[PATCH v5 06/16] media: sony-starvis2: Allow runtime control of link frequency
From: Dave Stevenson
Date: Mon Oct 19 2026 - 12:37:21 EST
DT allows configuration of multiple link frequencies.
V4L2_CID_LINK_FREQ allows read write control.
Join these up so that link frequency can be configured at run time,
as long as the sensor isn't streaming.
Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
---
drivers/media/i2c/sony-starvis2.c | 82 +++++++++++++++++++++++++++------------
1 file changed, 58 insertions(+), 24 deletions(-)
diff --git a/drivers/media/i2c/sony-starvis2.c b/drivers/media/i2c/sony-starvis2.c
index b0b1716a86e2..56fa2d5ea3fe 100644
--- a/drivers/media/i2c/sony-starvis2.c
+++ b/drivers/media/i2c/sony-starvis2.c
@@ -725,6 +725,7 @@ struct starvis2 {
struct v4l2_ctrl *exposure;
struct v4l2_ctrl *vblank;
struct v4l2_ctrl *hblank;
+ struct v4l2_ctrl *link_freq;
/* Track VMAX for exposure updates */
u32 vmax;
@@ -755,6 +756,7 @@ static int starvis2_set_ctrl(struct v4l2_ctrl *ctrl)
struct starvis2 *starvis2 = container_of_const(ctrl->handler, struct
starvis2, ctrl_handler);
struct i2c_client *client = v4l2_get_subdevdata(&starvis2->sd);
+ const struct starvis2_variant *variant = starvis2->variant;
const struct v4l2_mbus_framefmt *format;
struct v4l2_subdev_state *state;
int ret = 0;
@@ -778,6 +780,25 @@ static int starvis2_set_ctrl(struct v4l2_ctrl *ctrl)
return ret;
}
+ if (ctrl->id == V4L2_CID_LINK_FREQ) {
+ u32 hmax = variant->hmax_min_link_freq[ctrl->val];
+ s32 hblank;
+
+ if (starvis2->lane_mode == STARVIS2_LANEMODE_4L)
+ hmax = max(hmax >> 1, variant->hmax_min_pixel_array);
+
+ hblank = hmax * variant->pix_per_clk -
+ variant->active_area.width;
+
+ ret = __v4l2_ctrl_modify_range(starvis2->hblank,
+ hblank,
+ starvis2->hblank->maximum,
+ starvis2->hblank->step,
+ hblank);
+ if (ret)
+ return ret;
+ }
+
/*
* Only apply control values when device is powered on (RPM ACTIVE)
* and streaming (usage count != 0)
@@ -824,6 +845,12 @@ static int starvis2_set_ctrl(struct v4l2_ctrl *ctrl)
cci_write(starvis2->cci, STARVIS2_REG_WINMODEV, ctrl->val,
&ret);
break;
+ case V4L2_CID_LINK_FREQ:
+ /* The STARVIS2_LINK_FREQ_ enums match up with the register */
+ cci_write(starvis2->cci, STARVIS2_REG_DATARATE_SEL, ctrl->val,
+ &ret);
+ break;
+
default:
dev_warn(&client->dev,
"ctrl(id:0x%x,val:0x%x) is not handled\n",
@@ -938,9 +965,6 @@ static int starvis2_write_common(struct starvis2 *starvis2)
cci_write(starvis2->cci, STARVIS2_REG_INCK_SEL, starvis2->inck_sel_val,
&ret);
- cci_write(starvis2->cci, STARVIS2_REG_DATARATE_SEL,
- __fls(starvis2->link_freq_bitmap),
- &ret);
cci_write(starvis2->cci, STARVIS2_REG_LANEMODE, starvis2->lane_mode,
&ret);
@@ -1019,6 +1043,7 @@ static int starvis2_enable_streams(struct v4l2_subdev *sd,
goto err_rpm_put;
}
+ __v4l2_ctrl_grab(starvis2->link_freq, true);
return 0;
err_rpm_put:
@@ -1043,6 +1068,8 @@ static int starvis2_disable_streams(struct v4l2_subdev *sd,
if (ret)
dev_err(&client->dev, "%s failed to stop stream\n", __func__);
