xref: /openbmc/linux/drivers/net/usb/smsc95xx.c (revision b595076a)
1  /***************************************************************************
2  *
3  * Copyright (C) 2007-2008 SMSC
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
18  *
19  *****************************************************************************/
20 
21 #include <linux/module.h>
22 #include <linux/kmod.h>
23 #include <linux/init.h>
24 #include <linux/netdevice.h>
25 #include <linux/etherdevice.h>
26 #include <linux/ethtool.h>
27 #include <linux/mii.h>
28 #include <linux/usb.h>
29 #include <linux/crc32.h>
30 #include <linux/usb/usbnet.h>
31 #include <linux/slab.h>
32 #include "smsc95xx.h"
33 
34 #define SMSC_CHIPNAME			"smsc95xx"
35 #define SMSC_DRIVER_VERSION		"1.0.4"
36 #define HS_USB_PKT_SIZE			(512)
37 #define FS_USB_PKT_SIZE			(64)
38 #define DEFAULT_HS_BURST_CAP_SIZE	(16 * 1024 + 5 * HS_USB_PKT_SIZE)
39 #define DEFAULT_FS_BURST_CAP_SIZE	(6 * 1024 + 33 * FS_USB_PKT_SIZE)
40 #define DEFAULT_BULK_IN_DELAY		(0x00002000)
41 #define MAX_SINGLE_PACKET_SIZE		(2048)
42 #define LAN95XX_EEPROM_MAGIC		(0x9500)
43 #define EEPROM_MAC_OFFSET		(0x01)
44 #define DEFAULT_TX_CSUM_ENABLE		(true)
45 #define DEFAULT_RX_CSUM_ENABLE		(true)
46 #define SMSC95XX_INTERNAL_PHY_ID	(1)
47 #define SMSC95XX_TX_OVERHEAD		(8)
48 #define SMSC95XX_TX_OVERHEAD_CSUM	(12)
49 
50 struct smsc95xx_priv {
51 	u32 mac_cr;
52 	spinlock_t mac_cr_lock;
53 	bool use_tx_csum;
54 	bool use_rx_csum;
55 };
56 
57 struct usb_context {
58 	struct usb_ctrlrequest req;
59 	struct usbnet *dev;
60 };
61 
62 static int turbo_mode = true;
63 module_param(turbo_mode, bool, 0644);
64 MODULE_PARM_DESC(turbo_mode, "Enable multiple frames per Rx transaction");
65 
66 static int smsc95xx_read_reg(struct usbnet *dev, u32 index, u32 *data)
67 {
68 	u32 *buf = kmalloc(4, GFP_KERNEL);
69 	int ret;
70 
71 	BUG_ON(!dev);
72 
73 	if (!buf)
74 		return -ENOMEM;
75 
76 	ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
77 		USB_VENDOR_REQUEST_READ_REGISTER,
78 		USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
79 		00, index, buf, 4, USB_CTRL_GET_TIMEOUT);
80 
81 	if (unlikely(ret < 0))
82 		netdev_warn(dev->net, "Failed to read register index 0x%08x\n", index);
83 
84 	le32_to_cpus(buf);
85 	*data = *buf;
86 	kfree(buf);
87 
88 	return ret;
89 }
90 
91 static int smsc95xx_write_reg(struct usbnet *dev, u32 index, u32 data)
92 {
93 	u32 *buf = kmalloc(4, GFP_KERNEL);
94 	int ret;
95 
96 	BUG_ON(!dev);
97 
98 	if (!buf)
99 		return -ENOMEM;
100 
101 	*buf = data;
102 	cpu_to_le32s(buf);
103 
104 	ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
105 		USB_VENDOR_REQUEST_WRITE_REGISTER,
106 		USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
107 		00, index, buf, 4, USB_CTRL_SET_TIMEOUT);
108 
109 	if (unlikely(ret < 0))
110 		netdev_warn(dev->net, "Failed to write register index 0x%08x\n", index);
111 
112 	kfree(buf);
113 
114 	return ret;
115 }
116 
117 /* Loop until the read is completed with timeout
118  * called with phy_mutex held */
119 static int smsc95xx_phy_wait_not_busy(struct usbnet *dev)
120 {
121 	unsigned long start_time = jiffies;
122 	u32 val;
123 
124 	do {
125 		smsc95xx_read_reg(dev, MII_ADDR, &val);
126 		if (!(val & MII_BUSY_))
127 			return 0;
128 	} while (!time_after(jiffies, start_time + HZ));
129 
130 	return -EIO;
131 }
132 
133 static int smsc95xx_mdio_read(struct net_device *netdev, int phy_id, int idx)
134 {
135 	struct usbnet *dev = netdev_priv(netdev);
136 	u32 val, addr;
137 
138 	mutex_lock(&dev->phy_mutex);
139 
140 	/* confirm MII not busy */
141 	if (smsc95xx_phy_wait_not_busy(dev)) {
142 		netdev_warn(dev->net, "MII is busy in smsc95xx_mdio_read\n");
143 		mutex_unlock(&dev->phy_mutex);
144 		return -EIO;
145 	}
146 
147 	/* set the address, index & direction (read from PHY) */
148 	phy_id &= dev->mii.phy_id_mask;
149 	idx &= dev->mii.reg_num_mask;
150 	addr = (phy_id << 11) | (idx << 6) | MII_READ_;
151 	smsc95xx_write_reg(dev, MII_ADDR, addr);
152 
153 	if (smsc95xx_phy_wait_not_busy(dev)) {
154 		netdev_warn(dev->net, "Timed out reading MII reg %02X\n", idx);
155 		mutex_unlock(&dev->phy_mutex);
156 		return -EIO;
157 	}
158 
159 	smsc95xx_read_reg(dev, MII_DATA, &val);
160 
161 	mutex_unlock(&dev->phy_mutex);
162 
163 	return (u16)(val & 0xFFFF);
164 }
165 
166 static void smsc95xx_mdio_write(struct net_device *netdev, int phy_id, int idx,
167 				int regval)
168 {
169 	struct usbnet *dev = netdev_priv(netdev);
170 	u32 val, addr;
171 
172 	mutex_lock(&dev->phy_mutex);
173 
174 	/* confirm MII not busy */
175 	if (smsc95xx_phy_wait_not_busy(dev)) {
176 		netdev_warn(dev->net, "MII is busy in smsc95xx_mdio_write\n");
177 		mutex_unlock(&dev->phy_mutex);
178 		return;
179 	}
180 
181 	val = regval;
182 	smsc95xx_write_reg(dev, MII_DATA, val);
183 
184 	/* set the address, index & direction (write to PHY) */
185 	phy_id &= dev->mii.phy_id_mask;
186 	idx &= dev->mii.reg_num_mask;
