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#1 2020-06-12 19:23:56

toru
Member
Registered: 2020-04-12
Posts: 26  

Backlight control problem

I've been looking into how to fix this problem of being unable to set the monitor backlight brightness on this Acer Aspire 3 (A315-21-95KF) laptop (Devuan Beowulf - first RC).  I tried quite a bit more to fix this on my own out of respect for your time, but so far it has persisted.  This is about the internal monitor.  If I'm not mistaken, the computer just boots with full brightness and stays that way, and I want to be able to change it, and to do that without rebooting.  Command line solutions are fine for me.  I think this issue might be because of the switch to Wayland, but I'm not sure.  (EDIT:  Come to think of it, I think I had the same problem on this laptop with Ascii)  The reason I need to fix this is because in my situation I need to conserve power when I can.

$ lspci
00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Stoney [Radeon R2/R3/R4/R5 Graphics] (rev da)

I quickly found or heard things suggesting me to set things like this in /etc/default/grub under GRUB_CMDLINE_LINUX_DEFAULT:
acpi_osi=Linux
acpi_osi=!Windows_2012
acpi_osi=!Windows2012
acpi_backlight=vendor
pci=noacpi

But none of those worked.  acpi_osi=Linux and acpi_osi=!Windows_2012 create a backlight slider in the MATE power settings, but when I slide it, it doesn't change anything.  Using acpi_backlight=vendor at the same time makes the slider disappear.  The last one actually makes the computer end up in a very limited busybox shell upon booting, with the internal keyboard not working, but for some reason lets me use a USB keyboard still, and booting in recovery mode seems to still work fine.  (So I've edited pci=noacpi out now and we're good except that the original backlight problem still remains)

Also there is this:

$ ls -a /sys/class/backlight/
.  ..

And with acpi_osi=Linux:

$ ls -a /sys/class/backlight/
.  ..  acpi_video0

For some reason root can't write to any of these files:
/sys/class/backlight/acpi_video0/brightness
/sys/class/backlight/acpi_video0/max_brightness
/sys/class/backlight/acpi_video0/actual_brightness

Then I read about /etc/X11/xorg.conf but I don't have one.  I tried installing libacpi0 but it didn't fix it.  I tried xbacklight but it said "No outputs have backlight property" even if I'm using acpi_osi=Linux.

Then I tried radeontool.  But it doesn't seem very useful to me with my limited understanding of it.

I tried making a /usr/share/X11/xorg.conf.d/10-backlight.conf with this:

Section "Device"
       Identifier "Radeon"
       Driver "radeon"
#       Option "AccelMethod" "uxa"
EndSection

But then when I rebooted, it never went to lightdm.

dmesg gave me this:

[    0.000000] BIOS-e820: [mem 0x00000000d93b6000-0x00000000d9db5fff] ACPI NVS
[    0.000000] BIOS-e820: [mem 0x00000000d9db6000-0x00000000defbefff] usable
[    0.000000] BIOS-e820: [mem 0x00000000defbf000-0x00000000df8befff] reserved
[    0.000000] BIOS-e820: [mem 0x00000000df8bf000-0x00000000dfbbefff] ACPI NVS
[    0.000000] BIOS-e820: [mem 0x00000000dfbbf000-0x00000000dfbfefff] ACPI data

[    0.022118] ACPI: Early table checksum verification disabled
[    0.022763] ACPI: RSDP 0x00000000000FE020 000024 (v02 ACRSYS)
[    0.022767] ACPI: XSDT 0x00000000DFBD6188 0000DC (v01 ACRSYS ACRPRDCT 00000001      01000013)
[    0.022772] ACPI: FACP 0x00000000DFBF9000 00010C (v05 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022778] ACPI: DSDT 0x00000000DFBE8000 00907C (v01 ACRSYS ACRPRDCT 00040000 1025 00040000)
[    0.022780] ACPI: FACS 0x00000000DFB86000 000040
[    0.022782] ACPI: MSDM 0x00000000DFBFC000 000055 (v03 INSYDE H2O BIOS 00000001 ACPI 00040000)
[    0.022785] ACPI: BOOT 0x00000000DFBFA000 000028 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022787] ACPI: HPET 0x00000000DFBF8000 000038 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022789] ACPI: MCFG 0x00000000DFBF6000 00003C (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022791] ACPI: WDAT 0x00000000DFBF3000 00017C (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022793] ACPI: UEFI 0x00000000DFBE7000 000042 (v01 ACRSYS ACRPRDCT 00000000 1025 00040000)
[    0.022795] ACPI: SSDT 0x00000000DFBF5000 0006B2 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022797] ACPI: IVRS 0x00000000DFBDB000 0000D0 (v02 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022799] ACPI: TPM2 0x00000000DFBD8000 000034 (v03 ACRSYS ACRPRDCT 00000002 1025 00040000)
[    0.022801] ACPI: SSDT 0x00000000DFBD4000 001616 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022803] ACPI: FPDT 0x00000000DFBD1000 000044 (v01 ACRSYS ACRPRDCT 00000002 1025 00040000)
[    0.022805] ACPI: UEFI 0x00000000DFBFD000 000236 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022807] ACPI: SPCR 0x00000000DFBF4000 000050 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022809] ACPI: SSDT 0x00000000DFBE1000 0056D2 (v01 ACRSYS ACRPRDCT 00001000 1025 00040000)
[    0.022811] ACPI: CRAT 0x00000000DFBDA000 0002E8 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022812] ACPI: SSDT 0x00000000DFBD7000 000174 (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022814] ACPI: APIC 0x00000000DFBF7000 000090 (v03 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022816] ACPI: SSDT 0x00000000DFBDC000 004B5B (v02 ACRSYS ACRPRDCT 00000002 1025 00040000)
[    0.022818] ACPI: SSDT 0x00000000DFBD2000 00165E (v01 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022820] ACPI: WDRT 0x00000000DFBF2000 000047 (v01 ACRSYS ACRPRDCT 00000000 1025 00040000)
[    0.022822] ACPI: ASF! 0x00000000DFBFB000 0000A5 (v32 ACRSYS ACRPRDCT 00000001 1025 00040000)
[    0.022824] ACPI: SSDT 0x00000000DFBD9000 000482 (v01 ACRSYS ACRPRDCT 00001000 1025 00040000)
[    0.022831] ACPI: Local APIC address 0xfee00000

[    0.052807] ACPI: PM-Timer IO Port: 0x408
[    0.052809] ACPI: Local APIC address 0xfee00000
[    0.052814] ACPI: LAPIC_NMI (acpi_id[0x00] high edge lint[0x1])
[    0.052815] ACPI: LAPIC_NMI (acpi_id[0x01] high edge lint[0x1])
[    0.052816] ACPI: LAPIC_NMI (acpi_id[0x02] high edge lint[0x1])
[    0.052816] ACPI: LAPIC_NMI (acpi_id[0x03] high edge lint[0x1])
[    0.052824] IOAPIC[0]: apic_id 4, version 33, address 0xfec00000, GSI 0-23
[    0.052827] IOAPIC[1]: apic_id 5, version 33, address 0xfec01000, GSI 24-55
[    0.052829] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
[    0.052830] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level)
[    0.052832] ACPI: IRQ0 used by override.
[    0.052832] ACPI: IRQ9 used by override.
[    0.052834] Using ACPI (MADT) for SMP configuration information
[    0.052835] ACPI: HPET id: 0x10228210 base: 0xfed00000
[    0.052838] ACPI: SPCR: SPCR table version 1
[    0.052840] ACPI: SPCR: console: uart,io,0x3f8,115200

[    0.222570] ACPI: Core revision 20180810

[    0.382865] PM: Registering ACPI NVS region [mem 0xd93b6000-0xd9db5fff] (10485760 bytes)
[    0.382996] PM: Registering ACPI NVS region [mem 0xdf8bf000-0xdfbbefff] (3145728 bytes)

[    0.384057] ACPI FADT declares the system doesn't support PCIe ASPM, so disable it
[    0.384057] ACPI: bus type PCI registered
[    0.384057] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5

[    0.384057] ACPI FADT declares the system doesn't support PCIe ASPM, so disable it
[    0.384057] ACPI: bus type PCI registered
[    0.384057] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
[    0.384057] PCI: MMCONFIG for domain 0000 [bus 00-3f] at [mem 0xf8000000-0xfbffffff] (base 0xf8000000)
[    0.384057] PCI: MMCONFIG at [mem 0xf8000000-0xfbffffff] reserved in E820
[    0.384057] PCI: Using configuration type 1 for base access
[    0.384057] HugeTLB registered 1.00 GiB page size, pre-allocated 0 pages
[    0.384057] HugeTLB registered 2.00 MiB page size, pre-allocated 0 pages
[    0.384057] ACPI: Added _OSI(Module Device)
[    0.384057] ACPI: Added _OSI(Processor Device)
[    0.384057] ACPI: Added _OSI(3.0 _SCP Extensions)
[    0.384057] ACPI: Added _OSI(Processor Aggregator Device)
[    0.384057] ACPI: Added _OSI(Linux-Dell-Video)
[    0.384057] ACPI: Added _OSI(Linux-Lenovo-NV-HDMI-Audio)
[    0.384057] ACPI: Added _OSI(Linux)
[    0.392347] ACPI: 8 ACPI AML tables successfully acquired and loaded
[    0.394245] ACPI: [Firmware Bug]: BIOS _OSI(Linux) query honored via cmdline
[    0.395508] ACPI: EC: EC started
[    0.395508] ACPI: EC: interrupt blocked
[    0.395721] ACPI: \_SB_.PCI0.LPC0.EC0_: Used as first EC
[    0.395722] ACPI: \_SB_.PCI0.LPC0.EC0_: GPE=0x3, EC_CMD/EC_SC=0x66, EC_DATA=0x62
[    0.395724] ACPI: \_SB_.PCI0.LPC0.EC0_: Used as boot DSDT EC to handle transactions
[    0.395725] ACPI: Interpreter enabled
[    0.395741] ACPI: (supports S0 S3 S4 S5)
[    0.395743] ACPI: Using IOAPIC for interrupt routing
[    0.395849] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug
[    0.396070] ACPI: Enabled 3 GPEs in block 00 to 1F
[    0.396724] ACPI: Power Resource [WRST] (on)
[    0.397252] ACPI: Power Resource [P0U2] (off)
[    0.397278] ACPI: Power Resource [P3U2] (off)
[    0.397482] ACPI: Power Resource [P0U3] (off)
[    0.397507] ACPI: Power Resource [P3U3] (off)
[    0.398273] ACPI: Power Resource [P0ST] (on)
[    0.398300] ACPI: Power Resource [P3ST] (on)
[    0.398661] ACPI: Power Resource [P0SD] (off)
[    0.398685] ACPI: Power Resource [P3SD] (off)
[    0.400678] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])
[    0.400683] acpi PNP0A08:00: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI]
[    0.400777] acpi PNP0A08:00: _OSC: platform does not support [SHPCHotplug LTR]
[    0.400863] acpi PNP0A08:00: _OSC: OS now controls [PCIeHotplug PME AER PCIeCapability]
[    0.400864] acpi PNP0A08:00: FADT indicates ASPM is unsupported, using BIOS configuration
[    0.400876] acpi PNP0A08:00: [Firmware Info]: MMCONFIG for domain 0000 [bus 00-3f] only partially covers this bridge
[    0.400946] acpi PNP0A08:00: ignoring host bridge window [mem 0x000cc000-0x000cffff window] (conflicts with Video ROM [mem 0x000c0000-0x000cfdff])

