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>

1 files changed, 49 insertions, 10 deletions

diff --git a/drivers/staging/greybus/hd.c b/drivers/staging/greybus/hd.c
index 3446fec..88d2f01 100644
--- a/drivers/staging/greybus/hd.c
+++ b/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);
+}