From 078ac19ed8f476a7c2d729712e15f5ab516ff491 Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:44 +0000 Subject: thinkpad-acpi: documentation cleanup Some cleanups to the documentation of the driver. Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 76 ++++++++++++++++++++++----------- 1 file changed, 52 insertions(+), 24 deletions(-) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index 41bc99fa188..f6e6bc66eed 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -20,7 +20,8 @@ moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel kernel 2.6.29 and release 0.22. The driver is named "thinkpad-acpi". In some places, like module -names, "thinkpad_acpi" is used because of userspace issues. +names and log messages, "thinkpad_acpi" is used because of userspace +issues. "tpacpi" is used as a shorthand where "thinkpad-acpi" would be too long due to length limitations on some Linux kernel versions. @@ -37,7 +38,7 @@ detailed description): - ThinkLight on and off - limited docking and undocking - UltraBay eject - - CMOS control + - CMOS/UCMS control - LED control - ACPI sounds - temperature sensors @@ -46,6 +47,7 @@ detailed description): - Volume control - Fan control and monitoring: fan speed, fan enable/disable - WAN enable and disable + - UWB 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 @@ -53,7 +55,7 @@ reports, especially if they add to or correct the compatibility table. Please include the following information in your report: - ThinkPad model name - - a copy of your DSDT, from /proc/acpi/dsdt + - a copy of your ACPI tables, using the "acpidump" utility - a copy of the output of dmidecode, with serial numbers and UUIDs masked off - which driver features work and which don't @@ -66,17 +68,18 @@ Installation ------------ If you are compiling this driver as included in the Linux kernel -sources, simply enable the CONFIG_THINKPAD_ACPI option, and optionally -enable the CONFIG_THINKPAD_ACPI_BAY option if you want the -thinkpad-specific bay functionality. +sources, look for the CONFIG_THINKPAD_ACPI Kconfig option. +It is located on the menu path: "Device Drivers" -> "X86 Platform +Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras". + Features -------- The driver exports two different interfaces to userspace, which can be used to access the features it provides. One is a legacy procfs-based -interface, which will be removed at some time in the distant future. -The other is a new sysfs-based interface which is not complete yet. +interface, which will be removed at some time in the future. The other +is a new sysfs-based interface which is not complete yet. The procfs interface creates the /proc/acpi/ibm directory. There is a file under that directory for each feature it supports. The procfs @@ -111,15 +114,17 @@ The version of thinkpad-acpi's sysfs interface is exported by the driver as a driver attribute (see below). Sysfs driver attributes are on the driver's sysfs attribute space, -for 2.6.23 this is /sys/bus/platform/drivers/thinkpad_acpi/ and +for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and /sys/bus/platform/drivers/thinkpad_hwmon/ Sysfs device attributes are on the thinkpad_acpi device sysfs attribute -space, for 2.6.23 this is /sys/devices/platform/thinkpad_acpi/. +space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/. Sysfs device attributes for the sensors and fan are on the thinkpad_hwmon device's sysfs attribute space, but you should locate it -looking for a hwmon device with the name attribute of "thinkpad". +looking for a hwmon device with the name attribute of "thinkpad", or +better yet, through libsensors. + Driver version -------------- @@ -129,6 +134,7 @@ sysfs driver attribute: version The driver name and version. No commands can be written to this file. + Sysfs interface version ----------------------- @@ -160,6 +166,7 @@ expect that an attribute might not be there, and deal with it properly (an attribute not being there *is* a valid way to make it clear that a feature is not available in sysfs). + Hot keys -------- @@ -618,6 +625,7 @@ For Lenovo models *with* ACPI backlight control: and map them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN. Process these keys on userspace somehow (e.g. by calling xbacklight). + Bluetooth --------- @@ -628,6 +636,9 @@ sysfs rfkill class: switch "tpacpi_bluetooth_sw" This feature shows the presence and current state of a ThinkPad Bluetooth device in the internal ThinkPad CDC slot. +If the ThinkPad supports it, the Bluetooth state is stored in NVRAM, +so it is kept across reboots