Re: [RFC/RFT] Raw access to serio ports (2/2)

From: Dmitry Torokhov
Date: Wed Jun 02 2004 - 07:35:13 EST


On Wednesday 02 June 2004 04:49 am, Sau Dan Lee wrote:
> >>>>> "Dmitry" == Dmitry Torokhov <dtor_core@xxxxxxxxxxxxx> writes:
>
> Dmitry> +static unsigned int i8042_aux_raw[4];
>
> So, only AUX ports can be directly accessed? No direct access to
> keyboard port? Why?
>

Keyboards are to be handled in-kernel, at least for now. If there really
a need we can enable grabbing keyboard as well, no big deal.

> The SERIO_USERDEV patch does allow direct access to the PC AT
> keyboard, and it did help me locate the SysRq problem that I reported
> in other postings. i.e. it IS useful to be able to access the
> keyboard port directly.
>

Vojtech has a patch for that - now raw (really raw) codes are reported via
EV_MSC/MSC_RAW event.

>
> Dmitry> The driver will happily co-exist with psmouse and atkbd
> Dmitry> loaded as they ignore SERIO_8042_RAW ports, so it is
> Dmitry> possible to have one AUX port in raw mode and other in
> Dmitry> standard 2.6 mode.
>
> 1) there is no RAW access to the keyboard port;
>
> 2) I hate this black magic, in which the input "devices"
> (i.e. drivers) kidnap the serio ports they like according to the
> port type SERIO_8042_RAW, etc. That's a kind of hardcoding the
> binding between ports and drivers.

We do have some hardcoding so atkbd does not try to grab a serio linked
to a serial port and sermouse does not try grabbing keyboard port, etc..
There is nothing new.

>
>
> Isn't it better to leave the AUX ports as SERIO_8042, and let the user
> dynamically change this port<-->driver binding? Then, we don't even
> need that ugly "i8042.raw" boot parameter or i8042_aux_raw option.
> The user can decide which ports are connected to your serio_raw
> driver, and which ports are connected to psmouse.ko. That would also
> allow multiple drivers driving the ports of the same type.
>

Yes, that's the perfect solution, but I believe we need sysfs for that
and at least I started working on it, but it takes time. In the meantime
i8042.raw should alleviate most of the user's troubles with their input
devices no longer working.

--
Dmitry
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