If you are using ASUS laptop X513EAN and in Linux kernel logs you have following messages:
i915 0000:00:02.0: drm_WARN_ON(val == 0xffffffff)
mar 08 20:24:30 asus-x513ean kernel: WARNING: CPU: 1 PID: 158 at drivers/gpu/drm/i915/display/intel_tc.c:963 intel_tc_port_init+0x257/0x270 [i915]
mar 08 20:24:30 asus-x513ean kernel: Modules linked in: i915(+) drm_buddy i2c_algo_bit drm_display_helper cec rc_core spi_pxa2xx_platform dw_dmac hid_mult
mar 08 20:24:30 asus-x513ean kernel: CPU: 1 PID: 158 Comm: (udev-worker) Not tainted 6.1.0-29-amd64 #1 Debian 6.1.123-1
mar 08 20:24:30 asus-x513ean kernel: Hardware name: ASUSTeK COMPUTER INC. VivoBook_ASUSLaptop X513EAN_K513EA/X513EAN, BIOS X513EAN.307 04/10/2023
mar 08 20:24:30 asus-x513ean kernel: RIP: 0010:intel_tc_port_init+0x257/0x270 [i915]
(...)
This message is related with initalization of port HDMI-2 in the system which is non existing and is dummmy and in ASUS X513EAN we have only HDMI-1 and build-in screen aka eDP-1 as is reported by xrandr tool in Linux Debian and others. As I do not like errors in the logs I decided that I will turn off initialization of HDMI-2 in the kernel sources because I could not disable it by other way.
So here is my patch (patch-6.18.16-lk.i915mod.patch) applicable on kernel version 6.18.16 by the command patch -d linux-6.18.16 -p2<patch-6.18.16-lk.i915mod.patch
If you preffer compiled kernel for Debian/Ubuntu/etc. I have got ready binaries:
https://kalamlacki.eu/KERNELS/linux-image-6.18.16-lk.i915mod_6.18.16-4_amd64.deb
https://kalamlacki.eu/KERNELS/linux-headers-6.18.16-lk.i915mod_6.18.16-4_amd64.deb
https://kalamlacki.eu/KERNELS/linux-libc-dev_6.18.16-4_amd64.deb
After installing this kernel HDMI-2 port will disappear from xrandr output and you will not longer see disturbing errors in the kernel logs and Linux will skip dummy initialization of HDMI-2.
i915 0000:00:02.0: drm_WARN_ON(val == 0xffffffff)
mar 08 20:24:30 asus-x513ean kernel: WARNING: CPU: 1 PID: 158 at drivers/gpu/drm/i915/display/intel_tc.c:963 intel_tc_port_init+0x257/0x270 [i915]
mar 08 20:24:30 asus-x513ean kernel: Modules linked in: i915(+) drm_buddy i2c_algo_bit drm_display_helper cec rc_core spi_pxa2xx_platform dw_dmac hid_mult
mar 08 20:24:30 asus-x513ean kernel: CPU: 1 PID: 158 Comm: (udev-worker) Not tainted 6.1.0-29-amd64 #1 Debian 6.1.123-1
mar 08 20:24:30 asus-x513ean kernel: Hardware name: ASUSTeK COMPUTER INC. VivoBook_ASUSLaptop X513EAN_K513EA/X513EAN, BIOS X513EAN.307 04/10/2023
mar 08 20:24:30 asus-x513ean kernel: RIP: 0010:intel_tc_port_init+0x257/0x270 [i915]
(...)
This message is related with initalization of port HDMI-2 in the system which is non existing and is dummmy and in ASUS X513EAN we have only HDMI-1 and build-in screen aka eDP-1 as is reported by xrandr tool in Linux Debian and others. As I do not like errors in the logs I decided that I will turn off initialization of HDMI-2 in the kernel sources because I could not disable it by other way.
So here is my patch (patch-6.18.16-lk.i915mod.patch) applicable on kernel version 6.18.16 by the command patch -d linux-6.18.16 -p2<patch-6.18.16-lk.i915mod.patch
If you preffer compiled kernel for Debian/Ubuntu/etc. I have got ready binaries:
https://kalamlacki.eu/KERNELS/linux-image-6.18.16-lk.i915mod_6.18.16-4_amd64.deb
https://kalamlacki.eu/KERNELS/linux-headers-6.18.16-lk.i915mod_6.18.16-4_amd64.deb
https://kalamlacki.eu/KERNELS/linux-libc-dev_6.18.16-4_amd64.deb
After installing this kernel HDMI-2 port will disappear from xrandr output and you will not longer see disturbing errors in the kernel logs and Linux will skip dummy initialization of HDMI-2.