Samsung Galaxy Tab 10.1" (samsung-p4wifi)
postmarketOS for the Samsung Galaxy Tab 10.1 runs on mainline Linux kernel fork. The kernel uses both mainline and forward ported drivers. Some peripherals are using mainline device driver where applicable. Some peripherals which are not working on or don't have mainline drivers are using drivers forward ported from the stock 3.1.10 kernel.
How to enter flash mode
Press and hold Power + Volume Down buttons
- Init pmbootstrapChoose 'samsung-p4wifi' as target device.
$ ./pmbootstrap.py init
- Start the build process
$ ./pmbootstrap.py build linux-samsung-p4wifi $ ./pmbootstrap.py build device-samsung-p4wifi $ ./pmbootstrap.py install --no-fde
- Enter flash (download) mode
- Flash the kernel and system images
$./pmbootstrap.py flasher flash_kernel $./pmbootstrap.py flasher flash_rootfs
The battery in this device is the
max17042. A tear down of the (nearly) identical Galaxy Tab 8.9 reveals that the charger is
Differences between mainline and downstream drivers:
The downstream kernel provides an early implementation of a driver for the
max17042 battery. The implementation of the battery and charger driver are split across
max17042_battery.c. The downstream charger driver implements additional logic to handle charge full and low battery events which may affect the health of the battery. The implementation details are not clear but the overall functionality appears to dynamically tune the full charge value. The mainline driver does not have this sort of functionality. The downstream driver reports the current in milliamp whereas the mainline driver is in microamp.
max8903 datasheet shows that there are separate GPIOs for USB and DC power connectors. This device has one connect GPIO for both USB and DC mode. The type of connector is determined by reading the
usb-sel GPIOs. It's unclear which piece of hardware the usb-sel is coming from (max8903 / tegra soc / 30-pin connector ???).
The reverse engineer grate-driver provides 2D acceleration on X11. 3D acceleration is not implemented. This means that Xfce4 and Mate desktop will work. Hildon requires an OpenGL backend. Wayland UIs will only work with the framebuffer driver.
grate-drver packaging can be found at: https://gitlab.com/ryang2678/pmaports/tree/feature/grate-driver
Video Decoder Engine (VDE) was added to mainline kernel v4.16. The grate-driver includes hardware h264 decoding with libvdpau-tegra.
Headphone and speaker output are working on the mainline wm8994 driver. Microphone inputs are not working.
The ALSA UCM config files were generated using the
xml2ucm tool. The
p4wifi.config.xml can be found in this github gist.
$ stack exec -- xml2ucm -m mixer_paths.xml -c p4wifi-config.xml -o examples
The wifi chip in this device is the Broadcom BCM4330 B1 revision. There is a B2 revision which is much more common. The only distinguishing factor is the firmware. Only the B1 firmware will work on this device. The most common BCM4330 firmware found from various sources (such as
linux-firmware) is for the B2 revision.
The xmm6260 modem was used in quite a few Samsung Android devices from the same era as this tablet. The Samsung Galaxy Tab 10.1 3G (p4) and Samsung Galaxy Tab 10.1 from T-Mobile (p4tmo) are otherwise identical to the WiFi only version of the tablet (p4wifi). The cellular modem is connected via an internal USB interface called USB HSIC. The mainline Tegra USB driver does not implement this functionality. Much of the work in enabling the cellular stack would involve adding USB HSIC support to the mainline USB driver.
Hardware Information & Mainline Driver Status
The Linux mainlining effort contains drivers forward ported from the stock Samsung Linux 3.1.10 kernel which shipped with the device. Some peripheral devices have been transitioned over to the mainline driver. Other drivers are not in the mainline kernel or the device is not compatible with the mainline driver.
|Peripheral Type||Hardware|| Mainline Driver|
|Ambient light sensor||bh1721fvc||Y|
|Analog Digital Converter||stmpe811||Y|
|CPU Temperature Sensor||nct1008||Y|
|Wifi / Bluetooth||bcm4330||Y|
|30-pin accessory port||unknown||-|
- 1: kxt9f driver exists in mainline. The driver needs support device tree bindings.
- 2: ak8975 driver exists in mainline. The device id for ak8975c needs to be added to the driver. I (decatf) can't test it because the compass seems to report nonsense data. The compass on my tablet might be broken.
- 3: sii9234 driver exists in mainline. Requires someone with an MHL cable to implement / test it.
Mainline Driver Status Legend
|P||Forward ported driver|
|-||No driver -- driver has not been forward ported|