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 	dev->addr_assign_type &= ~NET_ADDR_RANDOM;
531 	memcpy(dev->dev_addr, address->sa_data, dev->addr_len);
532 	return enc28j60_set_hw_macaddr(dev);
533 }
534 
535 /*
536  * Debug routine to dump useful register contents
537  */
538 static void enc28j60_dump_regs(struct enc28j60_net *priv, const char *msg)
539 {
540 	mutex_lock(&priv->lock);
541 	printk(KERN_DEBUG DRV_NAME " %s\n"
542 		"HwRevID: 0x%02x\n"
543 		"Cntrl: ECON1 ECON2 ESTAT  EIR  EIE\n"
544 		"       0x%02x  0x%02x  0x%02x  0x%02x  0x%02x\n"
545 		"MAC  : MACON1 MACON3 MACON4\n"
546 		"       0x%02x   0x%02x   0x%02x\n"
547 		"Rx   : ERXST  ERXND  ERXWRPT ERXRDPT ERXFCON EPKTCNT MAMXFL\n"
548 		"       0x%04x 0x%04x 0x%04x  0x%04x  "
549 		"0x%02x    0x%02x    0x%04x\n"
550 		"Tx   : ETXST  ETXND  MACLCON1 MACLCON2 MAPHSUP\n"
551 		"       0x%04x 0x%04x 0x%02x     0x%02x     0x%02x\n",
552 		msg, nolock_regb_read(priv, EREVID),
553 		nolock_regb_read(priv, ECON1), nolock_regb_read(priv, ECON2),
554 		nolock_regb_read(priv, ESTAT), nolock_regb_read(priv, EIR),
555 		nolock_regb_read(priv, EIE), nolock_regb_read(priv, MACON1),
556 		nolock_regb_read(priv, MACON3), nolock_regb_read(priv, MACON4),
557 		nolock_regw_read(priv, ERXSTL), nolock_regw_read(priv, ERXNDL),
558 		nolock_regw_read(priv, ERXWRPTL),
559 		nolock_regw_read(priv, ERXRDPTL),
560 		nolock_regb_read(priv, ERXFCON),
561 		nolock_regb_read(priv, EPKTCNT),
562 		nolock_regw_read(priv, MAMXFLL), nolock_regw_read(priv, ETXSTL),
563 		nolock_regw_read(priv, ETXNDL),
564 		nolock_regb_read(priv, MACLCON1),
565 		nolock_regb_read(priv, MACLCON2),
566 		nolock_regb_read(priv, MAPHSUP));
567 	mutex_unlock(&priv->lock);
568 }
569 
570 /*
571  * ERXRDPT need to be set always at odd addresses, refer to errata datasheet
572  */
573 static u16 erxrdpt_workaround(u16 next_packet_ptr, u16 start, u16 end)
574 {
575 	u16 erxrdpt;
576 
577 	if ((next_packet_ptr - 1 < start) || (next_packet_ptr - 1 > end))
578 		erxrdpt = end;
579 	else
580 		erxrdpt = next_packet_ptr - 1;
581 
582 	return erxrdpt;
583 }
584 
585 /*
586  * Calculate wrap around when reading beyond the end of the RX buffer
587  */
588 static u16 rx_packet_start(u16 ptr)
589 {
590 	if (ptr + RSV_SIZE > RXEND_INIT)
591 		return (ptr + RSV_SIZE) - (RXEND_INIT - RXSTART_INIT + 1);
592 	else
593 		return ptr + RSV_SIZE;
594 }
595 
596 static void nolock_rxfifo_init(struct enc28j60_net *priv, u16 start, u16 end)
597 {
598 	u16 erxrdpt;
599 
600 	if (start > 0x1FFF || end > 0x1FFF || start > end) {
601 		if (netif_msg_drv(priv))
602 			printk(KERN_ERR DRV_NAME ": %s(%d, %d) RXFIFO "
603 				"bad parameters!\n", __func__, start, end);
604 		return;
605 	}
606 	/* set receive buffer start + end */
607 	priv->next_pk_ptr = start;
608 	nolock_regw_write(priv, ERXSTL, start);
609 	erxrdpt = erxrdpt_workaround(priv->next_pk_ptr, start, end);
610 	nolock_regw_write(priv, ERXRDPTL, erxrdpt);
611 	nolock_regw_write(priv, ERXNDL, end);
612 }
613 
614 static void nolock_txfifo_init(struct enc28j60_net *priv, u16 start, u16 end)
615 {
616 	if (start > 0x1FFF || end > 0x1FFF || start > end) {
617 		if (netif_msg_drv(priv))
618 			printk(KERN_ERR DRV_NAME ": %s(%d, %d) TXFIFO "
619 				"bad parameters!\n", __func__, start, end);
620 		return;
621 	}
622 	/* set transmit buffer start + end */
623 	nolock_regw_write(priv, ETXSTL, start);
624 	nolock_regw_write(priv, ETXNDL, end);
625 }
626 
627 /*
628  * Low power mode shrinks power consumption about 100x, so we'd like
629  * the chip to be in that mode whenever it's inactive.  (However, we
630  * can't stay in lowpower mode during suspend with WOL active.)
