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/kstrtox.h>
47#include <linux/workqueue.h>
48#include <linux/mii.h>
49#include <linux/crc32.h>
50#include <linux/usb.h>
51#include <linux/hrtimer.h>
52#include <linux/atomic.h>
53#include <linux/usb/usbnet.h>
54#include <linux/usb/cdc.h>
55#include <linux/usb/cdc_ncm.h>
56
57#if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM)
58static bool prefer_mbim = true;
59#else
60static bool prefer_mbim;
61#endif
62module_param(prefer_mbim, bool, 0644);
63MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
64
65static void cdc_ncm_txpath_bh(struct tasklet_struct *t);
66static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
67static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
68static struct usb_driver cdc_ncm_driver;
69
70struct cdc_ncm_stats {
71	char stat_string[ETH_GSTRING_LEN];
72	int sizeof_stat;
73	int stat_offset;
74};
75
76#define CDC_NCM_STAT(str, m) { \
77		.stat_string = str, \
78		.sizeof_stat = sizeof(((struct cdc_ncm_ctx *)0)->m), \
79		.stat_offset = offsetof(struct cdc_ncm_ctx, m) }
80#define CDC_NCM_SIMPLE_STAT(m)	CDC_NCM_STAT(__stringify(m), m)
81
82static const struct cdc_ncm_stats cdc_ncm_gstrings_stats[] = {
83	CDC_NCM_SIMPLE_STAT(tx_reason_ntb_full),
84	CDC_NCM_SIMPLE_STAT(tx_reason_ndp_full),
85	CDC_NCM_SIMPLE_STAT(tx_reason_timeout),
86	CDC_NCM_SIMPLE_STAT(tx_reason_max_datagram),
87	CDC_NCM_SIMPLE_STAT(tx_overhead),
88	CDC_NCM_SIMPLE_STAT(tx_ntbs),
89	CDC_NCM_SIMPLE_STAT(rx_overhead),
90	CDC_NCM_SIMPLE_STAT(rx_ntbs),
91};
92
93#define CDC_NCM_LOW_MEM_MAX_CNT 10
94
95static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset)
96{
97	switch (sset) {
98	case ETH_SS_STATS:
99		return ARRAY_SIZE(cdc_ncm_gstrings_stats);
100	default:
101		return -EOPNOTSUPP;
102	}
103}
104
105static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
106				    struct ethtool_stats __always_unused *stats,
107				    u64 *data)
108{
109	struct usbnet *dev = netdev_priv(netdev);
110	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
111	int i;
112	char *p = NULL;
113
114	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
115		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
116		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
117	}
118}
119
120static void cdc_ncm_get_strings(struct net_device __always_unused *netdev, u32 stringset, u8 *data)
121{
122	u8 *p = data;
123	int i;
124
125	switch (stringset) {
126	case ETH_SS_STATS:
127		for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
128			memcpy(p, cdc_ncm_gstrings_stats[i].stat_string, ETH_GSTRING_LEN);
129			p += ETH_GSTRING_LEN;
130		}
131	}
132}
133
134static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx);
135
136static const struct ethtool_ops cdc_ncm_ethtool_ops = {
137	.get_link		= usbnet_get_link,
138	.nway_reset		= usbnet_nway_reset,
139	.get_drvinfo		= usbnet_get_drvinfo,
140	.get_msglevel		= usbnet_get_msglevel,
141	.set_msglevel		= usbnet_set_msglevel,
142	.get_ts_info		= ethtool_op_get_ts_info,
143	.get_sset_count		= cdc_ncm_get_sset_count,
144	.get_strings		= cdc_ncm_get_strings,
145	.get_ethtool_stats	= cdc_ncm_get_ethtool_stats,
146	.get_link_ksettings	= usbnet_get_link_ksettings_internal,
147	.set_link_ksettings	= NULL,
148};
149
150static u32 cdc_ncm_check_rx_max(struct usbnet *dev, u32 new_rx)
151{
152	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
153	u32 val, max, min;
154
155	/* clamp new_rx to sane values */
156	min = USB_CDC_NCM_NTB_MIN_IN_SIZE;
157	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_RX, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
158
159	/* dwNtbInMaxSize spec violation? Use MIN size for both limits */
160	if (max < min) {
161		dev_warn(&dev->intf->dev, "dwNtbInMaxSize=%u is too small. Using %u\n",
162			 le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize), min);
163		max = min;
164	}
165
166	val = clamp_t(u32, new_rx, min, max);
167	if (val != new_rx)
168		dev_dbg(&dev->intf->dev, "rx_max must be in the [%u, %u] range\n", min, max);
169
170	return val;
171}
172
173static u32 cdc_ncm_check_tx_max(struct usbnet *dev, u32 new_tx)
174{
175	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
176	u32 val, max, min;
177
178	/* clamp new_tx to sane values */
179	if (ctx->is_ndp16)
180		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth16);
181	else
182		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth32);
183
184	if (le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) == 0)
185		max = CDC_NCM_NTB_MAX_SIZE_TX; /* dwNtbOutMaxSize not set */
186	else
187		max = clamp_t(u32, le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize),
188			      USB_CDC_NCM_NTB_MIN_OUT_SIZE,
189			      CDC_NCM_NTB_MAX_SIZE_TX);
190
191	/* some devices set dwNtbOutMaxSize too low for the above default */
192	min = min(min, max);
193
194	val = clamp_t(u32, new_tx, min, max);
195	if (val != new_tx)
196		dev_dbg(&dev->intf->dev, "tx_max must be in the [%u, %u] range\n", min, max);
197
198	return val;
199}
200
201static ssize_t min_tx_pkt_show(struct device *d,
202			       struct device_attribute *attr, char *buf)
203{
204	struct usbnet *dev = netdev_priv(to_net_dev(d));
205	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
206
207	return sprintf(buf, "%u\n", ctx->min_tx_pkt);
208}
209
210static ssize_t rx_max_show(struct device *d,
211			   struct device_attribute *attr, char *buf)
212{
213	struct usbnet *dev = netdev_priv(to_net_dev(d));
214	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
215
216	return sprintf(buf, "%u\n", ctx->rx_max);
217}
218
219static ssize_t tx_max_show(struct device *d,
220			   struct device_attribute *attr, char *buf)
221{
222	struct usbnet *dev = netdev_priv(to_net_dev(d));
223	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
224
225	return sprintf(buf, "%u\n", ctx->tx_max);
226}
227
228static ssize_t tx_timer_usecs_show(struct device *d,
229				   struct device_attribute *attr, char *buf)
230{
231	struct usbnet *dev = netdev_priv(to_net_dev(d));
232	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
233
234	return sprintf(buf, "%u\n", ctx->timer_interval / (u32)NSEC_PER_USEC);
235}
236
237static ssize_t min_tx_pkt_store(struct device *d,
238				struct device_attribute *attr,
239				const char *buf, size_t len)
240{
241	struct usbnet *dev = netdev_priv(to_net_dev(d));
242	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
243	unsigned long val;
244
245	/* no need to restrict values - anything from 0 to infinity is OK */
246	if (kstrtoul(buf, 0, &val))
247		return -EINVAL;
248
249	ctx->min_tx_pkt = val;
250	return len;
251}
252
253static ssize_t rx_max_store(struct device *d,
254			    struct device_attribute *attr,
255			    const char *buf, size_t len)
256{
257	struct usbnet *dev = netdev_priv(to_net_dev(d));
258	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
259	unsigned long val;
260
261	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_rx_max(dev, val) != val)
262		return -EINVAL;
263
264	cdc_ncm_update_rxtx_max(dev, val, ctx->tx_max);
265	return len;
266}
267
268static ssize_t tx_max_store(struct device *d,
269			    struct device_attribute *attr,
270			    const char *buf, size_t len)
271{
272	struct usbnet *dev = netdev_priv(to_net_dev(d));
273	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
274	unsigned long val;
275
276	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_tx_max(dev, val) != val)
277		return -EINVAL;
278
279	cdc_ncm_update_rxtx_max(dev, ctx->rx_max, val);
280	return len;
281}
282
283static ssize_t tx_timer_usecs_store(struct device *d,
284				    struct device_attribute *attr,
285				    const char *buf, size_t len)
286{
287	struct usbnet *dev = netdev_priv(to_net_dev(d));
288	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
289	ssize_t ret;
290	unsigned long val;
291
292	ret = kstrtoul(buf, 0, &val);
293	if (ret)
294		return ret;
295	if (val && (val < CDC_NCM_TIMER_INTERVAL_MIN || val > CDC_NCM_TIMER_INTERVAL_MAX))
296		return -EINVAL;
297
298	spin_lock_bh(&ctx->mtx);
299	ctx->timer_interval = val * NSEC_PER_USEC;
300	if (!ctx->timer_interval)
301		ctx->tx_timer_pending = 0;
302	spin_unlock_bh(&ctx->mtx);