[    0.409443] ACPI: PCI Interrupt Link [LNKA] (IRQs 3 5 6 10 11) *0, disabled.
[    0.409492] ACPI: PCI Interrupt Link [LNKB] (IRQs 3 5 6 10 11) *0, disabled.
[    0.409531] ACPI: PCI Interrupt Link [LNKC] (IRQs 3 5 6 10 11) *0, disabled.
[    0.409580] ACPI: PCI Interrupt Link [LNKD] (IRQs 3 5 6 10 11) *0, disabled.
[    0.409626] ACPI: PCI Interrupt Link [LNKE] (IRQs 3 5 6 10 11) *0, disabled.
[    0.409661] ACPI: PCI Interrupt Link [LNKF] (IRQs 3 5 6 10 11) *0, disabled.
[    0.409697] ACPI: PCI Interrupt Link [LNKG] (IRQs 3 5 6 10 11) *0, disabled.
[    0.409732] ACPI: PCI Interrupt Link [LNKH] (IRQs 3 5 6 10 11) *0, disabled.
[    0.410361] ACPI: EC: interrupt unblocked
[    0.410370] ACPI: EC: event unblocked
[    0.410376] ACPI: \_SB_.PCI0.LPC0.EC0_: GPE=0x3, EC_CMD/EC_SC=0x66, EC_DATA=0x62
[    0.410377] ACPI: \_SB_.PCI0.LPC0.EC0_: Used as boot DSDT EC to handle transactions and events

[    0.410447] PCI: Using ACPI for IRQ routing

[    0.421599] pnp: PnP ACPI init
[    0.421801] system 00:00: [mem 0xfec00000-0xfec01fff] could not be reserved
[    0.421809] system 00:00: [mem 0xfee00000-0xfee00fff] has been reserved
[    0.421811] system 00:00: [mem 0xf0a00000-0xf0afffff] has been reserved
[    0.421816] system 00:00: Plug and Play ACPI device, IDs PNP0c02 (active)
[    0.421919] pnp 00:01: Plug and Play ACPI device, IDs PNP0b00 (active)
[    0.421944] pnp 00:02: Plug and Play ACPI device, IDs PNP0303 (active)

[    0.422016] system 00:03: Plug and Play ACPI device, IDs PNP0c02 (active)
[    0.422068] system 00:04: [mem 0x000e0000-0x000fffff] could not be reserved
[    0.422070] system 00:04: [mem 0xff800000-0xffffffff] has been reserved
[    0.422072] system 00:04: Plug and Play ACPI device, IDs PNP0c01 (active)
[    0.422507] pnp: PnP ACPI: found 5 devices
[    0.428303] clocksource: acpi_pm: mask: 0xffffff max_cycles: 0xffffff, max_idle_ns: 2085701024 ns

[    1.359303] ACPI: Thermal Zone [THRM] (90 C)

[    1.407544] ACPI: bus type USB registered

[    4.744891] acpi_cpufreq: overriding BIOS provided _PSD data
[    4.827544] ACPI: AC Adapter [ACAD] (on-line)
[    4.829502] input: Power Button as /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0C:00/input/input4
[    4.829511] ACPI: Power Button [PWRB]
[    4.829573] input: Sleep Button as /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0E:00/input/input5
[    4.829578] ACPI: Sleep Button [SLPB]
[    4.829612] input: Lid Switch as /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0D:00/input/input6
[    4.829617] ACPI: Lid Switch [LID]
[    4.829652] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input7
[    4.830346] battery: ACPI: Battery Slot [BAT1] (battery present)
[    4.831018] ACPI: Power Button [PWRF]
[    4.854312] ACPI: Video Device [VGA] (multi-head: yes  rom: no  post: no)
[    4.854616] acpi device:00: registered as cooling_device2
[    4.854661] input: Video Bus as /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/LNXVIDEO:00/input/input8
[    4.909094] tpm_crb MSFT0101:00: can't request region for resource [mem 0xdfbba000-0xdfbbdfff]
[    4.909158] tpm_crb: probe of MSFT0101:00 failed with error -16
[    5.007936] acpi PNP0C14:01: duplicate WMI GUID 05901221-D566-11D1-B2F0-00A0C9062910 (first instance was on PNP0C14:00)

[    6.299461] acer_wmi: Acer Laptop ACPI-WMI Extras

Last edited by toru (2020-06-12 22:10:15)

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#2 2020-06-12 20:07:31

Micronaut
Member
Registered: 2019-07-04
Posts: 201  

Re: Backlight control problem

I just recently had this same struggle on a couple of older laptops. They use the Intel CPU video driver, not a third-party GPU, so this may not apply to your system. But here's the thread that I started:

https://dev1galaxy.org/viewtopic.php?id=3480

Offline

#3 2020-06-12 22:15:24

Head_on_a_Stick
Member
From: London
Registered: 2019-03-24
Posts: 3,125  
Website

Re: Backlight control problem

toru wrote:

For some reason root can't write to any of these files:
/sys/class/backlight/acpi_video0/brightness
/sys/class/backlight/acpi_video0/max_brightness
/sys/class/backlight/acpi_video0/actual_brightness

You should show us the exact command(s) that you used to try to write to the file.

I'm guessing that you tried something like

sudo echo $value > /sys/class/backlight/acpi_video0/brightness

^ That won't work because the elevated privileges conferred by the sudo command are lost in the redirection operation (>).

Use this instead:

sudo tee /sys/class/backlight/acpi_video0/brightness <<<'$value'

Or

sudo sh -c 'echo $value > /sys/class/backlight/acpi_video0/brightness'

In both cases replace $value with the actual numerical value (with the maximum determined by the content of /sys/class/backlight/acpi_video0/max_brightness).

toru wrote:

I tried making a /usr/share/X11/xorg.conf.d/10-backlight.conf with this:

Section "Device"
       Identifier "Radeon"
       Driver "radeon"
#       Option "AccelMethod" "uxa"
EndSection

But then when I rebooted, it never went to lightdm.

Perhaps your card needs the amdgpu driver, check the LightDM & X.Org logs and also the output of

lspci -k | grep -A3 VGA

Last edited by Head_on_a_Stick (2020-06-12 22:16:27)


Brianna Ghey — Rest In Power

Offline

#4 2020-06-13 01:10:31

toru
Member
Registered: 2020-04-12
Posts: 26  

Re: Backlight control problem

@Micronaut:  If you look in my above post (topic starter post), I tried making a file like that (10-backlight.conf), and then lightdm wouldn't start for some reason when I rebooted.  I believe I had already seen your thread and tried to make use of the 10-backlight.conf thing.  Not to say that there isn't any useful information in the thread otherwise.  Thank you for helping!

You should show us the exact command(s) that you used to try to write to the file.

sudo nano /sys/class/backlight/acpi_video0/brightness 
sudo nano /sys/class/backlight/acpi_video0/max_brightness 
sudo nano /sys/class/backlight/acpi_video0/actual_brightness

Is there a reason for why the commands you gave are more likely to receive permissions than this?  I have used sudo nano before on root-owned files without problems.  For example, I have used "sudo nano /etc/default/grub" lately.

Let's see, I found the xorg log in /var/log/Xorg.0.log.
And the lightdm log I found in /var/log/lightdm/lightdm.log

Alright I'm gonna retry that 10-backlight.conf thing again and look at those logs then, and...  Here's the output of that other command:

$ lspci -k | grep -A3 VGA
00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Stoney [Radeon R2/R3/R4/R5 Graphics] (rev da)
	Subsystem: Acer Incorporated [ALI] Stoney [Radeon R2/R3/R4/R5 Graphics]
	Kernel modules: amdgpu
00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Device 15b3

Thanks for helping by the way!  I appreciate it.

