1 files changed, 143 insertions, 41 deletions

diff --git a/drivers/usb/gadget/f_ecm.c b/drivers/usb/gadget/f_ecm.c
index 83420a310fb..798760fa7e7 100644
--- a/drivers/usb/gadget/f_ecm.c
+++ b/drivers/usb/gadget/f_ecm.c
@@ -14,10 +14,13 @@
 
 #include <linux/slab.h>
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/device.h>
 #include <linux/etherdevice.h>
 
 #include "u_ether.h"
+#include "u_ether_configfs.h"
+#include "u_ecm.h"
 
 
 /*
@@ -684,9 +687,43 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct usb_composite_dev *cdev = c->cdev;
 	struct f_ecm		*ecm = func_to_ecm(f);
+	struct usb_string	*us;
 	int			status;
 	struct usb_ep		*ep;
 
+	struct f_ecm_opts	*ecm_opts;
+
+	if (!can_support_ecm(cdev->gadget))
+		return -EINVAL;
+
+	ecm_opts = container_of(f->fi, struct f_ecm_opts, func_inst);
+
+	/*
+	 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
+	 * configurations are bound in sequence with list_for_each_entry,
+	 * in each configuration its functions are bound in sequence
+	 * with list_for_each_entry, so we assume no race condition
+	 * with regard to ecm_opts->bound access
+	 */
+	if (!ecm_opts->bound) {
+		mutex_lock(&ecm_opts->lock);
+		gether_set_gadget(ecm_opts->net, cdev->gadget);
+		status = gether_register_netdev(ecm_opts->net);
+		mutex_unlock(&ecm_opts->lock);
+		if (status)
+			return status;
+		ecm_opts->bound = true;
+	}
+
+	us = usb_gstrings_attach(cdev, ecm_strings,
+				 ARRAY_SIZE(ecm_string_defs));
+	if (IS_ERR(us))
+		return PTR_ERR(us);
+	ecm_control_intf.iInterface = us[0].id;
+	ecm_data_intf.iInterface = us[2].id;
+	ecm_desc.iMACAddress = us[1].id;
+	ecm_iad_descriptor.iFunction = us[3].id;
+
 	/* allocate instance-specific interface IDs */
 	status = usb_interface_id(c, f);
 	if (status < 0)
@@ -796,66 +833,129 @@ fail:
 	return status;
 }
 
-static void
-ecm_unbind(struct usb_configuration *c, struct usb_function *f)
+static inline struct f_ecm_opts *to_f_ecm_opts(struct config_item *item)
+{
+	return container_of(to_config_group(item), struct f_ecm_opts,
+			    func_inst.group);
+}
+
+/* f_ecm_item_ops */
+USB_ETHERNET_CONFIGFS_ITEM(ecm);
+
+/* f_ecm_opts_dev_addr */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ecm);
+
+/* f_ecm_opts_host_addr */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ecm);
+
+/* f_ecm_opts_qmult */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ecm);
+
+/* f_ecm_opts_ifname */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ecm);
+
+static struct configfs_attribute *ecm_attrs[] = {
+	&f_ecm_opts_dev_addr.attr,
+	&f_ecm_opts_host_addr.attr,
+	&f_ecm_opts_qmult.attr,
+	&f_ecm_opts_ifname.attr,
+	NULL,
+};
+
+static struct config_item_type ecm_func_type = {
+	.ct_item_ops	= &ecm_item_ops,
+	.ct_attrs	= ecm_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static void ecm_free_inst(struct usb_function_instance *f)
+{
+	struct f_ecm_opts *opts;
+
+	opts = container_of(f, struct f_ecm_opts, func_inst);
+	if (opts->bound)
+		gether_cleanup(netdev_priv(opts->net));
+	else
+		free_netdev(opts->net);
+	kfree(opts);
+}
+
+static struct usb_function_instance *ecm_alloc_inst(void)
+{
+	struct f_ecm_opts *opts;
+
+	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	if (!opts)
+		return ERR_PTR(-ENOMEM);
+	mutex_init(&opts->lock);
+	opts->func_inst.free_func_inst = ecm_free_inst;
+	opts->net = gether_setup_default();
+	if (IS_ERR(opts->net)) {
+		struct net_device *net = opts->net;
+		kfree(opts);
+		return ERR_CAST(net);
+	}
+
+	config_group_init_type_name(&opts->func_inst.group, "", &ecm_func_type);
+
+	return &opts->func_inst;
+}
+
+static void ecm_free(struct usb_function *f)
+{
+	struct f_ecm *ecm;
+	struct f_ecm_opts *opts;
+
+	ecm = func_to_ecm(f);
+	opts = container_of(f->fi, struct f_ecm_opts, func_inst);
+	kfree(ecm);
+	mutex_lock(&opts->lock);
+	opts->refcnt--;
+	mutex_unlock(&opts->lock);
+}
+
+static void ecm_unbind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct f_ecm		*ecm = func_to_ecm(f);
 
