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1 /*
2  * cdc_ncm.c
3  *
4  * Copyright (C) ST-Ericsson 2010-2012
5  * Contact: Alexey Orishko <alexey.orishko@stericsson.com>
6  * Original author: Hans Petter Selasky <hans.petter.selasky@stericsson.com>
7  *
8  * USB Host Driver for Network Control Model (NCM)
9  * http://www.usb.org/developers/docs/devclass_docs/NCM10_012011.zip
10  *
11  * The NCM encoding, decoding and initialization logic
12  * derives from FreeBSD 8.x. if_cdce.c and if_cdcereg.h
13  *
14  * This software is available to you under a choice of one of two
15  * licenses. You may choose this file to be licensed under the terms
16  * of the GNU General Public License (GPL) Version 2 or the 2-clause
17  * BSD license listed below:
18  *
19  * Redistribution and use in source and binary forms, with or without
20  * modification, are permitted provided that the following conditions
21  * are met:
22  * 1. Redistributions of source code must retain the above copyright
23  *    notice, this list of conditions and the following disclaimer.
24  * 2. Redistributions in binary form must reproduce the above copyright
25  *    notice, this list of conditions and the following disclaimer in the
26  *    documentation and/or other materials provided with the distribution.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #include <linux/module.h>
42 #include <linux/netdevice.h>
43 #include <linux/ctype.h>
44 #include <linux/etherdevice.h>
45 #include <linux/ethtool.h>
46 #include <linux/workqueue.h>
47 #include <linux/mii.h>
48 #include <linux/crc32.h>
49 #include <linux/usb.h>
50 #include <linux/hrtimer.h>
51 #include <linux/atomic.h>
52 #include <linux/usb/usbnet.h>
53 #include <linux/usb/cdc.h>
54 #include <linux/usb/cdc_ncm.h>
55 
56 #if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM)
57 static bool prefer_mbim = true;
58 #else
59 static bool prefer_mbim;
60 #endif
61 module_param(prefer_mbim, bool, S_IRUGO | S_IWUSR);
62 MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
63 
64 static void cdc_ncm_txpath_bh(unsigned long param);
65 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
66 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
67 static struct usb_driver cdc_ncm_driver;
68 
69 struct cdc_ncm_stats {
70 	char stat_string[ETH_GSTRING_LEN];
71 	int sizeof_stat;
72 	int stat_offset;
73 };
74 
75 #define CDC_NCM_STAT(str, m) { \
76 		.stat_string = str, \
77 		.sizeof_stat = sizeof(((struct cdc_ncm_ctx *)0)->m), \
78 		.stat_offset = offsetof(struct cdc_ncm_ctx, m) }
79 #define CDC_NCM_SIMPLE_STAT(m)	CDC_NCM_STAT(__stringify(m), m)
80 
81 static const struct cdc_ncm_stats cdc_ncm_gstrings_stats[] = {
82 	CDC_NCM_SIMPLE_STAT(tx_reason_ntb_full),
83 	CDC_NCM_SIMPLE_STAT(tx_reason_ndp_full),
84 	CDC_NCM_SIMPLE_STAT(tx_reason_timeout),
85 	CDC_NCM_SIMPLE_STAT(tx_reason_max_datagram),
86 	CDC_NCM_SIMPLE_STAT(tx_overhead),
87 	CDC_NCM_SIMPLE_STAT(tx_ntbs),
88 	CDC_NCM_SIMPLE_STAT(rx_overhead),
89 	CDC_NCM_SIMPLE_STAT(rx_ntbs),
90 };
91 
cdc_ncm_get_sset_count(struct net_device __always_unused * netdev,int sset)92 static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset)
93 {
94 	switch (sset) {
95 	case ETH_SS_STATS:
96 		return ARRAY_SIZE(cdc_ncm_gstrings_stats);
97 	default:
98 		return -EOPNOTSUPP;
99 	}
100 }
101 
cdc_ncm_get_ethtool_stats(struct net_device * netdev,struct ethtool_stats __always_unused * stats,u64 * data)102 static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
103 				    struct ethtool_stats __always_unused *stats,
104 				    u64 *data)
105 {
106 	struct usbnet *dev = netdev_priv(netdev);
107 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
108 	int i;
109 	char *p = NULL;
110 
111 	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
112 		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
113 		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
114 	}
115 }
116 
cdc_ncm_get_strings(struct net_device __always_unused * netdev,u32 stringset,u8 * data)117 static void cdc_ncm_get_strings(struct net_device __always_unused *netdev, u32 stringset, u8 *data)
118 {
119 	u8 *p = data;
120 	int i;
121 
122 	switch (stringset) {
123 	case ETH_SS_STATS:
124 		for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
125 			memcpy(p, cdc_ncm_gstrings_stats[i].stat_string, ETH_GSTRING_LEN);
126 			p += ETH_GSTRING_LEN;
127 		}
128 	}
129 }
130 
131 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx);
132 
133 static const struct ethtool_ops cdc_ncm_ethtool_ops = {
134 	.get_settings      = usbnet_get_settings,
135 	.set_settings      = usbnet_set_settings,
136 	.get_link          = usbnet_get_link,
137 	.nway_reset        = usbnet_nway_reset,
138 	.get_drvinfo       = usbnet_get_drvinfo,
139 	.get_msglevel      = usbnet_get_msglevel,
140 	.set_msglevel      = usbnet_set_msglevel,
141 	.get_ts_info       = ethtool_op_get_ts_info,
142 	.get_sset_count    = cdc_ncm_get_sset_count,
143 	.get_strings       = cdc_ncm_get_strings,
144 	.get_ethtool_stats = cdc_ncm_get_ethtool_stats,
145 };
146 
cdc_ncm_check_rx_max(struct usbnet * dev,u32 new_rx)147 static u32 cdc_ncm_check_rx_max(struct usbnet *dev, u32 new_rx)
148 {
149 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
150 	u32 val, max, min;
151 
152 	/* clamp new_rx to sane values */
153 	min = USB_CDC_NCM_NTB_MIN_IN_SIZE;
154 	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_RX, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
155 
156 	/* dwNtbInMaxSize spec violation? Use MIN size for both limits */
157 	if (max < min) {
158 		dev_warn(&dev->intf->dev, "dwNtbInMaxSize=%u is too small. Using %u\n",
159 			 le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize), min);
160 		max = min;
161 	}
162 
163 	val = clamp_t(u32, new_rx, min, max);
164 	if (val != new_rx)
165 		dev_dbg(&dev->intf->dev, "rx_max must be in the [%u, %u] range\n", min, max);
166 
167 	return val;
168 }
169 
cdc_ncm_check_tx_max(struct usbnet * dev,u32 new_tx)170 static u32 cdc_ncm_check_tx_max(struct usbnet *dev, u32 new_tx)
171 {
172 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
173 	u32 val, max, min;
174 
175 	/* clamp new_tx to sane values */
176 	min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth16);
177 	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_TX, le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
178 	if (max == 0)
179 		max = CDC_NCM_NTB_MAX_SIZE_TX; /* dwNtbOutMaxSize not set */
180 
181 	/* some devices set dwNtbOutMaxSize too low for the above default */
182 	min = min(min, max);
183 
184 	val = clamp_t(u32, new_tx, min, max);
185 	if (val != new_tx)
186 		dev_dbg(&dev->intf->dev, "tx_max must be in the [%u, %u] range\n", min, max);
187 
188 	return val;
189 }
190 
cdc_ncm_show_min_tx_pkt(struct device * d,struct device_attribute * attr,char * buf)191 static ssize_t cdc_ncm_show_min_tx_pkt(struct device *d, struct device_attribute *attr, char *buf)
192 {
193 	struct usbnet *dev = netdev_priv(to_net_dev(d));
194 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
195 
196 	return sprintf(buf, "%u\n", ctx->min_tx_pkt);
