Cannot get display based on i2c bus number

[mikecflood]

Last known version this worked on is 2.2.5. Fails when compiled with 2.2.6, 2.2.7 or 2.2.8-dev. I get the following run time error message:

DDC_DISPLAY ddca_get_display_ref() returned -3020 (DDCRC_INVALID_DISPLAY): invalid display

build command:

autoreconf --force --install
./configure --enable-install-lib-only --enable-static
make

code I am running:

std::string name_ = "DDC_DISPLAY";
int bus_ = 2;
DDCA_Display_Handle dh_ = nullptr;

void open_display()
{
    DDCA_Status rc = DDCRC_OK;
    DDCA_Display_Identifier did = nullptr;
    DDCA_Display_Ref dref = nullptr;

    rc = ddca_init2("", DDCA_SYSLOG_ERROR, DDCA_INIT_OPTIONS_CLIENT_OPENED_SYSLOG, nullptr);
    if (rc != DDCRC_OK)
    {
        log_ddcutil_error("ddca_init2", rc);
        return;
    }

    ddca_reset_stats();

    rc = ddca_create_busno_display_identifier(bus_, &did);
    if (rc != DDCRC_OK)
    {
        log_ddcutil_error("ddca_create_busno_display_identifier", rc);
        return;
    }

    rc = ddca_get_display_ref(did, &dref);
    ddca_free_display_identifier(did);
    if (rc != DDCRC_OK)
    {
        log_ddcutil_error("ddca_get_display_ref", rc);
        return;
    }

    rc = ddca_open_display2(dref, false, &dh_);
    if (rc != 0)
    {
        log_ddcutil_error("ddca_open_display2", rc);
        return;
    }
}

void DDC::log_ddcutil_error
(
    const std::string& a_func,
    const DDCA_Status a_error_code,
    const DDCA_Vcp_Feature_Code feature_code
)
{
    qWarning().noquote().nospace()
        << name_
        << " " << a_func << "()"
        << " returned " << a_error_code
        << " (" << ddca_rc_name(a_error_code) << "): "
        << ddca_rc_desc(a_error_code)
        << " dh=" << ddca_dh_repr(dh_)
        << ", feature_code=" << feature_code
        << " - " << ddca_get_feature_name(feature_code);
}

I also tried using ddca_get_display_info_list2, but it too fails to find the display.

output: DDC_DISPLAY failed to find display bus: 2

This is the code using ddca_get_display_info_list2:

std::string name_ = "DDC_DISPLAY";
int bus_ = 2;
DDCA_Display_Handle dh_ = nullptr;

void open_display()
{
    DDCA_Status rc = DDCRC_OK;
    DDCA_Display_Identifier did = nullptr;
    DDCA_Display_Ref dref = nullptr;

    rc = ddca_init2("", DDCA_SYSLOG_ERROR, DDCA_INIT_OPTIONS_CLIENT_OPENED_SYSLOG, nullptr);
    if (rc != DDCRC_OK)
    {
        log_ddcutil_error("ddca_init2", rc);
        return;
    }

    ddca_reset_stats();

    ddca_get_display_info_list2(false, &disp_list);
    if (disp_list && disp_list->ct > 0)
    {
        for (int i=0; i < disp_list->ct; i++)
        {
            if (disp_list->info[i].path.path.i2c_busno == bus_)
            {
                dref = disp_list->info[i].dref;
                display_found = true;
                break;
            }
        }
    }

    if (disp_list)
    {
        ddca_free_display_info_list(disp_list);
    }

    if (!display_found)
    {
        std::cout << name_ << "failed to find display bus: " << bus_);
        return;
    }

    rc = ddca_open_display2(dref, false, &dh_);
    if (rc != 0)
    {
        log_ddcutil_error("ddca_open_display2", rc);
        return;
    }
}

void DDC::log_ddcutil_error
(
    const std::string& a_func,
    const DDCA_Status a_error_code,
    const DDCA_Vcp_Feature_Code feature_code
)
{
    std::cout
        << name_
        << " " << a_func << "()"
        << " returned " << a_error_code
        << " (" << ddca_rc_name(a_error_code) << "): "
        << ddca_rc_desc(a_error_code)
        << " dh=" << ddca_dh_repr(dh_)
        << ", feature_code=" << feature_code
        << " - " << ddca_get_feature_name(feature_code);
}

Build env:

libtoolize: putting auxiliary files in AC_CONFIG_AUX_DIR, 'config'.
libtoolize: copying file 'config/ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'm4'.
libtoolize: copying file 'm4/libtool.m4'
libtoolize: copying file 'm4/ltoptions.m4'
libtoolize: copying file 'm4/ltsugar.m4'
libtoolize: copying file 'm4/ltversion.m4'
libtoolize: copying file 'm4/lt~obsolete.m4'
configure.ac:116: installing 'config/ar-lib'
configure.ac:36: installing 'config/compile'
configure.ac:131: installing 'config/config.guess'
configure.ac:131: installing 'config/config.sub'
configure.ac:108: installing 'config/install-sh'
configure.ac:108: installing 'config/missing'
src/app_ddcutil/Makefile.am: installing 'config/depcomp'
checking for gcc... gcc
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configure: debug messages disabled
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configure: Checking configure command options... 
configure: lib...              enabled 
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configure: build-timestamp...  enabled 
configure: envcmds...          enabled (provisional)   
configure: usb...              enabled (provisional)   
configure: systemd...           enabled (provisional)   
configure: dbus...              enabled (provisional)   
configure: drm...              enabled (provisional)   
configure: watch-displays...   enabled (provisional)   
configure: x11...              enabled (provisional)   
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configure: --enable-install-lib-only forces --disable-envcmds 
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configure: systemd...             enabled  
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configure: dbus...             enabled  
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configure: drm...             enabled  
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checking for x11... yes
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configure: x11...             enabled  
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configure: USE_DOXYGEN not set
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checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating Makefile
config.status: creating src/Makefile
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config.status: creating src/usb_util/Makefile
config.status: creating src/base/Makefile
config.status: creating src/vcp/Makefile
config.status: creating src/dynvcp/Makefile
config.status: creating src/sysfs/Makefile
config.status: creating src/i2c/Makefile
config.status: creating src/usb/Makefile
config.status: creating src/ddc/Makefile
config.status: creating src/dw/Makefile
config.status: creating src/test/Makefile
config.status: creating src/cmdline/Makefile
config.status: creating src/app_sysenv/Makefile
config.status: creating src/app_ddcutil/Makefile
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config.status: creating src/sample_clients/Makefile
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config.status: creating src/public/ddcutil_macros.h
config.status: creating data/ddcutil.pc
config.status: creating config.h
config.status: executing depfiles commands
config.status: executing libtool commands

	ddcutil 2.2.7
	version suffix:   
	=============

	libtool version  	10:1:5

	prefix:                 /usr/local
	exec_prefix:            ${prefix}
	libexecdir:             ${exec_prefix}/libexec
	bindir:                 ${exec_prefix}/bin
	libdir:                 ${exec_prefix}/lib
	datarootdir:            ${prefix}/share
	datadir:                ${datarootdir}
	docdir:                 ${datarootdir}/doc/${PACKAGE_TARNAME}
	mandir:               	${datarootdir}/man
	includedir:             ${prefix}/include
	pkgconfigdir:           
	required_packages:       glib-2.0 >= 2.40 jansson >= 2.0 libacl

	enable_lib:             yes
	enable_install_lib_only yes
	enable_build_timestamp  yes
	enable_envcmds          no
	enable_udev             yes
	enable_usb:             yes
	enable_drm:             yes
	enable_dbus:            yes
	enable_systemd:         yes
	enable_watch_displays:  yes
	enable_x11:             yes
	enable_asan:            no
	enable_static_functions_visible:  no