631  */
632 static void enc28j60_lowpower(struct enc28j60_net *priv, bool is_low)
633 {
634 	if (netif_msg_drv(priv))
635 		dev_dbg(&priv->spi->dev, "%s power...\n",
636 				is_low ? "low" : "high");
637 
638 	mutex_lock(&priv->lock);
639 	if (is_low) {
640 		nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
641 		poll_ready(priv, ESTAT, ESTAT_RXBUSY, 0);
642 		poll_ready(priv, ECON1, ECON1_TXRTS, 0);
643 		/* ECON2_VRPS was set during initialization */
644 		nolock_reg_bfset(priv, ECON2, ECON2_PWRSV);
645 	} else {
646 		nolock_reg_bfclr(priv, ECON2, ECON2_PWRSV);
647 		poll_ready(priv, ESTAT, ESTAT_CLKRDY, ESTAT_CLKRDY);
648 		/* caller sets ECON1_RXEN */
649 	}
650 	mutex_unlock(&priv->lock);
651 }
652 
653 static int enc28j60_hw_init(struct enc28j60_net *priv)
654 {
655 	u8 reg;
656 
657 	if (netif_msg_drv(priv))
658 		printk(KERN_DEBUG DRV_NAME ": %s() - %s\n", __func__,
659 			priv->full_duplex ? "FullDuplex" : "HalfDuplex");
660 
661 	mutex_lock(&priv->lock);
662 	/* first reset the chip */
663 	enc28j60_soft_reset(priv);
664 	/* Clear ECON1 */
665 	spi_write_op(priv, ENC28J60_WRITE_CTRL_REG, ECON1, 0x00);
666 	priv->bank = 0;
667 	priv->hw_enable = false;
668 	priv->tx_retry_count = 0;
669 	priv->max_pk_counter = 0;
670 	priv->rxfilter = RXFILTER_NORMAL;
671 	/* enable address auto increment and voltage regulator powersave */
672 	nolock_regb_write(priv, ECON2, ECON2_AUTOINC | ECON2_VRPS);
673 
674 	nolock_rxfifo_init(priv, RXSTART_INIT, RXEND_INIT);
675 	nolock_txfifo_init(priv, TXSTART_INIT, TXEND_INIT);
676 	mutex_unlock(&priv->lock);
677 
678 	/*
679 	 * Check the RevID.
680 	 * If it's 0x00 or 0xFF probably the enc28j60 is not mounted or
681 	 * damaged
682 	 */
683 	reg = locked_regb_read(priv, EREVID);
684 	if (netif_msg_drv(priv))
685 		printk(KERN_INFO DRV_NAME ": chip RevID: 0x%02x\n", reg);
686 	if (reg == 0x00 || reg == 0xff) {
687 		if (netif_msg_drv(priv))
688 			printk(KERN_DEBUG DRV_NAME ": %s() Invalid RevId %d\n",
689 				__func__, reg);
690 		return 0;
691 	}
692 
693 	/* default filter mode: (unicast OR broadcast) AND crc valid */
694 	locked_regb_write(priv, ERXFCON,
695 			    ERXFCON_UCEN | ERXFCON_CRCEN | ERXFCON_BCEN);
696 
697 	/* enable MAC receive */
698 	locked_regb_write(priv, MACON1,
699 			    MACON1_MARXEN | MACON1_TXPAUS | MACON1_RXPAUS);
700 	/* enable automatic padding and CRC operations */
701 	if (priv->full_duplex) {
702 		locked_regb_write(priv, MACON3,
703 				    MACON3_PADCFG0 | MACON3_TXCRCEN |
704 				    MACON3_FRMLNEN | MACON3_FULDPX);
705 		/* set inter-frame gap (non-back-to-back) */
706 		locked_regb_write(priv, MAIPGL, 0x12);
707 		/* set inter-frame gap (back-to-back) */
708 		locked_regb_write(priv, MABBIPG, 0x15);
709 	} else {
710 		locked_regb_write(priv, MACON3,
711 				    MACON3_PADCFG0 | MACON3_TXCRCEN |
712 				    MACON3_FRMLNEN);
713 		locked_regb_write(priv, MACON4, 1 << 6);	/* DEFER bit */
714 		/* set inter-frame gap (non-back-to-back) */
715 		locked_regw_write(priv, MAIPGL, 0x0C12);
716 		/* set inter-frame gap (back-to-back) */
717 		locked_regb_write(priv, MABBIPG, 0x12);
718 	}
719 	/*
720 	 * MACLCON1 (default)
721 	 * MACLCON2 (default)
722 	 * Set the maximum packet size which the controller will accept
723 	 */
724 	locked_regw_write(priv, MAMXFLL, MAX_FRAMELEN);
725 
726 	/* Configure LEDs */
727 	if (!enc28j60_phy_write(priv, PHLCON, ENC28J60_LAMPS_MODE))
728 		return 0;
729 
730 	if (priv->full_duplex) {
731 		if (!enc28j60_phy_write(priv, PHCON1, PHCON1_PDPXMD))
732 			return 0;
733 		if (!enc28j60_phy_write(priv, PHCON2, 0x00))
734 			return 0;
735 	} else {
736 		if (!enc28j60_phy_write(priv, PHCON1, 0x00))
737 			return 0;
738 		if (!enc28j60_phy_write(priv, PHCON2, PHCON2_HDLDIS))
739 			return 0;
740 	}
741 	if (netif_msg_hw(priv))
742 		enc28j60_dump_regs(priv, "Hw initialized.");
743 
744 	return 1;
745 }
746 
747 static void enc28j60_hw_enable(struct enc28j60_net *priv)
748 {
749 	/* enable interrupts */
750 	if (netif_msg_hw(priv))
751 		printk(KERN_DEBUG DRV_NAME ": %s() enabling interrupts.\n",
752 			__func__);
753 
754 	enc28j60_phy_write(priv, PHIE, PHIE_PGEIE | PHIE_PLNKIE);
755 
756 	mutex_lock(&priv->lock);
757 	nolock_reg_bfclr(priv, EIR, EIR_DMAIF | EIR_LINKIF |
758 			 EIR_TXIF | EIR_TXERIF | EIR_RXERIF | EIR_PKTIF);
759 	nolock_regb_write(priv, EIE, EIE_INTIE | EIE_PKTIE | EIE_LINKIE |
760 			  EIE_TXIE | EIE_TXERIE | EIE_RXERIE);
761 
762 	/* enable receive logic */
763 	nolock_reg_bfset(priv, ECON1, ECON1_RXEN);
764 	priv->hw_enable = true;
765 	mutex_unlock(&priv->lock);
766 }
767 
768 static void enc28j60_hw_disable(struct enc28j60_net *priv)
769 {
770 	mutex_lock(&priv->lock);
771 	/* disable interrutps and packet reception */
772 	nolock_regb_write(priv, EIE, 0x00);
773 	nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
774 	priv->hw_enable = false;
775 	mutex_unlock(&priv->lock);
776 }
777 
778 static int
779 enc28j60_setlink(struct net_device *ndev, u8 autoneg, u16 speed, u8 duplex)
780 {
781 	struct enc28j60_net *priv = netdev_priv(ndev);
782 	int ret = 0;
783 
784 	if (!priv->hw_enable) {
785 		/* link is in low power mode now; duplex setting
786 		 * will take effect on next enc28j60_hw_init().