197 }
198 
cdc_ncm_show_rx_max(struct device * d,struct device_attribute * attr,char * buf)199 static ssize_t cdc_ncm_show_rx_max(struct device *d, struct device_attribute *attr, char *buf)
200 {
201 	struct usbnet *dev = netdev_priv(to_net_dev(d));
202 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
203 
204 	return sprintf(buf, "%u\n", ctx->rx_max);
205 }
206 
cdc_ncm_show_tx_max(struct device * d,struct device_attribute * attr,char * buf)207 static ssize_t cdc_ncm_show_tx_max(struct device *d, struct device_attribute *attr, char *buf)
208 {
209 	struct usbnet *dev = netdev_priv(to_net_dev(d));
210 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
211 
212 	return sprintf(buf, "%u\n", ctx->tx_max);
213 }
214 
cdc_ncm_show_tx_timer_usecs(struct device * d,struct device_attribute * attr,char * buf)215 static ssize_t cdc_ncm_show_tx_timer_usecs(struct device *d, struct device_attribute *attr, char *buf)
216 {
217 	struct usbnet *dev = netdev_priv(to_net_dev(d));
218 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
219 
220 	return sprintf(buf, "%u\n", ctx->timer_interval / (u32)NSEC_PER_USEC);
221 }
222 
cdc_ncm_store_min_tx_pkt(struct device * d,struct device_attribute * attr,const char * buf,size_t len)223 static ssize_t cdc_ncm_store_min_tx_pkt(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
224 {
225 	struct usbnet *dev = netdev_priv(to_net_dev(d));
226 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
227 	unsigned long val;
228 
229 	/* no need to restrict values - anything from 0 to infinity is OK */
230 	if (kstrtoul(buf, 0, &val))
231 		return -EINVAL;
232 
233 	ctx->min_tx_pkt = val;
234 	return len;
235 }
236 
cdc_ncm_store_rx_max(struct device * d,struct device_attribute * attr,const char * buf,size_t len)237 static ssize_t cdc_ncm_store_rx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
238 {
239 	struct usbnet *dev = netdev_priv(to_net_dev(d));
240 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
241 	unsigned long val;
242 
243 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_rx_max(dev, val) != val)
244 		return -EINVAL;
245 
246 	cdc_ncm_update_rxtx_max(dev, val, ctx->tx_max);
247 	return len;
248 }
249 
cdc_ncm_store_tx_max(struct device * d,struct device_attribute * attr,const char * buf,size_t len)250 static ssize_t cdc_ncm_store_tx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
251 {
252 	struct usbnet *dev = netdev_priv(to_net_dev(d));
253 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
254 	unsigned long val;
255 
256 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_tx_max(dev, val) != val)
257 		return -EINVAL;
258 
259 	cdc_ncm_update_rxtx_max(dev, ctx->rx_max, val);
260 	return len;
261 }
262 
cdc_ncm_store_tx_timer_usecs(struct device * d,struct device_attribute * attr,const char * buf,size_t len)263 static ssize_t cdc_ncm_store_tx_timer_usecs(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
264 {
265 	struct usbnet *dev = netdev_priv(to_net_dev(d));
266 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
267 	ssize_t ret;
268 	unsigned long val;
269 
270 	ret = kstrtoul(buf, 0, &val);
271 	if (ret)
272 		return ret;
273 	if (val && (val < CDC_NCM_TIMER_INTERVAL_MIN || val > CDC_NCM_TIMER_INTERVAL_MAX))
274 		return -EINVAL;
275 
276 	spin_lock_bh(&ctx->mtx);
277 	ctx->timer_interval = val * NSEC_PER_USEC;
278 	if (!ctx->timer_interval)
279 		ctx->tx_timer_pending = 0;
280 	spin_unlock_bh(&ctx->mtx);
281 	return len;
282 }
283 
284 static DEVICE_ATTR(min_tx_pkt, S_IRUGO | S_IWUSR, cdc_ncm_show_min_tx_pkt, cdc_ncm_store_min_tx_pkt);
285 static DEVICE_ATTR(rx_max, S_IRUGO | S_IWUSR, cdc_ncm_show_rx_max, cdc_ncm_store_rx_max);
286 static DEVICE_ATTR(tx_max, S_IRUGO | S_IWUSR, cdc_ncm_show_tx_max, cdc_ncm_store_tx_max);
287 static DEVICE_ATTR(tx_timer_usecs, S_IRUGO | S_IWUSR, cdc_ncm_show_tx_timer_usecs, cdc_ncm_store_tx_timer_usecs);
288 
289 #define NCM_PARM_ATTR(name, format, tocpu)				\
290 static ssize_t cdc_ncm_show_##name(struct device *d, struct device_attribute *attr, char *buf) \
291 { \
292 	struct usbnet *dev = netdev_priv(to_net_dev(d)); \
293 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; \
294 	return sprintf(buf, format "\n", tocpu(ctx->ncm_parm.name));	\
295 } \
296 static DEVICE_ATTR(name, S_IRUGO, cdc_ncm_show_##name, NULL)
297 
298 NCM_PARM_ATTR(bmNtbFormatsSupported, "0x%04x", le16_to_cpu);
299 NCM_PARM_ATTR(dwNtbInMaxSize, "%u", le32_to_cpu);
300 NCM_PARM_ATTR(wNdpInDivisor, "%u", le16_to_cpu);
301 NCM_PARM_ATTR(wNdpInPayloadRemainder, "%u", le16_to_cpu);
302 NCM_PARM_ATTR(wNdpInAlignment, "%u", le16_to_cpu);
303 NCM_PARM_ATTR(dwNtbOutMaxSize, "%u", le32_to_cpu);
304 NCM_PARM_ATTR(wNdpOutDivisor, "%u", le16_to_cpu);
305 NCM_PARM_ATTR(wNdpOutPayloadRemainder, "%u", le16_to_cpu);
306 NCM_PARM_ATTR(wNdpOutAlignment, "%u", le16_to_cpu);
307 NCM_PARM_ATTR(wNtbOutMaxDatagrams, "%u", le16_to_cpu);
308 
309 static struct attribute *cdc_ncm_sysfs_attrs[] = {
310 	&dev_attr_min_tx_pkt.attr,
311 	&dev_attr_rx_max.attr,
312 	&dev_attr_tx_max.attr,
313 	&dev_attr_tx_timer_usecs.attr,
314 	&dev_attr_bmNtbFormatsSupported.attr,
315 	&dev_attr_dwNtbInMaxSize.attr,
316 	&dev_attr_wNdpInDivisor.attr,
317 	&dev_attr_wNdpInPayloadRemainder.attr,
318 	&dev_attr_wNdpInAlignment.attr,
319 	&dev_attr_dwNtbOutMaxSize.attr,
320 	&dev_attr_wNdpOutDivisor.attr,
321 	&dev_attr_wNdpOutPayloadRemainder.attr,
322 	&dev_attr_wNdpOutAlignment.attr,
323 	&dev_attr_wNtbOutMaxDatagrams.attr,
324 	NULL,
325 };
326 
327 static struct attribute_group cdc_ncm_sysfs_attr_group = {
328 	.name = "cdc_ncm",
329 	.attrs = cdc_ncm_sysfs_attrs,
330 };
331 
332 /* handle rx_max and tx_max changes */
cdc_ncm_update_rxtx_max(struct usbnet * dev,u32 new_rx,u32 new_tx)333 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx)
334 {
335 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
336 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
337 	u32 val;
338 
339 	val = cdc_ncm_check_rx_max(dev, new_rx);
340 
341 	/* inform device about NTB input size changes */
342 	if (val != ctx->rx_max) {
343 		__le32 dwNtbInMaxSize = cpu_to_le32(val);
344 
345 		dev_info(&dev->intf->dev, "setting rx_max = %u\n", val);
346 
347 		/* tell device to use new size */
348 		if (usbnet_write_cmd(dev, USB_CDC_SET_NTB_INPUT_SIZE,
349 				     USB_TYPE_CLASS | USB_DIR_OUT
350 				     | USB_RECIP_INTERFACE,
351 				     0, iface_no, &dwNtbInMaxSize, 4) < 0)
352 			dev_dbg(&dev->intf->dev, "Setting NTB Input Size failed\n");
353 		else
354 			ctx->rx_max = val;
355 	}
356 
357 	/* usbnet use these values for sizing rx queues */
358 	if (dev->rx_urb_size != ctx->rx_max) {
359 		dev->rx_urb_size = ctx->rx_max;
360 		if (netif_running(dev->net))
361 			usbnet_unlink_rx_urbs(dev);
362 	}
363 
364 	val = cdc_ncm_check_tx_max(dev, new_tx);
365 	if (val != ctx->tx_max)
366 		dev_info(&dev->intf->dev, "setting tx_max = %u\n", val);
367 
368 	/* Adding a pad byte here if necessary simplifies the handling
369 	 * in cdc_ncm_fill_tx_frame, making tx_max always represent
370 	 * the real skb max size.
