[PATCH 01/27] driver core: Constify driver API device_find_child()

[Zijun Hu <zijun_hu@icloud.com>]

From: Zijun Hu <quic_zijuhu@quicinc.com>

Constify the following driver API:
struct device *device_find_child(struct device *dev, void *data,
		int (*match)(struct device *dev, void *data));
to
struct device *device_find_child(struct device *dev, const void *data,
                                 device_match_t match);
typedef int (*device_match_t)(struct device *dev, const void *data);
Since it should not modify caller's match data @*data.

Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
---
 drivers/base/core.c    | 11 +++--------
 include/linux/device.h |  4 ++--
 2 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 3f3ebdb5aa0b..f152e0f8fb03 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -4062,8 +4062,8 @@ EXPORT_SYMBOL_GPL(device_for_each_child_reverse);
  *
  * NOTE: you will need to drop the reference with put_device() after use.
  */
-struct device *device_find_child(struct device *parent, void *data,
-				 int (*match)(struct device *dev, void *data))
+struct device *device_find_child(struct device *parent, const void *data,
+				 device_match_t match)
 {
 	struct klist_iter i;
 	struct device *child;
@@ -4108,11 +4108,6 @@ struct device *device_find_child_by_name(struct device *parent,
 }
 EXPORT_SYMBOL_GPL(device_find_child_by_name);
 
-static int match_any(struct device *dev, void *unused)
-{
-	return 1;
-}
-
 /**
  * device_find_any_child - device iterator for locating a child device, if any.
  * @parent: parent struct device
@@ -4124,7 +4119,7 @@ static int match_any(struct device *dev, void *unused)
  */
 struct device *device_find_any_child(struct device *parent)
 {
-	return device_find_child(parent, NULL, match_any);
+	return device_find_child(parent, NULL, device_match_any);
 }
 EXPORT_SYMBOL_GPL(device_find_any_child);
 
diff --git a/include/linux/device.h b/include/linux/device.h
index b2423fca3d45..76f10bdbb4ea 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -1073,8 +1073,8 @@ int device_for_each_child(struct device *dev, void *data,
 			  int (*fn)(struct device *dev, void *data));
 int device_for_each_child_reverse(struct device *dev, void *data,
 				  int (*fn)(struct device *dev, void *data));
-struct device *device_find_child(struct device *dev, void *data,
-				 int (*match)(struct device *dev, void *data));
+struct device *device_find_child(struct device *dev, const void *data,
+				 device_match_t match);
 struct device *device_find_child_by_name(struct device *parent,
 					 const char *name);
 struct device *device_find_any_child(struct device *parent);

-- 
2.34.1