greybus: constify the struct device_type usage

Since commit aed65af1 ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type. Move the
greybus_hd_type, greybus_module_type, greybus_interface_type,
greybus_control_type, greybus_bundle_type and greybus_svc_type variables to
be constant structures as well, placing it into read-only memory which can
not be modified at runtime.
Signed-off-by: "Ricardo B. Marliere" <ricardo@marliere.net>
Reviewed-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20240219-device_cleanup-greybus-v1-1-babb3f65e8cc@marliere.netSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/greybus/bundle.c

@@ -166,7 +166,7 @@ static const struct dev_pm_ops gb_bundle_pm_ops = {
 	SET_RUNTIME_PM_OPS(gb_bundle_suspend, gb_bundle_resume, gb_bundle_idle)
 };
 
-struct device_type greybus_bundle_type = {
+const struct device_type greybus_bundle_type = {
 	.name =		"greybus_bundle",
 	.release =	gb_bundle_release,
 	.pm =		&gb_bundle_pm_ops,

drivers/greybus/control.c

@@ -436,7 +436,7 @@ static void gb_control_release(struct device *dev)
 	kfree(control);
 }
 
-struct device_type greybus_control_type = {
+const struct device_type greybus_control_type = {
 	.name =		"greybus_control",
 	.release =	gb_control_release,
 };

drivers/greybus/hd.c

@@ -116,7 +116,7 @@ static void gb_hd_release(struct device *dev)
 	kfree(hd);
 }
 
-struct device_type greybus_hd_type = {
+const struct device_type greybus_hd_type = {
 	.name		= "greybus_host_device",
 	.release	= gb_hd_release,
 };

drivers/greybus/interface.c

@@ -765,7 +765,7 @@ static const struct dev_pm_ops gb_interface_pm_ops = {
 			   gb_interface_runtime_idle)
 };
 
-struct device_type greybus_interface_type = {
+const struct device_type greybus_interface_type = {
 	.name =		"greybus_interface",
 	.release =	gb_interface_release,
 	.pm =		&gb_interface_pm_ops,

drivers/greybus/module.c

@@ -81,7 +81,7 @@ static void gb_module_release(struct device *dev)
 	kfree(module);
 }
 
-struct device_type greybus_module_type = {
+const struct device_type greybus_module_type = {
 	.name		= "greybus_module",
 	.release	= gb_module_release,
 };

drivers/greybus/svc.c

@@ -1305,7 +1305,7 @@ static void gb_svc_release(struct device *dev)
 	kfree(svc);
 }
 
-struct device_type greybus_svc_type = {
+const struct device_type greybus_svc_type = {
 	.name		= "greybus_svc",
 	.release	= gb_svc_release,
 };

include/linux/greybus.h

@@ -106,12 +106,12 @@ struct dentry *gb_debugfs_get(void);
 
 extern const struct bus_type greybus_bus_type;
 
-extern struct device_type greybus_hd_type;
-extern struct device_type greybus_module_type;
-extern struct device_type greybus_interface_type;
-extern struct device_type greybus_control_type;
-extern struct device_type greybus_bundle_type;
-extern struct device_type greybus_svc_type;
+extern const struct device_type greybus_hd_type;
+extern const struct device_type greybus_module_type;
+extern const struct device_type greybus_interface_type;
+extern const struct device_type greybus_control_type;
+extern const struct device_type greybus_bundle_type;
+extern const struct device_type greybus_svc_type;
 
 static inline int is_gb_host_device(const struct device *dev)
 {