187 	addr = (phy_id << 11) | (idx << 6) | MII_WRITE_;
188 	smsc95xx_write_reg(dev, MII_ADDR, addr);
189 
190 	if (smsc95xx_phy_wait_not_busy(dev))
191 		netdev_warn(dev->net, "Timed out writing MII reg %02X\n", idx);
192 
193 	mutex_unlock(&dev->phy_mutex);
194 }
195 
196 static int smsc95xx_wait_eeprom(struct usbnet *dev)
197 {
198 	unsigned long start_time = jiffies;
199 	u32 val;
200 
201 	do {
202 		smsc95xx_read_reg(dev, E2P_CMD, &val);
203 		if (!(val & E2P_CMD_BUSY_) || (val & E2P_CMD_TIMEOUT_))
204 			break;
205 		udelay(40);
206 	} while (!time_after(jiffies, start_time + HZ));
207 
208 	if (val & (E2P_CMD_TIMEOUT_ | E2P_CMD_BUSY_)) {
209 		netdev_warn(dev->net, "EEPROM read operation timeout\n");
210 		return -EIO;
211 	}
212 
213 	return 0;
214 }
215 
216 static int smsc95xx_eeprom_confirm_not_busy(struct usbnet *dev)
217 {
218 	unsigned long start_time = jiffies;
219 	u32 val;
220 
221 	do {
222 		smsc95xx_read_reg(dev, E2P_CMD, &val);
223 
224 		if (!(val & E2P_CMD_BUSY_))
225 			return 0;
226 
227 		udelay(40);
228 	} while (!time_after(jiffies, start_time + HZ));
229 
230 	netdev_warn(dev->net, "EEPROM is busy\n");
231 	return -EIO;
232 }
233 
234 static int smsc95xx_read_eeprom(struct usbnet *dev, u32 offset, u32 length,
235 				u8 *data)
236 {
237 	u32 val;
238 	int i, ret;
239 
240 	BUG_ON(!dev);
241 	BUG_ON(!data);
242 
243 	ret = smsc95xx_eeprom_confirm_not_busy(dev);
244 	if (ret)
245 		return ret;
246 
247 	for (i = 0; i < length; i++) {
248 		val = E2P_CMD_BUSY_ | E2P_CMD_READ_ | (offset & E2P_CMD_ADDR_);
249 		smsc95xx_write_reg(dev, E2P_CMD, val);
250 
251 		ret = smsc95xx_wait_eeprom(dev);
252 		if (ret < 0)
253 			return ret;
254 
255 		smsc95xx_read_reg(dev, E2P_DATA, &val);
256 
257 		data[i] = val & 0xFF;
258 		offset++;
259 	}
260 
261 	return 0;
262 }
263 
264 static int smsc95xx_write_eeprom(struct usbnet *dev, u32 offset, u32 length,
265 				 u8 *data)
266 {
267 	u32 val;
268 	int i, ret;
269 
270 	BUG_ON(!dev);
271 	BUG_ON(!data);
272 
273 	ret = smsc95xx_eeprom_confirm_not_busy(dev);
274 	if (ret)
275 		return ret;
276 
277 	/* Issue write/erase enable command */
278 	val = E2P_CMD_BUSY_ | E2P_CMD_EWEN_;
279 	smsc95xx_write_reg(dev, E2P_CMD, val);
280 
281 	ret = smsc95xx_wait_eeprom(dev);
282 	if (ret < 0)
283 		return ret;
284 
285 	for (i = 0; i < length; i++) {
286 
287 		/* Fill data register */
288 		val = data[i];
289 		smsc95xx_write_reg(dev, E2P_DATA, val);
290 
291 		/* Send "write" command */
292 		val = E2P_CMD_BUSY_ | E2P_CMD_WRITE_ | (offset & E2P_CMD_ADDR_);
293 		smsc95xx_write_reg(dev, E2P_CMD, val);
294 
295 		ret = smsc95xx_wait_eeprom(dev);
296 		if (ret < 0)
297 			return ret;
298 
299 		offset++;
300 	}
301 
302 	return 0;
303 }
304 
305 static void smsc95xx_async_cmd_callback(struct urb *urb)
306 {
307 	struct usb_context *usb_context = urb->context;
308 	struct usbnet *dev = usb_context->dev;
309 	int status = urb->status;
310 
311 	if (status < 0)
312 		netdev_warn(dev->net, "async callback failed with %d\n", status);
313 
314 	kfree(usb_context);
315 	usb_free_urb(urb);
316 }
317 
318 static int smsc95xx_write_reg_async(struct usbnet *dev, u16 index, u32 *data)
319 {
320 	struct usb_context *usb_context;
321 	int status;
322 	struct urb *urb;
323 	const u16 size = 4;
324 
325 	urb = usb_alloc_urb(0, GFP_ATOMIC);
326 	if (!urb) {
327 		netdev_warn(dev->net, "Error allocating URB\n");
328 		return -ENOMEM;
329 	}
330 
331 	usb_context = kmalloc(sizeof(struct usb_context), GFP_ATOMIC);
332 	if (usb_context == NULL) {
333 		netdev_warn(dev->net, "Error allocating control msg\n");
334 		usb_free_urb(urb);
335 		return -ENOMEM;
336 	}
337 
338 	usb_context->req.bRequestType =
339 		USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE;
340 	usb_context->req.bRequest = USB_VENDOR_REQUEST_WRITE_REGISTER;
341 	usb_context->req.wValue = 00;
342 	usb_context->req.wIndex = cpu_to_le16(index);
343 	usb_context->req.wLength = cpu_to_le16(size);
344 
345 	usb_fill_control_urb(urb, dev->udev, usb_sndctrlpipe(dev->udev, 0),
346 		(void *)&usb_context->req, data, size,
347 		smsc95xx_async_cmd_callback,
348 		(void *)usb_context);
349 
350 	status = usb_submit_urb(urb, GFP_ATOMIC);
351 	if (status < 0) {
352 		netdev_warn(dev->net, "Error submitting control msg, sts=%d\n",
353 			    status);
354 		kfree(usb_context);
355 		usb_free_urb(urb);
356 	}
357 
358 	return status;
359 }
360 
361 /* returns hash bit number for given MAC address
362  * example:
363  * 01 00 5E 00 00 01 -> returns bit number 31 */
364 static unsigned int smsc95xx_hash(char addr[ETH_ALEN])
365 {
366 	return (ether_crc(ETH_ALEN, addr) >> 26) & 0x3f;
367 }
368 
369 static void smsc95xx_set_multicast(struct net_device *netdev)
370 {
371 	struct usbnet *dev = netdev_priv(netdev);
372 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
373 	u32 hash_hi = 0;
374 	u32 hash_lo = 0;
375 	unsigned long flags;
376 
