greybus: legacy: add legacy-protocol bundle driver

Add the first Greybus bundle driver that will be used when transitioning
from legacy Greybus protocols to bundle drivers.

The legacy-protocol driver initially binds to all current bundle classes.

In order to avoid having to update current module-loading scripts, keep
this driver internal to greybus core at least until modalias support is
added. Note that this prevents unloading any protocol drivers without
first tearing down the host device due to a circular module dependency.

Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

7 files changed, 125 insertions, 21 deletions

diff --git a/drivers/staging/greybus/Makefile b/drivers/staging/greybus/Makefile
index b1272cbd55ee..1e24509bdb4d 100644
--- a/drivers/staging/greybus/Makefile
+++ b/drivers/staging/greybus/Makefile
@@ -9,7 +9,8 @@ greybus-y :=	core.o		\
 		control.o	\
 		svc.o		\
 		firmware.o	\
-		operation.o
+		operation.o	\
+		legacy.o
 
 gb-phy-y :=	gpbridge.o	\
 		sdio.o	\
diff --git a/drivers/staging/greybus/bundle.c b/drivers/staging/greybus/bundle.c
index fb775ff1895d..ec52bdecb5c1 100644
--- a/drivers/staging/greybus/bundle.c
+++ b/drivers/staging/greybus/bundle.c
@@ -152,21 +152,11 @@ int gb_bundle_add(struct gb_bundle *bundle)
 	return 0;
 }
 
-static void gb_bundle_connections_exit(struct gb_bundle *bundle)
-{
-	struct gb_connection *connection;
-
-	list_for_each_entry(connection, &bundle->connections, bundle_links)
-		gb_connection_exit(connection);
-}
-
 /*
  * Tear down a previously set up bundle.
  */
 void gb_bundle_destroy(struct gb_bundle *bundle)
 {
-	gb_bundle_connections_exit(bundle);
-
 	if (device_is_registered(&bundle->dev))
 		device_del(&bundle->dev);
 
diff --git a/drivers/staging/greybus/connection.c b/drivers/staging/greybus/connection.c
index 6295d28a4be4..21e6eb52c437 100644
--- a/drivers/staging/greybus/connection.c
+++ b/drivers/staging/greybus/connection.c
@@ -464,6 +464,7 @@ err_unbind_protocol:
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(gb_connection_init);
 
 void gb_connection_exit(struct gb_connection *connection)
 {
@@ -482,6 +483,7 @@ void gb_connection_exit(struct gb_connection *connection)
 
 	gb_connection_unbind_protocol(connection);
 }
+EXPORT_SYMBOL_GPL(gb_connection_exit);
 
 /*
  * Tear down a previously set up connection.
diff --git a/drivers/staging/greybus/core.c b/drivers/staging/greybus/core.c
index 0e2f99df6cfa..28f48d79b005 100644
--- a/drivers/staging/greybus/core.c
+++ b/drivers/staging/greybus/core.c
@@ -12,6 +12,7 @@
 #define CREATE_TRACE_POINTS
 #include "greybus.h"
 #include "greybus_trace.h"
+#include "legacy.h"
 
 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_host_device_send);
 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_host_device_recv);
@@ -240,8 +241,16 @@ static int __init gb_init(void)
 		goto error_firmware;
 	}
 
+	retval = gb_legacy_init();
+	if (retval) {
+		pr_err("gb_legacy_init failed\n");
+		goto error_legacy;
+	}
+
 	return 0;	/* Success */
 
+error_legacy:
+	gb_firmware_protocol_exit();
 error_firmware:
 	gb_svc_protocol_exit();
 error_svc:
@@ -261,6 +270,7 @@ module_init(gb_init);
 
 static void __exit gb_exit(void)
 {
+	gb_legacy_exit();
 	gb_firmware_protocol_exit();
 	gb_svc_protocol_exit();
 	gb_control_protocol_exit();
diff --git a/drivers/staging/greybus/interface.c b/drivers/staging/greybus/interface.c
index edac2383e492..c3453502ae22 100644
--- a/drivers/staging/greybus/interface.c
+++ b/drivers/staging/greybus/interface.c
@@ -183,7 +183,6 @@ void gb_interfaces_remove(struct gb_host_device *hd)
 int gb_interface_init(struct gb_interface *intf, u8 device_id)
 {
 	struct gb_bundle *bundle, *tmp;
-	struct gb_connection *connection;
 	int ret, size;
 	void *manifest;
 
