not found: /var/log/kern.log

   File not found: /var/log/daemon.log

   File not found: /var/log/syslog


   Log Summary
      Log                             Checked   Found
      ===                             =======   =====
      dmesg                           true      true
      journalctl                      true      false
      /var/log/daemon.log             true      false
      /var/log/kern.log               true      false
      /var/log/messages               true      false
      /var/log/syslog                 true      false
      /var/log/Xorg.0.log             true      true

Probing connected monitors using libdrm...

   Checking Nvidia options to see if experimental kernel modesetting enabled:
   Executing command: modprobe -c | grep "^options nvidia"

   Checking libdrm version using pkg-config...
      2.4.104

   Has a DRM kernel driver been loaded? (drmAvailable()): true

   Probing device /dev/dri/card0...
      Open succeeded for device: /dev/dri/card0

      DRM driver version information:
         Version:     0.0.0
         Driver:      nvidia-drm
         Date:        20160202
         Description: NVIDIA DRM driver

      DRM library version: 1.3.0.

      DRM Busid:

      Device information:
         bustype:                0 - pci
         domain:bus:device.func: 0000:2b:00.0
         vendor    vid:pid:      0x10de:0x1c03
         subvendor vid:pid:      0x1458:0x3716
         revision id:            0x00a1

      Is a modesetting capable driver attached to bus id: pci:0000:2b:00.0?
      (calling drmCheckModesettingAvailable())
         Modesetting not supported (-ENOSYS)

      Retrieving DRM resources...
      Failure retrieving DRM resources, errno=EOPNOTSUPP(95): Operation not supported

Examining /sys/class/drm...
   Query file system for i2c nodes under /sys/class/drm/card*...
   ls: cannot access '/sys/class/drm/card*/card*/i2c*': No such file or directory

Device Identifier Cross Reference Report

   /dev/i2c busno:     8
      EDID: ...20200103  Mfg: DEL  Model: DELL U2715H    SN: H7YCC4BS0BRL
                         Product number: 53349, binary SN: 809652812
      XrandR output:      DP-2.8
      DRM connector:      (null)
      UDEV name:          NVIDIA i2c adapter 8 at 2b:00.0
      UDEV syspath:       /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-8/i2c-dev/i2c-8
      UDEV busno:         8
      sysfs drm path:     (null)
      sysfs drm I2C:      (null)
      sysfs drm busno:    Unknown
      ambiguous EDID:     false

   /dev/i2c busno:     9
      EDID: ...2020017D  Mfg: DEL  Model: DELL U2515H    SN: FJYC769I0BBL
                         Product number: 53359, binary SN: 809648716
      XrandR output:      DP-4
      DRM connector:      (null)
      UDEV name:          NVIDIA i2c adapter 9 at 2b:00.0
      UDEV syspath:       /devices/pci0000:00/0000:00:03.1/0000:2b:00.0/i2c-9/i2c-dev/i2c-9
      UDEV busno:         9
      sysfs drm path:     (null)
      sysfs drm I2C:      (null)
      sysfs drm busno:    Unknown
      ambiguous EDID:     false

Video related contents of /etc/modprobe.d
   grep: /etc/modprobe.d/*conf: No such file or directory

Env_Accumulator:
   architecture:                  x86_64
   distributor_id
   Drivers detected:              nvidia
   /dev/i2c device numbers:       0 1 2 3 4 5 6 7 8 9
   sysfs_i2c_devices_exist:       true
   /sys/bus/i2c device numbers:   0 1 2 3 4 5 6 7 8 9
   dev_i2c_devices_required:      true
   module_i2c_dev_needed:         true
   module_i2c_dev_builtin:        false
   loadable_i2c_dev_exists:       true
   i2c_dev_loaded_or_builtin:     true
   group_i2c_checked:             true
   group_i2c_exists:              false
   dev_i2c_common_group_name:     root
   all_dev_i2c_has_group_i2c:     false
   any_dev_i2c_has_group_i2c:     false
   all_dev_i2c_is_group_rw:       true
   any_dev_i2c_is_group_rw:       false
   cur_uname:                     root
   cur_uid:                       0
   cur_user_in_group_i2c:         false
   cur_user_any_devi2c_rw:        true
   cur_user_all_devi2c_rw:        true

Configuration suggestions:
   Current user has RW access to all /dev/i2c-N devices.
   Skipping further group and permission checks.