303	return len;
304}
305
306static DEVICE_ATTR_RW(min_tx_pkt);
307static DEVICE_ATTR_RW(rx_max);
308static DEVICE_ATTR_RW(tx_max);
309static DEVICE_ATTR_RW(tx_timer_usecs);
310
311static ssize_t ndp_to_end_show(struct device *d, struct device_attribute *attr, char *buf)
312{
313	struct usbnet *dev = netdev_priv(to_net_dev(d));
314	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
315
316	return sprintf(buf, "%c\n", ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END ? 'Y' : 'N');
317}
318
319static ssize_t ndp_to_end_store(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
320{
321	struct usbnet *dev = netdev_priv(to_net_dev(d));
322	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
323	bool enable;
324
325	if (kstrtobool(buf, &enable))
326		return -EINVAL;
327
328	/* no change? */
329	if (enable == (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
330		return len;
331
332	if (enable) {
333		if (ctx->is_ndp16 && !ctx->delayed_ndp16) {
334			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
335			if (!ctx->delayed_ndp16)
336				return -ENOMEM;
337		}
338		if (!ctx->is_ndp16 && !ctx->delayed_ndp32) {
339			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
340			if (!ctx->delayed_ndp32)
341				return -ENOMEM;
342		}
343	}
344
345	/* flush pending data before changing flag */
346	netif_tx_lock_bh(dev->net);
347	usbnet_start_xmit(NULL, dev->net);
348	spin_lock_bh(&ctx->mtx);
349	if (enable)
350		ctx->drvflags |= CDC_NCM_FLAG_NDP_TO_END;
351	else
352		ctx->drvflags &= ~CDC_NCM_FLAG_NDP_TO_END;
353	spin_unlock_bh(&ctx->mtx);
354	netif_tx_unlock_bh(dev->net);
355
356	return len;
357}
358static DEVICE_ATTR_RW(ndp_to_end);
359
360#define NCM_PARM_ATTR(name, format, tocpu)				\
361static ssize_t cdc_ncm_show_##name(struct device *d, struct device_attribute *attr, char *buf) \
362{ \
363	struct usbnet *dev = netdev_priv(to_net_dev(d)); \
364	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; \
365	return sprintf(buf, format "\n", tocpu(ctx->ncm_parm.name));	\
366} \
367static DEVICE_ATTR(name, 0444, cdc_ncm_show_##name, NULL)
368
369NCM_PARM_ATTR(bmNtbFormatsSupported, "0x%04x", le16_to_cpu);
370NCM_PARM_ATTR(dwNtbInMaxSize, "%u", le32_to_cpu);
371NCM_PARM_ATTR(wNdpInDivisor, "%u", le16_to_cpu);
372NCM_PARM_ATTR(wNdpInPayloadRemainder, "%u", le16_to_cpu);
373NCM_PARM_ATTR(wNdpInAlignment, "%u", le16_to_cpu);
374NCM_PARM_ATTR(dwNtbOutMaxSize, "%u", le32_to_cpu);
375NCM_PARM_ATTR(wNdpOutDivisor, "%u", le16_to_cpu);
376NCM_PARM_ATTR(wNdpOutPayloadRemainder, "%u", le16_to_cpu);
377NCM_PARM_ATTR(wNdpOutAlignment, "%u", le16_to_cpu);
378NCM_PARM_ATTR(wNtbOutMaxDatagrams, "%u", le16_to_cpu);
379
380static struct attribute *cdc_ncm_sysfs_attrs[] = {
381	&dev_attr_min_tx_pkt.attr,
382	&dev_attr_ndp_to_end.attr,
383	&dev_attr_rx_max.attr,
384	&dev_attr_tx_max.attr,
385	&dev_attr_tx_timer_usecs.attr,
386	&dev_attr_bmNtbFormatsSupported.attr,
387	&dev_attr_dwNtbInMaxSize.attr,
388	&dev_attr_wNdpInDivisor.attr,
389	&dev_attr_wNdpInPayloadRemainder.attr,
390	&dev_attr_wNdpInAlignment.attr,
391	&dev_attr_dwNtbOutMaxSize.attr,
392	&dev_attr_wNdpOutDivisor.attr,
393	&dev_attr_wNdpOutPayloadRemainder.attr,
394	&dev_attr_wNdpOutAlignment.attr,
395	&dev_attr_wNtbOutMaxDatagrams.attr,
396	NULL,
397};
398
399static const struct attribute_group cdc_ncm_sysfs_attr_group = {
400	.name = "cdc_ncm",
401	.attrs = cdc_ncm_sysfs_attrs,
402};
403
404/* handle rx_max and tx_max changes */
405static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx)
406{
407	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
408	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
409	u32 val;
410
411	val = cdc_ncm_check_rx_max(dev, new_rx);
412
413	/* inform device about NTB input size changes */
414	if (val != ctx->rx_max) {
415		__le32 dwNtbInMaxSize = cpu_to_le32(val);
416
417		dev_info(&dev->intf->dev, "setting rx_max = %u\n", val);
418
419		/* tell device to use new size */
420		if (usbnet_write_cmd(dev, USB_CDC_SET_NTB_INPUT_SIZE,
421				     USB_TYPE_CLASS | USB_DIR_OUT
422				     | USB_RECIP_INTERFACE,
423				     0, iface_no, &dwNtbInMaxSize, 4) < 0)
424			dev_dbg(&dev->intf->dev, "Setting NTB Input Size failed\n");
425		else
426			ctx->rx_max = val;
427	}
428
429	/* usbnet use these values for sizing rx queues */
430	if (dev->rx_urb_size != ctx->rx_max) {
431		dev->rx_urb_size = ctx->rx_max;
432		if (netif_running(dev->net))
433			usbnet_unlink_rx_urbs(dev);
434	}
435
436	val = cdc_ncm_check_tx_max(dev, new_tx);
437	if (val != ctx->tx_max)
438		dev_info(&dev->intf->dev, "setting tx_max = %u\n", val);
439
440	/* Adding a pad byte here if necessary simplifies the handling
441	 * in cdc_ncm_fill_tx_frame, making tx_max always represent
442	 * the real skb max size.
443	 *
444	 * We cannot use dev->maxpacket here because this is called from
445	 * .bind which is called before usbnet sets up dev->maxpacket
446	 */
447	if (val != le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) &&
448	    val % usb_maxpacket(dev->udev, dev->out) == 0)
449		val++;
450
451	/* we might need to flush any pending tx buffers if running */
452	if (netif_running(dev->net) && val > ctx->tx_max) {
453		netif_tx_lock_bh(dev->net);
454		usbnet_start_xmit(NULL, dev->net);
455		/* make sure tx_curr_skb is reallocated if it was empty */
456		if (ctx->tx_curr_skb) {
457			dev_kfree_skb_any(ctx->tx_curr_skb);
458			ctx->tx_curr_skb = NULL;
459		}
460		ctx->tx_max = val;
461		netif_tx_unlock_bh(dev->net);
462	} else {
463		ctx->tx_max = val;
464	}
465
466	dev->hard_mtu = ctx->tx_max;
467
468	/* max qlen depend on hard_mtu and rx_urb_size */
469	usbnet_update_max_qlen(dev);
470
471	/* never pad more than 3 full USB packets per transfer */
472	ctx->min_tx_pkt = clamp_t(u16, ctx->tx_max - 3 * usb_maxpacket(dev->udev, dev->out),
473				  CDC_NCM_MIN_TX_PKT, ctx->tx_max);
474}
475
476/* helpers for NCM and MBIM differences */
477static u8 cdc_ncm_flags(struct usbnet *dev)
478{
479	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
480
481	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
482		return ctx->mbim_desc->bmNetworkCapabilities;
483	if (ctx->func_desc)
484		return ctx->func_desc->bmNetworkCapabilities;
485	return 0;
486}
487
488static int cdc_ncm_eth_hlen(struct usbnet *dev)
489{
490	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
491		return 0;
492	return ETH_HLEN;
493}
494
495static u32 cdc_ncm_min_dgram_size(struct usbnet *dev)
496{
497	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
498		return CDC_MBIM_MIN_DATAGRAM_SIZE;
499	return CDC_NCM_MIN_DATAGRAM_SIZE;
500}
501
502static u32 cdc_ncm_max_dgram_size(struct usbnet *dev)
503{
504	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
505
506	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
507		return le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
508	if (ctx->ether_desc)
509		return le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
510	return CDC_NCM_MAX_DATAGRAM_SIZE;
511}
512
513/* initial one-time device setup.  MUST be called with the data interface
514 * in altsetting 0
515 */
516static int cdc_ncm_init(struct usbnet *dev)
517{
518	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
519	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
520	int err;
521
522	err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
523			      USB_TYPE_CLASS | USB_DIR_IN
524			      |USB_RECIP_INTERFACE,
525			      0, iface_no, &ctx->ncm_parm,
526			      sizeof(ctx->ncm_parm));
527	if (err < 0) {
528		dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
529		return err; /* GET_NTB_PARAMETERS is required */
530	}
531
532	/* set CRC Mode */
533	if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
534		dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
535		err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
536				       USB_TYPE_CLASS | USB_DIR_OUT
537				       | USB_RECIP_INTERFACE,
538				       USB_CDC_NCM_CRC_NOT_APPENDED,
539				       iface_no, NULL, 0);
540		if (err < 0)
541			dev_err(&dev->intf->dev, "SET_CRC_MODE failed\n");
542	}
543
544	/* use ndp16 by default */
545	ctx->is_ndp16 = 1;
546
547	/* set NTB format, if both formats are supported.