787 		 */
788 		if (autoneg == AUTONEG_DISABLE && speed == SPEED_10)
789 			priv->full_duplex = (duplex == DUPLEX_FULL);
790 		else {
791 			if (netif_msg_link(priv))
792 				dev_warn(&ndev->dev,
793 					"unsupported link setting\n");
794 			ret = -EOPNOTSUPP;
795 		}
796 	} else {
797 		if (netif_msg_link(priv))
798 			dev_warn(&ndev->dev, "Warning: hw must be disabled "
799 				"to set link mode\n");
800 		ret = -EBUSY;
801 	}
802 	return ret;
803 }
804 
805 /*
806  * Read the Transmit Status Vector
807  */
808 static void enc28j60_read_tsv(struct enc28j60_net *priv, u8 tsv[TSV_SIZE])
809 {
810 	int endptr;
811 
812 	endptr = locked_regw_read(priv, ETXNDL);
813 	if (netif_msg_hw(priv))
814 		printk(KERN_DEBUG DRV_NAME ": reading TSV at addr:0x%04x\n",
815 			 endptr + 1);
816 	enc28j60_mem_read(priv, endptr + 1, TSV_SIZE, tsv);
817 }
818 
819 static void enc28j60_dump_tsv(struct enc28j60_net *priv, const char *msg,
820 				u8 tsv[TSV_SIZE])
821 {
822 	u16 tmp1, tmp2;
823 
824 	printk(KERN_DEBUG DRV_NAME ": %s - TSV:\n", msg);
825 	tmp1 = tsv[1];
826 	tmp1 <<= 8;
827 	tmp1 |= tsv[0];
828 
829 	tmp2 = tsv[5];
830 	tmp2 <<= 8;
831 	tmp2 |= tsv[4];
832 
833 	printk(KERN_DEBUG DRV_NAME ": ByteCount: %d, CollisionCount: %d,"
834 		" TotByteOnWire: %d\n", tmp1, tsv[2] & 0x0f, tmp2);
835 	printk(KERN_DEBUG DRV_NAME ": TxDone: %d, CRCErr:%d, LenChkErr: %d,"
836 		" LenOutOfRange: %d\n", TSV_GETBIT(tsv, TSV_TXDONE),
837 		TSV_GETBIT(tsv, TSV_TXCRCERROR),
838 		TSV_GETBIT(tsv, TSV_TXLENCHKERROR),
839 		TSV_GETBIT(tsv, TSV_TXLENOUTOFRANGE));
840 	printk(KERN_DEBUG DRV_NAME ": Multicast: %d, Broadcast: %d, "
841 		"PacketDefer: %d, ExDefer: %d\n",
842 		TSV_GETBIT(tsv, TSV_TXMULTICAST),
843 		TSV_GETBIT(tsv, TSV_TXBROADCAST),
844 		TSV_GETBIT(tsv, TSV_TXPACKETDEFER),
845 		TSV_GETBIT(tsv, TSV_TXEXDEFER));
846 	printk(KERN_DEBUG DRV_NAME ": ExCollision: %d, LateCollision: %d, "
847 		 "Giant: %d, Underrun: %d\n",
848 		 TSV_GETBIT(tsv, TSV_TXEXCOLLISION),
849 		 TSV_GETBIT(tsv, TSV_TXLATECOLLISION),
850 		 TSV_GETBIT(tsv, TSV_TXGIANT), TSV_GETBIT(tsv, TSV_TXUNDERRUN));
851 	printk(KERN_DEBUG DRV_NAME ": ControlFrame: %d, PauseFrame: %d, "
852 		 "BackPressApp: %d, VLanTagFrame: %d\n",
853 		 TSV_GETBIT(tsv, TSV_TXCONTROLFRAME),
854 		 TSV_GETBIT(tsv, TSV_TXPAUSEFRAME),
855 		 TSV_GETBIT(tsv, TSV_BACKPRESSUREAPP),
856 		 TSV_GETBIT(tsv, TSV_TXVLANTAGFRAME));
857 }
858 
859 /*
860  * Receive Status vector
861  */
862 static void enc28j60_dump_rsv(struct enc28j60_net *priv, const char *msg,
863 			      u16 pk_ptr, int len, u16 sts)
864 {
865 	printk(KERN_DEBUG DRV_NAME ": %s - NextPk: 0x%04x - RSV:\n",
866 		msg, pk_ptr);
867 	printk(KERN_DEBUG DRV_NAME ": ByteCount: %d, DribbleNibble: %d\n", len,
868 		 RSV_GETBIT(sts, RSV_DRIBBLENIBBLE));
869 	printk(KERN_DEBUG DRV_NAME ": RxOK: %d, CRCErr:%d, LenChkErr: %d,"
870 		 " LenOutOfRange: %d\n", RSV_GETBIT(sts, RSV_RXOK),
871 		 RSV_GETBIT(sts, RSV_CRCERROR),
872 		 RSV_GETBIT(sts, RSV_LENCHECKERR),
873 		 RSV_GETBIT(sts, RSV_LENOUTOFRANGE));
874 	printk(KERN_DEBUG DRV_NAME ": Multicast: %d, Broadcast: %d, "
875 		 "LongDropEvent: %d, CarrierEvent: %d\n",
876 		 RSV_GETBIT(sts, RSV_RXMULTICAST),
877 		 RSV_GETBIT(sts, RSV_RXBROADCAST),
878 		 RSV_GETBIT(sts, RSV_RXLONGEVDROPEV),
879 		 RSV_GETBIT(sts, RSV_CARRIEREV));
880 	printk(KERN_DEBUG DRV_NAME ": ControlFrame: %d, PauseFrame: %d,"
881 		 " UnknownOp: %d, VLanTagFrame: %d\n",
882 		 RSV_GETBIT(sts, RSV_RXCONTROLFRAME),
883 		 RSV_GETBIT(sts, RSV_RXPAUSEFRAME),
884 		 RSV_GETBIT(sts, RSV_RXUNKNOWNOPCODE),
885 		 RSV_GETBIT(sts, RSV_RXTYPEVLAN));
886 }
887 
888 static void dump_packet(const char *msg, int len, const char *data)
889 {
890 	printk(KERN_DEBUG DRV_NAME ": %s - packet len:%d\n", msg, len);
891 	print_hex_dump(KERN_DEBUG, "pk data: ", DUMP_PREFIX_OFFSET, 16, 1,
892 			data, len, true);
893 }
894 
895 /*
896  * Hardware receive function.
