Lenovo ThinkPad T480s
| Device | Status |
| Intel graphics | Yes |
| Wireless | Yes |
| ALSA | no beep |
| TrackPoint | Yes |
| Touchpad | Yes |
| Webcam | Yes |
| Fingerprint Reader | No |
| Mobile Broadband | Yes |
| Bluetooth | Yes |
| Smartcard Reader | Yes |
| PrivacyGuard | Yes |
This article covers the installation and configuration of Arch Linux on a Lenovo T480s laptop. For the most part things work out-of-the-box, but there are some features that are unavailable.
For a general overview of laptop-related articles and recommendations, see Laptop.
Contents
Hardware
Using kernel 4.15.7-1-ARCH.
Release Date: 01/22/2018 Product Name: 20L7CTO1WW SKU Number: LENOVO_MT_20L7_BU_Think_FM_ThinkPad T480s Product Name: 20L7CTO1WW
lspci returns something like:
00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v6/7th Gen Core Processor Host Bridge/DRAM Registers (rev 08) 00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 620 (rev 07) 00:04.0 Signal processing controller: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem (rev 08) 00:08.0 System peripheral: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th Gen Core Processor Gaussian Mixture Model 00:14.0 USB controller: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller (rev 21) 00:14.2 Signal processing controller: Intel Corporation Sunrise Point-LP Thermal subsystem (rev 21) 00:15.0 Signal processing controller: Intel Corporation Sunrise Point-LP Serial IO I2C Controller #0 (rev 21) 00:16.0 Communication controller: Intel Corporation Sunrise Point-LP CSME HECI #1 (rev 21) 00:1c.0 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #1 (rev f1) 00:1c.4 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #5 (rev f1) 00:1c.6 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #7 (rev f1) 00:1d.0 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #9 (rev f1) 00:1f.0 ISA bridge: Intel Corporation Device 9d4e (rev 21) 00:1f.2 Memory controller: Intel Corporation Sunrise Point-LP PMC (rev 21) 00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21) 00:1f.4 SMBus: Intel Corporation Sunrise Point-LP SMBus (rev 21) 00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection (4) I219-V (rev 21) 04:00.0 PCI bridge: Intel Corporation JHL6240 Thunderbolt 3 Bridge (Low Power) [Alpine Ridge LP 2016] (rev 01) 05:00.0 PCI bridge: Intel Corporation JHL6240 Thunderbolt 3 Bridge (Low Power) [Alpine Ridge LP 2016] (rev 01) 05:01.0 PCI bridge: Intel Corporation JHL6240 Thunderbolt 3 Bridge (Low Power) [Alpine Ridge LP 2016] (rev 01) 05:02.0 PCI bridge: Intel Corporation JHL6240 Thunderbolt 3 Bridge (Low Power) [Alpine Ridge LP 2016] (rev 01) 06:00.0 System peripheral: Intel Corporation JHL6240 Thunderbolt 3 NHI (Low Power) [Alpine Ridge LP 2016] (rev 01) 3c:00.0 USB controller: Intel Corporation Device 15c1 (rev 01) 3d:00.0 Network controller: Intel Corporation Wireless 8265 / 8275 (rev 78) 3e:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd Device a808
lsusb returns something like:
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 013: ID 0bda:0316 Realtek Semiconductor Corp. Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 004: ID 5986:2113 Acer, Inc Bus 001 Device 003: ID 8087:0a2b Intel Corp. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
lsusb (touchscreen model 20L8) returns something like:
Bus 002 Device 002: ID 0bda:0316 Realtek Semiconductor Corp. USB3.0-CRW Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 004: ID 06cb:009a Synaptics, Inc. Bus 001 Device 003: ID 5986:2113 Acer, Inc Integrated Camera Bus 001 Device 005: ID 04f3:2398 Elan Microelectronics Corp. Touchscreen Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
USB-C DisplayPort
The following adapters were tested:
- Dell DA300
- Ethernet/HDMI/USB-A/DisplayPort all work. Display output maxes out at 2560x1440@60Hz / 3840x2160@30Hz. 4k@60Hz wasn't possible even with a modeline generated with cvt.
- Moshi USB-C to HDMI Adapter
- Up to 4k@60Hz Works out of the box with xrandr.
- Ugreen USB-C Hub for Macbook
- Everything works out of the box (3840x2160@60Hz not tested), most probably all of the variations of this hub work too.
Powersaving
Without special configuration and with default firmware settings, power usage is a bit high (around 7,5W in idle). There are a few knobs to improve battery life:
- Set "Thunderbolt BIOS Assist Mode" to "Enabled" in the EFI firmware interface. This seems to reduce number of idle wakeups.
- Disable unused peripherals under "Security" -> "I/O port access" in the firmware. This especially applies to the SD/MMC-cardreader, which seems to drain some power even when idle
As of Kernel 4.15, DisplayPort PSR (Panel self refresh) is disabled by default and broken when forcibly enabled (system hangs after a few seconds, display lag). 4.17-rc1 seems to improve a lot in this regard, but PSR still sometimes causes the screen to freeze for a few seconds.
SD Card Reader
According to various reports the SD card reader drains several watts of power. If you don't want to disable it in bios because you use it semi-regularly, you can turn it off by unbinding its driver using this command:
echo "2-3" | sudo tee /sys/bus/usb/drivers/usb/unbind
You can then turn the reader back on by running:
echo "2-3" | sudo tee /sys/bus/usb/drivers/usb/bind
Known Issues
Fingerprint Reader
The fingerprint sensor 06cb:009a is not supported by libfprint. There is a project to reverse enginer the Windows driver.[6]
Troubleshooting
Thermal Throttling
There are reported throttling issues for Lenovo T480/T480s/X1C6 notebooks.[7]
This script forces the CPU package power limit (PL1/2) to 44 W (29 W on battery) and the temperature trip point to 95 'C (85 'C on battery) by overriding default values in MSR and MCHBAR every 5 seconds (30 on battery) to block the Embedded Controller from resetting these values to default.
Install the throttled package and enable the lenovo_fix.service.[8]
It is recommended to also undervolt the CPU (Undervolting CPU#intel-undervolt). Most Kaby Lake R chips are able to easily undervolt to -100mV or more, which significantly helps to keep the device from thermal throttling.
PrivacyGuard
The PrivacyGuard feature is referred to as LCD Shadow [9] and was introduced in Linux 5.4.[10]
To enable or turn on the LCD shadow:
echo 1 | sudo tee /proc/acpi/ibm/lcdshadow
Conversely, use 0 to disable it:
echo 0 | sudo tee /proc/acpi/ibm/lcdshadow
Fix freezes/hangs on QT applications (with Intel driver)
See Intel graphics#AccelMethod.