548	 *
549	 * "The host shall only send this command while the NCM Data
550	 *  Interface is in alternate setting 0."
551	 */
552	if (le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported) &
553						USB_CDC_NCM_NTB32_SUPPORTED) {
554		if (ctx->drvflags & CDC_NCM_FLAG_PREFER_NTB32) {
555			ctx->is_ndp16 = 0;
556			dev_dbg(&dev->intf->dev, "Setting NTB format to 32-bit\n");
557			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
558					       USB_TYPE_CLASS | USB_DIR_OUT
559					       | USB_RECIP_INTERFACE,
560					       USB_CDC_NCM_NTB32_FORMAT,
561					       iface_no, NULL, 0);
562		} else {
563			ctx->is_ndp16 = 1;
564			dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit\n");
565			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
566					       USB_TYPE_CLASS | USB_DIR_OUT
567					       | USB_RECIP_INTERFACE,
568					       USB_CDC_NCM_NTB16_FORMAT,
569					       iface_no, NULL, 0);
570		}
571		if (err < 0) {
572			ctx->is_ndp16 = 1;
573			dev_err(&dev->intf->dev, "SET_NTB_FORMAT failed\n");
574		}
575	}
576
577	/* set initial device values */
578	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
579	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
580	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
581	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
582	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
583	/* devices prior to NCM Errata shall set this field to zero */
584	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
585
586	dev_dbg(&dev->intf->dev,
587		"dwNtbInMaxSize=%u dwNtbOutMaxSize=%u wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
588		ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
589		ctx->tx_ndp_modulus, ctx->tx_max_datagrams, cdc_ncm_flags(dev));
590
591	/* max count of tx datagrams */
592	if ((ctx->tx_max_datagrams == 0) ||
593			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
594		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
595
596	/* set up maximum NDP size */
597	if (ctx->is_ndp16)
598		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp16) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe16);
599	else
600		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp32) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe32);
601
602	/* initial coalescing timer interval */
603	ctx->timer_interval = CDC_NCM_TIMER_INTERVAL_USEC * NSEC_PER_USEC;
604
605	return 0;
606}
607
608/* set a new max datagram size */
609static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
610{
611	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
612	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
613	__le16 max_datagram_size;
614	u16 mbim_mtu;
615	int err;
616
617	/* set default based on descriptors */
618	ctx->max_datagram_size = clamp_t(u32, new_size,
619					 cdc_ncm_min_dgram_size(dev),
620					 CDC_NCM_MAX_DATAGRAM_SIZE);
621
622	/* inform the device about the selected Max Datagram Size? */
623	if (!(cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
624		goto out;
625
626	/* read current mtu value from device */
627	err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
628			      USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
629			      0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
630	if (err != sizeof(max_datagram_size)) {
631		dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
632		goto out;
633	}
634
635	if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
636		goto out;
637
638	max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
639	err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
640			       USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
641			       0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
642	if (err < 0)
643		dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
644
645out:
646	/* set MTU to max supported by the device if necessary */
647	dev->net->mtu = min_t(int, dev->net->mtu, ctx->max_datagram_size - cdc_ncm_eth_hlen(dev));
648
649	/* do not exceed operator preferred MTU */
650	if (ctx->mbim_extended_desc) {
651		mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
652		if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
653			dev->net->mtu = mbim_mtu;
654	}
655}
656
657static void cdc_ncm_fix_modulus(struct usbnet *dev)
658{
659	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
660	u32 val;
661
662	/*
663	 * verify that the structure alignment is:
664	 * - power of two
665	 * - not greater than the maximum transmit length
666	 * - not less than four bytes
667	 */
668	val = ctx->tx_ndp_modulus;
669
670	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
671	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
672		dev_dbg(&dev->intf->dev, "Using default alignment: 4 bytes\n");
673		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
674	}
675
676	/*
677	 * verify that the payload alignment is:
678	 * - power of two
679	 * - not greater than the maximum transmit length
680	 * - not less than four bytes
681	 */
682	val = ctx->tx_modulus;
683
684	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
685	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
686		dev_dbg(&dev->intf->dev, "Using default transmit modulus: 4 bytes\n");
687		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
688	}
689
690	/* verify the payload remainder */
691	if (ctx->tx_remainder >= ctx->tx_modulus) {
692		dev_dbg(&dev->intf->dev, "Using default transmit remainder: 0 bytes\n");
693		ctx->tx_remainder = 0;
694	}
695
696	/* adjust TX-remainder according to NCM specification. */
697	ctx->tx_remainder = ((ctx->tx_remainder - cdc_ncm_eth_hlen(dev)) &
698			     (ctx->tx_modulus - 1));
699}
700
701static int cdc_ncm_setup(struct usbnet *dev)
702{
703	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
704	u32 def_rx, def_tx;
705
706	/* be conservative when selecting initial buffer size to
707	 * increase the number of hosts this will work for
708	 */
709	def_rx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_RX,
710		       le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
711	def_tx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_TX,
712		       le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
713
714	/* clamp rx_max and tx_max and inform device */
715	cdc_ncm_update_rxtx_max(dev, def_rx, def_tx);
716
717	/* sanitize the modulus and remainder values */
718	cdc_ncm_fix_modulus(dev);
719
720	/* set max datagram size */
721	cdc_ncm_set_dgram_size(dev, cdc_ncm_max_dgram_size(dev));
722	return 0;
723}
724
725static void
726cdc_ncm_find_endpoints(struct usbnet *dev, struct usb_interface *intf)
727{
728	struct usb_host_endpoint *e, *in = NULL, *out = NULL;
729	u8 ep;
730
731	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
732		e = intf->cur_altsetting->endpoint + ep;
733
734		/* ignore endpoints which cannot transfer data */
735		if (!usb_endpoint_maxp(&e->desc))
736			continue;
737
738		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
739		case USB_ENDPOINT_XFER_INT:
740			if (usb_endpoint_dir_in(&e->desc)) {
741				if (!dev->status)
742					dev->status = e;
743			}
744			break;
745
746		case USB_ENDPOINT_XFER_BULK:
747			if (usb_endpoint_dir_in(&e->desc)) {
748				if (!in)
749					in = e;
750			} else {
751				if (!out)
752					out = e;
753			}
754			break;
755
756		default:
757			break;
758		}
759	}
760	if (in && !dev->in)
761		dev->in = usb_rcvbulkpipe(dev->udev,
762					  in->desc.bEndpointAddress &
763					  USB_ENDPOINT_NUMBER_MASK);
764	if (out && !dev->out)
765		dev->out = usb_sndbulkpipe(dev->udev,
766					   out->desc.bEndpointAddress &
767					   USB_ENDPOINT_NUMBER_MASK);
768}
769
770static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
771{
772	if (ctx == NULL)
773		return;
774
775	if (ctx->tx_rem_skb != NULL) {
776		dev_kfree_skb_any(ctx->tx_rem_skb);
777		ctx->tx_rem_skb = NULL;
778	}
779
780	if (ctx->tx_curr_skb != NULL) {
781		dev_kfree_skb_any(ctx->tx_curr_skb);
782		ctx->tx_curr_skb = NULL;
783	}
784
785	if (ctx->is_ndp16)
786		kfree(ctx->delayed_ndp16);
787	else
788		kfree(ctx->delayed_ndp32);
789
790	kfree(ctx);
791}
792
793/* we need to override the usbnet change_mtu ndo for two reasons:
794 *  - respect the negotiated maximum datagram size
795 *  - avoid unwanted changes to rx and tx buffers
796 */
797int cdc_ncm_change_mtu(struct net_device *net, int new_mtu)
798{
799	struct usbnet *dev = netdev_priv(net);
800
801	net->mtu = new_mtu;
802	cdc_ncm_set_dgram_size(dev, new_mtu + cdc_ncm_eth_hlen(dev));
803
804	return 0;
805}
806EXPORT_SYMBOL_GPL(cdc_ncm_change_mtu);
807
808static const struct net_device_ops cdc_ncm_netdev_ops = {
809	.ndo_open	     = usbnet_open,
810	.ndo_stop	     = usbnet_stop,