	Developer-only options:
	enable_targetbsd:       no
	enable_doxygen:         no
	enable_failsim:         no
	include_testcases:      no

	compiler:               gcc
	CFLAGS:                 -g -O2
	CPPFLAGS:               
	LDFLAGS:

[rockowitz]

Please submit the output of the following commands;

ddcutil detect --verbose
ddcutil detect --disable-try-get-edid-from-sysfs --verbose
sudo ddcutil environment --verbose 

[mikecflood]

ddcutil detect --verbose

Nothing to read from /sys/class
Nothing to read from /sys/class
No /sys/bus/i2c buses that might be used for DDC/CI communication found.
No display adapters with i2c buses appear to exist.
Nothing to read from /sys/class
Nothing to read from /sys/class
No displays found.
Run "ddcutil environment" to check for system configuration problems.

ddcutil detect --disable-try-get-edid-from-sysfs --verbose

Nothing to read from /sys/class
Nothing to read from /sys/class
No /sys/bus/i2c buses that might be used for DDC/CI communication found.
No display adapters with i2c buses appear to exist.
Nothing to read from /sys/class
Nothing to read from /sys/class
No displays found.
Run "ddcutil environment" to check for system configuration problems.

ddcutil environment --verbose

Setting output level very-verbose...
Setting maximum retries...
Forcing --stats...
Forcing --disable-capabilities-cache...
Forcing --force-slave-address..
Forcing --disable-cross-instance-locking...
Dynamic sleep currently enabled, disabling...
The following tests probe the runtime environment using multiple overlapping methods.
Set environment variable SYSENV_QUICK_TEST or option --quickenv to skip some long-running tests.
Running command with root privileges
Nothing to read from /sys/class
Nothing to read from /sys/class
   Current time (local): 2026-08-31 20:23:11 EDT
   Current time (UTC):   2026-09-01 00:23:11
   Seconds since boot:   463383

General Build Options:
   BUILD_SHARED_LIB:        Defined
   ENABLE_ENVCMDS:          Defined
   ENABLE_FAILSIM:          Not defined
   ENABLE_UDEV:             Defined
   USE_X11:                 Not defined
   USE_LIBDRM:              Defined
   ENABLE_USB:              Not defined
   WITH_ASAN:               Not defined

Private Build Options:
   TARGET_LINUX:            Defined
   TARGET_BSD:              Not defined
   INCLUDE_TESTCASES:       Not defined
   STATIC:                  Not defined


*** Basic System Information ***

ddcutil version: 2.2.6

/proc/version:
   Linux version 6.18.29_p20260521-raspberrypi-v8 (root@fileserver) (gcc (Gentoo 15.2.1_p20260214 p5) 15.2.1 20260214, GNU ld (Gentoo 2.46.0 p1) 2.46.0) #1 SMP PREEMPT Sun May 31 12:48:38 EDT 2026

Architecture:     aarch64
Distributor id:   (null)
Release:          (null)
Found a known architecture

/proc/cmdline:
   coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_headphones=0 cgroup_disable=memory snd_bcm2835.enable_hdmi=0  vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000  systemd.gpt_auto=0 dwc_otg.lpm_enable=0 init=/init drive=/dev/mmcblk0p1,auto root=ramfs ram_only=true console=tty logo.nologo ntp_server=server1.perceptics TZ=EST5EDT os_version_url="http://av.perceptics/hmi/config/[IP]/os_version" boot_url="http://av.perceptics/hmi/os_image/pi-3b+_[VERSION]_boot.tar.gz" config_url="http://av.perceptics/hmi/config/00_default/config_640x480.txt" cmdline_url="http://av.perceptics/hmi/config/[IP]/cmdline.txt" squash_url="http://av.perceptics/hmi/os_image/pi-3b+_[VERSION]_hmi.squashfs" custom_files_url="http://av.perceptics/hmi/config/[IP]/custom-files.tar.bz2"

Compiler information:
   C standard: 202311
   gcc compatible compiler:
      Compiler version: 15.2.1

Processor information as reported by lscpu:
   Architecture:                            aarch64
   CPU op-mode(s):                          32-bit, 64-bit
   Byte Order:                              Little Endian
   CPU(s):                                  4
   On-line CPU(s) list:                     0-3
   Vendor ID:                               ARM
   Model name:                              Cortex-A53
   Model:                                   4
   Thread(s) per core:                      1
   Core(s) per cluster:                     4
   Socket(s):                               -
   Cluster(s):                              1
   Stepping:                                r0p4
   Frequency boost:                         disabled
   CPU(s) scaling MHz:                      89%
   CPU max MHz:                             1400.0000
   CPU min MHz:                             600.0000
   BogoMIPS:                                38.40
   Flags:                                   fp asimd evtstrm crc32 cpuid
   L1d cache:                               128 KiB (4 instances)
   L1i cache:                               128 KiB (4 instances)
   L2 cache:                                512 KiB (1 instance)
   NUMA node(s):                            1
   NUMA node0 CPU(s):                       0-3
   Vulnerability Gather data sampling:      Not affected
   Vulnerability Ghostwrite:                Not affected
   Vulnerability Indirect target selection: Not affected
   Vulnerability Itlb multihit:             Not affected
   Vulnerability L1tf:                      Not affected
   Vulnerability Mds:                       Not affected
   Vulnerability Meltdown:                  Not affected
   Vulnerability Mmio stale data:           Not affected
   Vulnerability Old microcode:             Not affected
   Vulnerability Reg file data sampling:    Not affected
   Vulnerability Retbleed:                  Not affected
   Vulnerability Spec rstack overflow:      Not affected
   Vulnerability Spec store bypass:         Not affected
   Vulnerability Spectre v1:                Mitigation; __user pointer sanitization
   Vulnerability Spectre v2:                Not affected
   Vulnerability Srbds:                     Not affected
   Vulnerability Tsa:                       Not affected
   Vulnerability Tsx async abort:           Not affected
   Vulnerability Vmscape:                   Not affected

Skipping dmidecode checks on architecture aarch64.

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...
Driver name:    vc4_v3d

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

Current user: root (0)

Checking /dev/i2c-* devices...