371 	 *
372 	 * We cannot use dev->maxpacket here because this is called from
373 	 * .bind which is called before usbnet sets up dev->maxpacket
374 	 */
375 	if (val != le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) &&
376 	    val % usb_maxpacket(dev->udev, dev->out, 1) == 0)
377 		val++;
378 
379 	/* we might need to flush any pending tx buffers if running */
380 	if (netif_running(dev->net) && val > ctx->tx_max) {
381 		netif_tx_lock_bh(dev->net);
382 		usbnet_start_xmit(NULL, dev->net);
383 		/* make sure tx_curr_skb is reallocated if it was empty */
384 		if (ctx->tx_curr_skb) {
385 			dev_kfree_skb_any(ctx->tx_curr_skb);
386 			ctx->tx_curr_skb = NULL;
387 		}
388 		ctx->tx_max = val;
389 		netif_tx_unlock_bh(dev->net);
390 	} else {
391 		ctx->tx_max = val;
392 	}
393 
394 	dev->hard_mtu = ctx->tx_max;
395 
396 	/* max qlen depend on hard_mtu and rx_urb_size */
397 	usbnet_update_max_qlen(dev);
398 
399 	/* never pad more than 3 full USB packets per transfer */
400 	ctx->min_tx_pkt = clamp_t(u16, ctx->tx_max - 3 * usb_maxpacket(dev->udev, dev->out, 1),
401 				  CDC_NCM_MIN_TX_PKT, ctx->tx_max);
402 }
403 
404 /* helpers for NCM and MBIM differences */
cdc_ncm_flags(struct usbnet * dev)405 static u8 cdc_ncm_flags(struct usbnet *dev)
406 {
407 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
408 
409 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
410 		return ctx->mbim_desc->bmNetworkCapabilities;
411 	if (ctx->func_desc)
412 		return ctx->func_desc->bmNetworkCapabilities;
413 	return 0;
414 }
415 
cdc_ncm_eth_hlen(struct usbnet * dev)416 static int cdc_ncm_eth_hlen(struct usbnet *dev)
417 {
418 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
419 		return 0;
420 	return ETH_HLEN;
421 }
422 
cdc_ncm_min_dgram_size(struct usbnet * dev)423 static u32 cdc_ncm_min_dgram_size(struct usbnet *dev)
424 {
425 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
426 		return CDC_MBIM_MIN_DATAGRAM_SIZE;
427 	return CDC_NCM_MIN_DATAGRAM_SIZE;
428 }
429 
cdc_ncm_max_dgram_size(struct usbnet * dev)430 static u32 cdc_ncm_max_dgram_size(struct usbnet *dev)
431 {
432 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
433 
434 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
435 		return le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
436 	if (ctx->ether_desc)
437 		return le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
438 	return CDC_NCM_MAX_DATAGRAM_SIZE;
439 }
440 
441 /* initial one-time device setup.  MUST be called with the data interface
442  * in altsetting 0
443  */
cdc_ncm_init(struct usbnet * dev)444 static int cdc_ncm_init(struct usbnet *dev)
445 {
446 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
447 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
448 	int err;
449 
450 	err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
451 			      USB_TYPE_CLASS | USB_DIR_IN
452 			      |USB_RECIP_INTERFACE,
453 			      0, iface_no, &ctx->ncm_parm,
454 			      sizeof(ctx->ncm_parm));
455 	if (err < 0) {
456 		dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
457 		return err; /* GET_NTB_PARAMETERS is required */
458 	}
459 
460 	/* set CRC Mode */
461 	if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
462 		dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
463 		err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
464 				       USB_TYPE_CLASS | USB_DIR_OUT
465 				       | USB_RECIP_INTERFACE,
466 				       USB_CDC_NCM_CRC_NOT_APPENDED,
467 				       iface_no, NULL, 0);
468 		if (err < 0)
469 			dev_err(&dev->intf->dev, "SET_CRC_MODE failed\n");
470 	}
471 
472 	/* set NTB format, if both formats are supported.
473 	 *
474 	 * "The host shall only send this command while the NCM Data
475 	 *  Interface is in alternate setting 0."
476 	 */
477 	if (le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported) &
478 						USB_CDC_NCM_NTB32_SUPPORTED) {
479 		dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit\n");
480 		err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
481 				       USB_TYPE_CLASS | USB_DIR_OUT
482 				       | USB_RECIP_INTERFACE,
483 				       USB_CDC_NCM_NTB16_FORMAT,
484 				       iface_no, NULL, 0);
485 		if (err < 0)
486 			dev_err(&dev->intf->dev, "SET_NTB_FORMAT failed\n");
487 	}
488 
489 	/* set initial device values */
490 	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
491 	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
492 	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
493 	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
494 	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
495 	/* devices prior to NCM Errata shall set this field to zero */
496 	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
497 
498 	dev_dbg(&dev->intf->dev,
499 		"dwNtbInMaxSize=%u dwNtbOutMaxSize=%u wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
500 		ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
501 		ctx->tx_ndp_modulus, ctx->tx_max_datagrams, cdc_ncm_flags(dev));
502 
503 	/* max count of tx datagrams */
504 	if ((ctx->tx_max_datagrams == 0) ||
505 			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
506 		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
507 
508 	/* set up maximum NDP size */
509 	ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp16) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe16);
510 
511 	/* initial coalescing timer interval */
512 	ctx->timer_interval = CDC_NCM_TIMER_INTERVAL_USEC * NSEC_PER_USEC;
513 
514 	return 0;
515 }
516 
517 /* set a new max datagram size */
cdc_ncm_set_dgram_size(struct usbnet * dev,int new_size)518 static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
519 {
520 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
521 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
522 	__le16 max_datagram_size;
523 	u16 mbim_mtu;
524 	int err;
525 
526 	/* set default based on descriptors */
527 	ctx->max_datagram_size = clamp_t(u32, new_size,
528 					 cdc_ncm_min_dgram_size(dev),
529 					 CDC_NCM_MAX_DATAGRAM_SIZE);
530 
531 	/* inform the device about the selected Max Datagram Size? */
532 	if (!(cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
533 		goto out;
534 
535 	/* read current mtu value from device */
536 	err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
537 			      USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
538 			      0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
539 	if (err != sizeof(max_datagram_size)) {
540 		dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
541 		goto out;
542 	}
543 
544 	if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
545 		goto out;
546 
547 	max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
548 	err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
549 			       USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
550 			       0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
551 	if (err < 0)
552 		dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
553 
554 out:
555 	/* set MTU to max supported by the device if necessary */
556 	dev->net->mtu = min_t(int, dev->net->mtu, ctx->max_datagram_size - cdc_ncm_eth_hlen(dev));
557 
558 	/* do not exceed operater preferred MTU */
559 	if (ctx->mbim_extended_desc) {
560 		mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
561 		if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
562 			dev->net->mtu = mbim_mtu;
563 	}
564 }
565 
cdc_ncm_fix_modulus(struct usbnet * dev)566 static void cdc_ncm_fix_modulus(struct usbnet *dev)
567 {
568 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
569 	u32 val;
570 
571 	/*
572 	 * verify that the structure alignment is:
573 	 * - power of two
574 	 * - not greater than the maximum transmit length
575 	 * - not less than four bytes
576 	 */
577 	val = ctx->tx_ndp_modulus;
578 
579 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
580 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
581 		dev_dbg(&dev->intf->dev, "Using default alignment: 4 bytes\n");
582 		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
583 	}
584 
585 	/*
586 	 * verify that the payload alignment is:
587 	 * - power of two
588 	 * - not greater than the maximum transmit length
