[PATCH] media: ipu-bridge: do not use the CVS device lookup for IVSC
From: Sergey Zagursky
Date: Tue Sep 01 2026 - 15:52:17 EST
Since commit c6b1b34b5090 ("media: pci: intel: Add CVS support for IPU
bridge driver") the internal camera no longer works on laptops where the
sensor sits behind an IVSC, for example a Dell XPS 16 9640 (IPU6,
INTC10CF, ov02c10):
intel-ipu6 0000:00:05.0: Found supported sensor OVTI02C1:00
intel-ipu6 0000:00:05.0: Connected 1 cameras
ivsc_csi intel_vsc-92335fcf-3203-4472-af93-7b4453ac29da: mei-csi probed
without device fwnode!
No sensor subdevice is registered, the media graph has no sensor entity
and userspace finds no camera at all.
ipu_bridge_get_ivsc_csi_dev() first looks for the platform device named
"intel_vsc" and returns its mei-csi child. That device is created by
mei_vsc, which on this machine only appears once the LJCA USB bridge and
its SPI controller have probed, about a second after the IPU6 probe that
runs the bridge:
07:59:29.297 platform INTC10CF:00 created (ACPI scan)
07:59:41 intel-ipu6 probe -> ipu_bridge_init()
07:59:42.391 platform intel_vsc created (mei_vsc)
The commit above added two fallbacks for CVS which match on the ACPI
companion alone. They are reached for every entry of ivsc_acpi_ids[],
IVSC IDs included. The IVSC ACPI device has two physical nodes:
INTC10CF:00/physical_node -> platform/INTC10CF:00 (no driver bound)
INTC10CF:00/physical_node1 -> platform/intel_vsc (mei_vsc)
so bus_find_device_by_acpi_dev(&platform_bus_type, adev) returns the bare
platform device. ipu_bridge_instantiate_ivsc() then attaches the IVSC
software node to that device instead of to the mei-csi client, the bridge
reports success, and the probe is never retried. mei_csi later probes
without a fwnode, the CSI-2 link is never described, and the sensor ACPI
device, which has an honoured _DEP on the IVSC device, is never
enumerated.
Before those fallbacks existed the lookup returned NULL here, the bridge
failed with -ENODEV and the probe was retried once the IVSC device had
shown up.
Restrict the two fallbacks to the CVS IDs. CVS binds a driver to the ACPI
device itself, so matching on the companion is unambiguous there.
Fixes: c6b1b34b5090 ("media: pci: intel: Add CVS support for IPU bridge driver")
Link: https://lore.kernel.org/linux-media/20260901194526.6369-1-gvozdoder@xxxxxxxxx/
Cc: stable@xxxxxxxxxxxxxxx
Assisted-by: Claude Code:claude-opus-5
Signed-off-by: Sergey Zagursky <gvozdoder@xxxxxxxxx>
---
Tested on the affected machine (Dell XPS 16 9640, IPU6 + IVSC + ov02c10) on
top of 7.2.2, where drivers/media/pci/intel/ipu-bridge.c is byte-identical
to v7.2. Without the patch libcamera finds no camera at all; with it:
$ cam -l
1: Internal front camera (\_SB_.PC00.LNK1)
$ cam -c1 --capture=5
202.794954 (30.05 fps) cam0-stream0 seq: 000003 bytesused: 8386560
202.828224 (30.06 fps) cam0-stream0 seq: 000004 bytesused: 8386560
The media graph gains the entities that were missing:
- entity 349: Intel IVSC CSI (2 pads, 2 links, 0 routes)
- entity 368: ov02c10 21-0036 (1 pad, 1 link, 0 routes)
and the restored retry is visible in dmesg:
pci 0000:00:05.0: deferred probe pending: intel-ipu6: IPU6 bridge init failed
intel-ipu6 0000:00:05.0: Found supported sensor OVTI02C1:00
intel-ipu6 0000:00:05.0: Connected 1 cameras
"mei-csi probed without device fwnode!" is gone, ov02c10 binds to
i2c-OVTI02C1:00, and eight v4l-subdev nodes appear.
This patch is against v7.3-rc1. The version tested on 7.2.2 is the same
change without the INTC10FA entry, which 7.2.x does not have. Building
drivers/media/pci/intel/ipu-bridge.c with W=1 produces no new warnings.
Not covered: I have no CVS hardware, so the CVS path is only reasoned
about, not tested, and I have not booted v7.3-rc1 itself.
This patch was produced with the help of an AI coding assistant; see the
Assisted-by tag above and Documentation/process/generated-content.rst. The
bug report this replies to describes what the tool did.
drivers/media/pci/intel/ipu-bridge.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/drivers/media/pci/intel/ipu-bridge.c b/drivers/media/pci/intel/ipu-bridge.c
index 1bb3a3e98d6b..2c3b9efb0b2f 100644
--- a/drivers/media/pci/intel/ipu-bridge.c
+++ b/drivers/media/pci/intel/ipu-bridge.c
@@ -232,6 +232,15 @@ static const struct acpi_device_id ivsc_acpi_ids[] = {
{ "INTC10FA" }, /* NVL */
};
+/* The subset of ivsc_acpi_ids[] which are CVS, rather than IVSC, devices. */
+static const struct acpi_device_id cvs_acpi_ids[] = {
+ { "INTC10DE" }, /* LNL */
+ { "INTC10E0" }, /* ARL */
+ { "INTC10E1" }, /* PTL */
+ { "INTC10FA" }, /* NVL */
+ { }
+};
+
static struct acpi_device *ipu_bridge_get_ivsc_acpi_dev(struct acpi_device *adev)
{
unsigned int i;
@@ -283,6 +292,17 @@ static struct device *ipu_bridge_get_ivsc_csi_dev(struct acpi_device *adev)
return csi_dev;
}
+ /*
+ * The lookups below match on the ACPI companion alone. That is fine for
+ * CVS, which binds a driver to that very device, but not for IVSC: there
+ * the ACPI device also has a driverless platform device, which would be
+ * returned instead of the mei-csi client. Return NULL for IVSC so that
+ * the caller fails and the probe is retried once the IVSC device shows
+ * up.
+ */
+ if (acpi_match_device_ids(adev, cvs_acpi_ids))
+ return NULL;
+
/* Try to locate CVS device on the I2C bus */
csi_dev = bus_find_device_by_acpi_dev(&i2c_bus_type, adev);
if (csi_dev)
--
2.55.0