Remove unused usb functions after changing usb modesubmit/tizen_5.5/20200313.073358

After setting the new usb mode, the configfs functions that was not used remain.
For example, changing from rndis mode to sdb mode, /sys/kernel/config/usb_gadget/hal-gadget/rndis.default remains.

A functionfs has to do a few extra things.
 - The socket and service associated with functionfs must be terminated.
 - Umount /dev/usb-funcs/[sdb|mtp]/default
 - Delete /dev/usb-funcs/[sdb|mtp]/default recursively

Change-Id: I2d66f033babd5bea20cfc74d8bf23eb9a89c3be1
(cherry picked from commit 19877fd6f2488dca79d89c5b06f1673a624a5f32)

1 files changed, 107 insertions, 3 deletions

diff --git a/hw/usb_cfs_client_common.c b/hw/usb_cfs_client_common.c
index 66ca48b..10bed2a 100644
--- a/hw/usb_cfs_client_common.c
+++ b/hw/usb_cfs_client_common.c
@@ -659,6 +659,64 @@ umount_ffs:
 	return ret;
 }
 
+static int cfs_cleanup_ffs_service(usbg_function *function)
+{
+	int ret;
+	int index;
+	const char *name;
+	const char *instance;
+	char buf[MAX_INSTANCE_LEN];
+	struct usb_function *usb_function;
+
+	if (!function)
+		return -EINVAL;
+
+	instance = usbg_get_function_instance(function); /* Ex: sdb.default */
+	name = usbg_get_function_type_str(usbg_get_function_type(function)); /* Fixed: ffs */
+
+	index = cfs_find_func(name, instance);
+	if (index < 0)
+		return index;
+
+	usb_function = _available_funcs[index];
+
+	/* stop .socket first and stop .service later becuase of socket activation */
+	if (usb_function->service) {
+		(void)systemd_stop_unit_wait_stopped(usb_function->service, ".socket", -1);
+		(void)systemd_stop_unit_wait_stopped(usb_function->service, ".service", -1);
+	}
+
+	/* umount /dev/usb-funcs/[sdb|mtp]/default and remove it's directory */
+	ret = snprintf(buf, sizeof(buf), "%s%s/%s", USB_FUNCS_PATH, usb_function->name, usb_function->instance);
+	if (ret < 0)
+		return ret;
+
+	ret = umount(buf);
+	if (ret < 0)
+		return ret;
+
+	ret = rmdir(buf);
+	if (ret < 0)
+		return ret;
+
+	/* remove /dev/usb-funcs/[sdb|mtp] directory */
+	ret = snprintf(buf, sizeof(buf), "%s%s", USB_FUNCS_PATH, usb_function->name);
+	if (ret < 0)
+		return ret;
+
+	ret = rmdir(buf);
+	if (ret < 0 && errno != ENOTEMPTY)
+		return ret;
+
+	/* remove /dev/usb-funcs/ directory */
+	ret = rmdir(USB_FUNCS_PATH);
+	if (ret < 0 && errno != ENOTEMPTY)
+		return ret;
+
+	return 0;
+}
+
+
 static int cfs_set_rndis_mac_addr(usbg_gadget *gadget, usbg_function *func)
 {
 	int i, ret;
@@ -796,6 +854,50 @@ static int cfs_cleanup_left_configs(struct cfs_client *cfs_client,
 	return 0;
 }
 
+static int cfs_function_is_binded(struct usbg_gadget *gadget, struct usbg_function *func)
+{
+	usbg_binding *b;
+	usbg_config *config;
+
+	usbg_for_each_config(config, gadget)
+		usbg_for_each_binding(b, config)
+			if (usbg_get_binding_target(b) == func)
+				return 1;
+
+	return 0;
+}
+
+static int cfs_cleanup_unused_function(usbg_gadget *gadget)
+{
+	int ret;
+	usbg_function *function;
+
+	if (!gadget)
+		return -EINVAL;
+
+restart:
+	usbg_for_each_function(function, gadget) {
+		if(cfs_function_is_binded(gadget, function))
+			continue;
+
+		if (usbg_get_function_type(function) == USBG_F_FFS) {
+			ret = cfs_cleanup_ffs_service(function);
+			if (ret)
+				return ret;
+		}
+
+		ret = usbg_rm_function(function, USBG_RM_RECURSE);
+		if (ret)
+			return ret;
+
+		/* You cannot delete a usbg_function directly in an iterator. */
+		goto restart;
+	}
+
+	return 0;
+}
+
+
 static int cfs_reconfigure_gadget(struct usb_client *usb,
 				  struct usb_gadget *gadget)
 {
@@ -827,10 +929,12 @@ static int cfs_reconfigure_gadget(struct usb_client *usb,
 	}
 
 	ret = cfs_cleanup_left_configs(cfs_client, i);
+	if(ret)
+		goto out;
+
+	/* Cleanup things which are left after previous gadget */
+	ret = cfs_cleanup_unused_function(cfs_client->gadget);
 
-	/* TODO
-	 * Cleanup things which are left after previous gadget
-	 */
 out:
 	return ret;
 }