greybus: hd: make host device a device

Make the host device a proper device in the kernel device model.

Host devices will be our new greybus-bus root devices.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/connection.c

@@ -55,7 +55,7 @@ void greybus_data_rcvd(struct gb_host_device *hd, u16 cport_id,
 
 	connection = gb_connection_hd_find(hd, cport_id);
 	if (!connection) {
-		dev_err(hd->parent,
+		dev_err(&hd->dev,
 			"nonexistent connection (%zu bytes dropped)\n", length);
 		return;
 	}
@@ -196,7 +196,7 @@ static int gb_connection_hd_cport_enable(struct gb_connection *connection)
 
 	ret = hd->driver->cport_enable(hd, connection->hd_cport_id);
 	if (ret) {
-		dev_err(hd->parent,
+		dev_err(&hd->dev,
 			"failed to enable host cport: %d\n", ret);
 		return ret;
 	}
@@ -502,7 +502,7 @@ int gb_connection_bind_protocol(struct gb_connection *connection)
 				   connection->major,
 				   connection->minor);
 	if (!protocol) {
-		dev_warn(connection->hd->parent,
+		dev_warn(&connection->hd->dev,
 				"protocol 0x%02hhx version %hhu.%hhu not found\n",
 				connection->protocol_id,
 				connection->major, connection->minor);

drivers/staging/greybus/core.c

@@ -77,6 +77,7 @@ static int greybus_module_match(struct device *dev, struct device_driver *drv)
 
 static int greybus_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
+	struct gb_host_device *hd = NULL;
 	struct gb_module *module = NULL;
 	struct gb_interface *intf = NULL;
 	struct gb_bundle *bundle = NULL;
@@ -89,7 +90,9 @@ static int greybus_uevent(struct device *dev, struct kobj_uevent_env *env)
 		return 0;
 	}
 
-	if (is_gb_module(dev)) {
+	if (is_gb_host_device(dev)) {
+		hd = to_gb_host_device(dev);
+	} else if (is_gb_module(dev)) {
 		module = to_gb_module(dev);
 	} else if (is_gb_interface(dev)) {
 		intf = to_gb_interface(dev);
@@ -196,6 +199,12 @@ static int __init gb_init(void)
 		goto error_bus;
 	}
 
+	retval = gb_hd_init();
+	if (retval) {
+		pr_err("gb_hd_init failed (%d)\n", retval);
+		goto error_hd;
+	}
+
 	retval = gb_operation_init();
 	if (retval) {
 		pr_err("gb_operation_init failed (%d)\n", retval);
@@ -237,6 +246,8 @@ static int __init gb_init(void)
 error_endo:
 	gb_operation_exit();
 error_operation:
+	gb_hd_exit();
+error_hd:
 	bus_unregister(&greybus_bus_type);
 error_bus:
 	gb_debugfs_cleanup();
@@ -252,6 +263,7 @@ static void __exit gb_exit(void)
 	gb_control_protocol_exit();
 	gb_endo_exit();
 	gb_operation_exit();
+	gb_hd_exit();
 	bus_unregister(&greybus_bus_type);
 	gb_debugfs_cleanup();
 	tracepoint_synchronize_unregister();

drivers/staging/greybus/endo.c

@@ -219,7 +219,7 @@ static bool validate_front_ribs(struct gb_host_device *hd,
 		layout->front_ribs = 0x5;
 		break;
 	default:
-		dev_err(hd->parent,
+		dev_err(&hd->dev,
 			"%s: Invalid endo front mask 0x%02x, id 0x%04x\n",
 			__func__, front_mask, endo_id);
 		return false;
@@ -266,21 +266,21 @@ static bool validate_back_ribs(struct gb_host_device *hd,
 	right_ribs = endo_back_right_ribs(endo_id, max_ribs);
 
 	if (!single_cross_rib(left_ribs, right_ribs)) {
-		dev_err(hd->parent,
+		dev_err(&hd->dev,
 			"%s: More than one spanning rib (left 0x%02x right 0x%02x), id 0x%04x\n",
 			__func__, left_ribs, right_ribs, endo_id);
 		return false;
 	}
 
 	if (modules_oversized(max_ribs, left_ribs)) {
-			dev_err(hd->parent,
+			dev_err(&hd->dev,
 				"%s: Oversized module (left) 0x%02x, id 0x%04x\n",
 				__func__, left_ribs, endo_id);
 			return false;
 	}
 
