linux-kernel - [PATCH 2/4] RTC: remove unnecessary device_get() in rtc_device

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Date:	Mon, 20 Jul 2015 16:02:50 -0700
From:	Dmitry Torokhov <dmitry.torokhov@...il.com>
To:	Alessandro Zummo <a.zummo@...ertech.it>,
	Alexandre Belloni <alexandre.belloni@...e-electrons.com>
Cc:	rtc-linux@...glegroups.com, linux-kernel@...r.kernel.org
Subject: [PATCH 2/4] RTC: remove unnecessary device_get() in rtc_device_unregister

Technically the address of rtc->dev can never be NULL, so get_device()
can never fail. Also caller of rtc_device_unregister() supposed to be
the owner of the device and thus have a valid reference. Therefore
call to get_device() is not needed here.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
---
 drivers/rtc/class.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index eb82ec2..de7707f 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -266,19 +266,18 @@ EXPORT_SYMBOL_GPL(rtc_device_register);
  */
 void rtc_device_unregister(struct rtc_device *rtc)
 {
-	if (get_device(&rtc->dev) != NULL) {
-		mutex_lock(&rtc->ops_lock);
-		/* remove innards of this RTC, then disable it, before
-		 * letting any rtc_class_open() users access it again
-		 */
-		rtc_sysfs_del_device(rtc);
-		rtc_dev_del_device(rtc);
-		rtc_proc_del_device(rtc);
-		device_unregister(&rtc->dev);
-		rtc->ops = NULL;
-		mutex_unlock(&rtc->ops_lock);
-		put_device(&rtc->dev);
-	}
+	mutex_lock(&rtc->ops_lock);
+	/*
+	 * Remove innards of this RTC, then disable it, before
+	 * letting any rtc_class_open() users access it again
+	 */
+	rtc_sysfs_del_device(rtc);
+	rtc_dev_del_device(rtc);
+	rtc_proc_del_device(rtc);
+	device_del(&rtc->dev);
+	rtc->ops = NULL;
+	mutex_unlock(&rtc->ops_lock);
+	put_device(&rtc->dev);
 }
 EXPORT_SYMBOL_GPL(rtc_device_unregister);
 
-- 
2.4.3.573.g4eafbef

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