[PATCH v3] arm64: dts: qcom: glymur-lenovo-yoga-slim7x: add the camera privacy switch

[PATCH v3] arm64: dts: qcom: glymur-lenovo-yoga-slim7x: add the camera privacy switch

[Oleg Keri]

The laptop has a camera privacy switch on the side of the top case - a
slider, not a mechanical cover over the lens, and it does nothing to the
camera itself. TLMM gpio99 follows its position: high with the switch
open, low with it engaged. Describe it as a gpio-keys switch so userspace
can act on it.

SW_CAMERA_LENS_COVER is the only switch code the input layer has for a
camera privacy state, and it is what the Lenovo WMI camera driver and
Dell's privacy driver report for the same kind of electronic switch on
x86 machines, so use it here as well despite the name.

The embedded controller also raises event 0x29 whenever the switch
moves, which makes it tempting to report it from the EC driver instead.
That would be the wrong layer: the pin is a plain level that tracks the
slider position and needs no EC transaction to read, and the EC event
carries nothing the pin does not already say.

Signed-off-by: Oleg Keri <okerixx@gmail.com>
---
Changes in v3:
- v2 went out with its subject header swallowing the first paragraph of
  the message, a mistake in how I generated the mail; no change to the
  patch itself.
- Link to v2: https://lore.kernel.org/all/20260914092802.12315-1-okerixx@gmail.com/

Changes in v2:
- Capitalize the switch label (Konrad).
- Put the pin state where the GPIO index sorts it, between gpio94 and
  gpio111, instead of after the trackpad state (Konrad).
- Link to v1: https://lore.kernel.org/all/20260914081652.5935-1-okerixx@gmail.com/

 .../boot/dts/qcom/glymur-lenovo-yoga-slim7x.dts   | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/glymur-lenovo-yoga-slim7x.dts b/arch/arm64/boot/dts/qcom/glymur-lenovo-yoga-slim7x.dts
index ecc8c34fb983..769f195c99d9 100644
--- a/arch/arm64/boot/dts/qcom/glymur-lenovo-yoga-slim7x.dts
+++ b/arch/arm64/boot/dts/qcom/glymur-lenovo-yoga-slim7x.dts
@@ -51,7 +51,7 @@ sleep_clk: sleep-clk {
 	gpio-keys {
 		compatible = "gpio-keys";
 
-		pinctrl-0 = <&hall_int_n_default>;
+		pinctrl-0 = <&hall_int_n_default>, <&cam_privacy_default>;
 		pinctrl-names = "default";
 
 		switch-lid {
@@ -62,6 +62,13 @@ switch-lid {
 			wakeup-source;
 			wakeup-event-action = <EV_ACT_DEASSERTED>;
 		};
+
+		switch-camera-privacy {
+			label = "Camera privacy switch";
+			gpios = <&tlmm 99 GPIO_ACTIVE_LOW>;
+			linux,input-type = <EV_SW>;
+			linux,code = <SW_CAMERA_LENS_COVER>;
+		};
 	};
 
 	leds {
@@ -1012,6 +1019,12 @@ wcn_sw_en: wcn-sw-en-state {
 		bias-disable;
 	};
 
+	cam_privacy_default: cam-privacy-default-state {
+		pins = "gpio99";
+		function = "gpio";
+		bias-pull-up;
+	};
+
 	cam_indicator_en: cam-indicator-en-state {
 		pins = "gpio111";
 		function = "gpio";
-- 
2.55.0

base-commit: 68142f986ff04b2b70b31db00f719bf690f64a9a