Package: src:linux Version: 5.8.10-1~bpo10+1 Severity: normal File: linux-image-5.8
Dear Maintainer, On the ASUS T100TA convertible laptop [1], and probably on similar devices with the same Intel Bay Trail chipset as well, the screen backlight cannot be adjusted and it is set to the maximum brightness. It looks like the problem is caused by a failure in controlling the PMIC 'Crystal Cove' of the Intel Bay Trail chipsets family. Relevant messages from journalctl: > oct 10 15:26:51 asus kernel: fb0: switching to inteldrmfb from EFI VGA > oct 10 15:26:51 asus kernel: i915 0000:00:02.0: vgaarb: deactivate vga console > oct 10 15:26:51 asus kernel: [drm] Supports vblank timestamp caching Rev 2 > (21.10.2013). > oct 10 15:26:51 asus kernel: i915 0000:00:02.0: vgaarb: changed VGA decodes: > olddecodes=io+mem,decodes=io+mem:owns=io+mem > oct 10 15:26:51 asus kernel: i915 0000:00:02.0: cannot find GPIO chip > gpio_crystalcove, deferring > oct 10 15:26:51 asus kernel: i915 0000:00:02.0: [drm] *ERROR* Failed to own > gpio for panel control > oct 10 15:26:51 asus kernel: i915 0000:00:02.0: [drm] *ERROR* Failed to get > the PMIC PWM chip > oct 10 15:26:51 asus kernel: [drm] Initialized i915 1.6.0 20200515 for > 0000:00:02.0 on minor 0 > oct 10 15:26:51 asus kernel: i915 0000:00:02.0: [drm] HDaudio controller not > detected, using LPE audio instead > oct 10 15:26:51 asus kernel: fbcon: i915drmfb (fb0) is primary device > oct 10 15:26:51 asus kernel: i915 0000:00:02.0: fb0: i915drmfb frame buffer > device The problem is present in Debian stable using the default Linux kernel 4.9 and the kernel 5.8 from the backports repositories. I found two similar bug reports from other sources: - Backlight init fails on Surface 3 if module load order is wrong [2] - chromeos-5.4: backlight not adjustable #23 [3] If I read them correctly, it appears there might be already some upstream patches addressing this problem. Could you please have a look into it? Cheers [1] https://wiki.debian.org/InstallingDebianOn/Asus/T100TA [2] https://gitlab.freedesktop.org/drm/intel/-/issues/26 [3] https://github.com/kitakar5525/chromeos-kernel-linux-surface/issues/23 -- Package-specific info: ** Version: Linux version 5.8.0-0.bpo.2-amd64 (debian-ker...@lists.debian.org) (gcc-8 (Debian 8.3.0-6) 8.3.0, GNU ld (GNU Binutils for Debian) 2.31.1) #1 SMP Debian 5.8.10-1~bpo10+1 (2020-09-26) ** Command line: BOOT_IMAGE=/vmlinuz-5.8.0-0.bpo.2-amd64 root=/dev/mapper/asus--vg-root ro quiet ** Tainted: W (512) * kernel issued warning ** Kernel log: [ 29.717389] Bluetooth: HCI UART protocol Three-wire (H5) registered [ 29.717499] Bluetooth: HCI UART protocol Intel registered [ 29.717660] Bluetooth: HCI UART protocol Broadcom registered [ 29.717682] Bluetooth: HCI UART protocol QCA registered [ 29.717684] Bluetooth: HCI UART protocol AG6XX registered [ 29.717705] Bluetooth: HCI UART protocol Marvell registered [ 29.737331] hci_uart_bcm serial0-0: ACPI Interrupt resource is active-high, this is usually wrong, treating the IRQ as active-low [ 29.737552] hci_uart_bcm serial0-0: supply vbat not found, using dummy regulator [ 29.737588] hci_uart_bcm serial0-0: supply vddio not found, using dummy regulator [ 29.809317] input: PC Speaker as /devices/platform/pcspkr/input/input19 [ 29.861292] i2c i2c-4: Added multiplexed i2c bus 14 [ 29.877515] EFI Variables Facility v0.08 2004-May-17 [ 29.878530] ak8975 14-000c: mounting matrix not found: using identity... [ 29.878540] ak8975 14-000c: supply vdd not found, using dummy regulator [ 29.878585] ak8975 14-000c: supply vid not found, using dummy regulator [ 29.918897] pstore: Using crash dump compression: deflate [ 29.935053] pstore: Registered efi as persistent store backend [ 30.114856] cfg80211: Loading compiled-in X.509 certificates for regulatory database [ 30.115501] cfg80211: Loaded X.509 cert 'b...