From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

Trackpad HID device on T14s could be found on two possible slave addresses
(hid@15 and hid@2c) on i2c0 instance.
With the current state of DT boot, there is no way to patch the device
tree at runtime during boot. This, however results in non-functional
trackpad on Product Models 21N2ZC5PUS which have trackpad on hid@2c
slave address.

This patch adds hid@2c device along with hid@15 to get it working on
both the variants. This should work 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 setup 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 along with the parent pinctrl to solve this problem.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---

Changes since v2:
- updated commit log
- added missing parent pinctrl

 .../dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts  | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts
index 08ec2419f95f..5aa295404800 100644
--- a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts
+++ b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts
@@ -551,6 +551,9 @@ zap-shader {
 &i2c0 {
 	clock-frequency = <400000>;
 
+	pinctrl-0 = <&qup_i2c0_data_clk>, <&tpad_default>;
+	pinctrl-names = "default";
+
 	status = "okay";
 
 	/* ELAN06E2 or ELAN06E3 */
@@ -561,13 +564,19 @@ touchpad@15 {
 		hid-descr-addr = <0x1>;
 		interrupts-extended = <&tlmm 3 IRQ_TYPE_LEVEL_LOW>;
 
-		pinctrl-0 = <&tpad_default>;
-		pinctrl-names = "default";
-
 		wakeup-source;
 	};
 
-	/* TODO: second-sourced SYNA8022 or SYNA8024 touchpad @ 0x2c */
+	/* SYNA8022 or SYNA8024 */
+	touchpad@2c {
+		compatible = "hid-over-i2c";
+		reg = <0x2c>;
+
+		hid-descr-addr = <0x20>;
+		interrupts-extended = <&tlmm 3 IRQ_TYPE_LEVEL_LOW>;
+
+		wakeup-source;
+	};
 
 	/* ELAN06F1 or SYNA06F2 */
 	keyboard@3a {
-- 
2.39.2

On Fri, 04 Oct 2024 14:08:49 +0100, srinivas.kandagatla@linaro.org wrote:
> Trackpad HID device on T14s could be found on two possible slave addresses
> (hid@15 and hid@2c) on i2c0 instance.
> With the current state of DT boot, there is no way to patch the device
> tree at runtime during boot. This, however results in non-functional
> trackpad on Product Models 21N2ZC5PUS which have trackpad on hid@2c
> slave address.
> 
> [...]

Applied, thanks!

[1/1] arm64: dts: qcom: x1e80100-t14s: add another trackpad support
      commit: 8847c970ea06b4ab6f5d713a4adfe01982e4fa20

Best regards,
-- 
Bjorn Andersson <andersson@kernel.org>

On Fri, Oct 04, 2024 at 02:08:49PM +0100, Srinivas Kandagatla wrote:
> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> 
> Trackpad HID device on T14s could be found on two possible slave addresses
> (hid@15 and hid@2c) on i2c0 instance.
> With the current state of DT boot, there is no way to patch the device
> tree at runtime during boot. This, however results in non-functional
> trackpad on Product Models 21N2ZC5PUS which have trackpad on hid@2c
> slave address.
> 
> This patch adds hid@2c device along with hid@15 to get it working on
> both the variants. This should work 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 setup 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 along with the parent pinctrl to solve this problem.
> 
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> ---
> 
> Changes since v2:
> - updated commit log
> - added missing parent pinctrl

Thanks for the update. Looks good to me now:

Reviewed-by: Johan Hovold <johan+linaro@kernel.org>

On Fri, Oct 04, 2024 at 02:08:49PM GMT, srinivas.kandagatla@linaro.org wrote:
> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> 
> Trackpad HID device on T14s could be found on two possible slave addresses
> (hid@15 and hid@2c) on i2c0 instance.
> With the current state of DT boot, there is no way to patch the device
> tree at runtime during boot. This, however results in non-functional
> trackpad on Product Models 21N2ZC5PUS which have trackpad on hid@2c
> slave address.
> 
> This patch adds hid@2c device along with hid@15 to get it working on
> both the variants. This should work 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 setup 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 along with the parent pinctrl to solve this problem.
> 
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> ---
> 
> Changes since v2:
> - updated commit log
> - added missing parent pinctrl
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

-- 
With best wishes
Dmitry