X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fusb%2Fgadget%2Ffunction%2Ff_eem.c;fp=kernel%2Fdrivers%2Fusb%2Fgadget%2Ffunction%2Ff_eem.c;h=c9e90de5bdd9192c459dd3dea7a9aafa3c086c6b;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git diff --git a/kernel/drivers/usb/gadget/function/f_eem.c b/kernel/drivers/usb/gadget/function/f_eem.c new file mode 100644 index 000000000..c9e90de5b --- /dev/null +++ b/kernel/drivers/usb/gadget/function/f_eem.c @@ -0,0 +1,659 @@ +/* + * f_eem.c -- USB CDC Ethernet (EEM) link function driver + * + * Copyright (C) 2003-2005,2008 David Brownell + * Copyright (C) 2008 Nokia Corporation + * Copyright (C) 2009 EF Johnson Technologies + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include + +#include "u_ether.h" +#include "u_ether_configfs.h" +#include "u_eem.h" + +#define EEM_HLEN 2 + +/* + * This function is a "CDC Ethernet Emulation Model" (CDC EEM) + * Ethernet link. + */ + +struct f_eem { + struct gether port; + u8 ctrl_id; +}; + +static inline struct f_eem *func_to_eem(struct usb_function *f) +{ + return container_of(f, struct f_eem, port.func); +} + +/*-------------------------------------------------------------------------*/ + +/* interface descriptor: */ + +static struct usb_interface_descriptor eem_intf = { + .bLength = sizeof eem_intf, + .bDescriptorType = USB_DT_INTERFACE, + + /* .bInterfaceNumber = DYNAMIC */ + .bNumEndpoints = 2, + .bInterfaceClass = USB_CLASS_COMM, + .bInterfaceSubClass = USB_CDC_SUBCLASS_EEM, + .bInterfaceProtocol = USB_CDC_PROTO_EEM, + /* .iInterface = DYNAMIC */ +}; + +/* full speed support: */ + +static struct usb_endpoint_descriptor eem_fs_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_endpoint_descriptor eem_fs_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_descriptor_header *eem_fs_function[] = { + /* CDC EEM control descriptors */ + (struct usb_descriptor_header *) &eem_intf, + (struct usb_descriptor_header *) &eem_fs_in_desc, + (struct usb_descriptor_header *) &eem_fs_out_desc, + NULL, +}; + +/* high speed support: */ + +static struct usb_endpoint_descriptor eem_hs_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512), +}; + +static struct usb_endpoint_descriptor eem_hs_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512), +}; + +static struct usb_descriptor_header *eem_hs_function[] = { + /* CDC EEM control descriptors */ + (struct usb_descriptor_header *) &eem_intf, + (struct usb_descriptor_header *) &eem_hs_in_desc, + (struct usb_descriptor_header *) &eem_hs_out_desc, + NULL, +}; + +/* super speed support: */ + +static struct usb_endpoint_descriptor eem_ss_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_endpoint_descriptor eem_ss_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_ss_ep_comp_descriptor eem_ss_bulk_comp_desc = { + .bLength = sizeof eem_ss_bulk_comp_desc, + .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, + + /* the following 2 values can be tweaked if necessary */ + /* .bMaxBurst = 0, */ + /* .bmAttributes = 0, */ +}; + +static struct usb_descriptor_header *eem_ss_function[] = { + /* CDC EEM control descriptors */ + (struct usb_descriptor_header *) &eem_intf, + (struct usb_descriptor_header *) &eem_ss_in_desc, + (struct usb_descriptor_header *) &eem_ss_bulk_comp_desc, + (struct usb_descriptor_header *) &eem_ss_out_desc, + (struct usb_descriptor_header *) &eem_ss_bulk_comp_desc, + NULL, +}; + +/* string