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)
57static bool prefer_mbim = true;
58#else
59static bool prefer_mbim;
60#endif
61module_param(prefer_mbim, bool, 0644);
62MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
63
64static void cdc_ncm_txpath_bh(unsigned long param);
65static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
66static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
67static struct usb_driver cdc_ncm_driver;
68
69struct 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
81static 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
92#define CDC_NCM_LOW_MEM_MAX_CNT 10
93
94static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset)
95{
96	switch (sset) {
97	case ETH_SS_STATS:
98		return ARRAY_SIZE(cdc_ncm_gstrings_stats);
99	default:
100		return -EOPNOTSUPP;
101	}
102}
103
104static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
105				    struct ethtool_stats __always_unused *stats,
106				    u64 *data)
107{
108	struct usbnet *dev = netdev_priv(netdev);
109	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
110	int i;
111	char *p = NULL;
112
113	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
114		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
115		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
116	}
117}
118
119static void cdc_ncm_get_strings(struct net_device __always_unused *netdev, u32 stringset, u8 *data)
120{
121	u8 *p = data;
122	int i;
123
124	switch (stringset) {
125	case ETH_SS_STATS:
126		for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
127			memcpy(p, cdc_ncm_gstrings_stats[i].stat_string, ETH_GSTRING_LEN);
128			p += ETH_GSTRING_LEN;
129		}
130	}
131}
132
133static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx);
134
135static const struct ethtool_ops cdc_ncm_ethtool_ops = {
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	.get_link_ksettings      = usbnet_get_link_ksettings,
146	.set_link_ksettings      = usbnet_set_link_ksettings,
147};
148
149static u32 cdc_ncm_check_rx_max(struct usbnet *dev, u32 new_rx)
150{
151	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
152	u32 val, max, min;
153
154	/* clamp new_rx to sane values */
155	min = USB_CDC_NCM_NTB_MIN_IN_SIZE;
156	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_RX, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
157
158	/* dwNtbInMaxSize spec violation? Use MIN size for both limits */
159	if (max < min) {
160		dev_warn(&dev->intf->dev, "dwNtbInMaxSize=%u is too small. Using %u\n",
161			 le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize), min);
162		max = min;
163	}
164
165	val = clamp_t(u32, new_rx, min, max);
166	if (val != new_rx)
167		dev_dbg(&dev->intf->dev, "rx_max must be in the [%u, %u] range\n", min, max);
168
169	return val;
170}
171
172static u32 cdc_ncm_check_tx_max(struct usbnet *dev, u32 new_tx)
173{
174	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
175	u32 val, max, min;
176
177	/* clamp new_tx to sane values */
178	if (ctx->is_ndp16)
179		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth16);
180	else
181		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth32);
182
183	if (le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) == 0)
184		max = CDC_NCM_NTB_MAX_SIZE_TX; /* dwNtbOutMaxSize not set */
185	else
186		max = clamp_t(u32, le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize),
187			      USB_CDC_NCM_NTB_MIN_OUT_SIZE,
188			      CDC_NCM_NTB_MAX_SIZE_TX);
189
190	/* some devices set dwNtbOutMaxSize too low for the above default */
191	min = min(min, max);
192
193	val = clamp_t(u32, new_tx, min, max);
194	if (val != new_tx)
195		dev_dbg(&dev->intf->dev, "tx_max must be in the [%u, %u] range\n", min, max);
196
197	return val;
198}
199
200static ssize_t cdc_ncm_show_min_tx_pkt(struct device *d, struct device_attribute *attr, char *buf)
201{
202	struct usbnet *dev = netdev_priv(to_net_dev(d));
203	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
204
205	return sprintf(buf, "%u\n", ctx->min_tx_pkt);
206}
207
208static ssize_t cdc_ncm_show_rx_max(struct device *d, struct device_attribute *attr, char *buf)
209{
210	struct usbnet *dev = netdev_priv(to_net_dev(d));
211	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
212
213	return sprintf(buf, "%u\n", ctx->rx_max);
214}
215
216static ssize_t cdc_ncm_show_tx_max(struct device *d, struct device_attribute *attr, char *buf)
217{
218	struct usbnet *dev = netdev_priv(to_net_dev(d));
219	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
220
221	return sprintf(buf, "%u\n", ctx->tx_max);
222}
223
224static ssize_t cdc_ncm_show_tx_timer_usecs(struct device *d, struct device_attribute *attr, char *buf)
225{
226	struct usbnet *dev = netdev_priv(to_net_dev(d));
227	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
228
229	return sprintf(buf, "%u\n", ctx->timer_interval / (u32)NSEC_PER_USEC);
230}
231
232static ssize_t cdc_ncm_store_min_tx_pkt(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
233{
234	struct usbnet *dev = netdev_priv(to_net_dev(d));
235	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
236	unsigned long val;
237
238	/* no need to restrict values - anything from 0 to infinity is OK */
239	if (kstrtoul(buf, 0, &val))
240		return -EINVAL;
241
242	ctx->min_tx_pkt = val;
243	return len;
244}
245
246static ssize_t cdc_ncm_store_rx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
247{
248	struct usbnet *dev = netdev_priv(to_net_dev(d));
249	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
250	unsigned long val;
251
252	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_rx_max(dev, val) != val)
253		return -EINVAL;
254
255	cdc_ncm_update_rxtx_max(dev, val, ctx->tx_max);
256	return len;
257}
258
259static ssize_t cdc_ncm_store_tx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
260{
261	struct usbnet *dev = netdev_priv(to_net_dev(d));
262	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
263	unsigned long val;
264
265	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_tx_max(dev, val) != val)
266		return -EINVAL;
267
268	cdc_ncm_update_rxtx_max(dev, ctx->rx_max, val);
269	return len;
270}
271
272static ssize_t cdc_ncm_store_tx_timer_usecs(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
273{
274	struct usbnet *dev = netdev_priv(to_net_dev(d));
275	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
276	ssize_t ret;
277	unsigned long val;
278
279	ret = kstrtoul(buf, 0, &val);
280	if (ret)
281		return ret;
282	if (val && (val < CDC_NCM_TIMER_INTERVAL_MIN || val > CDC_NCM_TIMER_INTERVAL_MAX))
283		return -EINVAL;
284
285	spin_lock_bh(&ctx->mtx);
286	ctx->timer_interval = val * NSEC_PER_USEC;
287	if (!ctx->timer_interval)
288		ctx->tx_timer_pending = 0;
289	spin_unlock_bh(&ctx->mtx);
290	return len;
291}
292
293static DEVICE_ATTR(min_tx_pkt, 0644, cdc_ncm_show_min_tx_pkt, cdc_ncm_store_min_tx_pkt);
294static DEVICE_ATTR(rx_max, 0644, cdc_ncm_show_rx_max, cdc_ncm_store_rx_max);
295static DEVICE_ATTR(tx_max, 0644, cdc_ncm_show_tx_max, cdc_ncm_store_tx_max);
296static DEVICE_ATTR(tx_timer_usecs, 0644, cdc_ncm_show_tx_timer_usecs, cdc_ncm_store_tx_timer_usecs);
297
298static ssize_t ndp_to_end_show(struct device *d, struct device_attribute *attr, char *buf)
299{
300	struct usbnet *dev = netdev_priv(to_net_dev(d));
301	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
302
303	return sprintf(buf, "%c\n", ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END ? 'Y' : 'N');
304}
305
306static ssize_t ndp_to_end_store(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
307{
308	struct usbnet *dev = netdev_priv(to_net_dev(d));
