[RFC PATCH] arm64: dts: qcom: add device tree for DB845c working in dual DSI mode

[Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>]

While we are testing the DB845c working in dual DSI mode (which is
required for the 4k support), create a separate device tree using this
configuration.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---

Dependencies to be able to verify the 4k@30 mode:
[1] https://lore.kernel.org/linux-arm-msm/20221229191856.3508092-1-dmitry.baryshkov@xxxxxxxxxx/
[2] https://lore.kernel.org/dri-devel/20230118081658.2198520-1-dmitry.baryshkov@xxxxxxxxxx/

---
 arch/arm64/boot/dts/qcom/Makefile             |  1 +
 .../boot/dts/qcom/sdm845-db845c-dual-dsi.dts  | 48 +++++++++++++++++++
 2 files changed, 49 insertions(+)
 create mode 100644 arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts

diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
index 3e79496292e7..dc55c3b989a4 100644
--- a/arch/arm64/boot/dts/qcom/Makefile
+++ b/arch/arm64/boot/dts/qcom/Makefile
@@ -139,6 +139,7 @@ dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-cheza-r1.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-cheza-r2.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-cheza-r3.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-db845c.dtb
+dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-db845c-dual-dsi.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-db845c-navigation-mezzanine.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-lg-judyln.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdm845-lg-judyp.dtb
diff --git a/arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts b/arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts
new file mode 100644
index 000000000000..4a366dedc841
--- /dev/null
+++ b/arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2023, Linaro Ltd.
+ */
+
+#include "sdm845-db845c.dts"
+
+&dsi0 {
+	qcom,dual-dsi-mode;
+	qcom,master-dsi;
+};
+
+&dsi1 {
+	vdda-supply = <&vreg_l26a_1p2>;
+
+	qcom,dual-dsi-mode;
+
+	/* DSI1 is slave, so use DSI0 clocks */
+	assigned-clock-parents = <&dsi0_phy 0>, <&dsi0_phy 1>;
+
+	status = "okay";
+
+	ports {
+		port@1 {
+			endpoint {
+				remote-endpoint = <&lt9611_b>;
+				data-lanes = <0 1 2 3>;
+			};
+		};
+	};
+};
+
+&dsi1_phy {
+	vdds-supply = <&vreg_l1a_0p875>;
+	status = "okay";
+};
+
+&lt9611_codec {
+	ports {
+		port@1 {
+			reg = <1>;
+
+			lt9611_b: endpoint {
+				remote-endpoint = <&dsi1_out>;
+			};
+		};
+	};
+};
-- 
2.39.0