fpga: bridge: change api, don't use drvdata

Change fpga_bridge_register to not set drvdata.  This is to support
the case where a PCIe device can have more than one bridge.

Add API functions to create/free the fpga bridge struct. Change
fpga_bridge_register/unregister to take FPGA bridge struct as
the only parameter.

  struct fpga_bridge
  *fpga_bridge_create(struct device *dev, const char *name,
                      const struct fpga_bridge_ops *br_ops,
                      void *priv);
  void fpga_bridge_free(struct fpga_bridge *br);
  int fpga_bridge_register(struct fpga_bridge *br);
  void fpga_bridge_unregister(struct fpga_bridge *br);

Update the drivers that call fpga_bridge_register with the new API.

Signed-off-by: Alan Tull <atull@kernel.org>
Reported-by: Jiuyue Ma <majiuyue@huawei.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 31bd2c5..2db1573 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -328,28 +328,29 @@ static struct attribute *fpga_bridge_attrs[] = {
 ATTRIBUTE_GROUPS(fpga_bridge);
 
 /**
- * fpga_bridge_register - register a fpga bridge driver
+ * fpga_bridge_create - create and initialize a 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
  *
- * Return: 0 for success, error code otherwise.
+ * Return: struct fpga_bridge or NULL
  */
-int fpga_bridge_register(struct device *dev, const char *name,
-			 const struct fpga_bridge_ops *br_ops, void *priv)
+struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
+				       const struct fpga_bridge_ops *br_ops,
+				       void *priv)
 {
 	struct fpga_bridge *bridge;
 	int id, ret = 0;
 
 	if (!name || !strlen(name)) {
 		dev_err(dev, "Attempt to register with no name!\n");
-		return -EINVAL;
+		return NULL;
 	}
 
 	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
 	if (!bridge)
-		return -ENOMEM;
+		return NULL;
 
 	id = ida_simple_get(&fpga_bridge_ida, 0, 0, GFP_KERNEL);
 	if (id < 0) {
@@ -370,40 +371,62 @@ int fpga_bridge_register(struct device *dev, const char *name,
 	bridge->dev.parent = dev;
 	bridge->dev.of_node = dev->of_node;
 	bridge->dev.id = id;
-	dev_set_drvdata(dev, bridge);
 
 	ret = dev_set_name(&bridge->dev, "br%d", id);
 	if (ret)
 		goto error_device;
 
-	ret = device_add(&bridge->dev);
-	if (ret)
-		goto error_device;
-
-	of_platform_populate(dev->of_node, NULL, NULL, dev);
-
-	dev_info(bridge->dev.parent, "fpga bridge [%s] registered\n",
-		 bridge->name);
-
-	return 0;
+	return bridge;
 
 error_device:
 	ida_simple_remove(&fpga_bridge_ida, id);
 error_kfree:
 	kfree(bridge);
 
-	return ret;
+	return NULL;
+}
+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
+ */
+void fpga_bridge_free(struct fpga_bridge *bridge)
+{
+	ida_simple_remove(&fpga_bridge_ida, bridge->dev.id);
+	kfree(bridge);
+}
+EXPORT_SYMBOL_GPL(fpga_bridge_free);
+
+/**
+ * fpga_bridge_register - register a fpga bridge
+ * @bridge:	FPGA bridge struct created by fpga_bridge_create
+ *
+ * Return: 0 for success, error code otherwise.
+ */
+int fpga_bridge_register(struct fpga_bridge *bridge)
+{
+	struct device *dev = &bridge->dev;
+	int ret;
+
+	ret = device_add(dev);
+	if (ret)
+		return ret;
+
+	of_platform_populate(dev->of_node, NULL, NULL, dev);
+
+	dev_info(dev->parent, "fpga bridge [%s] registered\n", bridge->name);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_register);
 
 /**
  * fpga_bridge_unregister - unregister a fpga bridge driver
- * @dev: FPGA bridge device from pdev
+ * @bridge:	FPGA bridge struct created by fpga_bridge_create
  */
-void fpga_bridge_unregister(struct device *dev)
+void fpga_bridge_unregister(struct fpga_bridge *bridge)
 {
-	struct fpga_bridge *bridge = dev_get_drvdata(dev);
-
 	/*
 	 * If the low level driver provides a method for putting bridge into
 	 * a desired state upon unregister, do it.
@@ -419,8 +442,7 @@ static void fpga_bridge_dev_release(struct device *dev)
 {
 	struct fpga_bridge *bridge = to_fpga_bridge(dev);
 
-	ida_simple_remove(&fpga_bridge_ida, bridge->dev.id);
-	kfree(bridge);
+	fpga_bridge_free(bridge);
 }
 
 static int __init fpga_bridge_dev_init(void)