309	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
310	bool enable;
311
312	if (strtobool(buf, &enable))
313		return -EINVAL;
314
315	/* no change? */
316	if (enable == (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
317		return len;
318
319	if (enable) {
320		if (ctx->is_ndp16 && !ctx->delayed_ndp16) {
321			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
322			if (!ctx->delayed_ndp16)
323				return -ENOMEM;
324		}
325		if (!ctx->is_ndp16 && !ctx->delayed_ndp32) {
326			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
327			if (!ctx->delayed_ndp32)
328				return -ENOMEM;
329		}
330	}
331
332	/* flush pending data before changing flag */
333	netif_tx_lock_bh(dev->net);
334	usbnet_start_xmit(NULL, dev->net);
335	spin_lock_bh(&ctx->mtx);
336	if (enable)
337		ctx->drvflags |= CDC_NCM_FLAG_NDP_TO_END;
338	else
339		ctx->drvflags &= ~CDC_NCM_FLAG_NDP_TO_END;
340	spin_unlock_bh(&ctx->mtx);
341	netif_tx_unlock_bh(dev->net);
342
343	return len;
344}
345static DEVICE_ATTR_RW(ndp_to_end);
346
347#define NCM_PARM_ATTR(name, format, tocpu)				\
348static ssize_t cdc_ncm_show_##name(struct device *d, struct device_attribute *attr, char *buf) \
349{ \
350	struct usbnet *dev = netdev_priv(to_net_dev(d)); \
351	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; \
352	return sprintf(buf, format "\n", tocpu(ctx->ncm_parm.name));	\
353} \
354static DEVICE_ATTR(name, 0444, cdc_ncm_show_##name, NULL)
355
356NCM_PARM_ATTR(bmNtbFormatsSupported, "0x%04x", le16_to_cpu);
357NCM_PARM_ATTR(dwNtbInMaxSize, "%u", le32_to_cpu);
358NCM_PARM_ATTR(wNdpInDivisor, "%u", le16_to_cpu);
359NCM_PARM_ATTR(wNdpInPayloadRemainder, "%u", le16_to_cpu);
360NCM_PARM_ATTR(wNdpInAlignment, "%u", le16_to_cpu);
361NCM_PARM_ATTR(dwNtbOutMaxSize, "%u", le32_to_cpu);
362NCM_PARM_ATTR(wNdpOutDivisor, "%u", le16_to_cpu);
363NCM_PARM_ATTR(wNdpOutPayloadRemainder, "%u", le16_to_cpu);
364NCM_PARM_ATTR(wNdpOutAlignment, "%u", le16_to_cpu);
365NCM_PARM_ATTR(wNtbOutMaxDatagrams, "%u", le16_to_cpu);
366
367static struct attribute *cdc_ncm_sysfs_attrs[] = {
368	&dev_attr_min_tx_pkt.attr,
369	&dev_attr_ndp_to_end.attr,
370	&dev_attr_rx_max.attr,
371	&dev_attr_tx_max.attr,
372	&dev_attr_tx_timer_usecs.attr,
373	&dev_attr_bmNtbFormatsSupported.attr,
374	&dev_attr_dwNtbInMaxSize.attr,
375	&dev_attr_wNdpInDivisor.attr,
376	&dev_attr_wNdpInPayloadRemainder.attr,
377	&dev_attr_wNdpInAlignment.attr,
378	&dev_attr_dwNtbOutMaxSize.attr,
379	&dev_attr_wNdpOutDivisor.attr,
380	&dev_attr_wNdpOutPayloadRemainder.attr,
381	&dev_attr_wNdpOutAlignment.attr,
382	&dev_attr_wNtbOutMaxDatagrams.attr,
383	NULL,
384};
385
386static const struct attribute_group cdc_ncm_sysfs_attr_group = {
387	.name = "cdc_ncm",
388	.attrs = cdc_ncm_sysfs_attrs,
389};
390
391/* handle rx_max and tx_max changes */
392static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx)
393{
394	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
395	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
396	u32 val;
397
398	val = cdc_ncm_check_rx_max(dev, new_rx);
399
400	/* inform device about NTB input size changes */
401	if (val != ctx->rx_max) {
402		__le32 dwNtbInMaxSize = cpu_to_le32(val);
403
404		dev_info(&dev->intf->dev, "setting rx_max = %u\n", val);
405
406		/* tell device to use new size */
407		if (usbnet_write_cmd(dev, USB_CDC_SET_NTB_INPUT_SIZE,
408				     USB_TYPE_CLASS | USB_DIR_OUT
409				     | USB_RECIP_INTERFACE,
410				     0, iface_no, &dwNtbInMaxSize, 4) < 0)
411			dev_dbg(&dev->intf->dev, "Setting NTB Input Size failed\n");
412		else
413			ctx->rx_max = val;
414	}
415
416	/* usbnet use these values for sizing rx queues */
417	if (dev->rx_urb_size != ctx->rx_max) {
418		dev->rx_urb_size = ctx->rx_max;
419		if (netif_running(dev->net))
420			usbnet_unlink_rx_urbs(dev);
421	}
422
423	val = cdc_ncm_check_tx_max(dev, new_tx);
424	if (val != ctx->tx_max)
425		dev_info(&dev->intf->dev, "setting tx_max = %u\n", val);
426
427	/* Adding a pad byte here if necessary simplifies the handling
428	 * in cdc_ncm_fill_tx_frame, making tx_max always represent
429	 * the real skb max size.
430	 *
431	 * We cannot use dev->maxpacket here because this is called from
432	 * .bind which is called before usbnet sets up dev->maxpacket
433	 */
434	if (val != le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) &&
435	    val % usb_maxpacket(dev->udev, dev->out, 1) == 0)
436		val++;
437
438	/* we might need to flush any pending tx buffers if running */
439	if (netif_running(dev->net) && val > ctx->tx_max) {
440		netif_tx_lock_bh(dev->net);
441		usbnet_start_xmit(NULL, dev->net);
442		/* make sure tx_curr_skb is reallocated if it was empty */
443		if (ctx->tx_curr_skb) {
444			dev_kfree_skb_any(ctx->tx_curr_skb);
445			ctx->tx_curr_skb = NULL;
446		}
447		ctx->tx_max = val;
448		netif_tx_unlock_bh(dev->net);
449	} else {
450		ctx->tx_max = val;
451	}
452
453	dev->hard_mtu = ctx->tx_max;
454
455	/* max qlen depend on hard_mtu and rx_urb_size */
456	usbnet_update_max_qlen(dev);
457
458	/* never pad more than 3 full USB packets per transfer */
459	ctx->min_tx_pkt = clamp_t(u16, ctx->tx_max - 3 * usb_maxpacket(dev->udev, dev->out, 1),
460				  CDC_NCM_MIN_TX_PKT, ctx->tx_max);
461}
462
463/* helpers for NCM and MBIM differences */
464static u8 cdc_ncm_flags(struct usbnet *dev)
465{
466	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
467
468	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
469		return ctx->mbim_desc->bmNetworkCapabilities;
470	if (ctx->func_desc)
471		return ctx->func_desc->bmNetworkCapabilities;
472	return 0;
473}
474
475static int cdc_ncm_eth_hlen(struct usbnet *dev)
476{
477	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
478		return 0;
479	return ETH_HLEN;
480}
481
482static u32 cdc_ncm_min_dgram_size(struct usbnet *dev)
483{
484	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
485		return CDC_MBIM_MIN_DATAGRAM_SIZE;
486	return CDC_NCM_MIN_DATAGRAM_SIZE;
487}
488
489static u32 cdc_ncm_max_dgram_size(struct usbnet *dev)
490{
491	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
492
493	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
494		return le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
495	if (ctx->ether_desc)
496		return le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
497	return CDC_NCM_MAX_DATAGRAM_SIZE;
498}
499
500/* initial one-time device setup.  MUST be called with the data interface
501 * in altsetting 0
502 */
503static int cdc_ncm_init(struct usbnet *dev)
504{
505	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
506	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
507	int err;
508
509	err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
510			      USB_TYPE_CLASS | USB_DIR_IN
511			      |USB_RECIP_INTERFACE,
512			      0, iface_no, &ctx->ncm_parm,
513			      sizeof(ctx->ncm_parm));
514	if (err < 0) {
515		dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
516		return err; /* GET_NTB_PARAMETERS is required */
517	}
518
519	/* set CRC Mode */
520	if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
521		dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
522		err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
523				       USB_TYPE_CLASS | USB_DIR_OUT
524				       | USB_RECIP_INTERFACE,
525				       USB_CDC_NCM_CRC_NOT_APPENDED,
526				       iface_no, NULL, 0);
527		if (err < 0)
528			dev_err(&dev->intf->dev, "SET_CRC_MODE failed\n");
529	}
530
531	/* use ndp16 by default */
532	ctx->is_ndp16 = 1;
533
534	/* set NTB format, if both formats are supported.
535	 *
536	 * "The host shall only send this command while the NCM Data
537	 *  Interface is in alternate setting 0."
