Re: [PATCH v5 2/2] Input: hideep - Optionally reset controller work mode to native HiDeep protocol

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Sat, Mar 11, 2023 at 12:47:26PM +0100, Hans de Goede wrote:
> The HiDeep IST940E touchscreen controller used on the Lenovo Yoga Book X90F
> convertible comes up in HID mode by default.
> 
> This works well on the X91F Windows model where the touchscreen is
> correctly described in ACPI and ACPI takes care of controlling
> the reset GPIO and regulators.
> 
> But the X90F ships with Android and the ACPI tables on this model don't
> describe the touchscreen. Instead this is hardcoded in the vendor kernel.
> 
> The vendor kernel uses the touchscreen in native HiDeep 20 (2.0?) protocol
> mode and switches the controller to this mode by writing 0 to reg 0x081e.
> 
> Adjusting the i2c-hid code to deal with the reset-gpio and regulators on
> this non devicetree (but rather broken ACPI) convertible is somewhat tricky
> and the native protocol reports ABS_MT_PRESSURE and ABS_MT_TOUCH_MAJOR
> which are not reported in HID mode, so it is preferable to use the native
> mode.
> 
> Add support to the hideep driver to reset the work-mode to the native
> HiDeep protocol to allow using it on the Lenovo Yoga Book X90F.
> This is guarded behind a new "hideep,force-native-protocol" boolean
> property, to avoid changing behavior on other devices.
> 
> For the record: I did test using the i2c-hid driver with some quick hacks
> and it does work. The I2C-HID descriptor is available from address 0x0020,
> just like on the X91F Windows model.
> 
> So far the new "hideep,force-native-protocol" property is only used on
> x86/ACPI (non devicetree) devs. IOW it is not used in actual devicetree
> files. The devicetree-bindings maintainers have requested properties like
> these to not be added to the devicetree-bindings, so the new property is
> deliberately not added to the existing devicetree-bindings.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Applied, thank you.

-- 
Dmitry