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, 2 Aug 26 11:40 /dev/i2c-2

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-ddcutil-i2c.rules:SUBSYSTEM=="i2c-dev", KERNEL=="i2c-[0-9]*", ATTRS{class}=="0x03*", TAG+="uaccess"
      /lib/udev/rules.d/60-input-id.rules:        IMPORT{builtin}="hwdb 'id-input:i2c:v$attr{id/vendor}p$attr{id/product}:name:$attr{name}:'", \
      /lib/udev/rules.d/60-persistent-input.rules:SUBSYSTEMS=="i2c", ENV{ID_BUS}="i2c"
      /lib/udev/rules.d/60-persistent-input.rules:# subsystems before (usb, platform, i2c) can be under pci so only set them if we still have no ID_BUS.
      /lib/udev/rules.d/60-persistent-input.rules:# allow empty class for platform, usb and i2c devices; platform supports only a single interface that way
      /lib/udev/rules.d/60-persistent-input.rules:SUBSYSTEMS=="usb|platform|i2c", KERNEL=="event*", ENV{.INPUT_CLASS}=="", ENV{ID_PATH}=="?*", \
      /lib/udev/rules.d/60-persistent-input.rules:SUBSYSTEMS=="usb|platform|i2c", KERNEL=="event*", ENV{.INPUT_CLASS}=="", ENV{ID_PATH_WITH_USB_REVISION}=="?*", \
      /lib/udev/rules.d/60-sensor.rules:SUBSYSTEM=="iio", KERNEL=="iio*", SUBSYSTEMS=="usb|i2c|platform", ATTR{label}!="", \
      /lib/udev/rules.d/60-sensor.rules:SUBSYSTEM=="iio", KERNEL=="iio*", SUBSYSTEMS=="usb|i2c|platform", \
      /lib/udev/rules.d/65-integration.rules:ENV{ID_BUS}=="acpi|platform|i8042|i2c|rmi|spi|pci", ENV{ID_INTEGRATION}="internal", GOTO="libinput_integration_compat"
   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 driver i2c_dev...
   sysfs reports module i2c_dev is loaded.
   Kernel module i2c-dev does not exist!
   Module i2c_dev is NOT built into the kernel
   Loadable i2c-dev module NOT 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
   grep: /run/modules-load.d/*conf: No such file or directory
   /usr/lib/modules-load.d/ddcutil.conf:i2c-dev

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

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

Performing driver specific checks...
No driver specific checks apply.

*** Additional probes ***

Examining /sys/bus/i2c/devices...
   /sys/bus/i2c/devices/i2c-2/name:   bcm2835 (i2c@7e805000)

Env_Accumulator:
   architecture:                  aarch64
   distributor_id                 
   Drivers detected:              vc4_v3d
   /dev/i2c device numbers:       2
   sysfs_i2c_devices_exist:       true
   /sys/bus/i2c device numbers:   2
   dev_i2c_devices_required:      true
   module_i2c_dev_needed:         true
   module_i2c_dev_builtin:        false
   loadable_i2c_dev_exists:       false
   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.



*** Additional checks for remote diagnosis ***

Disabling capabilities cache ...
Disabling dynamic sleep ...

*** Displays as reported by DETECT Command ***
   No displays found.
   Run "ddcutil environment" to check for system configuration problems.
*** Checking if modules are loaded or builtin... ***
   Kernel module amdgpu           not found
   Kernel module fbdev            not found
   Kernel module fglrx            not found
   Kernel module fturbo           not found
   Kernel module i915             not found
   Kernel module mgag200          not found
   Kernel module nvidia           not found
   Kernel module nouveau          not found
   Kernel module radeon           not found
   Kernel module vboxvideo        not found
   Kernel module vc4              not found
   Kernel module drm              not found
   Kernel module i2c_algo_bit     not found
   Kernel module i2c_dev          not found
   Kernel module i2c_piix4        not found
   Kernel module ddcci            not found

Scanning /proc/modules for driver environment...
   Found other loaded module:      i2c_bcm2835
   Found video driver module:      vc4
   Found other loaded module:      drm_client_lib
   Found other loaded module:      drm_exec
   Found other loaded module:      drm_display_helper
   Found other loaded module:      drm_dma_helper
   Found other loaded module:      drm_kms_helper
   Found other loaded module:      i2c_dev
   Loaded drm module depends on:   vc4,drm_client_lib,drm_exec,drm_display_helper,drm_dma_helper,drm_kms_helper,
   Found other loaded module:      drm_panel_orientation_quirks

Checking display manager environment variables...
   DISPLAY=(not set)
   WAYLAND_DISPLAY=(not set)
   XDG_SESSION_TYPE=(not set)

Examining I2C buses, as detected by I2C layer...
   Current time (local): 2026-08-31 20:23:12 EDT
   Current time (UTC):   2026-09-01 00:23:12
   Seconds since boot:   463383

   Detected 0 non-ignorable I2C buses:
      No buses


xrandr connection report:

Checking for possibly conflicting programs...


Examining I2C buses using i2cdetect... 
   Current time (local): 2026-08-31 20:23:12 EDT
   Current time (UTC):   2026-09-01 00:23:12
   Seconds since boot:   463383
Nothing to read from /sys/class
Nothing to read from /sys/class

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

Examining I2C buses using get-edid | parse-edid... 
   Current time (local): 2026-08-31 20:23:12 EDT
   Current time (UTC):   2026-09-01 00:23:12
   Seconds since boot:   463383
Nothing to read from /sys/class
Nothing to read from /sys/class

   Device /dev/i2c-2 is a SMBus or other ignorable device.  Skipping get-edid | parse-edid.

Testing EDID read alternatives...
   Current time (local): 2026-08-31 20:23:12 EDT
   Current time (UTC):   2026-09-01 00:23:12
   Seconds since boot:   463383

   Examining device /dev/i2c-2...
Nothing to read from /sys/class
Nothing to read from /sys/class
      Device /dev/i2c-2 is a SMBus or other ignorable device.  Skipping.

Performing alternative scans of I2C devices using local sysenv functions...
   Current time (local): 2026-08-31 20:23:12 EDT
   Current time (UTC):   2026-09-01 00:23:12
   Seconds since boot:   463383

   Examining device /dev/i2c-2...
Nothing to read from /sys/class
Nothing to read from /sys/class
      Device /dev/i2c-2 is a SMBus or other ignorable device.  Skipping.
*** Probe I2C devices using udev, susbsystem i2c-dev ***
   Current time (local): 2026-08-31 20:23:12 EDT
   Current time (UTC):   2026-09-01 00:23:12
   Seconds since boot:   463383

Summary of udev I2C devices
   Subsystem   Sysname    Sysattr Name                        Devpath
   i2c-dev     i2c-2      bcm2835 (i2c@7e805000)              /devices/platform/soc/3f805000.i2c/i2c-2/i2c-dev/i2c-2

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


Examining configuration files...
   Examining /boot/config.txt:
      grep: /boot/config.txt: No such file or directory

   Looking for blacklisted drivers in /etc/modprobe.d:
      /etc/modprobe.d/rpi.conf:#blacklist vc4
      /etc/modprobe.d/rpi.conf:blacklist vc_sm_cma
      /etc/modprobe.d/rpi.conf:blacklist bcm2835-isp
      /etc/modprobe.d/rpi.conf:blacklist bcm2835_codec
      /etc/modprobe.d/rpi.conf:blacklist bcm2835_v4l2
      /etc/modprobe.d/rpi.conf:blacklist fuse
      /etc/modprobe.d/rpi.conf:blacklist ipv6
      /etc/modprobe.d/rpi.conf:blacklist sdhci_iproc
      /etc/modprobe.d/rpi.conf:blacklist joydev
      /etc/modprobe.d/rpi.conf:blacklist brcmfmac
      /etc/modprobe.d/rpi.conf:blacklist uio_pdrv_genirq
      /etc/modprobe.d/rpi.conf:blacklist dm_mod
      /etc/modprobe.d/rpi.conf:blacklist hci_uart
      /etc/modprobe.d/rpi.conf:blacklist cfg80211
      /etc/modprobe.d/touchscreen.conf:### Beginning: blacklist usbtouchscreen ###
      /etc/modprobe.d/touchscreen.conf:blacklist usbtouchscreen
      /etc/modprobe.d/touchscreen.conf:blacklist hid-multitouch
      /etc/modprobe.d/touchscreen.conf:### End: blacklist usbtouchscreen ###

Examining system logs...
Current timestamps:
   Current time (local): 2026-08-31 20:23:12 EDT
   Current time (UTC):   2026-09-01 00:23:12
   Seconds since boot:   463384