589 	 * - not less than four bytes
590 	 */
591 	val = ctx->tx_modulus;
592 
593 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
594 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
595 		dev_dbg(&dev->intf->dev, "Using default transmit modulus: 4 bytes\n");
596 		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
597 	}
598 
599 	/* verify the payload remainder */
600 	if (ctx->tx_remainder >= ctx->tx_modulus) {
601 		dev_dbg(&dev->intf->dev, "Using default transmit remainder: 0 bytes\n");
602 		ctx->tx_remainder = 0;
603 	}
604 
605 	/* adjust TX-remainder according to NCM specification. */
606 	ctx->tx_remainder = ((ctx->tx_remainder - cdc_ncm_eth_hlen(dev)) &
607 			     (ctx->tx_modulus - 1));
608 }
609 
cdc_ncm_setup(struct usbnet * dev)610 static int cdc_ncm_setup(struct usbnet *dev)
611 {
612 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
613 	u32 def_rx, def_tx;
614 
615 	/* be conservative when selecting intial buffer size to
616 	 * increase the number of hosts this will work for
617 	 */
618 	def_rx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_RX,
619 		       le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
620 	def_tx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_TX,
621 		       le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
622 
623 	/* clamp rx_max and tx_max and inform device */
624 	cdc_ncm_update_rxtx_max(dev, def_rx, def_tx);
625 
626 	/* sanitize the modulus and remainder values */
627 	cdc_ncm_fix_modulus(dev);
628 
629 	/* set max datagram size */
630 	cdc_ncm_set_dgram_size(dev, cdc_ncm_max_dgram_size(dev));
631 	return 0;
632 }
633 
634 static void
cdc_ncm_find_endpoints(struct usbnet * dev,struct usb_interface * intf)635 cdc_ncm_find_endpoints(struct usbnet *dev, struct usb_interface *intf)
636 {
637 	struct usb_host_endpoint *e, *in = NULL, *out = NULL;
638 	u8 ep;
639 
640 	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
641 		e = intf->cur_altsetting->endpoint + ep;
642 
643 		/* ignore endpoints which cannot transfer data */
644 		if (!usb_endpoint_maxp(&e->desc))
645 			continue;
646 
647 		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
648 		case USB_ENDPOINT_XFER_INT:
649 			if (usb_endpoint_dir_in(&e->desc)) {
650 				if (!dev->status)
651 					dev->status = e;
652 			}
653 			break;
654 
655 		case USB_ENDPOINT_XFER_BULK:
656 			if (usb_endpoint_dir_in(&e->desc)) {
657 				if (!in)
658 					in = e;
659 			} else {
660 				if (!out)
661 					out = e;
662 			}
663 			break;
664 
665 		default:
666 			break;
667 		}
668 	}
669 	if (in && !dev->in)
670 		dev->in = usb_rcvbulkpipe(dev->udev,
671 					  in->desc.bEndpointAddress &
672 					  USB_ENDPOINT_NUMBER_MASK);
673 	if (out && !dev->out)
674 		dev->out = usb_sndbulkpipe(dev->udev,
675 					   out->desc.bEndpointAddress &
676 					   USB_ENDPOINT_NUMBER_MASK);
677 }
678 
cdc_ncm_free(struct cdc_ncm_ctx * ctx)679 static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
680 {
681 	if (ctx == NULL)
682 		return;
683 
684 	if (ctx->tx_rem_skb != NULL) {
685 		dev_kfree_skb_any(ctx->tx_rem_skb);
686 		ctx->tx_rem_skb = NULL;
687 	}
688 
689 	if (ctx->tx_curr_skb != NULL) {
690 		dev_kfree_skb_any(ctx->tx_curr_skb);
691 		ctx->tx_curr_skb = NULL;
692 	}
693 
694 	kfree(ctx->delayed_ndp16);
695 
696 	kfree(ctx);
697 }
698 
699 /* we need to override the usbnet change_mtu ndo for two reasons:
700  *  - respect the negotiated maximum datagram size
701  *  - avoid unwanted changes to rx and tx buffers
702  */
cdc_ncm_change_mtu(struct net_device * net,int new_mtu)703 int cdc_ncm_change_mtu(struct net_device *net, int new_mtu)
704 {
705 	struct usbnet *dev = netdev_priv(net);
706 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
707 	int maxmtu = ctx->max_datagram_size - cdc_ncm_eth_hlen(dev);
708 
709 	if (new_mtu <= 0 || new_mtu > maxmtu)
710 		return -EINVAL;
711 	net->mtu = new_mtu;
712 	return 0;
713 }
714 EXPORT_SYMBOL_GPL(cdc_ncm_change_mtu);
715 
716 static const struct net_device_ops cdc_ncm_netdev_ops = {
717 	.ndo_open	     = usbnet_open,
718 	.ndo_stop	     = usbnet_stop,
719 	.ndo_start_xmit	     = usbnet_start_xmit,
720 	.ndo_tx_timeout	     = usbnet_tx_timeout,
721 	.ndo_change_mtu	     = cdc_ncm_change_mtu,
722 	.ndo_set_mac_address = eth_mac_addr,
723 	.ndo_validate_addr   = eth_validate_addr,
724 };
725 
cdc_ncm_bind_common(struct usbnet * dev,struct usb_interface * intf,u8 data_altsetting,int drvflags)726 int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting, int drvflags)
727 {
728 	struct cdc_ncm_ctx *ctx;
729 	struct usb_driver *driver;
730 	u8 *buf;
731 	int len;
732 	int temp;
733 	int err;
734 	u8 iface_no;
735 	struct usb_cdc_parsed_header hdr;
736 	__le16 curr_ntb_format;
737 
738 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
739 	if (!ctx)
740 		return -ENOMEM;
741 
742 	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
743 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
744 	ctx->bh.data = (unsigned long)dev;
745 	ctx->bh.func = cdc_ncm_txpath_bh;
746 	atomic_set(&ctx->stop, 0);
747 	spin_lock_init(&ctx->mtx);
748 
749 	/* store ctx pointer in device data field */
750 	dev->data[0] = (unsigned long)ctx;
751 
752 	/* only the control interface can be successfully probed */
753 	ctx->control = intf;
754 
755 	/* get some pointers */
756 	driver = driver_of(intf);
757 	buf = intf->cur_altsetting->extra;
758 	len = intf->cur_altsetting->extralen;
759 
760 	/* parse through descriptors associated with control interface */
761 	cdc_parse_cdc_header(&hdr, intf, buf, len);
762 
763 	if (hdr.usb_cdc_union_desc)
764 		ctx->data = usb_ifnum_to_if(dev->udev,
765 					    hdr.usb_cdc_union_desc->bSlaveInterface0);
766 	ctx->ether_desc = hdr.usb_cdc_ether_desc;
767 	ctx->func_desc = hdr.usb_cdc_ncm_desc;
768 	ctx->mbim_desc = hdr.usb_cdc_mbim_desc;
769 	ctx->mbim_extended_desc = hdr.usb_cdc_mbim_extended_desc;
770 
771 	/* some buggy devices have an IAD but no CDC Union */
772 	if (!hdr.usb_cdc_union_desc && intf->intf_assoc && intf->intf_assoc->bInterfaceCount == 2) {
773 		ctx->data = usb_ifnum_to_if(dev->udev, intf->cur_altsetting->desc.bInterfaceNumber + 1);
774 		dev_dbg(&intf->dev, "CDC Union missing - got slave from IAD\n");
775 	}
776 
777 	/* check if we got everything */
778 	if (!ctx->data) {
779 		dev_dbg(&intf->dev, "CDC Union missing and no IAD found\n");
780 		goto error;
781 	}
782 	if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) {
783 		if (!ctx->mbim_desc) {
784 			dev_dbg(&intf->dev, "MBIM functional descriptor missing\n");
785 			goto error;
786 		}
787 	} else {
788 		if (!ctx->ether_desc || !ctx->func_desc) {
789 			dev_dbg(&intf->dev, "NCM or ECM functional descriptors missing\n");
790 			goto error;
791 		}
792 	}
793 
794 	/* claim data interface, if different from control */
795 	if (ctx->data != ctx->control) {
796 		temp = usb_driver_claim_interface(driver, ctx->data, dev);
797 		if (temp) {
798 			dev_dbg(&intf->dev, "failed to claim data intf\n");
799 			goto error;
800 		}
801 	}
802 
803 	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
804 
805 	/* Reset data interface. Some devices will not reset properly
806 	 * unless they are configured first.  Toggle the altsetting to
807 	 * force a reset
808 	 */
809 	usb_set_interface(dev->udev, iface_no, data_altsetting);
810 	temp = usb_set_interface(dev->udev, iface_no, 0);
811 	if (temp) {
812 		dev_dbg(&intf->dev, "set interface failed\n");
813 		goto error2;
814 	}
815 
816 	/* initialize basic device settings */
817 	if (cdc_ncm_init(dev))
818 		goto error2;
819 
820 	/* Some firmwares need a pause here or they will silently fail
821 	 * to set up the interface properly.  This value was decided
822 	 * empirically on a Sierra Wireless MC7455 running 02.08.02.00
823 	 * firmware.
824 	 */
825 	usleep_range(10000, 20000);
826 
827 	/* configure data interface */
828 	temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
829 	if (temp) {
830 		dev_dbg(&intf->dev, "set interface failed\n");
831 		goto error2;
832 	}
833 
834 	/* Device-specific flags */
835 	ctx->drvflags = drvflags;
836 
837 	/*
838 	 * Some Huawei devices have been observed to come out of reset in NDP32 mode.