897  * Read the buffer memory, update the FIFO pointer to free the buffer,
898  * check the status vector and decrement the packet counter.
899  */
900 static void enc28j60_hw_rx(struct net_device *ndev)
901 {
902 	struct enc28j60_net *priv = netdev_priv(ndev);
903 	struct sk_buff *skb = NULL;
904 	u16 erxrdpt, next_packet, rxstat;
905 	u8 rsv[RSV_SIZE];
906 	int len;
907 
908 	if (netif_msg_rx_status(priv))
909 		printk(KERN_DEBUG DRV_NAME ": RX pk_addr:0x%04x\n",
910 			priv->next_pk_ptr);
911 
912 	if (unlikely(priv->next_pk_ptr > RXEND_INIT)) {
913 		if (netif_msg_rx_err(priv))
914 			dev_err(&ndev->dev,
915 				"%s() Invalid packet address!! 0x%04x\n",
916 				__func__, priv->next_pk_ptr);
917 		/* packet address corrupted: reset RX logic */
918 		mutex_lock(&priv->lock);
919 		nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
920 		nolock_reg_bfset(priv, ECON1, ECON1_RXRST);
921 		nolock_reg_bfclr(priv, ECON1, ECON1_RXRST);
922 		nolock_rxfifo_init(priv, RXSTART_INIT, RXEND_INIT);
923 		nolock_reg_bfclr(priv, EIR, EIR_RXERIF);
924 		nolock_reg_bfset(priv, ECON1, ECON1_RXEN);
925 		mutex_unlock(&priv->lock);
926 		ndev->stats.rx_errors++;
927 		return;
928 	}
929 	/* Read next packet pointer and rx status vector */
930 	enc28j60_mem_read(priv, priv->next_pk_ptr, sizeof(rsv), rsv);
931 
932 	next_packet = rsv[1];
933 	next_packet <<= 8;
934 	next_packet |= rsv[0];
935 
936 	len = rsv[3];
937 	len <<= 8;
938 	len |= rsv[2];
939 
940 	rxstat = rsv[5];
941 	rxstat <<= 8;
942 	rxstat |= rsv[4];
943 
944 	if (netif_msg_rx_status(priv))
945 		enc28j60_dump_rsv(priv, __func__, next_packet, len, rxstat);
946 
947 	if (!RSV_GETBIT(rxstat, RSV_RXOK) || len > MAX_FRAMELEN) {
948 		if (netif_msg_rx_err(priv))
949 			dev_err(&ndev->dev, "Rx Error (%04x)\n", rxstat);
950 		ndev->stats.rx_errors++;
951 		if (RSV_GETBIT(rxstat, RSV_CRCERROR))
952 			ndev->stats.rx_crc_errors++;
953 		if (RSV_GETBIT(rxstat, RSV_LENCHECKERR))
954 			ndev->stats.rx_frame_errors++;
955 		if (len > MAX_FRAMELEN)
956 			ndev->stats.rx_over_errors++;
957 	} else {
958 		skb = netdev_alloc_skb(ndev, len + NET_IP_ALIGN);
959 		if (!skb) {
960 			if (netif_msg_rx_err(priv))
961 				dev_err(&ndev->dev,
962 					"out of memory for Rx'd frame\n");
963 			ndev->stats.rx_dropped++;
964 		} else {
965 			skb_reserve(skb, NET_IP_ALIGN);
966 			/* copy the packet from the receive buffer */
967 			enc28j60_mem_read(priv,
968 				rx_packet_start(priv->next_pk_ptr),
969 				len, skb_put(skb, len));
970 			if (netif_msg_pktdata(priv))
971 				dump_packet(__func__, skb->len, skb->data);
972 			skb->protocol = eth_type_trans(skb, ndev);
973 			/* update statistics */
974 			ndev->stats.rx_packets++;
975 			ndev->stats.rx_bytes += len;
976 			netif_rx_ni(skb);
977 		}
978 	}
979 	/*
980 	 * Move the RX read pointer to the start of the next
981 	 * received packet.