   Scanning dmesg output for I2C related entries...
   Executing command: dmesg
      [   25.488653] systemd[1]: Starting Load Kernel Module drm...
      [   25.630512] i2c_dev: i2c /dev entries driver
      [   25.828170] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
      [   27.951526] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
      [   27.990632] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
      [   27.999182] rc rc0: vc4-hdmi as /devices/platform/soc/3f902000.hdmi/rc/rc0
      [   27.999392] input: vc4-hdmi as /devices/platform/soc/3f902000.hdmi/rc/rc0/input1
      [   28.038717] input: vc4-hdmi HDMI Jack as /devices/platform/soc/3f902000.hdmi/sound/card0/input2
      [   28.043168] vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
      [   28.043632] vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops [vc4])
      [   28.044047] vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops [vc4])
      [   28.044278] vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops [vc4])
      [   28.044539] vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops [vc4])
      [   28.047363] vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4])
      [   28.086727] [drm] Initialized vc4 0.0.0 for soc:gpu on minor 0
      [   28.181910] vc4-drm soc:gpu: [drm] fb0: vc4drmfb frame buffer device

   Scanning journalctl output for I2C related entries...
   Executing command: journalctl --no-pager --boot
      Aug 26 11:40:35 [hostname] systemd[1]: Starting Load Kernel Module drm...
      Aug 26 11:40:35 [hostname] kernel: i2c_dev: i2c /dev entries driver
      Aug 26 11:40:34 [hostname] systemd-modules-load[676]: Inserted module 'i2c_dev'
      Aug 26 11:40:35 [hostname] systemd-modules-load[676]: Inserted module 'vc4'
      Aug 26 11:40:35 [hostname] kernel: vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
      Aug 26 11:40:35 [hostname] systemd[1]: modprobe@drm.service: Deactivated successfully.
      Aug 26 11:40:35 [hostname] systemd[1]: Finished Load Kernel Module drm.
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: rc rc0: vc4-hdmi as /devices/platform/soc/3f902000.hdmi/rc/rc0
      Aug 26 11:40:37 [hostname] kernel: input: vc4-hdmi as /devices/platform/soc/3f902000.hdmi/rc/rc0/input1
      Aug 26 11:40:37 [hostname] kernel: input: vc4-hdmi HDMI Jack as /devices/platform/soc/3f902000.hdmi/sound/card0/input2
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4])
      Aug 26 11:40:37 [hostname] kernel: [drm] Initialized vc4 0.0.0 for soc:gpu on minor 0
      Aug 26 11:40:37 [hostname] kernel: vc4-drm soc:gpu: [drm] fb0: vc4drmfb frame buffer device
      Aug 26 11:40:38 [hostname] systemd-logind[911]: Watching system buttons on /dev/input/event1 (vc4-hdmi)
      Aug 26 11:40:39 [hostname] X[942]: (II) [PENMOUNT] Calibration data in EEPROM is enabled !
      Aug 26 11:40:42 [hostname] display_ctl[971]:      vc4-hdmi
      Aug 26 11:40:42 [hostname] display_ctl[971]:      vc4-hdmi
      Aug 27 11:42:49 [hostname] display_ctl[9450]:      vc4-hdmi
      Aug 27 11:42:49 [hostname] display_ctl[9450]:      vc4-hdmi
      Aug 27 11:44:53 [hostname] display_ctl[9495]:      vc4-hdmi
      Aug 27 11:44:53 [hostname] display_ctl[9495]:      vc4-hdmi
      Aug 27 13:33:35 [hostname] display_ctl[10184]:      vc4-hdmi
      Aug 27 13:33:35 [hostname] display_ctl[10184]:      vc4-hdmi
      Aug 27 14:08:37 [hostname] display_ctl[10424]:      vc4-hdmi
      Aug 27 14:08:37 [hostname] display_ctl[10424]:      vc4-hdmi
      Aug 27 14:40:11 [hostname] display_ctl[10645]:      vc4-hdmi
      Aug 27 14:40:11 [hostname] display_ctl[10645]:      vc4-hdmi
      Aug 27 18:32:19 [hostname] display_ctl[12223]:      vc4-hdmi
      Aug 27 18:32:19 [hostname] display_ctl[12223]:      vc4-hdmi
      Aug 27 20:28:59 [hostname] display_ctl[12942]:      vc4-hdmi
      Aug 27 20:28:59 [hostname] display_ctl[12942]:      vc4-hdmi
      Aug 27 21:00:47 [hostname] display_ctl[13165]:      vc4-hdmi
      Aug 27 21:00:47 [hostname] display_ctl[13165]:      vc4-hdmi
      Aug 28 09:48:57 [hostname] display_ctl[17673]:      vc4-hdmi
      Aug 28 09:48:57 [hostname] display_ctl[17673]:      vc4-hdmi
      Aug 28 10:34:31 [hostname] display_ctl[17995]:      vc4-hdmi
      Aug 28 10:34:31 [hostname] display_ctl[17995]:      vc4-hdmi
      Aug 28 11:07:26 [hostname] display_ctl[18224]:      vc4-hdmi
      Aug 28 11:07:26 [hostname] display_ctl[18224]:      vc4-hdmi
      Aug 28 13:25:06 [hostname] display_ctl[19022]:      vc4-hdmi
      Aug 28 13:25:06 [hostname] display_ctl[19022]:      vc4-hdmi
      Aug 28 13:57:24 [hostname] display_ctl[19246]:      vc4-hdmi
      Aug 28 13:57:24 [hostname] display_ctl[19246]:      vc4-hdmi
      Aug 28 14:05:06 [hostname] display_ctl[19326]:      vc4-hdmi
      Aug 28 14:05:06 [hostname] display_ctl[19326]:      vc4-hdmi
      Aug 28 15:08:56 [hostname] display_ctl[19737]:      vc4-hdmi
      Aug 28 15:08:56 [hostname] display_ctl[19737]:      vc4-hdmi
      Aug 28 15:41:45 [hostname] display_ctl[19975]:      vc4-hdmi
      Aug 28 15:41:45 [hostname] display_ctl[19975]:      vc4-hdmi
      Aug 28 15:42:08 [hostname] display_ctl[20015]:      vc4-hdmi
      Aug 28 15:42:08 [hostname] display_ctl[20015]:      vc4-hdmi
      Aug 28 16:17:20 [hostname] display_ctl[20261]:      vc4-hdmi
      Aug 28 16:17:20 [hostname] display_ctl[20261]:      vc4-hdmi
      Aug 28 16:44:41 [hostname] display_ctl[20451]:      vc4-hdmi
      Aug 28 16:44:41 [hostname] display_ctl[20451]:      vc4-hdmi
      Aug 28 16:45:48 [hostname] display_ctl[20499]:      vc4-hdmi
      Aug 28 16:45:48 [hostname] display_ctl[20499]:      vc4-hdmi
      Aug 28 16:47:32 [hostname] display_ctl[20551]:      vc4-hdmi
      Aug 28 16:47:32 [hostname] display_ctl[20551]:      vc4-hdmi
      Aug 28 18:03:17 [hostname] display_ctl[21215]:      vc4-hdmi
      Aug 28 18:03:17 [hostname] display_ctl[21215]:      vc4-hdmi
      Aug 28 18:35:32 [hostname] display_ctl[21440]:      vc4-hdmi
      Aug 28 18:35:32 [hostname] display_ctl[21440]:      vc4-hdmi
      Aug 29 15:01:39 [hostname] display_ctl[29272]:      vc4-hdmi
      Aug 29 15:01:39 [hostname] display_ctl[29272]:      vc4-hdmi
      Aug 29 15:13:18 [hostname] display_ctl[29422]:      vc4-hdmi
      Aug 29 15:13:18 [hostname] display_ctl[29422]:      vc4-hdmi


   Scanning file: /var/log/Xorg.0.log
File /var/log/Xorg.0.log is huge.  Examining only last 50000 lines
Error reading file /var/log/Xorg.0.log: Invalid argument
(probe_log                     ) Error calling file_get_last_lines(), rc = -22

   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             false     false 
      /var/log/kern.log               true      false 
      /var/log/messages               true      false 
      /var/log/syslog                 true      false 
      /var/log/Xorg.0.log             true      false 

*** Probing connected monitors using libdrm ***

   Checking libdrm version using pkg-config...

