[PATCH] ACPI: video: Don't allow MFD devices to probe

["Mario Limonciello (AMD)" <superm1@kernel.org>]

After ACPI video was converted into a platform device in
commit 02c057ddefef5 ("ACPI: video: Convert the driver to a platform one")
other devices that are MFD children of LNXVIDEO are being probed.
This isn't intended.

During probe detect MFD cells and reject them.

Fixes: 02c057ddefef5 ("ACPI: video: Convert the driver to a platform one")
Reported-by: Pratap Nirujogi <pnirujog@amd.com>
Closes: https://lore.kernel.org/regressions/007e3390-6b2b-457e-83c7-c794c5952018@amd.com/
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
---
 drivers/acpi/acpi_video.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 3fa28f1abca38..2cb526775ac47 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -14,6 +14,7 @@
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/list.h>
+#include <linux/mfd/core.h>
 #include <linux/mutex.h>
 #include <linux/input.h>
 #include <linux/backlight.h>
@@ -1988,6 +1989,9 @@ static int acpi_video_bus_probe(struct platform_device *pdev)
 	int error;
 	acpi_status status;
 
+	if (mfd_get_cell(pdev))
+		return -ENODEV;
+
 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
 				acpi_dev_parent(device)->handle, 1,
 				acpi_video_bus_match, NULL,
-- 
2.43.0