From e730660378be92b83288b59b824ccdace5cd2652 Mon Sep 17 00:00:00 2001 From: Andrzej Pietrasiewicz Date: Thu, 23 May 2013 09:22:10 +0200 Subject: [PATCH] usb: gadget: f_ncm: add configfs support Add configfs support to the NCM function driver so that we can, eventually, get rid of kernel-based gadget drivers. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Kyungmin Park Signed-off-by: Felipe Balbi --- drivers/usb/gadget/f_ncm.c | 166 +++++++++++++++++++++++++++++++++++++ drivers/usb/gadget/u_ncm.h | 9 ++ 2 files changed, 175 insertions(+) diff --git a/drivers/usb/gadget/f_ncm.c b/drivers/usb/gadget/f_ncm.c index effd2fada925..697262e2a575 100644 --- a/drivers/usb/gadget/f_ncm.c +++ b/drivers/usb/gadget/f_ncm.c @@ -1175,8 +1175,10 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f) * with regard to ncm_opts->bound access */ if (!ncm_opts->bound) { + mutex_lock(&ncm_opts->lock); gether_set_gadget(ncm_opts->net, cdev->gadget); status = gether_register_netdev(ncm_opts->net); + mutex_unlock(&ncm_opts->lock); if (status) return status; ncm_opts->bound = true; @@ -1290,6 +1292,159 @@ fail: return status; } +static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct f_ncm_opts, + func_inst.group); +} + +CONFIGFS_ATTR_STRUCT(f_ncm_opts); +CONFIGFS_ATTR_OPS(f_ncm_opts); + +static void ncm_attr_release(struct config_item *item) +{ + struct f_ncm_opts *opts = to_f_ncm_opts(item); + + usb_put_function_instance(&opts->func_inst); +} + +static struct configfs_item_operations ncm_item_ops = { + .release = ncm_attr_release, + .show_attribute = f_ncm_opts_attr_show, + .store_attribute = f_ncm_opts_attr_store, +}; + +static ssize_t ncm_opts_dev_addr_show(struct f_ncm_opts *opts, char *page) +{ + int result; + + mutex_lock(&opts->lock); + result = gether_get_dev_addr(opts->net, page, PAGE_SIZE); + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t ncm_opts_dev_addr_store(struct f_ncm_opts *opts, + const char *page, size_t len) +{ + int ret; + + mutex_lock(&opts->lock); + if (opts->refcnt) { + mutex_unlock(&opts->lock); + return -EBUSY; + } + + ret = gether_set_dev_addr(opts->net, page); + mutex_unlock(&opts->lock); + if (!ret) + ret = len; + return ret; +} + +static struct f_ncm_opts_attribute f_ncm_opts_dev_addr = + __CONFIGFS_ATTR(dev_addr, S_IRUGO | S_IWUSR, ncm_opts_dev_addr_show, + ncm_opts_dev_addr_store); + +static ssize_t ncm_opts_host_addr_show(struct f_ncm_opts *opts, char *page) +{ + int result; + + mutex_lock(&opts->lock); + result = gether_get_host_addr(opts->net, page, PAGE_SIZE); + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t ncm_opts_host_addr_store(struct f_ncm_opts *opts, + const char *page, size_t len) +{ + int ret; + + mutex_lock(&opts->lock); + if (opts->refcnt) { + mutex_unlock(&opts->lock); + return -EBUSY; + } + + ret = gether_set_host_addr(opts->net, page); + mutex_unlock(&opts->lock); + if (!ret) + ret = len; + return ret; +} + +static struct f_ncm_opts_attribute f_ncm_opts_host_addr = + __CONFIGFS_ATTR(host_addr, S_IRUGO | S_IWUSR, ncm_opts_host_addr_show, + ncm_opts_host_addr_store); + +static ssize_t ncm_opts_qmult_show(struct f_ncm_opts *opts, char *page) +{ + unsigned qmult; + + mutex_lock(&opts->lock); + qmult = gether_get_qmult(opts->net); + mutex_unlock(&opts->lock); + return sprintf(page, "%d", qmult); +} + +static ssize_t ncm_opts_qmult_store(struct f_ncm_opts *opts, + const char *page, size_t len) +{ + u8 val; + int ret; + + mutex_lock(&opts->lock); + if (opts->refcnt) { + ret = -EBUSY; + goto out; + } + + ret = kstrtou8(page, 0, &val); + if (ret) + goto out; + + gether_set_qmult(opts->net, val); + ret = len; +out: + mutex_unlock(&opts->lock); + return ret; +} + +static struct f_ncm_opts_attribute f_ncm_opts_qmult = + __CONFIGFS_ATTR(qmult, S_IRUGO | S_IWUSR, ncm_opts_qmult_show, + ncm_opts_qmult_store); + +static ssize_t ncm_opts_ifname_show(struct f_ncm_opts *opts, char *page) +{ + int ret; + + mutex_lock(&opts->lock); + ret = gether_get_ifname(opts->net, page, PAGE_SIZE); + mutex_unlock(&opts->lock); + + return ret; +} + +static struct f_ncm_opts_attribute f_ncm_opts_ifname = + __CONFIGFS_ATTR_RO(ifname, ncm_opts_ifname_show); + +static struct configfs_attribute *ncm_attrs[] = { + &f_ncm_opts_dev_addr.attr, + &f_ncm_opts_host_addr.attr, + &f_ncm_opts_qmult.attr, + &f_ncm_opts_ifname.attr, + NULL, +}; + +static struct config_item_type ncm_func_type = { + .ct_item_ops = &ncm_item_ops, + .ct_attrs = ncm_attrs, + .ct_owner = THIS_MODULE, +}; + static void ncm_free_inst(struct usb_function_instance *f) { struct f_ncm_opts *opts; @@ -1309,20 +1464,28 @@ static struct usb_function_instance *ncm_alloc_inst(void) opts = kzalloc(sizeof(*opts), GFP_KERNEL); if (!opts) return ERR_PTR(-ENOMEM); + mutex_init(&opts->lock); opts->func_inst.free_func_inst = ncm_free_inst; opts->net = gether_setup_default(); if (IS_ERR(opts->net)) return ERR_PTR(PTR_ERR(opts->net)); + config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type); + return &opts->func_inst; } static void ncm_free(struct usb_function *f) { struct f_ncm *ncm; + struct f_ncm_opts *opts; ncm = func_to_ncm(f); + opts = container_of(f->fi, struct f_ncm_opts, func_inst); kfree(ncm); + mutex_lock(&opts->lock); + opts->refcnt--; + mutex_unlock(&opts->lock); } static void ncm_unbind(struct usb_configuration *c, struct usb_function *f) @@ -1349,6 +1512,8 @@ struct usb_function *ncm_alloc(struct usb_function_instance *fi) return ERR_PTR(-ENOMEM); opts = container_of(fi, struct f_ncm_opts, func_inst); + mutex_lock(&opts->lock); + opts->refcnt++; /* export host's Ethernet address in CDC format */ status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr, @@ -1362,6 +1527,7 @@ struct usb_function *ncm_alloc(struct usb_function_instance *fi) spin_lock_init(&ncm->lock); ncm_reset_values(ncm); ncm->port.ioport = netdev_priv(opts->net); + mutex_unlock(&opts->lock); ncm->port.is_fixed = true; ncm->port.func.name = "cdc_network"; diff --git a/drivers/usb/gadget/u_ncm.h b/drivers/usb/gadget/u_ncm.h index 1e22b5fa844b..ce0f3a78ca13 100644 --- a/drivers/usb/gadget/u_ncm.h +++ b/drivers/usb/gadget/u_ncm.h @@ -22,6 +22,15 @@ struct f_ncm_opts { struct usb_function_instance func_inst; struct net_device *net; bool bound; + + /* + * 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; }; #endif /* U_NCM_H */