538	 */
539	if (le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported) &
540						USB_CDC_NCM_NTB32_SUPPORTED) {
541		if (ctx->drvflags & CDC_NCM_FLAG_PREFER_NTB32) {
542			ctx->is_ndp16 = 0;
543			dev_dbg(&dev->intf->dev, "Setting NTB format to 32-bit\n");
544			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
545					       USB_TYPE_CLASS | USB_DIR_OUT
546					       | USB_RECIP_INTERFACE,
547					       USB_CDC_NCM_NTB32_FORMAT,
548					       iface_no, NULL, 0);
549		} else {
550			ctx->is_ndp16 = 1;
551			dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit\n");
552			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
553					       USB_TYPE_CLASS | USB_DIR_OUT
554					       | USB_RECIP_INTERFACE,
555					       USB_CDC_NCM_NTB16_FORMAT,
556					       iface_no, NULL, 0);
557		}
558		if (err < 0) {
559			ctx->is_ndp16 = 1;
560			dev_err(&dev->intf->dev, "SET_NTB_FORMAT failed\n");
561		}
562	}
563
564	/* set initial device values */
565	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
566	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
567	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
568	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
569	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
570	/* devices prior to NCM Errata shall set this field to zero */
571	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
572
573	dev_dbg(&dev->intf->dev,
574		"dwNtbInMaxSize=%u dwNtbOutMaxSize=%u wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
575		ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
576		ctx->tx_ndp_modulus, ctx->tx_max_datagrams, cdc_ncm_flags(dev));
577
578	/* max count of tx datagrams */
579	if ((ctx->tx_max_datagrams == 0) ||
580			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
581		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
582
583	/* set up maximum NDP size */
584	if (ctx->is_ndp16)
585		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp16) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe16);
586	else
587		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp32) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe32);
588
589	/* initial coalescing timer interval */
590	ctx->timer_interval = CDC_NCM_TIMER_INTERVAL_USEC * NSEC_PER_USEC;
591
592	return 0;
593}
594
595/* set a new max datagram size */
596static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
597{
598	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
599	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
600	__le16 max_datagram_size;
601	u16 mbim_mtu;
602	int err;
603
604	/* set default based on descriptors */
605	ctx->max_datagram_size = clamp_t(u32, new_size,
606					 cdc_ncm_min_dgram_size(dev),
607					 CDC_NCM_MAX_DATAGRAM_SIZE);
608
609	/* inform the device about the selected Max Datagram Size? */
610	if (!(cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
611		goto out;
612
613	/* read current mtu value from device */
614	err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
615			      USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
616			      0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
617	if (err != sizeof(max_datagram_size)) {
618		dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
619		goto out;
620	}
621
622	if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
623		goto out;
624
625	max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
626	err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
627			       USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
628			       0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
629	if (err < 0)
630		dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
631
632out:
633	/* set MTU to max supported by the device if necessary */
634	dev->net->mtu = min_t(int, dev->net->mtu, ctx->max_datagram_size - cdc_ncm_eth_hlen(dev));
635
636	/* do not exceed operater preferred MTU */
637	if (ctx->mbim_extended_desc) {
638		mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
639		if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
640			dev->net->mtu = mbim_mtu;
641	}
642}
643
644static void cdc_ncm_fix_modulus(struct usbnet *dev)
645{
646	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
647	u32 val;
648
649	/*
650	 * verify that the structure alignment is:
651	 * - power of two
652	 * - not greater than the maximum transmit length
653	 * - not less than four bytes
654	 */
655	val = ctx->tx_ndp_modulus;
656
657	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
658	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
659		dev_dbg(&dev->intf->dev, "Using default alignment: 4 bytes\n");
660		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
661	}
662
663	/*
664	 * verify that the payload alignment is:
665	 * - power of two
666	 * - not greater than the maximum transmit length
667	 * - not less than four bytes
668	 */
669	val = ctx->tx_modulus;
670
671	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
672	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
673		dev_dbg(&dev->intf->dev, "Using default transmit modulus: 4 bytes\n");
674		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
675	}
676
677	/* verify the payload remainder */
678	if (ctx->tx_remainder >= ctx->tx_modulus) {
679		dev_dbg(&dev->intf->dev, "Using default transmit remainder: 0 bytes\n");
680		ctx->tx_remainder = 0;
681	}
682
683	/* adjust TX-remainder according to NCM specification. */
684	ctx->tx_remainder = ((ctx->tx_remainder - cdc_ncm_eth_hlen(dev)) &
685			     (ctx->tx_modulus - 1));
686}
687
688static int cdc_ncm_setup(struct usbnet *dev)
689{
690	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
691	u32 def_rx, def_tx;
692
693	/* be conservative when selecting intial buffer size to
694	 * increase the number of hosts this will work for
695	 */
696	def_rx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_RX,
697		       le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
698	def_tx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_TX,
699		       le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
700
701	/* clamp rx_max and tx_max and inform device */
702	cdc_ncm_update_rxtx_max(dev, def_rx, def_tx);
703
704	/* sanitize the modulus and remainder values */
705	cdc_ncm_fix_modulus(dev);
706
707	/* set max datagram size */
708	cdc_ncm_set_dgram_size(dev, cdc_ncm_max_dgram_size(dev));
709	return 0;
710}
711
712static void
713cdc_ncm_find_endpoints(struct usbnet *dev, struct usb_interface *intf)
714{
715	struct usb_host_endpoint *e, *in = NULL, *out = NULL;
716	u8 ep;
717
718	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
719		e = intf->cur_altsetting->endpoint + ep;
720
721		/* ignore endpoints which cannot transfer data */
722		if (!usb_endpoint_maxp(&e->desc))
723			continue;
724
725		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
726		case USB_ENDPOINT_XFER_INT:
727			if (usb_endpoint_dir_in(&e->desc)) {
728				if (!dev->status)
729					dev->status = e;
730			}
731			break;
732
733		case USB_ENDPOINT_XFER_BULK:
734			if (usb_endpoint_dir_in(&e->desc)) {
735				if (!in)
736					in = e;
737			} else {
738				if (!out)
739					out = e;
740			}
741			break;
742
743		default:
744			break;
745		}
746	}
747	if (in && !dev->in)
748		dev->in = usb_rcvbulkpipe(dev->udev,
749					  in->desc.bEndpointAddress &
750					  USB_ENDPOINT_NUMBER_MASK);
751	if (out && !dev->out)
752		dev->out = usb_sndbulkpipe(dev->udev,
753					   out->desc.bEndpointAddress &
754					   USB_ENDPOINT_NUMBER_MASK);
755}
756
757static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
758{
759	if (ctx == NULL)
760		return;
761
762	if (ctx->tx_rem_skb != NULL) {
763		dev_kfree_skb_any(ctx->tx_rem_skb);
764		ctx->tx_rem_skb = NULL;
765	}
766
767	if (ctx->tx_curr_skb != NULL) {
768		dev_kfree_skb_any(ctx->tx_curr_skb);
769		ctx->tx_curr_skb = NULL;
770	}
771
772	if (ctx->is_ndp16)
773		kfree(ctx->delayed_ndp16);
774	else
775		kfree(ctx->delayed_ndp32);
776
777	kfree(ctx);
778}
779
780/* we need to override the usbnet change_mtu ndo for two reasons:
781 *  - respect the negotiated maximum datagram size
782 *  - avoid unwanted changes to rx and tx buffers
783 */
784int cdc_ncm_change_mtu(struct net_device *net, int new_mtu)
785{
786	struct usbnet *dev = netdev_priv(net);
787
788	net->mtu = new_mtu;
789	cdc_ncm_set_dgram_size(dev, new_mtu + cdc_ncm_eth_hlen(dev));
790
791	return 0;
792}
793EXPORT_SYMBOL_GPL(cdc_ncm_change_mtu);
794
795static const struct net_device_ops cdc_ncm_netdev_ops = {
796	.ndo_open	     = usbnet_open,
797	.ndo_stop	     = usbnet_stop,
798	.ndo_start_xmit	     = usbnet_start_xmit,
799	.ndo_tx_timeout	     = usbnet_tx_timeout,
800	.ndo_set_rx_mode     = usbnet_set_rx_mode,
801	.ndo_get_stats64     = usbnet_get_stats64,
802	.ndo_change_mtu	     = cdc_ncm_change_mtu,
803	.ndo_set_mac_address = eth_mac_addr,
804	.ndo_validate_addr   = eth_validate_addr,
805};
806
807int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting, int drvflags)
808{
809	struct cdc_ncm_ctx *ctx;
810	struct usb_driver *driver;
811	u8 *buf;
812	int len;
813	int temp;
814	u8 iface_no;
815	struct usb_cdc_parsed_header hdr;
816
817	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
818	if (!ctx)
819		return -ENOMEM;
820
821	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
822	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
823	tasklet_init(&ctx->bh, cdc_ncm_txpath_bh, (unsigned long)dev);
824	atomic_set(&ctx->stop, 0);
825	spin_lock_init(&ctx->mtx);
826
827	/* store ctx pointer in device data field */
828	dev->data[0] = (unsigned long)ctx;
829
830	/* only the control interface can be successfully probed */
831	ctx->control = intf;
832
833	/* get some pointers */
834	driver = driver_of(intf);
835	buf = intf->cur_altsetting->extra;
836	len = intf->cur_altsetting->extralen;
837
838	/* parse through descriptors associated with control interface */
839	cdc_parse_cdc_header(&hdr, intf, buf, len);
840
841	if (hdr.usb_cdc_union_desc)
842		ctx->data = usb_ifnum_to_if(dev->udev,
843					    hdr.usb_cdc_union_desc->bSlaveInterface0);
844	ctx->ether_desc = hdr.usb_cdc_ether_desc;
845	ctx->func_desc = hdr.usb_cdc_ncm_desc;
846	ctx->mbim_desc = hdr.usb_cdc_mbim_desc;
847	ctx->mbim_extended_desc = hdr.usb_cdc_mbim_extended_desc;
848
849	/* some buggy devices have an IAD but no CDC Union */
850	if (!hdr.usb_cdc_union_desc && intf->intf_assoc && intf->intf_assoc->bInterfaceCount == 2) {
851		ctx->data = usb_ifnum_to_if(dev->udev, intf->cur_altsetting->desc.bInterfaceNumber + 1);
852		dev_dbg(&intf->dev, "CDC Union missing - got slave from IAD\n");
853	}
854
855	/* check if we got everything */
856	if (!ctx->data) {
857		dev_dbg(&intf->dev, "CDC Union missing and no IAD found\n");
858		goto error;
859	}
860	if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) {
861		if (!ctx->mbim_desc) {
862			dev_dbg(&intf->dev, "MBIM functional descriptor missing\n");
863			goto error;
864		}
865	} else {
866		if (!ctx->ether_desc || !ctx->func_desc) {
867			dev_dbg(&intf->dev, "NCM or ECM functional descriptors missing\n");
868			goto error;
869		}
870	}
871
872	/* claim data interface, if different from control */
873	if (ctx->data != ctx->control) {
874		temp = usb_driver_claim_interface(driver, ctx->data, dev);
875		if (temp) {
876			dev_dbg(&intf->dev, "failed to claim data intf\n");
877			goto error;
878		}
879	}
880
881	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
882
883	/* Device-specific flags */
884	ctx->drvflags = drvflags;
885
886	/* Reset data interface. Some devices will not reset properly
887	 * unless they are configured first.  Toggle the altsetting to
888	 * force a reset.