982 	 * This frees the memory we just read out
983 	 */
984 	erxrdpt = erxrdpt_workaround(next_packet, RXSTART_INIT, RXEND_INIT);
985 	if (netif_msg_hw(priv))
986 		printk(KERN_DEBUG DRV_NAME ": %s() ERXRDPT:0x%04x\n",
987 			__func__, erxrdpt);
988 
989 	mutex_lock(&priv->lock);
990 	nolock_regw_write(priv, ERXRDPTL, erxrdpt);
991 #ifdef CONFIG_ENC28J60_WRITEVERIFY
992 	if (netif_msg_drv(priv)) {
993 		u16 reg;
994 		reg = nolock_regw_read(priv, ERXRDPTL);
995 		if (reg != erxrdpt)
996 			printk(KERN_DEBUG DRV_NAME ": %s() ERXRDPT verify "
997 				"error (0x%04x - 0x%04x)\n", __func__,
998 				reg, erxrdpt);
999 	}
1000 #endif
1001 	priv->next_pk_ptr = next_packet;
1002 	/* we are done with this packet, decrement the packet counter */
1003 	nolock_reg_bfset(priv, ECON2, ECON2_PKTDEC);
1004 	mutex_unlock(&priv->lock);
1005 }
1006 
1007 /*
1008  * Calculate free space in RxFIFO
1009  */
1010 static int enc28j60_get_free_rxfifo(struct enc28j60_net *priv)
1011 {
1012 	int epkcnt, erxst, erxnd, erxwr, erxrd;
1013 	int free_space;
1014 
1015 	mutex_lock(&priv->lock);
1016 	epkcnt = nolock_regb_read(priv, EPKTCNT);
1017 	if (epkcnt >= 255)
1018 		free_space = -1;
1019 	else {
1020 		erxst = nolock_regw_read(priv, ERXSTL);
1021 		erxnd = nolock_regw_read(priv, ERXNDL);
1022 		erxwr = nolock_regw_read(priv, ERXWRPTL);
1023 		erxrd = nolock_regw_read(priv, ERXRDPTL);
1024 
1025 		if (erxwr > erxrd)
1026 			free_space = (erxnd - erxst) - (erxwr - erxrd);
1027 		else if (erxwr == erxrd)
1028 			free_space = (erxnd - erxst);
1029 		else
1030 			free_space = erxrd - erxwr - 1;
1031 	}
1032 	mutex_unlock(&priv->lock);
1033 	if (netif_msg_rx_status(priv))
1034 		printk(KERN_DEBUG DRV_NAME ": %s() free_space = %d\n",
1035 			__func__, free_space);
1036 	return free_space;
1037 }
1038 
1039 /*
1040  * Access the PHY to determine link status
1041  */
1042 static void enc28j60_check_link_status(struct net_device *ndev)
1043 {
1044 	struct enc28j60_net *priv = netdev_priv(ndev);
1045 	u16 reg;
1046 	int duplex;
1047 
1048 	reg = enc28j60_phy_read(priv, PHSTAT2);
1049 	if (netif_msg_hw(priv))
1050 		printk(KERN_DEBUG DRV_NAME ": %s() PHSTAT1: %04x, "
1051 			"PHSTAT2: %04x\n", __func__,
1052 			enc28j60_phy_read(priv, PHSTAT1), reg);
1053 	duplex = reg & PHSTAT2_DPXSTAT;
1054 
1055 	if (reg & PHSTAT2_LSTAT) {
1056 		netif_carrier_on(ndev);
1057 		if (netif_msg_ifup(priv))
1058 			dev_info(&ndev->dev, "link up - %s\n",
1059 				duplex ? "Full duplex" : "Half duplex");
1060 	} else {
1061 		if (netif_msg_ifdown(priv))
1062 			dev_info(&ndev->dev, "link down\n");
1063 		netif_carrier_off(ndev);
1064 	}
1065 }
1066 
1067 static void enc28j60_tx_clear(struct net_device *ndev, bool err)
1068 {
1069 	struct enc28j60_net *priv = netdev_priv(ndev);
1070 
1071 	if (err)
1072 		ndev->stats.tx_errors++;
1073 	else
1074 		ndev->stats.tx_packets++;
1075 
1076 	if (priv->tx_skb) {
1077 		if (!err)
1078 			ndev->stats.tx_bytes += priv->tx_skb->len;
1079 		dev_kfree_skb(priv->tx_skb);
1080 		priv->tx_skb = NULL;
1081 	}
1082 	locked_reg_bfclr(priv, ECON1, ECON1_TXRTS);
1083 	netif_wake_queue(ndev);
1084 }
1085 
1086 /*
1087  * RX handler
1088  * ignore PKTIF because is unreliable! (look at the errata datasheet)
1089  * check EPKTCNT is the suggested workaround.
1090  * We don't need to clear interrupt flag, automatically done when
1091  * enc28j60_hw_rx() decrements the packet counter.
1092  * Returns how many packet processed.
