[PATCH] hwrng: cctrng - Fix an error handling path in cctrng_probe

[Christophe JAILLET]

If an error occurs after a successful cc_trng_pm_init() call, it must be
undone by a corresponding cc_trng_pm_fini() call.

The commit in Fixes has erroneously updated the error handling path if
cc_trng_pm_get() fails.

Fixes: 8bcd96893848 ("hwrng: cctrng - let devres enable the clock")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
Compile tested only.

This patch also undo the clean-up done by commit a7ea3d63e897 ("hwrng:
cctrng - simplify cctrng_probe()"). Keeping an error path makes sense with
2 users. But if preferred, the missing cc_trng_pm_fini() could also be
added after the test for errors in cc_trng_pm_get().
---
 drivers/char/hw_random/cctrng.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/char/hw_random/cctrng.c b/drivers/char/hw_random/cctrng.c
index 03401ee59a8e..608b3321c05a 100644
--- a/drivers/char/hw_random/cctrng.c
+++ b/drivers/char/hw_random/cctrng.c
@@ -524,8 +524,10 @@ static int cctrng_probe(struct platform_device *pdev)
 
 	/* increment device's usage counter */
 	rc = cc_trng_pm_get(dev);
-	if (rc)
-		return dev_err_probe(dev, rc, "cc_trng_pm_get returned %x\n", rc);
+	if (rc) {
+		dev_err_probe(dev, rc, "cc_trng_pm_get returned %x\n", rc);
+		goto post_pm_err;
+	}
 
 	/* set pending_hw to verify that HW won't be triggered from read */
 	atomic_set(&drvdata->pending_hw, 1);
@@ -534,8 +536,7 @@ static int cctrng_probe(struct platform_device *pdev)
 	rc = devm_hwrng_register(dev, &drvdata->rng);
 	if (rc) {
 		dev_err(dev, "Could not register hwrng device.\n");
-		cc_trng_pm_fini(drvdata);
-		return rc;
+		goto post_pm_err;
 	}
 
 	/* trigger HW to start generate data */
@@ -548,6 +549,11 @@ static int cctrng_probe(struct platform_device *pdev)
 	dev_info(dev, "ARM cctrng device initialized\n");
 
 	return 0;
+
+post_pm_err:
+	cc_trng_pm_fini(drvdata);
+
+	return rc;
 }
 
 static void cctrng_remove(struct platform_device *pdev)
-- 
2.56.0