On Wed, Jul 10, 2013 at 04:14:57PM +0100, Grant Likely wrote:

On Fri, 28 Jun 2013 07:19:06 -0600, Mathieu Poirier [off-list ref] wrote:

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On 13-06-28 12:09 AM, Dmitry Torokhov wrote:

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I do not agree.  We want the binding to be generic and not tied
specifically to the keyreset functionality.  As such 'input-keyset' or
'input-keychord' are more appropriate.

The binding is defined specifically for sysrq and specifically to
perform reset action.

Yes for now but as the examples in the binding show, it is easy to
envision how other drivers could use it.

I think you over-complicate things here. Unlike matrix-keypad binding,
where you have a common parsing code, here we have an individual driver.
I really do not see anyone else using such sequences or chords as such
processing should be done in userspace. Sysrq is quite an exception.

To be honest I don't have a very strong opinion on the binding.  I made
it as generic as possible on the guidance of the DT people.  Let's see
what they think of it.

Hi Mathieu,

As per our conversation just now at Connect, the binding should probably
look like this:

Sysrq keyset binding:

The /chosen node can contain a linux,input-keyset-sysrq child node to
define a set of keys that will generate a sysrq when pressed together.

Hmm, we would have only one such node, /sysrq, or /linux,sysrq,
whatever. The sysrq setting is system-wide and applicable to all
devices. Given that it is used only on mobile, where there not that
many input devices (a few keys and touchscreen) I do not believe we
should consider adding per-device settings.

Required properties:
keyset: array of keycodes

Please, let's call it 'key-reset-seq', because it is exactly the reset
sequence. There won't be any additional sequences or chords as those
should be handled in userspace, sysrq is a special case here.

timeout-ms: duration keys must be pressed together in microseconds
before generating a sysrq

Thanks.

-- 
Dmitry