[Bug 1864147] Re: [bionic] Support Intel Atom (Baytrail-I) HS-UART serdev slaves over tty

The task "linux (Ubuntu)" has expired because it has had no new comments or updates for more than three years. If this issue is still present in an Ubuntu LTS kernel still under active support, please reopen the bug and provide updated details. If this issue was reported against an Ubuntu kernel no longer under active support but the issue still exists in a currently supported Ubuntu kernel, please open a new bug against that kernel version and provide the updated details, with a reference link to the original bug. This action was performed by an automated process maintained by the Ubuntu Kernel Team. ** Tags added: kernel-autoclosed kernel-autoclosed-expired ** Changed in: linux (Ubuntu) Status: Confirmed => Expired -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/1864147 Title: [bionic] Support Intel Atom (Baytrail-I) HS-UART serdev slaves over tty Status in linux package in Ubuntu: Expired Status in linux source package in Bionic: Expired Bug description: [SRU Justification] [Impact] Support Intel Atom (Baytrail-I) HS-UART serdev slaves over tty On systems using Intel Atom (Baytrail-I) SoC's, slave devices connected on HSUART1/2 ports are described by the ACPI BIOS as virtual hardware using HID's INT3511/INT3512. As a consequence, HW manufacturers have complete freedom to install any devices on-board as long as they can be accessed over serial tty interface. Once such device is Dell Edge 3002 IoT Gateway which sports ZigBee & GPS devices on the HS-UART ports 1 & 2 respectively. Post 4.15, with CONFIG_SERIAL_DEV_BUS=y, serdev port controller driver handles the enumeration for the slaves connected on these ports. Also, /dev/ttySx device nodes for these ports are no longer exposed to the userspace. [Fixes] This patchset allows the skipped virtual UART's with ACPI HID's mentioned above to be enumerated as ttyHSx port. [Regression Potential] Low. This driver binds only to Intel Atom E38XX (Baytrail-I) virtual serial ports on the Dell Edge 300x GW. These updates are being carried in the linux-oem (4.15.y) kernel for more than 2 years without any regressions. [Note] This driver has been submitted upstream and is under review. This issue has been identified as a regression in 4.15 and multiple solutions are being explored. Meanwhile, to support customer and maintain release schedule, this driver needs to be in Ubuntu 4.15 based kernels. More info: https://marc.info/?t=152455871600007&r=1&w=2 linux-oem buglink: http://bugs.launchpad.net/bugs/1690362 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1864147/+subscriptions