[PATCH 08/12] drm/vboxvideo: Use devm aperture helpers for sysfb restore on probe failure

[Zack Rusin <zack.rusin@broadcom.com>]

Use devm_aperture_remove_conflicting_pci_devices() instead of the
non-devm variant to automatically restore the system framebuffer
(efifb/simpledrm) if the driver's probe fails after removing the
firmware framebuffer.

Call devm_aperture_remove_conflicting_pci_devices_done() after
successful probe to cancel the automatic restore, as the driver
is now responsible for display output.

This ensures users don't lose display output if the vboxvideo driver
fails to probe after removing the firmware framebuffer.

Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Cc: Hans de Goede <hansg@kernel.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/vboxvideo/vbox_drv.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vboxvideo/vbox_drv.c b/drivers/gpu/drm/vboxvideo/vbox_drv.c
index bb861f0a0a31..569fd7b60115 100644
--- a/drivers/gpu/drm/vboxvideo/vbox_drv.c
+++ b/drivers/gpu/drm/vboxvideo/vbox_drv.c
@@ -46,7 +46,12 @@ static int vbox_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (!vbox_check_supported(VBE_DISPI_ID_HGSMI))
 		return -ENODEV;
 
-	ret = aperture_remove_conflicting_pci_devices(pdev, driver.name);
+	/*
+	 * Use devm variant to automatically restore sysfb if probe fails.
+	 * This ensures the user doesn't lose display if our probe fails
+	 * after removing the firmware framebuffer (efifb/simpledrm).
+	 */
+	ret = devm_aperture_remove_conflicting_pci_devices(pdev, driver.name);
 	if (ret)
 		return ret;
 
@@ -84,6 +89,12 @@ static int vbox_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	drm_client_setup(&vbox->ddev, NULL);
 
+	/*
+	 * Probe succeeded - cancel the automatic sysfb restore action.
+	 * We're now responsible for display output.
+	 */
+	devm_aperture_remove_conflicting_pci_devices_done(pdev);
+
 	return 0;
 
 err_irq_fini:
-- 
2.48.1