Last edited by toru (2020-06-13 01:12:50)

Offline

#5 2020-06-13 05:22:24

toru
Member
Registered: 2020-04-12
Posts: 26  

Re: Backlight control problem

lightdm.log:

[+0.04s] DEBUG: Logging to /var/log/lightdm/lightdm.log
[+0.04s] DEBUG: Starting Light Display Manager 1.26.0, UID=0 PID=1692
[+0.04s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d
[+0.04s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/01_debian.conf
[+0.04s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/40-kde-plasma-kf5.conf
[+0.04s] DEBUG:   [SeatDefaults] is now called [Seat:*], please update this configuration
[+0.04s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d
[+0.04s] DEBUG: Loading configuration dirs from /etc/xdg/lightdm/lightdm.conf.d
[+0.04s] DEBUG: Loading configuration from /etc/lightdm/lightdm.conf
[+0.04s] DEBUG: Registered seat module local
[+0.04s] DEBUG: Registered seat module xremote
[+0.04s] DEBUG: Registered seat module unity
[+0.04s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager
[+0.28s] DEBUG: Monitoring logind for seats
[+0.28s] DEBUG: New seat added from logind: seat0
[+0.28s] DEBUG: Seat seat0: Loading properties from config section Seat:*
[+0.28s] DEBUG: Seat seat0: Starting
[+0.28s] DEBUG: Seat seat0: Creating greeter session
[+0.37s] DEBUG: Seat seat0: Creating display server of type x
[+0.37s] DEBUG: posix_spawn avoided (fd close requested) 
[+0.37s] DEBUG: Could not run plymouth --ping: Failed to execute child process “plymouth” (No such file or directory)
[+0.37s] DEBUG: Using VT 7
[+0.37s] DEBUG: Seat seat0: Starting local X display on VT 7
[+0.37s] DEBUG: XServer 0: Logging to /var/log/lightdm/x-0.log
[+0.37s] DEBUG: XServer 0: Writing X server authority to /var/run/lightdm/root/:0
[+0.37s] DEBUG: XServer 0: Launching X Server
[+0.37s] DEBUG: Launching process 1800: /usr/bin/X :0 -seat seat0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
[+0.37s] DEBUG: XServer 0: Waiting for ready signal from X server :0
[+0.37s] DEBUG: Acquired bus name org.freedesktop.DisplayManager
[+0.37s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat0
[+1.99s] DEBUG: Loading users from org.freedesktop.Accounts
[+1.99s] DEBUG: User /org/freedesktop/Accounts/User1000 added
[+3.50s] DEBUG: posix_spawn avoided (automatic reaping requested) (fd close requested) 
[+3.51s] DEBUG: Process 1800 exited with return value 1
[+3.51s] DEBUG: XServer 0: X server stopped
[+3.51s] DEBUG: Releasing VT 7
[+3.51s] DEBUG: XServer 0: Removing X server authority /var/run/lightdm/root/:0
[+3.51s] DEBUG: Seat seat0: Display server stopped
[+3.51s] DEBUG: Seat seat0: Stopping session
[+3.51s] DEBUG: Seat seat0: Session stopped
[+3.51s] DEBUG: Seat seat0: Stopping display server, no sessions require it
[+3.51s] DEBUG: Seat seat0: Stopping; greeter display server failed to start
[+3.51s] DEBUG: Seat seat0: Stopping
[+3.51s] DEBUG: Seat seat0: Stopped
[+3.51s] DEBUG: Required seat has stopped
[+3.51s] DEBUG: Stopping display manager
[+3.51s] DEBUG: Display manager stopped
[+3.51s] DEBUG: Stopping daemon
[+3.51s] DEBUG: Exiting with return value 1

Xorg.0.log:  (I only removed the first 6 lines of it)

[    15.959] Build Date: 05 March 2019  08:11:12PM
[    15.959] xorg-server 2:1.20.4-1 (https://www.debian.org/support) 
[    15.959] Current version of pixman: 0.36.0
[    15.959] 	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
[    15.959] Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[    15.959] (==) Log file: "/var/log/Xorg.0.log", Time: Sat Jun 13 00:21:40 2020
[    16.054] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[    16.091] (==) No Layout section.  Using the first Screen section.
[    16.091] (==) No screen section available. Using defaults.
[    16.091] (**) |-->Screen "Default Screen Section" (0)
[    16.091] (**) |   |-->Monitor "<default monitor>"
[    16.093] (==) No device specified for screen "Default Screen Section".
	Using the first device section listed.
[    16.093] (**) |   |-->Device "Radeon"
[    16.093] (==) No monitor specified for screen "Default Screen Section".
	Using a default monitor configuration.
[    16.093] (==) Automatically adding devices
[    16.093] (==) Automatically enabling devices
[    16.093] (==) Automatically adding GPU devices
[    16.093] (==) Max clients allowed: 256, resource mask: 0x1fffff
[    16.261] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist.
[    16.261] 	Entry deleted from font path.
[    16.263] (==) FontPath set to:
	/usr/share/fonts/X11/misc,
	/usr/share/fonts/X11/100dpi/:unscaled,
	/usr/share/fonts/X11/75dpi/:unscaled,
	/usr/share/fonts/X11/Type1,
	/usr/share/fonts/X11/100dpi,
	/usr/share/fonts/X11/75dpi,
	built-ins
[    16.264] (==) ModulePath set to "/usr/lib/xorg/modules"
[    16.264] (II) The server relies on udev to provide the list of input devices.
	If no devices become available, reconfigure udev or disable AutoAddDevices.
[    16.264] (II) Loader magic: 0x55f3d4af3e20
[    16.264] (II) Module ABI versions:
[    16.264] 	X.Org ANSI C Emulation: 0.4
[    16.264] 	X.Org Video Driver: 24.0
[    16.264] 	X.Org XInput driver : 24.1
[    16.264] 	X.Org Server Extension : 10.0
[    16.265] (++) using VT number 7

