[ Upstream commit a9164910 ]

Indicated by AML code in ACPI table, the touchpad in-use could be found
on two possible slave addresses on &i2c3, i.e. hid@15 and hid@2c.  And
which one is in-use can be determined by reading another address on the
I2C bus.  Unfortunately, for DT boot, there is currently no support in
firmware to make this check and patch DT accordingly.  This results in
a non-functional touchpad on those C630 devices with hid@2c.

As i2c-hid driver will stop probing the device if there is nothing on
the slave address, we can actually keep both devices enabled in DT, and
i2c-hid driver will only probe the existing one.  The only problem is
that we cannot set up pinctrl in both device nodes, as two devices with
the same pinctrl will cause pin conflict that makes the second device
fail to probe.  Let's move the pinctrl state up to parent node to solve
this problem.  As the pinctrl state of parent node is already defined in
sdm845.dtsi, it ends up with overwriting pinctrl-0 with i2c3_hid_active
state added in there.

Fixes: 11d0e4f2

 ("arm64: dts: qcom: c630: Polish i2c-hid devices")
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20210102045940.26874-1-shawn.guo@linaro.org


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>