@@ -242,15 +241,6 @@ int gb_interface_init(struct gb_interface *intf, u8 device_id)
 			gb_bundle_destroy(bundle);
 			continue;
 		}
-
-		list_for_each_entry(connection, &bundle->connections,
-							bundle_links) {
-			ret = gb_connection_init(connection);
-			if (ret)
-				break;
-		}
-		if (ret)
-			gb_bundle_destroy(bundle);
 	}
 
 	ret = 0;
diff --git a/drivers/staging/greybus/legacy.c b/drivers/staging/greybus/legacy.c
new file mode 100644
index 000000000000..26a7d1a05256
--- /dev/null
+++ b/drivers/staging/greybus/legacy.c
@@ -0,0 +1,95 @@
+/*
+ * Greybus legacy-protocol driver
+ *
+ * Copyright 2015 Google Inc.
+ * Copyright 2015 Linaro Ltd.
+ *
+ * Released under the GPLv2 only.
+ */
+
+#include "greybus.h"
+#include "legacy.h"
+
+static int legacy_probe(struct gb_bundle *bundle,
+			const struct greybus_bundle_id *id)
+{
+	struct gb_connection *connection;
+	int ret;
+
+	dev_dbg(&bundle->dev, "%s - bundle class = 0x%02x\n", __func__,
+			bundle->class);
+
+	list_for_each_entry(connection, &bundle->connections, bundle_links) {
+		dev_dbg(&bundle->dev, "enabling connection %s\n",
+				connection->name);
+
+		ret = gb_connection_init(connection);
+		if (ret)
+			goto err_connections_disable;
+	}
+
+	return 0;
+
+err_connections_disable:
+	list_for_each_entry_reverse(connection, &bundle->connections,
+							bundle_links) {
+		gb_connection_exit(connection);
+	}
+
+	return ret;
+}
+
+static void legacy_disconnect(struct gb_bundle *bundle)
+{
+	struct gb_connection *connection;
+
+	dev_dbg(&bundle->dev, "%s - bundle class = 0x%02x\n", __func__,
+			bundle->class);
+
+	list_for_each_entry_reverse(connection, &bundle->connections,
+							bundle_links) {
+		gb_connection_exit(connection);
+	}
+}
+
+static const struct greybus_bundle_id legacy_id_table[] = {
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_GPIO) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_I2C) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_UART) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_HID) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_USB) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_SDIO) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_POWER_SUPPLY) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_PWM) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_SPI) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_DISPLAY) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_CAMERA) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_SENSOR) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_LIGHTS) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_VIBRATOR) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_LOOPBACK) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_AUDIO_MGMT) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_AUDIO_DATA) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_SVC) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_FIRMWARE) },
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_RAW) },
+	{ }
+};
+MODULE_DEVICE_TABLE(greybus, legacy_id_table);
+
+static struct greybus_driver legacy_driver = {
+	.name		= "legacy",
+	.probe		= legacy_probe,
+	.disconnect	= legacy_disconnect,
+	.id_table	= legacy_id_table,
+};
+
+int gb_legacy_init(void)
+{
+	return greybus_register(&legacy_driver);
+}
+
+void gb_legacy_exit(void)
+{
+	greybus_deregister(&legacy_driver);
+}
diff --git a/drivers/staging/greybus/legacy.h b/drivers/staging/greybus/legacy.h
new file mode 100644
index 000000000000..2177f6aaed3c
--- /dev/null
+++ b/drivers/staging/greybus/legacy.h
@@ -0,0 +1,16 @@
+/*
+ * Greybus legacy-protocol driver
+ *
+ * Copyright 2015 Google Inc.
+ * Copyright 2015 Linaro Ltd.
+ *
+ * Released under the GPLv2 only.
+ */
+
+#ifndef __LEGACY_H
+#define __LEGACY_H
+
+int gb_legacy_init(void);
+void gb_legacy_exit(void);
+
+#endif /* __LEGACY_H */