[PATCH v1] media: i2c: alvium: Fix controls for WB/AWB

From: Martin Hecht

Date: Tue May 05 2026 - 10:26:15 EST


With that patch the controls for red-balance and blue-balance were created
only if the particular camera supports that. Otherwise the pointers on
the control variable are initialized with NULL to prevent side effects for
clustering with AWB control.

Fixes: 0a7af872915e ("media: i2c: Add support for alvium camera")
Signed-off-by: Martin Hecht <mhecht73@xxxxxxxxx>
---
drivers/media/i2c/alvium-csi2.c | 37 ++++++++++++++++++++-------------
1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/drivers/media/i2c/alvium-csi2.c b/drivers/media/i2c/alvium-csi2.c
index b62b45a4f2fc..4c6934e9e177 100644
--- a/drivers/media/i2c/alvium-csi2.c
+++ b/drivers/media/i2c/alvium-csi2.c
@@ -2108,26 +2108,33 @@ static int alvium_ctrl_init(struct alvium_dev *alvium)
0, 0, &alvium->link_freq);
ctrls->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;

+ if (alvium->avail_ft.whiteb) {
+ ctrls->blue_balance = v4l2_ctrl_new_std(hdl, ops,
+ V4L2_CID_BLUE_BALANCE,
+ alvium->min_bbalance,
+ alvium->max_bbalance,
+ alvium->inc_bbalance,
+ alvium->dft_bbalance);
+ ctrls->red_balance = v4l2_ctrl_new_std(hdl, ops,
+ V4L2_CID_RED_BALANCE,
+ alvium->min_rbalance,
+ alvium->max_rbalance,
+ alvium->inc_rbalance,
+ alvium->dft_rbalance);
+ } else {
+ /* set to NULL for v4l2_ctrl_auto_cluster if not existing */
+ ctrls->blue_balance = NULL;
+ ctrls->red_balance = NULL;
+ }
+
/* Auto/manual white balance */
if (alvium->avail_ft.auto_whiteb) {
ctrls->auto_wb = v4l2_ctrl_new_std(hdl, ops,
V4L2_CID_AUTO_WHITE_BALANCE,
0, 1, 1, 1);
- v4l2_ctrl_auto_cluster(3, &ctrls->auto_wb, 0, false);
- }
-
- ctrls->blue_balance = v4l2_ctrl_new_std(hdl, ops,
- V4L2_CID_BLUE_BALANCE,
- alvium->min_bbalance,
- alvium->max_bbalance,
- alvium->inc_bbalance,
- alvium->dft_bbalance);
- ctrls->red_balance = v4l2_ctrl_new_std(hdl, ops,
- V4L2_CID_RED_BALANCE,
- alvium->min_rbalance,
- alvium->max_rbalance,
- alvium->inc_rbalance,
- alvium->dft_rbalance);
+
+ v4l2_ctrl_auto_cluster(3, &ctrls->auto_wb, 0, true);
+ }

/* Auto/manual exposure */
if (alvium->avail_ft.auto_exp) {
--
2.43.0