377 	spin_lock_irqsave(&pdata->mac_cr_lock, flags);
378 
379 	if (dev->net->flags & IFF_PROMISC) {
380 		netif_dbg(dev, drv, dev->net, "promiscuous mode enabled\n");
381 		pdata->mac_cr |= MAC_CR_PRMS_;
382 		pdata->mac_cr &= ~(MAC_CR_MCPAS_ | MAC_CR_HPFILT_);
383 	} else if (dev->net->flags & IFF_ALLMULTI) {
384 		netif_dbg(dev, drv, dev->net, "receive all multicast enabled\n");
385 		pdata->mac_cr |= MAC_CR_MCPAS_;
386 		pdata->mac_cr &= ~(MAC_CR_PRMS_ | MAC_CR_HPFILT_);
387 	} else if (!netdev_mc_empty(dev->net)) {
388 		struct netdev_hw_addr *ha;
389 
390 		pdata->mac_cr |= MAC_CR_HPFILT_;
391 		pdata->mac_cr &= ~(MAC_CR_PRMS_ | MAC_CR_MCPAS_);
392 
393 		netdev_for_each_mc_addr(ha, netdev) {
394 			u32 bitnum = smsc95xx_hash(ha->addr);
395 			u32 mask = 0x01 << (bitnum & 0x1F);
396 			if (bitnum & 0x20)
397 				hash_hi |= mask;
398 			else
399 				hash_lo |= mask;
400 		}
401 
402 		netif_dbg(dev, drv, dev->net, "HASHH=0x%08X, HASHL=0x%08X\n",
403 				   hash_hi, hash_lo);
404 	} else {
405 		netif_dbg(dev, drv, dev->net, "receive own packets only\n");
406 		pdata->mac_cr &=
407 			~(MAC_CR_PRMS_ | MAC_CR_MCPAS_ | MAC_CR_HPFILT_);
408 	}
409 
410 	spin_unlock_irqrestore(&pdata->mac_cr_lock, flags);
411 
412 	/* Initiate async writes, as we can't wait for completion here */
413 	smsc95xx_write_reg_async(dev, HASHH, &hash_hi);
414 	smsc95xx_write_reg_async(dev, HASHL, &hash_lo);
415 	smsc95xx_write_reg_async(dev, MAC_CR, &pdata->mac_cr);
416 }
417 
418 static void smsc95xx_phy_update_flowcontrol(struct usbnet *dev, u8 duplex,
419 					    u16 lcladv, u16 rmtadv)
420 {
421 	u32 flow, afc_cfg = 0;
422 
423 	int ret = smsc95xx_read_reg(dev, AFC_CFG, &afc_cfg);
424 	if (ret < 0) {
425 		netdev_warn(dev->net, "error reading AFC_CFG\n");
426 		return;
427 	}
428 
429 	if (duplex == DUPLEX_FULL) {
430 		u8 cap = mii_resolve_flowctrl_fdx(lcladv, rmtadv);
431 
432 		if (cap & FLOW_CTRL_RX)
433 			flow = 0xFFFF0002;
434 		else
435 			flow = 0;
436 
437 		if (cap & FLOW_CTRL_TX)
438 			afc_cfg |= 0xF;
439 		else
440 			afc_cfg &= ~0xF;
441 
442 		netif_dbg(dev, link, dev->net, "rx pause %s, tx pause %s\n",
443 				   cap & FLOW_CTRL_RX ? "enabled" : "disabled",
444 				   cap & FLOW_CTRL_TX ? "enabled" : "disabled");
445 	} else {
446 		netif_dbg(dev, link, dev->net, "half duplex\n");
447 		flow = 0;
448 		afc_cfg |= 0xF;
449 	}
450 
451 	smsc95xx_write_reg(dev, FLOW, flow);
452 	smsc95xx_write_reg(dev,	AFC_CFG, afc_cfg);
453 }
454 
455 static int smsc95xx_link_reset(struct usbnet *dev)
456 {
457 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
458 	struct mii_if_info *mii = &dev->mii;
459 	struct ethtool_cmd ecmd;
460 	unsigned long flags;
461 	u16 lcladv, rmtadv;
462 	u32 intdata;
463 
464 	/* clear interrupt status */
465 	smsc95xx_mdio_read(dev->net, mii->phy_id, PHY_INT_SRC);
466 	intdata = 0xFFFFFFFF;
467 	smsc95xx_write_reg(dev, INT_STS, intdata);
468 
469 	mii_check_media(mii, 1, 1);
470 	mii_ethtool_gset(&dev->mii, &ecmd);
471 	lcladv = smsc95xx_mdio_read(dev->net, mii->phy_id, MII_ADVERTISE);
472 	rmtadv = smsc95xx_mdio_read(dev->net, mii->phy_id, MII_LPA);
473 
474 	netif_dbg(dev, link, dev->net, "speed: %d duplex: %d lcladv: %04x rmtadv: %04x\n",
475 		  ecmd.speed, ecmd.duplex, lcladv, rmtadv);
476 
477 	spin_lock_irqsave(&pdata->mac_cr_lock, flags);
478 	if (ecmd.duplex != DUPLEX_FULL) {
479 		pdata->mac_cr &= ~MAC_CR_FDPX_;
480 		pdata->mac_cr |= MAC_CR_RCVOWN_;
481 	} else {
482 		pdata->mac_cr &= ~MAC_CR_RCVOWN_;
483 		pdata->mac_cr |= MAC_CR_FDPX_;
484 	}
485 	spin_unlock_irqrestore(&pdata->mac_cr_lock, flags);
486 
487 	smsc95xx_write_reg(dev, MAC_CR, pdata->mac_cr);
488 
489 	smsc95xx_phy_update_flowcontrol(dev, ecmd.duplex, lcladv, rmtadv);
490 
491 	return 0;
492 }
493 
494 static void smsc95xx_status(struct usbnet *dev, struct urb *urb)
495 {
496 	u32 intdata;
497 
498 	if (urb->actual_length != 4) {
499 		netdev_warn(dev->net, "unexpected urb length %d\n",
500 			    urb->actual_length);
501 		return;
502 	}
503 
504 	memcpy(&intdata, urb->transfer_buffer, 4);
505 	le32_to_cpus(&intdata);
506 
507 	netif_dbg(dev, link, dev->net, "intdata: 0x%08X\n", intdata);
508 
509 	if (intdata & INT_ENP_PHY_INT_)
510 		usbnet_defer_kevent(dev, EVENT_LINK_RESET);
511 	else
512 		netdev_warn(dev->net, "unexpected interrupt, intdata=0x%08X\n",
513 			    intdata);
514 }
515 
516 /* Enable or disable Tx & Rx checksum offload engines */
517 static int smsc95xx_set_csums(struct usbnet *dev)
518 {
519 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
520 	u32 read_buf;
521 	int ret = smsc95xx_read_reg(dev, COE_CR, &read_buf);
522 	if (ret < 0) {
523 		netdev_warn(dev->net, "Failed to read COE_CR: %d\n", ret);
524 		return ret;
525 	}
526 
527 	if (pdata->use_tx_csum)
528 		read_buf |= Tx_COE_EN_;
529 	else
530 		read_buf &= ~Tx_COE_EN_;
531 
532 	if (pdata->use_rx_csum)
533 		read_buf |= Rx_COE_EN_;
534 	else
535 		read_buf &= ~Rx_COE_EN_;
536 