 	if (modules_oversized(max_ribs, right_ribs)) {
-			dev_err(hd->parent,
+			dev_err(&hd->dev,
 				"%s: Oversized module (Right) 0x%02x, id 0x%04x\n",
 				__func__, right_ribs, endo_id);
 			return false;
@@ -306,7 +306,7 @@ static bool validate_back_ribs(struct gb_host_device *hd,
 	 * are of different widths.
 	 */
 	if (max_ribs != ENDO_BACK_RIBS_MEDIUM && left_ribs < right_ribs) {
-		dev_err(hd->parent, "%s: Non-canonical endo id 0x%04x\n", __func__,
+		dev_err(&hd->dev, "%s: Non-canonical endo id 0x%04x\n", __func__,
 			endo_id);
 		return false;
 	}
@@ -334,7 +334,7 @@ static int gb_endo_validate_id(struct gb_host_device *hd,
 		/* Mini Endo type */
 		layout->max_ribs = ENDO_BACK_RIBS_MINI;
 	} else {
-		dev_err(hd->parent, "%s: Invalid endo type, id 0x%04x\n",
+		dev_err(&hd->dev, "%s: Invalid endo type, id 0x%04x\n",
 			__func__, endo_id);
 		return -EINVAL;
 	}
@@ -447,11 +447,11 @@ static int gb_endo_register(struct gb_host_device *hd,
 
 	endo->dev_id = dev_id;
 
-	endo->dev.parent = hd->parent;
+	endo->dev.parent = &hd->dev;
 	endo->dev.bus = &greybus_bus_type;
 	endo->dev.type = &greybus_endo_type;
 	endo->dev.groups = endo_groups;
-	endo->dev.dma_mask = hd->parent->dma_mask;
+	endo->dev.dma_mask = hd->dev.dma_mask;
 	device_initialize(&endo->dev);
 	dev_set_name(&endo->dev, "endo%hu", endo->dev_id);
 
@@ -463,7 +463,7 @@ static int gb_endo_register(struct gb_host_device *hd,
 
 	retval = device_add(&endo->dev);
 	if (retval) {
-		dev_err(hd->parent, "failed to add endo device of id 0x%04x\n",
+		dev_err(&hd->dev, "failed to add endo device of id 0x%04x\n",
 			endo->id);
 		put_device(&endo->dev);
 	}

drivers/staging/greybus/greybus.h

@@ -104,11 +104,17 @@ struct dentry *gb_debugfs_get(void);
 
 extern struct bus_type greybus_bus_type;
 
+extern struct device_type greybus_hd_type;
 extern struct device_type greybus_endo_type;
 extern struct device_type greybus_module_type;
 extern struct device_type greybus_interface_type;
 extern struct device_type greybus_bundle_type;
 
+static inline int is_gb_host_device(const struct device *dev)
+{
+	return dev->type == &greybus_hd_type;
+}
+
 static inline int is_gb_endo(const struct device *dev)
 {
 	return dev->type == &greybus_endo_type;

drivers/staging/greybus/greybus_trace.h

@@ -114,13 +114,13 @@ DECLARE_EVENT_CLASS(gb_host_device,
 	TP_ARGS(hd, intf_cport_id, payload_size),
 
 	TP_STRUCT__entry(
-		__string(name, dev_name(hd->parent))
+		__string(name, dev_name(&hd->dev))
 		__field(u16, intf_cport_id)
 		__field(size_t, payload_size)
 	),
 
 	TP_fast_assign(
-		__assign_str(name, dev_name(hd->parent))
+		__assign_str(name, dev_name(&hd->dev))
 		__entry->intf_cport_id = intf_cport_id;
 		__entry->payload_size = payload_size;
 	),

drivers/staging/greybus/hd.c

@@ -14,26 +14,30 @@
 
 #include "greybus.h"
 
-static DEFINE_MUTEX(hd_mutex);
 
+static struct ida gb_hd_bus_id_map;
 
-static void free_hd(struct kref *kref)
+static void gb_hd_release(struct device *dev)
 {
-	struct gb_host_device *hd;
-
-	hd = container_of(kref, struct gb_host_device, kref);
+	struct gb_host_device *hd = to_gb_host_device(dev);
 
+	ida_simple_remove(&gb_hd_bus_id_map, hd->bus_id);
 	ida_destroy(&hd->cport_id_map);
 	kfree(hd);
-	mutex_unlock(&hd_mutex);
 }
 
+struct device_type greybus_hd_type = {
+	.name		= "greybus_host_device",
+	.release	= gb_hd_release,
+};
+
 struct gb_host_device *gb_hd_create(struct gb_hd_driver *driver,
 					struct device *parent,
 					size_t buffer_size_max,
 					size_t num_cports)
 {
 	struct gb_host_device *hd;
+	int ret;
 
 	/*
 	 * Validate that the driver implements all of the callbacks
@@ -68,8 +72,21 @@ struct gb_host_device *gb_hd_create(struct gb_hd_driver *driver,
 	if (!hd)
 		return ERR_PTR(-ENOMEM);
 