[    16.266] (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
[    16.270] (--) PCI:*(0@0:1:0) 1002:98e4:1025:1192 rev 218, Mem @ 0xe0000000/268435456, 0xf0000000/8388608, 0xf0d00000/262144, I/O @ 0x00003000/256, BIOS @ 0x????????/131072
[    16.270] (II) LoadModule: "glx"
[    16.457] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[    16.665] (II) Module glx: vendor="X.Org Foundation"
[    16.665] 	compiled for 1.20.4, module version = 1.0.0
[    16.665] 	ABI class: X.Org Server Extension, version 10.0
[    16.665] (II) LoadModule: "radeon"
[    16.835] (II) Loading /usr/lib/xorg/modules/drivers/radeon_drv.so
[    16.985] (II) Module radeon: vendor="X.Org Foundation"
[    16.985] 	compiled for 1.20.4, module version = 19.0.1
[    16.985] 	Module class: X.Org Video Driver
[    16.985] 	ABI class: X.Org Video Driver, version 24.0
[    16.985] (II) RADEON: Driver for ATI/AMD Radeon chipsets:
	ATI Radeon Mobility X600 (M24), ATI FireMV 2400,
	ATI Radeon Mobility X300 (M24), ATI FireGL M24 GL,
	ATI Radeon X600 (RV380), ATI FireGL V3200 (RV380),
	ATI Radeon IGP320 (A3), ATI Radeon IGP330/340/350 (A4),
	ATI Radeon 9500, ATI Radeon 9600TX, ATI FireGL Z1, ATI Radeon 9800SE,
	ATI Radeon 9800, ATI FireGL X2, ATI Radeon 9600, ATI Radeon 9600SE,
	ATI Radeon 9600XT, ATI FireGL T2, ATI Radeon 9650, ATI FireGL RV360,
	ATI Radeon 7000 IGP (A4+), ATI Radeon 8500 AIW,
	ATI Radeon IGP320M (U1), ATI Radeon IGP330M/340M/350M (U2),
	ATI Radeon Mobility 7000 IGP, ATI Radeon 9000/PRO, ATI Radeon 9000,
	ATI Radeon X800 (R420), ATI Radeon X800PRO (R420),
	ATI Radeon X800SE (R420), ATI FireGL X3 (R420),
	ATI Radeon Mobility 9800 (M18), ATI Radeon X800 SE (R420),
	ATI Radeon X800XT (R420), ATI Radeon X800 VE (R420),
	ATI Radeon X850 (R480), ATI Radeon X850 XT (R480),
	ATI Radeon X850 SE (R480), ATI Radeon X850 PRO (R480),
	ATI Radeon X850 XT PE (R480), ATI Radeon Mobility M7,
	ATI Mobility FireGL 7800 M7, ATI Radeon Mobility M6,
	ATI FireGL Mobility 9000 (M9), ATI Radeon Mobility 9000 (M9),
	ATI Radeon 9700 Pro, ATI Radeon 9700/9500Pro, ATI FireGL X1,
	ATI Radeon 9800PRO, ATI Radeon 9800XT,
	ATI Radeon Mobility 9600/9700 (M10/M11),
	ATI Radeon Mobility 9600 (M10), ATI Radeon Mobility 9600 (M11),
	ATI FireGL Mobility T2 (M10), ATI FireGL Mobility T2e (M11),
	ATI Radeon, ATI FireGL 8700/8800, ATI Radeon 8500, ATI Radeon 9100,
	ATI Radeon 7500, ATI Radeon VE/7000, ATI ES1000,
	ATI Radeon Mobility X300 (M22), ATI Radeon Mobility X600 SE (M24C),
	ATI FireGL M22 GL, ATI Radeon X800 (R423), ATI Radeon X800PRO (R423),
	ATI Radeon X800LE (R423), ATI Radeon X800SE (R423),
	ATI Radeon X800 XTP (R430), ATI Radeon X800 XL (R430),
	ATI Radeon X800 SE (R430), ATI Radeon X800 (R430),
	ATI FireGL V7100 (R423), ATI FireGL V5100 (R423),
	ATI FireGL unknown (R423), ATI Mobility FireGL V5000 (M26),
	ATI Mobility Radeon X700 XL (M26), ATI Mobility Radeon X700 (M26),
	ATI Radeon X550XTX, ATI Radeon 9100 IGP (A5),
	ATI Radeon Mobility 9100 IGP (U3), ATI Radeon XPRESS 200,
	ATI Radeon XPRESS 200M, ATI Radeon 9250, ATI Radeon 9200,
	ATI Radeon 9200SE, ATI FireMV 2200, ATI Radeon X300 (RV370),
	ATI Radeon X600 (RV370), ATI Radeon X550 (RV370),
	ATI FireGL V3100 (RV370), ATI FireMV 2200 PCIE (RV370),
	ATI Radeon Mobility 9200 (M9+), ATI Mobility Radeon X800 XT (M28),
	ATI Mobility FireGL V5100 (M28), ATI Mobility Radeon X800 (M28),
	ATI Radeon X850, ATI unknown Radeon / FireGL (R480),
	ATI Radeon X800XT (R423), ATI FireGL V5000 (RV410),
	ATI Radeon X700 XT (RV410), ATI Radeon X700 PRO (RV410),
	ATI Radeon X700 SE (RV410), ATI Radeon X700 (RV410),
	ATI Radeon X1800, ATI Mobility Radeon X1800 XT,
	ATI Mobility Radeon X1800, ATI Mobility FireGL V7200,
	ATI FireGL V7200, ATI FireGL V5300, ATI Mobility FireGL V7100,
	ATI FireGL V7300, ATI FireGL V7350, ATI Radeon X1600, ATI RV505,
	ATI Radeon X1300/X1550, ATI Radeon X1550, ATI M54-GL,
	ATI Mobility Radeon X1400, ATI Radeon X1550 64-bit,
	ATI Mobility Radeon X1300, ATI Radeon X1300, ATI FireGL V3300,
	ATI FireGL V3350, ATI Mobility Radeon X1450,
	ATI Mobility Radeon X2300, ATI Mobility Radeon X1350,
	ATI FireMV 2250, ATI Radeon X1650, ATI Mobility FireGL V5200,
	ATI Mobility Radeon X1600, ATI Radeon X1300 XT/X1600 Pro,
	ATI FireGL V3400, ATI Mobility FireGL V5250,
	ATI Mobility Radeon X1700, ATI Mobility Radeon X1700 XT,
	ATI FireGL V5200, ATI Radeon X2300HD, ATI Mobility Radeon HD 2300,
	ATI Radeon X1950, ATI Radeon X1900, ATI AMD Stream Processor,
	ATI RV560, ATI Mobility Radeon X1900, ATI Radeon X1950 GT, ATI RV570,
	ATI FireGL V7400, ATI Radeon 9100 PRO IGP,
	ATI Radeon Mobility 9200 IGP, ATI Radeon X1200, ATI RS740,
	ATI RS740M, ATI Radeon HD 2900 XT, ATI Radeon HD 2900 Pro,
	ATI Radeon HD 2900 GT, ATI FireGL V8650, ATI FireGL V8600,
	ATI FireGL V7600, ATI Radeon 4800 Series, ATI Radeon HD 4870 x2,
	ATI Radeon HD 4850 x2, ATI FirePro V8750 (FireGL),
	ATI FirePro V7760 (FireGL), ATI Mobility RADEON HD 4850,
	ATI Mobility RADEON HD 4850 X2, ATI FirePro RV770,
	AMD FireStream 9270, AMD FireStream 9250, ATI FirePro V8700 (FireGL),
	ATI Mobility RADEON HD 4870, ATI Mobility RADEON M98,
	ATI FirePro M7750, ATI M98, ATI Mobility Radeon HD 4650,
	ATI Radeon RV730 (AGP), ATI Mobility Radeon HD 4670,
	ATI FirePro M5750, ATI RV730XT [Radeon HD 4670], ATI RADEON E4600,
	ATI Radeon HD 4600 Series, ATI RV730 PRO [Radeon HD 4650],
	ATI FirePro V7750 (FireGL), ATI FirePro V5700 (FireGL),
	ATI FirePro V3750 (FireGL), ATI Mobility Radeon HD 4830,
	ATI Mobility Radeon HD 4850, ATI FirePro M7740, ATI RV740,
	ATI Radeon HD 4770, ATI Radeon HD 4700 Series, ATI RV610,
	ATI Radeon HD 2400 XT, ATI Radeon HD 2400 Pro,
	ATI Radeon HD 2400 PRO AGP, ATI FireGL V4000, ATI Radeon HD 2350,
	ATI Mobility Radeon HD 2400 XT, ATI Mobility Radeon HD 2400,
	ATI RADEON E2400, ATI FireMV 2260, ATI RV670, ATI Radeon HD3870,
	ATI Mobility Radeon HD 3850, ATI Radeon HD3850,
	ATI Mobility Radeon HD 3850 X2, ATI Mobility Radeon HD 3870,
	ATI Mobility Radeon HD 3870 X2, ATI Radeon HD3870 X2,
	ATI FireGL V7700, ATI Radeon HD3690, AMD Firestream 9170,
	ATI Radeon HD 4550, ATI Radeon RV710, ATI Radeon HD 4350,
	ATI Mobility Radeon 4300 Series, ATI Mobility Radeon 4500 Series,
	ATI FirePro RG220, ATI Mobility Radeon 4330, ATI RV630,
	ATI Mobility Radeon HD 2600, ATI Mobility Radeon HD 2600 XT,
	ATI Radeon HD 2600 XT AGP, ATI Radeon HD 2600 Pro AGP,
	ATI Radeon HD 2600 XT, ATI Radeon HD 2600 Pro, ATI Gemini RV630,
	ATI Gemini Mobility Radeon HD 2600 XT, ATI FireGL V5600,
	ATI FireGL V3600, ATI Radeon HD 2600 LE,
	ATI Mobility FireGL Graphics Processor, ATI Radeon HD 3470,
	ATI Mobility Radeon HD 3430, ATI Mobility Radeon HD 3400 Series,
	ATI Radeon HD 3450, ATI Radeon HD 3430, ATI FirePro V3700,
	ATI FireMV 2450, ATI Radeon HD 3600 Series, ATI Radeon HD 3650 AGP,
	ATI Radeon HD 3600 PRO, ATI Radeon HD 3600 XT,
	ATI Mobility Radeon HD 3650, ATI Mobility Radeon HD 3670,
	ATI Mobility FireGL V5700, ATI Mobility FireGL V5725,
	ATI Radeon HD 3200 Graphics, ATI Radeon 3100 Graphics,
	ATI Radeon HD 3300 Graphics, ATI Radeon 3000 Graphics, SUMO, SUMO2,
	ATI Radeon HD 4200, ATI Radeon 4100, ATI Mobility Radeon HD 4200,
	ATI Mobility Radeon 4100, ATI Radeon HD 4290, ATI Radeon HD 4250,
	AMD Radeon HD 6310 Graphics, AMD Radeon HD 6250 Graphics,
	AMD Radeon HD 6300 Series Graphics,
	AMD Radeon HD 6200 Series Graphics, PALM, CYPRESS,
	ATI FirePro (FireGL) Graphics Adapter, AMD Firestream 9370,
	AMD Firestream 9350, ATI Radeon HD 5800 Series,
	ATI Radeon HD 5900 Series, ATI Mobility Radeon HD 5800 Series,
	ATI Radeon HD 5700 Series, ATI Radeon HD 6700 Series,
	ATI Mobility Radeon HD 5000 Series, ATI Mobility Radeon HD 5570,
	ATI Radeon HD 5670, ATI Radeon HD 5570, ATI Radeon HD 5500 Series,
	REDWOOD, ATI Mobility Radeon Graphics, CEDAR, ATI FirePro 2270,
	ATI Radeon HD 5450, CAYMAN, AMD Radeon HD 6900 Series,
	AMD Radeon HD 6900M Series, Mobility Radeon HD 6000 Series, BARTS,
	AMD Radeon HD 6800 Series, AMD Radeon HD 6700 Series, TURKS, CAICOS,
	ARUBA, TAHITI, PITCAIRN, VERDE, OLAND, HAINAN, BONAIRE, KABINI,
	MULLINS, KAVERI, HAWAII
[    16.992] (EE) No devices detected.
[    16.992] (EE) 
Fatal server error:
[    16.992] (EE) no screens found(EE) 
[    16.992] (EE) 
Please consult the The X.Org Foundation support 
	 at http://wiki.x.org
 for help. 
[    16.992] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[    16.992] (EE) 
[    16.992] (EE) Server terminated with error (1). Closing log file.

Offline

#6 2020-06-13 11:22:49

Head_on_a_Stick
Member
From: London
Registered: 2019-03-24
Posts: 3,125  
Website

Re: Backlight control problem

toru wrote:
sudo nano /sys/class/backlight/acpi_video0/brightness

That's an unusual way to modify the file but it should work (it did when I tried it in my Alpine Linux box). What actually happened when you tried? Did you see any error messages?

Do my suggested echo commands work?

toru wrote:
$ lspci -k | grep -A3 VGA
00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Stoney [Radeon R2/R3/R4/R5 Graphics] (rev da)
	Subsystem: Acer Incorporated [ALI] Stoney [Radeon R2/R3/R4/R5 Graphics]
	Kernel modules: amdgpu
00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Device 15b3

Looks like the amdgpu module is available but not loaded. Without a loaded kernel module your system will fall back to the VESA driver, which will offer poor performance and may be the reason why you're having trouble with the backlight.

Try adding radeon.cik_support=0 amdgpu.cik_support=1 as a kernel command line parameter to force the amdgpu module for your card.

Also check that you have installed the firmware-amd-graphics package, that will be needed for full performance.

toru wrote:

Xorg.0.log:

[    16.992] (EE) no screens found(EE)

Your configuration file is forcing the wrong driver for your card, it needs amdgpu(4) rather than radeon(4).


Brianna Ghey — Rest In Power

Offline

#7 2020-06-13 20:17:01

toru
Member
Registered: 2020-04-12
Posts: 26  

Re: Backlight control problem

First, thank you for sticking with me!

No, using your commands doesn't work either.  I didn't try them until now, though.

What happened with nano:
brightness:  [ Error writing lock file /sys/class/backlight/acpi_video0/.brightness.swp: Permission denied ]
max_brightness:  [ File '/sys/class/backlight/acpi_video0/max_brightness' is unwritable ]
actual_brightness:  [ File '/sys/class/backlight/acpi_video0/actual_brightness' is unwritable ]

What happened with your commands:
$ sudo sh -c 'echo 100 > /sys/class/backlight/acpi_video0/brightness'
sh: 1: echo: echo: I/O error
$ sudo sh -c 'echo 100 > /sys/class/backlight/acpi_video0/max_brightness'
sh: 1: cannot create /sys/class/backlight/acpi_video0/max_brightness: Permission denied
$ sudo sh -c 'echo 100 > /sys/class/backlight/acpi_video0/actual_brightness'
sh: 1: cannot create /sys/class/backlight/acpi_video0/actual_brightness: Permission denied
$ sudo tee /sys/class/backlight/acpi_video0/brightness <<<'100'
100
tee: /sys/class/backlight/acpi_video0/brightness: Invalid argument
$ sudo tee /sys/class/backlight/acpi_video0/max_brightness <<<'100'
tee: /sys/class/backlight/acpi_video0/max_brightness: Permission denied
100
$ sudo tee /sys/class/backlight/acpi_video0/actual_brightness <<<'100'
tee: /sys/class/backlight/acpi_video0/actual_brightness: Permission denied
100

Alright, going to try those kernel command line parameters.  And if I must, I will try firmware-amd-graphics.  I wish to avoid proprietary software if possible, but if there's no other way.