889	 * Some other devices do not work properly with this procedure
890	 * that can be avoided using quirk CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE
891	 */
892	if (!(ctx->drvflags & CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE))
893		usb_set_interface(dev->udev, iface_no, data_altsetting);
894
895	temp = usb_set_interface(dev->udev, iface_no, 0);
896	if (temp) {
897		dev_dbg(&intf->dev, "set interface failed\n");
898		goto error2;
899	}
900
901	/* initialize basic device settings */
902	if (cdc_ncm_init(dev))
903		goto error2;
904
905	/* Some firmwares need a pause here or they will silently fail
906	 * to set up the interface properly.  This value was decided
907	 * empirically on a Sierra Wireless MC7455 running 02.08.02.00
908	 * firmware.
909	 */
910	usleep_range(10000, 20000);
911
912	/* configure data interface */
913	temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
914	if (temp) {
915		dev_dbg(&intf->dev, "set interface failed\n");
916		goto error2;
917	}
918
919	cdc_ncm_find_endpoints(dev, ctx->data);
920	cdc_ncm_find_endpoints(dev, ctx->control);
921	if (!dev->in || !dev->out || !dev->status) {
922		dev_dbg(&intf->dev, "failed to collect endpoints\n");
923		goto error2;
924	}
925
926	usb_set_intfdata(ctx->data, dev);
927	usb_set_intfdata(ctx->control, dev);
928
929	if (ctx->ether_desc) {
930		temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
931		if (temp) {
932			dev_dbg(&intf->dev, "failed to get mac address\n");
933			goto error2;
934		}
935		dev_info(&intf->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
936	}
937
938	/* finish setting up the device specific data */
939	cdc_ncm_setup(dev);
940
941	/* Allocate the delayed NDP if needed. */
942	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
943		if (ctx->is_ndp16) {
944			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
945			if (!ctx->delayed_ndp16)
946				goto error2;
947		} else {
948			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
949			if (!ctx->delayed_ndp32)
950				goto error2;
951		}
952		dev_info(&intf->dev, "NDP will be placed at end of frame for this device.");
953	}
954
955	/* override ethtool_ops */
956	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
957
958	/* add our sysfs attrs */
959	dev->net->sysfs_groups[0] = &cdc_ncm_sysfs_attr_group;
960
961	/* must handle MTU changes */
962	dev->net->netdev_ops = &cdc_ncm_netdev_ops;
963	dev->net->max_mtu = cdc_ncm_max_dgram_size(dev) - cdc_ncm_eth_hlen(dev);
964
965	return 0;
966
967error2:
968	usb_set_intfdata(ctx->control, NULL);
969	usb_set_intfdata(ctx->data, NULL);
970	if (ctx->data != ctx->control)
971		usb_driver_release_interface(driver, ctx->data);
972error:
973	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
974	dev->data[0] = 0;
975	dev_info(&intf->dev, "bind() failure\n");
976	return -ENODEV;
977}
978EXPORT_SYMBOL_GPL(cdc_ncm_bind_common);
979
980void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
981{
982	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
983	struct usb_driver *driver = driver_of(intf);
984
985	if (ctx == NULL)
986		return;		/* no setup */
987
988	atomic_set(&ctx->stop, 1);
989
990	hrtimer_cancel(&ctx->tx_timer);
991
992	tasklet_kill(&ctx->bh);
993
994	/* handle devices with combined control and data interface */
995	if (ctx->control == ctx->data)
996		ctx->data = NULL;
997
998	/* disconnect master --> disconnect slave */
999	if (intf == ctx->control && ctx->data) {
1000		usb_set_intfdata(ctx->data, NULL);
1001		usb_driver_release_interface(driver, ctx->data);
1002		ctx->data = NULL;
1003
1004	} else if (intf == ctx->data && ctx->control) {
1005		usb_set_intfdata(ctx->control, NULL);
1006		usb_driver_release_interface(driver, ctx->control);
1007		ctx->control = NULL;
1008	}
1009
1010	usb_set_intfdata(intf, NULL);
1011	cdc_ncm_free(ctx);
1012}
1013EXPORT_SYMBOL_GPL(cdc_ncm_unbind);
1014
1015/* Return the number of the MBIM control interface altsetting iff it
1016 * is preferred and available,
1017 */
1018u8 cdc_ncm_select_altsetting(struct usb_interface *intf)
1019{
1020	struct usb_host_interface *alt;
1021
1022	/* The MBIM spec defines a NCM compatible default altsetting,
1023	 * which we may have matched:
1024	 *
1025	 *  "Functions that implement both NCM 1.0 and MBIM (an
1026	 *   “NCM/MBIM function”) according to this recommendation
1027	 *   shall provide two alternate settings for the
1028	 *   Communication Interface.  Alternate setting 0, and the
1029	 *   associated class and endpoint descriptors, shall be
1030	 *   constructed according to the rules given for the
1031	 *   Communication Interface in section 5 of [USBNCM10].
1032	 *   Alternate setting 1, and the associated class and
1033	 *   endpoint descriptors, shall be constructed according to
1034	 *   the rules given in section 6 (USB Device Model) of this
1035	 *   specification."
1036	 */
1037	if (intf->num_altsetting < 2)
1038		return intf->cur_altsetting->desc.bAlternateSetting;
1039
1040	if (prefer_mbim) {
1041		alt = usb_altnum_to_altsetting(intf, CDC_NCM_COMM_ALTSETTING_MBIM);
1042		if (alt && cdc_ncm_comm_intf_is_mbim(alt))
1043			return CDC_NCM_COMM_ALTSETTING_MBIM;
1044	}
1045	return CDC_NCM_COMM_ALTSETTING_NCM;
1046}
1047EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting);
1048
1049static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
1050{
1051	/* MBIM backwards compatible function? */
1052	if (cdc_ncm_select_altsetting(intf) != CDC_NCM_COMM_ALTSETTING_NCM)
1053		return -ENODEV;
1054
1055	/* The NCM data altsetting is fixed, so we hard-coded it.
1056	 * Additionally, generic NCM devices are assumed to accept arbitrarily
1057	 * placed NDP.
1058	 */
1059	return cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM, 0);
1060}
1061
1062static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max)
1063{
1064	size_t align = ALIGN(skb->len, modulus) - skb->len + remainder;
1065
1066	if (skb->len + align > max)
1067		align = max - skb->len;
1068	if (align && skb_tailroom(skb) >= align)
1069		skb_put_zero(skb, align);
1070}
1071
1072/* return a pointer to a valid struct usb_cdc_ncm_ndp16 of type sign, possibly
1073 * allocating a new one within skb
1074 */
1075static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1076{
1077	struct usb_cdc_ncm_ndp16 *ndp16 = NULL;
1078	struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
1079	size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
1080
1081	/* If NDP should be moved to the end of the NCM package, we can't follow the
1082	* NTH16 header as we would normally do. NDP isn't written to the SKB yet, and
1083	* the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1084	*/
1085	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1086		if (ctx->delayed_ndp16->dwSignature == sign)
1087			return ctx->delayed_ndp16;
1088
1089		/* We can only push a single NDP to the end. Return
1090		 * NULL to send what we've already got and queue this
1091		 * skb for later.