and power-off. + Procfs notes: If Bluetooth is installed, the following commands can be used: @@ -652,6 +663,7 @@ Sysfs notes: rfkill controller switch "tpacpi_bluetooth_sw": refer to Documentation/rfkill.txt for details. + Video output control -- /proc/acpi/ibm/video -------------------------------------------- @@ -693,11 +705,8 @@ Fn-F7 from working. This also disables the video output switching features of this driver, as it uses the same ACPI methods as Fn-F7. Video switching on the console should still work. -UPDATE: There's now a patch for the X.org Radeon driver which -addresses this issue. Some people are reporting success with the patch -while others are still having problems. For more information: +UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000 -https://bugs.freedesktop.org/show_bug.cgi?id=2000 ThinkLight control ------------------ @@ -720,10 +729,11 @@ The ThinkLight sysfs interface is documented by the LED class documentation, in Documentation/leds-class.txt. The ThinkLight LED name is "tpacpi::thinklight". -Due to limitations in the sysfs LED class, if the status of the thinklight +Due to limitations in the sysfs LED class, if the status of the ThinkLight cannot be read or if it is unknown, thinkpad-acpi will report it as "off". It is impossible to know if the status returned through sysfs is valid. + Docking / undocking -- /proc/acpi/ibm/dock ------------------------------------------ @@ -784,6 +794,7 @@ the only docking stations currently supported are the X-series UltraBase docks and "dumb" port replicators like the Mini Dock (the latter don't need any ACPI support, actually). + UltraBay eject -- /proc/acpi/ibm/bay ------------------------------------ @@ -847,8 +858,9 @@ supported. Use "eject2" instead of "eject" for the second bay. Note: the UltraBay eject support on the 600e/x, A22p and A3x is EXPERIMENTAL and may not work as expected. USE WITH CAUTION! -CMOS control ------------- + +CMOS/UCMS control +----------------- procfs: /proc/acpi/ibm/cmos sysfs device attribute: cmos_command @@ -882,6 +894,7 @@ The cmos command interface is prone to firmware split-brain problems, as in newer ThinkPads it is just a compatibility layer. Do not use it, it is exported just as a debug tool. + LED control ----------- @@ -939,6 +952,7 @@ ThinkPad indicator LED should blink in hardware accelerated mode, use the "timer" trigger, and leave the delay_on and delay_off parameters set to zero (to request hardware acceleration autodetection). + ACPI sounds -- /proc/acpi/ibm/beep ---------------------------------- @@ -968,6 +982,7 @@ X40: 16 - one medium-pitched beep repeating constantly, stop with 17 17 - stop 16 + Temperature sensors ------------------- @@ -1115,6 +1130,7 @@ registers contain the current battery capacity, etc. If you experiment with this, do send me your results (including some complete dumps with a description of the conditions when they were taken.) + LCD brightness control ---------------------- @@ -1124,10 +1140,9 @@ sysfs backlight device "thinkpad_screen" This feature allows software control of the LCD brightness on ThinkPad models which don't have a hardware brightness slider. -It has some limitations: the LCD backlight cannot be actually turned on or -off by this interface, and in many ThinkPad models, the "dim while on -battery" functionality will be enabled by the BIOS when this interface is -used, and cannot be controlled. +It has some limitations: the LCD backlight cannot be actually turned +on or off by this interface, it just controls the backlight brightness +level. On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control has eight brightness levels, ranging from 0 to 7. Some of the levels @@ -1201,6 +1216,7 @@ WARNING: and maybe reduce the life of the backlight lamps by needlessly kicking its level up and down at every change. + Volume control -- /proc/acpi/ibm/volume --------------------------------------- @@ -1217,6 +1233,11 @@ distinct. The unmute the volume after the mute command, use either the up or down command (the level command will not unmute the volume). The current volume level and mute state is shown in the file. +The ALSA mixer interface to this feature is still missing, but patches +to add it exist. That problem should be addressed in the not so +distant future. + + Fan control and monitoring: fan speed, fan enable/disable --------------------------------------------------------- @@ -1383,8 +1404,11 @@ procfs: /proc/acpi/ibm/wan sysfs device attribute: wwan_enable (deprecated) sysfs rfkill class: switch "tpacpi_wwan_sw" -This feature shows the presence and current state of a W-WAN (Sierra -Wireless EV-DO) device. +This feature shows the presence and current state of the built-in +Wireless WAN device. + +If the ThinkPad supports it, the WWAN state is stored in NVRAM, +so it is kept across reboots and power-off. It was tested on a Lenovo ThinkPad X60. It should probably work on other ThinkPad models which come with this module installed. @@ -1413,6 +1437,7 @@ Sysfs notes: rfkill controller switch "tpacpi_wwan_sw": refer to Documentation/rfkill.txt for details. + EXPERIMENTAL: UWB ----------------- @@ -1431,6 +1456,7 @@ Sysfs notes: rfkill controller switch "tpacpi_uwb_sw": refer to Documentation/rfkill.txt for details. + Multiple Commands, Module Parameters ------------------------------------ @@ -1445,6 +1471,7 @@ for example: modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable + Enabling debugging output ------------------------- @@ -1467,6 +1494,7 @@ The level of debugging information output by the driver can be changed at runtime through sysfs, using the driver attribute debug_level. The attribute takes the same bitmask as the debug module parameter above. + Force loading of module ----------------------- -- cgit v1.2.3 From 73a94d86a8625371f76de0ee12dc5bacd3ed42c0 Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:47 +0000 Subject: thinkpad-acpi: add new debug helpers and warn of deprecated atts Add a debug helper that discloses the TGID of the userspace task attempting to access the driver. This is highly useful when dealing with bug reports, since often the user has no idea that some userspace application is accessing thinkpad-acpi... Also add a helper to log warnings about sysfs attributes that are deprecated. Use the new helpers to issue deprecation warnings for bluetooth_enable and wwan_enabled, that have been deprecated for a while, now. Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index f6e6bc66eed..e8f52fbadfe 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1484,6 +1484,8 @@ will enable all debugging output classes. It takes a bitmask, so to enable more than one output class, just add their values. Debug bitmask Description + 0x8000 Disclose PID of userspace programs + accessing some functions of the driver 0x0001 Initialization and probing 0x0002 Removal -- cgit v1.2.3 From 2586d5663d0a17d69383acf6110f16a979a07c4e Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:48 +0000 Subject: thinkpad-acpi: remove HKEY disable functionality The HKEY disable functionality basically cripples the entire event model of the ThinkPad firmware and of the thinkpad-acpi driver. Remove this functionality from the driver. HKEY must be enabled at all times while thinkpad-acpi is loaded, and disabled otherwise. For sysfs, according to the sysfs ABI and the thinkpad-acpi sysfs rules of engagement, we will just remove the attributes. This will be done in two stages: disable their function now, after two kernel releases, remove the attributes. For procfs, we call WARN(). If nothing triggers it, I will simply remove the enable/disable commands entirely in the future along with the sysfs attributes. I don't expect much, if any fallout from this. There really isn't any reason to mess with hotkey_enable or with the enable/disable commands to /proc/acpi/ibm/hotkey, and this has been true for years... Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 39 ++++++++++++++++----------------- 1 file changed, 19 insertions(+), 20 deletions(-) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index e8f52fbadfe..de6f14c7907 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -179,17 +179,14 @@ system. Enabling the hotkey functionality of thinkpad-acpi signals the firmware that such a driver is present, and modifies how the ThinkPad firmware will behave in many situations. -The driver enables the hot key feature automatically when loaded. The -feature can later be disabled and enabled back at runtime. The driver -will also restore the hot key feature to its previous state and mask -when it is unloaded. +The driver enables the HKEY ("hot key") event reporting automatically +when loaded, and disables it when it is removed. -When the hotkey feature is enabled and the hot key mask is set (see -below), the driver will report HKEY events in the following format: +The driver will report HKEY events in the following format: ibm/hotkey HKEY 00000080 0000xxxx -Some of these events refer to hot key presses, but not all. +Some of these events refer to hot key presses, but not all of them. The