537 	ret = smsc95xx_write_reg(dev, COE_CR, read_buf);
538 	if (ret < 0) {
539 		netdev_warn(dev->net, "Failed to write COE_CR: %d\n", ret);
540 		return ret;
541 	}
542 
543 	netif_dbg(dev, hw, dev->net, "COE_CR = 0x%08x\n", read_buf);
544 	return 0;
545 }
546 
547 static int smsc95xx_ethtool_get_eeprom_len(struct net_device *net)
548 {
549 	return MAX_EEPROM_SIZE;
550 }
551 
552 static int smsc95xx_ethtool_get_eeprom(struct net_device *netdev,
553 				       struct ethtool_eeprom *ee, u8 *data)
554 {
555 	struct usbnet *dev = netdev_priv(netdev);
556 
557 	ee->magic = LAN95XX_EEPROM_MAGIC;
558 
559 	return smsc95xx_read_eeprom(dev, ee->offset, ee->len, data);
560 }
561 
562 static int smsc95xx_ethtool_set_eeprom(struct net_device *netdev,
563 				       struct ethtool_eeprom *ee, u8 *data)
564 {
565 	struct usbnet *dev = netdev_priv(netdev);
566 
567 	if (ee->magic != LAN95XX_EEPROM_MAGIC) {
568 		netdev_warn(dev->net, "EEPROM: magic value mismatch, magic = 0x%x\n",
569 			    ee->magic);
570 		return -EINVAL;
571 	}
572 
573 	return smsc95xx_write_eeprom(dev, ee->offset, ee->len, data);
574 }
575 
576 static u32 smsc95xx_ethtool_get_rx_csum(struct net_device *netdev)
577 {
578 	struct usbnet *dev = netdev_priv(netdev);
579 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
580 
581 	return pdata->use_rx_csum;
582 }
583 
584 static int smsc95xx_ethtool_set_rx_csum(struct net_device *netdev, u32 val)
585 {
586 	struct usbnet *dev = netdev_priv(netdev);
587 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
588 
589 	pdata->use_rx_csum = !!val;
590 
591 	return smsc95xx_set_csums(dev);
592 }
593 
594 static u32 smsc95xx_ethtool_get_tx_csum(struct net_device *netdev)
595 {
596 	struct usbnet *dev = netdev_priv(netdev);
597 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
598 
599 	return pdata->use_tx_csum;
600 }
601 
602 static int smsc95xx_ethtool_set_tx_csum(struct net_device *netdev, u32 val)
603 {
604 	struct usbnet *dev = netdev_priv(netdev);
605 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
606 
607 	pdata->use_tx_csum = !!val;
608 
609 	ethtool_op_set_tx_hw_csum(netdev, pdata->use_tx_csum);
610 	return smsc95xx_set_csums(dev);
611 }
612 
613 static const struct ethtool_ops smsc95xx_ethtool_ops = {
614 	.get_link	= usbnet_get_link,
615 	.nway_reset	= usbnet_nway_reset,
616 	.get_drvinfo	= usbnet_get_drvinfo,
617 	.get_msglevel	= usbnet_get_msglevel,
618 	.set_msglevel	= usbnet_set_msglevel,
619 	.get_settings	= usbnet_get_settings,
620 	.set_settings	= usbnet_set_settings,
621 	.get_eeprom_len	= smsc95xx_ethtool_get_eeprom_len,
622 	.get_eeprom	= smsc95xx_ethtool_get_eeprom,
623 	.set_eeprom	= smsc95xx_ethtool_set_eeprom,
624 	.get_tx_csum	= smsc95xx_ethtool_get_tx_csum,
625 	.set_tx_csum	= smsc95xx_ethtool_set_tx_csum,
626 	.get_rx_csum	= smsc95xx_ethtool_get_rx_csum,
627 	.set_rx_csum	= smsc95xx_ethtool_set_rx_csum,
628 };
629 
630 static int smsc95xx_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
631 {
632 	struct usbnet *dev = netdev_priv(netdev);
633 
634 	if (!netif_running(netdev))
635 		return -EINVAL;
636 
637 	return generic_mii_ioctl(&dev->mii, if_mii(rq), cmd, NULL);
638 }
639 
640 static void smsc95xx_init_mac_address(struct usbnet *dev)
641 {
642 	/* try reading mac address from EEPROM */
643 	if (smsc95xx_read_eeprom(dev, EEPROM_MAC_OFFSET, ETH_ALEN,
644 			dev->net->dev_addr) == 0) {
645 		if (is_valid_ether_addr(dev->net->dev_addr)) {
646 			/* eeprom values are valid so use them */
647 			netif_dbg(dev, ifup, dev->net, "MAC address read from EEPROM\n");
648 			return;
649 		}
650 	}
651 
652 	/* no eeprom, or eeprom values are invalid. generate random MAC */
653 	random_ether_addr(dev->net->dev_addr);
654 	netif_dbg(dev, ifup, dev->net, "MAC address set to random_ether_addr\n");
655 }
656 
657 static int smsc95xx_set_mac_address(struct usbnet *dev)
658 {
659 	u32 addr_lo = dev->net->dev_addr[0] | dev->net->dev_addr[1] << 8 |
660 		dev->net->dev_addr[2] << 16 | dev->net->dev_addr[3] << 24;
661 	u32 addr_hi = dev->net->dev_addr[4] | dev->net->dev_addr[5] << 8;
662 	int ret;
663 
664 	ret = smsc95xx_write_reg(dev, ADDRL, addr_lo);
665 	if (ret < 0) {
666 		netdev_warn(dev->net, "Failed to write ADDRL: %d\n", ret);
667 		return ret;
668 	}
669 
670 	ret = smsc95xx_write_reg(dev, ADDRH, addr_hi);
671 	if (ret < 0) {
672 		netdev_warn(dev->net, "Failed to write ADDRH: %d\n", ret);
673 		return ret;
674 	}
675 
676 	return 0;
677 }
678 
679 /* starts the TX path */
680 static void smsc95xx_start_tx_path(struct usbnet *dev)
681 {
682 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
683 	unsigned long flags;
684 	u32 reg_val;
685 
686 	/* Enable Tx at MAC */
687 	spin_lock_irqsave(&pdata->mac_cr_lock, flags);
688 	pdata->mac_cr |= MAC_CR_TXEN_;
689 	spin_unlock_irqrestore(&pdata->mac_cr_lock, flags);
690 
691 	smsc95xx_write_reg(dev, MAC_CR, pdata->mac_cr);
692 
693 	/* Enable Tx at SCSRs */
694 	reg_val = TX_CFG_ON_;