1092		 */
1093		else if (ctx->delayed_ndp16->dwSignature)
1094			return NULL;
1095	}
1096
1097	/* follow the chain of NDPs, looking for a match */
1098	while (ndpoffset) {
1099		ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
1100		if  (ndp16->dwSignature == sign)
1101			return ndp16;
1102		ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1103	}
1104
1105	/* align new NDP */
1106	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1107		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1108
1109	/* verify that there is room for the NDP and the datagram (reserve) */
1110	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1111		return NULL;
1112
1113	/* link to it */
1114	if (ndp16)
1115		ndp16->wNextNdpIndex = cpu_to_le16(skb->len);
1116	else
1117		nth16->wNdpIndex = cpu_to_le16(skb->len);
1118
1119	/* push a new empty NDP */
1120	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1121		ndp16 = skb_put_zero(skb, ctx->max_ndp_size);
1122	else
1123		ndp16 = ctx->delayed_ndp16;
1124
1125	ndp16->dwSignature = sign;
1126	ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
1127	return ndp16;
1128}
1129
1130static struct usb_cdc_ncm_ndp32 *cdc_ncm_ndp32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1131{
1132	struct usb_cdc_ncm_ndp32 *ndp32 = NULL;
1133	struct usb_cdc_ncm_nth32 *nth32 = (void *)skb->data;
1134	size_t ndpoffset = le32_to_cpu(nth32->dwNdpIndex);
1135
1136	/* If NDP should be moved to the end of the NCM package, we can't follow the
1137	 * NTH32 header as we would normally do. NDP isn't written to the SKB yet, and
1138	 * the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1139	 */
1140	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1141		if (ctx->delayed_ndp32->dwSignature == sign)
1142			return ctx->delayed_ndp32;
1143
1144		/* We can only push a single NDP to the end. Return
1145		 * NULL to send what we've already got and queue this
1146		 * skb for later.
1147		 */
1148		else if (ctx->delayed_ndp32->dwSignature)
1149			return NULL;
1150	}
1151
1152	/* follow the chain of NDPs, looking for a match */
1153	while (ndpoffset) {
1154		ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb->data + ndpoffset);
1155		if  (ndp32->dwSignature == sign)
1156			return ndp32;
1157		ndpoffset = le32_to_cpu(ndp32->dwNextNdpIndex);
1158	}
1159
1160	/* align new NDP */
1161	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1162		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1163
1164	/* verify that there is room for the NDP and the datagram (reserve) */
1165	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1166		return NULL;
1167
1168	/* link to it */
1169	if (ndp32)
1170		ndp32->dwNextNdpIndex = cpu_to_le32(skb->len);
1171	else
1172		nth32->dwNdpIndex = cpu_to_le32(skb->len);
1173
1174	/* push a new empty NDP */
1175	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1176		ndp32 = skb_put_zero(skb, ctx->max_ndp_size);
1177	else
1178		ndp32 = ctx->delayed_ndp32;
1179
1180	ndp32->dwSignature = sign;
1181	ndp32->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp32) + sizeof(struct usb_cdc_ncm_dpe32));
1182	return ndp32;
1183}
1184
1185struct sk_buff *
1186cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
1187{
1188	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1189	union {
1190		struct usb_cdc_ncm_nth16 *nth16;
1191		struct usb_cdc_ncm_nth32 *nth32;
1192	} nth;
1193	union {
1194		struct usb_cdc_ncm_ndp16 *ndp16;
1195		struct usb_cdc_ncm_ndp32 *ndp32;
1196	} ndp;
1197	struct sk_buff *skb_out;
1198	u16 n = 0, index, ndplen;
1199	u8 ready2send = 0;
1200	u32 delayed_ndp_size;
1201	size_t padding_count;
1202
1203	/* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated
1204	 * accordingly. Otherwise, we should check here.
1205	 */
1206	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
1207		delayed_ndp_size = ctx->max_ndp_size +
1208			max_t(u32,
1209			      ctx->tx_ndp_modulus,
1210			      ctx->tx_modulus + ctx->tx_remainder) - 1;
1211	else
1212		delayed_ndp_size = 0;
1213
1214	/* if there is a remaining skb, it gets priority */
1215	if (skb != NULL) {
1216		swap(skb, ctx->tx_rem_skb);
1217		swap(sign, ctx->tx_rem_sign);
1218	} else {
1219		ready2send = 1;
1220	}
1221
1222	/* check if we are resuming an OUT skb */
1223	skb_out = ctx->tx_curr_skb;
1224
1225	/* allocate a new OUT skb */
1226	if (!skb_out) {
1227		if (ctx->tx_low_mem_val == 0) {
1228			ctx->tx_curr_size = ctx->tx_max;
1229			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1230			/* If the memory allocation fails we will wait longer
1231			 * each time before attempting another full size
1232			 * allocation again to not overload the system
1233			 * further.
1234			 */
1235			if (skb_out == NULL) {
1236				/* If even the smallest allocation fails, abort. */
1237				if (ctx->tx_curr_size == USB_CDC_NCM_NTB_MIN_OUT_SIZE)
1238					goto alloc_failed;
1239				ctx->tx_low_mem_max_cnt = min(ctx->tx_low_mem_max_cnt + 1,
1240							      (unsigned)CDC_NCM_LOW_MEM_MAX_CNT);
1241				ctx->tx_low_mem_val = ctx->tx_low_mem_max_cnt;
1242			}
1243		}
1244		if (skb_out == NULL) {
1245			/* See if a very small allocation is possible.
1246			 * We will send this packet immediately and hope
1247			 * that there is more memory available later.
1248			 */
1249			if (skb)
1250				ctx->tx_curr_size = max(skb->len,
1251					(u32)USB_CDC_NCM_NTB_MIN_OUT_SIZE);
1252			else
1253				ctx->tx_curr_size = USB_CDC_NCM_NTB_MIN_OUT_SIZE;
1254			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1255
1256			/* No allocation possible so we will abort */
1257			if (!skb_out)
1258				goto alloc_failed;
1259			ctx->tx_low_mem_val--;
1260		}
1261		if (ctx->is_ndp16) {
1262			/* fill out the initial 16-bit NTB header */
1263			nth.nth16 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth16));
1264			nth.nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
1265			nth.nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
1266			nth.nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
1267		} else {
1268			/* fill out the initial 32-bit NTB header */
1269			nth.nth32 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth32));
1270			nth.nth32->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH32_SIGN);
1271			nth.nth32->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth32));
1272			nth.nth32->wSequence = cpu_to_le16(ctx->tx_seq++);
1273		}
1274
1275		/* count total number of frames in this NTB */
1276		ctx->tx_curr_frame_num = 0;
1277
1278		/* recent payload counter for this skb_out */
1279		ctx->tx_curr_frame_payload = 0;
1280	}
1281
1282	for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
1283		/* send any remaining skb first */
1284		if (skb == NULL) {
1285			skb = ctx->tx_rem_skb;
1286			sign = ctx->tx_rem_sign;
1287			ctx->tx_rem_skb = NULL;
1288
1289			/* check for end of skb */
1290			if (skb == NULL)
1291				break;
1292		}
1293
1294		/* get the appropriate NDP for this skb */
1295		if (ctx->is_ndp16)
1296			ndp.ndp16 = cdc_ncm_ndp16(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1297		else
1298			ndp.ndp32 = cdc_ncm_ndp32(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1299
1300		/* align beginning of next frame */
1301		cdc_ncm_align_tail(skb_out,  ctx->tx_modulus, ctx->tx_remainder, ctx->tx_curr_size);
1302
1303		/* check if we had enough room left for both NDP and frame */
1304		if ((ctx->is_ndp16 && !ndp.ndp16) || (!ctx->is_ndp16 && !ndp.ndp32) ||
