diff options
Diffstat (limited to 'drivers/usb/gadget/function')
| -rw-r--r-- | drivers/usb/gadget/function/f_eem.c | 59 | ||||
| -rw-r--r-- | drivers/usb/gadget/function/u_eem.h | 21 |
2 files changed, 46 insertions, 34 deletions
diff --git a/drivers/usb/gadget/function/f_eem.c b/drivers/usb/gadget/function/f_eem.c index edbbadad6138..36f4295e6d63 100644 --- a/drivers/usb/gadget/function/f_eem.c +++ b/drivers/usb/gadget/function/f_eem.c @@ -7,6 +7,7 @@ * Copyright (C) 2009 EF Johnson Technologies */ +#include <linux/cleanup.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/device.h> @@ -251,24 +252,22 @@ static int eem_bind(struct usb_configuration *c, struct usb_function *f) struct usb_ep *ep; struct f_eem_opts *eem_opts; + struct net_device *net __free(detach_gadget) = NULL; eem_opts = container_of(f->fi, struct f_eem_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 eem_opts->bound access - */ - if (!eem_opts->bound) { - mutex_lock(&eem_opts->lock); - gether_set_gadget(eem_opts->net, cdev->gadget); - status = gether_register_netdev(eem_opts->net); - mutex_unlock(&eem_opts->lock); - if (status) - return status; - eem_opts->bound = true; - } + + scoped_guard(mutex, &eem_opts->lock) + if (eem_opts->bind_count == 0 && !eem_opts->bound) { + if (!device_is_registered(&eem_opts->net->dev)) { + gether_set_gadget(eem_opts->net, cdev->gadget); + status = gether_register_netdev(eem_opts->net); + } else + status = gether_attach_gadget(eem_opts->net, cdev->gadget); + + if (status) + return status; + net = eem_opts->net; + } us = usb_gstrings_attach(cdev, eem_strings, ARRAY_SIZE(eem_string_defs)); @@ -279,21 +278,19 @@ static int eem_bind(struct usb_configuration *c, struct usb_function *f) /* allocate instance-specific interface IDs */ status = usb_interface_id(c, f); if (status < 0) - goto fail; + return status; eem->ctrl_id = status; eem_intf.bInterfaceNumber = status; - status = -ENODEV; - /* allocate instance-specific endpoints */ ep = usb_ep_autoconfig(cdev->gadget, &eem_fs_in_desc); if (!ep) - goto fail; + return -ENODEV; eem->port.in_ep = ep; ep = usb_ep_autoconfig(cdev->gadget, &eem_fs_out_desc); if (!ep) - goto fail; + return -ENODEV; eem->port.out_ep = ep; /* support all relevant hardware speeds... we expect that when @@ -309,16 +306,14 @@ static int eem_bind(struct usb_configuration *c, struct usb_function *f) status = usb_assign_descriptors(f, eem_fs_function, eem_hs_function, eem_ss_function, eem_ss_function); if (status) - goto fail; + return status; + + eem_opts->bind_count++; + retain_and_null_ptr(net); DBG(cdev, "CDC Ethernet (EEM): IN/%s OUT/%s\n", eem->port.in_ep->name, eem->port.out_ep->name); return 0; - -fail: - ERROR(cdev, "%s: can't bind, err %d\n", f->name, status); - - return status; } static void eem_cmd_complete(struct usb_ep *ep, struct usb_request *req) @@ -597,7 +592,7 @@ static void eem_free_inst(struct usb_function_instance *f) struct f_eem_opts *opts; opts = container_of(f, struct f_eem_opts, func_inst); - if (opts->bound) + if (device_is_registered(&opts->net->dev)) gether_cleanup(netdev_priv(opts->net)); else free_netdev(opts->net); @@ -640,9 +635,17 @@ static void eem_free(struct usb_function *f) static void eem_unbind(struct usb_configuration *c, struct usb_function *f) { + struct f_eem_opts *opts; + DBG(c->cdev, "eem unbind\n"); + opts = container_of(f->fi, struct f_eem_opts, func_inst); + usb_free_all_descriptors(f); + + opts->bind_count--; + if (opts->bind_count == 0 && !opts->bound) + gether_detach_gadget(opts->net); } static struct usb_function *eem_alloc(struct usb_function_instance *fi) diff --git a/drivers/usb/gadget/function/u_eem.h b/drivers/usb/gadget/function/u_eem.h index 3bd85dfcd71c..78ef55815219 100644 --- a/drivers/usb/gadget/function/u_eem.h +++ b/drivers/usb/gadget/function/u_eem.h @@ -15,17 +15,26 @@ #include <linux/usb/composite.h> +/** + * struct f_eem_opts - EEM function options + * @func_inst: USB function instance. + * @net: The net_device associated with the EEM function. + * @bound: True if the net_device is shared and pre-registered during the + * legacy composite driver's bind phase (e.g., multi.c). If false, + * the EEM function will register the net_device during its own + * bind phase. + * @bind_count: Tracks the number of configurations the EEM function is + * bound to, preventing double-registration of the @net device. + * @lock: Protects the data from concurrent access by configfs read/write + * and create symlink/remove symlink operations. + * @refcnt: Reference counter for the function instance. + */ struct f_eem_opts { struct usb_function_instance func_inst; struct net_device *net; bool bound; + int bind_count; - /* - * Read/write access to configfs attributes is handled by configfs. - * - * This is to protect the data from concurrent access by read/write - * and create symlink/remove symlink. - */ struct mutex lock; int refcnt; }; |