[PATCH v3 1/3] driver core: Make parameter check consistent for API cluster device_(for_each|find)_child()

[Zijun Hu <zijun_hu@icloud.com>]

From: Zijun Hu <quic_zijuhu@quicinc.com>

The following API cluster takes the same type parameter list, but do not
have consistent parameter check as shown below.

device_for_each_child(struct device *parent, ...)  // check (!parent->p)
device_for_each_child_reverse(struct device *parent, ...) // same as above
device_find_child(struct device *parent, ...)      // check (!parent)

Fixed by using consistent check (!parent || !parent->p) which covers
both existing checks for the cluster.

Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
---
 drivers/base/core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 4bc8b88d697e..c066b581ce34 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -3993,7 +3993,7 @@ int device_for_each_child(struct device *parent, void *data,
 	struct device *child;
 	int error = 0;
 
-	if (!parent->p)
+	if (!parent || !parent->p)
 		return 0;
 
 	klist_iter_init(&parent->p->klist_children, &i);
@@ -4023,7 +4023,7 @@ int device_for_each_child_reverse(struct device *parent, void *data,
 	struct device *child;
 	int error = 0;
 
-	if (!parent->p)
+	if (!parent || !parent->p)
 		return 0;
 
 	klist_iter_init(&parent->p->klist_children, &i);
@@ -4057,7 +4057,7 @@ struct device *device_find_child(struct device *parent, void *data,
 	struct klist_iter i;
 	struct device *child;
 
-	if (!parent)
+	if (!parent || !parent->p)
 		return NULL;
 
 	klist_iter_init(&parent->p->klist_children, &i);

-- 
2.34.1