1305		    skb_out->len + skb->len + delayed_ndp_size > ctx->tx_curr_size) {
1306			if (n == 0) {
1307				/* won't fit, MTU problem? */
1308				dev_kfree_skb_any(skb);
1309				skb = NULL;
1310				dev->net->stats.tx_dropped++;
1311			} else {
1312				/* no room for skb - store for later */
1313				if (ctx->tx_rem_skb != NULL) {
1314					dev_kfree_skb_any(ctx->tx_rem_skb);
1315					dev->net->stats.tx_dropped++;
1316				}
1317				ctx->tx_rem_skb = skb;
1318				ctx->tx_rem_sign = sign;
1319				skb = NULL;
1320				ready2send = 1;
1321				ctx->tx_reason_ntb_full++;	/* count reason for transmitting */
1322			}
1323			break;
1324		}
1325
1326		/* calculate frame number withing this NDP */
1327		if (ctx->is_ndp16) {
1328			ndplen = le16_to_cpu(ndp.ndp16->wLength);
1329			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
1330
1331			/* OK, add this skb */
1332			ndp.ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
1333			ndp.ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
1334			ndp.ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
1335		} else {
1336			ndplen = le16_to_cpu(ndp.ndp32->wLength);
1337			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp32)) / sizeof(struct usb_cdc_ncm_dpe32) - 1;
1338
1339			ndp.ndp32->dpe32[index].dwDatagramLength = cpu_to_le32(skb->len);
1340			ndp.ndp32->dpe32[index].dwDatagramIndex = cpu_to_le32(skb_out->len);
1341			ndp.ndp32->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe32));
1342		}
1343		skb_put_data(skb_out, skb->data, skb->len);
1344		ctx->tx_curr_frame_payload += skb->len;	/* count real tx payload data */
1345		dev_kfree_skb_any(skb);
1346		skb = NULL;
1347
1348		/* send now if this NDP is full */
1349		if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
1350			ready2send = 1;
1351			ctx->tx_reason_ndp_full++;	/* count reason for transmitting */
1352			break;
1353		}
1354	}
1355
1356	/* free up any dangling skb */
1357	if (skb != NULL) {
1358		dev_kfree_skb_any(skb);
1359		skb = NULL;
1360		dev->net->stats.tx_dropped++;
1361	}
1362
1363	ctx->tx_curr_frame_num = n;
1364
1365	if (n == 0) {
1366		/* wait for more frames */
1367		/* push variables */
1368		ctx->tx_curr_skb = skb_out;
1369		goto exit_no_skb;
1370
1371	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0) && (ctx->timer_interval > 0)) {
1372		/* wait for more frames */
1373		/* push variables */
1374		ctx->tx_curr_skb = skb_out;
1375		/* set the pending count */
1376		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
1377			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
1378		goto exit_no_skb;
1379
1380	} else {
1381		if (n == ctx->tx_max_datagrams)
1382			ctx->tx_reason_max_datagram++;	/* count reason for transmitting */
1383		/* frame goes out */
1384		/* variables will be reset at next call */
1385	}
1386
1387	/* If requested, put NDP at end of frame. */
1388	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1389		if (ctx->is_ndp16) {
1390			nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1391			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1392			nth.nth16->wNdpIndex = cpu_to_le16(skb_out->len);
1393			skb_put_data(skb_out, ctx->delayed_ndp16, ctx->max_ndp_size);
1394
1395			/* Zero out delayed NDP - signature checking will naturally fail. */
1396			ndp.ndp16 = memset(ctx->delayed_ndp16, 0, ctx->max_ndp_size);
1397		} else {
1398			nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1399			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1400			nth.nth32->dwNdpIndex = cpu_to_le32(skb_out->len);
1401			skb_put_data(skb_out, ctx->delayed_ndp32, ctx->max_ndp_size);
1402
1403			ndp.ndp32 = memset(ctx->delayed_ndp32, 0, ctx->max_ndp_size);
1404		}
1405	}
1406
1407	/* If collected data size is less or equal ctx->min_tx_pkt
1408	 * bytes, we send buffers as it is. If we get more data, it
1409	 * would be more efficient for USB HS mobile device with DMA
1410	 * engine to receive a full size NTB, than canceling DMA
1411	 * transfer and receiving a short packet.
1412	 *
1413	 * This optimization support is pointless if we end up sending
1414	 * a ZLP after full sized NTBs.
1415	 */
1416	if (!(dev->driver_info->flags & FLAG_SEND_ZLP) &&
1417	    skb_out->len > ctx->min_tx_pkt) {
1418		padding_count = ctx->tx_curr_size - skb_out->len;
1419		if (!WARN_ON(padding_count > ctx->tx_curr_size))
1420			skb_put_zero(skb_out, padding_count);
1421	} else if (skb_out->len < ctx->tx_curr_size &&
1422		   (skb_out->len % dev->maxpacket) == 0) {
1423		skb_put_u8(skb_out, 0);	/* force short packet */
1424	}
1425
1426	/* set final frame length */
1427	if (ctx->is_ndp16) {
1428		nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1429		nth.nth16->wBlockLength = cpu_to_le16(skb_out->len);
1430	} else {
1431		nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1432		nth.nth32->dwBlockLength = cpu_to_le32(skb_out->len);
1433	}
1434
1435	/* return skb */
1436	ctx->tx_curr_skb = NULL;
1437
1438	/* keep private stats: framing overhead and number of NTBs */
1439	ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
1440	ctx->tx_ntbs++;
1441
1442	/* usbnet will count all the framing overhead by default.
1443	 * Adjust the stats so that the tx_bytes counter show real
1444	 * payload data instead.
1445	 */
1446	usbnet_set_skb_tx_stats(skb_out, n,
1447				(long)ctx->tx_curr_frame_payload - skb_out->len);
1448
1449	return skb_out;
1450
1451alloc_failed:
1452	if (skb) {
1453		dev_kfree_skb_any(skb);
1454		dev->net->stats.tx_dropped++;
1455	}
1456exit_no_skb:
1457	/* Start timer, if there is a remaining non-empty skb */
1458	if (ctx->tx_curr_skb != NULL && n > 0)
1459		cdc_ncm_tx_timeout_start(ctx);
1460	return NULL;
1461}
1462EXPORT_SYMBOL_GPL(cdc_ncm_fill_tx_frame);
1463
1464static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
1465{
1466	/* start timer, if not already started */
1467	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
1468		hrtimer_start(&ctx->tx_timer,
1469				ctx->timer_interval,
1470				HRTIMER_MODE_REL);
1471}
1472
1473static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
1474{
1475	struct cdc_ncm_ctx *ctx =
1476			container_of(timer, struct cdc_ncm_ctx, tx_timer);
1477
1478	if (!atomic_read(&ctx->stop))
1479		tasklet_schedule(&ctx->bh);
1480	return HRTIMER_NORESTART;
1481}
1482
1483static void cdc_ncm_txpath_bh(unsigned long param)
1484{
1485	struct usbnet *dev = (struct usbnet *)param;
1486	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1487
1488	spin_lock_bh(&ctx->mtx);
1489	if (ctx->tx_timer_pending != 0) {
1490		ctx->tx_timer_pending--;
1491		cdc_ncm_tx_timeout_start(ctx);
1492		spin_unlock_bh(&ctx->mtx);
1493	} else if (dev->net != NULL) {
1494		ctx->tx_reason_timeout++;	/* count reason for transmitting */
1495		spin_unlock_bh(&ctx->mtx);
1496		netif_tx_lock_bh(dev->net);
1497		usbnet_start_xmit(NULL, dev->net);
1498		netif_tx_unlock_bh(dev->net);
1499	} else {
1500		spin_unlock_bh(&ctx->mtx);
1501	}
1502}
1503
1504struct sk_buff *
1505cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
1506{
1507	struct sk_buff *skb_out;
1508	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1509
1510	/*
1511	 * The Ethernet API we are using does not support transmitting
1512	 * multiple Ethernet frames in a single call. This driver will
1513	 * accumulate multiple Ethernet frames and send out a larger
1514	 * USB frame when the USB buffer is full or when a single jiffies
1515	 * timeout happens.
