From 51ffd9e0114f1ffa48c6773035ee3448bf4e86cc Mon Sep 17 00:00:00 2001
From: Beyley Cardellio <ep1cm1n10n123@gmail.com>
Date: Wed, 5 Nov 2025 18:50:14 -0800
Subject: [PATCH] xrt: Switch scannout duration to int64_t

Part-of: <https://gitlab.freedesktop.org/monado/monado/-/merge_requests/2616>
---
 src/xrt/compositor/main/comp_renderer.c | 2 +-
 src/xrt/drivers/steamvr_lh/device.cpp   | 4 ++--
 src/xrt/drivers/steamvr_lh/device.hpp   | 2 +-
 src/xrt/include/xrt/xrt_device.h        | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/xrt/compositor/main/comp_renderer.c b/src/xrt/compositor/main/comp_renderer.c
index 2c83d865d..6cbb17813 100644
--- a/src/xrt/compositor/main/comp_renderer.c
+++ b/src/xrt/compositor/main/comp_renderer.c
@@ -259,7 +259,7 @@ calc_pose_data(struct comp_renderer *r,
 	struct xrt_fov xdev_fovs[XRT_MAX_VIEWS] = XRT_STRUCT_INIT;
 	struct xrt_pose xdev_poses[2][XRT_MAX_VIEWS] = XRT_STRUCT_INIT;
 
-	uint64_t scanout_time_ns = 0;
+	int64_t scanout_time_ns = 0;
 	if (r->c->xdev->hmd->screens[0].scanout_direction == XRT_SCANOUT_DIRECTION_TOP_TO_BOTTOM) {
 		scanout_time_ns = r->c->xdev->hmd->screens[0].scanout_time_ns;
 	} else if (r->c->xdev->hmd->screens[0].scanout_direction != XRT_SCANOUT_DIRECTION_NONE) {
diff --git a/src/xrt/drivers/steamvr_lh/device.cpp b/src/xrt/drivers/steamvr_lh/device.cpp
index 4585e13c7..cf2c496ae 100644
--- a/src/xrt/drivers/steamvr_lh/device.cpp
+++ b/src/xrt/drivers/steamvr_lh/device.cpp
@@ -868,7 +868,7 @@ HmdDevice::set_nominal_frame_interval(uint64_t interval_ns)
 }
 
 void
-HmdDevice::set_scanout_type(xrt_scanout_direction direction, uint64_t time_ns)
+HmdDevice::set_scanout_type(xrt_scanout_direction direction, int64_t time_ns)
 {
 	auto set = [this, direction, time_ns] {
 		hmd_parts->base.screens[0].scanout_direction = direction;
@@ -1047,7 +1047,7 @@ HmdDevice::handle_property_write(const vr::PropertyWrite_t &prop)
 	case vr::Prop_DisplayFrequency_Float: {
 		assert(prop.unBufferSize == sizeof(float));
 		float freq = *static_cast<float *>(prop.pvBuffer);
-		uint64_t interval_ns = (1.f / freq) * 1e9f;
+		int64_t interval_ns = (1.f / freq) * 1e9f;
 		set_nominal_frame_interval(interval_ns);
 		if (variant == VIVE_VARIANT_PRO) {
 			set_scanout_type(XRT_SCANOUT_DIRECTION_TOP_TO_BOTTOM, interval_ns * 1600.0 / 1624.0);
diff --git a/src/xrt/drivers/steamvr_lh/device.hpp b/src/xrt/drivers/steamvr_lh/device.hpp
index 75f3a21d5..ad15e226e 100644
--- a/src/xrt/drivers/steamvr_lh/device.hpp
+++ b/src/xrt/drivers/steamvr_lh/device.hpp
@@ -211,7 +211,7 @@ private:
 	set_nominal_frame_interval(uint64_t interval_ns);
 
 	void
-	set_scanout_type(enum xrt_scanout_direction direction, uint64_t time_ns);
+	set_scanout_type(enum xrt_scanout_direction direction, int64_t time_ns);
 
 	std::condition_variable hmd_parts_cv;
 	std::mutex hmd_parts_mut;
diff --git a/src/xrt/include/xrt/xrt_device.h b/src/xrt/include/xrt/xrt_device.h
index 47d9ce487..d4e6bfcc1 100644
--- a/src/xrt/include/xrt/xrt_device.h
+++ b/src/xrt/include/xrt/xrt_device.h
@@ -103,7 +103,7 @@ struct xrt_hmd_parts
 		//! Nominal frame interval
 		uint64_t nominal_frame_interval_ns;
 		enum xrt_scanout_direction scanout_direction;
-		uint64_t scanout_time_ns;
+		int64_t scanout_time_ns;
 	} screens[1];
 
 	/*!