Accessibility (Kernel)

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Introduction

In order to support accessibility packages, some kernel modifications may be needed. Some of these can be made at the level of Alpine Linux or pmOS; others will need to be made separately for each supported device.

Status

Serial Adapters

Dave Mielke (BRLTTY's developer) says: It'd be very cool for the kernel to have support for all known USB-to-serial adapters, plus any indirectly needed serial support, enabled. That way, those with older braille devices that only have a serial port would benefit for the mere extra cost of the adapter cable. Sure would beat having to purchase a newer braille device.

Martijn Braam says: It depends on the device, of course, but I don't think adding support for USB-serial adapters would be a problem. I already did that to test some things on the PinePhone. I guess enabling prolific, ftdi, and ch340 would cover most adapter cables. Unfortunately, it would be a per-device kernel tweak. I'm not sure how many devices have USB serial support built in already. The allwinner kernel only has CH341 support currently. It looks like the generic driver is 14.4KB and ch341 adds 4.7KB. Serial drivers aren't really big... (The drivers are all listed under drivers/usb/serial in the kconfig utility.)

SSH over Wi-Fi

All devices running the mainline kernel appear to have Wi-Fi support and sshd enabled. So, in order to log in remotely, one should simply need to determine the IP address and then use the default username/password combo to log in.

Virtual Console

Many forms of assistive technology make use of a virtual console:

A virtual console (VC) – also known as a virtual terminal (VT) – is a conceptual combination of the keyboard and display for a computer user interface. It is a feature of some Unix-like operating systems such as BSD, Linux, illumos and UnixWare in which the system console of the computer can be used to switch between multiple virtual consoles to access unrelated user interfaces.

Virtual console support (CONFIG_VT) is required to boot pmOS. So, it should be supported on any device running the mainline kernel. That said, problems have been reported (e.g., with version 4.4).

Resources