Samsung Galaxy Tab 3 8.0 (samsung-lt01)

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Samsung Galaxy Tab 3 8.0
Photo of the Galaxy Tab 3 8.0 running postmarketOS
Photo of the Galaxy Tab 3 8.0 running postmarketOS
Manufacturer Samsung
Name Galaxy Tab 3 8.0
Codename samsung-lt01
Model SM-T310, SM-T311, SM-T315
Released 2013
Category testing
Pre-built images no
Original software Android
Original version 4.2.2
postmarketOS kernel 6.7.6
Hardware
Chipset Samsung Exynos 4212 Dual
CPU Dual-core 1.5 GHz Cortex-A9
GPU Mali-400MP4
Display 800x1280
Storage 16GB
Memory 1.5GB
Architecture ARMv7
Type tablet
Features
USB Networking
Works
Flashing
Works
Touchscreen
Works
Display
Works
WiFi
Works
FDE
Mainline
Works
Battery
Partial
3D Acceleration
Works
Audio
Partial
Bluetooth
Works
Camera
Broken
GPS
Broken
Internal storage
Works
USB OTG
Broken
Sensors
Accelerometer
Works
Magnetometer
Broken
Ambient Light
Works
Hall Effect
Works
Misc
HDMI/DP
Ir TX
Broken
Memory Card
Works
FOSS bootloader
Broken


Maintainer(s)

Users owning this device

  • Knuxify (Notes: SM-T310, 2x, mainlined!)
  • Lordkaczuha (Notes: (SM-T310) 2x one cracked but touch works other doesn't accept touch inputs afaikt. also have plenty of replacement parts if anybody wants some lol.)


How to enter flash mode

Enter download mode by holding down the Power and Volume down keys simultaneously until the download mode warning screen shows up, then press Volume up to dismiss the warning. (Holding down the home button is not necessary on this tablet, unlike on other Samsung devices.)

Installation

See Installation/Using pmbootstrap. This section contains the device-specific information related to installing with pmbootstrap.

In pmbootstrap init, select samsung-lt01 as the device. You will be prompted to select a variant:

  • wifi for the SM-T310;
  • 3g for the SM-T311;
  • lte for the SM-T315.

To flash the image, enter download mode by holding down the Power and Volume down keys simultaneously until the download mode warning screen shows up, then press Volume up to dismiss the warning.

Upgrading from old samsung-lt01wifi device package

Icon WARNING: This procedure is untested. It's preferable to re-install the OS from scratch if you plan to use the mainline kernel.

In the command line, run:

# apk add device-samsung-lt01 device-samsung-lt01-kernel-wifi linux-postmarketos-exynos4 device-samsung-lt01-nonfree-firmware

This should automatically reflash the boot image; if not, you may need to go through pmbootstrap installation, then run pmbootstrap flasher flash_kernel.

Reboot the device, then run:

# apk del device-samsung-lt01wifi linux-samsung-lt01wifi firmware-samsung-lt01wifi

Parts and their status

Note If the DRM driver crashes (screen gets stuck, lines start to get blurry/dimmer), power off the device immediately as leaving it on WILL (temporarily) damage your display! Usually the damage goes away after anywhere from a few minutes to about half an hour, but it's better to be safe.

Current issues:

  • RAM is limited to 1GB due to some weird quirks in how the later RAM is treated by the downstream kernel
  • Backlight forgets settings after suspend, resulting in choppy brightness changes
  • In Phosh, moving the mouse cursor around in landscape mode will cause the DRM driver to crash ("vblank wait timed out")
  • On one of my tablets, the screen sometimes has weird black lines on it; usually fixes itself on panel restart. Need to figure out if this is a hardware issue or if it could be worked around (the display seems to behave weirdly on startup too, maybe it's just the hardware...)

Fixed issues, but not yet in the repos:

  • Headset mic input doesn't work; jack detection doesn't work; patches have been partially merged upstream (the DTS parts are yet to be picked up) and will most likely make it into Linux 6.11, pending review on the exynos4-mainline side
  • Charging appears to be broken: being worked on in the tab3/otg-take-2 branch; patches are currently being upstreamed
  • USB OTG doesn't work (common issue for all Exynos 4 phones/tablets in mainline at the moment) - works in the aforementioned branch, needs cleanups and will be upstreamed soon

For the status of all components, see the tables below:

Element type Element Works? Notes
Chipset Exynos 4212 Y Used to be in mainline, but was dropped; reimplemented in the linked kernel fork
Graphics Mali-400MP4 Y
Charging IC max77693 P Supported in mainline; charging and OTG is broken at the moment.
Audio WM1811 P Speaker and headphone jack works (needs UCM config), internal mic works (but peaks - TODO), headset mic does not work. No automatic jack detection.
PMIC S5M8767 Y Supported in mainline
Fuel gauge MAX17050 Y Supported by MAX17042 driver
Touchscreen MELFAS MMS252 Y Pretty much identical to the other Melfas touchscreens in mainline. Using mms114 compatible for now. Both touchscreen and touch keys work.
Buttons gpio-keys Y Volume up/down, power and home button.
WiFi, Bluetooth BCM4334 Y Driver in mainline.
Display S6D7AA0 LSL080AL02 Y Driver in kernel fork. See also: Blog post about getting the display working
Backlight LP8556TMX Y PWM-controlled backlight controller. Seems to have a weird issue where setting it to 100% causes the backlight to shut down (though this is lazily worked around in my fork). Also seems to forget ROM settings after suspend.
Camera Sony ISX012 and Siliconfile SR130PC20 Both aren't in mainline
IR ABOV (Micom?) MC96FR332AUB The kernel option is IR_REMOCON_MC96, but REMOCON just seems to be Samsung's designation for remote controllers (given that they use it in part numbers for their TV remotes). The Kconfig description says it's a Micom(ABOV) device. It's an 8-bit microcontroller, programmed with a custom firmware bundled in the kernel as drivers/irda/irda_fw.h. Chip markings say ABOV 332AUB 1427. Also used on the GT-N8000. Official site/datasheet for what seems to be the same model
MHL sii9244 sii9234 driver seems to initialize fine, can't test because I don't own a dock; currently disabled, since this is the same chip as in the S3 and likely suffers from the same issues (phosh not starting up with dock unplugged)
Modem XMM6262 (3G), Qualcomm ??? (LTE) XMM6262 seems to be supported by replicant but isn't yet in mainline; Qualcomm modem might be MDM9615, since that's what the S3 4G uses; didn't check the code to make sure
GPS BCM47521 No clue about mainline support, seems to be unsupported

Sensors

Shared

Element type Element Works? Notes
Hall effect/flip cover sensor gpio-keys Y Simple sensor connected via GPIO.
Accelerometer STMicroelectronics K2DH Y Seems to be compatible with LIS2DH12
Magnetometer YAS532 P Enabled in DTS and seems to be detected, but the values don't seem to make much sense? TODO

WiFi

Element type Element Works? Notes
Light sensor CM3323 Y Driver in mainline

3G/LTE

Element type Element Works? Notes
"Grip sensor"? AD semiconductor ASP01 Appears to be a "Capacitive Touch/Proximity Sensor"; datasheet. Not 100% sure what this is used for.
Proximity sensor CM36653 Not in mainline; likely similar to CM36651

See also