 	DBG(c->cdev, "ecm unbind\n");
 
-	ecm_string_defs[0].id = 0;
 	usb_free_all_descriptors(f);
 
 	kfree(ecm->notify_req->buf);
 	usb_ep_free_request(ecm->notify, ecm->notify_req);
-	kfree(ecm);
 }
 
-/**
- * ecm_bind_config - add CDC Ethernet network link to a configuration
- * @c: the configuration to support the network link
- * @ethaddr: a buffer in which the ethernet address of the host side
- *	side of the link was recorded
- * Context: single threaded during gadget setup
- *
- * Returns zero on success, else negative errno.
- *
- * Caller must have called @gether_setup().  Caller is also responsible
- * for calling @gether_cleanup() before module unload.
- */
-int
-ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
+static struct usb_function *ecm_alloc(struct usb_function_instance *fi)
 {
 	struct f_ecm	*ecm;
-	int		status;
-
-	if (!can_support_ecm(c->cdev->gadget) || !ethaddr)
-		return -EINVAL;
-
-	if (ecm_string_defs[0].id == 0) {
-		status = usb_string_ids_tab(c->cdev, ecm_string_defs);
-		if (status)
-			return status;
-
-		ecm_control_intf.iInterface = ecm_string_defs[0].id;
-		ecm_data_intf.iInterface = ecm_string_defs[2].id;
-		ecm_desc.iMACAddress = ecm_string_defs[1].id;
-		ecm_iad_descriptor.iFunction = ecm_string_defs[3].id;
-	}
+	struct f_ecm_opts *opts;
+	int status;
 
 	/* allocate and initialize one new instance */
-	ecm = kzalloc(sizeof *ecm, GFP_KERNEL);
+	ecm = kzalloc(sizeof(*ecm), GFP_KERNEL);
 	if (!ecm)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
+
+	opts = container_of(fi, struct f_ecm_opts, func_inst);
+	mutex_lock(&opts->lock);
+	opts->refcnt++;
 
 	/* export host's Ethernet address in CDC format */
-	snprintf(ecm->ethaddr, sizeof ecm->ethaddr, "%pm", ethaddr);
+	status = gether_get_host_addr_cdc(opts->net, ecm->ethaddr,
+					  sizeof(ecm->ethaddr));
+	if (status < 12) {
+		kfree(ecm);
+		mutex_unlock(&opts->lock);
+		return ERR_PTR(-EINVAL);
+	}
 	ecm_string_defs[1].s = ecm->ethaddr;
 
+	ecm->port.ioport = netdev_priv(opts->net);
+	mutex_unlock(&opts->lock);
 	ecm->port.cdc_filter = DEFAULT_FILTER;
 
 	ecm->port.func.name = "cdc_ethernet";
-	ecm->port.func.strings = ecm_strings;
 	/* descriptors are per-instance copies */
 	ecm->port.func.bind = ecm_bind;
 	ecm->port.func.unbind = ecm_unbind;
@@ -863,9 +963,11 @@ ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
 	ecm->port.func.get_alt = ecm_get_alt;
 	ecm->port.func.setup = ecm_setup;
 	ecm->port.func.disable = ecm_disable;
+	ecm->port.func.free_func = ecm_free;
 
-	status = usb_add_function(c, &ecm->port.func);
-	if (status)
-		kfree(ecm);
-	return status;
+	return &ecm->port.func;
 }
+
+DECLARE_USB_FUNCTION_INIT(ecm, ecm_alloc_inst, ecm_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Brownell");