Staging: hv: util: Make hv_utils a vmbus device driver

In preperation for supporting auto-loading the util driver, make
the util driver a vmbus driver.
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/hv/hv_util.c

@@ -36,6 +36,8 @@ static u8 *shut_txf_buf;
 static u8 *time_txf_buf;
 static u8 *hbeat_txf_buf;
 
+static const char *driver_name = "hv_util";
+
 static void shutdown_onchannelcallback(void *context)
 {
 	struct vmbus_channel *channel = context;
@@ -210,6 +212,63 @@ static void heartbeat_onchannelcallback(void *context)
 	}
 }
 
+/*
+ * The devices managed by the util driver don't need any additional
+ * setup.
+ */
+static int util_probe(struct hv_device *dev)
+{
+	return 0;
+}
+
+static int util_remove(struct hv_device *dev)
+{
+	return 0;
+}
+
+static const struct hv_vmbus_device_id id_table[] = {
+	{
+		/* Shutdown guid */
+		.guid = {
+			0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
+			0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
+		}
+	},
+	{
+		/* Time synch guid */
+		.guid = {
+			0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
+			0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
+		}
+	},
+	{
+		/* Heartbeat guid */
+		.guid = {
+			0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
+			0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
+		}
+	},
+	{
+		/* KVP guid */
+		.guid = {
+			0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
+			0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6
+		}
+	},
+	{
+		.guid = { }
+	},
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+/* The one and only one */
+static  struct hv_driver util_drv = {
+	.id_table = id_table,
+	.probe =  util_probe,
+	.remove =  util_remove,
+};
+
 static const struct pci_device_id __initconst
 hv_utils_pci_table[] __maybe_unused = {
 	{ PCI_DEVICE(0x1414, 0x5353) }, /* Hyper-V emulated VGA controller */
@@ -264,7 +323,9 @@ static int __init init_hyperv_utils(void)
 
 	hv_cb_utils[HV_KVP_MSG].callback = &hv_kvp_onchannelcallback;
 
-	return 0;
+	util_drv.driver.name = driver_name;
+
+	return vmbus_child_driver_register(&util_drv.driver);
 }
 
 static void exit_hyperv_utils(void)
@@ -296,6 +357,7 @@ static void exit_hyperv_utils(void)
 	kfree(shut_txf_buf);
 	kfree(time_txf_buf);
 	kfree(hbeat_txf_buf);
+	vmbus_child_driver_unregister(&util_drv.driver);
 }
 
 module_init(init_hyperv_utils);