1093  */
1094 static int enc28j60_rx_interrupt(struct net_device *ndev)
1095 {
1096 	struct enc28j60_net *priv = netdev_priv(ndev);
1097 	int pk_counter, ret;
1098 
1099 	pk_counter = locked_regb_read(priv, EPKTCNT);
1100 	if (pk_counter && netif_msg_intr(priv))
1101 		printk(KERN_DEBUG DRV_NAME ": intRX, pk_cnt: %d\n", pk_counter);
1102 	if (pk_counter > priv->max_pk_counter) {
1103 		/* update statistics */
1104 		priv->max_pk_counter = pk_counter;
1105 		if (netif_msg_rx_status(priv) && priv->max_pk_counter > 1)
1106 			printk(KERN_DEBUG DRV_NAME ": RX max_pk_cnt: %d\n",
1107 				priv->max_pk_counter);
1108 	}
1109 	ret = pk_counter;
1110 	while (pk_counter-- > 0)
1111 		enc28j60_hw_rx(ndev);
1112 
1113 	return ret;
1114 }
1115 
1116 static void enc28j60_irq_work_handler(struct work_struct *work)
1117 {
1118 	struct enc28j60_net *priv =
1119 		container_of(work, struct enc28j60_net, irq_work);
1120 	struct net_device *ndev = priv->netdev;
1121 	int intflags, loop;
1122 
1123 	if (netif_msg_intr(priv))
1124 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1125 	/* disable further interrupts */
1126 	locked_reg_bfclr(priv, EIE, EIE_INTIE);
1127 
1128 	do {
1129 		loop = 0;
1130 		intflags = locked_regb_read(priv, EIR);
1131 		/* DMA interrupt handler (not currently used) */
1132 		if ((intflags & EIR_DMAIF) != 0) {
1133 			loop++;
1134 			if (netif_msg_intr(priv))
1135 				printk(KERN_DEBUG DRV_NAME
1136 					": intDMA(%d)\n", loop);
1137 			locked_reg_bfclr(priv, EIR, EIR_DMAIF);
1138 		}
1139 		/* LINK changed handler */
1140 		if ((intflags & EIR_LINKIF) != 0) {
1141 			loop++;
1142 			if (netif_msg_intr(priv))
1143 				printk(KERN_DEBUG DRV_NAME
1144 					": intLINK(%d)\n", loop);
1145 			enc28j60_check_link_status(ndev);
1146 			/* read PHIR to clear the flag */
1147 			enc28j60_phy_read(priv, PHIR);
1148 		}
1149 		/* TX complete handler */
1150 		if ((intflags & EIR_TXIF) != 0) {
1151 			bool err = false;
1152 			loop++;
1153 			if (netif_msg_intr(priv))
1154 				printk(KERN_DEBUG DRV_NAME
1155 					": intTX(%d)\n", loop);
1156 			priv->tx_retry_count = 0;
1157 			if (locked_regb_read(priv, ESTAT) & ESTAT_TXABRT) {
1158 				if (netif_msg_tx_err(priv))
1159 					dev_err(&ndev->dev,
1160 						"Tx Error (aborted)\n");
1161 				err = true;
1162 			}
1163 			if (netif_msg_tx_done(priv)) {
1164 				u8 tsv[TSV_SIZE];
1165 				enc28j60_read_tsv(priv, tsv);
1166 				enc28j60_dump_tsv(priv, "Tx Done", tsv);
1167 			}
1168 			enc28j60_tx_clear(ndev, err);
1169 			locked_reg_bfclr(priv, EIR, EIR_TXIF);
1170 		}
1171 		/* TX Error handler */
1172 		if ((intflags & EIR_TXERIF) != 0) {
1173 			u8 tsv[TSV_SIZE];
1174 
1175 			loop++;
1176 			if (netif_msg_intr(priv))
1177 				printk(KERN_DEBUG DRV_NAME
1178 					": intTXErr(%d)\n", loop);
1179 			locked_reg_bfclr(priv, ECON1, ECON1_TXRTS);
1180 			enc28j60_read_tsv(priv, tsv);
1181 			if (netif_msg_tx_err(priv))
1182 				enc28j60_dump_tsv(priv, "Tx Error", tsv);
1183 			/* Reset TX logic */
1184 			mutex_lock(&priv->lock);
1185 			nolock_reg_bfset(priv, ECON1, ECON1_TXRST);
1186 			nolock_reg_bfclr(priv, ECON1, ECON1_TXRST);
1187 			nolock_txfifo_init(priv, TXSTART_INIT, TXEND_INIT);
1188 			mutex_unlock(&priv->lock);
1189 			/* Transmit Late collision check for retransmit */
1190 			if (TSV_GETBIT(tsv, TSV_TXLATECOLLISION)) {
1191 				if (netif_msg_tx_err(priv))
1192 					printk(KERN_DEBUG DRV_NAME
1193 						": LateCollision TXErr (%d)\n",
1194 						priv->tx_retry_count);
1195 				if (priv->tx_retry_count++ < MAX_TX_RETRYCOUNT)
1196 					locked_reg_bfset(priv, ECON1,
1197 							   ECON1_TXRTS);
1198 				else
1199 					enc28j60_tx_clear(ndev, true);
1200 			} else
1201 				enc28j60_tx_clear(ndev, true);
1202 			locked_reg_bfclr(priv, EIR, EIR_TXERIF);
1203 		}
1204 		/* RX Error handler */
1205 		if ((intflags & EIR_RXERIF) != 0) {
1206 			loop++;
1207 			if (netif_msg_intr(priv))
1208 				printk(KERN_DEBUG DRV_NAME
1209 					": intRXErr(%d)\n", loop);
1210 			/* Check free FIFO space to flag RX overrun */
1211 			if (enc28j60_get_free_rxfifo(priv) <= 0) {
1212 				if (netif_msg_rx_err(priv))
1213 					printk(KERN_DEBUG DRV_NAME
1214 						": RX Overrun\n");
1215 				ndev->stats.rx_dropped++;
1216 			}
1217 			locked_reg_bfclr(priv, EIR, EIR_RXERIF);
1218 		}
1219 		/* RX handler */
1220 		if (enc28j60_rx_interrupt(ndev))
1221 			loop++;
1222 	} while (loop);
1223 
1224 	/* re-enable interrupts */
1225 	locked_reg_bfset(priv, EIE, EIE_INTIE);
1226 	if (netif_msg_intr(priv))
1227 		printk(KERN_DEBUG DRV_NAME ": %s() exit\n", __func__);
1228 }
1229 
1230 /*
1231  * Hardware transmit function.
