[PATCH 3/9] media: camss: csid: unwind the power-on path through a single error label

[Qianhui Xu]

csid_set_power() repeats the same cleanup sequence in every error branch
and gets it wrong in the first one: when pm_runtime_resume_and_get()
fails, the parent device reference taken by parent_dev_ops->get() is
never dropped, so a failing power-on leaks it and the matching VFE stays
powered.

Replace the four open-coded unwind blocks with gotos to a shared label
chain and route the pm_runtime failure through the parent put as well.
No functional change on the success path.

Signed-off-by: Qianhui Xu <xiaqinghuan@xxxxxxxxxxxxxxxx>
---
 .../media/platform/qcom/camss/camss-csid.c    | 45 +++++++++----------
 1 file changed, 20 insertions(+), 25 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-csid.c b/drivers/media/platform/qcom/camss/camss-csid.c
index 48459b46a..592c1dfc9 100644
--- a/drivers/media/platform/qcom/camss/camss-csid.c
+++ b/drivers/media/platform/qcom/camss/camss-csid.c
@@ -696,44 +696,28 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 
 		ret = pm_runtime_resume_and_get(dev);
 		if (ret < 0)
-			return ret;
+			goto put_parent;
 
 		ret = regulator_bulk_enable(csid->num_supplies,
 					    csid->supplies);
-		if (ret < 0) {
-			pm_runtime_put_sync(dev);
-			return ret;
-		}
+		if (ret < 0)
+			goto put_pm;
 
 		ret = csid_set_clock_rates(csid);
-		if (ret < 0) {
-			regulator_bulk_disable(csid->num_supplies,
-					       csid->supplies);
-			pm_runtime_put_sync(dev);
-			return ret;
-		}
+		if (ret < 0)
+			goto disable_regulators;
 
 		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
-		if (ret < 0) {
-			regulator_bulk_disable(csid->num_supplies,
-					       csid->supplies);
-			pm_runtime_put_sync(dev);
-			return ret;
-		}
+		if (ret < 0)
+			goto disable_regulators;
 
 		csid->phy.need_vc_update = true;
 
 		enable_irq(csid->irq);
 
 		ret = csid->res->hw_ops->reset(csid);
-		if (ret < 0) {
-			disable_irq(csid->irq);
-			camss_disable_clocks(csid->nclocks, csid->clock);
-			regulator_bulk_disable(csid->num_supplies,
-					       csid->supplies);
-			pm_runtime_put_sync(dev);
-			return ret;
-		}
+		if (ret < 0)
+			goto disable_clocks;
 
 		csid->res->hw_ops->hw_version(csid);
 	} else {
@@ -746,6 +730,17 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
 	}
 
 	return ret;
+
+disable_clocks:
+	disable_irq(csid->irq);
+	camss_disable_clocks(csid->nclocks, csid->clock);
+disable_regulators:
+	regulator_bulk_disable(csid->num_supplies, csid->supplies);
+put_pm:
+	pm_runtime_put_sync(dev);
+put_parent:
+	csid->res->parent_dev_ops->put(camss, csid->id);
+	return ret;
 }
 
 /*