> -----Original Message----- > From: Damien Thébault [mailto:damien@xxxxxxxx] > Sent: Tuesday, September 4, 2018 6:46 AM > To: Paul Sarraffe > Cc: pali.rohar@xxxxxxxxx; Limonciello, Mario; platform-driver- > x86@xxxxxxxxxxxxxxx; Darren Hart; Andy Shevchenko > Subject: Re: [psarraf@xxxxxxxxx: [acpi] ACPI brightness control on DELL laptop > Inspiron N4010 not working after update to kernel 4.17.19] > > > Date: Fri, 31 Aug 2018 16:16:20 +0000 (UTC) > > From: Paul Sarraffe <psarraf@xxxxxxxxx> > > To: "fedora-kernel-acpi@xxxxxxxxxxxxxxxxx" > > > > Kernel update 4.17.19 broke the brightness control on my DELL Inspiron > > N4010. It worked fine with kernel 4.17.18. > > > > It appears that the following change fixed brightness control on some > > DELL laptops while breaking it on others: > > commit 587eb87b45bb6a97452b9719f63cd489e1371e77 > > Author: Damien Thébault <damien@xxxxxxxx> > > Date: Wed Jul 18 12:06:01 2018 +0200 > > > > platform/x86: dell-laptop: Fix backlight detection > > > > [ Upstream commit 2502e5a025935b7b476b69eda4959b3c4022c72b ] > > Hello Paul, > > The SMM refactoring change that this commit was intended to fix occured > between 4.14 and 4.15, do you have a way to check those kernel versions > ? > This would allow to verify if it worked before the SMM refactoring. > > I don't know this subject much, but the BIOS might be replying something > not expected in the code. > Are you connected to AC power during boot ? > Maybe utilities from the libsmbios project could allow to investigate > the issue ? > -- > Damien Thébault I agree, please try 4.14 and 4.15 first to see how those work on this model.
