psm(4) support for Elantech touchpads

[Matthias Apitz]

El día Monday, July 04, 2016 a las 11:55:08AM +0300, Vladimir Kondratyev escribió:

> After some investigations its turned out that some modern ElanTPs use 
> I2C interface not PS/2
> so they can not be handled with my patch. Its necessary to port new 
> driver from Linux
> https://lwn.net/Articles/496137/ or from OpenBSD where it has name 
> imt(4)

Thanks for your hint. I have to admit, that the idea it is an 'elan'
touchpad is at the moment only a guess. As I said, the Acer C720 was at
Acer.com for repair an issue with the touchpad and they changed the keyboard
and touchpad (this is an visible fact). ChromeOS was working with it but the call in
our FreeBSD src/sys/dev/cyapa/cyapa.c:

...
static int
cyapa_probe(device_t dev)
{
        struct cyapa_cap cap;
        int addr;
        int error;

        addr = smbus_get_addr(dev);

        /*
         * 0x67 - cypress trackpad on the acer c720
         * (other devices might use other ids).
         */

        device_printf(dev, "cyapa_probe(): addr %02x\n", addr);
        if (addr != 0x67)
                return (ENXIO);
        ...


now returns 0x15 and not 0x67, and so the cyapa.ko does not attach anymore
not even when I change the test to 0x15, which leaded to the guess of Elan TP.

I will try to make some NetBSD or OpenBSD USB boot key to first verify
what we do have here as hardware. Or any other idea to figure out, what
Acer now installed?

Thanks

	matthias

-- 
Matthias Apitz, ✉ guru at unixarea.de, ⌂ http://www.unixarea.de/  ☎ +49-176-38902045
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