839 	 * Let's check if this is the case, and set the device to NDP16 mode again if
840 	 * needed.
841 	*/
842 	if (ctx->drvflags & CDC_NCM_FLAG_RESET_NTB16) {
843 		err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_FORMAT,
844 				      USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
845 				      0, iface_no, &curr_ntb_format, 2);
846 		if (err < 0) {
847 			goto error2;
848 		}
849 
850 		if (curr_ntb_format == cpu_to_le16(USB_CDC_NCM_NTB32_FORMAT)) {
851 			dev_info(&intf->dev, "resetting NTB format to 16-bit");
852 			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
853 					       USB_TYPE_CLASS | USB_DIR_OUT
854 					       | USB_RECIP_INTERFACE,
855 					       USB_CDC_NCM_NTB16_FORMAT,
856 					       iface_no, NULL, 0);
857 
858 			if (err < 0)
859 				goto error2;
860 		}
861 	}
862 
863 	cdc_ncm_find_endpoints(dev, ctx->data);
864 	cdc_ncm_find_endpoints(dev, ctx->control);
865 	if (!dev->in || !dev->out || !dev->status) {
866 		dev_dbg(&intf->dev, "failed to collect endpoints\n");
867 		goto error2;
868 	}
869 
870 	usb_set_intfdata(ctx->data, dev);
871 	usb_set_intfdata(ctx->control, dev);
872 
873 	if (ctx->ether_desc) {
874 		temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
875 		if (temp) {
876 			dev_dbg(&intf->dev, "failed to get mac address\n");
877 			goto error2;
878 		}
879 		dev_info(&intf->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
880 	}
881 
882 	/* finish setting up the device specific data */
883 	cdc_ncm_setup(dev);
884 
885 	/* Allocate the delayed NDP if needed. */
886 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
887 		ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
888 		if (!ctx->delayed_ndp16)
889 			goto error2;
890 		dev_info(&intf->dev, "NDP will be placed at end of frame for this device.");
891 	}
892 
893 	/* override ethtool_ops */
894 	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
895 
896 	/* add our sysfs attrs */
897 	dev->net->sysfs_groups[0] = &cdc_ncm_sysfs_attr_group;
898 
899 	/* must handle MTU changes */
900 	dev->net->netdev_ops = &cdc_ncm_netdev_ops;
901 
902 	return 0;
903 
904 error2:
905 	usb_set_intfdata(ctx->control, NULL);
906 	usb_set_intfdata(ctx->data, NULL);
907 	if (ctx->data != ctx->control)
908 		usb_driver_release_interface(driver, ctx->data);
909 error:
910 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
911 	dev->data[0] = 0;
912 	dev_info(&intf->dev, "bind() failure\n");
913 	return -ENODEV;
914 }
915 EXPORT_SYMBOL_GPL(cdc_ncm_bind_common);
916 
cdc_ncm_unbind(struct usbnet * dev,struct usb_interface * intf)917 void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
918 {
919 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
920 	struct usb_driver *driver = driver_of(intf);
921 
922 	if (ctx == NULL)
923 		return;		/* no setup */
924 
925 	atomic_set(&ctx->stop, 1);
926 
927 	if (hrtimer_active(&ctx->tx_timer))
928 		hrtimer_cancel(&ctx->tx_timer);
929 
930 	tasklet_kill(&ctx->bh);
931 
932 	/* handle devices with combined control and data interface */
933 	if (ctx->control == ctx->data)
934 		ctx->data = NULL;
935 
936 	/* disconnect master --> disconnect slave */
937 	if (intf == ctx->control && ctx->data) {
938 		usb_set_intfdata(ctx->data, NULL);
939 		usb_driver_release_interface(driver, ctx->data);
940 		ctx->data = NULL;
941 
942 	} else if (intf == ctx->data && ctx->control) {
943 		usb_set_intfdata(ctx->control, NULL);
944 		usb_driver_release_interface(driver, ctx->control);
945 		ctx->control = NULL;
946 	}
947 
948 	usb_set_intfdata(intf, NULL);
949 	cdc_ncm_free(ctx);
950 }
951 EXPORT_SYMBOL_GPL(cdc_ncm_unbind);
952 
953 /* Return the number of the MBIM control interface altsetting iff it
954  * is preferred and available,
955  */
cdc_ncm_select_altsetting(struct usb_interface * intf)956 u8 cdc_ncm_select_altsetting(struct usb_interface *intf)
957 {
958 	struct usb_host_interface *alt;
959 
960 	/* The MBIM spec defines a NCM compatible default altsetting,
961 	 * which we may have matched:
962 	 *
963 	 *  "Functions that implement both NCM 1.0 and MBIM (an
964 	 *   “NCM/MBIM function”) according to this recommendation
965 	 *   shall provide two alternate settings for the
966 	 *   Communication Interface.  Alternate setting 0, and the
967 	 *   associated class and endpoint descriptors, shall be
968 	 *   constructed according to the rules given for the
969 	 *   Communication Interface in section 5 of [USBNCM10].
970 	 *   Alternate setting 1, and the associated class and
971 	 *   endpoint descriptors, shall be constructed according to
972 	 *   the rules given in section 6 (USB Device Model) of this
973 	 *   specification."
974 	 */
975 	if (intf->num_altsetting < 2)
976 		return intf->cur_altsetting->desc.bAlternateSetting;
977 
978 	if (prefer_mbim) {
979 		alt = usb_altnum_to_altsetting(intf, CDC_NCM_COMM_ALTSETTING_MBIM);
980 		if (alt && cdc_ncm_comm_intf_is_mbim(alt))
981 			return CDC_NCM_COMM_ALTSETTING_MBIM;
982 	}
983 	return CDC_NCM_COMM_ALTSETTING_NCM;
984 }
985 EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting);
986 
cdc_ncm_bind(struct usbnet * dev,struct usb_interface * intf)987 static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
988 {
989 	/* MBIM backwards compatible function? */
990 	if (cdc_ncm_select_altsetting(intf) != CDC_NCM_COMM_ALTSETTING_NCM)
991 		return -ENODEV;
992 
993 	/* The NCM data altsetting is fixed, so we hard-coded it.
994 	 * Additionally, generic NCM devices are assumed to accept arbitrarily
995 	 * placed NDP.
996 	 */
997 	return cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM, 0);
998 }
999 
cdc_ncm_align_tail(struct sk_buff * skb,size_t modulus,size_t remainder,size_t max)1000 static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max)
1001 {
1002 	size_t align = ALIGN(skb->len, modulus) - skb->len + remainder;
1003 
1004 	if (skb->len + align > max)
1005 		align = max - skb->len;
1006 	if (align && skb_tailroom(skb) >= align)
1007 		memset(skb_put(skb, align), 0, align);
1008 }
1009 
1010 /* return a pointer to a valid struct usb_cdc_ncm_ndp16 of type sign, possibly
1011  * allocating a new one within skb
1012  */
cdc_ncm_ndp(struct cdc_ncm_ctx * ctx,struct sk_buff * skb,__le32 sign,size_t reserve)1013 static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1014 {
1015 	struct usb_cdc_ncm_ndp16 *ndp16 = NULL;
1016 	struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
1017 	size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
1018 
1019 	/* If NDP should be moved to the end of the NCM package, we can't follow the
1020 	* NTH16 header as we would normally do. NDP isn't written to the SKB yet, and
1021 	* the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1022 	*/
1023 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1024 		if (ctx->delayed_ndp16->dwSignature == sign)
1025 			return ctx->delayed_ndp16;
1026 
1027 		/* We can only push a single NDP to the end. Return
1028 		 * NULL to send what we've already got and queue this
1029 		 * skb for later.
