diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/usb/cdc_mbim.c | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c new file mode 100644 index 00000000000..2f21139466e --- /dev/null +++ b/drivers/net/usb/cdc_mbim.c @@ -0,0 +1,365 @@ +/* + * Copyright (c) 2012 Smith Micro Software, Inc. + * Copyright (c) 2012 Bjørn Mork <bjorn@mork.no> + * + * This driver is based on and reuse most of cdc_ncm, which is + * Copyright (C) ST-Ericsson 2010-2012 + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/ethtool.h> +#include <linux/ip.h> +#include <linux/mii.h> +#include <linux/usb.h> +#include <linux/usb/cdc.h> +#include <linux/usb/usbnet.h> +#include <linux/usb/cdc-wdm.h> +#include <linux/usb/cdc_ncm.h> + +/* driver specific data - must match cdc_ncm usage */ +struct cdc_mbim_state { + struct cdc_ncm_ctx *ctx; + atomic_t pmcount; + struct usb_driver *subdriver; + struct usb_interface *control; + struct usb_interface *data; +}; + +/* using a counter to merge subdriver requests with our own into a combined state */ +static int cdc_mbim_manage_power(struct usbnet *dev, int on) +{ + struct cdc_mbim_state *info = (void *)&dev->data; + int rv = 0; + + dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on); + + if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) { + /* need autopm_get/put here to ensure the usbcore sees the new value */ + rv = usb_autopm_get_interface(dev->intf); + if (rv < 0) + goto err; + dev->intf->needs_remote_wakeup = on; + usb_autopm_put_interface(dev->intf); + } +err: + return rv; +} + +static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status) +{ + struct usbnet *dev = usb_get_intfdata(intf); + + /* can be called while disconnecting */ + if (!dev) + return 0; + + return cdc_mbim_manage_power(dev, status); +} + + +static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf) +{ + struct cdc_ncm_ctx *ctx; + struct usb_driver *subdriver = ERR_PTR(-ENODEV); + int ret = -ENODEV; + u8 data_altsetting = CDC_NCM_DATA_ALTSETTING_NCM; + struct cdc_mbim_state *info = (void *)&dev->data; + + /* see if interface supports MBIM alternate setting */ + if (intf->num_altsetting == 2) { + if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) + usb_set_interface(dev->udev, + intf->cur_altsetting->desc.bInterfaceNumber, + CDC_NCM_COMM_ALTSETTING_MBIM); + data_altsetting = CDC_NCM_DATA_ALTSETTING_MBIM; + } + + /* Probably NCM, defer for cdc_ncm_bind */ + if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) + goto err; + + ret = cdc_ncm_bind_common(dev, intf, data_altsetting); + if (ret) + goto err; + + ctx = info->ctx; + + /* The MBIM descriptor and the status endpoint are required */ + if (ctx->mbim_desc && dev->status) + subdriver = usb_cdc_wdm_register(ctx->control, + &dev->status->desc, + le16_to_cpu(ctx->mbim_desc->wMaxControlMessage), + cdc_mbim_wdm_manage_power); + if (IS_ERR(subdriver)) { + ret = PTR_ERR(subdriver); + cdc_ncm_unbind(dev, intf); + goto err; + } + + /* can't let usbnet use the interrupt endpoint */ + dev->status = NULL; + info->subdriver = subdriver; + + /* MBIM cannot do ARP */ + dev->net->flags |= IFF_NOARP; +err: + return ret; +} + +static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf) +{ + struct cdc_mbim_state *info = (void *)&dev->data; + struct cdc_ncm_ctx *ctx = info->ctx; + + /* disconnect subdriver from control interface */ + if (info->subdriver && info->subdriver->disconnect) + info->subdriver->disconnect(ctx->control); + info->subdriver = NULL; + + /* let NCM unbind clean up both control and data interface */ + cdc_ncm_unbind(dev, intf); +} + + +static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) +{ + struct sk_buff *skb_out; + struct cdc_mbim_state *info = (void *)&dev->data; + struct cdc_ncm_ctx *ctx = info->ctx; + + if (!ctx) + goto error; + + if (skb) { + if (skb->len <= sizeof(ETH_HLEN)) + goto error; + + skb_reset_mac_header(skb); + switch (eth_hdr(skb)->h_proto) { + case htons(ETH_P_IP): + case htons(ETH_P_IPV6): + skb_pull(skb, ETH_HLEN); + break; + default: + goto error; + } + } + + spin_lock_bh(&ctx->mtx); + skb_out = cdc_ncm_fill_tx_frame(ctx, skb, cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN)); + spin_unlock_bh(&ctx->mtx); + return skb_out; + +error: + if (skb) + dev_kfree_skb_any(skb); + + return NULL; +} + +static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len) +{ + __be16 proto; + struct sk_buff *skb = NULL; + + switch (*buf & 0xf0) { + case 0x40: + proto = htons(ETH_P_IP); + break; + case 0x60: + proto = htons(ETH_P_IPV6); + break; + default: + goto err; + } + + skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN); + if (!skb) + goto err; + + /* add an ethernet header */ + skb_put(skb, ETH_HLEN); + skb_reset_mac_header(skb); + eth_hdr(skb)->h_proto = proto; + memset(eth_hdr(skb)->h_source, 0, ETH_ALEN); + memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN); + + /* add datagram */ + memcpy(skb_put(skb, len), buf, len); +err: + return skb; +} + +static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in) +{ + struct sk_buff *skb; + struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; + int len; + int nframes; + int x; + int offset; + struct usb_cdc_ncm_ndp16 *ndp16; + struct usb_cdc_ncm_dpe16 *dpe16; + int ndpoffset; + int loopcount = 50; /* arbitrary max preventing infinite loop */ + + ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in); + if (ndpoffset < 0) + goto error; + +next_ndp: + nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset); + if (nframes < 0) + goto error; + + ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset); + + /* only supporting IPS Session #0 for now */ + switch (ndp16->dwSignature) { + case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN): + break; + default: + netif_dbg(dev, rx_err, dev->net, + "unsupported NDP signature <0x%08x>\n", + le32_to_cpu(ndp16->dwSignature)); + goto err_ndp; + + } + + dpe16 = ndp16->dpe16; + for (x = 0; x < nframes; x++, dpe16++) { + offset = le16_to_cpu(dpe16->wDatagramIndex); + len = le16_to_cpu(dpe16->wDatagramLength); + + /* + * CDC NCM ch. 3.7 + * All entries after first NULL entry are to be ignored + */ + if ((offset == 0) || (len == 0)) { + if (!x) + goto err_ndp; /* empty NTB */ + break; + } + + /* sanity checking */ + if (((offset + len) > skb_in->len) || (len > ctx->rx_max) || + (len < sizeof(struct iphdr))) { + netif_dbg(dev, rx_err, dev->net, + "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n", + x, offset, len, skb_in); + if (!x) + goto err_ndp; + break; + } else { + skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len); + if (!skb) + goto error; + usbnet_skb_return(dev, skb); + } + } +err_ndp: + /* are there more NDPs to process? */ + ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex); + if (ndpoffset && loopcount--) + goto next_ndp; + + return 1; +error: + return 0; +} + +static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message) +{ + int ret = 0; + struct usbnet *dev = usb_get_intfdata(intf); + struct cdc_mbim_state *info = (void *)&dev->data; + struct cdc_ncm_ctx *ctx = info->ctx; + + if (ctx == NULL) { + ret = -1; + goto error; + } + + ret = usbnet_suspend(intf, message); + if (ret < 0) + goto error; + + if (intf == ctx->control && info->subdriver && info->subdriver->suspend) + ret = info->subdriver->suspend(intf, message); + if (ret < 0) + usbnet_resume(intf); + +error: + return ret; +} + +static int cdc_mbim_resume(struct usb_interface *intf) +{ + int ret = 0; + struct usbnet *dev = usb_get_intfdata(intf); + struct cdc_mbim_state *info = (void *)&dev->data; + struct cdc_ncm_ctx *ctx = info->ctx; + bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume); + + if (callsub) + ret = info->subdriver->resume(intf); + if (ret < 0) + goto err; + ret = usbnet_resume(intf); + if (ret < 0 && callsub && info->subdriver->suspend) + info->subdriver->suspend(intf, PMSG_SUSPEND); +err: + return ret; +} + +static const struct driver_info cdc_mbim_info = { + .description = "CDC MBIM", + .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN, + .bind = cdc_mbim_bind, + .unbind = cdc_mbim_unbind, + .manage_power = cdc_mbim_manage_power, + .rx_fixup = cdc_mbim_rx_fixup, + .tx_fixup = cdc_mbim_tx_fixup, +}; + +static const struct usb_device_id mbim_devs[] = { + /* This duplicate NCM entry is intentional. MBIM devices can + * be disguised as NCM by default, and this is necessary to + * allow us to bind the correct driver_info to such devices. + * + * bind() will sort out this for us, selecting the correct + * entry and reject the other + */ + { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE), + .driver_info = (unsigned long)&cdc_mbim_info, + }, + { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE), + .driver_info = (unsigned long)&cdc_mbim_info, + }, + { + }, +}; +MODULE_DEVICE_TABLE(usb, mbim_devs); + +static struct usb_driver cdc_mbim_driver = { + .name = "cdc_mbim", + .id_table = mbim_devs, + .probe = usbnet_probe, + .disconnect = usbnet_disconnect, + .suspend = cdc_mbim_suspend, + .resume = cdc_mbim_resume, + .reset_resume = cdc_mbim_resume, + .supports_autosuspend = 1, + .disable_hub_initiated_lpm = 1, +}; +module_usb_driver(cdc_mbim_driver); + +MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>"); +MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>"); +MODULE_DESCRIPTION("USB CDC MBIM host driver"); +MODULE_LICENSE("GPL"); |