[PATCH V5 3/4] arm64: dts: qcom: sc7180-trogdor: Add pinctrl and interrupt config for BT UART

[satya priya]

Add a suitable sleep configuration for uart3 to support Bluetooth wakeup.

If QUP function is selected in sleep state, UART RTS/RFR is pulled high
during suspend and BT SoC not able to send wakeup bytes. So, configure
GPIO mode in sleep state to keep it low during suspend.

Signed-off-by: satya priya <skakit@xxxxxxxxxxxxxx>
---
Changes in V5:
 - Newly added in V5. This patch adds wakeup support for trogdor board files.

 arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 48 ++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
index a6b9beb..96b5331 100644
--- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
@@ -792,6 +792,11 @@ ap_spi_fp: &spi10 {
 #include <arm/cros-ec-sbs.dtsi>
 
 &uart3 {
+	pinctrl-names = "default", "sleep";
+	pinctrl-1 = <&qup_uart3_sleep>;
+	interrupts-extended = <&intc GIC_SPI 604 IRQ_TYPE_LEVEL_HIGH>,
+				<&tlmm 41 IRQ_TYPE_EDGE_FALLING>;
+
 	status = "okay";
 
 	bluetooth: bluetooth {
@@ -1345,4 +1350,47 @@ ap_spi_fp: &spi10 {
 			drive-strength = <2>;
 		};
 	};
+
+	qup_uart3_sleep: qup-uart3-sleep {
+		pinmux {
+			pins = "gpio38", "gpio39",
+			       "gpio40", "gpio41";
+			function = "gpio";
+		};
+
+		pinconf-cts {
+			/*
+			 * Configure a pull-down on CTS to match the pull of
+			 * the Bluetooth module.
+			 */
+			pins = "gpio38";
+			bias-pull-down;
+		};
+
+		pinconf-rts {
+			/*
+			 * Configure pull-down on RTS to make sure that the BT SoC can
+			 * wake up the system by sending wakeup bytes during suspend.
+			 */
+			 pins = "gpio39";
+			 bias-pull-down;
+		};
+
+		pinconf-tx {
+			/* Configure pull-up on TX when it isn't actively driven */
+			pins = "gpio40";
+			bias-pull-up;
+		};
+
+		pinconf-rx {
+			/*
+			 * Configure a pull-up on RX. This is needed to avoid
+			 * garbage data when the TX pin of the Bluetooth module is
+			 * in tri-state (module powered off or not driving the
+			 * signal yet).
+			 */
+			pins = "gpio41";
+			bias-pull-up;
+		};
+	};
 };
-- 
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