1232  * Fill the buffer memory and send the contents of the transmit buffer
1233  * onto the network
1234  */
1235 static void enc28j60_hw_tx(struct enc28j60_net *priv)
1236 {
1237 	if (netif_msg_tx_queued(priv))
1238 		printk(KERN_DEBUG DRV_NAME
1239 			": Tx Packet Len:%d\n", priv->tx_skb->len);
1240 
1241 	if (netif_msg_pktdata(priv))
1242 		dump_packet(__func__,
1243 			    priv->tx_skb->len, priv->tx_skb->data);
1244 	enc28j60_packet_write(priv, priv->tx_skb->len, priv->tx_skb->data);
1245 
1246 #ifdef CONFIG_ENC28J60_WRITEVERIFY
1247 	/* readback and verify written data */
1248 	if (netif_msg_drv(priv)) {
1249 		int test_len, k;
1250 		u8 test_buf[64]; /* limit the test to the first 64 bytes */
1251 		int okflag;
1252 
1253 		test_len = priv->tx_skb->len;
1254 		if (test_len > sizeof(test_buf))
1255 			test_len = sizeof(test_buf);
1256 
1257 		/* + 1 to skip control byte */
1258 		enc28j60_mem_read(priv, TXSTART_INIT + 1, test_len, test_buf);
1259 		okflag = 1;
1260 		for (k = 0; k < test_len; k++) {
1261 			if (priv->tx_skb->data[k] != test_buf[k]) {
1262 				printk(KERN_DEBUG DRV_NAME
1263 					 ": Error, %d location differ: "
1264 					 "0x%02x-0x%02x\n", k,
1265 					 priv->tx_skb->data[k], test_buf[k]);
1266 				okflag = 0;
1267 			}
1268 		}
1269 		if (!okflag)
1270 			printk(KERN_DEBUG DRV_NAME ": Tx write buffer, "
1271 				"verify ERROR!\n");
1272 	}
1273 #endif
1274 	/* set TX request flag */
1275 	locked_reg_bfset(priv, ECON1, ECON1_TXRTS);
1276 }
1277 
1278 static netdev_tx_t enc28j60_send_packet(struct sk_buff *skb,
1279 					struct net_device *dev)
1280 {
1281 	struct enc28j60_net *priv = netdev_priv(dev);
1282 
1283 	if (netif_msg_tx_queued(priv))
1284 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1285 
1286 	/* If some error occurs while trying to transmit this
1287 	 * packet, you should return '1' from this function.
1288 	 * In such a case you _may not_ do anything to the
1289 	 * SKB, it is still owned by the network queueing
1290 	 * layer when an error is returned.  This means you
1291 	 * may not modify any SKB fields, you may not free
1292 	 * the SKB, etc.
1293 	 */
1294 	netif_stop_queue(dev);
1295 
1296 	/* Remember the skb for deferred processing */
1297 	priv->tx_skb = skb;
1298 	schedule_work(&priv->tx_work);
1299 
1300 	return NETDEV_TX_OK;
1301 }
1302 
1303 static void enc28j60_tx_work_handler(struct work_struct *work)
1304 {
1305 	struct enc28j60_net *priv =
1306 		container_of(work, struct enc28j60_net, tx_work);
1307 
1308 	/* actual delivery of data */
1309 	enc28j60_hw_tx(priv);
1310 }
1311 
1312 static irqreturn_t enc28j60_irq(int irq, void *dev_id)
1313 {
1314 	struct enc28j60_net *priv = dev_id;
1315 
1316 	/*
1317 	 * Can't do anything in interrupt context because we need to
1318 	 * block (spi_sync() is blocking) so fire of the interrupt
1319 	 * handling workqueue.
1320 	 * Remember that we access enc28j60 registers through SPI bus
1321 	 * via spi_sync() call.
1322 	 */
1323 	schedule_work(&priv->irq_work);
1324 
1325 	return IRQ_HANDLED;
1326 }
1327 
1328 static void enc28j60_tx_timeout(struct net_device *ndev)
1329 {
1330 	struct enc28j60_net *priv = netdev_priv(ndev);
1331 
1332 	if (netif_msg_timer(priv))
1333 		dev_err(&ndev->dev, DRV_NAME " tx timeout\n");
1334 
1335 	ndev->stats.tx_errors++;
1336 	/* can't restart safely under softirq */
1337 	schedule_work(&priv->restart_work);
1338 }
1339 
1340 /*
1341  * Open/initialize the board. This is called (in the current kernel)
1342  * sometime after booting when the 'ifconfig' program is run.
1343  *
1344  * This routine should set everything up anew at each open, even
1345  * registers that "should" only need to be set once at boot, so that
1346  * there is non-reboot way to recover if something goes wrong.
1347  */
1348 static int enc28j60_net_open(struct net_device *dev)
1349 {
1350 	struct enc28j60_net *priv = netdev_priv(dev);
1351 
1352 	if (netif_msg_drv(priv))
1353 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1354 
1355 	if (!is_valid_ether_addr(dev->dev_addr)) {
1356 		if (netif_msg_ifup(priv))
1357 			dev_err(&dev->dev, "invalid MAC address %pM\n",
1358 				dev->dev_addr);
1359 		return -EADDRNOTAVAIL;
1360 	}
1361 	/* Reset the hardware here (and take it out of low power mode) */
1362 	enc28j60_lowpower(priv, false);
1363 	enc28j60_hw_disable(priv);
1364 	if (!enc28j60_hw_init(priv)) {
1365 		if (netif_msg_ifup(priv))
1366 			dev_err(&dev->dev, "hw_reset() failed\n");
1367 		return -EINVAL;
1368 	}
1369 	/* Update the MAC address (in case user has changed it) */
1370 	enc28j60_set_hw_macaddr(dev);
1371 	/* Enable interrupts */
1372 	enc28j60_hw_enable(priv);
1373 	/* check link status */
1374 	enc28j60_check_link_status(dev);
1375 	/* We are now ready to accept transmit requests from
1376 	 * the queueing layer of the networking.