695 	smsc95xx_write_reg(dev, TX_CFG, reg_val);
696 }
697 
698 /* Starts the Receive path */
699 static void smsc95xx_start_rx_path(struct usbnet *dev)
700 {
701 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
702 	unsigned long flags;
703 
704 	spin_lock_irqsave(&pdata->mac_cr_lock, flags);
705 	pdata->mac_cr |= MAC_CR_RXEN_;
706 	spin_unlock_irqrestore(&pdata->mac_cr_lock, flags);
707 
708 	smsc95xx_write_reg(dev, MAC_CR, pdata->mac_cr);
709 }
710 
711 static int smsc95xx_phy_initialize(struct usbnet *dev)
712 {
713 	int bmcr, timeout = 0;
714 
715 	/* Initialize MII structure */
716 	dev->mii.dev = dev->net;
717 	dev->mii.mdio_read = smsc95xx_mdio_read;
718 	dev->mii.mdio_write = smsc95xx_mdio_write;
719 	dev->mii.phy_id_mask = 0x1f;
720 	dev->mii.reg_num_mask = 0x1f;
721 	dev->mii.phy_id = SMSC95XX_INTERNAL_PHY_ID;
722 
723 	/* reset phy and wait for reset to complete */
724 	smsc95xx_mdio_write(dev->net, dev->mii.phy_id, MII_BMCR, BMCR_RESET);
725 
726 	do {
727 		msleep(10);
728 		bmcr = smsc95xx_mdio_read(dev->net, dev->mii.phy_id, MII_BMCR);
729 		timeout++;
730 	} while ((bmcr & MII_BMCR) && (timeout < 100));
731 
732 	if (timeout >= 100) {
733 		netdev_warn(dev->net, "timeout on PHY Reset");
734 		return -EIO;
735 	}
736 
737 	smsc95xx_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE,
738 		ADVERTISE_ALL | ADVERTISE_CSMA | ADVERTISE_PAUSE_CAP |
739 		ADVERTISE_PAUSE_ASYM);
740 
741 	/* read to clear */
742 	smsc95xx_mdio_read(dev->net, dev->mii.phy_id, PHY_INT_SRC);
743 
744 	smsc95xx_mdio_write(dev->net, dev->mii.phy_id, PHY_INT_MASK,
745 		PHY_INT_MASK_DEFAULT_);
746 	mii_nway_restart(&dev->mii);
747 
748 	netif_dbg(dev, ifup, dev->net, "phy initialised successfully\n");
749 	return 0;
750 }
751 
752 static int smsc95xx_reset(struct usbnet *dev)
753 {
754 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
755 	struct net_device *netdev = dev->net;
756 	u32 read_buf, write_buf, burst_cap;
757 	int ret = 0, timeout;
758 
759 	netif_dbg(dev, ifup, dev->net, "entering smsc95xx_reset\n");
760 
761 	write_buf = HW_CFG_LRST_;
762 	ret = smsc95xx_write_reg(dev, HW_CFG, write_buf);
763 	if (ret < 0) {
764 		netdev_warn(dev->net, "Failed to write HW_CFG_LRST_ bit in HW_CFG register, ret = %d\n",
765 			    ret);
766 		return ret;
767 	}
768 
769 	timeout = 0;
770 	do {
771 		ret = smsc95xx_read_reg(dev, HW_CFG, &read_buf);
772 		if (ret < 0) {
773 			netdev_warn(dev->net, "Failed to read HW_CFG: %d\n", ret);
774 			return ret;
775 		}
776 		msleep(10);
777 		timeout++;
778 	} while ((read_buf & HW_CFG_LRST_) && (timeout < 100));
779 
780 	if (timeout >= 100) {
781 		netdev_warn(dev->net, "timeout waiting for completion of Lite Reset\n");
782 		return ret;
783 	}
784 
785 	write_buf = PM_CTL_PHY_RST_;
786 	ret = smsc95xx_write_reg(dev, PM_CTRL, write_buf);
787 	if (ret < 0) {
788 		netdev_warn(dev->net, "Failed to write PM_CTRL: %d\n", ret);
789 		return ret;
790 	}
791 
792 	timeout = 0;
793 	do {
794 		ret = smsc95xx_read_reg(dev, PM_CTRL, &read_buf);
795 		if (ret < 0) {
796 			netdev_warn(dev->net, "Failed to read PM_CTRL: %d\n", ret);
797 			return ret;
798 		}
799 		msleep(10);
800 		timeout++;
801 	} while ((read_buf & PM_CTL_PHY_RST_) && (timeout < 100));
802 
803 	if (timeout >= 100) {
804 		netdev_warn(dev->net, "timeout waiting for PHY Reset\n");
805 		return ret;
806 	}
807 
808 	ret = smsc95xx_set_mac_address(dev);
809 	if (ret < 0)
810 		return ret;
811 
812 	netif_dbg(dev, ifup, dev->net,
813 		  "MAC Address: %pM\n", dev->net->dev_addr);
814 
815 	ret = smsc95xx_read_reg(dev, HW_CFG, &read_buf);
816 	if (ret < 0) {
817 		netdev_warn(dev->net, "Failed to read HW_CFG: %d\n", ret);
818 		return ret;
819 	}
820 
821 	netif_dbg(dev, ifup, dev->net,
822 		  "Read Value from HW_CFG : 0x%08x\n", read_buf);
823 
824 	read_buf |= HW_CFG_BIR_;
825 
826 	ret = smsc95xx_write_reg(dev, HW_CFG, read_buf);
827 	if (ret < 0) {
828 		netdev_warn(dev->net, "Failed to write HW_CFG_BIR_ bit in HW_CFG register, ret = %d\n",
829 			    ret);
830 		return ret;
831 	}
832 
833 	ret = smsc95xx_read_reg(dev, HW_CFG, &read_buf);
834 	if (ret < 0) {
835 		netdev_warn(dev->net, "Failed to read HW_CFG: %d\n", ret);
836 		return ret;
837 	}
838 	netif_dbg(dev, ifup, dev->net,
839 		  "Read Value from HW_CFG after writing HW_CFG_BIR_: 0x%08x\n",
840 		  read_buf);
841 
842 	if (!turbo_mode) {
843 		burst_cap = 0;
844 		dev->rx_urb_size = MAX_SINGLE_PACKET_SIZE;
845 	} else if (dev->udev->speed == USB_SPEED_HIGH) {
846 		burst_cap = DEFAULT_HS_BURST_CAP_SIZE / HS_USB_PKT_SIZE;
847 		dev->rx_urb_size = DEFAULT_HS_BURST_CAP_SIZE;
848 	} else {
849 		burst_cap = DEFAULT_FS_BURST_CAP_SIZE / FS_USB_PKT_SIZE;
850 		dev->rx_urb_size = DEFAULT_FS_BURST_CAP_SIZE;
851 	}
852 
853 	netif_dbg(dev, ifup, dev->net,
854 		  "rx_urb_size=%ld\n", (ulong)dev->rx_urb_size);
855 
856 	ret = smsc95xx_write_reg(dev, BURST_CAP, burst_cap);
857 	if (ret < 0) {
858 		netdev_warn(dev->net, "Failed to write BURST_CAP: %d\n", ret);
859 		return ret;
860 	}
861 
862 	ret = smsc95xx_read_reg(dev, BURST_CAP, &read_buf);
863 	if (ret < 0) {
864 		netdev_warn(dev->net, "Failed to read BURST_CAP: %d\n", ret);
865 		return ret;
866 	}
867 	netif_dbg(dev, ifup, dev->net,
868 		  "Read Value from BURST_CAP after writing: 0x%08x\n",
869 		  read_buf);
870 
871 	read_buf = DEFAULT_BULK_IN_DELAY;
872 	ret = smsc95xx_write_reg(dev, BULK_IN_DLY, read_buf);
873 	if (ret < 0) {
874 		netdev_warn(dev->net, "ret = %d\n", ret);
875 		return ret;
876 	}
877 
878 	ret = smsc95xx_read_reg(dev, BULK_IN_DLY, &read_buf);
879 	if (ret < 0) {
880 		netdev_warn(dev->net, "Failed to read BULK_IN_DLY: %d\n", ret);
881 		return ret;
882 	}
883 	netif_dbg(dev, ifup, dev->net,
884 		  "Read Value from BULK_IN_DLY after writing: 0x%08x\n",
885 		  read_buf);
886 
887 	ret = smsc95xx_read_reg(dev, HW_CFG, &read_buf);
888 	if (ret < 0) {
889 		netdev_warn(dev->net, "Failed to read HW_CFG: %d\n", ret);
890 		return ret;
891 	}
892 	netif_dbg(dev, ifup, dev->net,
893 		  "Read Value from HW_CFG: 0x%08x\n", read_buf);
894 
895 	if (turbo_mode)
896 		read_buf |= (HW_CFG_MEF_ | HW_CFG_BCE_);
897 
898 	read_buf &= ~HW_CFG_RXDOFF_;
899 
900 	/* set Rx data offset=2, Make IP header aligns on word boundary. */
901 	read_buf |= NET_IP_ALIGN << 9;
902 
903 	ret = smsc95xx_write_reg(dev, HW_CFG, read_buf);
904 	if (ret < 0) {
905 		netdev_warn(dev->net, "Failed to write HW_CFG register, ret=%d\n",
906 			    ret);
907 		return ret;
908 	}
909 
910 	ret = smsc95xx_read_reg(dev, HW_CFG, &read_buf);
911 	if (ret < 0) {
912 		netdev_warn(dev->net, "Failed to read HW_CFG: %d\n", ret);
913 		return ret;
914 	}
915 	netif_dbg(dev, ifup, dev->net,
916 		  "Read Value from HW_CFG after writing: 0x%08x\n", read_buf);
917 
918 	write_buf = 0xFFFFFFFF;
919 	ret = smsc95xx_write_reg(dev, INT_STS, write_buf);
920 	if (ret < 0) {
921 		netdev_warn(dev->net, "Failed to write INT_STS register, ret=%d\n",
922 			    ret);
923 		return ret;
924 	}
925 
926 	ret = smsc95xx_read_reg(dev, ID_REV, &read_buf);
927 	if (ret < 0) {
928 		netdev_warn(dev->net, "Failed to read ID_REV: %d\n", ret);
929 		return ret;
930 	}
931 	netif_dbg(dev, ifup, dev->net, "ID_REV = 0x%08x\n", read_buf);
932 
933 	/* Configure GPIO pins as LED outputs */
934 	write_buf = LED_GPIO_CFG_SPD_LED | LED_GPIO_CFG_LNK_LED |
935 		LED_GPIO_CFG_FDX_LED;
936 	ret = smsc95xx_write_reg(dev, LED_GPIO_CFG, write_buf);
937 	if (ret < 0) {
938 		netdev_warn(dev->net, "Failed to write LED_GPIO_CFG register, ret=%d\n",
939 			    ret);
940 		return ret;
941 	}
942 
943 	/* Init Tx */
944 	write_buf = 0;
945 	ret = smsc95xx_write_reg(dev, FLOW, write_buf);
946 	if (ret < 0) {
947 		netdev_warn(dev->net, "Failed to write FLOW: %d\n", ret);
948 		return ret;
949 	}
950 
951 	read_buf = AFC_CFG_DEFAULT;
952 	ret = smsc95xx_write_reg(dev, AFC_CFG, read_buf);
953 	if (ret < 0) {
954 		netdev_warn(dev->net, "Failed to write AFC_CFG: %d\n", ret);
955 		return ret;
956 	}
957 
958 	/* Don't need mac_cr_lock during initialisation */
959 	ret = smsc95xx_read_reg(dev, MAC_CR, &pdata->mac_cr);
960 	if (ret < 0) {
961 		netdev_warn(dev->net, "Failed to read MAC_CR: %d\n", ret);
962 		return ret;
963 	}
964 
965 	/* Init Rx */
966 	/* Set Vlan */
967 	write_buf = (u32)ETH_P_8021Q;
968 	ret = smsc95xx_write_reg(dev, VLAN1, write_buf);
969 	if (ret < 0) {
970 		netdev_warn(dev->net, "Failed to write VAN1: %d\n", ret);
971 		return ret;
972 	}
973 
974 	/* Enable or disable checksum offload engines */
975 	ethtool_op_set_tx_hw_csum(netdev, pdata->use_tx_csum);
976 	ret = smsc95xx_set_csums(dev);
977 	if (ret < 0) {
978 		netdev_warn(dev->net, "Failed to set csum offload: %d\n", ret);
979 		return ret;
980 	}
981 
982 	smsc95xx_set_multicast(dev->net);
983 
984 	if (smsc95xx_phy_initialize(dev) < 0)
985 		return -EIO;
986 
987 	ret = smsc95xx_read_reg(dev, INT_EP_CTL, &read_buf);
988 	if (ret < 0) {
989 		netdev_warn(dev->net, "Failed to read INT_EP_CTL: %d\n", ret);
990 		return ret;
991 	}
992 
993 	/* enable PHY interrupts */
994 	read_buf |= INT_EP_CTL_PHY_INT_;
995 
996 	ret = smsc95xx_write_reg(dev, INT_EP_CTL, read_buf);
997 	if (ret < 0) {
998 		netdev_warn(dev->net, "Failed to write INT_EP_CTL: %d\n", ret);
999 		return ret;
1000 	}
1001 
1002 	smsc95xx_start_tx_path(dev);
1003 	smsc95xx_start_rx_path(dev);
1004 
1005 	netif_dbg(dev, ifup, dev->net, "smsc95xx_reset, return 0\n");
1006 	return 0;
1007 }
1008 
1009 static const struct net_device_ops smsc95xx_netdev_ops = {
1010 	.ndo_open		= usbnet_open,
1011 	.ndo_stop		= usbnet_stop,
1012 	.ndo_start_xmit		= usbnet_start_xmit,
1013 	.ndo_tx_timeout		= usbnet_tx_timeout,
1014 	.ndo_change_mtu		= usbnet_change_mtu,
1015 	.ndo_set_mac_address 	= eth_mac_addr,
1016 	.ndo_validate_addr	= eth_validate_addr,
1017 	.ndo_do_ioctl 		= smsc95xx_ioctl,
1018 	.ndo_set_multicast_list = smsc95xx_set_multicast,
1019 };
1020 
1021 static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf)
1022 {
1023 	struct smsc95xx_priv *pdata = NULL;
1024 	int ret;
1025 
1026 	printk(KERN_INFO SMSC_CHIPNAME " v" SMSC_DRIVER_VERSION "\n");
1027 
1028 	ret = usbnet_get_endpoints(dev, intf);
1029 	if (ret < 0) {
1030 		netdev_warn(dev->net, "usbnet_get_endpoints failed: %d\n", ret);
1031 		return ret;
1032 	}
1033 
1034 	dev->data[0] = (unsigned long)kzalloc(sizeof(struct smsc95xx_priv),
1035 		GFP_KERNEL);
1036 
1037 	pdata = (struct smsc95xx_priv *)(dev->data[0]);
1038 	if (!pdata) {
1039 		netdev_warn(dev->net, "Unable to allocate struct smsc95xx_priv\n");
1040 		return -ENOMEM;
1041 	}
1042 
1043 	spin_lock_init(&pdata->mac_cr_lock);
1044 
1045 	pdata->use_tx_csum = DEFAULT_TX_CSUM_ENABLE;
1046 	pdata->use_rx_csum = DEFAULT_RX_CSUM_ENABLE;
1047 
1048 	smsc95xx_init_mac_address(dev);
1049 
1050 	/* Init all registers */
1051 	ret = smsc95xx_reset(dev);
1052 
1053 	dev->net->netdev_ops = &smsc95xx_netdev_ops;
1054 	dev->net->ethtool_ops = &smsc95xx_ethtool_ops;
1055 	dev->net->flags |= IFF_MULTICAST;
1056 	dev->net->hard_header_len += SMSC95XX_TX_OVERHEAD;
1057 	return 0;
1058 }
1059 
1060 static void smsc95xx_unbind(struct usbnet *dev, struct usb_interface *intf)
1061 {
1062 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
1063 	if (pdata) {
1064 		netif_dbg(dev, ifdown, dev->net, "free pdata\n");
1065 		kfree(pdata);
1066 		pdata = NULL;
1067 		dev->data[0] = 0;
1068 	}
1069 }
1070 
1071 static void smsc95xx_rx_csum_offload(struct sk_buff *skb)
1072 {
1073 	skb->csum = *(u16 *)(skb_tail_pointer(skb) - 2);
1074 	skb->ip_summed = CHECKSUM_COMPLETE;
1075 	skb_trim(skb, skb->len - 2);
1076 }
1077 
1078 static int smsc95xx_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
1079 {
1080 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
1081 
1082 	while (skb->len > 0) {
1083 		u32 header, align_count;
1084 		struct sk_buff *ax_skb;
1085 		unsigned char *packet;
1086 		u16 size;
1087 
1088 		memcpy(&header, skb->data, sizeof(header));
1089 		le32_to_cpus(&header);
1090 		skb_pull(skb, 4 + NET_IP_ALIGN);
1091 		packet = skb->data;
1092 
1093 		/* get the packet length */
1094 		size = (u16)((header & RX_STS_FL_) >> 16);
1095 		align_count = (4 - ((size + NET_IP_ALIGN) % 4)) % 4;
1096 
1097 		if (unlikely(header & RX_STS_ES_)) {
1098 			netif_dbg(dev, rx_err, dev->net,
1099 				  "Error header=0x%08x\n", header);
1100 			dev->net->stats.rx_errors++;
1101 			dev->net->stats.rx_dropped++;
1102 
1103 			if (header & RX_STS_CRC_) {
1104 				dev->net->stats.rx_crc_errors++;
1105 			} else {
1106 				if (header & (RX_STS_TL_ | RX_STS_RF_))
1107 					dev->net->stats.rx_frame_errors++;
1108 
1109 				if ((header & RX_STS_LE_) &&
1110 					(!(header & RX_STS_FT_)))
1111 					dev->net->stats.rx_length_errors++;
1112 			}
1113 		} else {
1114 			/* ETH_FRAME_LEN + 4(CRC) + 2(COE) + 4(Vlan) */
1115 			if (unlikely(size > (ETH_FRAME_LEN + 12))) {
1116 				netif_dbg(dev, rx_err, dev->net,
1117 					  "size err header=0x%08x\n", header);
1118 				return 0;
1119 			}
1120 
1121 			/* last frame in this batch */
1122 			if (skb->len == size) {
1123 				if (pdata->use_rx_csum)
1124 					smsc95xx_rx_csum_offload(skb);
1125 				skb_trim(skb, skb->len - 4); /* remove fcs */
1126 				skb->truesize = size + sizeof(struct sk_buff);
1127 
1128 				return 1;
1129 			}
1130 
1131 			ax_skb = skb_clone(skb, GFP_ATOMIC);
1132 			if (unlikely(!ax_skb)) {
1133 				netdev_warn(dev->net, "Error allocating skb\n");
1134 				return 0;
1135 			}
1136 
1137 			ax_skb->len = size;
1138 			ax_skb->data = packet;
1139 			skb_set_tail_pointer(ax_skb, size);
1140 
1141 			if (pdata->use_rx_csum)
1142 				smsc95xx_rx_csum_offload(ax_skb);
1143 			skb_trim(ax_skb, ax_skb->len - 4); /* remove fcs */
1144 			ax_skb->truesize = size + sizeof(struct sk_buff);
1145 
1146 			usbnet_skb_return(dev, ax_skb);
1147 		}
1148 
1149 		skb_pull(skb, size);
1150 
1151 		/* padding bytes before the next frame starts */
1152 		if (skb->len)
1153 			skb_pull(skb, align_count);
1154 	}
1155 
1156 	if (unlikely(skb->len < 0)) {
1157 		netdev_warn(dev->net, "invalid rx length<0 %d\n", skb->len);
1158 		return 0;
1159 	}
1160 
1161 	return 1;
1162 }
1163 
1164 static u32 smsc95xx_calc_csum_preamble(struct sk_buff *skb)
1165 {
1166 	int len = skb->data - skb->head;
1167 	u16 high_16 = (u16)(skb->csum_offset + skb->csum_start - len);
1168 	u16 low_16 = (u16)(skb->csum_start - len);
1169 	return (high_16 << 16) | low_16;
1170 }
1171 
1172 static struct sk_buff *smsc95xx_tx_fixup(struct usbnet *dev,
1173 					 struct sk_buff *skb, gfp_t flags)
1174 {
1175 	struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]);
1176 	bool csum = pdata->use_tx_csum && (skb->ip_summed == CHECKSUM_PARTIAL);
1177 	int overhead = csum ? SMSC95XX_TX_OVERHEAD_CSUM : SMSC95XX_TX_OVERHEAD;
1178 	u32 tx_cmd_a, tx_cmd_b;
1179 
1180 	/* We do not advertise SG, so skbs should be already linearized */
1181 	BUG_ON(skb_shinfo(skb)->nr_frags);
1182 
1183 	if (skb_headroom(skb) < overhead) {
1184 		struct sk_buff *skb2 = skb_copy_expand(skb,
1185 			overhead, 0, flags);
1186 		dev_kfree_skb_any(skb);
1187 		skb = skb2;
1188 		if (!skb)
1189 			return NULL;
1190 	}
1191 
1192 	if (csum) {
1193 		if (skb->len <= 45) {
1194 			/* workaround - hardware tx checksum does not work
1195 			 * properly with extremely small packets */
1196 			long csstart = skb->csum_start - skb_headroom(skb);
1197 			__wsum calc = csum_partial(skb->data + csstart,
1198 				skb->len - csstart, 0);
1199 			*((__sum16 *)(skb->data + csstart
1200 				+ skb->csum_offset)) = csum_fold(calc);
1201 
1202 			csum = false;
1203 		} else {
1204 			u32 csum_preamble = smsc95xx_calc_csum_preamble(skb);
1205 			skb_push(skb, 4);
1206 			memcpy(skb->data, &csum_preamble, 4);
1207 		}
1208 	}
1209 
1210 	skb_push(skb, 4);
1211 	tx_cmd_b = (u32)(skb->len - 4);
1212 	if (csum)
1213 		tx_cmd_b |= TX_CMD_B_CSUM_ENABLE;
1214 	cpu_to_le32s(&tx_cmd_b);
1215 	memcpy(skb->data, &tx_cmd_b, 4);
1216 
1217 	skb_push(skb, 4);
1218 	tx_cmd_a = (u32)(skb->len - 8) | TX_CMD_A_FIRST_SEG_ |
1219 		TX_CMD_A_LAST_SEG_;
1220 	cpu_to_le32s(&tx_cmd_a);
1221 	memcpy(skb->data, &tx_cmd_a, 4);
1222 
1223 	return skb;
1224 }
1225 
1226 static const struct driver_info smsc95xx_info = {
1227 	.description	= "smsc95xx USB 2.0 Ethernet",
1228 	.bind		= smsc95xx_bind,
1229 	.unbind		= smsc95xx_unbind,
1230 	.link_reset	= smsc95xx_link_reset,
1231 	.reset		= smsc95xx_reset,
1232 	.rx_fixup	= smsc95xx_rx_fixup,
1233 	.tx_fixup	= smsc95xx_tx_fixup,
1234 	.status		= smsc95xx_status,
1235 	.flags		= FLAG_ETHER | FLAG_SEND_ZLP,
1236 };
1237 
1238 static const struct usb_device_id products[] = {
1239 	{
1240 		/* SMSC9500 USB Ethernet Device */
1241 		USB_DEVICE(0x0424, 0x9500),
1242 		.driver_info = (unsigned long) &smsc95xx_info,
1243 	},
1244 	{
1245 		/* SMSC9505 USB Ethernet Device */
1246 		USB_DEVICE(0x0424, 0x9505),
1247 		.driver_info = (unsigned long) &smsc95xx_info,
1248 	},
1249 	{
1250 		/* SMSC9500A USB Ethernet Device */
1251 		USB_DEVICE(0x0424, 0x9E00),
1252 		.driver_info = (unsigned long) &smsc95xx_info,
1253 	},
1254 	{
1255 		/* SMSC9505A USB Ethernet Device */
1256 		USB_DEVICE(0x0424, 0x9E01),
1257 		.driver_info = (unsigned long) &smsc95xx_info,
1258 	},
1259 	{
1260 		/* SMSC9512/9514 USB Hub & Ethernet Device */
1261 		USB_DEVICE(0x0424, 0xec00),
1262 		.driver_info = (unsigned long) &smsc95xx_info,
1263 	},
1264 	{
1265 		/* SMSC9500 USB Ethernet Device (SAL10) */
1266 		USB_DEVICE(0x0424, 0x9900),
1267 		.driver_info = (unsigned long) &smsc95xx_info,
1268 	},
1269 	{
1270 		/* SMSC9505 USB Ethernet Device (SAL10) */
1271 		USB_DEVICE(0x0424, 0x9901),
1272 		.driver_info = (unsigned long) &smsc95xx_info,
1273 	},
1274 	{
1275 		/* SMSC9500A USB Ethernet Device (SAL10) */
1276 		USB_DEVICE(0x0424, 0x9902),
1277 		.driver_info = (unsigned long) &smsc95xx_info,
1278 	},
1279 	{
1280 		/* SMSC9505A USB Ethernet Device (SAL10) */
1281 		USB_DEVICE(0x0424, 0x9903),
1282 		.driver_info = (unsigned long) &smsc95xx_info,
1283 	},
1284 	{
1285 		/* SMSC9512/9514 USB Hub & Ethernet Device (SAL10) */
1286 		USB_DEVICE(0x0424, 0x9904),
1287 		.driver_info = (unsigned long) &smsc95xx_info,
1288 	},
1289 	{
1290 		/* SMSC9500A USB Ethernet Device (HAL) */
1291 		USB_DEVICE(0x0424, 0x9905),
1292 		.driver_info = (unsigned long) &smsc95xx_info,
1293 	},
1294 	{
1295 		/* SMSC9505A USB Ethernet Device (HAL) */
1296 		USB_DEVICE(0x0424, 0x9906),
1297 		.driver_info = (unsigned long) &smsc95xx_info,
1298 	},
1299 	{
1300 		/* SMSC9500 USB Ethernet Device (Alternate ID) */
1301 		USB_DEVICE(0x0424, 0x9907),
1302 		.driver_info = (unsigned long) &smsc95xx_info,
1303 	},
1304 	{
1305 		/* SMSC9500A USB Ethernet Device (Alternate ID) */
1306 		USB_DEVICE(0x0424, 0x9908),
1307 		.driver_info = (unsigned long) &smsc95xx_info,
1308 	},
1309 	{
1310 		/* SMSC9512/9514 USB Hub & Ethernet Device (Alternate ID) */
1311 		USB_DEVICE(0x0424, 0x9909),
1312 		.driver_info = (unsigned long) &smsc95xx_info,
1313 	},
1314 	{ },		/* END */
1315 };
1316 MODULE_DEVICE_TABLE(usb, products);
1317 
1318 static struct usb_driver smsc95xx_driver = {
1319 	.name		= "smsc95xx",
1320 	.id_table	= products,
1321 	.probe		= usbnet_probe,
1322 	.suspend	= usbnet_suspend,
1323 	.resume		= usbnet_resume,
1324 	.disconnect	= usbnet_disconnect,
1325 };
1326 
1327 static int __init smsc95xx_init(void)
1328 {
1329 	return usb_register(&smsc95xx_driver);
1330 }
1331 module_init(smsc95xx_init);
1332 
1333 static void __exit smsc95xx_exit(void)
1334 {
1335 	usb_deregister(&smsc95xx_driver);
1336 }
1337 module_exit(smsc95xx_exit);
1338 
1339 MODULE_AUTHOR("Nancy Lin");
1340 MODULE_AUTHOR("Steve Glendinning <steve.glendinning@smsc.com>");
1341 MODULE_DESCRIPTION("SMSC95XX USB 2.0 Ethernet Devices");
1342 MODULE_LICENSE("GPL");
1343