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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-16 19:59:10 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-16 19:59:10 -0700
commitad062195731bea1624ce7160e79e0fcdaa25c1b5 (patch)
tree13a8b484abc78118de172195fc87d4d9e38efb80 /Documentation
parent7ac63f6ba5db5e2e81e4674551d6f9ec58e70618 (diff)
parentf690790c9da3122dd7ee1b0d64d97973a7c34135 (diff)
Merge tag 'platform-drivers-x86-v5.4-1' of git://git.infradead.org/linux-platform-drivers-x86
Pull x86 platform-drivers updates from Andy Shevchenko: - ASUS WMI driver got a couple of updates, i.e. support of FAN is fixed for recent products and the charge threshold support has been added - Two uknown key events for Dell laptops are being ignored now to avoid spamming users with harmless messages - HP ZBook 17 G5 and ASUS Zenbook UX430UNR got accelerometer support. - Intel CherryTrail platforms had a regression with wake up. Now it's fixed - Intel PMC driver got fixed in order to work nicely in Xen environment - Intel Speed Select driver provides bucket vs core count relationship. Besides that the tools has been updated for better output - The PrivacyGuard is enabled on Lenovo ThinkPad laptops - Three tablets - Trekstor Primebook C11B 2-in-1, Irbis TW90 and Chuwi Surbook Mini - got touchscreen support * tag 'platform-drivers-x86-v5.4-1' of git://git.infradead.org/linux-platform-drivers-x86: (53 commits) MAINTAINERS: Switch PDx86 subsystem status to Odd Fixes platform/x86: asus-wmi: Refactor charge threshold to use the battery hooking API platform/x86: asus-wmi: Rename CHARGE_THRESHOLD to RSOC platform/x86: asus-wmi: Reorder ASUS_WMI_CHARGE_THRESHOLD tools/power/x86/intel-speed-select: Display core count for bucket platform/x86: ISST: Allow additional TRL MSRs tools/power/x86/intel-speed-select: Fix memory leak tools/power/x86/intel-speed-select: Output success/failed for command output tools/power/x86/intel-speed-select: Output human readable CPU list tools/power/x86/intel-speed-select: Change turbo ratio output to maximum turbo frequency tools/power/x86/intel-speed-select: Switch output to MHz tools/power/x86/intel-speed-select: Simplify output for turbo-freq and base-freq tools/power/x86/intel-speed-select: Fix cpu-count output tools/power/x86/intel-speed-select: Fix help option typo tools/power/x86/intel-speed-select: Fix package typo tools/power/x86/intel-speed-select: Fix a read overflow in isst_set_tdp_level_msr() platform/x86: intel_int0002_vgpio: Use device_init_wakeup platform/x86: intel_int0002_vgpio: Fix wakeups not working on Cherry Trail platform/x86: compal-laptop: Initialize "value" in ec_read_u8() platform/x86: touchscreen_dmi: Add info for the Trekstor Primebook C11B 2-in-1 ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/admin-guide/laptops/thinkpad-acpi.rst23
1 files changed, 23 insertions, 0 deletions
diff --git a/Documentation/admin-guide/laptops/thinkpad-acpi.rst b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
index adea0bf2acc5..822907dcc845 100644
--- a/Documentation/admin-guide/laptops/thinkpad-acpi.rst
+++ b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
@@ -49,6 +49,7 @@ detailed description):
- Fan control and monitoring: fan speed, fan enable/disable
- WAN enable and disable
- UWB enable and disable
+ - LCD Shadow (PrivacyGuard) enable and disable
A compatibility table by model and feature is maintained on the web
site, http://ibm-acpi.sf.net/. I appreciate any success or failure
@@ -1409,6 +1410,28 @@ Sysfs notes
Documentation/driver-api/rfkill.rst for details.
+LCD Shadow control
+------------------
+
+procfs: /proc/acpi/ibm/lcdshadow
+
+Some newer T480s and T490s ThinkPads provide a feature called
+PrivacyGuard. By turning this feature on, the usable vertical and
+horizontal viewing angles of the LCD can be limited (as if some privacy
+screen was applied manually in front of the display).
+
+procfs notes
+^^^^^^^^^^^^
+
+The available commands are::
+
+ echo '0' >/proc/acpi/ibm/lcdshadow
+ echo '1' >/proc/acpi/ibm/lcdshadow
+
+The first command ensures the best viewing angle and the latter one turns
+on the feature, restricting the viewing angles.
+
+
EXPERIMENTAL: UWB
-----------------