Samsung Galaxy Tab S 10.5 WiFi (samsung-chagallwifi)

Contributors

 * dwrdj
 * grimler

How to enter flash mode
Press and hold +  +. Press when prompted

Installation
To install postmarketOS to an sdcard, insert the sdcard to your computer, check the /dev mountpoint with for example fdisk, and run

where sdX should be replaced by the mountpoint. After that flash the kernel with

and the tablet should automatically reboot into postmarketOS.

To install postmarketOS to the internal storage the easiest way is to create a zip to flash from twrp, run

And then copy or  /tmp/postmarketOS-export/pmos-samsung-chagallwifi.zip to your device, reboot to twrp and install the zip and then reboot to system.

Alternatively you can flash the kernel with heimdall from download mode and then install the rootfs with netcat by running:

You can now telnet to the device and netcat the postmarketOS installation:

Open another console

Wifi in downstream kernel
To connect to a wifi the same steps as for the Medion Lifetab S9714 (medion-kai) work:

1. Verify that the wlan0 interface exists

2. Turn on wifi

3. List available wifis

4. Connect to your wifi

5. Verify that you have been given an ip address on the wlan0, or swlan0, interface

Issues in downstream (apart from broken components)
Touchscreen does not work fully after a while (after device sleeps?). Cursor still moves, but it is impossible to click, or double click, things. This has been observed in xfce, happens on klimtlte as well.

Mainline kernel status
A work in progress mainline kernel (linux-postmarketos-exynos5) is available (can be chosen in pmbootstrap init step). You can install postmarketOS to either the internal or external storage and ssh into the tablet over USB. Display, wifi and everything else are not working.

Command Line and serial output
when running LineageOS 15.1 contains:

console=ram loglevel=4 sec_debug.level=0 sec_watchdog.sec_pet=5 androidboot.debug_level=0x4f4c sec_log=0x200000@0x26000000 sec_tima_log=0x200000@0x26202000 sec_avc_log=0x40000@0x26404000 s3cfb.bootloaderfb=0x67000000 lcdtype=5410823 consoleblank=0 lpj=3977216 vmalloc=512m sec_debug.reset_reason=7 oops=panic pmic_info=67 cordon=e2693b1e8c8724879b6f74b29a0120f3 connie=SM-T800_OPEN_EUR_c7e33ee79c0aa018334d7f72d27d952a androidboot.emmc_checksum=3 androidboot.boot_salescode= androidboot.odin_download=1 androidboot.bootloader=T800XXU1BOJ1 androidboot.selinux=enforcing androidboot.hardware=universal5420 androidboot.warranty_bit=1 androidboot.sec_atd.tty=/dev/ttySAC2 androidboot.serialno=[removed] snd_soc_core.pmdown_time=1000

Simply attaching a serial debugging cable (use a 619 kOhm resistor) gives output from the bootloader, but not from the kernel. The reason for this is that  is passed on the cmdline from the bootloader. We need to override this to specify. This is already part of the default cmdline in the kernel config, but this is then ignored due to CONFIG_CMDLINE_FROM_BOOTLOADER=y being set. To instead concatenate the cmdline from the config to the bootloader cmdline, unset CONFIG_CMDLINE_FROM_BOOTLOADER and set CONFIG_CMDLINE_EXTEND=y, i.e. apply:

If there is no traffic when booting after you plug in the cable you might also need to restart/reset the device (hold vol down + home + power) to get it going.