descriptors: */ + +static struct usb_string eem_string_defs[] = { + [0].s = "CDC Ethernet Emulation Model (EEM)", + { } /* end of list */ +}; + +static struct usb_gadget_strings eem_string_table = { + .language = 0x0409, /* en-us */ + .strings = eem_string_defs, +}; + +static struct usb_gadget_strings *eem_strings[] = { + &eem_string_table, + NULL, +}; + +/*-------------------------------------------------------------------------*/ + +static int eem_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) +{ + struct usb_composite_dev *cdev = f->config->cdev; + int value = -EOPNOTSUPP; + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + u16 w_length = le16_to_cpu(ctrl->wLength); + + DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n", + ctrl->bRequestType, ctrl->bRequest, + w_value, w_index, w_length); + + /* device either stalls (value < 0) or reports success */ + return value; +} + + +static int eem_set_alt(struct usb_function *f, unsigned intf, unsigned alt) +{ + struct f_eem *eem = func_to_eem(f); + struct usb_composite_dev *cdev = f->config->cdev; + struct net_device *net; + + /* we know alt == 0, so this is an activation or a reset */ + if (alt != 0) + goto fail; + + if (intf == eem->ctrl_id) { + + if (eem->port.in_ep->driver_data) { + DBG(cdev, "reset eem\n"); + gether_disconnect(&eem->port); + } + + if (!eem->port.in_ep->desc || !eem->port.out_ep->desc) { + DBG(cdev, "init eem\n"); + if (config_ep_by_speed(cdev->gadget, f, + eem->port.in_ep) || + config_ep_by_speed(cdev->gadget, f, + eem->port.out_ep)) { + eem->port.in_ep->desc = NULL; + eem->port.out_ep->desc = NULL; + goto fail; + } + } + + /* zlps should not occur because zero-length EEM packets + * will be inserted in those cases where they would occur + */ + eem->port.is_zlp_ok = 1; + eem->port.cdc_filter = DEFAULT_FILTER; + DBG(cdev, "activate eem\n"); + net = gether_connect(&eem->port); + if (IS_ERR(net)) + return PTR_ERR(net); + } else + goto fail; + + return 0; +fail: + return -EINVAL; +} + +static void eem_disable(struct usb_function *f) +{ + struct f_eem *eem = func_to_eem(f); + struct usb_composite_dev *cdev = f->config->cdev; + + DBG(cdev, "eem deactivated\n"); + + if (eem->port.in_ep->driver_data) + gether_disconnect(&eem->port); +} + +/*-------------------------------------------------------------------------*/ + +/* EEM function driver setup/binding */ + +static int eem_bind(struct usb_configuration *c, struct usb_function *f) +{ + struct usb_composite_dev *cdev = c->cdev; + struct f_eem *eem = func_to_eem(f); + struct usb_string *us; + int status; + struct usb_ep *ep; + + struct f_eem_opts *eem_opts; + + 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; + } + + us = usb_gstrings_attach(cdev, eem_strings, + ARRAY_SIZE(eem_string_defs)); + if (IS_ERR(us)) + return PTR_ERR(us); + eem_intf.iInterface = us[0].id; + + /* allocate instance-specific interface IDs */ + status = usb_interface_id(c, f); + if (status < 0) + goto fail; + 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; + eem->port.in_ep = ep; + ep->driver_data = cdev; /* claim */ + + ep = usb_ep_autoconfig(cdev->gadget, &eem_fs_out_desc); + if (!ep) + goto fail; + eem->port.out_ep = ep; + ep->driver_data = cdev; /* claim */ + + status = -ENOMEM; + + /* support all relevant hardware speeds... we expect that when + * hardware is dual speed, all