@debian.org: 577e021cb980e0e820821ba7b54b4961b8b4fadf' [ 30.116078] cfg80211: Loaded X.509 cert 'romain.per...@gmail.com: 3abbc6ec146e09d1b6016ab9d6cf71dd233f0328' [ 30.116652] cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7' [ 30.134195] platform regulatory.0: firmware: direct-loading firmware regulatory.db [ 30.168580] platform regulatory.0: firmware: direct-loading firmware regulatory.db.p7s [ 30.284604] Bluetooth: hci0: BCM: chip id 84 [ 30.301725] Bluetooth: hci0: BCM: features 0x0f [ 30.319706] Bluetooth: hci0: BCM4324B3 [ 30.319717] Bluetooth: hci0: BCM4324B3 (002.004.006) build 0000 [ 30.322002] bluetooth hci0: firmware: failed to load brcm/BCM4324B3.hcd (-2) [ 30.322098] firmware_class: See https://wiki.debian.org/Firmware for information about missing firmware [ 30.322244] bluetooth hci0: firmware: failed to load brcm/BCM.hcd (-2) [ 30.322320] Bluetooth: hci0: BCM: firmware Patch file not found, tried: [ 30.322394] Bluetooth: hci0: BCM: 'brcm/BCM4324B3.hcd' [ 30.322452] Bluetooth: hci0: BCM: 'brcm/BCM.hcd' [ 30.352555] intel_rapl_common: Found RAPL domain package [ 30.352559] intel_rapl_common: Found RAPL domain core [ 30.383338] mmc1: queuing unknown CIS tuple 0x80 (2 bytes) [ 30.386482] input: gpio-keys as /devices/platform/INTCFD9:00/gpio-keys.1.auto/input/input20 [ 30.389179] mmc1: queuing unknown CIS tuple 0x80 (3 bytes) [ 30.390728] mmc1: queuing unknown CIS tuple 0x80 (3 bytes) [ 30.393499] mmc1: queuing unknown CIS tuple 0x80 (7 bytes) [ 30.515827] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43241b4-sdio for chip BCM4324/5 [ 30.515947] usbcore: registered new interface driver brcmfmac [ 30.524231] brcmfmac mmc1:0001:1: firmware: direct-loading firmware brcm/brcmfmac43241b4-sdio.bin [ 30.524290] brcmfmac mmc1:0001:1: firmware: failed to load brcm/brcmfmac43241b4-sdio.ASUSTeK COMPUTER INC.-T100TA.txt (-2) [ 30.524427] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43241b4-sdio.ASUSTeK COMPUTER INC.-T100TA.txt failed with error -2 [ 30.528984] brcmfmac mmc1:0001:1: firmware: direct-loading firmware brcm/brcmfmac43241b4-sdio.txt [ 30.563863] bytcr_rt5640 bytcr_rt5640: quirk IN1_MAP enabled [ 30.563868] bytcr_rt5640 bytcr_rt5640: quirk realtek,jack-detect-source 3 [ 30.563871] bytcr_rt5640 bytcr_rt5640: quirk realtek,over-current-threshold-microamp 2000 [ 30.563873] bytcr_rt5640 bytcr_rt5640: quirk realtek,over-current-scale-factor 1 [ 30.563876] bytcr_rt5640 bytcr_rt5640: quirk MCLK_EN enabled [ 30.619362] bytcr_rt5640 bytcr_rt5640: snd-soc-dummy-dai <-> media-cpu-dai mapping ok [ 30.619935] bytcr_rt5640 bytcr_rt5640: snd-soc-dummy-dai <-> deepbuffer-cpu-dai mapping ok [ 30.641527] bytcr_rt5640 bytcr_rt5640: rt5640-aif1 <-> ssp2-port mapping ok [ 30.648684] input: bytcr-rt5640 Headset as /devices/platform/80860F28:00/bytcr_rt5640/sound/card1/input21 [ 30.708603] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43241b4-sdio for chip BCM4324/5 [ 