   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:      vc4
         Date:        0
         Description: Broadcom VC4 graphics

      DRM library version: 1.3.0.

      DRM Busid:  

      Device information:
         bustype:                2 - platform
         domain:bus:device.func: 732f:6f:63.47
         vendor    vid:pid:      0x9100:0x83f9
         subvendor vid:pid:      0x0055:0x0000
         revision id:            0x0091

      Is a modesetting capable driver attached to bus id: platform:732f:6f:63.47?
      (calling drmCheckModesettingAvailable())
         Invalid bus id (-EINVAL)

      drmIsMaster() returned 0
         i.e. IS NOT master

      Retrieving DRM resources...

      Scanning defined properties...
         Property  1:  EDID                 flags: 0x00000014 - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_BLOB
         Property  2:  DPMS                 flags: 0x00000008 - DRM_MODE_PROP_ENUM
            enum value: 0, enum name: On
            enum value: 1, enum name: Standby
            enum value: 2, enum name: Suspend
            enum value: 3, enum name: Off
         Property  3:  PATH                 flags: 0x00000014 - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_BLOB
         Property  4:  TILE                 flags: 0x00000014 - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_BLOB
         Property  5:  link-status          flags: 0x00000008 - DRM_MODE_PROP_ENUM
            enum value: 0, enum name: Good
            enum value: 1, enum name: Bad
         Property  6:  non-desktop          flags: 0x00000006 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_IMMUTABLE
         Property  7:  HDR_OUTPUT_METADATA  flags: 0x00000010 - DRM_MODE_PROP_BLOB
         Property  8:  type                 flags: 0x0000000c - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_ENUM
            enum value: 0, enum name: Overlay
            enum value: 1, enum name: Primary
            enum value: 2, enum name: Cursor
         Property  9:  SRC_X                flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 10:  SRC_Y                flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 11:  SRC_W                flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 12:  SRC_H                flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 13:  CRTC_X               flags: 0x80000080 - DRM_MODE_PROP_SIGNED_RANGE, DRM_MODE_PROP_ATOMIC
         Property 14:  CRTC_Y               flags: 0x80000080 - DRM_MODE_PROP_SIGNED_RANGE, DRM_MODE_PROP_ATOMIC
         Property 15:  CRTC_W               flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 16:  CRTC_H               flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 17:  FB_ID                flags: 0x80000040 - DRM_MODE_PROP_OBJECT, DRM_MODE_PROP_ATOMIC
         Property 18:  IN_FENCE_FD          flags: 0x80000080 - DRM_MODE_PROP_SIGNED_RANGE, DRM_MODE_PROP_ATOMIC
         Property 19:  OUT_FENCE_PTR        flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 20:  CRTC_ID              flags: 0x80000040 - DRM_MODE_PROP_OBJECT, DRM_MODE_PROP_ATOMIC
         Property 21:  FB_DAMAGE_CLIPS      flags: 0x80000010 - DRM_MODE_PROP_BLOB, DRM_MODE_PROP_ATOMIC
         Property 22:  ACTIVE               flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 23:  MODE_ID              flags: 0x80000010 - DRM_MODE_PROP_BLOB, DRM_MODE_PROP_ATOMIC
         Property 24:  VRR_ENABLED          flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 25:  DEGAMMA_LUT          flags: 0x00000010 - DRM_MODE_PROP_BLOB
         Property 26:  DEGAMMA_LUT_SIZE     flags: 0x00000006 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_IMMUTABLE
         Property 27:  CTM                  flags: 0x00000010 - DRM_MODE_PROP_BLOB
         Property 28:  GAMMA_LUT            flags: 0x00000010 - DRM_MODE_PROP_BLOB
         Property 29:  GAMMA_LUT_SIZE       flags: 0x00000006 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_IMMUTABLE
         Property 30:  BACKGROUND_COLOR     flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 31:  IN_FORMATS           flags: 0x00000014 - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_BLOB
         Property 32:  IN_FORMATS_ASYNC     flags: 0x00000014 - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_BLOB
         Property 33:  SIZE_HINTS           flags: 0x00000014 - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_BLOB
         Property 36:  max bpc              flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 37:  left margin          flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 38:  right margin         flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 39:  top margin           flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 40:  bottom margin        flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 41:  Colorspace           flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 42:  Broadcast RGB        flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 45:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 46:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 47:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 48:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 49:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 50:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 51:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 52:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 53:  zpos                 flags: 0x00000006 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_IMMUTABLE
         Property 57:  WRITEBACK_FB_ID      flags: 0x80000040 - DRM_MODE_PROP_OBJECT, DRM_MODE_PROP_ATOMIC
         Property 58:  WRITEBACK_PIXEL_FORMATS flags: 0x80000014 - DRM_MODE_PROP_IMMUTABLE, DRM_MODE_PROP_BLOB, DRM_MODE_PROP_ATOMIC
         Property 59:  WRITEBACK_OUT_FENCE_PTR flags: 0x80000002 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_ATOMIC
         Property 61:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 64:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 65:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 66:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 67:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 68:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 69:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 70:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 71:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 72:  zpos                 flags: 0x00000006 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_IMMUTABLE
         Property 76:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 77:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 78:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 79:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 80:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 81:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 82:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 83:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 84:  zpos                 flags: 0x00000006 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_IMMUTABLE
         Property 88:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 89:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 90:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 91:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 92:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 93:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 94:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 95:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 96:  zpos                 flags: 0x00000006 - DRM_MODE_PROP_RANGE, DRM_MODE_PROP_IMMUTABLE
         Property 100:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 101:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 102:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 103:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 104:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 105:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 106:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 107:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 108:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 111:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 112:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 113:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 114:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 115:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 116:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 117:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 118:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 119:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 122:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 123:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 124:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 125:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 126:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 127:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 128:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 129:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 130:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 133:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 134:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 135:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 136:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 137:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 138:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 139:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 140:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 141:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 144:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 145:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 146:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 147:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 148:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 149:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 150:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 151:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 152:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 155:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 156:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 157:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 158:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 159:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 160:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 161:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 162:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 163:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 166:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 167:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 168:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 169:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 170:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 171:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 172:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 173:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 174:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 177:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 178:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 179:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 180:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 181:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 182:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 183:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 184:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 185:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 188:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 189:  pixel blend mode     flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 190:  rotation             flags: 0x00000020 - DRM_MODE_PROP_BITMASK
         Property 191:  COLOR_ENCODING       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 192:  COLOR_RANGE          flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 193:  SCALING_FILTER       flags: 0x00000008 - DRM_MODE_PROP_ENUM
         Property 194:  CHROMA_SITING_H      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 195:  CHROMA_SITING_V      flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 196:  zpos                 flags: 0x00000002 - DRM_MODE_PROP_RANGE
         Property 199:  alpha                flags: 0x00000002 - DRM_MODE_PROP_RANGE