+ __v4l2_ctrl_grab(starvis2->link_freq, false);
+
pm_runtime_put(&client->dev);
return ret;
@@ -1209,7 +1236,6 @@ static int starvis2_init_controls(struct starvis2 *starvis2)
struct i2c_client *client = v4l2_get_subdevdata(&starvis2->sd);
const struct starvis2_variant *variant = starvis2->variant;
struct v4l2_fwnode_device_properties props;
- struct v4l2_ctrl *link_freq;
s32 hblank, max_hblank, vblank, max_vblank;
u32 hmax;
int ret;
@@ -1225,25 +1251,26 @@ static int starvis2_init_controls(struct starvis2 *starvis2)
starvis2->vmax = starvis2->variant->vmax_default;
- hmax = variant->hmax_min_link_freq[__fls(starvis2->link_freq_bitmap)];
- if (starvis2->lane_mode == STARVIS2_LANEMODE_4L)
- hmax = max(hmax >> 1, variant->hmax_min_pixel_array);
-
/* PIXEL_RATE is fixed and read-only */
v4l2_ctrl_new_std(ctrl_hdlr, &starvis2_ctrl_ops, V4L2_CID_PIXEL_RATE,
starvis2->variant->pixel_rate,
starvis2->variant->pixel_rate, 1,
starvis2->variant->pixel_rate);
- /* LINK_FREQ is also read only */
- link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr, &starvis2_ctrl_ops,
- V4L2_CID_LINK_FREQ,
- ARRAY_SIZE(link_freqs) - 1,
- __ffs(starvis2->link_freq_bitmap),
- link_freqs);
-
- if (link_freq)
- link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+ starvis2->link_freq =
+ v4l2_ctrl_new_int_menu(ctrl_hdlr, &starvis2_ctrl_ops,
+ V4L2_CID_LINK_FREQ,
+ __fls(starvis2->link_freq_bitmap),
+ __ffs(starvis2->link_freq_bitmap),
+ link_freqs);
+ if (!starvis2->link_freq)
+ goto err_free_handler;
+
+ v4l2_ctrl_modify_range(starvis2->link_freq,
+ __ffs(starvis2->link_freq_bitmap),
+ __fls(starvis2->link_freq_bitmap),
+ ~(starvis2->link_freq_bitmap),
+ __ffs(starvis2->link_freq_bitmap));
vblank = starvis2->vmax - starvis2->variant->active_area.height;
max_vblank = STARVIS2_VMAX_MAX - starvis2->variant->active_area.height;
@@ -1251,6 +1278,10 @@ static int starvis2_init_controls(struct starvis2 *starvis2)
V4L2_CID_VBLANK, vblank, max_vblank,
2, vblank);
+ hmax = variant->hmax_min_link_freq[starvis2->link_freq->val];
+ if (starvis2->lane_mode == STARVIS2_LANEMODE_4L)
+ hmax = max(hmax >> 1, variant->hmax_min_pixel_array);
+
hblank = hmax * starvis2->variant->pix_per_clk -
starvis2->variant->active_area.width;
max_hblank = STARVIS2_HMAX_MAX * starvis2->variant->pix_per_clk -
@@ -1285,17 +1316,20 @@ static int starvis2_init_controls(struct starvis2 *starvis2)
v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &starvis2_ctrl_ops, &props);
- if (ctrl_hdlr->error) {
- ret = ctrl_hdlr->error;
- dev_err(&client->dev, "%s control init failed (%d)\n",
- __func__, ret);
- v4l2_ctrl_handler_free(ctrl_hdlr);
- return ret;
- }
+ if (ctrl_hdlr->error)
+ goto err_free_handler;
starvis2->sd.ctrl_handler = ctrl_hdlr;
return 0;
+
+err_free_handler:
+ ret = ctrl_hdlr->error;
+ dev_err(&client->dev, "%s control init failed (%d)\n",
+ __func__, ret);
+ v4l2_ctrl_handler_free(ctrl_hdlr);
+
+ return ret;
}
static int starvis2_check_hwcfg(struct device *dev, struct starvis2 *starvis2)
--
2.34.1