Also, I found this.  Do you think this could solve my problem?  https://cannibalcandy.wordpress.com/201 … acpi-woes/

Oh, also it looks like the same thing happened again with the amdgpu modification to 10-backlight.conf:

[    15.419] (II) LoadModule: "amdgpu"
[    15.420] (II) Loading /usr/lib/xorg/modules/drivers/amdgpu_drv.so
[    15.546] (II) Module amdgpu: vendor="X.Org Foundation"
[    15.546] 	compiled for 1.20.3, module version = 18.1.99
[    15.546] 	Module class: X.Org Video Driver
[    15.546] 	ABI class: X.Org Video Driver, version 24.0
[    15.546] (II) AMDGPU: Driver for AMD Radeon:
	All GPUs supported by the amdgpu kernel driver
[    15.550] (II) AMDGPU(0): [KMS] drm report modesetting isn't supported.
[    15.550] (EE) Screen 0 deleted because of no matching config section.
[    15.550] (II) UnloadModule: "amdgpu"
[    15.550] (EE) Device(s) detected, but none match those in the config file.
[    15.550] (EE) 
Fatal server error:
[    15.550] (EE) no screens found(EE) 

Last edited by toru (2020-06-13 22:53:13)

Offline

#8 2020-06-13 23:05:35

Head_on_a_Stick
Member
From: London
Registered: 2019-03-24
Posts: 3,125  
Website

Re: Backlight control problem

toru wrote:

What happened with nano:
brightness:  [ Error writing lock file /sys/class/backlight/acpi_video0/.brightness.swp: Permission denied ]
max_brightness:  [ File '/sys/class/backlight/acpi_video0/max_brightness' is unwritable ]
actual_brightness:  [ File '/sys/class/backlight/acpi_video0/actual_brightness' is unwritable ]

Looks like nano was trying to write to a backup for the brightness file, not sure why. It works on my system if I ensure that it's saving to the actual backlight file.

Note that the max_brightness and actual_brightness files can't be changed so that result is expected (sysfs doesn't work like normal filesystems, it is virtual in nature and just exposes kernel values to user space).

No idea why my tee & echo suggestions didn't work though. At a guess it's because you don't have a kernel module loaded for your video card.

toru wrote:

And if I must, I will try firmware-amd-graphics.  I wish to avoid proprietary software if possible, but if there's no other way.

You're already loading non-free firmware from Devuan for your Intel wireless card. Your UEFI firmware, CPU management engine and hard drive controller are all running blobs anyway. There is no escape...

toru wrote:

Also, I found this.  Do you think this could solve my problem?  https://cannibalcandy.wordpress.com/201 … acpi-woes/

That's an interesting find but I'm pretty sure that the backlight will be controllable once you have a video driver loaded.

toru wrote:

Oh, also it looks like the same thing happened again with the amdgpu modification to 10-backlight.conf:

[    15.550] (II) AMDGPU(0): [KMS] drm report modesetting isn't supported.

AMD cards require KMS and that needs a kernel driver.


Brianna Ghey — Rest In Power

Offline

#9 2020-06-13 23:31:37

ralph.ronnquist
Administrator
From: Clifton Hill, Victoria, AUS
Registered: 2016-11-30
Posts: 1,106  

Re: Backlight control problem

@toru, what does cat /sys/class/backlight/acpi_video0/max_brightness say?

Presumably something less than 100, as according to your post #7, the complaint was about the value, not the writing.

If that's the case, you should try again with @Head_on_a_Stick's tee method and a number between 0 and that maximal number. Ideally half of max should result in 50% brightness.

Offline

#10 2020-06-14 16:22:38

toru
Member
Registered: 2020-04-12
Posts: 26  

Re: Backlight control problem

radeon.cik_support=0 amdgpu.cik_support=1

The computer booted and went to the login manager and let me login and such.  But the backlight slider still doesn't let me change the backlight brightness.  Maybe, nothing that I noticed changed.
I say maybe because I became able to use the backlight function keys at some point, but it doesn't actually change the backlight.  Could be that those kernel command line parameters changed this, but I would have to test that.

what does cat /sys/class/backlight/acpi_video0/max_brightness say?

$ sudo cat /sys/class/backlight/acpi_video0/max_brightness
10

Presumably something less than 100, as according to your post #7, the complaint was about the value, not the writing.

If that's the case, you should try again with @Head_on_a_Stick's tee method and a number between 0 and that maximal number. Ideally half of max should result in 50% brightness.

$ sudo tee /sys/class/backlight/acpi_video0/brightness <<<'5'
5
$ sudo tee /sys/class/backlight/acpi_video0/brightness <<<'0'
0
$ sudo cat /sys/class/backlight/acpi_video0/brightness
0

Modifying the file in this way works but it doesn't change the brightness of the screen.  Oh, and thank you for the help!

Note that the max_brightness and actual_brightness files can't be changed so that result is expected (sysfs doesn't work like normal filesystems, it is virtual in nature and just exposes kernel values to user space).

Ohhhh!  Thanks for letting me know, this makes sense now.

No idea why my tee & echo suggestions didn't work though. At a guess it's because you don't have a kernel module loaded for your video card.

Hmmmm so it is sounding like I MIGHT not be able to escape installing that proprietary driver.  But I'm still going to look into other options for the backlight.  Also, thank you again for the help.

You're already loading non-free firmware from Devuan for your Intel wireless card. Your UEFI firmware, CPU management engine and hard drive controller are all running blobs anyway. There is no escape...

This exists:  https://github.com/corna/me_cleaner
Also I am currently not using my wireless card, I just have the package around in case I need to use the card.  LAN often suits my purposes.
For BIOS and UEFI firmware - fair enough.  However, though I don't have it on this computer, https://libreboot.org/ exists.
Hard drive controller?  That seems to be one I didn't know about.  I would be quite interested to hear more about that.

Anyway, it is still a virtue to take steps to get rid of, if not the entire problem, then parts of the problem.  And who knows, maybe you can even get rid of the entire problem...

And now I guess I'll try firmware-amd-graphics.
...Both the non-backports version (20190114-2) and the beowulf-backports version (20190717-2~bpo10+1) fixed the backlight problem but then introduced another problem.  I tried to load Caja and the display glitched hard, distorting the windows to the point of the system being unusable.  tty1 worked fine still.  I tried to screenshot the problem but in the screenshots the problem isn't there.  I was able to take screenshots by just pressing prtsc and hitting enter.

To me, this doesn't seem very helpful:  (Xorg.0.log)

[    15.059] xorg-server 2:1.20.4-1 (https://www.debian.org/support) 
[    15.059] Current version of pixman: 0.36.0
[    15.059] 	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
[    15.059] Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[    15.059] (==) Log file: "/var/log/Xorg.0.log", Time: Sun Jun 14 11:54:10 2020
[    15.132] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[    15.202] (==) No Layout section.  Using the first Screen section.
[    15.202] (==) No screen section available. Using defaults.
[    15.202] (**) |-->Screen "Default Screen Section" (0)
[    15.202] (**) |   |-->Monitor "<default monitor>"
[    15.218] (==) No monitor specified for screen "Default Screen Section".
	Using a default monitor configuration.
[    15.218] (==) Automatically adding devices
[    15.219] (==) Automatically enabling devices
[    15.219] (==) Automatically adding GPU devices
[    15.219] (==) Max clients allowed: 256, resource mask: 0x1fffff
[    15.504] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist.
[    15.504] 	Entry deleted from font path.
[    15.517] (==) FontPath set to:
	/usr/share/fonts/X11/misc,
	/usr/share/fonts/X11/100dpi/:unscaled,
	/usr/share/fonts/X11/75dpi/:unscaled,
	/usr/share/fonts/X11/Type1,
	/usr/share/fonts/X11/100dpi,
	/usr/share/fonts/X11/75dpi,
	built-ins
[    15.517] (==) ModulePath set to "/usr/lib/xorg/modules"
[    15.517] (II) The server relies on udev to provide the list of input devices.
	If no devices become available, reconfigure udev or disable AutoAddDevices.
[    15.517] (II) Loader magic: 0x55690ef06e20
[    15.517] (II) Module ABI versions:
[    15.517] 	X.Org ANSI C Emulation: 0.4
[    15.517] 	X.Org Video Driver: 24.0
[    15.517] 	X.Org XInput driver : 24.1
[    15.517] 	X.Org Server Extension : 10.0
[    15.518] (++) using VT number 7

