Linux 3.11-rc3
[cris-mirror.git] / drivers / net / usb / cdc_mbim.c
blob872819851aef814f23d850a126e6ccd9ea1f5db4
1 /*
2 * Copyright (c) 2012 Smith Micro Software, Inc.
3 * Copyright (c) 2012 Bjørn Mork <bjorn@mork.no>
5 * This driver is based on and reuse most of cdc_ncm, which is
6 * Copyright (C) ST-Ericsson 2010-2012
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
13 #include <linux/module.h>
14 #include <linux/netdevice.h>
15 #include <linux/ethtool.h>
16 #include <linux/if_vlan.h>
17 #include <linux/ip.h>
18 #include <linux/mii.h>
19 #include <linux/usb.h>
20 #include <linux/usb/cdc.h>
21 #include <linux/usb/usbnet.h>
22 #include <linux/usb/cdc-wdm.h>
23 #include <linux/usb/cdc_ncm.h>
25 /* driver specific data - must match cdc_ncm usage */
26 struct cdc_mbim_state {
27 struct cdc_ncm_ctx *ctx;
28 atomic_t pmcount;
29 struct usb_driver *subdriver;
30 struct usb_interface *control;
31 struct usb_interface *data;
34 /* using a counter to merge subdriver requests with our own into a combined state */
35 static int cdc_mbim_manage_power(struct usbnet *dev, int on)
37 struct cdc_mbim_state *info = (void *)&dev->data;
38 int rv = 0;
40 dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
42 if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
43 /* need autopm_get/put here to ensure the usbcore sees the new value */
44 rv = usb_autopm_get_interface(dev->intf);
45 if (rv < 0)
46 goto err;
47 dev->intf->needs_remote_wakeup = on;
48 usb_autopm_put_interface(dev->intf);
50 err:
51 return rv;
54 static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
56 struct usbnet *dev = usb_get_intfdata(intf);
58 /* can be called while disconnecting */
59 if (!dev)
60 return 0;
62 return cdc_mbim_manage_power(dev, status);
66 static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
68 struct cdc_ncm_ctx *ctx;
69 struct usb_driver *subdriver = ERR_PTR(-ENODEV);
70 int ret = -ENODEV;
71 u8 data_altsetting = cdc_ncm_select_altsetting(dev, intf);
72 struct cdc_mbim_state *info = (void *)&dev->data;
74 /* Probably NCM, defer for cdc_ncm_bind */
75 if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
76 goto err;
78 ret = cdc_ncm_bind_common(dev, intf, data_altsetting);
79 if (ret)
80 goto err;
82 ctx = info->ctx;
84 /* The MBIM descriptor and the status endpoint are required */
85 if (ctx->mbim_desc && dev->status)
86 subdriver = usb_cdc_wdm_register(ctx->control,
87 &dev->status->desc,
88 le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
89 cdc_mbim_wdm_manage_power);
90 if (IS_ERR(subdriver)) {
91 ret = PTR_ERR(subdriver);
92 cdc_ncm_unbind(dev, intf);
93 goto err;
96 /* can't let usbnet use the interrupt endpoint */
97 dev->status = NULL;
98 info->subdriver = subdriver;
100 /* MBIM cannot do ARP */
101 dev->net->flags |= IFF_NOARP;
103 /* no need to put the VLAN tci in the packet headers */
104 dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX;
105 err:
106 return ret;
109 static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
111 struct cdc_mbim_state *info = (void *)&dev->data;
112 struct cdc_ncm_ctx *ctx = info->ctx;
114 /* disconnect subdriver from control interface */
115 if (info->subdriver && info->subdriver->disconnect)
116 info->subdriver->disconnect(ctx->control);
117 info->subdriver = NULL;
119 /* let NCM unbind clean up both control and data interface */
120 cdc_ncm_unbind(dev, intf);
124 static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
126 struct sk_buff *skb_out;
127 struct cdc_mbim_state *info = (void *)&dev->data;
128 struct cdc_ncm_ctx *ctx = info->ctx;
129 __le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
130 u16 tci = 0;
131 u8 *c;
133 if (!ctx)
134 goto error;
136 if (skb) {
137 if (skb->len <= ETH_HLEN)
138 goto error;
140 /* mapping VLANs to MBIM sessions:
141 * no tag => IPS session <0>
142 * 1 - 255 => IPS session <vlanid>
143 * 256 - 511 => DSS session <vlanid - 256>
144 * 512 - 4095 => unsupported, drop
146 vlan_get_tag(skb, &tci);
148 switch (tci & 0x0f00) {
149 case 0x0000: /* VLAN ID 0 - 255 */
150 /* verify that datagram is IPv4 or IPv6 */
151 skb_reset_mac_header(skb);
