From 17b80976f0aa28842593dae8b05fae9274b51375 Mon Sep 17 00:00:00 2001 From: Andrzej Pietrasiewicz Date: Tue, 28 May 2013 09:15:51 +0200 Subject: [PATCH] usb: gadget: f_eem: add configfs support f_eem learns about our configfs interface so we can remove in-kernel gadget drivers in future. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Kyungmin Park Signed-off-by: Felipe Balbi --- .../ABI/testing/configfs-usb-gadget-eem | 14 ++++++ drivers/usb/gadget/Kconfig | 15 ++++++ drivers/usb/gadget/f_eem.c | 49 +++++++++++++++++++ drivers/usb/gadget/u_eem.h | 9 ++++ 4 files changed, 87 insertions(+) create mode 100644 Documentation/ABI/testing/configfs-usb-gadget-eem diff --git a/Documentation/ABI/testing/configfs-usb-gadget-eem b/Documentation/ABI/testing/configfs-usb-gadget-eem new file mode 100644 index 000000000000..10e87d67fa2e --- /dev/null +++ b/Documentation/ABI/testing/configfs-usb-gadget-eem @@ -0,0 +1,14 @@ +What: /config/usb-gadget/gadget/functions/eem.name +Date: May 2013 +KenelVersion: 3.11 +Description: + The attributes: + + ifname - network device interface name associated with + this function instance + qmult - queue length multiplier for high and + super speed + host_addr - MAC address of host's end of this + Ethernet over USB link + dev_addr - MAC address of device's end of this + Ethernet over USB link diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig index 159393d58912..d5b0ffe26118 100644 --- a/drivers/usb/gadget/Kconfig +++ b/drivers/usb/gadget/Kconfig @@ -544,6 +544,21 @@ choice # this first set of drivers all depend on bulk-capable hardware. +config USB_CONFIGFS_EEM + bool "Ethernet Emulation Model (EEM)" + depends on USB_CONFIGFS + depends on NET + select USB_U_ETHER + select USB_F_EEM + help + CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM + and therefore can be supported by more hardware. Technically ECM and + EEM are designed for different applications. The ECM model extends + the network interface to the target (e.g. a USB cable modem), and the + EEM model is for mobile devices to communicate with hosts using + ethernet over USB. For Linux gadgets, however, the interface with + the host is the same (a usbX device), so the differences are minimal. + config USB_CONFIGFS_PHONET boolean "Phonet protocol" depends on USB_CONFIGFS diff --git a/drivers/usb/gadget/f_eem.c b/drivers/usb/gadget/f_eem.c index 31a2cb7ebe82..90ee8022e8d8 100644 --- a/drivers/usb/gadget/f_eem.c +++ b/drivers/usb/gadget/f_eem.c @@ -19,6 +19,7 @@ #include #include "u_ether.h" +#include "u_ether_configfs.h" #include "u_eem.h" #define EEM_HLEN 2 @@ -263,8 +264,10 @@ static int eem_bind(struct usb_configuration *c, struct usb_function *f) * 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; @@ -533,6 +536,41 @@ error: return status; } +static inline struct f_eem_opts *to_f_eem_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct f_eem_opts, + func_inst.group); +} + +/* f_eem_item_ops */ +USB_ETHERNET_CONFIGFS_ITEM(eem); + +/* f_eem_opts_dev_addr */ +USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(eem); + +/* f_eem_opts_host_addr */ +USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(eem); + +/* f_eem_opts_qmult */ +USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(eem); + +/* f_eem_opts_ifname */ +USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(eem); + +static struct configfs_attribute *eem_attrs[] = { + &f_eem_opts_dev_addr.attr, + &f_eem_opts_host_addr.attr, + &f_eem_opts_qmult.attr, + &f_eem_opts_ifname.attr, + NULL, +}; + +static struct config_item_type eem_func_type = { + .ct_item_ops = &eem_item_ops, + .ct_attrs = eem_attrs, + .ct_owner = THIS_MODULE, +}; + static void eem_free_inst(struct usb_function_instance *f) { struct f_eem_opts *opts; @@ -552,20 +590,28 @@ static struct usb_function_instance *eem_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 = eem_free_inst; opts->net = gether_setup_default(); if (IS_ERR(opts->net)) return ERR_CAST(opts->net); + config_group_init_type_name(&opts->func_inst.group, "", &eem_func_type); + return &opts->func_inst; } static void eem_free(struct usb_function *f) { struct f_eem *eem; + struct f_eem_opts *opts; eem = func_to_eem(f); + opts = container_of(f->fi, struct f_eem_opts, func_inst); kfree(eem); + mutex_lock(&opts->lock); + opts->refcnt--; + mutex_unlock(&opts->lock); } static void eem_unbind(struct usb_configuration *c, struct usb_function *f) @@ -586,8 +632,11 @@ struct usb_function *eem_alloc(struct usb_function_instance *fi) return ERR_PTR(-ENOMEM); opts = container_of(fi, struct f_eem_opts, func_inst); + mutex_lock(&opts->lock); + opts->refcnt++; eem->port.ioport = netdev_priv(opts->net); + mutex_unlock(&opts->lock); eem->port.cdc_filter = DEFAULT_FILTER; eem->port.func.name = "cdc_eem"; diff --git a/drivers/usb/gadget/u_eem.h b/drivers/usb/gadget/u_eem.h index 8f432f2a5e57..e3ae97874c4f 100644 --- a/drivers/usb/gadget/u_eem.h +++ b/drivers/usb/gadget/u_eem.h @@ -22,6 +22,15 @@ struct f_eem_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_EEM_H */