Linux Kernel v5.3 released, our contributions

BayLibre has continued our contribution to the Linux community as seen with this new version of Linux Kernel 5.3, released on Sunday, September 15th 2019.  An excellent summary of this release can be found at KernelNewbies.

If you check out LWN.net’s 5.3 Kernel development cycle statistics article, you’ll see that BayLibre made it onto the top 20 contributors list, showing that we were one of the most active companies (when measured by changes) this development cycle.

Here is a summary of our contributions, organized by SoC family and a summary graph of contributions by developer.

AmLogic SoCs

This release we contributed heavily to Amlogic Meson SoCs mainline support with lots of work from Neil Armstrong, Jerome Brunet, and Maxime Jourdan for the G12A (S905X2/S905D2) and G12B SoCs including:

  • Initial support for new G12B Soc family 
  • Enabling the IR controller on the SEI510, u200, and X96 Max boards
  • Fixups for the AXG TDM formatter driver
  • Adding support for dynamic OTG switching with the ID change interrupt
  • Enabling the sound card on the Hardkernel Odroid-N2
  • Increasing the Bluetooth bus speed to 2Mbaud/s
  • Enabling the WiFi SDIO module
  • Adding gigabit ethernet support for the X96 Max board
  • Enabling the hwrng module for the next generation SM1 SoC family
  • Enabling SD and eMMC on the g12a u200 board
  • A V4L2 m2m video decoder driver
  • Support for the XBGR8888 and ABGR8888 formats to the graphics controller

GPIO subsystem

Bartosz Golaszewski contributed changes for the GPIO subsystem including:

  • Fixes for warnings when the gpiolib is disabled
  • A fix for a use-after-free bug 
  • Various other cleanups and fixes

RISC-V

With the continued interest and adoption of RISC-V, we wanted an easy way to build an upstream kernel for the SiFive Unleashed board. Loys Ollivier submitted a patch that enables support in the default RISC-V kernel config.

DaVinci SoC

We’ve talked about updating the existing TI DaVinci SoC timer driver in the past, and this release Bartosz Golaszewski implemented a much simpler — and more modern — version with clockevents and clocksource support. He also enabled cpufreq support.

Misc

Beyond the above, we’ve also contributed patches to various subsystems and drivers.

  • Jerome Brunet contributed miscellaneous fixes and cleanups for the ASoC subsystem
  • Fabien Parent added AUDSYS clock support for MediaTek’s MT8516 SoC
  • Neil Armstorng enabled the Lima driver (ARM Mali 400/450 GPU) for arm64 and ARMv7 boards because it will be useful for KernelCI boot and runtime testing. 
  • Bartosz Golaszewski contributed cleanup patches for the at24 EEPROM driver and a new selector stepping option for voltage regulators.

BayLibre Linux 5.3 contributions