devres: Add devres_release()

APIs using devres frequently want to implement a "remove and free the
resource" operation so it seems sensible that they should be able to
just have devres do the freeing for them since that's a big part of what
devres is all about.

Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: broonie

drivers/base/devres.c

@@ -330,6 +330,37 @@ int devres_destroy(struct device *dev, dr_release_t release,
 }
 EXPORT_SYMBOL_GPL(devres_destroy);
 
+
+/**
+ * devres_release - Find a device resource and destroy it, calling release
+ * @dev: Device to find resource from
+ * @release: Look for resources associated with this release function
+ * @match: Match function (optional)
+ * @match_data: Data for the match function
+ *
+ * Find the latest devres of @dev associated with @release and for
+ * which @match returns 1.  If @match is NULL, it's considered to
+ * match all.  If found, the resource is removed atomically, the
+ * release function called and the resource freed.
+ *
+ * RETURNS:
+ * 0 if devres is found and freed, -ENOENT if not found.
+ */
+int devres_release(struct device *dev, dr_release_t release,
+		   dr_match_t match, void *match_data)
+{
+	void *res;
+
+	res = devres_remove(dev, release, match, match_data);
+	if (unlikely(!res))
+		return -ENOENT;
+
+	(*release)(dev, res);
+	devres_free(res);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devres_release);
+
 static int remove_nodes(struct device *dev,
 			struct list_head *first, struct list_head *end,
 			struct list_head *todo)

include/linux/device.h

@@ -541,6 +541,8 @@ extern void *devres_remove(struct device *dev, dr_release_t release,
 			   dr_match_t match, void *match_data);
 extern int devres_destroy(struct device *dev, dr_release_t release,
 			  dr_match_t match, void *match_data);
+extern int devres_release(struct device *dev, dr_release_t release,
+			  dr_match_t match, void *match_data);
 
 /* devres group */
 extern void * __must_check devres_open_group(struct device *dev, void *id,