1030 		 */
1031 		else if (ctx->delayed_ndp16->dwSignature)
1032 			return NULL;
1033 	}
1034 
1035 	/* follow the chain of NDPs, looking for a match */
1036 	while (ndpoffset) {
1037 		ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
1038 		if  (ndp16->dwSignature == sign)
1039 			return ndp16;
1040 		ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1041 	}
1042 
1043 	/* align new NDP */
1044 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1045 		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_max);
1046 
1047 	/* verify that there is room for the NDP and the datagram (reserve) */
1048 	if ((ctx->tx_max - skb->len - reserve) < ctx->max_ndp_size)
1049 		return NULL;
1050 
1051 	/* link to it */
1052 	if (ndp16)
1053 		ndp16->wNextNdpIndex = cpu_to_le16(skb->len);
1054 	else
1055 		nth16->wNdpIndex = cpu_to_le16(skb->len);
1056 
1057 	/* push a new empty NDP */
1058 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1059 		ndp16 = (struct usb_cdc_ncm_ndp16 *)memset(skb_put(skb, ctx->max_ndp_size), 0, ctx->max_ndp_size);
1060 	else
1061 		ndp16 = ctx->delayed_ndp16;
1062 
1063 	ndp16->dwSignature = sign;
1064 	ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
1065 	return ndp16;
1066 }
1067 
1068 struct sk_buff *
cdc_ncm_fill_tx_frame(struct usbnet * dev,struct sk_buff * skb,__le32 sign)1069 cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
1070 {
1071 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1072 	struct usb_cdc_ncm_nth16 *nth16;
1073 	struct usb_cdc_ncm_ndp16 *ndp16;
1074 	struct sk_buff *skb_out;
1075 	u16 n = 0, index, ndplen;
1076 	u8 ready2send = 0;
1077 	u32 delayed_ndp_size;
1078 	size_t padding_count;
1079 
1080 	/* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated
1081 	 * accordingly. Otherwise, we should check here.
1082 	 */
1083 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
1084 		delayed_ndp_size = ctx->max_ndp_size +
1085 			max_t(u32,
1086 			      ctx->tx_ndp_modulus,
1087 			      ctx->tx_modulus + ctx->tx_remainder) - 1;
1088 	else
1089 		delayed_ndp_size = 0;
1090 
1091 	/* if there is a remaining skb, it gets priority */
1092 	if (skb != NULL) {
1093 		swap(skb, ctx->tx_rem_skb);
1094 		swap(sign, ctx->tx_rem_sign);
1095 	} else {
1096 		ready2send = 1;
1097 	}
1098 
1099 	/* check if we are resuming an OUT skb */
1100 	skb_out = ctx->tx_curr_skb;
1101 
1102 	/* allocate a new OUT skb */
1103 	if (!skb_out) {
1104 		skb_out = alloc_skb(ctx->tx_max, GFP_ATOMIC);
1105 		if (skb_out == NULL) {
1106 			if (skb != NULL) {
1107 				dev_kfree_skb_any(skb);
1108 				dev->net->stats.tx_dropped++;
1109 			}
1110 			goto exit_no_skb;
1111 		}
1112 		/* fill out the initial 16-bit NTB header */
1113 		nth16 = (struct usb_cdc_ncm_nth16 *)memset(skb_put(skb_out, sizeof(struct usb_cdc_ncm_nth16)), 0, sizeof(struct usb_cdc_ncm_nth16));
1114 		nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
1115 		nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
1116 		nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
1117 
1118 		/* count total number of frames in this NTB */
1119 		ctx->tx_curr_frame_num = 0;
1120 
1121 		/* recent payload counter for this skb_out */
1122 		ctx->tx_curr_frame_payload = 0;
1123 	}
1124 
1125 	for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
1126 		/* send any remaining skb first */
1127 		if (skb == NULL) {
1128 			skb = ctx->tx_rem_skb;
1129 			sign = ctx->tx_rem_sign;
1130 			ctx->tx_rem_skb = NULL;
1131 
1132 			/* check for end of skb */
1133 			if (skb == NULL)
1134 				break;
1135 		}
1136 
1137 		/* get the appropriate NDP for this skb */
1138 		ndp16 = cdc_ncm_ndp(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1139 
1140 		/* align beginning of next frame */
1141 		cdc_ncm_align_tail(skb_out,  ctx->tx_modulus, ctx->tx_remainder, ctx->tx_max);
1142 
1143 		/* check if we had enough room left for both NDP and frame */
1144 		if (!ndp16 || skb_out->len + skb->len + delayed_ndp_size > ctx->tx_max) {
1145 			if (n == 0) {
1146 				/* won't fit, MTU problem? */
1147 				dev_kfree_skb_any(skb);
1148 				skb = NULL;
1149 				dev->net->stats.tx_dropped++;
1150 			} else {
1151 				/* no room for skb - store for later */
1152 				if (ctx->tx_rem_skb != NULL) {
1153 					dev_kfree_skb_any(ctx->tx_rem_skb);
1154 					dev->net->stats.tx_dropped++;
1155 				}
1156 				ctx->tx_rem_skb = skb;
1157 				ctx->tx_rem_sign = sign;
1158 				skb = NULL;
1159 				ready2send = 1;
1160 				ctx->tx_reason_ntb_full++;	/* count reason for transmitting */
1161 			}
1162 			break;
1163 		}
1164 
1165 		/* calculate frame number withing this NDP */
1166 		ndplen = le16_to_cpu(ndp16->wLength);
1167 		index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
1168 
1169 		/* OK, add this skb */
1170 		ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
1171 		ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
1172 		ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
1173 		memcpy(skb_put(skb_out, skb->len), skb->data, skb->len);
1174 		ctx->tx_curr_frame_payload += skb->len;	/* count real tx payload data */
1175 		dev_kfree_skb_any(skb);
1176 		skb = NULL;
1177 
1178 		/* send now if this NDP is full */
1179 		if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
1180 			ready2send = 1;
1181 			ctx->tx_reason_ndp_full++;	/* count reason for transmitting */
1182 			break;
1183 		}
1184 	}
1185 
1186 	/* free up any dangling skb */
1187 	if (skb != NULL) {
1188 		dev_kfree_skb_any(skb);
1189 		skb = NULL;
1190 		dev->net->stats.tx_dropped++;
1191 	}
1192 
1193 	ctx->tx_curr_frame_num = n;
1194 
1195 	if (n == 0) {
1196 		/* wait for more frames */
1197 		/* push variables */
1198 		ctx->tx_curr_skb = skb_out;
1199 		goto exit_no_skb;
1200 
1201 	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0) && (ctx->timer_interval > 0)) {
1202 		/* wait for more frames */
1203 		/* push variables */
1204 		ctx->tx_curr_skb = skb_out;
1205 		/* set the pending count */
1206 		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
1207 			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
1208 		goto exit_no_skb;
1209 
1210 	} else {
1211 		if (n == ctx->tx_max_datagrams)
1212 			ctx->tx_reason_max_datagram++;	/* count reason for transmitting */
1213 		/* frame goes out */
1214 		/* variables will be reset at next call */
1215 	}
1216 
1217 	/* If requested, put NDP at end of frame. */
1218 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1219 		nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1220 		cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_max - ctx->max_ndp_size);
1221 		nth16->wNdpIndex = cpu_to_le16(skb_out->len);
1222 		memcpy(skb_put(skb_out, ctx->max_ndp_size), ctx->delayed_ndp16, ctx->max_ndp_size);
1223 
1224 		/* Zero out delayed NDP - signature checking will naturally fail. */
1225 		ndp16 = memset(ctx->delayed_ndp16, 0, ctx->max_ndp_size);
1226 	}
1227 
1228 	/* If collected data size is less or equal ctx->min_tx_pkt
1229 	 * bytes, we send buffers as it is. If we get more data, it
1230 	 * would be more efficient for USB HS mobile device with DMA
1231 	 * engine to receive a full size NTB, than canceling DMA
1232 	 * transfer and receiving a short packet.
1233 	 *
1234 	 * This optimization support is pointless if we end up sending
1235 	 * a ZLP after full sized NTBs.
1236 	 */
1237 	if (!(dev->driver_info->flags & FLAG_SEND_ZLP) &&
1238 	    skb_out->len > ctx->min_tx_pkt) {
1239 		padding_count = ctx->tx_max - skb_out->len;
1240 		if (!WARN_ON(padding_count > ctx->tx_max))
1241 			memset(skb_put(skb_out, padding_count), 0, padding_count);
1242 	} else if (skb_out->len < ctx->tx_max &&
1243 		   (skb_out->len % dev->maxpacket) == 0) {
1244 		*skb_put(skb_out, 1) = 0;	/* force short packet */
1245 	}
1246 
1247 	/* set final frame length */
1248 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1249 	nth16->wBlockLength = cpu_to_le16(skb_out->len);
1250 
1251 	/* return skb */
1252 	ctx->tx_curr_skb = NULL;
1253 
1254 	/* keep private stats: framing overhead and number of NTBs */
1255 	ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
1256 	ctx->tx_ntbs++;
1257 
1258 	/* usbnet will count all the framing overhead by default.
