fpga: bridge: make fpga_bridge_class a static const structure

Now that the driver core allows for struct class to be in read-only
memory, move the fpga_bridge_class structure to be declared at build
time placing it into read-only memory, instead of having to be
dynamically allocated at boot time.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20230811073043.52808-1-ivan.orlov0322@gmail.com
Signed-off-by: Xu Yilun <yilun.xu@intel.com>

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 0b76c67..a024be2 100644 (file)
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -14,7 +14,7 @@
 #include <linux/spinlock.h>
 
 static DEFINE_IDA(fpga_bridge_ida);
-static struct class *fpga_bridge_class;
+static const struct class fpga_bridge_class;
 
 /* Lock for adding/removing bridges to linked lists*/
 static DEFINE_SPINLOCK(bridge_list_lock);
@@ -100,7 +100,7 @@ struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
 {
        struct device *dev;
 
-       dev = class_find_device_by_of_node(fpga_bridge_class, np);
+       dev = class_find_device_by_of_node(&fpga_bridge_class, np);
        if (!dev)
                return ERR_PTR(-ENODEV);
 
@@ -127,7 +127,7 @@ struct fpga_bridge *fpga_bridge_get(struct device *dev,
 {
        struct device *bridge_dev;
 
-       bridge_dev = class_find_device(fpga_bridge_class, NULL, dev,
+       bridge_dev = class_find_device(&fpga_bridge_class, NULL, dev,
                                       fpga_bridge_dev_match);
        if (!bridge_dev)
                return ERR_PTR(-ENODEV);
@@ -360,7 +360,7 @@ fpga_bridge_register(struct device *parent, const char *name,
        bridge->priv = priv;
 
        bridge->dev.groups = br_ops->groups;
-       bridge->dev.class = fpga_bridge_class;
+       bridge->dev.class = &fpga_bridge_class;
        bridge->dev.parent = parent;
        bridge->dev.of_node = parent->of_node;
        bridge->dev.id = id;
@@ -416,21 +416,20 @@ static void fpga_bridge_dev_release(struct device *dev)
        kfree(bridge);
 }
 
+static const struct class fpga_bridge_class = {
+       .name = "fpga_bridge",
+       .dev_groups = fpga_bridge_groups,
+       .dev_release = fpga_bridge_dev_release,
+};
+
 static int __init fpga_bridge_dev_init(void)
 {
-       fpga_bridge_class = class_create("fpga_bridge");
-       if (IS_ERR(fpga_bridge_class))
-               return PTR_ERR(fpga_bridge_class);
-
-       fpga_bridge_class->dev_groups = fpga_bridge_groups;
-       fpga_bridge_class->dev_release = fpga_bridge_dev_release;
-
-       return 0;
+       return class_register(&fpga_bridge_class);
 }
 
 static void __exit fpga_bridge_dev_exit(void)
 {
-       class_destroy(fpga_bridge_class);
+       class_unregister(&fpga_bridge_class);
        ida_destroy(&fpga_bridge_ida);
 }