-	kref_init(&hd->kref);
-	hd->parent = parent;
+	hd->dev.parent = parent;
+	hd->dev.bus = &greybus_bus_type;
+	hd->dev.type = &greybus_hd_type;
+	hd->dev.dma_mask = hd->dev.parent->dma_mask;
+	device_initialize(&hd->dev);
+
+	ret = ida_simple_get(&gb_hd_bus_id_map, 1, 0, GFP_KERNEL);
+	if (ret < 0) {
+		kfree(hd);
+		return ERR_PTR(ret);
+	}
+
+	hd->bus_id = ret;
+	dev_set_name(&hd->dev, "greybus%d", hd->bus_id);
+
 	hd->driver = driver;
 	INIT_LIST_HEAD(&hd->interfaces);
 	INIT_LIST_HEAD(&hd->connections);
@@ -83,6 +100,12 @@ EXPORT_SYMBOL_GPL(gb_hd_create);
 
 int gb_hd_add(struct gb_host_device *hd)
 {
+	int ret;
+
+	ret = device_add(&hd->dev);
+	if (ret)
+		return ret;
+
 	/*
 	 * Initialize AP's SVC protocol connection:
 	 *
@@ -93,8 +116,10 @@ int gb_hd_add(struct gb_host_device *hd)
 	 * time we will create a fully initialized svc-connection, as we need
 	 * endo-id and AP's interface id for that.
 	 */
-	if (!gb_ap_svc_connection_create(hd))
+	if (!gb_ap_svc_connection_create(hd)) {
+		device_del(&hd->dev);
 		return -ENOMEM;
+	}
 
 	return 0;
 }
@@ -113,11 +138,25 @@ void gb_hd_del(struct gb_host_device *hd)
 	/* Is the SVC still using the partially uninitialized connection ? */
 	if (hd->initial_svc_connection)
 		gb_connection_destroy(hd->initial_svc_connection);
+
+	device_del(&hd->dev);
 }
 EXPORT_SYMBOL_GPL(gb_hd_del);
 
 void gb_hd_put(struct gb_host_device *hd)
 {
-	kref_put_mutex(&hd->kref, free_hd, &hd_mutex);
+	put_device(&hd->dev);
 }
 EXPORT_SYMBOL_GPL(gb_hd_put);
+
+int __init gb_hd_init(void)
+{
+	ida_init(&gb_hd_bus_id_map);
+
+	return 0;
+}
+
+void gb_hd_exit(void)
+{
+	ida_destroy(&gb_hd_bus_id_map);
+}

drivers/staging/greybus/hd.h

@@ -26,8 +26,8 @@ struct gb_hd_driver {
 };
 
 struct gb_host_device {
-	struct kref kref;
-	struct device *parent;
+	struct device dev;
+	int bus_id;
 	const struct gb_hd_driver *driver;
 
 	struct list_head interfaces;
@@ -47,6 +47,7 @@ struct gb_host_device {
 	/* Private data for the host driver */
 	unsigned long hd_priv[0] __aligned(sizeof(s64));
 };
+#define to_gb_host_device(d) container_of(d, struct gb_host_device, d)
 
 struct gb_host_device *gb_hd_create(struct gb_hd_driver *driver,
 					struct device *parent,
@@ -56,4 +57,7 @@ int gb_hd_add(struct gb_host_device *hd);
 void gb_hd_del(struct gb_host_device *hd);
 void gb_hd_put(struct gb_host_device *hd);
 
+int gb_hd_init(void);
+void gb_hd_exit(void);
+
 #endif	/* __HD_H */

drivers/staging/greybus/interface.c

@@ -149,7 +149,7 @@ struct gb_interface *gb_interface_create(struct gb_host_device *hd,
 	intf->dev.bus = &greybus_bus_type;
 	intf->dev.type = &greybus_interface_type;
 	intf->dev.groups = interface_groups;
-	intf->dev.dma_mask = hd->parent->dma_mask;
+	intf->dev.dma_mask = hd->dev.dma_mask;
 	device_initialize(&intf->dev);
 	dev_set_name(&intf->dev, "%s:%d", dev_name(&module->dev), interface_id);
 

drivers/staging/greybus/svc.c

@@ -46,7 +46,7 @@ gb_ap_svc_connection_create(struct gb_host_device *hd)
 {
 	struct gb_connection *connection;
 
-	connection = gb_connection_create_range(hd, NULL, hd->parent,
+	connection = gb_connection_create_range(hd, NULL, &hd->dev,
 						GB_SVC_CPORT_ID,
 						GREYBUS_PROTOCOL_SVC,
 						GB_SVC_CPORT_ID,