1516	 */
1517	if (ctx == NULL)
1518		goto error;
1519
1520	spin_lock_bh(&ctx->mtx);
1521
1522	if (ctx->is_ndp16)
1523		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN));
1524	else
1525		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN));
1526
1527	spin_unlock_bh(&ctx->mtx);
1528	return skb_out;
1529
1530error:
1531	if (skb != NULL)
1532		dev_kfree_skb_any(skb);
1533
1534	return NULL;
1535}
1536EXPORT_SYMBOL_GPL(cdc_ncm_tx_fixup);
1537
1538/* verify NTB header and return offset of first NDP, or negative error */
1539int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1540{
1541	struct usbnet *dev = netdev_priv(skb_in->dev);
1542	struct usb_cdc_ncm_nth16 *nth16;
1543	int len;
1544	int ret = -EINVAL;
1545
1546	if (ctx == NULL)
1547		goto error;
1548
1549	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
1550					sizeof(struct usb_cdc_ncm_ndp16))) {
1551		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1552		goto error;
1553	}
1554
1555	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
1556
1557	if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
1558		netif_dbg(dev, rx_err, dev->net,
1559			  "invalid NTH16 signature <%#010x>\n",
1560			  le32_to_cpu(nth16->dwSignature));
1561		goto error;
1562	}
1563
1564	len = le16_to_cpu(nth16->wBlockLength);
1565	if (len > ctx->rx_max) {
1566		netif_dbg(dev, rx_err, dev->net,
1567			  "unsupported NTB block length %u/%u\n", len,
1568			  ctx->rx_max);
1569		goto error;
1570	}
1571
1572	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
1573	    (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
1574	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
1575		netif_dbg(dev, rx_err, dev->net,
1576			  "sequence number glitch prev=%d curr=%d\n",
1577			  ctx->rx_seq, le16_to_cpu(nth16->wSequence));
1578	}
1579	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
1580
1581	ret = le16_to_cpu(nth16->wNdpIndex);
1582error:
1583	return ret;
1584}
1585EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth16);
1586
1587int cdc_ncm_rx_verify_nth32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1588{
1589	struct usbnet *dev = netdev_priv(skb_in->dev);
1590	struct usb_cdc_ncm_nth32 *nth32;
1591	int len;
1592	int ret = -EINVAL;
1593
1594	if (ctx == NULL)
1595		goto error;
1596
1597	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth32) +
1598					sizeof(struct usb_cdc_ncm_ndp32))) {
1599		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1600		goto error;
1601	}
1602
1603	nth32 = (struct usb_cdc_ncm_nth32 *)skb_in->data;
1604
1605	if (nth32->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH32_SIGN)) {
1606		netif_dbg(dev, rx_err, dev->net,
1607			  "invalid NTH32 signature <%#010x>\n",
1608			  le32_to_cpu(nth32->dwSignature));
1609		goto error;
1610	}
1611
1612	len = le32_to_cpu(nth32->dwBlockLength);
1613	if (len > ctx->rx_max) {
1614		netif_dbg(dev, rx_err, dev->net,
1615			  "unsupported NTB block length %u/%u\n", len,
1616			  ctx->rx_max);
1617		goto error;
1618	}
1619
1620	if ((ctx->rx_seq + 1) != le16_to_cpu(nth32->wSequence) &&
1621	    (ctx->rx_seq || le16_to_cpu(nth32->wSequence)) &&
1622	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth32->wSequence))) {
1623		netif_dbg(dev, rx_err, dev->net,
1624			  "sequence number glitch prev=%d curr=%d\n",
1625			  ctx->rx_seq, le16_to_cpu(nth32->wSequence));
1626	}
1627	ctx->rx_seq = le16_to_cpu(nth32->wSequence);
1628
1629	ret = le32_to_cpu(nth32->dwNdpIndex);
1630error:
1631	return ret;
1632}
1633EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth32);
1634
1635/* verify NDP header and return number of datagrams, or negative error */
1636int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
1637{
1638	struct usbnet *dev = netdev_priv(skb_in->dev);
1639	struct usb_cdc_ncm_ndp16 *ndp16;
1640	int ret = -EINVAL;
1641
1642	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
1643		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1644			  ndpoffset);
1645		goto error;
1646	}
1647	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1648
1649	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1650		netif_dbg(dev, rx_err, dev->net, "invalid DPT16 length <%u>\n",
1651			  le16_to_cpu(ndp16->wLength));
1652		goto error;
1653	}
1654
1655	ret = ((le16_to_cpu(ndp16->wLength) -
1656					sizeof(struct usb_cdc_ncm_ndp16)) /
1657					sizeof(struct usb_cdc_ncm_dpe16));
1658	ret--; /* we process NDP entries except for the last one */
1659
1660	if ((sizeof(struct usb_cdc_ncm_ndp16) +
1661	     ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) {
1662		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1663		ret = -EINVAL;
1664	}
1665
1666error:
1667	return ret;
1668}
1669EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp16);
1670
1671/* verify NDP header and return number of datagrams, or negative error */
1672int cdc_ncm_rx_verify_ndp32(struct sk_buff *skb_in, int ndpoffset)
1673{
1674	struct usbnet *dev = netdev_priv(skb_in->dev);
1675	struct usb_cdc_ncm_ndp32 *ndp32;
1676	int ret = -EINVAL;
1677
1678	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp32)) > skb_in->len) {
1679		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1680			  ndpoffset);
1681		goto error;
1682	}
1683	ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1684
1685	if (le16_to_cpu(ndp32->wLength) < USB_CDC_NCM_NDP32_LENGTH_MIN) {
1686		netif_dbg(dev, rx_err, dev->net, "invalid DPT32 length <%u>\n",
1687			  le16_to_cpu(ndp32->wLength));
1688		goto error;
1689	}
1690
1691	ret = ((le16_to_cpu(ndp32->wLength) -
1692					sizeof(struct usb_cdc_ncm_ndp32)) /
1693					sizeof(struct usb_cdc_ncm_dpe32));
1694	ret--; /* we process NDP entries except for the last one */
1695
1696	if ((sizeof(struct usb_cdc_ncm_ndp32) +
1697	     ret * (sizeof(struct usb_cdc_ncm_dpe32))) > skb_in->len) {
1698		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1699		ret = -EINVAL;
1700	}
1701
1702error:
1703	return ret;
1704}
1705EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp32);
1706
1707int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
1708{
1709	struct sk_buff *skb;
1710	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1711	unsigned int len;
1712	int nframes;
1713	int x;
1714	unsigned int offset;
1715	union {
1716		struct usb_cdc_ncm_ndp16 *ndp16;
1717		struct usb_cdc_ncm_ndp32 *ndp32;
1718	} ndp;
1719	union {
1720		struct usb_cdc_ncm_dpe16 *dpe16;
1721		struct usb_cdc_ncm_dpe32 *dpe32;
1722	} dpe;
1723
1724	int ndpoffset;
1725	int loopcount = 50; /* arbitrary max preventing infinite loop */
1726	u32 payload = 0;
1727
1728	if (ctx->is_ndp16)
1729		ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
1730	else
1731		ndpoffset = cdc_ncm_rx_verify_nth32(ctx, skb_in);
1732
1733	if (ndpoffset < 0)
1734		goto error;
1735
1736next_ndp:
1737	if (ctx->is_ndp16) {
1738		nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
1739		if (nframes < 0)
1740			goto error;
1741
1742		ndp.ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1743
1744		if (ndp.ndp16->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) {
1745			netif_dbg(dev, rx_err, dev->net,
1746				  "invalid DPT16 signature <%#010x>\n",
1747				  le32_to_cpu(ndp.ndp16->dwSignature));
1748			goto err_ndp;
1749		}
1750		dpe.dpe16 = ndp.ndp16->dpe16;
1751	} else {
1752		nframes = cdc_ncm_rx_verify_ndp32(skb_in, ndpoffset);
1753		if (nframes < 0)
1754			goto error;
1755
1756		ndp.ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1757
1758		if (ndp.ndp32->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN)) {
1759			netif_dbg(dev, rx_err, dev->net,
1760				  "invalid DPT32 signature <%#010x>\n",
1761				  le32_to_cpu(ndp.ndp32->dwSignature));
1762			goto err_ndp;
1763		}
1764		dpe.dpe32 = ndp.ndp32->dpe32;
1765	}
1766
1767	for (x = 0; x < nframes; x++) {
1768		if (ctx->is_ndp16) {
1769			offset = le16_to_cpu(dpe.dpe16->wDatagramIndex);
1770			len = le16_to_cpu(dpe.dpe16->wDatagramLength);
1771		} else {
1772			offset = le32_to_cpu(dpe.dpe32->dwDatagramIndex);
1773			len = le32_to_cpu(dpe.dpe32->dwDatagramLength);
1774		}
1775
1776		/*
1777		 * CDC NCM ch. 3.7
1778		 * All entries after first NULL entry are to be ignored
1779		 */
1780		if ((offset == 0) || (len == 0)) {
1781			if (!x)
1782				goto err_ndp; /* empty NTB */
1783			break;
1784		}
1785
1786		/* sanity checking - watch out for integer wrap*/
1787		if ((offset > skb_in->len) || (len > skb_in->len - offset) ||
1788				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1789			netif_dbg(dev, rx_err, dev->net,
1790				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
1791				  x, offset, len, skb_in);
1792			if (!x)
1793				goto err_ndp;
1794			break;
1795
1796		} else {
1797			/* create a fresh copy to reduce truesize */
1798			skb = netdev_alloc_skb_ip_align(dev->net,  len);
1799			if (!skb)
1800				goto error;
1801			skb_put_data(skb, skb_in->data + offset, len);
1802			usbnet_skb_return(dev, skb);
1803			payload += len;	/* count payload bytes in this NTB */
1804		}
1805
1806		if (ctx->is_ndp16)
1807			dpe.dpe16++;
1808		else
1809			dpe.dpe32++;
1810	}
1811err_ndp:
1812	/* are there more NDPs to process? */
1813	if (ctx->is_ndp16)
1814		ndpoffset = le16_to_cpu(ndp.ndp16->wNextNdpIndex);
1815	else
1816		ndpoffset = le32_to_cpu(ndp.ndp32->dwNextNdpIndex);
1817
1818	if (ndpoffset && loopcount--)
1819		goto next_ndp;
1820
1821	/* update stats */
1822	ctx->rx_overhead += skb_in->len - payload;
1823	ctx->rx_ntbs++;
1824
1825	return 1;
1826error:
1827	return 0;
1828}
1829EXPORT_SYMBOL_GPL(cdc_ncm_rx_fixup);
1830
1831static void
1832cdc_ncm_speed_change(struct usbnet *dev,
1833		     struct usb_cdc_speed_change *data)
1834{
1835	uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
1836	uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
1837
1838	/* if the speed hasn't changed, don't report it.
