Re: Getting notification of PS/2 mouse packages

On Fri, Aug 05, 2011 at 01:35:55PM +0200, Michael Thayer wrote:

Hello,

I am looking at writing a driver (it is to be open source, but not for
mainstream kernel inclusion) for a virtual machine-specific input
device.  Unfortunately one of the versions of the device I have to
support signals that it has new data available by sending a fake package
to the PS/2 mouse, so I need to be able to get notification of that
somehow.  Looking at the kernel source, I see that the i8042 driver
requests IRQ 12 as IRQF_SHARED, and that the kernel always notifies all
registered interrupt handlers of an interrupt, even if one of them
returns IRQ_HANDLED.  So it looks like I can just request my own shared
handler for IRQ 12 and always return IRQ_NONE, but still update my data.
However I am not sure whether this is something I can count on to keep
working in future kernel releases.  Does anyone on this list know more
about this, or can someone suggest a cleaner way to get the
notifications I need?

Thanks.

Regards,

Michael

Hello, Michael.

My advice is: send it for mainline inclusion!

You more likely get your code reviewed, and it what you do is
acceptable, it will get included and that's a "OK" for your solution.
Then, if it turns out it's not OK anymore, it's much more likely people
will go and fix it for you. At least, that's certainly not going to
happen if it's not published somehow, but out-of-tree drivers or patches
do not usually have the attention of Linux developers.

So, what is it that you consider your work not worth of mainline
inclusion?

Regards,
Cascardo.

-- 
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