bulk-capable endpoints work at + * both speeds + */ + eem_hs_in_desc.bEndpointAddress = eem_fs_in_desc.bEndpointAddress; + eem_hs_out_desc.bEndpointAddress = eem_fs_out_desc.bEndpointAddress; + + eem_ss_in_desc.bEndpointAddress = eem_fs_in_desc.bEndpointAddress; + eem_ss_out_desc.bEndpointAddress = eem_fs_out_desc.bEndpointAddress; + + status = usb_assign_descriptors(f, eem_fs_function, eem_hs_function, + eem_ss_function); + if (status) + goto fail; + + DBG(cdev, "CDC Ethernet (EEM): %s speed IN/%s OUT/%s\n", + gadget_is_superspeed(c->cdev->gadget) ? "super" : + gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", + eem->port.in_ep->name, eem->port.out_ep->name); + return 0; + +fail: + if (eem->port.out_ep) + eem->port.out_ep->driver_data = NULL; + if (eem->port.in_ep) + eem->port.in_ep->driver_data = NULL; + + 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) +{ + struct sk_buff *skb = (struct sk_buff *)req->context; + + dev_kfree_skb_any(skb); +} + +/* + * Add the EEM header and ethernet checksum. + * We currently do not attempt to put multiple ethernet frames + * into a single USB transfer + */ +static struct sk_buff *eem_wrap(struct gether *port, struct sk_buff *skb) +{ + struct sk_buff *skb2 = NULL; + struct usb_ep *in = port->in_ep; + int padlen = 0; + u16 len = skb->len; + + int headroom = skb_headroom(skb); + int tailroom = skb_tailroom(skb); + + /* When (len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) is 0, + * stick two bytes of zero-length EEM packet on the end. + */ + if (((len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) == 0) + padlen += 2; + + if ((tailroom >= (ETH_FCS_LEN + padlen)) && + (headroom >= EEM_HLEN) && !skb_cloned(skb)) + goto done; + + skb2 = skb_copy_expand(skb, EEM_HLEN, ETH_FCS_LEN + padlen, GFP_ATOMIC); + dev_kfree_skb_any(skb); + skb = skb2; + if (!skb) + return skb; + +done: + /* use the "no CRC" option */ + put_unaligned_be32(0xdeadbeef, skb_put(skb, 4)); + + /* EEM packet header format: + * b0..13: length of ethernet frame + * b14: bmCRC (0 == sentinel CRC) + * b15: bmType (0 == data) + */ + len = skb->len; + put_unaligned_le16(len & 0x3FFF, skb_push(skb, 2)); + + /* add a zero-length EEM packet, if needed */ + if (padlen) + put_unaligned_le16(0, skb_put(skb, 2)); + + return skb; +} + +/* + * Remove the EEM header. Note that there can be many EEM packets in a single + * USB transfer, so we need to break them out and handle them independently. + */ +static int eem_unwrap(struct gether *port, + struct sk_buff *skb, + struct sk_buff_head *list) +{ + struct usb_composite_dev *cdev = port->func.config->cdev; + int status = 0; + + do { + struct sk_buff *skb2; + u16 header; + u16 len = 0; + + if (skb->len < EEM_HLEN) { + status = -EINVAL; + DBG(cdev, "invalid EEM header\n"); + goto error; + } + + /* remove the EEM header */ + header = get_unaligned_le16(skb->data); + skb_pull(skb, EEM_HLEN); + + /* EEM packet header format: + * b0..14: EEM type dependent (data or command) + * b15: bmType (0 == data, 1 == command) + */ + if (header & BIT(15)) { + struct usb_request *req = cdev->req; + u16 bmEEMCmd; + + /* EEM command packet format: + * b0..10: bmEEMCmdParam + * b11..13: bmEEMCmd + * b14: reserved (must be zero) + * b15: bmType (1 == command) + */ + if (header & BIT(14)) + continue; + + bmEEMCmd = (header >> 11) & 0x7; + switch (bmEEMCmd) { + case 0: /* echo */ + len = header & 0x7FF; + if (skb->len < len) { + status = -EOVERFLOW; + goto error; + } + + skb2 = skb_clone(skb, GFP_ATOMIC); + if (unlikely(!skb2)) { + DBG(cdev, "EEM echo response error\n"); + goto next; + } + skb_trim(skb2, len); + put_unaligned_le16(BIT(15) | BIT(11) | len, + skb_push(skb2, 2)); + skb_copy_bits(skb2, 0, req->buf, skb2->len); + req->length = skb2->len; + req->complete = eem_cmd_complete; + req->zero = 1; + req->context = skb2; + if (usb_ep_queue(port->in_ep, req, GFP_ATOMIC)) + DBG(cdev, "echo response queue fail\n"); + break; + + case 1: /* echo response */ + case 2: /* suspend hint */ + case 3: /* response hint */ + case 4: /* response complete hint */ + case 5: /* tickle */ + default: /* reserved */ + continue; + } + } else { + u32 crc, crc2; + struct sk_buff *skb3; + + /* check for zero-length EEM packet */ + if (header == 0) + continue; + + /* EEM data packet format: + * b0..13: length of ethernet frame + * b14: bmCRC (0 == sentinel, 1 == calculated) + * b15: bmType (0 == data) + */ + len = header & 0x3FFF; + if ((skb->len < len) + || (len < (ETH_HLEN + ETH_FCS_LEN))) { + status = -EINVAL; + goto error; + } + + /* validate CRC */ + if (header & BIT(14)) { + crc = get_unaligned_le32(skb->data + len + - ETH_FCS_LEN); + crc2 = ~crc32_le(~0, + skb->data, len - ETH_FCS_LEN); + } else { + crc = get_unaligned_be32(skb->data + len + - ETH_FCS_LEN); + crc2 = 0xdeadbeef; + } + if (crc != crc2) { + DBG(cdev, "invalid EEM CRC\n"); + goto next; + } + + skb2 = skb_clone(skb, GFP_ATOMIC); + if (unlikely(!skb2)) { + DBG(cdev, "unable to unframe EEM packet\n"); + continue; + } + skb_trim(skb2, len - ETH_FCS_LEN); + + skb3 = skb_copy_expand(skb2, + NET_IP_ALIGN, + 0, + GFP_ATOMIC); + if (unlikely(!skb3)) { + DBG(cdev, "unable to realign EEM packet\n"); + dev_kfree_skb_any(skb2); + continue; + } + dev_kfree_skb_any(skb2); + skb_queue_tail(list, skb3); + } +next: + skb_pull(skb, len); + } while (skb->len); + +error: + dev_kfree_skb_any(skb); + 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; + + opts = container_of(f, struct f_eem_opts, func_inst); + if (opts->bound) + gether_cleanup(netdev_priv(opts->net)); + else + free_netdev(opts->net); + kfree(opts); +} + +static struct usb_function_instance *eem_alloc_inst(void) +{ + struct f_eem_opts *opts; + + 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)) { + struct net_device *net = opts->net; + kfree(opts); + return ERR_CAST(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) +{ + DBG(c->cdev, "eem unbind\n"); + + usb_free_all_descriptors(f); +} + +static struct usb_function *eem_alloc(struct usb_function_instance *fi) +{ + struct f_eem *eem; + struct f_eem_opts *opts; + + /* allocate and initialize one new instance */ + eem = kzalloc(sizeof(*eem), GFP_KERNEL); + if (!eem) + 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"; + /* descriptors are per-instance copies */ + eem->port.func.bind = eem_bind; + eem->port.func.unbind = eem_unbind; + eem->port.func.set_alt = eem_set_alt; + eem->port.func.setup = eem_setup; + eem->port.func.disable = eem_disable; + eem->port.func.free_func = eem_free; + eem->port.wrap = eem_wrap; + eem->port.unwrap = eem_unwrap; + eem->port.header_len = EEM_HLEN; + + return &eem->port.func; +} + +DECLARE_USB_FUNCTION_INIT(eem, eem_alloc_inst, eem_alloc); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("David Brownell");