[    15.518] (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
[    15.519] (II) xfree86: Adding drm device (/dev/dri/card0)
[    15.533] (--) PCI:*(0@0:1:0) 1002:98e4:1025:1192 rev 218, Mem @ 0xe0000000/268435456, 0xf0000000/8388608, 0xf0d00000/262144, I/O @ 0x00003000/256, BIOS @ 0x????????/131072
[    15.533] (II) LoadModule: "glx"
[    15.624] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[    15.854] (II) Module glx: vendor="X.Org Foundation"
[    15.854] 	compiled for 1.20.4, module version = 1.0.0
[    15.854] 	ABI class: X.Org Server Extension, version 10.0
[    15.854] (II) Applying OutputClass "AMDgpu" to /dev/dri/card0
[    15.854] 	loading driver: amdgpu
[    15.854] (==) Matched amdgpu as autoconfigured driver 0
[    15.854] (==) Matched ati as autoconfigured driver 1
[    15.854] (==) Matched modesetting as autoconfigured driver 2
[    15.854] (==) Matched fbdev as autoconfigured driver 3
[    15.854] (==) Matched vesa as autoconfigured driver 4
[    15.854] (==) Assigned the driver to the xf86ConfigLayout
[    15.854] (II) LoadModule: "amdgpu"
[    15.854] (II) Loading /usr/lib/xorg/modules/drivers/amdgpu_drv.so
[    16.133] (II) Module amdgpu: vendor="X.Org Foundation"
[    16.133] 	compiled for 1.20.3, module version = 18.1.99
[    16.133] 	Module class: X.Org Video Driver
[    16.133] 	ABI class: X.Org Video Driver, version 24.0
[    16.133] (II) LoadModule: "ati"
[    16.133] (II) Loading /usr/lib/xorg/modules/drivers/ati_drv.so
[    16.151] (II) Module ati: vendor="X.Org Foundation"
[    16.151] 	compiled for 1.20.4, module version = 19.0.1
[    16.151] 	Module class: X.Org Video Driver
[    16.151] 	ABI class: X.Org Video Driver, version 24.0
[    16.181] (II) LoadModule: "modesetting"
[    16.181] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[    16.336] (II) Module modesetting: vendor="X.Org Foundation"
[    16.336] 	compiled for 1.20.4, module version = 1.20.4
[    16.336] 	Module class: X.Org Video Driver
[    16.336] 	ABI class: X.Org Video Driver, version 24.0
[    16.336] (II) LoadModule: "fbdev"
[    16.337] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so
[    16.350] (II) Module fbdev: vendor="X.Org Foundation"
[    16.350] 	compiled for 1.20.0, module version = 0.5.0
[    16.351] 	Module class: X.Org Video Driver
[    16.351] 	ABI class: X.Org Video Driver, version 24.0
[    16.351] (II) LoadModule: "vesa"
[    16.351] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[    16.352] (II) Module vesa: vendor="X.Org Foundation"
[    16.352] 	compiled for 1.20.1, module version = 2.4.0
[    16.352] 	Module class: X.Org Video Driver
[    16.352] 	ABI class: X.Org Video Driver, version 24.0
[    16.352] (II) AMDGPU: Driver for AMD Radeon:
	All GPUs supported by the amdgpu kernel driver
[    16.352] (II) modesetting: Driver for Modesetting Kernel Drivers: kms
[    16.352] (II) FBDEV: driver for framebuffer: fbdev
[    16.352] (II) VESA: driver for VESA chipsets: vesa
[    16.368] (II) AMDGPU(0): [KMS] Kernel modesetting enabled.
[    16.453] (WW) Falling back to old probe method for modesetting
[    16.453] (WW) Falling back to old probe method for fbdev
[    16.453] (II) Loading sub module "fbdevhw"
[    16.453] (II) LoadModule: "fbdevhw"
[    16.453] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so
[    16.681] (II) Module fbdevhw: vendor="X.Org Foundation"
[    16.681] 	compiled for 1.20.4, module version = 0.0.2
[    16.681] 	ABI class: X.Org Video Driver, version 24.0
[    16.681] (II) AMDGPU(0): Creating default Display subsection in Screen section
	"Default Screen Section" for depth/fbbpp 24/32
[    16.681] (==) AMDGPU(0): Depth 24, (--) framebuffer bpp 32
[    16.682] (II) AMDGPU(0): Pixel depth = 24 bits stored in 4 bytes (32 bpp pixmaps)
[    16.682] (==) AMDGPU(0): Default visual is TrueColor
[    16.682] (==) AMDGPU(0): RGB weight 888
[    16.682] (II) AMDGPU(0): Using 8 bits per RGB (8 bit DAC)
[    16.682] (--) AMDGPU(0): Chipset: "Unknown AMD Radeon GPU" (ChipID = 0x98e4)
[    16.682] (II) Loading sub module "fb"
[    16.682] (II) LoadModule: "fb"
[    16.682] (II) Loading /usr/lib/xorg/modules/libfb.so
[    16.734] (II) Module fb: vendor="X.Org Foundation"
[    16.734] 	compiled for 1.20.4, module version = 1.0.0
[    16.734] 	ABI class: X.Org ANSI C Emulation, version 0.4
[    16.734] (II) Loading sub module "dri2"
[    16.734] (II) LoadModule: "dri2"
[    16.734] (II) Module "dri2" already built-in
[    20.182] (II) Loading sub module "glamoregl"
[    20.182] (II) LoadModule: "glamoregl"
[    20.182] (II) Loading /usr/lib/xorg/modules/libglamoregl.so
[    20.226] (II) Module glamoregl: vendor="X.Org Foundation"
[    20.226] 	compiled for 1.20.4, module version = 1.0.1
[    20.226] 	ABI class: X.Org ANSI C Emulation, version 0.4
[    20.464] (II) AMDGPU(0): glamor X acceleration enabled on AMD STONEY (DRM 3.27.0, 4.19.0-9-amd64, LLVM 7.0.1)
[    20.464] (II) AMDGPU(0): glamor detected, initialising EGL layer.
[    20.464] (==) AMDGPU(0): TearFree property default: auto
[    20.464] (==) AMDGPU(0): VariableRefresh: disabled
[    20.464] (II) AMDGPU(0): KMS Pageflipping: enabled
[    20.465] (II) AMDGPU(0): Output eDP has no monitor section
[    20.465] (II) AMDGPU(0): Output HDMI-A-0 has no monitor section
[    20.465] (II) AMDGPU(0): Output DisplayPort-0 has no monitor section
[    20.480] (WW) AMDGPU(0): 3 ZaphodHeads crtcs unavailable. Some outputs will stay off.
[    20.480] (II) AMDGPU(0): EDID for output eDP
[    20.480] (II) AMDGPU(0): Manufacturer: AUO  Model: 70ec  Serial#: 0
[    20.480] (II) AMDGPU(0): Year: 2015  Week: 1
[    20.480] (II) AMDGPU(0): EDID Version: 1.4
[    20.480] (II) AMDGPU(0): Digital Display Input
[    20.480] (II) AMDGPU(0): 6 bits per channel
[    20.480] (II) AMDGPU(0): Digital interface is DisplayPort
[    20.480] (II) AMDGPU(0): Max Image Size [cm]: horiz.: 34  vert.: 19
[    20.480] (II) AMDGPU(0): Gamma: 2.20
[    20.480] (II) AMDGPU(0): No DPMS capabilities specified
[    20.480] (II) AMDGPU(0): Supported color encodings: RGB 4:4:4 
[    20.480] (II) AMDGPU(0): First detailed timing is preferred mode
[    20.480] (II) AMDGPU(0): Preferred mode is native pixel format and refresh rate
[    20.480] (II) AMDGPU(0): redX: 0.575 redY: 0.345   greenX: 0.340 greenY: 0.570
[    20.480] (II) AMDGPU(0): blueX: 0.160 blueY: 0.135   whiteX: 0.313 whiteY: 0.329
[    20.480] (II) AMDGPU(0): Manufacturer's mask: 0
[    20.480] (II) AMDGPU(0): Supported detailed timing:
[    20.480] (II) AMDGPU(0): clock: 76.3 MHz   Image Size:  344 x 193 mm
[    20.480] (II) AMDGPU(0): h_active: 1366  h_sync: 1374  h_sync_end 1384 h_blank_end 1558 h_border: 0
[    20.480] (II) AMDGPU(0): v_active: 768  v_sync: 771  v_sync_end 772 v_blanking: 816 v_border: 0
[    20.480] (II) AMDGPU(0): Unknown vendor-specific block f
[    20.480] (II) AMDGPU(0):  AUO
[    20.480] (II) AMDGPU(0):  B156XTN07.0
[    20.480] (II) AMDGPU(0): EDID (in hex):
[    20.480] (II) AMDGPU(0): 	00ffffffffffff0006afec7000000000
[    20.480] (II) AMDGPU(0): 	01190104952213780250259358579229
[    20.480] (II) AMDGPU(0): 	22505400000001010101010101010101
[    20.480] (II) AMDGPU(0): 	010101010101ce1d56c050003030080a
[    20.480] (II) AMDGPU(0): 	310058c1100000180000000f00000000
[    20.480] (II) AMDGPU(0): 	00000000000000000020000000fe0041
[    20.480] (II) AMDGPU(0): 	554f0a202020202020202020000000fe
[    20.480] (II) AMDGPU(0): 	004231353658544e30372e30200a0014
[    20.480] (II) AMDGPU(0): Printing probed modes for output eDP
[    20.480] (II) AMDGPU(0): Modeline "1366x768"x60.0   76.30  1366 1374 1384 1558  768 771 772 816 -hsync -vsync (49.0 kHz eP)
[    20.480] (II) AMDGPU(0): Modeline "1280x720"x60.0   76.30  1280 1374 1384 1558  720 771 772 816 -hsync -vsync (49.0 kHz e)
[    20.480] (II) AMDGPU(0): Modeline "1024x768"x60.0   76.30  1024 1374 1384 1558  768 771 772 816 -hsync -vsync (49.0 kHz e)
[    20.480] (II) AMDGPU(0): Modeline "800x600"x60.0   76.30  800 1374 1384 1558  600 771 772 816 -hsync -vsync (49.0 kHz e)
[    20.480] (II) AMDGPU(0): Modeline "640x480"x60.0   76.30  640 1374 1384 1558  480 771 772 816 -hsync -vsync (49.0 kHz e)
[    20.480] (II) AMDGPU(0): EDID for output HDMI-A-0
[    20.480] (II) AMDGPU(0): EDID for output DisplayPort-0
[    20.480] (II) AMDGPU(0): Output eDP connected
[    20.480] (II) AMDGPU(0): Output HDMI-A-0 disconnected
[    20.480] (II) AMDGPU(0): Output DisplayPort-0 disconnected
[    20.480] (II) AMDGPU(0): Using exact sizes for initial modes
[    20.480] (II) AMDGPU(0): Output eDP using initial mode 1366x768 +0+0
[    20.480] (II) AMDGPU(0): mem size init: gart size :bf89c000 vram size: s:1777a000 visible:1777a000
[    20.480] (==) AMDGPU(0): DPI set to (96, 96)
[    20.480] (==) AMDGPU(0): Using gamma correction (1.0, 1.0, 1.0)
[    20.480] (II) Loading sub module "ramdac"
[    20.480] (II) LoadModule: "ramdac"
[    20.480] (II) Module "ramdac" already built-in
[    20.480] (II) UnloadModule: "modesetting"
[    20.480] (II) Unloading modesetting
[    20.480] (II) UnloadModule: "fbdev"
[    20.481] (II) Unloading fbdev
[    20.481] (II) UnloadSubModule: "fbdevhw"
[    20.481] (II) Unloading fbdevhw
[    20.481] (II) UnloadModule: "vesa"
[    20.481] (II) Unloading vesa
[    20.525] (II) AMDGPU(0): [DRI2] Setup complete
[    20.525] (II) AMDGPU(0): [DRI2]   DRI driver: radeonsi
[    20.525] (II) AMDGPU(0): [DRI2]   VDPAU driver: radeonsi
[    20.525] (II) AMDGPU(0): Front buffer pitch: 5504 bytes
[    20.555] (II) AMDGPU(0): SYNC extension fences enabled
[    20.556] (II) AMDGPU(0): Present extension enabled
[    20.556] (==) AMDGPU(0): DRI3 enabled
[    20.556] (==) AMDGPU(0): Backing store enabled
[    20.556] (II) AMDGPU(0): Direct rendering enabled
[    20.858] (II) AMDGPU(0): Use GLAMOR acceleration.
[    20.858] (II) AMDGPU(0): Acceleration enabled
[    20.858] (==) AMDGPU(0): DPMS enabled
[    20.858] (==) AMDGPU(0): Silken mouse enabled
[    20.859] (II) AMDGPU(0): Set up textured video (glamor)
[    20.897] (II) Initializing extension Generic Event Extension
[    20.897] (II) Initializing extension SHAPE
[    20.897] (II) Initializing extension MIT-SHM
[    20.897] (II) Initializing extension XInputExtension
[    20.898] (II) Initializing extension XTEST
[    20.898] (II) Initializing extension BIG-REQUESTS
[    20.898] (II) Initializing extension SYNC
[    20.898] (II) Initializing extension XKEYBOARD
[    20.898] (II) Initializing extension XC-MISC
[    20.898] (II) Initializing extension SECURITY
[    20.899] (II) Initializing extension XFIXES
[    20.899] (II) Initializing extension RENDER
[    20.899] (II) Initializing extension RANDR
[    20.899] (II) Initializing extension COMPOSITE
[    20.899] (II) Initializing extension DAMAGE
[    20.899] (II) Initializing extension MIT-SCREEN-SAVER
[    20.900] (II) Initializing extension DOUBLE-BUFFER
[    20.900] (II) Initializing extension RECORD
[    20.900] (II) Initializing extension DPMS
[    20.900] (II) Initializing extension Present
[    20.900] (II) Initializing extension DRI3
[    20.900] (II) Initializing extension X-Resource
[    20.900] (II) Initializing extension XVideo
[    20.900] (II) Initializing extension XVideo-MotionCompensation
[    20.900] (II) Initializing extension SELinux
[    20.900] (II) SELinux: Disabled on system
[    20.900] (II) Initializing extension GLX
[    20.906] (II) AIGLX: Loaded and initialized radeonsi
[    20.906] (II) GLX: Initialized DRI2 GL provider for screen 0
[    20.906] (II) Initializing extension XFree86-VidModeExtension
[    20.906] (II) Initializing extension XFree86-DGA
[    20.906] (II) Initializing extension XFree86-DRI
[    20.906] (II) Initializing extension DRI2
[    20.908] (II) AMDGPU(0): Setting screen physical size to 361 x 203
[    22.016] (II) config/udev: Adding input device Power Button (/dev/input/event5)
[    22.016] (**) Power Button: Applying InputClass "libinput keyboard catchall"
[    22.016] (II) LoadModule: "libinput"
[    22.016] (II) Loading /usr/lib/xorg/modules/input/libinput_drv.so
[    22.067] (II) Module libinput: vendor="X.Org Foundation"
[    22.068] 	compiled for 1.20.4, module version = 0.28.2
[    22.068] 	Module class: X.Org XInput Driver
[    22.068] 	ABI class: X.Org XInput driver, version 24.1
[    22.068] (II) Using input driver 'libinput' for 'Power Button'
