tmakin/tegra-linux-noble
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

UBUNTU: SAUCE: (no-up) ACPI: Disable Windows 8 compatibility for some Lenovo ThinkPads

Browse Source 
The AML implementation for brightness control on several ThinkPads
contains a workaround to meet a Windows 8 requirement of 101 brightness
levels [1]. The implementation is flawed, as only 16 of the brighness
values reported by _BCL affect a change in brightness. _BCM silently
discards the rest of the values. Disabling Windows 8 compatibility on
these machines reverts them to the old behavior, making _BCL only report
the 16 brightness levels which actually work. Add a quirk to do this
along with a dmi callback to disable Win8 compatibility.

[1] http://msdn.microsoft.com/en-us/library/windows/hardware/jj128256.aspx

BugLink: http://bugs.launchpad.net/bugs/1183856
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
This commit is contained in:
Seth Forshee
2013-09-20 13:03:41 -05:00
committed by Paolo Pisati
parent f97c0196ce
commit e5ed567617
1 changed files with 71 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/acpi/osi.c
+71
View File
@@ -443,6 +443,77 @@ static const struct dmi_system_id acpi_osi_dmi_table[] __initconst = {
},
},
/*
* The following Lenovo models have a broken workaround in the
* acpi_video backlight implementation to meet the Windows 8
* requirement of 101 backlight levels. Reverting to pre-Win8
* behavior fixes the problem.
*/
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad L430",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad L430"),
},
},
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad T430",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T430"),
},
},
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad T430s",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T430s"),
},
},
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad T530",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T530"),
},
},
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad W530",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad W530"),
},
},
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad X1 Carbon",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X1 Carbon"),
},
},
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad X230",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X230"),
},
},
{
.callback = dmi_disable_osi_win8,
.ident = "Lenovo ThinkPad Edge E330",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad Edge E330"),
},
},
/*
* BIOS invocation of _OSI(Linux) is almost always a BIOS bug.
* Linux ignores it, except for the machines enumerated below.