      Scanning connectors...
      connector_id:        35
         connector name       HDMI-1
         connector_type:      11 - HDMI
         connector_type_id:   1
         connection:          1 - connected
         encoder:             34
            encoder type (signal format): 2 - TDMS
         EDID property
            Raw property blob:
            blob id: 672
        +0          +4          +8          +c            0   4   8   c   
+0000   00 ff ff ff ff ff ff 00 1d 85 01 24 01 00 00 00   ...........$....
+0010   20 12 01 03 80 2b 1b 6d ef c5 c6 a3 57 4a 9c 23    ....+.m....WJ.#
+0020   12 4f 54 af ef 80 81 80 81 8f b3 00 a9 40 61 40   .OT..........@a@
+0030   01 01 01 01 01 01 4e 0c 80 a0 20 e0 2d 10 08 60   ......N... .-..`
+0040   22 00 06 44 21 00 00 18 00 00 00 10 00 00 0a 20   "..D!.......... 
+0050   20 20 20 20 20 20 20 20 20 20 00 00 00 10 00 00             ......
+0060   0a 20 20 20 20 20 20 20 20 20 20 20 00 00 00 fc   .           ....
+0070   00 4c 43 44 20 4d 4f 4e 49 54 4f 52 20 20 01 21   .LCD MONITOR  .!
+0080   02 03 22 71 4f 90 01 02 03 04 05 06 07 11 12 13   .."qO...........
+0090   14 15 16 1f 23 09 7f 07 83 01 00 00 65 03 0c 00   ....#.......e...
+00a0   10 00 02 3a 80 18 71 38 2d 40 58 2c 45 00 d7 40   ...:..q8-@X,E..@
+00b0   32 00 00 1e 01 1d 00 72 51 d0 1e 20 6e 28 55 00   2......rQ.. n(U.
+00c0   d7 40 32 00 00 1e 01 1d 80 18 71 1c 16 20 58 2c   .@2.......q.. X,
+00d0   25 00 d7 40 32 00 00 9e 00 00 00 00 00 00 00 00   %..@2...........
+00e0   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   ................
+00f0   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 bb   ................
            EDID synopsis:
               Mfg id:               GLE - AD electronics
               Model:                LCD MONITOR
               Product code:         9217  (0x2401)
               Serial number:        
               Binary serial number: 1 (0x00000001)
               Manufacture year:     2008,  Week: 32
               EDID version:         1.3
               Extra descriptor:        
               Video input definition:    0x80 - Digital Input
               Supported features:
                  DPMS standby
                  DPMS suspend
                  DPMS active-off
                  Digital display type: RGB 4:4:4 + YCrCb 4:4:4
                  Standard sRGB color space: False
               White x,y:        0.310, 0.330
               Red   x,y:        0.640, 0.340
               Green x,y:        0.290, 0.610
               Blue  x,y:        0.140, 0.070
               Extension blocks: 1
            EDID source: DRM
(probe_open_device_using_libdrm) Unexpected: EDID ...20200121 not found in device cross reference table
         DPMS property
            dpms value = 3 - Off
         link-status property
            link-status value = 0 - Good



   *** Examining /sys/class/drm ***

   Connector: card0-HDMI-A-1
      /sys/class/drm/card0-HDMI-A-1/enabled                                 =  enabled
      /sys/class/drm/card0-HDMI-A-1/status                                  =  connected
      /sys/class/drm/card0-HDMI-A-1/edid                                    :  Found
        +0          +4          +8          +c            0   4   8   c   
+0000   00 ff ff ff ff ff ff 00 1d 85 01 24 01 00 00 00   ...........$....
+0010   20 12 01 03 80 2b 1b 6d ef c5 c6 a3 57 4a 9c 23    ....+.m....WJ.#
+0020   12 4f 54 af ef 80 81 80 81 8f b3 00 a9 40 61 40   .OT..........@a@
+0030   01 01 01 01 01 01 4e 0c 80 a0 20 e0 2d 10 08 60   ......N... .-..`
+0040   22 00 06 44 21 00 00 18 00 00 00 10 00 00 0a 20   "..D!.......... 
+0050   20 20 20 20 20 20 20 20 20 20 00 00 00 10 00 00             ......
+0060   0a 20 20 20 20 20 20 20 20 20 20 20 00 00 00 fc   .           ....
+0070   00 4c 43 44 20 4d 4f 4e 49 54 4f 52 20 20 01 21   .LCD MONITOR  .!
+0080   02 03 22 71 4f 90 01 02 03 04 05 06 07 11 12 13   .."qO...........
+0090   14 15 16 1f 23 09 7f 07 83 01 00 00 65 03 0c 00   ....#.......e...
+00a0   10 00 02 3a 80 18 71 38 2d 40 58 2c 45 00 d7 40   ...:..q8-@X,E..@
+00b0   32 00 00 1e 01 1d 00 72 51 d0 1e 20 6e 28 55 00   2......rQ.. n(U.
+00c0   d7 40 32 00 00 1e 01 1d 80 18 71 1c 16 20 58 2c   .@2.......q.. X,
+00d0   25 00 d7 40 32 00 00 9e 00 00 00 00 00 00 00 00   %..@2...........
+00e0   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   ................
+00f0   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 bb   ................
         No i2c-N subdirectory

   Connector: card0-Writeback-1
      /sys/class/drm/card0-Writeback-1/enabled                              =  disabled
      /sys/class/drm/card0-Writeback-1/status                               =  unknown
      /sys/class/drm/card0-Writeback-1/edid                                 :  0 length
         No i2c-N subdirectory

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
Query file system for i2c nodes under /sys/class/drm/card*/ddc/i2c-dev/...
   drwxr-xr-x 3 root root 0 Aug 26 11:40 /sys/class/drm/card0/card0-HDMI-A-1/ddc/i2c-dev/i2c-2

Device Identifier Cross Reference Report

Video related contents of /etc/modprobe.d
   /etc/modprobe.d/rpi.conf:#blacklist vc4

****** Dumping sysfs i2c entries ******

*** Character device major numbers of interest: ***
    89 i2c
   226 drm

*** Top Level I2C Related Nodes ***

   ls -l /sys/bus/pci/devices ...
      total 0

   ls -l /sys/bus/i2c/devices ...
      total 0
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 i2c-2 -> ../../../devices/platform/soc/3f805000.i2c/i2c-2

   ls -l /sys/bus/ddcci/devices ...
      ls: cannot access '/sys/bus/ddcci/devices': No such file or directory

   ls -l /sys/bus/platform/devices ...
      total 0
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f004000.txp -> ../../../devices/platform/soc/3f004000.txp
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f007000.dma-controller -> ../../../devices/platform/soc/3f007000.dma-controller
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f00b840.mailbox -> ../../../devices/platform/soc/3f00b840.mailbox
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f00b880.mailbox -> ../../../devices/platform/soc/3f00b880.mailbox
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f100000.watchdog -> ../../../devices/platform/soc/3f100000.watchdog
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f101000.cprman -> ../../../devices/platform/soc/3f101000.cprman
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f104000.rng -> ../../../devices/platform/soc/3f104000.rng
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f200000.gpio -> ../../../devices/platform/soc/3f200000.gpio
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f200000.gpiomem -> ../../../devices/platform/soc/3f200000.gpiomem
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f202000.mmc -> ../../../devices/platform/soc/3f202000.mmc
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f206000.pixelvalve -> ../../../devices/platform/soc/3f206000.pixelvalve
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f207000.pixelvalve -> ../../../devices/platform/soc/3f207000.pixelvalve
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f212000.thermal -> ../../../devices/platform/soc/3f212000.thermal
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f215000.aux -> ../../../devices/platform/soc/3f215000.aux
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f215040.serial -> ../../../devices/platform/soc/3f215040.serial
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f300000.mmcnr -> ../../../devices/platform/soc/3f300000.mmcnr
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f400000.hvs -> ../../../devices/platform/soc/3f400000.hvs
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f805000.i2c -> ../../../devices/platform/soc/3f805000.i2c
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f807000.pixelvalve -> ../../../devices/platform/soc/3f807000.pixelvalve
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f902000.hdmi -> ../../../devices/platform/soc/3f902000.hdmi
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3f980000.usb -> ../../../devices/platform/soc/3f980000.usb
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 3fc00000.v3d -> ../../../devices/platform/soc/3fc00000.v3d
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 arm-pmu -> ../../../devices/platform/arm-pmu
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 bcm2835-power -> ../../../devices/platform/soc/3f100000.watchdog/bcm2835-power
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 bcm2835-wdt -> ../../../devices/platform/soc/3f100000.watchdog/bcm2835-wdt
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 cam1_regulator -> ../../../devices/platform/cam1_regulator
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 cam_dummy_reg -> ../../../devices/platform/cam_dummy_reg
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 chosen -> ../../../devices/platform/chosen
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 clocks -> ../../../devices/platform/clocks
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 cpufreq-dt -> ../../../devices/platform/cpufreq-dt
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 fixedregulator_3v3 -> ../../../devices/platform/fixedregulator_3v3
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 fixedregulator_5v0 -> ../../../devices/platform/fixedregulator_5v0
      lrwxrwxrwx 1 root root 0 Aug 31 20:23 hdmi-audio-codec.0.auto -> ../../../devices/platform/soc/soc:gpu/hdmi-audio-codec.0.auto
      lrwxrwxrwx 1 root root 0 Aug 31 20:23 hdmi-audio-codec.1.auto -> ../../../devices/platform/soc/3f902000.hdmi/hdmi-audio-codec.1.auto
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 kgdboc -> ../../../devices/platform/kgdboc
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 leds -> ../../../devices/platform/leds
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 phy -> ../../../devices/platform/phy
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 raspberrypi-cpufreq -> ../../../devices/platform/soc/soc:firmware/soc:firmware:clocks/raspberrypi-cpufreq
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 raspberrypi-hwmon -> ../../../devices/platform/soc/soc:firmware/raspberrypi-hwmon
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 serial8250 -> ../../../devices/platform/serial8250
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc -> ../../../devices/platform/soc
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:firmware -> ../../../devices/platform/soc/soc:firmware
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:firmware:clocks -> ../../../devices/platform/soc/soc:firmware/soc:firmware:clocks
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:firmware:expgpio -> ../../../devices/platform/soc/soc:firmware/soc:firmware:expgpio
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:firmware:vcio -> ../../../devices/platform/soc/soc:firmware/soc:firmware:vcio
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:gpu -> ../../../devices/platform/soc/soc:gpu
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:nvmem -> ../../../devices/platform/soc/soc:nvmem
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:nvmem:nvmem_cust -> ../../../devices/platform/soc/soc:nvmem/soc:nvmem:nvmem_cust
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:nvmem:nvmem_otp -> ../../../devices/platform/soc/soc:nvmem/soc:nvmem:nvmem_otp
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 soc:power -> ../../../devices/platform/soc/soc:power
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 timer -> ../../../devices/platform/timer

   ls -l /sys/class/drm* ...
      total 0
      lrwxrwxrwx 1 root root    0 Aug 26 11:40 card0 -> ../../devices/platform/soc/soc:gpu/drm/card0
      lrwxrwxrwx 1 root root    0 Aug 26 11:40 card0-HDMI-A-1 -> ../../devices/platform/soc/soc:gpu/drm/card0/card0-HDMI-A-1
      lrwxrwxrwx 1 root root    0 Aug 26 11:40 card0-Writeback-1 -> ../../devices/platform/soc/soc:gpu/drm/card0/card0-Writeback-1
      lrwxrwxrwx 1 root root    0 Aug 26 11:40 renderD128 -> ../../devices/platform/soc/soc:gpu/drm/renderD128
      -r--r--r-- 1 root root 4096 Aug 31 20:23 version

   ls -l /sys/class/i2c* ...
      total 0
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 i2c-2 -> ../../devices/platform/soc/3f805000.i2c/i2c-2/i2c-dev/i2c-2

   ls -l /sys/class/backlight ...
      total 0

   ls -l /sys/class/vfio* ...
      ls: cannot access '/sys/class/vfio*': No such file or directory

   Char major: 89 i2c
      lrwxrwxrwx 1 root root 0 Aug 31 20:23 /sys/dev/char/89:2 -> ../../devices/platform/soc/3f805000.i2c/i2c-2/i2c-dev/i2c-2

   Char major: 226 drm
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 /sys/dev/char/226:0 -> ../../devices/platform/soc/soc:gpu/drm/card0
      lrwxrwxrwx 1 root root 0 Aug 26 11:40 /sys/dev/char/226:128 -> ../../devices/platform/soc/soc:gpu/drm/renderD128

*** Detailed /sys/bus/pci/devices scan ***

*** Scan /sys/bus/i2c ***

   Examining /sys/bus/i2c/devices:

   Examining /sys/bus/i2c/devices/i2c-2...
         /sys/bus/i2c/devices/i2c-2                                            -> /sys/devices/platform/soc/3f805000.i2c/i2c-2
         /sys/devices/platform/soc/3f805000.i2c/i2c-2/name                     =  bcm2835 (i2c@7e805000)
         /sys/devices/platform/soc/3f805000.i2c/i2c-2/i2c-dev/i2c-2/dev        =  89:2
         /sys/devices/platform/soc/3f805000.i2c/i2c-2/i2c-dev/i2c-2/name       =  bcm2835 (i2c@7e805000)
         /sys/devices/platform/soc/3f805000.i2c/i2c-2/..                       -> /sys/devices/platform/soc/3f805000.i2c
         /sys/devices/platform/soc/3f805000.i2c                                :  No drm_dp_aux subdirectory found
         /sys/devices/platform/soc/3f805000.i2c/class                          :  Not Found

*** Sys_Drm_Connector report: Detailed /sys/class/drm report: ***

   Display connectors reported by /sys:
   Connector:    card0-HDMI-A-1
      i2c_busno:    2
      connector_id: 35
      name:         (null)
      enabled:      enabled
      status:       connected
      edid:
        +0          +4          +8          +c            0   4   8   c   
+0000   00 ff ff ff ff ff ff 00 1d 85 01 24 01 00 00 00   ...........$....
+0010   20 12 01 03 80 2b 1b 6d ef c5 c6 a3 57 4a 9c 23    ....+.m....WJ.#
+0020   12 4f 54 af ef 80 81 80 81 8f b3 00 a9 40 61 40   .OT..........@a@
+0030   01 01 01 01 01 01 4e 0c 80 a0 20 e0 2d 10 08 60   ......N... .-..`
+0040   22 00 06 44 21 00 00 18 00 00 00 10 00 00 0a 20   "..D!.......... 
+0050   20 20 20 20 20 20 20 20 20 20 00 00 00 10 00 00             ......
+0060   0a 20 20 20 20 20 20 20 20 20 20 20 00 00 00 fc   .           ....
+0070   00 4c 43 44 20 4d 4f 4e 49 54 4f 52 20 20 01 21   .LCD MONITOR  .!
+0080   02 03 22 71 4f 90 01 02 03 04 05 06 07 11 12 13   .."qO...........
+0090   14 15 16 1f 23 09 7f 07 83 01 00 00 65 03 0c 00   ....#.......e...
+00a0   10 00 02 3a 80 18 71 38 2d 40 58 2c 45 00 d7 40   ...:..q8-@X,E..@
+00b0   32 00 00 1e 01 1d 00 72 51 d0 1e 20 6e 28 55 00   2......rQ.. n(U.
+00c0   d7 40 32 00 00 1e 01 1d 80 18 71 1c 16 20 58 2c   .@2.......q.. X,
+00d0   25 00 d7 40 32 00 00 9e 00 00 00 00 00 00 00 00   %..@2...........
+00e0   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   ................
+00f0   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 bb   ................