1259 	 * Adjust the stats so that the tx_bytes counter show real
1260 	 * payload data instead.
1261 	 */
1262 	usbnet_set_skb_tx_stats(skb_out, n,
1263 				(long)ctx->tx_curr_frame_payload - skb_out->len);
1264 
1265 	return skb_out;
1266 
1267 exit_no_skb:
1268 	/* Start timer, if there is a remaining non-empty skb */
1269 	if (ctx->tx_curr_skb != NULL && n > 0)
1270 		cdc_ncm_tx_timeout_start(ctx);
1271 	return NULL;
1272 }
1273 EXPORT_SYMBOL_GPL(cdc_ncm_fill_tx_frame);
1274 
cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx * ctx)1275 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
1276 {
1277 	/* start timer, if not already started */
1278 	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
1279 		hrtimer_start(&ctx->tx_timer,
1280 				ktime_set(0, ctx->timer_interval),
1281 				HRTIMER_MODE_REL);
1282 }
1283 
cdc_ncm_tx_timer_cb(struct hrtimer * timer)1284 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
1285 {
1286 	struct cdc_ncm_ctx *ctx =
1287 			container_of(timer, struct cdc_ncm_ctx, tx_timer);
1288 
1289 	if (!atomic_read(&ctx->stop))
1290 		tasklet_schedule(&ctx->bh);
1291 	return HRTIMER_NORESTART;
1292 }
1293 
cdc_ncm_txpath_bh(unsigned long param)1294 static void cdc_ncm_txpath_bh(unsigned long param)
1295 {
1296 	struct usbnet *dev = (struct usbnet *)param;
1297 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1298 
1299 	spin_lock_bh(&ctx->mtx);
1300 	if (ctx->tx_timer_pending != 0) {
1301 		ctx->tx_timer_pending--;
1302 		cdc_ncm_tx_timeout_start(ctx);
1303 		spin_unlock_bh(&ctx->mtx);
1304 	} else if (dev->net != NULL) {
1305 		ctx->tx_reason_timeout++;	/* count reason for transmitting */
1306 		spin_unlock_bh(&ctx->mtx);
1307 		netif_tx_lock_bh(dev->net);
1308 		usbnet_start_xmit(NULL, dev->net);
1309 		netif_tx_unlock_bh(dev->net);
1310 	} else {
1311 		spin_unlock_bh(&ctx->mtx);
1312 	}
1313 }
1314 
1315 struct sk_buff *
cdc_ncm_tx_fixup(struct usbnet * dev,struct sk_buff * skb,gfp_t flags)1316 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
1317 {
1318 	struct sk_buff *skb_out;
1319 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1320 
1321 	/*
1322 	 * The Ethernet API we are using does not support transmitting
1323 	 * multiple Ethernet frames in a single call. This driver will
1324 	 * accumulate multiple Ethernet frames and send out a larger
1325 	 * USB frame when the USB buffer is full or when a single jiffies
1326 	 * timeout happens.
1327 	 */
1328 	if (ctx == NULL)
1329 		goto error;
1330 
1331 	spin_lock_bh(&ctx->mtx);
1332 	skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN));
1333 	spin_unlock_bh(&ctx->mtx);
1334 	return skb_out;
1335 
1336 error:
1337 	if (skb != NULL)
1338 		dev_kfree_skb_any(skb);
1339 
1340 	return NULL;
1341 }
1342 EXPORT_SYMBOL_GPL(cdc_ncm_tx_fixup);
1343 
1344 /* verify NTB header and return offset of first NDP, or negative error */
cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx * ctx,struct sk_buff * skb_in)1345 int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1346 {
1347 	struct usbnet *dev = netdev_priv(skb_in->dev);
1348 	struct usb_cdc_ncm_nth16 *nth16;
1349 	int len;
1350 	int ret = -EINVAL;
1351 
1352 	if (ctx == NULL)
1353 		goto error;
1354 
1355 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
1356 					sizeof(struct usb_cdc_ncm_ndp16))) {
1357 		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1358 		goto error;
1359 	}
1360 
1361 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
1362 
1363 	if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
1364 		netif_dbg(dev, rx_err, dev->net,
1365 			  "invalid NTH16 signature <%#010x>\n",
1366 			  le32_to_cpu(nth16->dwSignature));
1367 		goto error;
1368 	}
1369 
1370 	len = le16_to_cpu(nth16->wBlockLength);
1371 	if (len > ctx->rx_max) {
1372 		netif_dbg(dev, rx_err, dev->net,
1373 			  "unsupported NTB block length %u/%u\n", len,
1374 			  ctx->rx_max);
1375 		goto error;
1376 	}
1377 
1378 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
1379 	    (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
1380 	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
1381 		netif_dbg(dev, rx_err, dev->net,
1382 			  "sequence number glitch prev=%d curr=%d\n",
1383 			  ctx->rx_seq, le16_to_cpu(nth16->wSequence));
1384 	}
1385 	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
1386 
1387 	ret = le16_to_cpu(nth16->wNdpIndex);
1388 error:
1389 	return ret;
1390 }
1391 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth16);
1392 
1393 /* verify NDP header and return number of datagrams, or negative error */
cdc_ncm_rx_verify_ndp16(struct sk_buff * skb_in,int ndpoffset)1394 int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
1395 {
1396 	struct usbnet *dev = netdev_priv(skb_in->dev);
1397 	struct usb_cdc_ncm_ndp16 *ndp16;
1398 	int ret = -EINVAL;
1399 
1400 	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
1401 		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1402 			  ndpoffset);
1403 		goto error;
1404 	}
1405 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1406 
1407 	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1408 		netif_dbg(dev, rx_err, dev->net, "invalid DPT16 length <%u>\n",
1409 			  le16_to_cpu(ndp16->wLength));
1410 		goto error;
1411 	}
1412 
1413 	ret = ((le16_to_cpu(ndp16->wLength) -
1414 					sizeof(struct usb_cdc_ncm_ndp16)) /
1415 					sizeof(struct usb_cdc_ncm_dpe16));
1416 	ret--; /* we process NDP entries except for the last one */
1417 
1418 	if ((sizeof(struct usb_cdc_ncm_ndp16) +
1419 	     ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) {
1420 		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1421 		ret = -EINVAL;
1422 	}
1423 
1424 error:
1425 	return ret;
1426 }
1427 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp16);
1428 
cdc_ncm_rx_fixup(struct usbnet * dev,struct sk_buff * skb_in)1429 int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
1430 {
1431 	struct sk_buff *skb;
1432 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1433 	int len;
1434 	int nframes;
1435 	int x;
1436 	int offset;
1437 	struct usb_cdc_ncm_ndp16 *ndp16;
1438 	struct usb_cdc_ncm_dpe16 *dpe16;
1439 	int ndpoffset;
1440 	int loopcount = 50; /* arbitrary max preventing infinite loop */
1441 	u32 payload = 0;
1442 
1443 	ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
1444 	if (ndpoffset < 0)
1445 		goto error;
1446 
1447 next_ndp:
1448 	nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
1449 	if (nframes < 0)
1450 		goto error;
1451 
1452 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1453 
1454 	if (ndp16->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) {
1455 		netif_dbg(dev, rx_err, dev->net,
1456 			  "invalid DPT16 signature <%#010x>\n",
1457 			  le32_to_cpu(ndp16->dwSignature));
1458 		goto err_ndp;
1459 	}
1460 	dpe16 = ndp16->dpe16;
1461 
1462 	for (x = 0; x < nframes; x++, dpe16++) {
1463 		offset = le16_to_cpu(dpe16->wDatagramIndex);
1464 		len = le16_to_cpu(dpe16->wDatagramLength);
1465 
1466 		/*
1467 		 * CDC NCM ch. 3.7
1468 		 * All entries after first NULL entry are to be ignored
1469 		 */
1470 		if ((offset == 0) || (len == 0)) {
1471 			if (!x)
1472 				goto err_ndp; /* empty NTB */
1473 			break;
1474 		}
1475 
1476 		/* sanity checking */
1477 		if (((offset + len) > skb_in->len) ||
1478 				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1479 			netif_dbg(dev, rx_err, dev->net,
1480 				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
1481 				  x, offset, len, skb_in);
1482 			if (!x)
1483 				goto err_ndp;
1484 			break;
1485 
1486 		} else {
1487 			/* create a fresh copy to reduce truesize */
1488 			skb = netdev_alloc_skb_ip_align(dev->net,  len);
1489 			if (!skb)
1490 				goto error;
1491 			memcpy(skb_put(skb, len), skb_in->data + offset, len);
1492 			usbnet_skb_return(dev, skb);
1493 			payload += len;	/* count payload bytes in this NTB */
1494 		}
1495 	}
1496 err_ndp:
1497 	/* are there more NDPs to process? */
1498 	ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1499 	if (ndpoffset && loopcount--)
1500 		goto next_ndp;
1501 
1502 	/* update stats */
1503 	ctx->rx_overhead += skb_in->len - payload;
1504 	ctx->rx_ntbs++;
1505 
1506 	return 1;
1507 error:
1508 	return 0;
1509 }
1510 EXPORT_SYMBOL_GPL(cdc_ncm_rx_fixup);
1511 
1512 static void
cdc_ncm_speed_change(struct usbnet * dev,struct usb_cdc_speed_change * data)1513 cdc_ncm_speed_change(struct usbnet *dev,
1514 		     struct usb_cdc_speed_change *data)
1515 {
1516 	uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
1517 	uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
1518 
1519 	/*
1520 	 * Currently the USB-NET API does not support reporting the actual
1521 	 * device speed. Do print it instead.
