On Sun, Feb 10, 2019 at 12:36:44PM +0100, Bastien Nocera wrote:
> Hey,
>
> On Sun, 2019-02-10 at 13:30 +0300, Yauhen Kharuzhy wrote:
> > Some variants of Goodix touchscreen firmwares use 9-bytes finger
> > report format instead of common 8-bytes format.
> <snip>
> > +static const struct dmi_system_id nine_bytes_report[] = {
> > +#if defined(CONFIG_DMI) && defined(CONFIG_X86)
> > + {
> > + .ident = "Lenovo YogaBook",
> > + /* YB1-X91L/F and YB1-X90L/F */
> > + .matches = {
> > + DMI_MATCH(DMI_PRODUCT_NAME, "Lenovo YB1-X9")
> > + }
> > + },
> > +#endif
> > + {}
> > +};
>
> Is this really the only way to know whether the report is 8 or 9 bytes?
> Which Goodix model is it? Can you find additional information about the
> protocol in the specifications[1]
>
I didn't find any way. Driver from Lenovo has 9-byte format hardcoded[1,2] and
I cannot find any mention of such format in the datasheet. Maybe (VendorID +
Firmware version) combination will be suitable as key for detection of
this case but I think that it is almost the same as using of DMI product ID.
YogaBook seems to have GT9110 chip.
I can dump the config and FW vendor & version and publish them for checking soon.
1. https://github.com/jekhor/yogabook-linux-android-kernel/blob/b7aa015ab794b516da7b6cb76e5e2d427e3b8b0c/drivers/input/touchscreen/gt9xx/gt9xx.c#L912
2. https://github.com/jekhor/yogabook-linux-android-kernel/blob/b7aa015ab794b516da7b6cb76e5e2d427e3b8b0c/drivers/input/touchscreen/gt9xx/gt9xx.h#L52
--
Yauhen Kharuzhy