   Connector:    card0-Writeback-1
      i2c_busno:    -1
      connector_id: 56
      name:         (null)
      enabled:      disabled
      status:       unknown
      edid:         None


*** Sysfs_I2C_Info report ***
   All Sysfs_I2C_Info records
      Sysfs_I2C_Info at: 0x5584397530
         busno:                     2
         name:                      bcm2835 (i2c@7e805000)
         adapter_path:              /sys
         adapter_class:             
         driver:                    (null)
         driver_version:            (null)
         conflicting_driver_names:  
         adapter supports DRM:      false

*** Sysfs I2C devices possibly associated with displays ***
Nothing to read from /sys/class
Nothing to read from /sys/class
I2C buses to check: 

*** Sys_Conflicting_Driver report: Check for Conflicting Device Drivers ***
   No conflicting drivers found

*** Sysfs Reports Done ***


*** All sysfs class attributes ***

Drm_Connector_State at: 0x5584388e90
   cardno:              0
   connector_id:        35
   connector_type:      11 - DRM_MODE_CONNECTOR_HDMIA
   connector_type_id:   1
   connection:          1 - DRM_MODE_CONNECTED
   Properties:
      dpms:             3 - Off
      link_status:      0 - Good
      subconnector:     0 - UNK
      edid:             GLE, LCD MONITOR, 

*** Extended dump of sysfs video devices for ARM architecture ***

   No devices with class 0x03nnnn found.
*** Examining displaylink related attributes ***

   No displaylink devices found.

*** XDG Directory Settings ***
   XDG Base Directory Environment Variables:
      $XDG_DATA_HOME  : (null)
      $XDG_CONFIG_HOME: (null)
      $XDG_STATE_HOME : (null)
      $XDG_CACHE_HOME : (null)
      $XDG_DATA_DIRS  : (null)
      $XDG_CONFIG_DIRS: (null)

XDG Utility Functions:
      xdg_data_home_dir():      /root/.local/share/
      xdg_config_home_dir():    /root/.config/
      xdg_cache_home_dir():     /root/.cache/
      xdg_state_home_dir():     /root/.local/state/
      xdg_data_path():          /root/.local/share/:/usr/local/share/:/usr/share
      xdg_config_path():        /root/.config/:/etc/xdg

*** ddcutil Configuration, Cache, and Data files ***

   Configuration file ddcutilrc not found


Examining cache files...

Reading /root/.cache/ddcutil/capabilities:
   Error reading file /root/.cache/ddcutil/capabilities: No such file or directory

Reading /root/.cache/ddcutil/dsa:
   FORMAT 2
   * DEV  /dev/i2c device
   * EC   EDID check sum byte
   * C    current step
   * I    interval remaining
   * L    current lookback
   * DEV EC C I L Values
   * Values {tries required, step, epoch seconds}

   Files on data path:

*** environment command complete ***

EXECUTION STATISTICS

Maxtries Settings:
Operation Type                    Current  Default     Min     Max
Write only exchange tries:             15        4       4      15
Write read exchange tries:             15        4      10      15
Multi-part read exchange tries:        15        4       8      15
Multi-part_write exchange tries:       15        4       8      15


Retry statistics for write only
   No tries attempted

Retry statistics for write-read
   No tries attempted

Retry statistics for multi-part read
   No tries attempted

Retry statistics for multi-part write
   No tries attempted

DDC Related Errors:  None

Total errors: 0

Errors Wrapped in Retry:  None

Total errors: 0


IO and Sleep Events:
   Total IO events:          0
   IO error count:           0
   Total sleep events:       0

   Sleep Event type      Count
   SE_WRITE_TO_READ              0
   SE_POST_WRITE                 0
   SE_POST_READ                  0
   SE_POST_SAVE_SETTINGS         0
   SE_PRE_MULTI_PART_READ        0
   SE_POST_CAP_TABLE_SEGMENT     0
   SE_SPECIAL                    0

Call Stats:
   Type                                     Count    Millisec  (      Nanosec)
   Totals:                                      0           0  (            0)

Sleep Call Stats:
   Total sleep calls:                                       0
   Requested sleep time milliseconds :                      0
   Actual sleep milliseconds (nanosec):                     0  (            0)

Total elapsed milliseconds (nanoseconds):                1447  (   1447254460)

Total non sleep system call time:          0 milliseconds
Total sleep call time:                     0 milliseconds
Elapsed time:                           1447 milliseconds

[rockowitz]

Please submit the output of the following commands:

ls -ld /sys/devices/soc*
sudo ddcutil environment -verbose --trcfunc sysfs_is_ignorable_i2c_device

Please submit the output as an attachment rather than inline. Posting long output inline makes a thread difficult to follow.

[rockowitz]

The environment command reports ddcutil 2.2.6. The fix related to pull request #619 - do not ignore sysfs class being zero, may have already addressed your bug. Please retest with branch 2.2.8-dev.

[mikecflood]

I retested with 2.2.8.-dev and this does work now.

Note: when I ran "ddcuti enviroment --verbose", I got:

Unrecognized ddcutil command: environment

I understand this is the dev branch so might be intended.

[rockowitz]

I verified the version I'm running:

rock@banner:/shared/playproj/i2c$ ddcutil --version
ddcutil 2.2.8-DEV

Ran the command string you supplied:

rock@banner:/shared/playproj/i2c$ ddcuti enviroment --verbose
Command 'ddcuti' not found, did you mean:
  command 'ddcui' from deb ddcui (0.6.0-6)
  command 'ddcutil' from deb ddcutil (2.2.5-1)
Try: sudo apt install <deb name>

Fixed the spelling of "ddcutil":

rock@banner:/shared/playproj/i2c$ ddcutil enviroment --verbose
Applying ddcutil options from /home/rock/.config/ddcutil/ddcutilrc: --syslog debug --trace-to-syslog --trace conn --trace api --trace ddcio --trace ddc --i15 1 --bus-drm-connector "6 card1-DP-1" --f18
   Unrecognized ddcutil command: enviroment

Fixed the spelling of "environment:":

rock@banner:/shared/playproj/i2c$ ddcutil environment --verbose
Applying ddcutil options from /home/rock/.config/ddcutil/ddcutilrc: --syslog debug --trace-to-syslog --trace conn --trace api --trace ddcio --trace ddc --i15 1 --bus-drm-connector "6 card1-DP-1" --f18
(main                          ) Starting ddcutil execution, Wed Sep  2 05:02:58 2026
(submaster_initializer         ) Starting  parsed_cmd = 0x5a2ace0e38b0

Clearly not a bug. It's your typing.