Samsung Galaxy Tab S5e Wi-Fi (gts4lvwifi)

This is the Device page for the "Samsung Galaxy Tab S5e Wi-Fi" (model SM-T720; codename gts4lvwifi), which should not be confused with the similarly-named "Samsung Galaxy Tab S5e LTE" (models SM-T725, SM-T727; codename gts4lv).

Contributors

 * Mparker17

How to enter flash mode
(note that Samsung calls this "Download mode")


 * 1) Power off the device
 * 2) Plug in the device.
 * 3) Hold  +  +  until the screen turns blue.
 * 4) Follow the instructions on screen (it will probably tell you to press  to continue, i.e.: to flash mode)

You will need to use something like Odin, Heimdall, etc. to flash postmarketOS. See Manual flashing for more.

Installation
As of 2021-03-18,  does not work, as Heimdall v1.4.2 does not know how to talk to the device (it returns  ). On 2021-06-29, the patch to Heimdall at https://github.com/Benjamin-Dobell/Heimdall/pull/478 fixes the connection issue.

Odin 3.13.1 can successfully install Samsung's default firmware, TWRP, and LineageOS; but installing PostmarketOS with Odin (i.e.: after exporting the files with ) has not yet been attempted as of 2021-06-29.

Build notes
Overall, Mparker17 found this pretty straightforward using the Porting to a new device instructions.

For a host machine, Mparker17 used Ubuntu 20.10.

For, Mparker17 used:

Channel [edge]: edge Vendor [samsung]: samsung Device codename [gts4lvwifi]: gts4lvwifi Username [user]: user User interface [weston]: weston Additional options: extra free space: 0 MB, boot partition size: 128 MB, parallel jobs: 9, ccache per arch: 5G, sudo timer: False Change them? (y/n) [n]: n Extra packages [none]: none Choose default locale for installation (y/n) [C.UTF-8]: C.UTF-8 Device hostname (short form, e.g. 'foo') [samsung-gts4lvwifi]: samsung-gts4lvwifi Would you like to copy your SSH public keys to the device? (y/n) [n]: n Build outdated packages during 'pmbootstrap install'? (y/n) [y]: y

... and the  from LineageOS' build for the device (specifically, lineage-17.1-20210222-nightly-gts4lvwifi-signed.zip)

When editing, Mparker17 didn't have to add any patches; but did have to remove the following 4 patches:

gcc7-give-up-on-ilog2-const-optimizations.patch gcc8-fix-put-user.patch gcc10-extern_YYLOC_global_declaration.patch kernel-use-the-gnu89-standard-explicitly.patch

For, Mparker17 had to fix the following issues documented on the kconfig page:

WARNING: linux-samsung-gts4lvwifi/config-samsung-gts4lvwifi.aarch64: CONFIG_ANDROID_PARANOID_NETWORK should *not* be set. See  for details. WARNING: linux-samsung-gts4lvwifi/config-samsung-gts4lvwifi.aarch64: CONFIG_DEVTMPFS should be set. See  for details. WARNING: linux-samsung-gts4lvwifi/config-samsung-gts4lvwifi.aarch64: CONFIG_SYSVIPC should be set. See  for details. WARNING: linux-samsung-gts4lvwifi/config-samsung-gts4lvwifi.aarch64: CONFIG_VT should be set. See  for details.

... after fixing those, the kernel appeared to build successfully.

Mparker17 has not had a chance to try this out on the device yet.

Device notes
Some of the gts4lvwifi devices originally shipped with Android 9. LineageOS worked on those devices until sometime in 2020-Q4; after that LineageOS stopped upgrading. The solution for this was to install Samsung's stock firmware for Android 10, and re-flash LineageOS - after that it continued working. Mparker17 recalls this had something to do with Android 10 device drivers, and speculates it might have something to do with LineageOS's kernel fork or device configuration (which we use, see above), and therefore, similar issues might happen with postmarketOS as well. However, Mparker17 doesn't know how to restore the original Android 9 firmware to verify this. So Mparker17's advice is, make sure you've upgraded to the latest official Android 10 firmware before trying to install PostmarketOS.