811	.ndo_start_xmit	     = usbnet_start_xmit,
812	.ndo_tx_timeout	     = usbnet_tx_timeout,
813	.ndo_set_rx_mode     = usbnet_set_rx_mode,
814	.ndo_get_stats64     = dev_get_tstats64,
815	.ndo_change_mtu	     = cdc_ncm_change_mtu,
816	.ndo_set_mac_address = eth_mac_addr,
817	.ndo_validate_addr   = eth_validate_addr,
818};
819
820int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting, int drvflags)
821{
822	struct cdc_ncm_ctx *ctx;
823	struct usb_driver *driver;
824	u8 *buf;
825	int len;
826	int temp;
827	u8 iface_no;
828	struct usb_cdc_parsed_header hdr;
829
830	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
831	if (!ctx)
832		return -ENOMEM;
833
834	ctx->dev = dev;
835
836	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
837	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
838	tasklet_setup(&ctx->bh, cdc_ncm_txpath_bh);
839	atomic_set(&ctx->stop, 0);
840	spin_lock_init(&ctx->mtx);
841
842	/* store ctx pointer in device data field */
843	dev->data[0] = (unsigned long)ctx;
844
845	/* only the control interface can be successfully probed */
846	ctx->control = intf;
847
848	/* get some pointers */
849	driver = driver_of(intf);
850	buf = intf->cur_altsetting->extra;
851	len = intf->cur_altsetting->extralen;
852
853	/* parse through descriptors associated with control interface */
854	cdc_parse_cdc_header(&hdr, intf, buf, len);
855
856	if (hdr.usb_cdc_union_desc)
857		ctx->data = usb_ifnum_to_if(dev->udev,
858					    hdr.usb_cdc_union_desc->bSlaveInterface0);
859	ctx->ether_desc = hdr.usb_cdc_ether_desc;
860	ctx->func_desc = hdr.usb_cdc_ncm_desc;
861	ctx->mbim_desc = hdr.usb_cdc_mbim_desc;
862	ctx->mbim_extended_desc = hdr.usb_cdc_mbim_extended_desc;
863
864	/* some buggy devices have an IAD but no CDC Union */
865	if (!hdr.usb_cdc_union_desc && intf->intf_assoc && intf->intf_assoc->bInterfaceCount == 2) {
866		ctx->data = usb_ifnum_to_if(dev->udev, intf->cur_altsetting->desc.bInterfaceNumber + 1);
867		dev_dbg(&intf->dev, "CDC Union missing - got slave from IAD\n");
868	}
869
870	/* check if we got everything */
871	if (!ctx->data) {
872		dev_err(&intf->dev, "CDC Union missing and no IAD found\n");
873		goto error;
874	}
875	if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) {
876		if (!ctx->mbim_desc) {
877			dev_err(&intf->dev, "MBIM functional descriptor missing\n");
878			goto error;
879		}
880	} else {
881		if (!ctx->ether_desc || !ctx->func_desc) {
882			dev_err(&intf->dev, "NCM or ECM functional descriptors missing\n");
883			goto error;
884		}
885	}
886
887	/* claim data interface, if different from control */
888	if (ctx->data != ctx->control) {
889		temp = usb_driver_claim_interface(driver, ctx->data, dev);
890		if (temp) {
891			dev_err(&intf->dev, "failed to claim data intf\n");
892			goto error;
893		}
894	}
895
896	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
897
898	/* Device-specific flags */
899	ctx->drvflags = drvflags;
900
901	/* Reset data interface. Some devices will not reset properly
902	 * unless they are configured first.  Toggle the altsetting to
903	 * force a reset.
904	 * Some other devices do not work properly with this procedure
905	 * that can be avoided using quirk CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE
906	 */
907	if (!(ctx->drvflags & CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE))
908		usb_set_interface(dev->udev, iface_no, data_altsetting);
909
910	temp = usb_set_interface(dev->udev, iface_no, 0);
911	if (temp) {
912		dev_dbg(&intf->dev, "set interface failed\n");
913		goto error2;
914	}
915
916	/* initialize basic device settings */
917	if (cdc_ncm_init(dev))
918		goto error2;
919
920	/* Some firmwares need a pause here or they will silently fail
921	 * to set up the interface properly.  This value was decided
922	 * empirically on a Sierra Wireless MC7455 running 02.08.02.00
923	 * firmware.
924	 */
925	usleep_range(10000, 20000);
926
927	/* configure data interface */
928	temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
929	if (temp) {
930		dev_dbg(&intf->dev, "set interface failed\n");
931		goto error2;
932	}
933
934	cdc_ncm_find_endpoints(dev, ctx->data);
935	cdc_ncm_find_endpoints(dev, ctx->control);
936	if (!dev->in || !dev->out || !dev->status) {
937		dev_dbg(&intf->dev, "failed to collect endpoints\n");
938		goto error2;
939	}
940
941	usb_set_intfdata(ctx->control, dev);
942
943	if (ctx->ether_desc) {
944		temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
945		if (temp) {
946			dev_err(&intf->dev, "failed to get mac address\n");
947			goto error2;
948		}
949		dev_info(&intf->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
950	}
951
952	/* finish setting up the device specific data */
953	cdc_ncm_setup(dev);
954
955	/* Allocate the delayed NDP if needed. */
956	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
957		if (ctx->is_ndp16) {
958			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
959			if (!ctx->delayed_ndp16)
960				goto error2;
961		} else {
962			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
963			if (!ctx->delayed_ndp32)
964				goto error2;
965		}
966		dev_info(&intf->dev, "NDP will be placed at end of frame for this device.");
967	}
968
969	/* override ethtool_ops */
970	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
971
972	/* add our sysfs attrs */
973	dev->net->sysfs_groups[0] = &cdc_ncm_sysfs_attr_group;
974
975	/* must handle MTU changes */
976	dev->net->netdev_ops = &cdc_ncm_netdev_ops;
977	dev->net->max_mtu = cdc_ncm_max_dgram_size(dev) - cdc_ncm_eth_hlen(dev);
978
979	return 0;
980
981error2:
982	usb_set_intfdata(ctx->control, NULL);
983	usb_set_intfdata(ctx->data, NULL);
984	if (ctx->data != ctx->control)
985		usb_driver_release_interface(driver, ctx->data);
986error:
987	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
988	dev->data[0] = 0;
989	dev_info(&intf->dev, "bind() failure\n");
990	return -ENODEV;
991}
992EXPORT_SYMBOL_GPL(cdc_ncm_bind_common);
993
994void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
995{
996	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
997	struct usb_driver *driver = driver_of(intf);
998
999	if (ctx == NULL)
1000		return;		/* no setup */
1001
1002	atomic_set(&ctx->stop, 1);
1003
1004	hrtimer_cancel(&ctx->tx_timer);
1005
1006	tasklet_kill(&ctx->bh);
1007
1008	/* handle devices with combined control and data interface */
1009	if (ctx->control == ctx->data)
1010		ctx->data = NULL;
1011
1012	/* disconnect master --> disconnect slave */
1013	if (intf == ctx->control && ctx->data) {
1014		usb_set_intfdata(ctx->data, NULL);
1015		usb_driver_release_interface(driver, ctx->data);
1016		ctx->data = NULL;
1017
1018	} else if (intf == ctx->data && ctx->control) {
1019		usb_set_intfdata(ctx->control, NULL);
1020		usb_driver_release_interface(driver, ctx->control);
1021		ctx->control = NULL;
1022	}
1023
1024	usb_set_intfdata(intf, NULL);
1025	cdc_ncm_free(ctx);
1026}
1027EXPORT_SYMBOL_GPL(cdc_ncm_unbind);
1028
1029/* Return the number of the MBIM control interface altsetting iff it
1030 * is preferred and available,
1031 */
1032u8 cdc_ncm_select_altsetting(struct usb_interface *intf)
1033{
1034	struct usb_host_interface *alt;
1035
1036	/* The MBIM spec defines a NCM compatible default altsetting,
1037	 * which we may have matched:
1038	 *
1039	 *  "Functions that implement both NCM 1.0 and MBIM (an
1040	 *   ���NCM/MBIM function���) according to this recommendation
1041	 *   shall provide two alternate settings for the
1042	 *   Communication Interface.  Alternate setting 0, and the
1043	 *   associated class and endpoint descriptors, shall be
1044	 *   constructed according to the rules given for the
1045	 *   Communication Interface in section 5 of [USBNCM10].
1046	 *   Alternate setting 1, and the associated class and
1047	 *   endpoint descriptors, shall be constructed according to
1048	 *   the rules given in section 6 (USB Device Model) of this
1049	 *   specification."
1050	 */
1051	if (intf->num_altsetting < 2)
1052		return intf->cur_altsetting->desc.bAlternateSetting;
1053
1054	if (prefer_mbim) {
1055		alt = usb_altnum_to_altsetting(intf, CDC_NCM_COMM_ALTSETTING_MBIM);
1056		if (alt && cdc_ncm_comm_intf_is_mbim(alt))
1057			return CDC_NCM_COMM_ALTSETTING_MBIM;
1058	}
1059	return CDC_NCM_COMM_ALTSETTING_NCM;
1060}
1061EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting);
1062
1063static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
1064{
1065	/* MBIM backwards compatible function? */
1066	if (cdc_ncm_select_altsetting(intf) != CDC_NCM_COMM_ALTSETTING_NCM)
1067		return -ENODEV;
1068
1069	/* The NCM data altsetting is fixed, so we hard-coded it.
1070	 * Additionally, generic NCM devices are assumed to accept arbitrarily
1071	 * placed NDP.
