queue-6.6/drm-amdgpu-check-thunderbolt-before-switcheroo-registration.patch

From 8587d48d694da5aca580f92461658ec14470592b Mon Sep 17 00:00:00 2001
From: Yang Wang <kevinyang.wang@amd.com>
Date: Wed, 12 Aug 2026 11:08:40 +0800
Subject: drm/amdgpu: check thunderbolt before switcheroo registration

From: Yang Wang <kevinyang.wang@amd.com>

commit 8587d48d694da5aca580f92461658ec14470592b upstream.

Introduce a helper to consolidate the vga_switcheroo registration condition
used by the init and fini paths.

Keep the explicit pci_is_thunderbolt_attached() check, as dev_is_removable()
does not provide equivalent coverage for Thunderbolt-attached GPUs.
This ensures such devices remain excluded from switcheroo registration while
preserving the existing PX and Apple gmux handling.

Cc: stable@vger.kernel.org
Signed-off-by: Yang Wang <kevinyang.wang@amd.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3586,6 +3586,14 @@ static void amdgpu_device_set_mcbp(struc
 		DRM_INFO("MCBP is enabled\n");
 }
 
+static bool
+amdgpu_device_should_register_switcheroo(struct amdgpu_device *adev, bool px)
+{
+	return !pci_is_thunderbolt_attached(adev->pdev) &&
+	       (px || (!dev_is_removable(&adev->pdev->dev) &&
+		       apple_gmux_detect(NULL, NULL)));
+}
+
 /**
  * amdgpu_device_init - initialize the driver
  *
@@ -4002,8 +4010,7 @@ fence_driver_init:
 
 	px = amdgpu_device_supports_px(ddev);
 
-	if (px || (!dev_is_removable(&adev->pdev->dev) &&
-				apple_gmux_detect(NULL, NULL)))
+	if (amdgpu_device_should_register_switcheroo(adev, px))
 		vga_switcheroo_register_client(adev->pdev,
 					       &amdgpu_switcheroo_ops, px);
 
@@ -4162,8 +4169,7 @@ void amdgpu_device_fini_sw(struct amdgpu
 
 	px = amdgpu_device_supports_px(adev_to_drm(adev));
 
-	if (px || (!dev_is_removable(&adev->pdev->dev) &&
-				apple_gmux_detect(NULL, NULL)))
+	if (amdgpu_device_should_register_switcheroo(adev, px))
 		vga_switcheroo_unregister_client(adev->pdev);
 
 	if (px)