[    22.068] (**) Power Button: always reports core events
[    22.068] (**) Option "Device" "/dev/input/event5"
[    22.068] (**) Option "_source" "server/udev"
[    22.125] (II) event5  - Power Button: is tagged by udev as: Keyboard
[    22.125] (II) event5  - Power Button: device is a keyboard
[    22.125] (II) event5  - Power Button: device removed
[    22.160] (**) Option "config_info" "udev:/sys/devices/LNXSYSTM:00/LNXPWRBN:00/input/input8/event5"
[    22.160] (II) XINPUT: Adding extended input device "Power Button" (type: KEYBOARD, id 6)
[    22.160] (**) Option "xkb_model" "pc105"
[    22.160] (**) Option "xkb_layout" "us"
[    22.162] (II) event5  - Power Button: is tagged by udev as: Keyboard
[    22.162] (II) event5  - Power Button: device is a keyboard
[    22.162] (II) config/udev: Adding input device Video Bus (/dev/input/event1)
[    22.162] (**) Video Bus: Applying InputClass "libinput keyboard catchall"
[    22.162] (II) Using input driver 'libinput' for 'Video Bus'
[    22.162] (**) Video Bus: always reports core events
[    22.162] (**) Option "Device" "/dev/input/event1"
[    22.162] (**) Option "_source" "server/udev"
[    22.164] (II) event1  - Video Bus: is tagged by udev as: Keyboard
[    22.164] (II) event1  - Video Bus: device is a keyboard
[    22.164] (II) event1  - Video Bus: device removed
[    22.200] (**) Option "config_info" "udev:/sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/LNXVIDEO:00/input/input4/event1"
[    22.200] (II) XINPUT: Adding extended input device "Video Bus" (type: KEYBOARD, id 7)
[    22.200] (**) Option "xkb_model" "pc105"
[    22.200] (**) Option "xkb_layout" "us"
[    22.201] (II) event1  - Video Bus: is tagged by udev as: Keyboard
[    22.202] (II) event1  - Video Bus: device is a keyboard
[    22.202] (II) config/udev: Adding input device Power Button (/dev/input/event2)
[    22.202] (**) Power Button: Applying InputClass "libinput keyboard catchall"
[    22.202] (II) Using input driver 'libinput' for 'Power Button'
[    22.202] (**) Power Button: always reports core events
[    22.202] (**) Option "Device" "/dev/input/event2"
[    22.202] (**) Option "_source" "server/udev"
[    22.203] (II) event2  - Power Button: is tagged by udev as: Keyboard
[    22.203] (II) event2  - Power Button: device is a keyboard
[    22.203] (II) event2  - Power Button: device removed
[    22.232] (**) Option "config_info" "udev:/sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0C:00/input/input5/event2"
[    22.232] (II) XINPUT: Adding extended input device "Power Button" (type: KEYBOARD, id 8)
[    22.232] (**) Option "xkb_model" "pc105"
[    22.232] (**) Option "xkb_layout" "us"
[    22.233] (II) event2  - Power Button: is tagged by udev as: Keyboard
[    22.233] (II) event2  - Power Button: device is a keyboard
[    22.234] (II) config/udev: Adding input device Lid Switch (/dev/input/event4)
[    22.234] (II) No input driver specified, ignoring this device.
[    22.234] (II) This device may have been added with another device file.
[    22.234] (II) config/udev: Adding input device Sleep Button (/dev/input/event3)
[    22.234] (**) Sleep Button: Applying InputClass "libinput keyboard catchall"
[    22.234] (II) Using input driver 'libinput' for 'Sleep Button'
[    22.234] (**) Sleep Button: always reports core events
[    22.234] (**) Option "Device" "/dev/input/event3"
[    22.235] (**) Option "_source" "server/udev"
[    22.236] (II) event3  - Sleep Button: is tagged by udev as: Keyboard
[    22.236] (II) event3  - Sleep Button: device is a keyboard
[    22.236] (II) event3  - Sleep Button: device removed
[    22.276] (**) Option "config_info" "udev:/sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0E:00/input/input6/event3"
[    22.276] (II) XINPUT: Adding extended input device "Sleep Button" (type: KEYBOARD, id 9)
[    22.276] (**) Option "xkb_model" "pc105"
[    22.276] (**) Option "xkb_layout" "us"
[    22.277] (II) event3  - Sleep Button: is tagged by udev as: Keyboard
[    22.277] (II) event3  - Sleep Button: device is a keyboard
[    22.278] (II) config/udev: Adding input device HDA ATI HDMI HDMI/DP,pcm=3 (/dev/input/event7)
[    22.278] (II) No input driver specified, ignoring this device.
[    22.278] (II) This device may have been added with another device file.
[    22.279] (II) config/udev: Adding input device HDA Digital PCBeep (/dev/input/event9)
[    22.279] (II) No input driver specified, ignoring this device.
[    22.279] (II) This device may have been added with another device file.
[    22.279] (II) config/udev: Adding input device HD-Audio Generic Front Headphone (/dev/input/event10)
[    22.279] (II) No input driver specified, ignoring this device.
[    22.279] (II) This device may have been added with another device file.
[    22.280] (II) config/udev: Adding input device VGA WebCam: VGA WebCam (/dev/input/event12)
[    22.280] (**) VGA WebCam: VGA WebCam: Applying InputClass "libinput keyboard catchall"
[    22.280] (II) Using input driver 'libinput' for 'VGA WebCam: VGA WebCam'
[    22.280] (**) VGA WebCam: VGA WebCam: always reports core events
[    22.280] (**) Option "Device" "/dev/input/event12"
[    22.280] (**) Option "_source" "server/udev"
[    22.281] (II) event12 - VGA WebCam: VGA WebCam: is tagged by udev as: Keyboard
[    22.281] (II) event12 - VGA WebCam: VGA WebCam: device is a keyboard
[    22.281] (II) event12 - VGA WebCam: VGA WebCam: device removed
[    22.316] (**) Option "config_info" "udev:/sys/devices/pci0000:00/0000:00:12.0/usb3/3-1/3-1.4/3-1.4:1.0/input/input17/event12"
[    22.316] (II) XINPUT: Adding extended input device "VGA WebCam: VGA WebCam" (type: KEYBOARD, id 10)
[    22.316] (**) Option "xkb_model" "pc105"
[    22.316] (**) Option "xkb_layout" "us"
[    22.318] (II) event12 - VGA WebCam: VGA WebCam: is tagged by udev as: Keyboard
[    22.318] (II) event12 - VGA WebCam: VGA WebCam: device is a keyboard
[    22.319] (II) config/udev: Adding input device SYNA7DB5:00 06CB:7DB7 Touchpad (/dev/input/event8)
[    22.319] (**) SYNA7DB5:00 06CB:7DB7 Touchpad: Applying InputClass "libinput touchpad catchall"
[    22.319] (II) Using input driver 'libinput' for 'SYNA7DB5:00 06CB:7DB7 Touchpad'
[    22.319] (**) SYNA7DB5:00 06CB:7DB7 Touchpad: always reports core events
[    22.319] (**) Option "Device" "/dev/input/event8"
[    22.319] (**) Option "_source" "server/udev"
[    22.321] (II) event8  - SYNA7DB5:00 06CB:7DB7 Touchpad: is tagged by udev as: Touchpad
[    22.322] (II) event8  - SYNA7DB5:00 06CB:7DB7 Touchpad: device is a touchpad
[    22.322] (II) event8  - SYNA7DB5:00 06CB:7DB7 Touchpad: device removed
[    22.364] (**) Option "config_info" "udev:/sys/devices/platform/AMD0010:00/i2c-0/i2c-SYNA7DB5:00/0018:06CB:7DB7.0001/input/input12/event8"
[    22.364] (II) XINPUT: Adding extended input device "SYNA7DB5:00 06CB:7DB7 Touchpad" (type: TOUCHPAD, id 11)
[    22.366] (**) Option "AccelerationScheme" "none"
[    22.366] (**) SYNA7DB5:00 06CB:7DB7 Touchpad: (accel) selected scheme none/0
[    22.366] (**) SYNA7DB5:00 06CB:7DB7 Touchpad: (accel) acceleration factor: 2.000
[    22.366] (**) SYNA7DB5:00 06CB:7DB7 Touchpad: (accel) acceleration threshold: 4
[    22.368] (II) event8  - SYNA7DB5:00 06CB:7DB7 Touchpad: is tagged by udev as: Touchpad
[    22.369] (II) event8  - SYNA7DB5:00 06CB:7DB7 Touchpad: device is a touchpad
[    22.370] (II) config/udev: Adding input device SYNA7DB5:00 06CB:7DB7 Touchpad (/dev/input/mouse0)
[    22.370] (II) No input driver specified, ignoring this device.
[    22.370] (II) This device may have been added with another device file.
[    22.370] (II) config/udev: Adding input device AT Translated Set 2 keyboard (/dev/input/event0)
[    22.370] (**) AT Translated Set 2 keyboard: Applying InputClass "libinput keyboard catchall"
[    22.370] (II) Using input driver 'libinput' for 'AT Translated Set 2 keyboard'
[    22.370] (**) AT Translated Set 2 keyboard: always reports core events
[    22.370] (**) Option "Device" "/dev/input/event0"
[    22.370] (**) Option "_source" "server/udev"
[    22.371] (II) event0  - AT Translated Set 2 keyboard: is tagged by udev as: Keyboard
[    22.371] (II) event0  - AT Translated Set 2 keyboard: device is a keyboard
[    22.372] (II) event0  - AT Translated Set 2 keyboard: device removed
[    22.404] (**) Option "config_info" "udev:/sys/devices/platform/i8042/serio0/input/input0/event0"
[    22.404] (II) XINPUT: Adding extended input device "AT Translated Set 2 keyboard" (type: KEYBOARD, id 12)
[    22.404] (**) Option "xkb_model" "pc105"
[    22.404] (**) Option "xkb_layout" "us"
[    22.405] (II) event0  - AT Translated Set 2 keyboard: is tagged by udev as: Keyboard
[    22.405] (II) event0  - AT Translated Set 2 keyboard: device is a keyboard
[    22.407] (II) config/udev: Adding input device PC Speaker (/dev/input/event6)
[    22.407] (II) No input driver specified, ignoring this device.
[    22.407] (II) This device may have been added with another device file.
[    22.407] (II) config/udev: Adding input device Acer WMI hotkeys (/dev/input/event11)
[    22.407] (**) Acer WMI hotkeys: Applying InputClass "libinput keyboard catchall"
[    22.407] (II) Using input driver 'libinput' for 'Acer WMI hotkeys'
[    22.407] (**) Acer WMI hotkeys: always reports core events
[    22.407] (**) Option "Device" "/dev/input/event11"
[    22.407] (**) Option "_source" "server/udev"
[    22.408] (II) event11 - Acer WMI hotkeys: is tagged by udev as: Keyboard
[    22.408] (II) event11 - Acer WMI hotkeys: device is a keyboard
[    22.408] (II) event11 - Acer WMI hotkeys: device removed
[    22.444] (**) Option "config_info" "udev:/sys/devices/virtual/input/input16/event11"
[    22.444] (II) XINPUT: Adding extended input device "Acer WMI hotkeys" (type: KEYBOARD, id 13)
[    22.444] (**) Option "xkb_model" "pc105"
[    22.444] (**) Option "xkb_layout" "us"
[    22.445] (II) event11 - Acer WMI hotkeys: is tagged by udev as: Keyboard
[    22.445] (II) event11 - Acer WMI hotkeys: device is a keyboard
[    34.517] (II) AMDGPU(0): EDID vendor "AUO", prod id 28908
[    34.517] (II) AMDGPU(0): Printing DDC gathered Modelines:
[    34.517] (II) AMDGPU(0): Modeline "1366x768"x0.0   76.30  1366 1374 1384 1558  768 771 772 816 -hsync -vsync (49.0 kHz eP)
[    34.518] (II) AMDGPU(0): EDID vendor "AUO", prod id 28908
[    34.518] (II) AMDGPU(0): Printing DDC gathered Modelines:
[    34.518] (II) AMDGPU(0): Modeline "1366x768"x0.0   76.30  1366 1374 1384 1558  768 771 772 816 -hsync -vsync (49.0 kHz eP)
[    34.521] (II) AMDGPU(0): EDID vendor "AUO", prod id 28908
[    34.521] (II) AMDGPU(0): Printing DDC gathered Modelines:
[    34.521] (II) AMDGPU(0): Modeline "1366x768"x0.0   76.30  1366 1374 1384 1558  768 771 772 816 -hsync -vsync (49.0 kHz eP)
[    34.522] (II) AMDGPU(0): EDID vendor "AUO", prod id 28908
[    34.522] (II) AMDGPU(0): Printing DDC gathered Modelines:
[    34.522] (II) AMDGPU(0): Modeline "1366x768"x0.0   76.30  1366 1374 1384 1558  768 771 772 816 -hsync -vsync (49.0 kHz eP)
[    37.387] (II) AMDGPU(0): EDID vendor "AUO", prod id 28908
[    37.387] (II) AMDGPU(0): Printing DDC gathered Modelines:
[    37.387] (II) AMDGPU(0): Modeline "1366x768"x0.0   76.30  1366 1374 1384 1558  768 771 772 816 -hsync -vsync (49.0 kHz eP)
[    61.250] (II) event5  - Power Button: device removed
[    61.284] (II) event1  - Video Bus: device removed
[    61.317] (II) event2  - Power Button: device removed
[    61.349] (II) event3  - Sleep Button: device removed
[    61.381] (II) event12 - VGA WebCam: VGA WebCam: device removed
[    61.413] (II) event8  - SYNA7DB5:00 06CB:7DB7 Touchpad: device removed
[    61.446] (II) event0  - AT Translated Set 2 keyboard: device removed
[    61.485] (II) event11 - Acer WMI hotkeys: device removed
[    61.521] (II) AIGLX: Suspending AIGLX clients for VT switch
[   105.036] (II) UnloadModule: "libinput"
[   105.038] (II) UnloadModule: "libinput"
[   105.038] (II) UnloadModule: "libinput"
[   105.038] (II) UnloadModule: "libinput"
[   105.038] (II) UnloadModule: "libinput"
[   105.038] (II) UnloadModule: "libinput"
[   105.038] (II) UnloadModule: "libinput"
[   105.039] (II) UnloadModule: "libinput"
[   105.048] (II) Server terminated successfully (0). Closing log file.

