fpga: bridge: add devm_fpga_bridge_create

Add devm_fpga_bridge_create() which is the managed
version of fpga_bridge_create().

Change current bridge drivers to use
devm_fpga_bridge_create().

Signed-off-by: Alan Tull <atull@kernel.org>
Suggested-by: Federico Vaga <federico.vaga@cern.ch>
Acked-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 59 insertions, 9 deletions

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index c983dac97501..80bd8f1b2aa6 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -324,6 +324,9 @@ ATTRIBUTE_GROUPS(fpga_bridge);
  * @br_ops:	pointer to structure of fpga bridge ops
  * @priv:	FPGA bridge private data
  *
+ * The caller of this function is responsible for freeing the bridge with
+ * fpga_bridge_free().  Using devm_fpga_bridge_create() instead is recommended.
+ *
  * Return: struct fpga_bridge or NULL
  */
 struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
@@ -378,8 +381,8 @@ error_kfree:
 EXPORT_SYMBOL_GPL(fpga_bridge_create);
 
 /**
- * fpga_bridge_free - free a fpga bridge and its id
- * @bridge:	FPGA bridge struct created by fpga_bridge_create
+ * fpga_bridge_free - free a fpga bridge created by fpga_bridge_create()
+ * @bridge:	FPGA bridge struct
  */
 void fpga_bridge_free(struct fpga_bridge *bridge)
 {
@@ -388,9 +391,56 @@ void fpga_bridge_free(struct fpga_bridge *bridge)
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_free);
 
+static void devm_fpga_bridge_release(struct device *dev, void *res)
+{
+	struct fpga_bridge *bridge = *(struct fpga_bridge **)res;
+
+	fpga_bridge_free(bridge);
+}
+
 /**
- * fpga_bridge_register - register a fpga bridge
- * @bridge:	FPGA bridge struct created by fpga_bridge_create
+ * devm_fpga_bridge_create - create and init a managed struct fpga_bridge
+ * @dev:	FPGA bridge device from pdev
+ * @name:	FPGA bridge name
+ * @br_ops:	pointer to structure of fpga bridge ops
+ * @priv:	FPGA bridge private data
+ *
+ * This function is intended for use in a FPGA bridge driver's probe function.
+ * After the bridge driver creates the struct with devm_fpga_bridge_create(), it
+ * should register the bridge with fpga_bridge_register().  The bridge driver's
+ * remove function should call fpga_bridge_unregister().  The bridge struct
+ * allocated with this function will be freed automatically on driver detach.
+ * This includes the case of a probe function returning error before calling
+ * fpga_bridge_register(), the struct will still get cleaned up.
+ *
+ *  Return: struct fpga_bridge or NULL
+ */
+struct fpga_bridge
+*devm_fpga_bridge_create(struct device *dev, const char *name,
+			 const struct fpga_bridge_ops *br_ops, void *priv)
+{
+	struct fpga_bridge **ptr, *bridge;
+
+	ptr = devres_alloc(devm_fpga_bridge_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return NULL;
+
+	bridge = fpga_bridge_create(dev, name, br_ops, priv);
+	if (!bridge) {
+		devres_free(ptr);
+	} else {
+		*ptr = bridge;
+		devres_add(dev, ptr);
+	}
+
+	return bridge;
+}
+EXPORT_SYMBOL_GPL(devm_fpga_bridge_create);
+
+/**
+ * fpga_bridge_register - register a FPGA bridge
+ *
+ * @bridge: FPGA bridge struct
  *
  * Return: 0 for success, error code otherwise.
  */
@@ -412,8 +462,11 @@ int fpga_bridge_register(struct fpga_bridge *bridge)
 EXPORT_SYMBOL_GPL(fpga_bridge_register);
 
 /**
- * fpga_bridge_unregister - unregister and free a fpga bridge
- * @bridge:	FPGA bridge struct created by fpga_bridge_create
+ * fpga_bridge_unregister - unregister a FPGA bridge
+ *
+ * @bridge: FPGA bridge struct
+ *
+ * This function is intended for use in a FPGA bridge driver's remove function.
  */
 void fpga_bridge_unregister(struct fpga_bridge *bridge)
 {
@@ -430,9 +483,6 @@ EXPORT_SYMBOL_GPL(fpga_bridge_unregister);
 
 static void fpga_bridge_dev_release(struct device *dev)
 {
-	struct fpga_bridge *bridge = to_fpga_bridge(dev);
-
-	fpga_bridge_free(bridge);
 }
 
 static int __init fpga_bridge_dev_init(void)