driver will generate events over the input layer for hot keys and radio switches, and over the ACPI netlink layer for other events. The @@ -221,13 +218,17 @@ procfs notes: The following commands can be written to the /proc/acpi/ibm/hotkey file: - echo enable > /proc/acpi/ibm/hotkey -- enable the hot keys feature - echo disable > /proc/acpi/ibm/hotkey -- disable the hot keys feature echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys ... any other 8-hex-digit mask ... echo reset > /proc/acpi/ibm/hotkey -- restore the original mask +The following commands have been deprecated and will cause the kernel +to log a warning: + + echo enable > /proc/acpi/ibm/hotkey -- does nothing + echo disable > /proc/acpi/ibm/hotkey -- returns an error + The procfs interface does not support NVRAM polling control. So as to maintain maximum bug-to-bug compatibility, it does not report any masks, nor does it allow one to manipulate the hot key mask when the firmware @@ -236,12 +237,9 @@ does not support masks at all, even if NVRAM polling is in use. sysfs notes: hotkey_bios_enabled: - Returns the status of the hot keys feature when - thinkpad-acpi was loaded. Upon module unload, the hot - key feature status will be restored to this value. + DEPRECATED, WILL BE REMOVED SOON. - 0: hot keys were disabled - 1: hot keys were enabled (unusual) + Returns 0. hotkey_bios_mask: Returns the hot keys mask when thinkpad-acpi was loaded. @@ -249,13 +247,10 @@ sysfs notes: to this value. hotkey_enable: - Enables/disables the hot keys feature in the ACPI - firmware, and reports current status of the hot keys - feature. Has no effect on the NVRAM hot key polling - functionality. + DEPRECATED, WILL BE REMOVED SOON. - 0: disables the hot keys feature / feature disabled - 1: enables the hot keys feature / feature enabled + 0: returns -EPERM + 1: does nothing hotkey_mask: bit mask to enable driver-handling (and depending on @@ -1535,3 +1530,7 @@ Sysfs interface changelog: 0x020200: Add poll()/select() support to the following attributes: hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason + +0x020300: hotkey enable/disable support removed, attributes + hotkey_bios_enabled and hotkey_enable deprecated and + marked for removal. -- cgit v1.2.3 From a4d5effcc73749ee3ebbf578d162905e6fa4e07d Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:49 +0000 Subject: thinkpad-acpi: restrict access to some firmware LEDs Some of the ThinkPad LEDs indicate critical conditions that can cause data loss or cause hardware damage when ignored (e.g. force-ejecting a powered up bay; ignoring a failing battery, or empty battery; force- undocking with the dock buses still active, etc). On almost all ThinkPads, LED access is write-only, and the firmware usually does fire-and-forget signaling on them, so you effectively lose whatever message the firmware was trying to convey to the user when you override the LED state, without any chance to restore it. Restrict access to all LEDs that can convey important alarms, or that could mislead the user into incorrectly operating the hardware. This will make the Lenovo engineers less unhappy about the whole issue. Allow users that really want it to still control all LEDs, it is the unaware user that we have to worry about. Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index de6f14c7907..bce1d959b70 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -901,6 +901,17 @@ some older ThinkPad models, it is possible to query the status of the LED indicators as well. Newer ThinkPads cannot query the real status of the LED indicators. +Because misuse of the LEDs could induce an unaware user to perform +dangerous actions (like undocking or ejecting a bay device while the +buses are still active), or mask an important alarm (such as a nearly +empty battery, or a broken battery), access to most LEDs is +restricted. + +Unrestricted access to all LEDs requires that thinkpad-acpi be +compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled. +Distributions must never enable this option. Individual users that +are aware of the consequences are welcome to enabling it. + procfs notes: The available commands are: -- cgit v1.2.3 From bee4cd9b9eaa8c72832e1ee7f4940604e94beb27 Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:50 +0000 Subject: thinkpad-acpi: enhanced debugging messages for rfkill subdrivers Enhance debugging messages for all rfkill subdrivers in thinkpad-acpi. Also, log a warning if the deprecated sysfs attributes are in use. These attributes are going to be removed sometime in 2010. There is an user-visible side-effect: we now coalesce attempts to enable/disable bluetooth or WWAN in the procfs interface, instead of hammering the firmware with multiple requests. Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index bce1d959b70..7daca055367 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1494,6 +1494,8 @@ to enable more than one output class, just add their values. accessing some functions of the driver 0x0001 Initialization and probing 0x0002 Removal + 0x0004 RF Transmitter control (RFKILL) + (bluetooth, WWAN, UWB...) There is also a kernel build option to enable more debugging information, which may be necessary to debug driver problems. -- cgit v1.2.3 From 56e2c200945dafafb86169762eb1e88aed0ce69e Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:51 +0000 Subject: thinkpad-acpi: enhanced debugging messages for the hotkey subdriver Enhance debugging messages for the hotkey subdriver. Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index 7daca055367..abbbe78a003 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1496,6 +1496,7 @@ to enable more than one output class, just add their values. 0x0002 Removal 0x0004 RF Transmitter control (RFKILL) (bluetooth, WWAN, UWB...) + 0x0008 HKEY event interface, hotkeys There is also a kernel build option to enable more debugging information, which may be necessary to debug driver problems. -- cgit v1.2.3 From 74a60c0f828016456fc635feae388ffd12bb3bb9 Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:52 +0000 Subject: thinkpad-acpi: enhanced debugging messages for the fan subdriver Enhance debugging messages for the fan subdriver. Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index abbbe78a003..25ed43d0a21 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1497,6 +1497,7 @@ to enable more than one output class, just add their values. 0x0004 RF Transmitter control (RFKILL) (bluetooth, WWAN, UWB...) 0x0008 HKEY event interface, hotkeys + 0x0010 Fan control There is also a kernel build option to enable more debugging information, which may be necessary to debug driver problems. -- cgit v1.2.3 From 0e501834f8c2ba7de2a56e332d346dcf4ac0b593 Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 4 Apr 2009 04:25:53 +0000 Subject: thinkpad-acpi: rework brightness support Refactor and redesign the brightness control backend... In order to fix bugzilla #11750... Add a new brightness control mode: support direct NVRAM checkpointing of the backlight level (i.e. store directly to NVRAM without the need for UCMS calls), and use that together with the EC-based control. Disallow UCMS+EC, thus avoiding races with the SMM firmware. Switch the models that define HBRV (EC Brightness Value) in the DSDT to the new mode. These are: T40-T43, R50-R52, R50e, R51e, X31-X41. Change the default for all other IBM ThinkPads to UCMS-only. The Lenovo models already default to UCMS-only. Reported-by: Alexey Fisher Signed-off-by: Henrique de Moraes Holschuh Signed-off-by: Len Brown --- Documentation/laptops/thinkpad-acpi.txt | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'Documentation/laptops') diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index 25ed43d0a21..3d7650768bb 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1157,10 +1157,15 @@ display backlight brightness control methods have 16 levels, ranging from 0 to 15. There are two interfaces to the firmware for direct brightness control, -EC and CMOS. To select which one should be used, use the +EC and UCMS (or CMOS). To select which one should be used, use the brightness_mode module parameter: brightness_mode=1 selects EC mode, -brightness_mode=2 selects CMOS mode, brightness_mode=3 selects both EC -and CMOS. The driver tries to auto-detect which interface to use. +brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC +mode with NVRAM backing (so that brightness changes are remembered +across shutdown/reboot). + +The driver tries to select which interface to use from a table of +defaults for each ThinkPad model. If it makes a wrong choice, please +report this as a bug, so that we can fix it. When display backlight brightness controls are available through the standard ACPI interface, it is best to use it instead of this direct @@ -1498,6 +1503,7 @@ to enable more than one output class, just add their values. (bluetooth, WWAN, UWB...) 0x0008 HKEY event interface, hotkeys 0x0010 Fan control + 0x0020 Backlight brightness There is also a kernel build option to enable more debugging information, which may be necessary to debug driver problems. -- cgit v1.2.3