openwrt/target/linux/bcm27xx/patches-6.6/950-0406-media-dw9807-vcm-Smooth-the-first-user-movement-of-t.patch

From 90ea312b19786689637a4d75f6e405f41107bbca Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Tue, 3 Jan 2023 16:53:37 +0000
Subject: [PATCH 0406/1085] media: dw9807-vcm: Smooth the first user movement
 of the lens

The power up/down sequence is already ramped. Extend this to
the first user movement as well, as this will generally avoid
the "tick" noises due to rapid movements and overshooting.
Subsequent movements are generally smaller and so don't cause
issues.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/media/i2c/dw9807-vcm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/media/i2c/dw9807-vcm.c
+++ b/drivers/media/i2c/dw9807-vcm.c
@@ -62,6 +62,7 @@ struct dw9807_device {
 	u16 idle_pos;
 	struct regulator *vdd;
 	struct notifier_block notifier;
+	bool first;
 };
 
 static inline struct dw9807_device *sd_to_dw9807_vcm(
@@ -176,6 +177,8 @@ static int dw9807_active(struct dw9807_d
 		return ret;
 	}
 
+	dw9807_dev->first = true;
+
 	return dw9807_ramp(client, dw9807_dev->idle_pos, dw9807_dev->current_val);
 }
 
@@ -230,9 +233,11 @@ static int dw9807_set_ctrl(struct v4l2_c
 
 	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) {
 		struct i2c_client *client = v4l2_get_subdevdata(&dev_vcm->sd);
+		int start = (dev_vcm->first) ? dev_vcm->current_val : ctrl->val;
 
+		dev_vcm->first = false;
 		dev_vcm->current_val = ctrl->val;
-		return dw9807_ramp(client, ctrl->val, ctrl->val);
+		return dw9807_ramp(client, start, ctrl->val);
 	}
 
 	return -EINVAL;