Last edited by toru (2020-06-14 16:26:02)

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#11 2020-06-14 17:58:24

Head_on_a_Stick
Member
From: London
Registered: 2019-03-24
Posts: 3,125  
Website

Re: Backlight control problem

toru wrote:

so it is sounding like I MIGHT not be able to escape installing that proprietary driver.

Firmware is not the same as driver. Your AMD card will perform very poorly without the firmware.

toru wrote:

Hard drive controller?  That seems to be one I didn't know about.  I would be quite interested to hear more about that.

https://media.kasperskycontenthub.com/w … nswers.pdf

The risk level is very low for that sort of exploit, especially compared to something like Firefox or Chrom{e,ium}, but the motherboard hardware controllers contain blobs and some of them can be rather complex.

toru wrote:

...Both the non-backports version (20190114-2) and the beowulf-backports version (20190717-2~bpo10+1) fixed the backlight problem but then introduced another problem.  I tried to load Caja and the display glitched hard, distorting the windows to the point of the system being unusable.  tty1 worked fine still.  I tried to screenshot the problem but in the screenshots the problem isn't there.  I was able to take screenshots by just pressing prtsc and hitting enter.

Sounds like a compositor issue, check ~/.xsession-errors for clues.

If the backlight problem is now fixed then please mark the thread [SOLVED]. If you want to continue with the screen corruption issue then open a new thread, thanks.


Brianna Ghey — Rest In Power

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#12 2020-06-16 17:14:46

toru
Member
Registered: 2020-04-12
Posts: 26  

Re: Backlight control problem

So, if possible I would still like to attempt to solve this issue without the proprietary firmware.  Specifically I'm only talking about getting the backlight control working in some sense.  Even if it is just something I can only set when rebooting the computer.  That would still at least help.

But if you guys are not willing to handle assisting in that, I will mark the thread closed.

I will try to handle the firmware issue on my own.  If I fail enough, I may make a thread on it.

Thanks for your help all the way either way, even if this may look like an obvious solution that wasn't tried.  To me it isn't exactly a solution, but it can help and it is nice to know and I may use it.  I did not actually know that this package existed.

Last edited by toru (2020-06-16 17:17:30)

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