152 switch (eth_hdr(skb)->h_proto) {
153 case htons(ETH_P_IP):
154 case htons(ETH_P_IPV6):
155 break;
156 default:
157 goto error;
159 c = (u8 *)&sign;
160 c[3] = tci;
161 break;
162 case 0x0100: /* VLAN ID 256 - 511 */
163 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
164 c = (u8 *)&sign;
165 c[3] = tci;
166 break;
167 default:
168 netif_err(dev, tx_err, dev->net,
169 "unsupported tci=0x%04x\n", tci);
170 goto error;
172 skb_pull(skb, ETH_HLEN);
175 spin_lock_bh(&ctx->mtx);
176 skb_out = cdc_ncm_fill_tx_frame(ctx, skb, sign);
177 spin_unlock_bh(&ctx->mtx);
178 return skb_out;
180 error:
181 if (skb)
182 dev_kfree_skb_any(skb);
184 return NULL;
187 static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
189 __be16 proto = htons(ETH_P_802_3);
190 struct sk_buff *skb = NULL;
192 if (tci < 256) { /* IPS session? */
193 if (len < sizeof(struct iphdr))
194 goto err;
196 switch (*buf & 0xf0) {
197 case 0x40:
198 proto = htons(ETH_P_IP);
199 break;
200 case 0x60:
201 proto = htons(ETH_P_IPV6);
202 break;
203 default:
204 goto err;
208 skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN);
209 if (!skb)
210 goto err;
212 /* add an ethernet header */
213 skb_put(skb, ETH_HLEN);
214 skb_reset_mac_header(skb);
215 eth_hdr(skb)->h_proto = proto;
216 memset(eth_hdr(skb)->h_source, 0, ETH_ALEN);
217 memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
219 /* add datagram */
220 memcpy(skb_put(skb, len), buf, len);
222 /* map MBIM session to VLAN */
223 if (tci)
224 vlan_put_tag(skb, htons(ETH_P_8021Q), tci);
225 err:
226 return skb;
229 static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
231 struct sk_buff *skb;
232 struct cdc_mbim_state *info = (void *)&dev->data;
233 struct cdc_ncm_ctx *ctx = info->ctx;
234 int len;
235 int nframes;
236 int x;
237 int offset;
238 struct usb_cdc_ncm_ndp16 *ndp16;
239 struct usb_cdc_ncm_dpe16 *dpe16;
240 int ndpoffset;
241 int loopcount = 50; /* arbitrary max preventing infinite loop */
242 u8 *c;
243 u16 tci;
245 ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
246 if (ndpoffset < 0)
247 goto error;
249 next_ndp:
250 nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
251 if (nframes < 0)
252 goto error;
254 ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
256 switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
257 case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
258 c = (u8 *)&ndp16->dwSignature;
259 tci = c[3];
260 break;
261 case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
262 c = (u8 *)&ndp16->dwSignature;
263 tci = c[3] + 256;
264 break;
265 default:
266 netif_dbg(dev, rx_err, dev->net,
267 "unsupported NDP signature <0x%08x>\n",
268 le32_to_cpu(ndp16->dwSignature));
269 goto err_ndp;
273 dpe16 = ndp16->dpe16;
274 for (x = 0; x < nframes; x++, dpe16++) {
275 offset = le16_to_cpu(dpe16->wDatagramIndex);
276 len = le16_to_cpu(dpe16->wDatagramLength);
279 * CDC NCM ch. 3.7
280 * All entries after first NULL entry are to be ignored
282 if ((offset == 0) || (len == 0)) {
283 if (!x)
284 goto err_ndp; /* empty NTB */
285 break;
288 /* sanity checking */
289 if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
290 netif_dbg(dev, rx_err, dev->net,
291 "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
292 x, offset, len, skb_in);
293 if (!x)
294 goto err_ndp;
295 break;
296 } else {
297 skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
298 if (!skb)
299 goto error;
300 usbnet_skb_return(dev, skb);
303 err_ndp:
304 /* are there more NDPs to process? */
305 ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
306 if (ndpoffset && loopcount--)
307 goto next_ndp;
309 return 1;
310 error:
311 return 0;
314 static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
316 int ret = 0;
317 struct usbnet *dev = usb_get_intfdata(intf);
318 struct cdc_mbim_state *info = (void *)&dev->data;
319 struct cdc_ncm_ctx *ctx = info->ctx;
321 if (ctx == NULL) {
322 ret = -1;
323 goto error;
327 * Both usbnet_suspend() and subdriver->suspend() MUST return 0
328 * in system sleep context, otherwise, the resume callback has
329 * to recover device from previous suspend failure.
