Reboot/shutdown ACPI PTS issue
Dell Latitude E5*50 Linux support
Tested on a Dell Latitude E5450 (late 2014) with Fedora 22/23 64bit, BIOS A10-A12.
Please note: BIOS prior to A06 have a serious issue with de-bouncing/repeating keys under Linux, see http://en.community.dell.com/support-forums/laptop/f/3518/t/19593360. Updating to A10 or higher is strongly reccomended.
Shutdown/reboot issues with kernel >= 4.8
See kernel/README.md
WWAN module
Dell Latitude E5*50 laptops could have a "Dell Wireless 5809e Gobi™ 4G LTE Mobile Broadband Card" WWAN module installed. This WWAN device is based on the Qualcomm Gobi™.
| Name | Dell Wireless 5809e Gobi™ 4G LTE Mobile Broadband Card | 
| ID | 413c:81b1 | 
| Kernel module | qcserial, qmi_wwan | 
The device id of this Gobi™ module is still missing from the qcserial devices table, so I created a udev rule which loads the qcserial module, switchs the bConfigurationValue from 2 to 1** and adds the new device id 413c:81b1 to the qcserial driver. Current version of the udev rule loads the qmi_wwan modules too and adds the device id to that module to allow 4G/LTE connection through modern versions of NetworkManager/ModemManager.
** By default the device is loaded in the cdc_mbim mode (see https://www.kernel.org/doc/Documentation/networking/cdc_mbim.txt) instead in the classic serial modem mode.
GPS
To start the GPS
echo "\$GPS_START" > /dev/ttyUSB0
To stop the GPS
echo "\$GPS_STOP" > /dev/ttyUSB0
In the bin folder you can find an utility (gobigps) to easily start and stop the GPS. To be able to use this utility as normal user (more in general, to use the GPS) the user must be member of the dialout group.
You can check if the GPS is running with a simple cat
cat /dev/ttyUSB0
or using QGIS.
Smart-card reader (Fedora <= 22 only)
NOTE: this is not needed anymore, starting from Fedora 23, since pcsc-lite-ccid-1.4.19 is now part of the stable release.
The Broadcom 5880v5 used in this Latitude (id 0a5c:5804) is supported by pcsc-lite-ccid starting from release 1.4.19. Fedora 21 and 22 provide version 1.4.18; pcsc-lite-ccid-1.4.19, backported from rawhide, can be downloaded from the following repo:
https://copr.fedoraproject.org/coprs/dani/ccid-drivers-backport/
Using DNF:
sudo dnf copr enable dani/ccid-drivers-backport
sudo dnf install pcsc-lite-ccid
Using YUM:
wget -O- https://copr.fedoraproject.org/coprs/dani/ccid-drivers-backport/repo/fedora-21/dani-ccid-drivers-backport-fedora-21.repo | sudo tee /etc/yum.repos.d/dani-ccid-drivers-backport-fedora-21.repo
sudo yum install pcsc-lite-ccid