Re: [announce] mdevd-0.0.1.0 - a mdev-compatible uevent manager

From: Guillermo <gdiazhartusch_at_gmail.com>
Date: Wed, 15 Nov 2017 23:01:11 -0300

2017-11-15 14:11 GMT-03:00 Didier Kryn:
>
> I don't know what evdev is (I guess some virtual device) and what's its
> place in the big Xorg picture, but I think some of you guys know it. Any
> usefull link?

X11 comes in pieces; there is the server, normally installed as
/usr/bin/X and / or /usr/bin/Xorg, and modules, that e.g. Devuan
installs in /usr/lib/xorg/modules, I believe, and that include the
video drivers (/usr/lib/xorg/modules/drivers) and input drivers
(/usr/lib/xorg/modules/input). Evdev an input driver (i.e. it handles
the keyboard, mouse, etc.) that IIUC uses Linux' event interface
(CONFIG_INPUT_EVDEV, "Say Y here if you want your input device events
be accessible under char device 13:64+ - /dev/input/eventX in a
generic way").

You can see which modules are loaded by X at startup in its log file
(normally /var/log/Xorg*.log), and if your computer has the package
that provides the evdev driver installed, see 'man evdev'.

2017-11-15 11:53 GMT-03:00 Laurent Bercot:
>
> Is it really the only place in Xorg that depends on libudev?
> I'd think it would be much, much more entangled with libudev than
> this.

Indeed it is. The X server itself:

* https://cgit.freedesktop.org/xorg/xserver/tree/config/udev.c

The modesetting video driver:

* https://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/drivers/modesetting/drmmode_display.c
(drmmode_*uevent*())

The Intel video driver:

* https://cgit.freedesktop.org/xorg/driver/xf86-video-intel/tree/src/uxa/intel_driver.c
(I830*UEvent*())

The amdgpu video driver:

* https://cgit.freedesktop.org/xorg/driver/xf86-video-amdgpu/tree/src/drmmode_display.c
(drmmode_*uevent*())

And probably more. Although it seems that in most cases the dependency
on the libudev API is selectable by an option at compile time.

G.
Received on Thu Nov 16 2017 - 02:01:11 UTC

This archive was generated by hypermail 2.3.0 : Sun May 09 2021 - 19:38:49 UTC