331 ret = usbnet_suspend(intf, message);
332 if (ret < 0)
333 goto error;
335 if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
336 ret = info->subdriver->suspend(intf, message);
337 if (ret < 0)
338 usbnet_resume(intf);
340 error:
341 return ret;
344 static int cdc_mbim_resume(struct usb_interface *intf)
346 int ret = 0;
347 struct usbnet *dev = usb_get_intfdata(intf);
348 struct cdc_mbim_state *info = (void *)&dev->data;
349 struct cdc_ncm_ctx *ctx = info->ctx;
350 bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
352 if (callsub)
353 ret = info->subdriver->resume(intf);
354 if (ret < 0)
355 goto err;
356 ret = usbnet_resume(intf);
357 if (ret < 0 && callsub && info->subdriver->suspend)
358 info->subdriver->suspend(intf, PMSG_SUSPEND);
359 err:
360 return ret;
363 static const struct driver_info cdc_mbim_info = {
364 .description = "CDC MBIM",
365 .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
366 .bind = cdc_mbim_bind,
367 .unbind = cdc_mbim_unbind,
368 .manage_power = cdc_mbim_manage_power,
369 .rx_fixup = cdc_mbim_rx_fixup,
370 .tx_fixup = cdc_mbim_tx_fixup,
373 /* MBIM and NCM devices should not need a ZLP after NTBs with
374 * dwNtbOutMaxSize length. This driver_info is for the exceptional
375 * devices requiring it anyway, allowing them to be supported without
376 * forcing the performance penalty on all the sane devices.
378 static const struct driver_info cdc_mbim_info_zlp = {
379 .description = "CDC MBIM",
380 .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
381 .bind = cdc_mbim_bind,
382 .unbind = cdc_mbim_unbind,
383 .manage_power = cdc_mbim_manage_power,
384 .rx_fixup = cdc_mbim_rx_fixup,
385 .tx_fixup = cdc_mbim_tx_fixup,
388 static const struct usb_device_id mbim_devs[] = {
389 /* This duplicate NCM entry is intentional. MBIM devices can
390 * be disguised as NCM by default, and this is necessary to
391 * allow us to bind the correct driver_info to such devices.
393 * bind() will sort out this for us, selecting the correct
394 * entry and reject the other
396 { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
397 .driver_info = (unsigned long)&cdc_mbim_info,
399 /* Sierra Wireless MC7710 need ZLPs */
400 { USB_DEVICE_AND_INTERFACE_INFO(0x1199, 0x68a2, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
401 .driver_info = (unsigned long)&cdc_mbim_info_zlp,
403 { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
404 .driver_info = (unsigned long)&cdc_mbim_info,
409 MODULE_DEVICE_TABLE(usb, mbim_devs);
411 static struct usb_driver cdc_mbim_driver = {
412 .name = "cdc_mbim",
413 .id_table = mbim_devs,
414 .probe = usbnet_probe,
415 .disconnect = usbnet_disconnect,
416 .suspend = cdc_mbim_suspend,
417 .resume = cdc_mbim_resume,
418 .reset_resume = cdc_mbim_resume,
419 .supports_autosuspend = 1,
420 .disable_hub_initiated_lpm = 1,
422 module_usb_driver(cdc_mbim_driver);
424 MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
425 MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
426 MODULE_DESCRIPTION("USB CDC MBIM host driver");
427 MODULE_LICENSE("GPL");