30.708670] brcmfmac mmc1:0001:1: firmware: failed to load brcm/brcmfmac43241b4-sdio.clm_blob (-2) [ 30.708786] brcmfmac: brcmf_c_process_clm_blob: no clm_blob available (err=-2), device may have limited channels available [ 30.710216] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM4324/5 wl0: Jul 17 2013 07:36:07 version 6.10.197.71 (r412987) FWID 01-882d2634 [ 30.869962] EXT4-fs (mmcblk2p2): mounting ext2 file system using the ext4 subsystem [ 30.874376] EXT4-fs (mmcblk2p2): mounted filesystem without journal. Opts: (null) [ 30.874399] ext2 filesystem being mounted at /boot supports timestamps until 2038 (0x7fffffff) [ 30.905219] Adding 1982460k swap on /dev/mapper/asus--vg-swap_1. Priority:-2 extents:1 across:1982460k SSFS [ 40.276845] BTRFS: device fsid 8706c28b-48f2-4fe0-85b3-7406de75e896 devid 1 transid 3937 /dev/dm-3 scanned by systemd-udevd (715) [ 40.370927] BTRFS info (device dm-3): use zstd compression, level 3 [ 40.370931] BTRFS info (device dm-3): disk space caching is enabled [ 40.370933] BTRFS info (device dm-3): has skinny extents [ 40.437324] BTRFS info (device dm-3): enabling ssd optimizations [ 40.609657] audit: type=1400 audit(1602336423.023:2): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/sbin/haveged" pid=756 comm="apparmor_parser" [ 40.610372] audit: type=1400 audit(1602336423.023:3): apparmor="STATUS" operation="profile_load" profile="unconfined" name="libreoffice-senddoc" pid=757 comm="apparmor_parser" [ 40.614667] audit: type=1400 audit(1602336423.027:4): apparmor="STATUS" operation="profile_load" profile="unconfined" name="libreoffice-oopslash" pid=755 comm="apparmor_parser" [ 40.623492] audit: type=1400 audit(1602336423.035:5): apparmor="STATUS" operation="profile_load" profile="unconfined" name="libreoffice-xpdfimport" pid=759 comm="apparmor_parser" [ 40.624980] audit: type=1400 audit(1602336423.035:6): apparmor="STATUS" operation="profile_load" profile="unconfined" name="firejail-default" pid=760 comm="apparmor_parser" [ 40.627843] audit: type=1400 audit(1602336423.039:7): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/sbin/cups-browsed" pid=758 comm="apparmor_parser" [ 40.631711] audit: type=1400 audit(1602336423.043:8): apparmor="STATUS" operation="profile_load" profile="unconfined" name="nvidia_modprobe" pid=761 comm="apparmor_parser" [ 40.631721] audit: type=1400 audit(1602336423.043:9): apparmor="STATUS" operation="profile_load" profile="unconfined" name="nvidia_modprobe//kmod" pid=761 comm="apparmor_parser" [ 40.640603] audit: type=1400 audit(1602336423.051:10): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/bin/man" pid=763 comm="apparmor_parser" [ 40.640616] audit: type=1400 audit(1602336423.051:11): apparmor="STATUS" operation="profile_load" profile="unconfined" name="man_filter" pid=763 comm="apparmor_parser" [ 41.222933] zram: Added device: zram0 [ 41.223307] zram: Added device: zram1 [ 41.224858] zram: Added device: zram2 [ 41.225462] zram: Added device: zram3 [ 41.240255] zram0: detected capacity change from 0 to 67108864 [ 41.281158] Adding 65532k swap on /dev/zram0. Priority:100 extents:1 across:65532k SSFS [ 41.282317] zram1: detected capacity change from 0 to 67108864 [ 41.317537] Adding 65532k swap on /dev/zram1. Priority:100 extents:1 across:65532k SSFS [ 41.319534] zram2: detected capacity change from 0 to 67108864 [ 41.357203] Adding 65532k swap on /dev/zram2. Priority:100 