Jump to content

Xiaomi Redmi 4X (xiaomi-santoni)

From postmarketOS Wiki
Revision as of 05:42, 21 April 2021 by Shadowsvanish (talk | contribs) (Added section of UART)
Xiaomi Redmi 4x
xiaomi-santoni running pmOS demos
xiaomi-santoni running pmOS demos
Manufacturer Xiaomi
Name Redmi 4x
Codename xiaomi-santoni
Released 2017
Hardware
Chipset Qualcomm MSM8940 Snapdragon 435
CPU Octa-core 1.4 GHz Cortex-A53
GPU Adreno 505
Display 720x1280
Storage 16 GB / 32 GB / 64GB
Memory 2 GB / 3 GB / 4 GB
Architecture aarch64
Software
Original software Android 6.0 (can be upgradable to 7.1)
postmarketOS
Category testing
Pre-built images no
postmarketOS kernel 3.18.140
Unixbench Whet/Dhry score 1526.7
Features
Flashing
Works
USB Networking
Works
Internal storage
No data
SD card
No data
Battery
Works
Screen
Works
Touchscreen
Works
Multimedia
3D Acceleration
No data
Audio
Works
Camera
Broken
Camera Flash
No data
Connectivity
WiFi
Works
Bluetooth
Partial
GPS
No data
NFC
No data
Modem
Calls
No data
SMS
No data
Mobile data
No data
Miscellaneous
FDE
Partial
USB OTG
Works
HDMI/DP
No data
Sensors
Accelerometer
No data
Magnetometer
No data
Ambient Light
No data
Proximity
No data
Hall Effect
No data
Haptics
No data
Barometer
No data


Contributors

  • pinoaffe
  • asriel-danctnix
  • Danct12

Maintainer(s)

  • Danct12

Users owning this device


What works

  • Install to SD Card
  • Boots
  • Flashing
  • Touch
  • Wayland
  • XWayland
  • USB Ethernet/Internet
  • WiFi
  • Vibrator
  • Audio
  • Xorg
  • USB OTG
  • charging-sdl

What does not work

  • Camera
  • GPS
  • Mobile Data
  • SMS
  • Calls
  • Accelerometers
  • Bluetooth (partially)
  • 3D Acceleration (possible on mainline)
  • Display Power Management on Wayland
  • Full Disk Encryption (does unlock, but failed to look up the partition after booting)

Bugs?

  • alsamixer doesn't work, will result in a error telling mixer controls doesn't exist, workaround to control the volume is to use PulseAudio.

Mainline kernel?

There's ongoing effort to bring up mainline kernel on MSM8937 platform, with initial focus on santoni: [1].

MSM8937/40 is pretty close to MSM8916, so a lot of drivers can be re-used with proper device tree and minimal address remapping in some places.

Parts Components In Torvalds tree?
Chipset MSM8940 No
GPU Adreno 505 Yes (a5xx_gpu.c)
Touch Screen FT5X06 Yes (edt-ft5x06.c)
Fingerprint Sensor FPC1020/Goodix No
Accelerometer + Gyroscope ICM20607/BMI120 No/Yes (bmi160_i2c.c)
ALSPS STK3X1X Yes (stk3310.c)
Magnetometer YAS537 No
Sound AW87319 No
Notifications LED AW2013 Yes (leds-aw2013.c)
Front Camera OV5675 Yes (ov5675.c)
Back Camera S5K3L8 No

More information on this port

Bootloader Unlocking

Like other Xiaomi devices, the user will have to acquire the bootloader unlock key: https://en.miui.com/unlock

The device will not unlock if the device isn't 7 days old (from the time when your device connects to internet and powered on)

Key combinations for entering Recovery/Fastboot

Recovery

  • Turn the device off (or restart also works)
  • Hold both volume buttons (+ and -) and power button
  • Keep holding until you got to recovery.

Fastboot

  • Same as recovery, but this time hold the volume down key instead of both keys.

Installation

Installation over fastboot works, Android recovery zip installation is untested.

Bluetooth

Bluetooth on this phone is using the WCNSS chip, which provides two SMD channels to the BT core, one for command and one for event packets. Support for Bluetooth HCI SMD can be added using this patch.

With that patch applied, the Bluetooth interface can be bring up by set /sys/module/hci_smd/parameters/hcismd_set to 1. Then install bluez, start the service and use bluetoothctl to control it.

As right now, it seems to connect, but disconnect very quickly, it doesn't ask for pair code when connecting, so this needs to be investigated.

Serial Connection (UART)

The Serial Connection of the santoni has been tested only on reception mode, with 3.3v TTL to USB FT232RL. This example is an output when starting to fastboot.

Warning: the test point is very small, try to solder only if you're an expert on soldering.

Wiring: (Santoni TX --> FT232RL RX) and (Santoni GND --> FT232RL GND)

Photos

See also