1072	 */
1073	return cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM, 0);
1074}
1075
1076static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max)
1077{
1078	size_t align = ALIGN(skb->len, modulus) - skb->len + remainder;
1079
1080	if (skb->len + align > max)
1081		align = max - skb->len;
1082	if (align && skb_tailroom(skb) >= align)
1083		skb_put_zero(skb, align);
1084}
1085
1086/* return a pointer to a valid struct usb_cdc_ncm_ndp16 of type sign, possibly
1087 * allocating a new one within skb
1088 */
1089static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1090{
1091	struct usb_cdc_ncm_ndp16 *ndp16 = NULL;
1092	struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
1093	size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
1094
1095	/* If NDP should be moved to the end of the NCM package, we can't follow the
1096	* NTH16 header as we would normally do. NDP isn't written to the SKB yet, and
1097	* the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1098	*/
1099	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1100		if (ctx->delayed_ndp16->dwSignature == sign)
1101			return ctx->delayed_ndp16;
1102
1103		/* We can only push a single NDP to the end. Return
1104		 * NULL to send what we've already got and queue this
1105		 * skb for later.
1106		 */
1107		else if (ctx->delayed_ndp16->dwSignature)
1108			return NULL;
1109	}
1110
1111	/* follow the chain of NDPs, looking for a match */
1112	while (ndpoffset) {
1113		ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
1114		if  (ndp16->dwSignature == sign)
1115			return ndp16;
1116		ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1117	}
1118
1119	/* align new NDP */
1120	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1121		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1122
1123	/* verify that there is room for the NDP and the datagram (reserve) */
1124	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1125		return NULL;
1126
1127	/* link to it */
1128	if (ndp16)
1129		ndp16->wNextNdpIndex = cpu_to_le16(skb->len);
1130	else
1131		nth16->wNdpIndex = cpu_to_le16(skb->len);
1132
1133	/* push a new empty NDP */
1134	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1135		ndp16 = skb_put_zero(skb, ctx->max_ndp_size);
1136	else
1137		ndp16 = ctx->delayed_ndp16;
1138
1139	ndp16->dwSignature = sign;
1140	ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
1141	return ndp16;
1142}
1143
1144static struct usb_cdc_ncm_ndp32 *cdc_ncm_ndp32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1145{
1146	struct usb_cdc_ncm_ndp32 *ndp32 = NULL;
1147	struct usb_cdc_ncm_nth32 *nth32 = (void *)skb->data;
1148	size_t ndpoffset = le32_to_cpu(nth32->dwNdpIndex);
1149
1150	/* If NDP should be moved to the end of the NCM package, we can't follow the
1151	 * NTH32 header as we would normally do. NDP isn't written to the SKB yet, and
1152	 * the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1153	 */
1154	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1155		if (ctx->delayed_ndp32->dwSignature == sign)
1156			return ctx->delayed_ndp32;
1157
1158		/* We can only push a single NDP to the end. Return
1159		 * NULL to send what we've already got and queue this
1160		 * skb for later.
1161		 */
1162		else if (ctx->delayed_ndp32->dwSignature)
1163			return NULL;
1164	}
1165
1166	/* follow the chain of NDPs, looking for a match */
1167	while (ndpoffset) {
1168		ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb->data + ndpoffset);
1169		if  (ndp32->dwSignature == sign)
1170			return ndp32;
1171		ndpoffset = le32_to_cpu(ndp32->dwNextNdpIndex);
1172	}
1173
1174	/* align new NDP */
1175	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1176		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1177
1178	/* verify that there is room for the NDP and the datagram (reserve) */
1179	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1180		return NULL;
1181
1182	/* link to it */
1183	if (ndp32)
1184		ndp32->dwNextNdpIndex = cpu_to_le32(skb->len);
1185	else
1186		nth32->dwNdpIndex = cpu_to_le32(skb->len);
1187
1188	/* push a new empty NDP */
1189	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1190		ndp32 = skb_put_zero(skb, ctx->max_ndp_size);
1191	else
1192		ndp32 = ctx->delayed_ndp32;
1193
1194	ndp32->dwSignature = sign;
1195	ndp32->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp32) + sizeof(struct usb_cdc_ncm_dpe32));
1196	return ndp32;
1197}
1198
1199struct sk_buff *
1200cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
1201{
1202	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1203	union {
1204		struct usb_cdc_ncm_nth16 *nth16;
1205		struct usb_cdc_ncm_nth32 *nth32;
1206	} nth;
1207	union {
1208		struct usb_cdc_ncm_ndp16 *ndp16;
1209		struct usb_cdc_ncm_ndp32 *ndp32;
1210	} ndp;
1211	struct sk_buff *skb_out;
1212	u16 n = 0, index, ndplen;
1213	u8 ready2send = 0;
1214	u32 delayed_ndp_size;
1215	size_t padding_count;
1216
1217	/* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated
1218	 * accordingly. Otherwise, we should check here.
1219	 */
1220	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
1221		delayed_ndp_size = ctx->max_ndp_size +
1222			max_t(u32,
1223			      ctx->tx_ndp_modulus,
1224			      ctx->tx_modulus + ctx->tx_remainder) - 1;
1225	else
1226		delayed_ndp_size = 0;
1227
1228	/* if there is a remaining skb, it gets priority */
1229	if (skb != NULL) {
1230		swap(skb, ctx->tx_rem_skb);
1231		swap(sign, ctx->tx_rem_sign);
1232	} else {
1233		ready2send = 1;
1234	}
1235
1236	/* check if we are resuming an OUT skb */
1237	skb_out = ctx->tx_curr_skb;
1238
1239	/* allocate a new OUT skb */
1240	if (!skb_out) {
1241		if (ctx->tx_low_mem_val == 0) {
1242			ctx->tx_curr_size = ctx->tx_max;
1243			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1244			/* If the memory allocation fails we will wait longer
1245			 * each time before attempting another full size
1246			 * allocation again to not overload the system
1247			 * further.
1248			 */
1249			if (skb_out == NULL) {
1250				/* If even the smallest allocation fails, abort. */
1251				if (ctx->tx_curr_size == USB_CDC_NCM_NTB_MIN_OUT_SIZE)
1252					goto alloc_failed;
1253				ctx->tx_low_mem_max_cnt = min(ctx->tx_low_mem_max_cnt + 1,
1254							      (unsigned)CDC_NCM_LOW_MEM_MAX_CNT);
1255				ctx->tx_low_mem_val = ctx->tx_low_mem_max_cnt;
1256			}
1257		}
1258		if (skb_out == NULL) {
1259			/* See if a very small allocation is possible.
1260			 * We will send this packet immediately and hope
1261			 * that there is more memory available later.