extents:1 across:65532k SSFS [ 41.358349] zram3: detected capacity change from 0 to 67108864 [ 41.401206] Adding 65532k swap on /dev/zram3. Priority:100 extents:1 across:65532k SSFS [ 41.451901] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [ 41.451905] Bluetooth: BNEP filters: protocol multicast [ 41.451914] Bluetooth: BNEP socket layer initialized [ 42.646140] broken atomic modeset userspace detected, disabling atomic [ 51.217174] intel_sst_acpi 80860F28:00: FW Version 01.0c.00.01 [ 51.665189] Bluetooth: RFCOMM TTY layer initialized [ 51.665201] Bluetooth: RFCOMM socket layer initialized [ 51.665220] Bluetooth: RFCOMM ver 1.11 [ 1056.034607] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready [ 1056.289680] tun: Universal TUN/TAP device driver, 1.6 ** Model information sys_vendor: ASUSTeK COMPUTER INC. product_name: T100TA product_version: 1.0 chassis_vendor: ASUSTeK COMPUTER INC. chassis_version: 1.0 bios_vendor: American Megatrends Inc. bios_version: T100TA.314 board_vendor: ASUSTeK COMPUTER INC. board_name: T100TA board_version: 1.0 ** Loaded modules: tun rfcomm bnep zram zsmalloc nls_ascii nls_cp437 vfat fat snd_soc_sst_bytcr_rt5640 gpio_keys intel_soc_dts_thermal intel_powerclamp intel_rapl_msr coretemp kvm_intel brcmfmac kvm brcmutil cfg80211 irqbypass efi_pstore intel_cstate ak8975 efivars pcspkr joydev hci_uart sg btqca hid_multitouch btrtl snd_soc_rt5670 btbcm snd_soc_rt5651 btintel bluetooth snd_soc_rt5645 snd_intel_sst_acpi iTCO_wdt snd_intel_sst_core intel_pmc_bxt iTCO_vendor_support snd_hdmi_lpe_audio snd_soc_sst_atom_hifi2_platform jitterentropy_rng snd_soc_rt5640 watchdog snd_soc_acpi_intel_match tpm_crb snd_soc_acpi snd_soc_rl6231 tpm_tis inv_mpu6050_i2c tpm_tis_core snd_soc_core tpm drbg inv_mpu6050 evdev snd_compress industrialio_triggered_buffer rng_core kfifo_buf snd_pcm ansi_cprng soc_button_array processor_thermal_device dptf_power int3406_thermal intel_rapl_common snd_timer int3400_thermal int3403_thermal intel_soc_dts_iosf int340x_thermal_zone acpi_thermal_rel industrialio ecdh_generic intel_int0002_vgpio ecc snd asus_wireless acpi_pad i2c_mux ac soundcore pwm_lpss_platform pwm_lpss parport_pc ppdev lp parport efivarfs ip_tables x_tables autofs4 ext4 crc16 mbcache jbd2 btrfs blake2b_generic xor zstd_decompress zstd_compress raid6_pq libcrc32c crc32c_generic algif_skcipher af_alg sd_mod t10_pi crc_t10dif crct10dif_generic hid_asus asus_wmi sparse_keymap rfkill dm_crypt dm_mod usbhid uas usb_storage scsi_mod hid_generic i915 crct10dif_pclmul crct10dif_common crc32_pclmul crc32c_intel ghash_clmulni_intel mmc_block aesni_intel i2c_algo_bit drm_kms_helper xhci_pci xhci_hcd cec drm libaes crypto_simd cryptd usbcore glue_helper lpc_ich usb_common wmi button video i2c_hid sdhci_acpi dw_dmac hid dw_dmac_core sdhci battery mmc_core ** PCI devices: 00:00.0 Host bridge [0600]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series SoC Transaction Register [8086:0f00] (rev 09) Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series SoC Transaction Register [1043:14ed] Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Kernel driver in use: iosf_mbi_pci 00:02.0 VGA compatible controller [0300]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Graphics & Display [8086:0f31] (rev 09) (prog-if 00 [VGA controller]) Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series Graphics & Display [1043:14ed] Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 37 Region 0: Memory at 90000000 (32-bit, non-prefetchable) [size=4M] Region 2: Memory at 80000000 (32-bit, prefetchable) [size=256M] Region 4: I/O ports at 1000 [size=8] [virtual] Expansion ROM at 000c0000 [disabled] [size=128K] Capabilities: <access denied> Kernel driver in use: i915 Kernel modules: i915 00:14.0 USB controller [0c03]: Intel Corporation Atom Processor Z36xxx/Z37xxx, Celeron N2000 Series USB xHCI [8086:0f35] (rev 09) (prog-if 30 [XHCI]) Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx, Celeron N2000 Series USB xHCI [1043:14ed] Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 35 Region 0: Memory at 90800000 (64-bit, non-prefetchable) [size=64K] Capabilities: <access denied> Kernel driver in use: xhci_hcd Kernel modules: xhci_pci 00:1a.0 Encryption controller [1080]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Trusted Execution Engine [8086:0f18] (rev 09) Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series Trusted Execution Engine [1043:14ed] Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 255 Region 0: Memory at 90700000 (32-bit, non-prefetchable) [size=1M] Region 1: Memory at 90600000 (32-bit, non-prefetchable) [size=1M] Capabilities: <access denied> 00:1f.0 ISA bridge [0601]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Power Control Unit [8086:0f1c] (rev 09) Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series Power Control Unit [1043:14ed] Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Capabilities: <access denied> Kernel driver in use: lpc_ich Kernel modules: lpc_ich ** USB devices: Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 0b05:17e0 ASUSTek Computer, Inc. Bus 001 Device 002: ID 0b05:17e4 ASUSTek Computer, Inc. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub -- System Information: Debian Release: 10.6 APT prefers stable-updates APT policy: (500, 'stable-updates'), (500, 'stable') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 5.8.0-0.bpo.2-amd64 (SMP w/4 CPU cores) Kernel taint flags: TAINT_WARN Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE= (charmap=UTF-8) Shell: /bin/sh linked to /usr/bin/dash Init: systemd (via /run/systemd/system) LSM: AppArmor: enabled Versions of packages linux-image-5.8.0-0.bpo.2-amd64 depends on: ii initramfs-tools [linux-initramfs-tool] 0.133+deb10u1 ii kmod 26-1 ii linux-base 4.6 Versions of packages linux-image-5.8.0-0.bpo.2-amd64 recommends: ii apparmor 2.13.2-10 ii firmware-linux-free 3.4 Versions of packages linux-image-5.8.0-0.bpo.2-amd64 suggests: pn debian-kernel-handbook <none> pn grub-pc | grub-efi-amd64 | extlinux <none> pn linux-doc-5.8 <none> Versions of packages linux-image-5.8.0-0.bpo.2-amd64 is related to: pn firmware-amd-graphics <none> pn firmware-atheros <none> pn firmware-bnx2 <none> pn firmware-bnx2x <none> ii firmware-brcm80211 20190114-2 pn firmware-cavium <none> ii firmware-intel-sound 20190114-2 pn firmware-intelwimax <none> pn firmware-ipw2x00 <none> pn firmware-ivtv <none> pn firmware-iwlwifi <none> pn firmware-libertas <none> pn firmware-linux-nonfree <none> pn firmware-misc-nonfree <none> pn firmware-myricom <none> pn firmware-netxen <none> pn firmware-qlogic <none> pn firmware-realtek <none> pn firmware-samsung <none> pn firmware-siano <none> pn firmware-ti-connectivity <none> pn xen-hypervisor <none> -- no debconf information