Re: [PATCH 0/2] input/serio: Add a firmware_id sysfs attribute

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 03/28/2014 09:17 AM, Dmitry Torokhov wrote:
> On Fri, Mar 28, 2014 at 09:12:43AM +0100, Hans de Goede wrote:
>> Hi,
>>
>> On 03/28/2014 08:56 AM, Dmitry Torokhov wrote:
>>> On Thu, Mar 20, 2014 at 05:21:59PM +0000, Matthew Garrett wrote:
>>>> On Thu, Mar 20, 2014 at 11:12:08AM +0100, Hans de Goede wrote:
>>>>
>>>>> Which in the end turns out to be much nicer too, since it gets rid of needing
>>>>> a udev-helper too. After this much too long introduction I'll let the patches
>>>>> speak for themselves.
>>>>
>>>> Yeah, I was coming to the conclusion that this was probably the best we 
>>>> could do. It's unfortunate that "id" is already in use - we'd be able to 
>>>> get away without any X server modifications otherwise.
>>>>
>>>> Long term we probably still want to tie serio devices to the ACPI 
>>>> devices in case the vendor provides power management calls there, but we 
>>>> can leave that until there's an actual example.
>>>
>>> I am still unsure if we shoudl be adding these new IDs to serio core...
>>> Can't the X driver take a peek at ACPI devices on it's own?
>>
>> The problem is there is no way for userspace to know which /sys/devices/pnp0/00:xx
>> device is the serio bus host.
> 
> Practically speaking you should not care - there is only one touchpad in
> Lenovos.

So are you suggesting we simply go over all /sys/devices/pnp0/00:xx devices looking
for a pnp-id we're interested  in ?  I'm sorry but that is just a non-sense solution,
which reminds me of the good old days of random poking io-ports to probe stuff.

We're not blindly going to read every /sys/devices/pnp0/00:xx/id attribute on a
system, assuming that if it contains a pnp-id we're interested in it happens to
belong to the input device we're enumerating at that time.

Regards,

Hans