1262			 */
1263			if (skb)
1264				ctx->tx_curr_size = max(skb->len,
1265					(u32)USB_CDC_NCM_NTB_MIN_OUT_SIZE);
1266			else
1267				ctx->tx_curr_size = USB_CDC_NCM_NTB_MIN_OUT_SIZE;
1268			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1269
1270			/* No allocation possible so we will abort */
1271			if (!skb_out)
1272				goto alloc_failed;
1273			ctx->tx_low_mem_val--;
1274		}
1275		if (ctx->is_ndp16) {
1276			/* fill out the initial 16-bit NTB header */
1277			nth.nth16 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth16));
1278			nth.nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
1279			nth.nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
1280			nth.nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
1281		} else {
1282			/* fill out the initial 32-bit NTB header */
1283			nth.nth32 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth32));
1284			nth.nth32->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH32_SIGN);
1285			nth.nth32->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth32));
1286			nth.nth32->wSequence = cpu_to_le16(ctx->tx_seq++);
1287		}
1288
1289		/* count total number of frames in this NTB */
1290		ctx->tx_curr_frame_num = 0;
1291
1292		/* recent payload counter for this skb_out */
1293		ctx->tx_curr_frame_payload = 0;
1294	}
1295
1296	for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
1297		/* send any remaining skb first */
1298		if (skb == NULL) {
1299			skb = ctx->tx_rem_skb;
1300			sign = ctx->tx_rem_sign;
1301			ctx->tx_rem_skb = NULL;
1302
1303			/* check for end of skb */
1304			if (skb == NULL)
1305				break;
1306		}
1307
1308		/* get the appropriate NDP for this skb */
1309		if (ctx->is_ndp16)
1310			ndp.ndp16 = cdc_ncm_ndp16(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1311		else
1312			ndp.ndp32 = cdc_ncm_ndp32(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1313
1314		/* align beginning of next frame */
1315		cdc_ncm_align_tail(skb_out,  ctx->tx_modulus, ctx->tx_remainder, ctx->tx_curr_size);
1316
1317		/* check if we had enough room left for both NDP and frame */
1318		if ((ctx->is_ndp16 && !ndp.ndp16) || (!ctx->is_ndp16 && !ndp.ndp32) ||
1319		    skb_out->len + skb->len + delayed_ndp_size > ctx->tx_curr_size) {
1320			if (n == 0) {
1321				/* won't fit, MTU problem? */
1322				dev_kfree_skb_any(skb);
1323				skb = NULL;
1324				dev->net->stats.tx_dropped++;
1325			} else {
1326				/* no room for skb - store for later */
1327				if (ctx->tx_rem_skb != NULL) {
1328					dev_kfree_skb_any(ctx->tx_rem_skb);
1329					dev->net->stats.tx_dropped++;
1330				}
1331				ctx->tx_rem_skb = skb;
1332				ctx->tx_rem_sign = sign;
1333				skb = NULL;
1334				ready2send = 1;
1335				ctx->tx_reason_ntb_full++;	/* count reason for transmitting */
1336			}
1337			break;
1338		}
1339
1340		/* calculate frame number within this NDP */
1341		if (ctx->is_ndp16) {
1342			ndplen = le16_to_cpu(ndp.ndp16->wLength);
1343			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
1344
1345			/* OK, add this skb */
1346			ndp.ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
1347			ndp.ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
1348			ndp.ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
1349		} else {
1350			ndplen = le16_to_cpu(ndp.ndp32->wLength);
1351			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp32)) / sizeof(struct usb_cdc_ncm_dpe32) - 1;
1352
1353			ndp.ndp32->dpe32[index].dwDatagramLength = cpu_to_le32(skb->len);
1354			ndp.ndp32->dpe32[index].dwDatagramIndex = cpu_to_le32(skb_out->len);
1355			ndp.ndp32->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe32));
1356		}
1357		skb_put_data(skb_out, skb->data, skb->len);
1358		ctx->tx_curr_frame_payload += skb->len;	/* count real tx payload data */
1359		dev_kfree_skb_any(skb);
1360		skb = NULL;
1361
1362		/* send now if this NDP is full */
1363		if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
1364			ready2send = 1;
1365			ctx->tx_reason_ndp_full++;	/* count reason for transmitting */
1366			break;
1367		}
1368	}
1369
1370	/* free up any dangling skb */
1371	if (skb != NULL) {
1372		dev_kfree_skb_any(skb);
1373		skb = NULL;
1374		dev->net->stats.tx_dropped++;
1375	}
1376
1377	ctx->tx_curr_frame_num = n;
1378
1379	if (n == 0) {
1380		/* wait for more frames */
1381		/* push variables */
1382		ctx->tx_curr_skb = skb_out;
1383		goto exit_no_skb;
1384
1385	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0) && (ctx->timer_interval > 0)) {
1386		/* wait for more frames */
1387		/* push variables */
1388		ctx->tx_curr_skb = skb_out;
1389		/* set the pending count */
1390		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
1391			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
1392		goto exit_no_skb;
1393
1394	} else {
1395		if (n == ctx->tx_max_datagrams)
1396			ctx->tx_reason_max_datagram++;	/* count reason for transmitting */
1397		/* frame goes out */
1398		/* variables will be reset at next call */
1399	}
1400
1401	/* If requested, put NDP at end of frame. */
1402	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1403		if (ctx->is_ndp16) {
1404			nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1405			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1406			nth.nth16->wNdpIndex = cpu_to_le16(skb_out->len);
1407			skb_put_data(skb_out, ctx->delayed_ndp16, ctx->max_ndp_size);
1408
1409			/* Zero out delayed NDP - signature checking will naturally fail. */
1410			ndp.ndp16 = memset(ctx->delayed_ndp16, 0, ctx->max_ndp_size);
1411		} else {
1412			nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1413			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1414			nth.nth32->dwNdpIndex = cpu_to_le32(skb_out->len);
1415			skb_put_data(skb_out, ctx->delayed_ndp32, ctx->max_ndp_size);
1416
1417			ndp.ndp32 = memset(ctx->delayed_ndp32, 0, ctx->max_ndp_size);
1418		}
1419	}
1420
1421	/* If collected data size is less or equal ctx->min_tx_pkt
1422	 * bytes, we send buffers as it is. If we get more data, it
1423	 * would be more efficient for USB HS mobile device with DMA
1424	 * engine to receive a full size NTB, than canceling DMA
1425	 * transfer and receiving a short packet.
1426	 *
1427	 * This optimization support is pointless if we end up sending
1428	 * a ZLP after full sized NTBs.
1429	 */
1430	if (!(dev->driver_info->flags & FLAG_SEND_ZLP) &&
1431	    skb_out->len > ctx->min_tx_pkt) {
1432		padding_count = ctx->tx_curr_size - skb_out->len;
1433		if (!WARN_ON(padding_count > ctx->tx_curr_size))
1434			skb_put_zero(skb_out, padding_count);
1435	} else if (skb_out->len < ctx->tx_curr_size &&
1436		   (skb_out->len % dev->maxpacket) == 0) {
1437		skb_put_u8(skb_out, 0);	/* force short packet */
1438	}
1439
1440	/* set final frame length */
1441	if (ctx->is_ndp16) {
1442		nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1443		nth.nth16->wBlockLength = cpu_to_le16(skb_out->len);
1444	} else {
1445		nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1446		nth.nth32->dwBlockLength = cpu_to_le32(skb_out->len);
1447	}
1448
1449	/* return skb */
1450	ctx->tx_curr_skb = NULL;
1451
1452	/* keep private stats: framing overhead and number of NTBs */
1453	ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
1454	ctx->tx_ntbs++;
1455
1456	/* usbnet will count all the framing overhead by default.
1457	 * Adjust the stats so that the tx_bytes counter show real
1458	 * payload data instead.
1459	 */
1460	usbnet_set_skb_tx_stats(skb_out, n,
1461				(long)ctx->tx_curr_frame_payload - skb_out->len);
1462
1463	return skb_out;
1464
1465alloc_failed:
1466	if (skb) {
1467		dev_kfree_skb_any(skb);
1468		dev->net->stats.tx_dropped++;
1469	}
1470exit_no_skb:
1471	/* Start timer, if there is a remaining non-empty skb */
1472	if (ctx->tx_curr_skb != NULL && n > 0)
1473		cdc_ncm_tx_timeout_start(ctx);
1474	return NULL;
1475}
1476EXPORT_SYMBOL_GPL(cdc_ncm_fill_tx_frame);
1477
1478static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
1479{
1480	/* start timer, if not already started */
1481	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
1482		hrtimer_start(&ctx->tx_timer,
1483				ctx->timer_interval,
1484				HRTIMER_MODE_REL);
1485}
1486
1487static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
1488{
1489	struct cdc_ncm_ctx *ctx =
1490			container_of(timer, struct cdc_ncm_ctx, tx_timer);
1491
1492	if (!atomic_read(&ctx->stop))
1493		tasklet_schedule(&ctx->bh);
1494	return HRTIMER_NORESTART;
1495}
1496
1497static void cdc_ncm_txpath_bh(struct tasklet_struct *t)
1498{
1499	struct cdc_ncm_ctx *ctx = from_tasklet(ctx, t, bh);
1500	struct usbnet *dev = ctx->dev;
1501
1502	spin_lock(&ctx->mtx);
1503	if (ctx->tx_timer_pending != 0) {
1504		ctx->tx_timer_pending--;
1505		cdc_ncm_tx_timeout_start(ctx);
1506		spin_unlock(&ctx->mtx);
1507	} else if (dev->net != NULL) {
1508		ctx->tx_reason_timeout++;	/* count reason for transmitting */
1509		spin_unlock(&ctx->mtx);
1510		netif_tx_lock_bh(dev->net);
1511		usbnet_start_xmit(NULL, dev->net);
1512		netif_tx_unlock_bh(dev->net);
1513	} else {
1514		spin_unlock(&ctx->mtx);
1515	}
1516}
1517
1518struct sk_buff *
1519cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
1520{
1521	struct sk_buff *skb_out;
1522	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1523
1524	/*
1525	 * The Ethernet API we are using does not support transmitting
1526	 * multiple Ethernet frames in a single call. This driver will
1527	 * accumulate multiple Ethernet frames and send out a larger
1528	 * USB frame when the USB buffer is full or when a single jiffies
1529	 * timeout happens.
