Re: [PATCH v3 2/3] HID: quirks: Fix keyboard + touchpad on Lenovo Miix 630 for DT

[Hans de Goede]

Hi,

On 18-04-19 11:34, Benjamin Tissoires wrote:
> On Mon, Apr 15, 2019 at 6:11 PM Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx> wrote:
> > Following up on commit 2bafa1e96254 ("HID: quirks: Fix keyboard + touchpad
> > on Lenovo Miix 630"), the devicetree (DT) identifier for the combo keyboard
> > + touchpad device is "elan,combo400-i2c", which differs from the ACPI ID,
> > thus if we want the quirk to work properly when booting via DT instead of
> > ACPI, we need to key off the DT id as well.
> >
> > Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx>
> > ---
> >   drivers/hid/hid-quirks.c | 3 ++-
> >   1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/hid/hid-quirks.c b/drivers/hid/hid-quirks.c
> > index 77ffba48cc73..00c08f8318b8 100644
> > --- a/drivers/hid/hid-quirks.c
> > +++ b/drivers/hid/hid-quirks.c
> > @@ -997,7 +997,8 @@ bool hid_ignore(struct hid_device *hdev)
> >                          return true;
> >                  /* Same with product id 0x0400 */
> >                  if (hdev->product == 0x0400 &&
> > -                   strncmp(hdev->name, "QTEC0001", 8) != 0)
> > +                   (strncmp(hdev->name, "QTEC0001", 8) != 0 ||
> > +                    strncmp(hdev->name, "elan,combo400-i2c", 17) != 0))
>
> I think we are taking the problem the wrong way here.
>
> When I first introduced 6ccfe64, I thought 0x0400 would be reserved
> for the elan_i2c touchpads only. But it turns out we are deliberately
> disabling valid HID touchpads hoping that they would be picked up by
> elan_i2c when elan_i2c has its own whitelist of devices.
>
> How about we turn this into list with the matching ones from elan_i2c:
> if ((hdev->product == 0x0400 || hdev->product == 0x0401) &&
>     (strncmp(hdev->name, "ELAN0000", 8) == 0 ||
>      strncmp(hdev->name, "ELAN0100", 8) == 0 ||
>      ...
>      strncmp(hdev->name, "ELAN1000", 8) == 0))
>        return true;
>
> So next time we need to force binding a HID touchpad to elan_i2c, we
> can just blacklist here and whitelist it in elan_i2c.

This indeed sounds like a better way forward with this.

Regards,

Hans