Commit Graph

3 Commits

Author SHA1 Message Date
Lv Zheng f369fdf4f6 Revert "ACPI / button: Remove lid_init_state=method mode"
This reverts commit ecb10b694b.

The only expected ACPI control method lid device's usage model is

 1. Listen to the lid notification,
 2. Evaluate _LID after being notified by BIOS,
 3. Suspend the system (if users configure to do so) after seeing "close".

It's not ensured that BIOS will notify OS after boot/resume, and
it's not ensured that BIOS will always generate "open" event upon
opening the lid.

But there are 2 wrong usage models:

 1. When the lid device is responsible for suspend/resume the system,
    userspace requires to see "open" event to be paired with "close" after
    the system is resumed, or it will suspend the system again.

 2. When an external monitor connects to the laptop attached docks,
    userspace requires to see "close" event after the system is resumed so
    that it can determine whether the internal display should remain dark
    and the external display should be lit on.

After we made default kernel behavior to be suitable for usage model 1,
users of usage model 2 start to report regressions for such behavior
change.

Reversion of button.lid_init_state=method doesn't actually reverts to old
default behavior as doing so can enter a regression loop, but facilitates
users to work the reported regressions around with
button.lid_init_state=method.

Fixes: ecb10b694b (ACPI / button: Remove lid_init_state=method mode)
Cc: 4.11+ <stable@vger.kernel.org> # 4.11+
Link: https://bugzilla.kernel.org/show_bug.cgi?id=195455
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1430259
Tested-by: Steffen Weber <steffen.weber@gmail.com>
Tested-by: Julian Wiedmann <julian.wiedmann@jwi.name>
Reported-by: Joachim Frieben <jfrieben@hotmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-05-12 23:14:59 +02:00
Lv Zheng ecb10b694b ACPI / button: Remove lid_init_state=method mode
The mode is buggy, and lid_init__state=open is more useful than this
mode, so this patch makes it deprecated.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-31 17:20:45 +01:00
Lv Zheng f9151fcfcd ACPI / button: Add document for ACPI control method lid device restrictions
This patch adds documentation for the usage model of the control method lid
device on some buggy platforms.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 01:06:20 +02:00