1530	 */
1531	if (ctx == NULL)
1532		goto error;
1533
1534	spin_lock_bh(&ctx->mtx);
1535
1536	if (ctx->is_ndp16)
1537		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN));
1538	else
1539		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN));
1540
1541	spin_unlock_bh(&ctx->mtx);
1542	return skb_out;
1543
1544error:
1545	if (skb != NULL)
1546		dev_kfree_skb_any(skb);
1547
1548	return NULL;
1549}
1550EXPORT_SYMBOL_GPL(cdc_ncm_tx_fixup);
1551
1552/* verify NTB header and return offset of first NDP, or negative error */
1553int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1554{
1555	struct usbnet *dev = netdev_priv(skb_in->dev);
1556	struct usb_cdc_ncm_nth16 *nth16;
1557	int len;
1558	int ret = -EINVAL;
1559
1560	if (ctx == NULL)
1561		goto error;
1562
1563	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
1564					sizeof(struct usb_cdc_ncm_ndp16))) {
1565		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1566		goto error;
1567	}
1568
1569	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
1570
1571	if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
1572		netif_dbg(dev, rx_err, dev->net,
1573			  "invalid NTH16 signature <%#010x>\n",
1574			  le32_to_cpu(nth16->dwSignature));
1575		goto error;
1576	}
1577
1578	len = le16_to_cpu(nth16->wBlockLength);
1579	if (len > ctx->rx_max) {
1580		netif_dbg(dev, rx_err, dev->net,
1581			  "unsupported NTB block length %u/%u\n", len,
1582			  ctx->rx_max);
1583		goto error;
1584	}
1585
1586	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
1587	    (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
1588	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
1589		netif_dbg(dev, rx_err, dev->net,
1590			  "sequence number glitch prev=%d curr=%d\n",
1591			  ctx->rx_seq, le16_to_cpu(nth16->wSequence));
1592	}
1593	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
1594
1595	ret = le16_to_cpu(nth16->wNdpIndex);
1596error:
1597	return ret;
1598}
1599EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth16);
1600
1601int cdc_ncm_rx_verify_nth32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1602{
1603	struct usbnet *dev = netdev_priv(skb_in->dev);
1604	struct usb_cdc_ncm_nth32 *nth32;
1605	int len;
1606	int ret = -EINVAL;
1607
1608	if (ctx == NULL)
1609		goto error;
1610
1611	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth32) +
1612					sizeof(struct usb_cdc_ncm_ndp32))) {
1613		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1614		goto error;
1615	}
1616
1617	nth32 = (struct usb_cdc_ncm_nth32 *)skb_in->data;
1618
1619	if (nth32->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH32_SIGN)) {
1620		netif_dbg(dev, rx_err, dev->net,
1621			  "invalid NTH32 signature <%#010x>\n",
1622			  le32_to_cpu(nth32->dwSignature));
1623		goto error;
1624	}
1625
1626	len = le32_to_cpu(nth32->dwBlockLength);
1627	if (len > ctx->rx_max) {
1628		netif_dbg(dev, rx_err, dev->net,
1629			  "unsupported NTB block length %u/%u\n", len,
1630			  ctx->rx_max);
1631		goto error;
1632	}
1633
1634	if ((ctx->rx_seq + 1) != le16_to_cpu(nth32->wSequence) &&
1635	    (ctx->rx_seq || le16_to_cpu(nth32->wSequence)) &&
1636	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth32->wSequence))) {
1637		netif_dbg(dev, rx_err, dev->net,
1638			  "sequence number glitch prev=%d curr=%d\n",
1639			  ctx->rx_seq, le16_to_cpu(nth32->wSequence));
1640	}
1641	ctx->rx_seq = le16_to_cpu(nth32->wSequence);
1642
1643	ret = le32_to_cpu(nth32->dwNdpIndex);
1644error:
1645	return ret;
1646}
1647EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth32);
1648
1649/* verify NDP header and return number of datagrams, or negative error */
1650int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
1651{
1652	struct usbnet *dev = netdev_priv(skb_in->dev);
1653	struct usb_cdc_ncm_ndp16 *ndp16;
1654	int ret = -EINVAL;
1655
1656	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
1657		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1658			  ndpoffset);
1659		goto error;
1660	}
1661	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1662
1663	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1664		netif_dbg(dev, rx_err, dev->net, "invalid DPT16 length <%u>\n",
1665			  le16_to_cpu(ndp16->wLength));
1666		goto error;
1667	}
1668
1669	ret = ((le16_to_cpu(ndp16->wLength) -
1670					sizeof(struct usb_cdc_ncm_ndp16)) /
1671					sizeof(struct usb_cdc_ncm_dpe16));
1672	ret--; /* we process NDP entries except for the last one */
1673
1674	if ((sizeof(struct usb_cdc_ncm_ndp16) +
1675	     ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) {
1676		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1677		ret = -EINVAL;
1678	}
1679
1680error:
1681	return ret;
1682}
1683EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp16);
1684
1685/* verify NDP header and return number of datagrams, or negative error */
1686int cdc_ncm_rx_verify_ndp32(struct sk_buff *skb_in, int ndpoffset)
1687{
1688	struct usbnet *dev = netdev_priv(skb_in->dev);
1689	struct usb_cdc_ncm_ndp32 *ndp32;
1690	int ret = -EINVAL;
1691
1692	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp32)) > skb_in->len) {
1693		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1694			  ndpoffset);
1695		goto error;
1696	}
1697	ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1698
1699	if (le16_to_cpu(ndp32->wLength) < USB_CDC_NCM_NDP32_LENGTH_MIN) {
1700		netif_dbg(dev, rx_err, dev->net, "invalid DPT32 length <%u>\n",
1701			  le16_to_cpu(ndp32->wLength));
1702		goto error;
1703	}
1704
1705	ret = ((le16_to_cpu(ndp32->wLength) -
1706					sizeof(struct usb_cdc_ncm_ndp32)) /
1707					sizeof(struct usb_cdc_ncm_dpe32));
1708	ret--; /* we process NDP entries except for the last one */
1709
1710	if ((sizeof(struct usb_cdc_ncm_ndp32) +
1711	     ret * (sizeof(struct usb_cdc_ncm_dpe32))) > skb_in->len) {
1712		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1713		ret = -EINVAL;
1714	}
1715
1716error:
1717	return ret;
1718}
1719EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp32);
1720
1721int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
1722{
1723	struct sk_buff *skb;
1724	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1725	unsigned int len;
1726	int nframes;
1727	int x;
1728	unsigned int offset;
1729	union {
1730		struct usb_cdc_ncm_ndp16 *ndp16;
1731		struct usb_cdc_ncm_ndp32 *ndp32;
1732	} ndp;
1733	union {
1734		struct usb_cdc_ncm_dpe16 *dpe16;
1735		struct usb_cdc_ncm_dpe32 *dpe32;
1736	} dpe;
1737
1738	int ndpoffset;
1739	int loopcount = 50; /* arbitrary max preventing infinite loop */
1740	u32 payload = 0;
1741
1742	if (ctx->is_ndp16)
1743		ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
1744	else
1745		ndpoffset = cdc_ncm_rx_verify_nth32(ctx, skb_in);
1746
1747	if (ndpoffset < 0)
1748		goto error;
1749
1750next_ndp:
1751	if (ctx->is_ndp16) {
1752		nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
1753		if (nframes < 0)
1754			goto error;
1755
1756		ndp.ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1757
1758		if (ndp.ndp16->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) {
1759			netif_dbg(dev, rx_err, dev->net,
1760				  "invalid DPT16 signature <%#010x>\n",
1761				  le32_to_cpu(ndp.ndp16->dwSignature));
1762			goto err_ndp;
1763		}
1764		dpe.dpe16 = ndp.ndp16->dpe16;
1765	} else {
1766		nframes = cdc_ncm_rx_verify_ndp32(skb_in, ndpoffset);
1767		if (nframes < 0)
1768			goto error;
1769
1770		ndp.ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1771
1772		if (ndp.ndp32->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN)) {
1773			netif_dbg(dev, rx_err, dev->net,
1774				  "invalid DPT32 signature <%#010x>\n",
1775				  le32_to_cpu(ndp.ndp32->dwSignature));
1776			goto err_ndp;
1777		}
1778		dpe.dpe32 = ndp.ndp32->dpe32;
1779	}
1780
1781	for (x = 0; x < nframes; x++) {
1782		if (ctx->is_ndp16) {
1783			offset = le16_to_cpu(dpe.dpe16->wDatagramIndex);
1784			len = le16_to_cpu(dpe.dpe16->wDatagramLength);
1785		} else {
1786			offset = le32_to_cpu(dpe.dpe32->dwDatagramIndex);
1787			len = le32_to_cpu(dpe.dpe32->dwDatagramLength);
1788		}
1789
1790		/*
1791		 * CDC NCM ch. 3.7
1792		 * All entries after first NULL entry are to be ignored
1793		 */
1794		if ((offset == 0) || (len == 0)) {
1795			if (!x)
1796				goto err_ndp; /* empty NTB */
1797			break;
1798		}
1799
1800		/* sanity checking - watch out for integer wrap*/
1801		if ((offset > skb_in->len) || (len > skb_in->len - offset) ||
1802				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1803			netif_dbg(dev, rx_err, dev->net,
1804				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
1805				  x, offset, len, skb_in);
1806			if (!x)
1807				goto err_ndp;
1808			break;
1809
1810		} else {
1811			/* create a fresh copy to reduce truesize */
1812			skb = netdev_alloc_skb_ip_align(dev->net,  len);
1813			if (!skb)
1814				goto error;
1815			skb_put_data(skb, skb_in->data + offset, len);
1816			usbnet_skb_return(dev, skb);
1817			payload += len;	/* count payload bytes in this NTB */
1818		}
1819
1820		if (ctx->is_ndp16)
1821			dpe.dpe16++;
1822		else
1823			dpe.dpe32++;
1824	}
1825err_ndp:
1826	/* are there more NDPs to process? */
1827	if (ctx->is_ndp16)
1828		ndpoffset = le16_to_cpu(ndp.ndp16->wNextNdpIndex);
1829	else
1830		ndpoffset = le32_to_cpu(ndp.ndp32->dwNextNdpIndex);
1831
1832	if (ndpoffset && loopcount--)
1833		goto next_ndp;
1834
1835	/* update stats */
1836	ctx->rx_overhead += skb_in->len - payload;
1837	ctx->rx_ntbs++;
1838
1839	return 1;
1840error:
1841	return 0;
1842}
1843EXPORT_SYMBOL_GPL(cdc_ncm_rx_fixup);
1844
1845static void
1846cdc_ncm_speed_change(struct usbnet *dev,
1847		     struct usb_cdc_speed_change *data)
1848{
1849	/* RTL8156 shipped before 2021 sends notification about every 32ms. */
1850	dev->rx_speed = le32_to_cpu(data->DLBitRRate);
1851	dev->tx_speed = le32_to_cpu(data->ULBitRate);
1852}
1853
1854static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1855{
1856	struct usb_cdc_notification *event;
1857
1858	if (urb->actual_length < sizeof(*event))
1859		return;
1860
1861	/* test for split data in 8-byte chunks */
1862	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1863		cdc_ncm_speed_change(dev,
1864		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1865		return;
1866	}
1867
1868	event = urb->transfer_buffer;
1869
1870	switch (event->bNotificationType) {
1871	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1872		/*
1873		 * According to the CDC NCM specification ch.7.1
1874		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1875		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1876		 */
1877		/* RTL8156 shipped before 2021 sends notification about
1878		 * every 32ms. Don't forward notification if state is same.