1839	 * RTL8156 shipped before 2021 sends notification about every 32ms.
1840	 */
1841	if (dev->rx_speed == rx_speed && dev->tx_speed == tx_speed)
1842		return;
1843
1844	dev->rx_speed = rx_speed;
1845	dev->tx_speed = tx_speed;
1846
1847	/*
1848	 * Currently the USB-NET API does not support reporting the actual
1849	 * device speed. Do print it instead.
1850	 */
1851	if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
1852		netif_info(dev, link, dev->net,
1853			   "%u mbit/s downlink %u mbit/s uplink\n",
1854			   (unsigned int)(rx_speed / 1000000U),
1855			   (unsigned int)(tx_speed / 1000000U));
1856	} else {
1857		netif_info(dev, link, dev->net,
1858			   "%u kbit/s downlink %u kbit/s uplink\n",
1859			   (unsigned int)(rx_speed / 1000U),
1860			   (unsigned int)(tx_speed / 1000U));
1861	}
1862}
1863
1864static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1865{
1866	struct usb_cdc_notification *event;
1867
1868	if (urb->actual_length < sizeof(*event))
1869		return;
1870
1871	/* test for split data in 8-byte chunks */
1872	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1873		cdc_ncm_speed_change(dev,
1874		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1875		return;
1876	}
1877
1878	event = urb->transfer_buffer;
1879
1880	switch (event->bNotificationType) {
1881	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1882		/*
1883		 * According to the CDC NCM specification ch.7.1
1884		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1885		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1886		 */
1887		if (netif_carrier_ok(dev->net) != !!event->wValue)
1888			usbnet_link_change(dev, !!event->wValue, 0);
1889		break;
1890
1891	case USB_CDC_NOTIFY_SPEED_CHANGE:
1892		if (urb->actual_length < (sizeof(*event) +
1893					sizeof(struct usb_cdc_speed_change)))
1894			set_bit(EVENT_STS_SPLIT, &dev->flags);
1895		else
1896			cdc_ncm_speed_change(dev,
1897					     (struct usb_cdc_speed_change *)&event[1]);
1898		break;
1899
1900	default:
1901		dev_dbg(&dev->udev->dev,
1902			"NCM: unexpected notification 0x%02x!\n",
1903			event->bNotificationType);
1904		break;
1905	}
1906}
1907
1908static const struct driver_info cdc_ncm_info = {
1909	.description = "CDC NCM",
1910	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1911			| FLAG_LINK_INTR | FLAG_ETHER,
1912	.bind = cdc_ncm_bind,
1913	.unbind = cdc_ncm_unbind,
1914	.manage_power = usbnet_manage_power,
1915	.status = cdc_ncm_status,
1916	.rx_fixup = cdc_ncm_rx_fixup,
1917	.tx_fixup = cdc_ncm_tx_fixup,
1918	.set_rx_mode = usbnet_cdc_update_filter,
1919};
1920
1921/* Same as cdc_ncm_info, but with FLAG_WWAN */
1922static const struct driver_info wwan_info = {
1923	.description = "Mobile Broadband Network Device",
1924	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1925			| FLAG_LINK_INTR | FLAG_WWAN,
1926	.bind = cdc_ncm_bind,
1927	.unbind = cdc_ncm_unbind,
1928	.manage_power = usbnet_manage_power,
1929	.status = cdc_ncm_status,
1930	.rx_fixup = cdc_ncm_rx_fixup,
1931	.tx_fixup = cdc_ncm_tx_fixup,
1932	.set_rx_mode = usbnet_cdc_update_filter,
1933};
1934
1935/* Same as wwan_info, but with FLAG_NOARP  */
1936static const struct driver_info wwan_noarp_info = {
1937	.description = "Mobile Broadband Network Device (NO ARP)",
1938	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1939			| FLAG_LINK_INTR | FLAG_WWAN | FLAG_NOARP,
1940	.bind = cdc_ncm_bind,
1941	.unbind = cdc_ncm_unbind,
1942	.manage_power = usbnet_manage_power,
1943	.status = cdc_ncm_status,
1944	.rx_fixup = cdc_ncm_rx_fixup,
1945	.tx_fixup = cdc_ncm_tx_fixup,
1946	.set_rx_mode = usbnet_cdc_update_filter,
1947};
1948
1949static const struct usb_device_id cdc_devs[] = {
1950	/* Ericsson MBM devices like F5521gw */
1951	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1952		| USB_DEVICE_ID_MATCH_VENDOR,
1953	  .idVendor = 0x0bdb,
1954	  .bInterfaceClass = USB_CLASS_COMM,
1955	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1956	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1957	  .driver_info = (unsigned long) &wwan_info,
1958	},
1959
1960	/* Telit LE910 V2 */
1961	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x0036,
1962		USB_CLASS_COMM,
1963		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1964	  .driver_info = (unsigned long)&wwan_noarp_info,
1965	},
1966
1967	/* DW5812 LTE Verizon Mobile Broadband Card
1968	 * Unlike DW5550 this device requires FLAG_NOARP
1969	 */
1970	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bb,
1971		USB_CLASS_COMM,
1972		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1973	  .driver_info = (unsigned long)&wwan_noarp_info,
1974	},
1975
1976	/* DW5813 LTE AT&T Mobile Broadband Card
1977	 * Unlike DW5550 this device requires FLAG_NOARP
1978	 */
1979	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bc,
1980		USB_CLASS_COMM,
1981		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1982	  .driver_info = (unsigned long)&wwan_noarp_info,
1983	},
1984
1985	/* Dell branded MBM devices like DW5550 */
1986	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1987		| USB_DEVICE_ID_MATCH_VENDOR,
1988	  .idVendor = 0x413c,
1989	  .bInterfaceClass = USB_CLASS_COMM,
1990	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1991	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1992	  .driver_info = (unsigned long) &wwan_info,
1993	},
1994
1995	/* Toshiba branded MBM devices */
1996	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1997		| USB_DEVICE_ID_MATCH_VENDOR,
1998	  .idVendor = 0x0930,
1999	  .bInterfaceClass = USB_CLASS_COMM,
2000	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
2001	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
2002	  .driver_info = (unsigned long) &wwan_info,
2003	},
2004
2005	/* tag Huawei devices as wwan */
2006	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1,
2007					USB_CLASS_COMM,
2008					USB_CDC_SUBCLASS_NCM,
2009					USB_CDC_PROTO_NONE),
2010	  .driver_info = (unsigned long)&wwan_info,
2011	},
2012
2013	/* Infineon(now Intel) HSPA Modem platform */
2014	{ USB_DEVICE_AND_INTERFACE_INFO(0x1519, 0x0443,
2015		USB_CLASS_COMM,
2016		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2017	  .driver_info = (unsigned long)&wwan_noarp_info,
2018	},
2019
2020	/* u-blox TOBY-L4 */
2021	{ USB_DEVICE_AND_INTERFACE_INFO(0x1546, 0x1010,
2022		USB_CLASS_COMM,
2023		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2024	  .driver_info = (unsigned long)&wwan_info,
2025	},
2026
2027	/* Generic CDC-NCM devices */
2028	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
2029		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2030		.driver_info = (unsigned long)&cdc_ncm_info,
2031	},
2032	{
2033	},
2034};
2035MODULE_DEVICE_TABLE(usb, cdc_devs);
2036
2037static struct usb_driver cdc_ncm_driver = {
2038	.name = "cdc_ncm",
2039	.id_table = cdc_devs,
2040	.probe = usbnet_probe,
2041	.disconnect = usbnet_disconnect,
2042	.suspend = usbnet_suspend,
2043	.resume = usbnet_resume,
2044	.reset_resume =	usbnet_resume,
2045	.supports_autosuspend = 1,
2046	.disable_hub_initiated_lpm = 1,
2047};
2048
2049module_usb_driver(cdc_ncm_driver);
2050
2051MODULE_AUTHOR("Hans Petter Selasky");
2052MODULE_DESCRIPTION("USB CDC NCM host driver");
2053MODULE_LICENSE("Dual BSD/GPL");
2054