What does the kernel boot parameter "set acpi_osi=Linux" do?
- by AIB
I am facing an issue with brightness control in my laptop which has Intel HD graphics. So when I searched for a fix I found that a common suggestion is to edit the GRUB file line,
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
to
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"
So could anyone tell me what the kernel boot option acpi_osi=Linux do?
My OS is Ubuntu 10.10 64-bit version
update
The boot parameter acpi_osi is used as follows,
acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
acpi_osi="string1" # add string1 -- only one string
acpi_osi="!string2" # remove built-in string2
acpi_osi= # disable all strings
But still I don't find a reason why this should fix any laptop issue!!