[PATCH 1/2] media: ipu6: isys: use the port B 2-lane PHY settings for 1-lane sensors

[Dan Person]

On the Lenovo ThinkPad X1 Carbon Gen 11 (Raptor Lake, IPU6EP) the IR
camera, an OmniVision OV9234 (ACPI OVTI9234), is a single-lane CSI-2
sensor on driver port 0, which ipu6_isys_driver_port_to_phy_port() maps
to MCD PHY port B. With x1_port1_config_regs the receiver accepts the
stream - firmware open/start are acknowledged, the PHY reports ready and
the CSI-2 error status stays clear - but no frame is ever written and
every capture ends in a buffer timeout and "stream stop time out".

The Windows IPU6 driver for this machine embeds the same MCD PHY register
tables. It has no 1-lane table for port B; a 1-lane sensor there is
programmed with the 2-lane port B set (PPI 3/4/5). The Linux 1-lane port B
table also writes 0x5d060100 to register 0xaa8, a value that appears in
no Windows table and breaks the pattern of every other data-lane entry.

Use x2_port1_config_regs for 1-lane sensors on port B and drop the
now-unused x1_port1_config_regs. With this change the OV9234 streams
Y10 644x364 at 30 fps, alongside the 2-lane OV2740 on the other port.

Tested on Linux 6.14 and 7.0 with an out-of-tree OV9234 driver.

Signed-off-by: Dan Person <it@xxxxxxxxxxxxxx>
---
 .../media/pci/intel/ipu6/ipu6-isys-mcd-phy.c  | 31 ++++---------------
 1 file changed, 6 insertions(+), 25 deletions(-)

diff --git a/drivers/media/pci/intel/ipu6/ipu6-isys-mcd-phy.c
b/drivers/media/pci/intel/ipu6/ipu6-isys-mcd-phy.c
index 71aa500..cae4dc7 100644
--- a/drivers/media/pci/intel/ipu6/ipu6-isys-mcd-phy.c
+++ b/drivers/media/pci/intel/ipu6/ipu6-isys-mcd-phy.c
@@ -150,30 +150,6 @@ static const struct phy_reg x1_port0_config_regs[] = {
 	{0x00000000, 0x00000000}
 };

-static const struct phy_reg x1_port1_config_regs[] = {
-	{0x00000c94, 0xc80060fa},
-	{0x00000c80, 0xcf47abea},
-	{0x00000c90, 0x10a0840b},
-	{0x00000ca8, 0xdf04010a},
-	{0x00000d00, 0x57050060},
-	{0x00000d10, 0x0030001c},
-	{0x00000d38, 0x5f004444},
-	{0x00000d3c, 0x78464204},
-	{0x00000d48, 0x7821f940},
-	{0x00000d4c, 0xb2000433},
-	{0x00000a94, 0xc91030fa},
-	{0x00000a80, 0x5a166ed0},
-	{0x00000a90, 0x10a0540b},
-	{0x00000aa8, 0x5d060100},
-	{0x00000b00, 0xef053460},
-	{0x00000b10, 0xa030101c},
-	{0x00000b38, 0xdf808444},
-	{0x00000b3c, 0xc8422204},
-	{0x00000b40, 0x0180088c},
-	{0x00000b74, 0x00000000},
-	{0x00000000, 0x00000000}
-};
-
 static const struct phy_reg x1_port2_config_regs[] = {
 	{0x00001294, 0x28f000fa},
 	{0x00001280, 0x08130cea},
@@ -475,7 +451,12 @@ static const struct phy_reg x4_port3_config_regs[] = {

 static const struct phy_reg *x1_config_regs[4] = {
 	x1_port0_config_regs,
-	x1_port1_config_regs,
+	/*
+	 * A 1-lane sensor on PHY port B does not stream with a dedicated
+	 * 1-lane table; program it with the 2-lane port B set, as the
+	 * Windows driver does.
+	 */
+	x2_port1_config_regs,
 	x1_port2_config_regs,
 	x1_port3_config_regs
 };
-- 
2.53.0