Hello, I understand you may be busy, however, could you please confirm you have
received my request or give me a link to a tracking ticket ?
Sorry for disturbing, and thank you very much
--
Nov 23, 2020, 16:06 by prog-amat...@tutamail.com:
> Hello, the brightness doesn't work (cursor moves but not real brightness).
> Could you please help or at least forward to the relevant member ? Thank you
> very much for your kind help.
> Error message> :Some messages appear during boot (after grub) :
>
> i915 :00:02.0 : [drm] *ERROR* Failed to get the PMIC PWM chip
> i915 :00:02.0 : [drm] *ERROR* [CRTC:51:pipe A] mismatch in pixel_rate
> i915 :00:02.0 : [drm] *ERROR* [CRTC:51:pipe A] mismatch in
> hw_adjusted_mode.crtc_clock
> i915 :00:02.0 : [drm] *ERROR* [CRTC:51:pipe A] mismatch in port_clock
> Information about device and version> : My device is an HP Pro Tablet 608
> (CPU : Intel Atom X5-Z8500, 64 bits, RAM : 4GB)I am using Debian Testing
> GNU/Linux 5.9 (but this bug appears also in 5.8, and Stable version), kernel
> 5.9.0-1-amd64, GNOME 3.38.1 under Wayland.
> Possible solution after test with Fedora (GNOME/Wayland/similar kernel)>
> :Brightness can be controlled fine. It seems that this bug has been already
> fixed in Fedora with patches (c.f. : >
> https://patchwork.freedesktop.org/series/69686/> ). Summary of this patch is
> below :
> "drivers/acpi/acpi_lpss.c and/or driver/mfd/intel_soc_pmic_core.c
> registers a pwm with the generic name "pwm_backlight" and then
> the i915 panel code makes a pwm_get(dev, "pwm_backlight").
>
> Some devices use a PMIC Crystal Cove, but the LCD screen is connected to
> the PWM SoC/LPSS controller (and the VBT indicates it correctly),
> so here the heuristics in drivers/acpi/acpi_lpss.c and
> mfd/intel_soc_pmic_core.c fail.
>
> This series of patches renames the PWM consultations recorded by the
> LPSS / intel_soc_pmic_core.c code from "pwm_backlight" to
> "pwm_soc_backlight" resp. "pwm_pmic_backlight" and, in the case of LPSS,
> also removes the heuristic. This, combined with teaching the
> i915 panel to call pwm_get for the right search name according to the
> bits of the VBT, solves this problem."
>