1879		 */
1880		if (netif_carrier_ok(dev->net) != !!event->wValue)
1881			usbnet_link_change(dev, !!event->wValue, 0);
1882		break;
1883
1884	case USB_CDC_NOTIFY_SPEED_CHANGE:
1885		if (urb->actual_length < (sizeof(*event) +
1886					sizeof(struct usb_cdc_speed_change)))
1887			set_bit(EVENT_STS_SPLIT, &dev->flags);
1888		else
1889			cdc_ncm_speed_change(dev,
1890					     (struct usb_cdc_speed_change *)&event[1]);
1891		break;
1892
1893	default:
1894		dev_dbg(&dev->udev->dev,
1895			"NCM: unexpected notification 0x%02x!\n",
1896			event->bNotificationType);
1897		break;
1898	}
1899}
1900
1901static const struct driver_info cdc_ncm_info = {
1902	.description = "CDC NCM (NO ZLP)",
1903	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1904			| FLAG_LINK_INTR | FLAG_ETHER,
1905	.bind = cdc_ncm_bind,
1906	.unbind = cdc_ncm_unbind,
1907	.manage_power = usbnet_manage_power,
1908	.status = cdc_ncm_status,
1909	.rx_fixup = cdc_ncm_rx_fixup,
1910	.tx_fixup = cdc_ncm_tx_fixup,
1911	.set_rx_mode = usbnet_cdc_update_filter,
1912};
1913
1914/* Same as cdc_ncm_info, but with FLAG_SEND_ZLP  */
1915static const struct driver_info cdc_ncm_zlp_info = {
1916	.description = "CDC NCM (SEND ZLP)",
1917	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1918			| FLAG_LINK_INTR | FLAG_ETHER | FLAG_SEND_ZLP,
1919	.bind = cdc_ncm_bind,
1920	.unbind = cdc_ncm_unbind,
1921	.manage_power = usbnet_manage_power,
1922	.status = cdc_ncm_status,
1923	.rx_fixup = cdc_ncm_rx_fixup,
1924	.tx_fixup = cdc_ncm_tx_fixup,
1925	.set_rx_mode = usbnet_cdc_update_filter,
1926};
1927
1928/* Same as cdc_ncm_info, but with FLAG_WWAN */
1929static const struct driver_info wwan_info = {
1930	.description = "Mobile Broadband Network Device",
1931	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1932			| FLAG_LINK_INTR | FLAG_WWAN,
1933	.bind = cdc_ncm_bind,
1934	.unbind = cdc_ncm_unbind,
1935	.manage_power = usbnet_manage_power,
1936	.status = cdc_ncm_status,
1937	.rx_fixup = cdc_ncm_rx_fixup,
1938	.tx_fixup = cdc_ncm_tx_fixup,
1939	.set_rx_mode = usbnet_cdc_update_filter,
1940};
1941
1942/* Same as wwan_info, but with FLAG_NOARP  */
1943static const struct driver_info wwan_noarp_info = {
1944	.description = "Mobile Broadband Network Device (NO ARP)",
1945	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1946			| FLAG_LINK_INTR | FLAG_WWAN | FLAG_NOARP,
1947	.bind = cdc_ncm_bind,
1948	.unbind = cdc_ncm_unbind,
1949	.manage_power = usbnet_manage_power,
1950	.status = cdc_ncm_status,
1951	.rx_fixup = cdc_ncm_rx_fixup,
1952	.tx_fixup = cdc_ncm_tx_fixup,
1953	.set_rx_mode = usbnet_cdc_update_filter,
1954};
1955
1956static const struct usb_device_id cdc_devs[] = {
1957	/* Ericsson MBM devices like F5521gw */
1958	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1959		| USB_DEVICE_ID_MATCH_VENDOR,
1960	  .idVendor = 0x0bdb,
1961	  .bInterfaceClass = USB_CLASS_COMM,
1962	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1963	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1964	  .driver_info = (unsigned long) &wwan_info,
1965	},
1966
1967	/* Telit LE910 V2 */
1968	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x0036,
1969		USB_CLASS_COMM,
1970		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1971	  .driver_info = (unsigned long)&wwan_noarp_info,
1972	},
1973
1974	/* DW5812 LTE Verizon Mobile Broadband Card
1975	 * Unlike DW5550 this device requires FLAG_NOARP
1976	 */
1977	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bb,
1978		USB_CLASS_COMM,
1979		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1980	  .driver_info = (unsigned long)&wwan_noarp_info,
1981	},
1982
1983	/* DW5813 LTE AT&T Mobile Broadband Card
1984	 * Unlike DW5550 this device requires FLAG_NOARP
1985	 */
1986	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bc,
1987		USB_CLASS_COMM,
1988		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1989	  .driver_info = (unsigned long)&wwan_noarp_info,
1990	},
1991
1992	/* Dell branded MBM devices like DW5550 */
1993	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1994		| USB_DEVICE_ID_MATCH_VENDOR,
1995	  .idVendor = 0x413c,
1996	  .bInterfaceClass = USB_CLASS_COMM,
1997	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1998	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1999	  .driver_info = (unsigned long) &wwan_info,
2000	},
2001
2002	/* Toshiba branded MBM devices */
2003	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
2004		| USB_DEVICE_ID_MATCH_VENDOR,
2005	  .idVendor = 0x0930,
2006	  .bInterfaceClass = USB_CLASS_COMM,
2007	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
2008	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
2009	  .driver_info = (unsigned long) &wwan_info,
2010	},
2011
2012	/* tag Huawei devices as wwan */
2013	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1,
2014					USB_CLASS_COMM,
2015					USB_CDC_SUBCLASS_NCM,
2016					USB_CDC_PROTO_NONE),
2017	  .driver_info = (unsigned long)&wwan_info,
2018	},
2019
2020	/* Infineon(now Intel) HSPA Modem platform */
2021	{ USB_DEVICE_AND_INTERFACE_INFO(0x1519, 0x0443,
2022		USB_CLASS_COMM,
2023		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2024	  .driver_info = (unsigned long)&wwan_noarp_info,
2025	},
2026
2027	/* u-blox TOBY-L4 */
2028	{ USB_DEVICE_AND_INTERFACE_INFO(0x1546, 0x1010,
2029		USB_CLASS_COMM,
2030		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2031	  .driver_info = (unsigned long)&wwan_info,
2032	},
2033
2034	/* DisplayLink docking stations */
2035	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
2036		| USB_DEVICE_ID_MATCH_VENDOR,
2037	  .idVendor = 0x17e9,
2038	  .bInterfaceClass = USB_CLASS_COMM,
2039	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
2040	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
2041	  .driver_info = (unsigned long)&cdc_ncm_zlp_info,
2042	},
2043
2044	/* Generic CDC-NCM devices */
2045	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
2046		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2047		.driver_info = (unsigned long)&cdc_ncm_info,
2048	},
2049	{
2050	},
2051};
2052MODULE_DEVICE_TABLE(usb, cdc_devs);
2053
2054static struct usb_driver cdc_ncm_driver = {
2055	.name = "cdc_ncm",
2056	.id_table = cdc_devs,
2057	.probe = usbnet_probe,
2058	.disconnect = usbnet_disconnect,
2059	.suspend = usbnet_suspend,
2060	.resume = usbnet_resume,
2061	.reset_resume =	usbnet_resume,
2062	.supports_autosuspend = 1,
2063	.disable_hub_initiated_lpm = 1,
2064};
2065
2066module_usb_driver(cdc_ncm_driver);
2067
2068MODULE_AUTHOR("Hans Petter Selasky");
2069MODULE_DESCRIPTION("USB CDC NCM host driver");
2070MODULE_LICENSE("Dual BSD/GPL");
2071