1522 	 */
1523 	if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
1524 		netif_info(dev, link, dev->net,
1525 			   "%u mbit/s downlink %u mbit/s uplink\n",
1526 			   (unsigned int)(rx_speed / 1000000U),
1527 			   (unsigned int)(tx_speed / 1000000U));
1528 	} else {
1529 		netif_info(dev, link, dev->net,
1530 			   "%u kbit/s downlink %u kbit/s uplink\n",
1531 			   (unsigned int)(rx_speed / 1000U),
1532 			   (unsigned int)(tx_speed / 1000U));
1533 	}
1534 }
1535 
cdc_ncm_status(struct usbnet * dev,struct urb * urb)1536 static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1537 {
1538 	struct cdc_ncm_ctx *ctx;
1539 	struct usb_cdc_notification *event;
1540 
1541 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1542 
1543 	if (urb->actual_length < sizeof(*event))
1544 		return;
1545 
1546 	/* test for split data in 8-byte chunks */
1547 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1548 		cdc_ncm_speed_change(dev,
1549 		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1550 		return;
1551 	}
1552 
1553 	event = urb->transfer_buffer;
1554 
1555 	switch (event->bNotificationType) {
1556 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1557 		/*
1558 		 * According to the CDC NCM specification ch.7.1
1559 		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1560 		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1561 		 */
1562 		usbnet_link_change(dev, !!event->wValue, 0);
1563 		break;
1564 
1565 	case USB_CDC_NOTIFY_SPEED_CHANGE:
1566 		if (urb->actual_length < (sizeof(*event) +
1567 					sizeof(struct usb_cdc_speed_change)))
1568 			set_bit(EVENT_STS_SPLIT, &dev->flags);
1569 		else
1570 			cdc_ncm_speed_change(dev,
1571 					     (struct usb_cdc_speed_change *)&event[1]);
1572 		break;
1573 
1574 	default:
1575 		dev_dbg(&dev->udev->dev,
1576 			"NCM: unexpected notification 0x%02x!\n",
1577 			event->bNotificationType);
1578 		break;
1579 	}
1580 }
1581 
1582 static const struct driver_info cdc_ncm_info = {
1583 	.description = "CDC NCM",
1584 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1585 			| FLAG_LINK_INTR | FLAG_ETHER,
1586 	.bind = cdc_ncm_bind,
1587 	.unbind = cdc_ncm_unbind,
1588 	.manage_power = usbnet_manage_power,
1589 	.status = cdc_ncm_status,
1590 	.rx_fixup = cdc_ncm_rx_fixup,
1591 	.tx_fixup = cdc_ncm_tx_fixup,
1592 };
1593 
1594 /* Same as cdc_ncm_info, but with FLAG_WWAN */
1595 static const struct driver_info wwan_info = {
1596 	.description = "Mobile Broadband Network Device",
1597 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1598 			| FLAG_LINK_INTR | FLAG_WWAN,
1599 	.bind = cdc_ncm_bind,
1600 	.unbind = cdc_ncm_unbind,
1601 	.manage_power = usbnet_manage_power,
1602 	.status = cdc_ncm_status,
1603 	.rx_fixup = cdc_ncm_rx_fixup,
1604 	.tx_fixup = cdc_ncm_tx_fixup,
1605 };
1606 
1607 /* Same as wwan_info, but with FLAG_NOARP  */
1608 static const struct driver_info wwan_noarp_info = {
1609 	.description = "Mobile Broadband Network Device (NO ARP)",
1610 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1611 			| FLAG_LINK_INTR | FLAG_WWAN | FLAG_NOARP,
1612 	.bind = cdc_ncm_bind,
1613 	.unbind = cdc_ncm_unbind,
1614 	.manage_power = usbnet_manage_power,
1615 	.status = cdc_ncm_status,
1616 	.rx_fixup = cdc_ncm_rx_fixup,
1617 	.tx_fixup = cdc_ncm_tx_fixup,
1618 };
1619 
1620 static const struct usb_device_id cdc_devs[] = {
1621 	/* Ericsson MBM devices like F5521gw */
1622 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1623 		| USB_DEVICE_ID_MATCH_VENDOR,
1624 	  .idVendor = 0x0bdb,
1625 	  .bInterfaceClass = USB_CLASS_COMM,
1626 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1627 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1628 	  .driver_info = (unsigned long) &wwan_info,
1629 	},
1630 
1631 	/* DW5812 LTE Verizon Mobile Broadband Card
1632 	 * Unlike DW5550 this device requires FLAG_NOARP
1633 	 */
1634 	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bb,
1635 		USB_CLASS_COMM,
1636 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1637 	  .driver_info = (unsigned long)&wwan_noarp_info,
1638 	},
1639 
1640 	/* DW5813 LTE AT&T Mobile Broadband Card
1641 	 * Unlike DW5550 this device requires FLAG_NOARP
1642 	 */
1643 	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bc,
1644 		USB_CLASS_COMM,
1645 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1646 	  .driver_info = (unsigned long)&wwan_noarp_info,
1647 	},
1648 
1649 	/* Dell branded MBM devices like DW5550 */
1650 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1651 		| USB_DEVICE_ID_MATCH_VENDOR,
1652 	  .idVendor = 0x413c,
1653 	  .bInterfaceClass = USB_CLASS_COMM,
1654 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1655 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1656 	  .driver_info = (unsigned long) &wwan_info,
1657 	},
1658 
1659 	/* Toshiba branded MBM devices */
1660 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1661 		| USB_DEVICE_ID_MATCH_VENDOR,
1662 	  .idVendor = 0x0930,
1663 	  .bInterfaceClass = USB_CLASS_COMM,
1664 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1665 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1666 	  .driver_info = (unsigned long) &wwan_info,
1667 	},
1668 
1669 	/* tag Huawei devices as wwan */
1670 	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1,
1671 					USB_CLASS_COMM,
1672 					USB_CDC_SUBCLASS_NCM,
1673 					USB_CDC_PROTO_NONE),
1674 	  .driver_info = (unsigned long)&wwan_info,
1675 	},
1676 
1677 	/* Infineon(now Intel) HSPA Modem platform */
1678 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1519, 0x0443,
1679 		USB_CLASS_COMM,
1680 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1681 	  .driver_info = (unsigned long)&wwan_noarp_info,
1682 	},
1683 
1684 	/* Generic CDC-NCM devices */
1685 	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
1686 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1687 		.driver_info = (unsigned long)&cdc_ncm_info,
1688 	},
1689 	{
1690 	},
1691 };
1692 MODULE_DEVICE_TABLE(usb, cdc_devs);
1693 
1694 static struct usb_driver cdc_ncm_driver = {
1695 	.name = "cdc_ncm",
1696 	.id_table = cdc_devs,
1697 	.probe = usbnet_probe,
1698 	.disconnect = usbnet_disconnect,
1699 	.suspend = usbnet_suspend,
1700 	.resume = usbnet_resume,
1701 	.reset_resume =	usbnet_resume,
1702 	.supports_autosuspend = 1,
1703 	.disable_hub_initiated_lpm = 1,
1704 };
1705 
1706 module_usb_driver(cdc_ncm_driver);
1707 
1708 MODULE_AUTHOR("Hans Petter Selasky");
1709 MODULE_DESCRIPTION("USB CDC NCM host driver");
1710 MODULE_LICENSE("Dual BSD/GPL");
1711