Re: 2.6.0-test4, psmouse doesn't autoload, CONFIG_SERIO doesn't module

["\"Andrey Borzenkov\" " <arvidjaar@mail.ru>]

> 1. Why doesn't the PS/2 mouse autoload as a module?
> Running 2.6.0-test4, psmouse doesn't autoload as a module.  Oddly,  neither
> gpm nor X complains about the missing module, the mouse just doesn't work.
> But if I modprobe psmouse, the cursor starts moving.  I verified that
> /dev/psaux uses char-major-10-1 and that it has an "alias char-major-10-1
> psaux" in modprobe.conf.

because in 2.6 user-level programs do not speak with low-level hardware
drivers anymore. psmouse feeds events to input midlayer that dispatches
them to those handlers that expressed interest. And those handlers speak
with user-level tools.

/dev/psaux is an *emulated* ImPS mouse that is not related to any
real hardware. It will convert events from _any_ mouse you have into
PS/2 protocol for users but if there is no mouse it just sits there
and waits.

/dev/psaux is provided by mousemod not psmouse.

In general there seems to be no way to load low-level input drivers
on access because there is no instance that ever accesses them. And
as it stands now there is not way to auto-load using some other means.
So we are back in static configuration times ...

> 1. What does kmod send to modprobe?  From looking at modprobe.conf apparently "char-major-x-y".

only for misc devices. It is char-major-X for most others

> 2. Does kmod send any other strings to modprobe?

no.

> 3. Documentation/kmod.txt says "passing the name (to modprobe) that was
> requested", couldn't this be more explicit?

what exactly do you mean?

> 4. Does kmod gets the major-minor number from the device file upon open(),
> or some other way?

from device file on open.

-andrey

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> 1. Why doesn't the PS/2 mouse autoload as a module?
> Running 2.6.0-test4, psmouse doesn't autoload as a module.  Oddly,  neither
> gpm nor X complains about the missing module, the mouse just doesn't work.
> But if I modprobe psmouse, the cursor starts moving.  I verified that
> /dev/psaux uses char-major-10-1 and that it has an "alias char-major-10-1
> psaux" in modprobe.conf.

because in 2.6 user-level programs do not speak with low-level hardware
drivers anymore. psmouse feeds events to input midlayer that dispatches
them to those handlers that expressed interest. And those handlers speak
with user-level tools.

/dev/psaux is an *emulated* ImPS mouse that is not related to any
real hardware. It will convert events from _any_ mouse you have into
PS/2 protocol for users but if there is no mouse it just sits there
and waits.

/dev/psaux is provided by mousemod not psmouse.

In general there seems to be no way to load low-level input drivers
on access because there is no instance that ever accesses them. And
as it stands now there is not way to auto-load using some other means.
So we are back in static configuration times ...

> 1. What does kmod send to modprobe?  From looking at modprobe.conf apparently "char-major-x-y".

only for misc devices. It is char-major-X for most others

> 2. Does kmod send any other strings to modprobe?

no.

> 3. Documentation/kmod.txt says "passing the name (to modprobe) that was
> requested", couldn't this be more explicit?

what exactly do you mean?

> 4. Does kmod gets the major-minor number from the device file upon open(),
> or some other way?

from device file on open.

-andrey