Public bug reported: [Impact] The scalar which control the backlight sometimes doesn't respond the first command, so driver can't determinate whether this scalar is in charge of the backlight.
[Fix] Move the retry block not only to read the response, but also includes write command, so that it re-send the command, too. [Test] Verified on the buggy Dell AIO, it passes 30 times and should be more reliable. [Regression Potential] Low, there is no code flow change, just move the retry block to include both write and read command. ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Affects: linux-oem-osp1 (Ubuntu) Importance: Undecided Status: New ** Affects: linux (Ubuntu Bionic) Importance: Undecided Status: New ** Affects: linux-oem-osp1 (Ubuntu Bionic) Importance: Undecided Status: New ** Affects: linux (Ubuntu Eoan) Importance: Undecided Status: New ** Affects: linux (Ubuntu Focal) Importance: Undecided Status: New ** Affects: linux-oem-osp1 (Ubuntu Focal) Importance: Undecided Status: New ** Also affects: linux (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1863880 Title: Another Dell AIO backlight issue Status in linux package in Ubuntu: New Status in linux-oem-osp1 package in Ubuntu: New Status in linux source package in Bionic: New Status in linux-oem-osp1 source package in Bionic: New Status in linux source package in Eoan: New Status in linux source package in Focal: New Status in linux-oem-osp1 source package in Focal: New Bug description: [Impact] The scalar which control the backlight sometimes doesn't respond the first command, so driver can't determinate whether this scalar is in charge of the backlight. [Fix] Move the retry block not only to read the response, but also includes write command, so that it re-send the command, too. [Test] Verified on the buggy Dell AIO, it passes 30 times and should be more reliable. [Regression Potential] Low, there is no code flow change, just move the retry block to include both write and read command. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1863880/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp