1 /*
2  * Microchip ENC28J60 ethernet driver (MAC + PHY)
3  *
4  * Copyright (C) 2007 Eurek srl
5  * Author: Claudio Lanconelli <lanconelli.claudio@eptar.com>
6  * based on enc28j60.c written by David Anders for 2.4 kernel version
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * $Id: enc28j60.c,v 1.22 2007/12/20 10:47:01 claudio Exp $
14  */
15 
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/types.h>
19 #include <linux/fcntl.h>
20 #include <linux/interrupt.h>
21 #include <linux/string.h>
22 #include <linux/errno.h>
23 #include <linux/init.h>
24 #include <linux/netdevice.h>
25 #include <linux/etherdevice.h>
26 #include <linux/ethtool.h>
27 #include <linux/tcp.h>
28 #include <linux/skbuff.h>
29 #include <linux/delay.h>
30 #include <linux/spi/spi.h>
31 
32 #include "enc28j60_hw.h"
33 
34 #define DRV_NAME	"enc28j60"
35 #define DRV_VERSION	"1.01"
36 
37 #define SPI_OPLEN	1
38 
39 #define ENC28J60_MSG_DEFAULT	\
40 	(NETIF_MSG_PROBE | NETIF_MSG_IFUP | NETIF_MSG_IFDOWN | NETIF_MSG_LINK)
41 
42 /* Buffer size required for the largest SPI transfer (i.e., reading a
43  * frame). */
44 #define SPI_TRANSFER_BUF_LEN	(4 + MAX_FRAMELEN)
45 
46 #define TX_TIMEOUT	(4 * HZ)
47 
48 /* Max TX retries in case of collision as suggested by errata datasheet */
49 #define MAX_TX_RETRYCOUNT	16
50 
51 enum {
52 	RXFILTER_NORMAL,
53 	RXFILTER_MULTI,
54 	RXFILTER_PROMISC
55 };
56 
57 /* Driver local data */
58 struct enc28j60_net {
59 	struct net_device *netdev;
60 	struct spi_device *spi;
61 	struct mutex lock;
62 	struct sk_buff *tx_skb;
63 	struct work_struct tx_work;
64 	struct work_struct irq_work;
65 	struct work_struct setrx_work;
66 	struct work_struct restart_work;
67 	u8 bank;		/* current register bank selected */
68 	u16 next_pk_ptr;	/* next packet pointer within FIFO */
69 	u16 max_pk_counter;	/* statistics: max packet counter */
70 	u16 tx_retry_count;
71 	bool hw_enable;
72 	bool full_duplex;
73 	int rxfilter;
74 	u32 msg_enable;
75 	u8 spi_transfer_buf[SPI_TRANSFER_BUF_LEN];
76 };
77 
78 /* use ethtool to change the level for any given device */
79 static struct {
80 	u32 msg_enable;
81 } debug = { -1 };
82 
83 /*
84  * SPI read buffer
85  * wait for the SPI transfer and copy received data to destination
86  */
87 static int
88 spi_read_buf(struct enc28j60_net *priv, int len, u8 *data)
89 {
90 	u8 *rx_buf = priv->spi_transfer_buf + 4;
91 	u8 *tx_buf = priv->spi_transfer_buf;
92 	struct spi_transfer t = {
93 		.tx_buf = tx_buf,
94 		.rx_buf = rx_buf,
95 		.len = SPI_OPLEN + len,
96 	};
97 	struct spi_message msg;
98 	int ret;
99 
100 	tx_buf[0] = ENC28J60_READ_BUF_MEM;
101 	tx_buf[1] = tx_buf[2] = tx_buf[3] = 0;	/* don't care */
102 
103 	spi_message_init(&msg);
104 	spi_message_add_tail(&t, &msg);
105 	ret = spi_sync(priv->spi, &msg);
106 	if (ret == 0) {
107 		memcpy(data, &rx_buf[SPI_OPLEN], len);
108 		ret = msg.status;
109 	}
110 	if (ret && netif_msg_drv(priv))
111 		printk(KERN_DEBUG DRV_NAME ": %s() failed: ret = %d\n",
112 			__func__, ret);
113 
114 	return ret;
115 }
116 
117 /*
118  * SPI write buffer
119  */
120 static int spi_write_buf(struct enc28j60_net *priv, int len,
121 			 const u8 *data)
122 {
123 	int ret;
124 
125 	if (len > SPI_TRANSFER_BUF_LEN - 1 || len <= 0)
126 		ret = -EINVAL;
127 	else {
128 		priv->spi_transfer_buf[0] = ENC28J60_WRITE_BUF_MEM;
129 		memcpy(&priv->spi_transfer_buf[1], data, len);
130 		ret = spi_write(priv->spi, priv->spi_transfer_buf, len + 1);
131 		if (ret && netif_msg_drv(priv))
132 			printk(KERN_DEBUG DRV_NAME ": %s() failed: ret = %d\n",
133 				__func__, ret);
134 	}
135 	return ret;
136 }
137 
138 /*
139  * basic SPI read operation
140  */
141 static u8 spi_read_op(struct enc28j60_net *priv, u8 op,
142 			   u8 addr)
143 {
144 	u8 tx_buf[2];
145 	u8 rx_buf[4];
146 	u8 val = 0;
147 	int ret;
148 	int slen = SPI_OPLEN;
149 
150 	/* do dummy read if needed */
151 	if (addr & SPRD_MASK)
152 		slen++;
153 
154 	tx_buf[0] = op | (addr & ADDR_MASK);
155 	ret = spi_write_then_read(priv->spi, tx_buf, 1, rx_buf, slen);
156 	if (ret)
157 		printk(KERN_DEBUG DRV_NAME ": %s() failed: ret = %d\n",
158 			__func__, ret);
159 	else
160 		val = rx_buf[slen - 1];
161 
162 	return val;
163 }
164 
165 /*
166  * basic SPI write operation
167  */
168 static int spi_write_op(struct enc28j60_net *priv, u8 op,
169 			u8 addr, u8 val)
170 {
171 	int ret;
172 
173 	priv->spi_transfer_buf[0] = op | (addr & ADDR_MASK);
174 	priv->spi_transfer_buf[1] = val;
175 	ret = spi_write(priv->spi, priv->spi_transfer_buf, 2);
176 	if (ret && netif_msg_drv(priv))
177 		printk(KERN_DEBUG DRV_NAME ": %s() failed: ret = %d\n",
178 			__func__, ret);
179 	return ret;
180 }
181 
182 static void enc28j60_soft_reset(struct enc28j60_net *priv)
183 {
184 	if (netif_msg_hw(priv))
185 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
186 
187 	spi_write_op(priv, ENC28J60_SOFT_RESET, 0, ENC28J60_SOFT_RESET);
188 	/* Errata workaround #1, CLKRDY check is unreliable,
189 	 * delay at least 1 mS instead */
190 	udelay(2000);
191 }
192 
193 /*
194  * select the current register bank if necessary
195  */
196 static void enc28j60_set_bank(struct enc28j60_net *priv, u8 addr)
197 {
198 	u8 b = (addr & BANK_MASK) >> 5;
199 
200 	/* These registers (EIE, EIR, ESTAT, ECON2, ECON1)
201 	 * are present in all banks, no need to switch bank
202 	 */
203 	if (addr >= EIE && addr <= ECON1)
204 		return;
205 
206 	/* Clear or set each bank selection bit as needed */
207 	if ((b & ECON1_BSEL0) != (priv->bank & ECON1_BSEL0)) {
208 		if (b & ECON1_BSEL0)
209 			spi_write_op(priv, ENC28J60_BIT_FIELD_SET, ECON1,
210 					ECON1_BSEL0);
211 		else
212 			spi_write_op(priv, ENC28J60_BIT_FIELD_CLR, ECON1,
213 					ECON1_BSEL0);
214 	}
215 	if ((b & ECON1_BSEL1) != (priv->bank & ECON1_BSEL1)) {
216 		if (b & ECON1_BSEL1)
217 			spi_write_op(priv, ENC28J60_BIT_FIELD_SET, ECON1,
218 					ECON1_BSEL1);
219 		else
220 			spi_write_op(priv, ENC28J60_BIT_FIELD_CLR, ECON1,
221 					ECON1_BSEL1);
222 	}
223 	priv->bank = b;
224 }
225 
226 /*
227  * Register access routines through the SPI bus.
228  * Every register access comes in two flavours:
229  * - nolock_xxx: caller needs to invoke mutex_lock, usually to access
230  *   atomically more than one register
231  * - locked_xxx: caller doesn't need to invoke mutex_lock, single access
232  *
233  * Some registers can be accessed through the bit field clear and
234  * bit field set to avoid a read modify write cycle.
235  */
236 
237 /*
238  * Register bit field Set
239  */
240 static void nolock_reg_bfset(struct enc28j60_net *priv,
241 				      u8 addr, u8 mask)
242 {
243 	enc28j60_set_bank(priv, addr);
244 	spi_write_op(priv, ENC28J60_BIT_FIELD_SET, addr, mask);
245 }
246 
247 static void locked_reg_bfset(struct enc28j60_net *priv,
248 				      u8 addr, u8 mask)
249 {
250 	mutex_lock(&priv->lock);
251 	nolock_reg_bfset(priv, addr, mask);
252 	mutex_unlock(&priv->lock);
253 }
254 
255 /*
256  * Register bit field Clear
257  */
258 static void nolock_reg_bfclr(struct enc28j60_net *priv,
259 				      u8 addr, u8 mask)
260 {
261 	enc28j60_set_bank(priv, addr);
262 	spi_write_op(priv, ENC28J60_BIT_FIELD_CLR, addr, mask);
263 }
264 
265 static void locked_reg_bfclr(struct enc28j60_net *priv,
266 				      u8 addr, u8 mask)
267 {
268 	mutex_lock(&priv->lock);
269 	nolock_reg_bfclr(priv, addr, mask);
270 	mutex_unlock(&priv->lock);
271 }
272 
273 /*
274  * Register byte read
275  */
276 static int nolock_regb_read(struct enc28j60_net *priv,
277 				     u8 address)
278 {
279 	enc28j60_set_bank(priv, address);
280 	return spi_read_op(priv, ENC28J60_READ_CTRL_REG, address);
281 }
282 
283 static int locked_regb_read(struct enc28j60_net *priv,
284 				     u8 address)
285 {
286 	int ret;
287 
288 	mutex_lock(&priv->lock);
289 	ret = nolock_regb_read(priv, address);
290 	mutex_unlock(&priv->lock);
291 
292 	return ret;
293 }
294 
295 /*
296  * Register word read
297  */
298 static int nolock_regw_read(struct enc28j60_net *priv,
299 				     u8 address)
300 {
301 	int rl, rh;
302 
303 	enc28j60_set_bank(priv, address);
304 	rl = spi_read_op(priv, ENC28J60_READ_CTRL_REG, address);
305 	rh = spi_read_op(priv, ENC28J60_READ_CTRL_REG, address + 1);
306 
307 	return (rh << 8) | rl;
308 }
309 
310 static int locked_regw_read(struct enc28j60_net *priv,
311 				     u8 address)
312 {
313 	int ret;
314 
315 	mutex_lock(&priv->lock);
316 	ret = nolock_regw_read(priv, address);
317 	mutex_unlock(&priv->lock);
318 
319 	return ret;
320 }
321 
322 /*
323  * Register byte write
324  */
325 static void nolock_regb_write(struct enc28j60_net *priv,
326 				       u8 address, u8 data)
327 {
328 	enc28j60_set_bank(priv, address);
329 	spi_write_op(priv, ENC28J60_WRITE_CTRL_REG, address, data);
330 }
331 
332 static void locked_regb_write(struct enc28j60_net *priv,
333 				       u8 address, u8 data)
334 {
335 	mutex_lock(&priv->lock);
336 	nolock_regb_write(priv, address, data);
337 	mutex_unlock(&priv->lock);
338 }
339 
340 /*
341  * Register word write
342  */
343 static void nolock_regw_write(struct enc28j60_net *priv,
344 				       u8 address, u16 data)
345 {
346 	enc28j60_set_bank(priv, address);
347 	spi_write_op(priv, ENC28J60_WRITE_CTRL_REG, address, (u8) data);
348 	spi_write_op(priv, ENC28J60_WRITE_CTRL_REG, address + 1,
349 		     (u8) (data >> 8));
350 }
351 
352 static void locked_regw_write(struct enc28j60_net *priv,
353 				       u8 address, u16 data)
354 {
355 	mutex_lock(&priv->lock);
356 	nolock_regw_write(priv, address, data);
357 	mutex_unlock(&priv->lock);
358 }
359 
360 /*
361  * Buffer memory read
362  * Select the starting address and execute a SPI buffer read
363  */
364 static void enc28j60_mem_read(struct enc28j60_net *priv,
365 				     u16 addr, int len, u8 *data)
366 {
367 	mutex_lock(&priv->lock);
368 	nolock_regw_write(priv, ERDPTL, addr);
369 #ifdef CONFIG_ENC28J60_WRITEVERIFY
370 	if (netif_msg_drv(priv)) {
371 		u16 reg;
372 		reg = nolock_regw_read(priv, ERDPTL);
373 		if (reg != addr)
374 			printk(KERN_DEBUG DRV_NAME ": %s() error writing ERDPT "
375 				"(0x%04x - 0x%04x)\n", __func__, reg, addr);
376 	}
377 #endif
378 	spi_read_buf(priv, len, data);
379 	mutex_unlock(&priv->lock);
380 }
381 
382 /*
383  * Write packet to enc28j60 TX buffer memory
384  */
385 static void
386 enc28j60_packet_write(struct enc28j60_net *priv, int len, const u8 *data)
387 {
388 	mutex_lock(&priv->lock);
389 	/* Set the write pointer to start of transmit buffer area */
390 	nolock_regw_write(priv, EWRPTL, TXSTART_INIT);
391 #ifdef CONFIG_ENC28J60_WRITEVERIFY
392 	if (netif_msg_drv(priv)) {
393 		u16 reg;
394 		reg = nolock_regw_read(priv, EWRPTL);
395 		if (reg != TXSTART_INIT)
396 			printk(KERN_DEBUG DRV_NAME
397 				": %s() ERWPT:0x%04x != 0x%04x\n",
398 				__func__, reg, TXSTART_INIT);
399 	}
400 #endif
401 	/* Set the TXND pointer to correspond to the packet size given */
402 	nolock_regw_write(priv, ETXNDL, TXSTART_INIT + len);
403 	/* write per-packet control byte */
404 	spi_write_op(priv, ENC28J60_WRITE_BUF_MEM, 0, 0x00);
405 	if (netif_msg_hw(priv))
406 		printk(KERN_DEBUG DRV_NAME
407 			": %s() after control byte ERWPT:0x%04x\n",
408 			__func__, nolock_regw_read(priv, EWRPTL));
409 	/* copy the packet into the transmit buffer */
410 	spi_write_buf(priv, len, data);
411 	if (netif_msg_hw(priv))
412 		printk(KERN_DEBUG DRV_NAME
413 			 ": %s() after write packet ERWPT:0x%04x, len=%d\n",
414 			 __func__, nolock_regw_read(priv, EWRPTL), len);
415 	mutex_unlock(&priv->lock);
416 }
417 
418 static unsigned long msec20_to_jiffies;
419 
420 static int poll_ready(struct enc28j60_net *priv, u8 reg, u8 mask, u8 val)
421 {
422 	unsigned long timeout = jiffies + msec20_to_jiffies;
423 
424 	/* 20 msec timeout read */
425 	while ((nolock_regb_read(priv, reg) & mask) != val) {
426 		if (time_after(jiffies, timeout)) {
427 			if (netif_msg_drv(priv))
428 				dev_dbg(&priv->spi->dev,
429 					"reg %02x ready timeout!\n", reg);
430 			return -ETIMEDOUT;
431 		}
432 		cpu_relax();
433 	}
434 	return 0;
435 }
436 
437 /*
438  * Wait until the PHY operation is complete.
439  */
440 static int wait_phy_ready(struct enc28j60_net *priv)
441 {
442 	return poll_ready(priv, MISTAT, MISTAT_BUSY, 0) ? 0 : 1;
443 }
444 
445 /*
446  * PHY register read
447  * PHY registers are not accessed directly, but through the MII
448  */
449 static u16 enc28j60_phy_read(struct enc28j60_net *priv, u8 address)
450 {
451 	u16 ret;
452 
453 	mutex_lock(&priv->lock);
454 	/* set the PHY register address */
455 	nolock_regb_write(priv, MIREGADR, address);
456 	/* start the register read operation */
457 	nolock_regb_write(priv, MICMD, MICMD_MIIRD);
458 	/* wait until the PHY read completes */
459 	wait_phy_ready(priv);
460 	/* quit reading */
461 	nolock_regb_write(priv, MICMD, 0x00);
462 	/* return the data */
463 	ret  = nolock_regw_read(priv, MIRDL);
464 	mutex_unlock(&priv->lock);
465 
466 	return ret;
467 }
468 
469 static int enc28j60_phy_write(struct enc28j60_net *priv, u8 address, u16 data)
470 {
471 	int ret;
472 
473 	mutex_lock(&priv->lock);
474 	/* set the PHY register address */
475 	nolock_regb_write(priv, MIREGADR, address);
476 	/* write the PHY data */
477 	nolock_regw_write(priv, MIWRL, data);
478 	/* wait until the PHY write completes and return */
479 	ret = wait_phy_ready(priv);
480 	mutex_unlock(&priv->lock);
481 
482 	return ret;
483 }
484 
485 /*
486  * Program the hardware MAC address from dev->dev_addr.
487  */
488 static int enc28j60_set_hw_macaddr(struct net_device *ndev)
489 {
490 	int ret;
491 	struct enc28j60_net *priv = netdev_priv(ndev);
492 
493 	mutex_lock(&priv->lock);
494 	if (!priv->hw_enable) {
495 		if (netif_msg_drv(priv))
496 			printk(KERN_INFO DRV_NAME
497 				": %s: Setting MAC address to %pM\n",
498 				ndev->name, ndev->dev_addr);
499 		/* NOTE: MAC address in ENC28J60 is byte-backward */
500 		nolock_regb_write(priv, MAADR5, ndev->dev_addr[0]);
501 		nolock_regb_write(priv, MAADR4, ndev->dev_addr[1]);
502 		nolock_regb_write(priv, MAADR3, ndev->dev_addr[2]);
503 		nolock_regb_write(priv, MAADR2, ndev->dev_addr[3]);
504 		nolock_regb_write(priv, MAADR1, ndev->dev_addr[4]);
505 		nolock_regb_write(priv, MAADR0, ndev->dev_addr[5]);
506 		ret = 0;
507 	} else {
508 		if (netif_msg_drv(priv))
509 			printk(KERN_DEBUG DRV_NAME
510 				": %s() Hardware must be disabled to set "
511 				"Mac address\n", __func__);
512 		ret = -EBUSY;
513 	}
514 	mutex_unlock(&priv->lock);
515 	return ret;
516 }
517 
518 /*
519  * Store the new hardware address in dev->dev_addr, and update the MAC.
520  */
521 static int enc28j60_set_mac_address(struct net_device *dev, void *addr)
522 {
523 	struct sockaddr *address = addr;
524 
525 	if (netif_running(dev))
526 		return -EBUSY;
527 	if (!is_valid_ether_addr(address->sa_data))
528 		return -EADDRNOTAVAIL;
529 
530 	memcpy(dev->dev_addr, address->sa_data, dev->addr_len);
531 	return enc28j60_set_hw_macaddr(dev);
532 }
533 
534 /*
535  * Debug routine to dump useful register contents
536  */
537 static void enc28j60_dump_regs(struct enc28j60_net *priv, const char *msg)
538 {
539 	mutex_lock(&priv->lock);
540 	printk(KERN_DEBUG DRV_NAME " %s\n"
541 		"HwRevID: 0x%02x\n"
542 		"Cntrl: ECON1 ECON2 ESTAT  EIR  EIE\n"
543 		"       0x%02x  0x%02x  0x%02x  0x%02x  0x%02x\n"
544 		"MAC  : MACON1 MACON3 MACON4\n"
545 		"       0x%02x   0x%02x   0x%02x\n"
546 		"Rx   : ERXST  ERXND  ERXWRPT ERXRDPT ERXFCON EPKTCNT MAMXFL\n"
547 		"       0x%04x 0x%04x 0x%04x  0x%04x  "
548 		"0x%02x    0x%02x    0x%04x\n"
549 		"Tx   : ETXST  ETXND  MACLCON1 MACLCON2 MAPHSUP\n"
550 		"       0x%04x 0x%04x 0x%02x     0x%02x     0x%02x\n",
551 		msg, nolock_regb_read(priv, EREVID),
552 		nolock_regb_read(priv, ECON1), nolock_regb_read(priv, ECON2),
553 		nolock_regb_read(priv, ESTAT), nolock_regb_read(priv, EIR),
554 		nolock_regb_read(priv, EIE), nolock_regb_read(priv, MACON1),
555 		nolock_regb_read(priv, MACON3), nolock_regb_read(priv, MACON4),
556 		nolock_regw_read(priv, ERXSTL), nolock_regw_read(priv, ERXNDL),
557 		nolock_regw_read(priv, ERXWRPTL),
558 		nolock_regw_read(priv, ERXRDPTL),
559 		nolock_regb_read(priv, ERXFCON),
560 		nolock_regb_read(priv, EPKTCNT),
561 		nolock_regw_read(priv, MAMXFLL), nolock_regw_read(priv, ETXSTL),
562 		nolock_regw_read(priv, ETXNDL),
563 		nolock_regb_read(priv, MACLCON1),
564 		nolock_regb_read(priv, MACLCON2),
565 		nolock_regb_read(priv, MAPHSUP));
566 	mutex_unlock(&priv->lock);
567 }
568 
569 /*
570  * ERXRDPT need to be set always at odd addresses, refer to errata datasheet
571  */
572 static u16 erxrdpt_workaround(u16 next_packet_ptr, u16 start, u16 end)
573 {
574 	u16 erxrdpt;
575 
576 	if ((next_packet_ptr - 1 < start) || (next_packet_ptr - 1 > end))
577 		erxrdpt = end;
578 	else
579 		erxrdpt = next_packet_ptr - 1;
580 
581 	return erxrdpt;
582 }
583 
584 /*
585  * Calculate wrap around when reading beyond the end of the RX buffer
586  */
587 static u16 rx_packet_start(u16 ptr)
588 {
589 	if (ptr + RSV_SIZE > RXEND_INIT)
590 		return (ptr + RSV_SIZE) - (RXEND_INIT - RXSTART_INIT + 1);
591 	else
592 		return ptr + RSV_SIZE;
593 }
594 
595 static void nolock_rxfifo_init(struct enc28j60_net *priv, u16 start, u16 end)
596 {
597 	u16 erxrdpt;
598 
599 	if (start > 0x1FFF || end > 0x1FFF || start > end) {
600 		if (netif_msg_drv(priv))
601 			printk(KERN_ERR DRV_NAME ": %s(%d, %d) RXFIFO "
602 				"bad parameters!\n", __func__, start, end);
603 		return;
604 	}
605 	/* set receive buffer start + end */
606 	priv->next_pk_ptr = start;
607 	nolock_regw_write(priv, ERXSTL, start);
608 	erxrdpt = erxrdpt_workaround(priv->next_pk_ptr, start, end);
609 	nolock_regw_write(priv, ERXRDPTL, erxrdpt);
610 	nolock_regw_write(priv, ERXNDL, end);
611 }
612 
613 static void nolock_txfifo_init(struct enc28j60_net *priv, u16 start, u16 end)
614 {
615 	if (start > 0x1FFF || end > 0x1FFF || start > end) {
616 		if (netif_msg_drv(priv))
617 			printk(KERN_ERR DRV_NAME ": %s(%d, %d) TXFIFO "
618 				"bad parameters!\n", __func__, start, end);
619 		return;
620 	}
621 	/* set transmit buffer start + end */
622 	nolock_regw_write(priv, ETXSTL, start);
623 	nolock_regw_write(priv, ETXNDL, end);
624 }
625 
626 /*
627  * Low power mode shrinks power consumption about 100x, so we'd like
628  * the chip to be in that mode whenever it's inactive.  (However, we
629  * can't stay in lowpower mode during suspend with WOL active.)
630  */
631 static void enc28j60_lowpower(struct enc28j60_net *priv, bool is_low)
632 {
633 	if (netif_msg_drv(priv))
634 		dev_dbg(&priv->spi->dev, "%s power...\n",
635 				is_low ? "low" : "high");
636 
637 	mutex_lock(&priv->lock);
638 	if (is_low) {
639 		nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
640 		poll_ready(priv, ESTAT, ESTAT_RXBUSY, 0);
641 		poll_ready(priv, ECON1, ECON1_TXRTS, 0);
642 		/* ECON2_VRPS was set during initialization */
643 		nolock_reg_bfset(priv, ECON2, ECON2_PWRSV);
644 	} else {
645 		nolock_reg_bfclr(priv, ECON2, ECON2_PWRSV);
646 		poll_ready(priv, ESTAT, ESTAT_CLKRDY, ESTAT_CLKRDY);
647 		/* caller sets ECON1_RXEN */
648 	}
649 	mutex_unlock(&priv->lock);
650 }
651 
652 static int enc28j60_hw_init(struct enc28j60_net *priv)
653 {
654 	u8 reg;
655 
656 	if (netif_msg_drv(priv))
657 		printk(KERN_DEBUG DRV_NAME ": %s() - %s\n", __func__,
658 			priv->full_duplex ? "FullDuplex" : "HalfDuplex");
659 
660 	mutex_lock(&priv->lock);
661 	/* first reset the chip */
662 	enc28j60_soft_reset(priv);
663 	/* Clear ECON1 */
664 	spi_write_op(priv, ENC28J60_WRITE_CTRL_REG, ECON1, 0x00);
665 	priv->bank = 0;
666 	priv->hw_enable = false;
667 	priv->tx_retry_count = 0;
668 	priv->max_pk_counter = 0;
669 	priv->rxfilter = RXFILTER_NORMAL;
670 	/* enable address auto increment and voltage regulator powersave */
671 	nolock_regb_write(priv, ECON2, ECON2_AUTOINC | ECON2_VRPS);
672 
673 	nolock_rxfifo_init(priv, RXSTART_INIT, RXEND_INIT);
674 	nolock_txfifo_init(priv, TXSTART_INIT, TXEND_INIT);
675 	mutex_unlock(&priv->lock);
676 
677 	/*
678 	 * Check the RevID.
679 	 * If it's 0x00 or 0xFF probably the enc28j60 is not mounted or
680 	 * damaged
681 	 */
682 	reg = locked_regb_read(priv, EREVID);
683 	if (netif_msg_drv(priv))
684 		printk(KERN_INFO DRV_NAME ": chip RevID: 0x%02x\n", reg);
685 	if (reg == 0x00 || reg == 0xff) {
686 		if (netif_msg_drv(priv))
687 			printk(KERN_DEBUG DRV_NAME ": %s() Invalid RevId %d\n",
688 				__func__, reg);
689 		return 0;
690 	}
691 
692 	/* default filter mode: (unicast OR broadcast) AND crc valid */
693 	locked_regb_write(priv, ERXFCON,
694 			    ERXFCON_UCEN | ERXFCON_CRCEN | ERXFCON_BCEN);
695 
696 	/* enable MAC receive */
697 	locked_regb_write(priv, MACON1,
698 			    MACON1_MARXEN | MACON1_TXPAUS | MACON1_RXPAUS);
699 	/* enable automatic padding and CRC operations */
700 	if (priv->full_duplex) {
701 		locked_regb_write(priv, MACON3,
702 				    MACON3_PADCFG0 | MACON3_TXCRCEN |
703 				    MACON3_FRMLNEN | MACON3_FULDPX);
704 		/* set inter-frame gap (non-back-to-back) */
705 		locked_regb_write(priv, MAIPGL, 0x12);
706 		/* set inter-frame gap (back-to-back) */
707 		locked_regb_write(priv, MABBIPG, 0x15);
708 	} else {
709 		locked_regb_write(priv, MACON3,
710 				    MACON3_PADCFG0 | MACON3_TXCRCEN |
711 				    MACON3_FRMLNEN);
712 		locked_regb_write(priv, MACON4, 1 << 6);	/* DEFER bit */
713 		/* set inter-frame gap (non-back-to-back) */
714 		locked_regw_write(priv, MAIPGL, 0x0C12);
715 		/* set inter-frame gap (back-to-back) */
716 		locked_regb_write(priv, MABBIPG, 0x12);
717 	}
718 	/*
719 	 * MACLCON1 (default)
720 	 * MACLCON2 (default)
721 	 * Set the maximum packet size which the controller will accept
722 	 */
723 	locked_regw_write(priv, MAMXFLL, MAX_FRAMELEN);
724 
725 	/* Configure LEDs */
726 	if (!enc28j60_phy_write(priv, PHLCON, ENC28J60_LAMPS_MODE))
727 		return 0;
728 
729 	if (priv->full_duplex) {
730 		if (!enc28j60_phy_write(priv, PHCON1, PHCON1_PDPXMD))
731 			return 0;
732 		if (!enc28j60_phy_write(priv, PHCON2, 0x00))
733 			return 0;
734 	} else {
735 		if (!enc28j60_phy_write(priv, PHCON1, 0x00))
736 			return 0;
737 		if (!enc28j60_phy_write(priv, PHCON2, PHCON2_HDLDIS))
738 			return 0;
739 	}
740 	if (netif_msg_hw(priv))
741 		enc28j60_dump_regs(priv, "Hw initialized.");
742 
743 	return 1;
744 }
745 
746 static void enc28j60_hw_enable(struct enc28j60_net *priv)
747 {
748 	/* enable interrupts */
749 	if (netif_msg_hw(priv))
750 		printk(KERN_DEBUG DRV_NAME ": %s() enabling interrupts.\n",
751 			__func__);
752 
753 	enc28j60_phy_write(priv, PHIE, PHIE_PGEIE | PHIE_PLNKIE);
754 
755 	mutex_lock(&priv->lock);
756 	nolock_reg_bfclr(priv, EIR, EIR_DMAIF | EIR_LINKIF |
757 			 EIR_TXIF | EIR_TXERIF | EIR_RXERIF | EIR_PKTIF);
758 	nolock_regb_write(priv, EIE, EIE_INTIE | EIE_PKTIE | EIE_LINKIE |
759 			  EIE_TXIE | EIE_TXERIE | EIE_RXERIE);
760 
761 	/* enable receive logic */
762 	nolock_reg_bfset(priv, ECON1, ECON1_RXEN);
763 	priv->hw_enable = true;
764 	mutex_unlock(&priv->lock);
765 }
766 
767 static void enc28j60_hw_disable(struct enc28j60_net *priv)
768 {
769 	mutex_lock(&priv->lock);
770 	/* disable interrutps and packet reception */
771 	nolock_regb_write(priv, EIE, 0x00);
772 	nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
773 	priv->hw_enable = false;
774 	mutex_unlock(&priv->lock);
775 }
776 
777 static int
778 enc28j60_setlink(struct net_device *ndev, u8 autoneg, u16 speed, u8 duplex)
779 {
780 	struct enc28j60_net *priv = netdev_priv(ndev);
781 	int ret = 0;
782 
783 	if (!priv->hw_enable) {
784 		/* link is in low power mode now; duplex setting
785 		 * will take effect on next enc28j60_hw_init().
786 		 */
787 		if (autoneg == AUTONEG_DISABLE && speed == SPEED_10)
788 			priv->full_duplex = (duplex == DUPLEX_FULL);
789 		else {
790 			if (netif_msg_link(priv))
791 				dev_warn(&ndev->dev,
792 					"unsupported link setting\n");
793 			ret = -EOPNOTSUPP;
794 		}
795 	} else {
796 		if (netif_msg_link(priv))
797 			dev_warn(&ndev->dev, "Warning: hw must be disabled "
798 				"to set link mode\n");
799 		ret = -EBUSY;
800 	}
801 	return ret;
802 }
803 
804 /*
805  * Read the Transmit Status Vector
806  */
807 static void enc28j60_read_tsv(struct enc28j60_net *priv, u8 tsv[TSV_SIZE])
808 {
809 	int endptr;
810 
811 	endptr = locked_regw_read(priv, ETXNDL);
812 	if (netif_msg_hw(priv))
813 		printk(KERN_DEBUG DRV_NAME ": reading TSV at addr:0x%04x\n",
814 			 endptr + 1);
815 	enc28j60_mem_read(priv, endptr + 1, TSV_SIZE, tsv);
816 }
817 
818 static void enc28j60_dump_tsv(struct enc28j60_net *priv, const char *msg,
819 				u8 tsv[TSV_SIZE])
820 {
821 	u16 tmp1, tmp2;
822 
823 	printk(KERN_DEBUG DRV_NAME ": %s - TSV:\n", msg);
824 	tmp1 = tsv[1];
825 	tmp1 <<= 8;
826 	tmp1 |= tsv[0];
827 
828 	tmp2 = tsv[5];
829 	tmp2 <<= 8;
830 	tmp2 |= tsv[4];
831 
832 	printk(KERN_DEBUG DRV_NAME ": ByteCount: %d, CollisionCount: %d,"
833 		" TotByteOnWire: %d\n", tmp1, tsv[2] & 0x0f, tmp2);
834 	printk(KERN_DEBUG DRV_NAME ": TxDone: %d, CRCErr:%d, LenChkErr: %d,"
835 		" LenOutOfRange: %d\n", TSV_GETBIT(tsv, TSV_TXDONE),
836 		TSV_GETBIT(tsv, TSV_TXCRCERROR),
837 		TSV_GETBIT(tsv, TSV_TXLENCHKERROR),
838 		TSV_GETBIT(tsv, TSV_TXLENOUTOFRANGE));
839 	printk(KERN_DEBUG DRV_NAME ": Multicast: %d, Broadcast: %d, "
840 		"PacketDefer: %d, ExDefer: %d\n",
841 		TSV_GETBIT(tsv, TSV_TXMULTICAST),
842 		TSV_GETBIT(tsv, TSV_TXBROADCAST),
843 		TSV_GETBIT(tsv, TSV_TXPACKETDEFER),
844 		TSV_GETBIT(tsv, TSV_TXEXDEFER));
845 	printk(KERN_DEBUG DRV_NAME ": ExCollision: %d, LateCollision: %d, "
846 		 "Giant: %d, Underrun: %d\n",
847 		 TSV_GETBIT(tsv, TSV_TXEXCOLLISION),
848 		 TSV_GETBIT(tsv, TSV_TXLATECOLLISION),
849 		 TSV_GETBIT(tsv, TSV_TXGIANT), TSV_GETBIT(tsv, TSV_TXUNDERRUN));
850 	printk(KERN_DEBUG DRV_NAME ": ControlFrame: %d, PauseFrame: %d, "
851 		 "BackPressApp: %d, VLanTagFrame: %d\n",
852 		 TSV_GETBIT(tsv, TSV_TXCONTROLFRAME),
853 		 TSV_GETBIT(tsv, TSV_TXPAUSEFRAME),
854 		 TSV_GETBIT(tsv, TSV_BACKPRESSUREAPP),
855 		 TSV_GETBIT(tsv, TSV_TXVLANTAGFRAME));
856 }
857 
858 /*
859  * Receive Status vector
860  */
861 static void enc28j60_dump_rsv(struct enc28j60_net *priv, const char *msg,
862 			      u16 pk_ptr, int len, u16 sts)
863 {
864 	printk(KERN_DEBUG DRV_NAME ": %s - NextPk: 0x%04x - RSV:\n",
865 		msg, pk_ptr);
866 	printk(KERN_DEBUG DRV_NAME ": ByteCount: %d, DribbleNibble: %d\n", len,
867 		 RSV_GETBIT(sts, RSV_DRIBBLENIBBLE));
868 	printk(KERN_DEBUG DRV_NAME ": RxOK: %d, CRCErr:%d, LenChkErr: %d,"
869 		 " LenOutOfRange: %d\n", RSV_GETBIT(sts, RSV_RXOK),
870 		 RSV_GETBIT(sts, RSV_CRCERROR),
871 		 RSV_GETBIT(sts, RSV_LENCHECKERR),
872 		 RSV_GETBIT(sts, RSV_LENOUTOFRANGE));
873 	printk(KERN_DEBUG DRV_NAME ": Multicast: %d, Broadcast: %d, "
874 		 "LongDropEvent: %d, CarrierEvent: %d\n",
875 		 RSV_GETBIT(sts, RSV_RXMULTICAST),
876 		 RSV_GETBIT(sts, RSV_RXBROADCAST),
877 		 RSV_GETBIT(sts, RSV_RXLONGEVDROPEV),
878 		 RSV_GETBIT(sts, RSV_CARRIEREV));
879 	printk(KERN_DEBUG DRV_NAME ": ControlFrame: %d, PauseFrame: %d,"
880 		 " UnknownOp: %d, VLanTagFrame: %d\n",
881 		 RSV_GETBIT(sts, RSV_RXCONTROLFRAME),
882 		 RSV_GETBIT(sts, RSV_RXPAUSEFRAME),
883 		 RSV_GETBIT(sts, RSV_RXUNKNOWNOPCODE),
884 		 RSV_GETBIT(sts, RSV_RXTYPEVLAN));
885 }
886 
887 static void dump_packet(const char *msg, int len, const char *data)
888 {
889 	printk(KERN_DEBUG DRV_NAME ": %s - packet len:%d\n", msg, len);
890 	print_hex_dump(KERN_DEBUG, "pk data: ", DUMP_PREFIX_OFFSET, 16, 1,
891 			data, len, true);
892 }
893 
894 /*
895  * Hardware receive function.
896  * Read the buffer memory, update the FIFO pointer to free the buffer,
897  * check the status vector and decrement the packet counter.
898  */
899 static void enc28j60_hw_rx(struct net_device *ndev)
900 {
901 	struct enc28j60_net *priv = netdev_priv(ndev);
902 	struct sk_buff *skb = NULL;
903 	u16 erxrdpt, next_packet, rxstat;
904 	u8 rsv[RSV_SIZE];
905 	int len;
906 
907 	if (netif_msg_rx_status(priv))
908 		printk(KERN_DEBUG DRV_NAME ": RX pk_addr:0x%04x\n",
909 			priv->next_pk_ptr);
910 
911 	if (unlikely(priv->next_pk_ptr > RXEND_INIT)) {
912 		if (netif_msg_rx_err(priv))
913 			dev_err(&ndev->dev,
914 				"%s() Invalid packet address!! 0x%04x\n",
915 				__func__, priv->next_pk_ptr);
916 		/* packet address corrupted: reset RX logic */
917 		mutex_lock(&priv->lock);
918 		nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
919 		nolock_reg_bfset(priv, ECON1, ECON1_RXRST);
920 		nolock_reg_bfclr(priv, ECON1, ECON1_RXRST);
921 		nolock_rxfifo_init(priv, RXSTART_INIT, RXEND_INIT);
922 		nolock_reg_bfclr(priv, EIR, EIR_RXERIF);
923 		nolock_reg_bfset(priv, ECON1, ECON1_RXEN);
924 		mutex_unlock(&priv->lock);
925 		ndev->stats.rx_errors++;
926 		return;
927 	}
928 	/* Read next packet pointer and rx status vector */
929 	enc28j60_mem_read(priv, priv->next_pk_ptr, sizeof(rsv), rsv);
930 
931 	next_packet = rsv[1];
932 	next_packet <<= 8;
933 	next_packet |= rsv[0];
934 
935 	len = rsv[3];
936 	len <<= 8;
937 	len |= rsv[2];
938 
939 	rxstat = rsv[5];
940 	rxstat <<= 8;
941 	rxstat |= rsv[4];
942 
943 	if (netif_msg_rx_status(priv))
944 		enc28j60_dump_rsv(priv, __func__, next_packet, len, rxstat);
945 
946 	if (!RSV_GETBIT(rxstat, RSV_RXOK) || len > MAX_FRAMELEN) {
947 		if (netif_msg_rx_err(priv))
948 			dev_err(&ndev->dev, "Rx Error (%04x)\n", rxstat);
949 		ndev->stats.rx_errors++;
950 		if (RSV_GETBIT(rxstat, RSV_CRCERROR))
951 			ndev->stats.rx_crc_errors++;
952 		if (RSV_GETBIT(rxstat, RSV_LENCHECKERR))
953 			ndev->stats.rx_frame_errors++;
954 		if (len > MAX_FRAMELEN)
955 			ndev->stats.rx_over_errors++;
956 	} else {
957 		skb = netdev_alloc_skb(ndev, len + NET_IP_ALIGN);
958 		if (!skb) {
959 			if (netif_msg_rx_err(priv))
960 				dev_err(&ndev->dev,
961 					"out of memory for Rx'd frame\n");
962 			ndev->stats.rx_dropped++;
963 		} else {
964 			skb_reserve(skb, NET_IP_ALIGN);
965 			/* copy the packet from the receive buffer */
966 			enc28j60_mem_read(priv,
967 				rx_packet_start(priv->next_pk_ptr),
968 				len, skb_put(skb, len));
969 			if (netif_msg_pktdata(priv))
970 				dump_packet(__func__, skb->len, skb->data);
971 			skb->protocol = eth_type_trans(skb, ndev);
972 			/* update statistics */
973 			ndev->stats.rx_packets++;
974 			ndev->stats.rx_bytes += len;
975 			netif_rx_ni(skb);
976 		}
977 	}
978 	/*
979 	 * Move the RX read pointer to the start of the next
980 	 * received packet.
981 	 * This frees the memory we just read out
982 	 */
983 	erxrdpt = erxrdpt_workaround(next_packet, RXSTART_INIT, RXEND_INIT);
984 	if (netif_msg_hw(priv))
985 		printk(KERN_DEBUG DRV_NAME ": %s() ERXRDPT:0x%04x\n",
986 			__func__, erxrdpt);
987 
988 	mutex_lock(&priv->lock);
989 	nolock_regw_write(priv, ERXRDPTL, erxrdpt);
990 #ifdef CONFIG_ENC28J60_WRITEVERIFY
991 	if (netif_msg_drv(priv)) {
992 		u16 reg;
993 		reg = nolock_regw_read(priv, ERXRDPTL);
994 		if (reg != erxrdpt)
995 			printk(KERN_DEBUG DRV_NAME ": %s() ERXRDPT verify "
996 				"error (0x%04x - 0x%04x)\n", __func__,
997 				reg, erxrdpt);
998 	}
999 #endif
1000 	priv->next_pk_ptr = next_packet;
1001 	/* we are done with this packet, decrement the packet counter */
1002 	nolock_reg_bfset(priv, ECON2, ECON2_PKTDEC);
1003 	mutex_unlock(&priv->lock);
1004 }
1005 
1006 /*
1007  * Calculate free space in RxFIFO
1008  */
1009 static int enc28j60_get_free_rxfifo(struct enc28j60_net *priv)
1010 {
1011 	int epkcnt, erxst, erxnd, erxwr, erxrd;
1012 	int free_space;
1013 
1014 	mutex_lock(&priv->lock);
1015 	epkcnt = nolock_regb_read(priv, EPKTCNT);
1016 	if (epkcnt >= 255)
1017 		free_space = -1;
1018 	else {
1019 		erxst = nolock_regw_read(priv, ERXSTL);
1020 		erxnd = nolock_regw_read(priv, ERXNDL);
1021 		erxwr = nolock_regw_read(priv, ERXWRPTL);
1022 		erxrd = nolock_regw_read(priv, ERXRDPTL);
1023 
1024 		if (erxwr > erxrd)
1025 			free_space = (erxnd - erxst) - (erxwr - erxrd);
1026 		else if (erxwr == erxrd)
1027 			free_space = (erxnd - erxst);
1028 		else
1029 			free_space = erxrd - erxwr - 1;
1030 	}
1031 	mutex_unlock(&priv->lock);
1032 	if (netif_msg_rx_status(priv))
1033 		printk(KERN_DEBUG DRV_NAME ": %s() free_space = %d\n",
1034 			__func__, free_space);
1035 	return free_space;
1036 }
1037 
1038 /*
1039  * Access the PHY to determine link status
1040  */
1041 static void enc28j60_check_link_status(struct net_device *ndev)
1042 {
1043 	struct enc28j60_net *priv = netdev_priv(ndev);
1044 	u16 reg;
1045 	int duplex;
1046 
1047 	reg = enc28j60_phy_read(priv, PHSTAT2);
1048 	if (netif_msg_hw(priv))
1049 		printk(KERN_DEBUG DRV_NAME ": %s() PHSTAT1: %04x, "
1050 			"PHSTAT2: %04x\n", __func__,
1051 			enc28j60_phy_read(priv, PHSTAT1), reg);
1052 	duplex = reg & PHSTAT2_DPXSTAT;
1053 
1054 	if (reg & PHSTAT2_LSTAT) {
1055 		netif_carrier_on(ndev);
1056 		if (netif_msg_ifup(priv))
1057 			dev_info(&ndev->dev, "link up - %s\n",
1058 				duplex ? "Full duplex" : "Half duplex");
1059 	} else {
1060 		if (netif_msg_ifdown(priv))
1061 			dev_info(&ndev->dev, "link down\n");
1062 		netif_carrier_off(ndev);
1063 	}
1064 }
1065 
1066 static void enc28j60_tx_clear(struct net_device *ndev, bool err)
1067 {
1068 	struct enc28j60_net *priv = netdev_priv(ndev);
1069 
1070 	if (err)
1071 		ndev->stats.tx_errors++;
1072 	else
1073 		ndev->stats.tx_packets++;
1074 
1075 	if (priv->tx_skb) {
1076 		if (!err)
1077 			ndev->stats.tx_bytes += priv->tx_skb->len;
1078 		dev_kfree_skb(priv->tx_skb);
1079 		priv->tx_skb = NULL;
1080 	}
1081 	locked_reg_bfclr(priv, ECON1, ECON1_TXRTS);
1082 	netif_wake_queue(ndev);
1083 }
1084 
1085 /*
1086  * RX handler
1087  * ignore PKTIF because is unreliable! (look at the errata datasheet)
1088  * check EPKTCNT is the suggested workaround.
1089  * We don't need to clear interrupt flag, automatically done when
1090  * enc28j60_hw_rx() decrements the packet counter.
1091  * Returns how many packet processed.
1092  */
1093 static int enc28j60_rx_interrupt(struct net_device *ndev)
1094 {
1095 	struct enc28j60_net *priv = netdev_priv(ndev);
1096 	int pk_counter, ret;
1097 
1098 	pk_counter = locked_regb_read(priv, EPKTCNT);
1099 	if (pk_counter && netif_msg_intr(priv))
1100 		printk(KERN_DEBUG DRV_NAME ": intRX, pk_cnt: %d\n", pk_counter);
1101 	if (pk_counter > priv->max_pk_counter) {
1102 		/* update statistics */
1103 		priv->max_pk_counter = pk_counter;
1104 		if (netif_msg_rx_status(priv) && priv->max_pk_counter > 1)
1105 			printk(KERN_DEBUG DRV_NAME ": RX max_pk_cnt: %d\n",
1106 				priv->max_pk_counter);
1107 	}
1108 	ret = pk_counter;
1109 	while (pk_counter-- > 0)
1110 		enc28j60_hw_rx(ndev);
1111 
1112 	return ret;
1113 }
1114 
1115 static void enc28j60_irq_work_handler(struct work_struct *work)
1116 {
1117 	struct enc28j60_net *priv =
1118 		container_of(work, struct enc28j60_net, irq_work);
1119 	struct net_device *ndev = priv->netdev;
1120 	int intflags, loop;
1121 
1122 	if (netif_msg_intr(priv))
1123 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1124 	/* disable further interrupts */
1125 	locked_reg_bfclr(priv, EIE, EIE_INTIE);
1126 
1127 	do {
1128 		loop = 0;
1129 		intflags = locked_regb_read(priv, EIR);
1130 		/* DMA interrupt handler (not currently used) */
1131 		if ((intflags & EIR_DMAIF) != 0) {
1132 			loop++;
1133 			if (netif_msg_intr(priv))
1134 				printk(KERN_DEBUG DRV_NAME
1135 					": intDMA(%d)\n", loop);
1136 			locked_reg_bfclr(priv, EIR, EIR_DMAIF);
1137 		}
1138 		/* LINK changed handler */
1139 		if ((intflags & EIR_LINKIF) != 0) {
1140 			loop++;
1141 			if (netif_msg_intr(priv))
1142 				printk(KERN_DEBUG DRV_NAME
1143 					": intLINK(%d)\n", loop);
1144 			enc28j60_check_link_status(ndev);
1145 			/* read PHIR to clear the flag */
1146 			enc28j60_phy_read(priv, PHIR);
1147 		}
1148 		/* TX complete handler */
1149 		if ((intflags & EIR_TXIF) != 0) {
1150 			bool err = false;
1151 			loop++;
1152 			if (netif_msg_intr(priv))
1153 				printk(KERN_DEBUG DRV_NAME
1154 					": intTX(%d)\n", loop);
1155 			priv->tx_retry_count = 0;
1156 			if (locked_regb_read(priv, ESTAT) & ESTAT_TXABRT) {
1157 				if (netif_msg_tx_err(priv))
1158 					dev_err(&ndev->dev,
1159 						"Tx Error (aborted)\n");
1160 				err = true;
1161 			}
1162 			if (netif_msg_tx_done(priv)) {
1163 				u8 tsv[TSV_SIZE];
1164 				enc28j60_read_tsv(priv, tsv);
1165 				enc28j60_dump_tsv(priv, "Tx Done", tsv);
1166 			}
1167 			enc28j60_tx_clear(ndev, err);
1168 			locked_reg_bfclr(priv, EIR, EIR_TXIF);
1169 		}
1170 		/* TX Error handler */
1171 		if ((intflags & EIR_TXERIF) != 0) {
1172 			u8 tsv[TSV_SIZE];
1173 
1174 			loop++;
1175 			if (netif_msg_intr(priv))
1176 				printk(KERN_DEBUG DRV_NAME
1177 					": intTXErr(%d)\n", loop);
1178 			locked_reg_bfclr(priv, ECON1, ECON1_TXRTS);
1179 			enc28j60_read_tsv(priv, tsv);
1180 			if (netif_msg_tx_err(priv))
1181 				enc28j60_dump_tsv(priv, "Tx Error", tsv);
1182 			/* Reset TX logic */
1183 			mutex_lock(&priv->lock);
1184 			nolock_reg_bfset(priv, ECON1, ECON1_TXRST);
1185 			nolock_reg_bfclr(priv, ECON1, ECON1_TXRST);
1186 			nolock_txfifo_init(priv, TXSTART_INIT, TXEND_INIT);
1187 			mutex_unlock(&priv->lock);
1188 			/* Transmit Late collision check for retransmit */
1189 			if (TSV_GETBIT(tsv, TSV_TXLATECOLLISION)) {
1190 				if (netif_msg_tx_err(priv))
1191 					printk(KERN_DEBUG DRV_NAME
1192 						": LateCollision TXErr (%d)\n",
1193 						priv->tx_retry_count);
1194 				if (priv->tx_retry_count++ < MAX_TX_RETRYCOUNT)
1195 					locked_reg_bfset(priv, ECON1,
1196 							   ECON1_TXRTS);
1197 				else
1198 					enc28j60_tx_clear(ndev, true);
1199 			} else
1200 				enc28j60_tx_clear(ndev, true);
1201 			locked_reg_bfclr(priv, EIR, EIR_TXERIF);
1202 		}
1203 		/* RX Error handler */
1204 		if ((intflags & EIR_RXERIF) != 0) {
1205 			loop++;
1206 			if (netif_msg_intr(priv))
1207 				printk(KERN_DEBUG DRV_NAME
1208 					": intRXErr(%d)\n", loop);
1209 			/* Check free FIFO space to flag RX overrun */
1210 			if (enc28j60_get_free_rxfifo(priv) <= 0) {
1211 				if (netif_msg_rx_err(priv))
1212 					printk(KERN_DEBUG DRV_NAME
1213 						": RX Overrun\n");
1214 				ndev->stats.rx_dropped++;
1215 			}
1216 			locked_reg_bfclr(priv, EIR, EIR_RXERIF);
1217 		}
1218 		/* RX handler */
1219 		if (enc28j60_rx_interrupt(ndev))
1220 			loop++;
1221 	} while (loop);
1222 
1223 	/* re-enable interrupts */
1224 	locked_reg_bfset(priv, EIE, EIE_INTIE);
1225 	if (netif_msg_intr(priv))
1226 		printk(KERN_DEBUG DRV_NAME ": %s() exit\n", __func__);
1227 }
1228 
1229 /*
1230  * Hardware transmit function.
1231  * Fill the buffer memory and send the contents of the transmit buffer
1232  * onto the network
1233  */
1234 static void enc28j60_hw_tx(struct enc28j60_net *priv)
1235 {
1236 	if (netif_msg_tx_queued(priv))
1237 		printk(KERN_DEBUG DRV_NAME
1238 			": Tx Packet Len:%d\n", priv->tx_skb->len);
1239 
1240 	if (netif_msg_pktdata(priv))
1241 		dump_packet(__func__,
1242 			    priv->tx_skb->len, priv->tx_skb->data);
1243 	enc28j60_packet_write(priv, priv->tx_skb->len, priv->tx_skb->data);
1244 
1245 #ifdef CONFIG_ENC28J60_WRITEVERIFY
1246 	/* readback and verify written data */
1247 	if (netif_msg_drv(priv)) {
1248 		int test_len, k;
1249 		u8 test_buf[64]; /* limit the test to the first 64 bytes */
1250 		int okflag;
1251 
1252 		test_len = priv->tx_skb->len;
1253 		if (test_len > sizeof(test_buf))
1254 			test_len = sizeof(test_buf);
1255 
1256 		/* + 1 to skip control byte */
1257 		enc28j60_mem_read(priv, TXSTART_INIT + 1, test_len, test_buf);
1258 		okflag = 1;
1259 		for (k = 0; k < test_len; k++) {
1260 			if (priv->tx_skb->data[k] != test_buf[k]) {
1261 				printk(KERN_DEBUG DRV_NAME
1262 					 ": Error, %d location differ: "
1263 					 "0x%02x-0x%02x\n", k,
1264 					 priv->tx_skb->data[k], test_buf[k]);
1265 				okflag = 0;
1266 			}
1267 		}
1268 		if (!okflag)
1269 			printk(KERN_DEBUG DRV_NAME ": Tx write buffer, "
1270 				"verify ERROR!\n");
1271 	}
1272 #endif
1273 	/* set TX request flag */
1274 	locked_reg_bfset(priv, ECON1, ECON1_TXRTS);
1275 }
1276 
1277 static netdev_tx_t enc28j60_send_packet(struct sk_buff *skb,
1278 					struct net_device *dev)
1279 {
1280 	struct enc28j60_net *priv = netdev_priv(dev);
1281 
1282 	if (netif_msg_tx_queued(priv))
1283 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1284 
1285 	/* If some error occurs while trying to transmit this
1286 	 * packet, you should return '1' from this function.
1287 	 * In such a case you _may not_ do anything to the
1288 	 * SKB, it is still owned by the network queueing
1289 	 * layer when an error is returned.  This means you
1290 	 * may not modify any SKB fields, you may not free
1291 	 * the SKB, etc.
1292 	 */
1293 	netif_stop_queue(dev);
1294 
1295 	/* Remember the skb for deferred processing */
1296 	priv->tx_skb = skb;
1297 	schedule_work(&priv->tx_work);
1298 
1299 	return NETDEV_TX_OK;
1300 }
1301 
1302 static void enc28j60_tx_work_handler(struct work_struct *work)
1303 {
1304 	struct enc28j60_net *priv =
1305 		container_of(work, struct enc28j60_net, tx_work);
1306 
1307 	/* actual delivery of data */
1308 	enc28j60_hw_tx(priv);
1309 }
1310 
1311 static irqreturn_t enc28j60_irq(int irq, void *dev_id)
1312 {
1313 	struct enc28j60_net *priv = dev_id;
1314 
1315 	/*
1316 	 * Can't do anything in interrupt context because we need to
1317 	 * block (spi_sync() is blocking) so fire of the interrupt
1318 	 * handling workqueue.
1319 	 * Remember that we access enc28j60 registers through SPI bus
1320 	 * via spi_sync() call.
1321 	 */
1322 	schedule_work(&priv->irq_work);
1323 
1324 	return IRQ_HANDLED;
1325 }
1326 
1327 static void enc28j60_tx_timeout(struct net_device *ndev)
1328 {
1329 	struct enc28j60_net *priv = netdev_priv(ndev);
1330 
1331 	if (netif_msg_timer(priv))
1332 		dev_err(&ndev->dev, DRV_NAME " tx timeout\n");
1333 
1334 	ndev->stats.tx_errors++;
1335 	/* can't restart safely under softirq */
1336 	schedule_work(&priv->restart_work);
1337 }
1338 
1339 /*
1340  * Open/initialize the board. This is called (in the current kernel)
1341  * sometime after booting when the 'ifconfig' program is run.
1342  *
1343  * This routine should set everything up anew at each open, even
1344  * registers that "should" only need to be set once at boot, so that
1345  * there is non-reboot way to recover if something goes wrong.
1346  */
1347 static int enc28j60_net_open(struct net_device *dev)
1348 {
1349 	struct enc28j60_net *priv = netdev_priv(dev);
1350 
1351 	if (netif_msg_drv(priv))
1352 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1353 
1354 	if (!is_valid_ether_addr(dev->dev_addr)) {
1355 		if (netif_msg_ifup(priv))
1356 			dev_err(&dev->dev, "invalid MAC address %pM\n",
1357 				dev->dev_addr);
1358 		return -EADDRNOTAVAIL;
1359 	}
1360 	/* Reset the hardware here (and take it out of low power mode) */
1361 	enc28j60_lowpower(priv, false);
1362 	enc28j60_hw_disable(priv);
1363 	if (!enc28j60_hw_init(priv)) {
1364 		if (netif_msg_ifup(priv))
1365 			dev_err(&dev->dev, "hw_reset() failed\n");
1366 		return -EINVAL;
1367 	}
1368 	/* Update the MAC address (in case user has changed it) */
1369 	enc28j60_set_hw_macaddr(dev);
1370 	/* Enable interrupts */
1371 	enc28j60_hw_enable(priv);
1372 	/* check link status */
1373 	enc28j60_check_link_status(dev);
1374 	/* We are now ready to accept transmit requests from
1375 	 * the queueing layer of the networking.
1376 	 */
1377 	netif_start_queue(dev);
1378 
1379 	return 0;
1380 }
1381 
1382 /* The inverse routine to net_open(). */
1383 static int enc28j60_net_close(struct net_device *dev)
1384 {
1385 	struct enc28j60_net *priv = netdev_priv(dev);
1386 
1387 	if (netif_msg_drv(priv))
1388 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1389 
1390 	enc28j60_hw_disable(priv);
1391 	enc28j60_lowpower(priv, true);
1392 	netif_stop_queue(dev);
1393 
1394 	return 0;
1395 }
1396 
1397 /*
1398  * Set or clear the multicast filter for this adapter
1399  * num_addrs == -1	Promiscuous mode, receive all packets
1400  * num_addrs == 0	Normal mode, filter out multicast packets
1401  * num_addrs > 0	Multicast mode, receive normal and MC packets
1402  */
1403 static void enc28j60_set_multicast_list(struct net_device *dev)
1404 {
1405 	struct enc28j60_net *priv = netdev_priv(dev);
1406 	int oldfilter = priv->rxfilter;
1407 
1408 	if (dev->flags & IFF_PROMISC) {
1409 		if (netif_msg_link(priv))
1410 			dev_info(&dev->dev, "promiscuous mode\n");
1411 		priv->rxfilter = RXFILTER_PROMISC;
1412 	} else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev)) {
1413 		if (netif_msg_link(priv))
1414 			dev_info(&dev->dev, "%smulticast mode\n",
1415 				(dev->flags & IFF_ALLMULTI) ? "all-" : "");
1416 		priv->rxfilter = RXFILTER_MULTI;
1417 	} else {
1418 		if (netif_msg_link(priv))
1419 			dev_info(&dev->dev, "normal mode\n");
1420 		priv->rxfilter = RXFILTER_NORMAL;
1421 	}
1422 
1423 	if (oldfilter != priv->rxfilter)
1424 		schedule_work(&priv->setrx_work);
1425 }
1426 
1427 static void enc28j60_setrx_work_handler(struct work_struct *work)
1428 {
1429 	struct enc28j60_net *priv =
1430 		container_of(work, struct enc28j60_net, setrx_work);
1431 
1432 	if (priv->rxfilter == RXFILTER_PROMISC) {
1433 		if (netif_msg_drv(priv))
1434 			printk(KERN_DEBUG DRV_NAME ": promiscuous mode\n");
1435 		locked_regb_write(priv, ERXFCON, 0x00);
1436 	} else if (priv->rxfilter == RXFILTER_MULTI) {
1437 		if (netif_msg_drv(priv))
1438 			printk(KERN_DEBUG DRV_NAME ": multicast mode\n");
1439 		locked_regb_write(priv, ERXFCON,
1440 					ERXFCON_UCEN | ERXFCON_CRCEN |
1441 					ERXFCON_BCEN | ERXFCON_MCEN);
1442 	} else {
1443 		if (netif_msg_drv(priv))
1444 			printk(KERN_DEBUG DRV_NAME ": normal mode\n");
1445 		locked_regb_write(priv, ERXFCON,
1446 					ERXFCON_UCEN | ERXFCON_CRCEN |
1447 					ERXFCON_BCEN);
1448 	}
1449 }
1450 
1451 static void enc28j60_restart_work_handler(struct work_struct *work)
1452 {
1453 	struct enc28j60_net *priv =
1454 			container_of(work, struct enc28j60_net, restart_work);
1455 	struct net_device *ndev = priv->netdev;
1456 	int ret;
1457 
1458 	rtnl_lock();
1459 	if (netif_running(ndev)) {
1460 		enc28j60_net_close(ndev);
1461 		ret = enc28j60_net_open(ndev);
1462 		if (unlikely(ret)) {
1463 			dev_info(&ndev->dev, " could not restart %d\n", ret);
1464 			dev_close(ndev);
1465 		}
1466 	}
1467 	rtnl_unlock();
1468 }
1469 
1470 /* ......................... ETHTOOL SUPPORT ........................... */
1471 
1472 static void
1473 enc28j60_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1474 {
1475 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1476 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1477 	strlcpy(info->bus_info,
1478 		dev_name(dev->dev.parent), sizeof(info->bus_info));
1479 }
1480 
1481 static int
1482 enc28j60_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1483 {
1484 	struct enc28j60_net *priv = netdev_priv(dev);
1485 
1486 	cmd->transceiver = XCVR_INTERNAL;
1487 	cmd->supported	= SUPPORTED_10baseT_Half
1488 			| SUPPORTED_10baseT_Full
1489 			| SUPPORTED_TP;
1490 	ethtool_cmd_speed_set(cmd,  SPEED_10);
1491 	cmd->duplex	= priv->full_duplex ? DUPLEX_FULL : DUPLEX_HALF;
1492 	cmd->port	= PORT_TP;
1493 	cmd->autoneg	= AUTONEG_DISABLE;
1494 
1495 	return 0;
1496 }
1497 
1498 static int
1499 enc28j60_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1500 {
1501 	return enc28j60_setlink(dev, cmd->autoneg,
1502 				ethtool_cmd_speed(cmd), cmd->duplex);
1503 }
1504 
1505 static u32 enc28j60_get_msglevel(struct net_device *dev)
1506 {
1507 	struct enc28j60_net *priv = netdev_priv(dev);
1508 	return priv->msg_enable;
1509 }
1510 
1511 static void enc28j60_set_msglevel(struct net_device *dev, u32 val)
1512 {
1513 	struct enc28j60_net *priv = netdev_priv(dev);
1514 	priv->msg_enable = val;
1515 }
1516 
1517 static const struct ethtool_ops enc28j60_ethtool_ops = {
1518 	.get_settings	= enc28j60_get_settings,
1519 	.set_settings	= enc28j60_set_settings,
1520 	.get_drvinfo	= enc28j60_get_drvinfo,
1521 	.get_msglevel	= enc28j60_get_msglevel,
1522 	.set_msglevel	= enc28j60_set_msglevel,
1523 };
1524 
1525 static int enc28j60_chipset_init(struct net_device *dev)
1526 {
1527 	struct enc28j60_net *priv = netdev_priv(dev);
1528 
1529 	return enc28j60_hw_init(priv);
1530 }
1531 
1532 static const struct net_device_ops enc28j60_netdev_ops = {
1533 	.ndo_open		= enc28j60_net_open,
1534 	.ndo_stop		= enc28j60_net_close,
1535 	.ndo_start_xmit		= enc28j60_send_packet,
1536 	.ndo_set_rx_mode	= enc28j60_set_multicast_list,
1537 	.ndo_set_mac_address	= enc28j60_set_mac_address,
1538 	.ndo_tx_timeout		= enc28j60_tx_timeout,
1539 	.ndo_change_mtu		= eth_change_mtu,
1540 	.ndo_validate_addr	= eth_validate_addr,
1541 };
1542 
1543 static int enc28j60_probe(struct spi_device *spi)
1544 {
1545 	struct net_device *dev;
1546 	struct enc28j60_net *priv;
1547 	int ret = 0;
1548 
1549 	if (netif_msg_drv(&debug))
1550 		dev_info(&spi->dev, DRV_NAME " Ethernet driver %s loaded\n",
1551 			DRV_VERSION);
1552 
1553 	dev = alloc_etherdev(sizeof(struct enc28j60_net));
1554 	if (!dev) {
1555 		ret = -ENOMEM;
1556 		goto error_alloc;
1557 	}
1558 	priv = netdev_priv(dev);
1559 
1560 	priv->netdev = dev;	/* priv to netdev reference */
1561 	priv->spi = spi;	/* priv to spi reference */
1562 	priv->msg_enable = netif_msg_init(debug.msg_enable,
1563 						ENC28J60_MSG_DEFAULT);
1564 	mutex_init(&priv->lock);
1565 	INIT_WORK(&priv->tx_work, enc28j60_tx_work_handler);
1566 	INIT_WORK(&priv->setrx_work, enc28j60_setrx_work_handler);
1567 	INIT_WORK(&priv->irq_work, enc28j60_irq_work_handler);
1568 	INIT_WORK(&priv->restart_work, enc28j60_restart_work_handler);
1569 	spi_set_drvdata(spi, priv);	/* spi to priv reference */
1570 	SET_NETDEV_DEV(dev, &spi->dev);
1571 
1572 	if (!enc28j60_chipset_init(dev)) {
1573 		if (netif_msg_probe(priv))
1574 			dev_info(&spi->dev, DRV_NAME " chip not found\n");
1575 		ret = -EIO;
1576 		goto error_irq;
1577 	}
1578 	eth_hw_addr_random(dev);
1579 	enc28j60_set_hw_macaddr(dev);
1580 
1581 	/* Board setup must set the relevant edge trigger type;
1582 	 * level triggers won't currently work.
1583 	 */
1584 	ret = request_irq(spi->irq, enc28j60_irq, 0, DRV_NAME, priv);
1585 	if (ret < 0) {
1586 		if (netif_msg_probe(priv))
1587 			dev_err(&spi->dev, DRV_NAME ": request irq %d failed "
1588 				"(ret = %d)\n", spi->irq, ret);
1589 		goto error_irq;
1590 	}
1591 
1592 	dev->if_port = IF_PORT_10BASET;
1593 	dev->irq = spi->irq;
1594 	dev->netdev_ops = &enc28j60_netdev_ops;
1595 	dev->watchdog_timeo = TX_TIMEOUT;
1596 	dev->ethtool_ops = &enc28j60_ethtool_ops;
1597 
1598 	enc28j60_lowpower(priv, true);
1599 
1600 	ret = register_netdev(dev);
1601 	if (ret) {
1602 		if (netif_msg_probe(priv))
1603 			dev_err(&spi->dev, "register netdev " DRV_NAME
1604 				" failed (ret = %d)\n", ret);
1605 		goto error_register;
1606 	}
1607 	dev_info(&dev->dev, DRV_NAME " driver registered\n");
1608 
1609 	return 0;
1610 
1611 error_register:
1612 	free_irq(spi->irq, priv);
1613 error_irq:
1614 	free_netdev(dev);
1615 error_alloc:
1616 	return ret;
1617 }
1618 
1619 static int enc28j60_remove(struct spi_device *spi)
1620 {
1621 	struct enc28j60_net *priv = spi_get_drvdata(spi);
1622 
1623 	if (netif_msg_drv(priv))
1624 		printk(KERN_DEBUG DRV_NAME ": remove\n");
1625 
1626 	unregister_netdev(priv->netdev);
1627 	free_irq(spi->irq, priv);
1628 	free_netdev(priv->netdev);
1629 
1630 	return 0;
1631 }
1632 
1633 static struct spi_driver enc28j60_driver = {
1634 	.driver = {
1635 		   .name = DRV_NAME,
1636 	 },
1637 	.probe = enc28j60_probe,
1638 	.remove = enc28j60_remove,
1639 };
1640 
1641 static int __init enc28j60_init(void)
1642 {
1643 	msec20_to_jiffies = msecs_to_jiffies(20);
1644 
1645 	return spi_register_driver(&enc28j60_driver);
1646 }
1647 
1648 module_init(enc28j60_init);
1649 
1650 static void __exit enc28j60_exit(void)
1651 {
1652 	spi_unregister_driver(&enc28j60_driver);
1653 }
1654 
1655 module_exit(enc28j60_exit);
1656 
1657 MODULE_DESCRIPTION(DRV_NAME " ethernet driver");
1658 MODULE_AUTHOR("Claudio Lanconelli <lanconelli.claudio@eptar.com>");
1659 MODULE_LICENSE("GPL");
1660 module_param_named(debug, debug.msg_enable, int, 0);
1661 MODULE_PARM_DESC(debug, "Debug verbosity level (0=none, ..., ffff=all)");
1662 MODULE_ALIAS("spi:" DRV_NAME);
1663