1377 	 */
1378 	netif_start_queue(dev);
1379 
1380 	return 0;
1381 }
1382 
1383 /* The inverse routine to net_open(). */
1384 static int enc28j60_net_close(struct net_device *dev)
1385 {
1386 	struct enc28j60_net *priv = netdev_priv(dev);
1387 
1388 	if (netif_msg_drv(priv))
1389 		printk(KERN_DEBUG DRV_NAME ": %s() enter\n", __func__);
1390 
1391 	enc28j60_hw_disable(priv);
1392 	enc28j60_lowpower(priv, true);
1393 	netif_stop_queue(dev);
1394 
1395 	return 0;
1396 }
1397 
1398 /*
1399  * Set or clear the multicast filter for this adapter
1400  * num_addrs == -1	Promiscuous mode, receive all packets
1401  * num_addrs == 0	Normal mode, filter out multicast packets
1402  * num_addrs > 0	Multicast mode, receive normal and MC packets
1403  */
1404 static void enc28j60_set_multicast_list(struct net_device *dev)
1405 {
1406 	struct enc28j60_net *priv = netdev_priv(dev);
1407 	int oldfilter = priv->rxfilter;
1408 
1409 	if (dev->flags & IFF_PROMISC) {
1410 		if (netif_msg_link(priv))
1411 			dev_info(&dev->dev, "promiscuous mode\n");
1412 		priv->rxfilter = RXFILTER_PROMISC;
1413 	} else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev)) {
1414 		if (netif_msg_link(priv))
1415 			dev_info(&dev->dev, "%smulticast mode\n",
1416 				(dev->flags & IFF_ALLMULTI) ? "all-" : "");
1417 		priv->rxfilter = RXFILTER_MULTI;
1418 	} else {
1419 		if (netif_msg_link(priv))
1420 			dev_info(&dev->dev, "normal mode\n");
1421 		priv->rxfilter = RXFILTER_NORMAL;
1422 	}
1423 
1424 	if (oldfilter != priv->rxfilter)
1425 		schedule_work(&priv->setrx_work);
1426 }
1427 
1428 static void enc28j60_setrx_work_handler(struct work_struct *work)
1429 {
1430 	struct enc28j60_net *priv =
1431 		container_of(work, struct enc28j60_net, setrx_work);
1432 
1433 	if (priv->rxfilter == RXFILTER_PROMISC) {
1434 		if (netif_msg_drv(priv))
1435 			printk(KERN_DEBUG DRV_NAME ": promiscuous mode\n");
1436 		locked_regb_write(priv, ERXFCON, 0x00);
1437 	} else if (priv->rxfilter == RXFILTER_MULTI) {
1438 		if (netif_msg_drv(priv))
1439 			printk(KERN_DEBUG DRV_NAME ": multicast mode\n");
1440 		locked_regb_write(priv, ERXFCON,
1441 					ERXFCON_UCEN | ERXFCON_CRCEN |
1442 					ERXFCON_BCEN | ERXFCON_MCEN);
1443 	} else {
1444 		if (netif_msg_drv(priv))
1445 			printk(KERN_DEBUG DRV_NAME ": normal mode\n");
1446 		locked_regb_write(priv, ERXFCON,
1447 					ERXFCON_UCEN | ERXFCON_CRCEN |
1448 					ERXFCON_BCEN);
1449 	}
1450 }
1451 
1452 static void enc28j60_restart_work_handler(struct work_struct *work)
1453 {
1454 	struct enc28j60_net *priv =
1455 			container_of(work, struct enc28j60_net, restart_work);
1456 	struct net_device *ndev = priv->netdev;
1457 	int ret;
1458 
1459 	rtnl_lock();
1460 	if (netif_running(ndev)) {
1461 		enc28j60_net_close(ndev);
1462 		ret = enc28j60_net_open(ndev);
1463 		if (unlikely(ret)) {
1464 			dev_info(&ndev->dev, " could not restart %d\n", ret);
1465 			dev_close(ndev);
1466 		}
1467 	}
1468 	rtnl_unlock();
1469 }
1470 
1471 /* ......................... ETHTOOL SUPPORT ........................... */
1472 
1473 static void
1474 enc28j60_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1475 {
1476 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1477 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1478 	strlcpy(info->bus_info,
1479 		dev_name(dev->dev.parent), sizeof(info->bus_info));
1480 }
1481 
1482 static int
1483 enc28j60_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1484 {
1485 	struct enc28j60_net *priv = netdev_priv(dev);
1486 
1487 	cmd->transceiver = XCVR_INTERNAL;
1488 	cmd->supported	= SUPPORTED_10baseT_Half
1489 			| SUPPORTED_10baseT_Full
1490 			| SUPPORTED_TP;
1491 	ethtool_cmd_speed_set(cmd,  SPEED_10);
1492 	cmd->duplex	= priv->full_duplex ? DUPLEX_FULL : DUPLEX_HALF;
1493 	cmd->port	= PORT_TP;
1494 	cmd->autoneg	= AUTONEG_DISABLE;
1495 
1496 	return 0;
1497 }
1498 
1499 static int
1500 enc28j60_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1501 {
1502 	return enc28j60_setlink(dev, cmd->autoneg,
1503 				ethtool_cmd_speed(cmd), cmd->duplex);
1504 }
1505 
1506 static u32 enc28j60_get_msglevel(struct net_device *dev)
1507 {
1508 	struct enc28j60_net *priv = netdev_priv(dev);
1509 	return priv->msg_enable;
1510 }
1511 
1512 static void enc28j60_set_msglevel(struct net_device *dev, u32 val)
1513 {
1514 	struct enc28j60_net *priv = netdev_priv(dev);
1515 	priv->msg_enable = val;
1516 }
1517 
1518 static const struct ethtool_ops enc28j60_ethtool_ops = {
1519 	.get_settings	= enc28j60_get_settings,
1520 	.set_settings	= enc28j60_set_settings,
1521 	.get_drvinfo	= enc28j60_get_drvinfo,
1522 	.get_msglevel	= enc28j60_get_msglevel,
1523 	.set_msglevel	= enc28j60_set_msglevel,
1524 };
1525 
1526 static int enc28j60_chipset_init(struct net_device *dev)
1527 {
1528 	struct enc28j60_net *priv = netdev_priv(dev);
1529 
1530 	return enc28j60_hw_init(priv);
1531 }
1532 
1533 static const struct net_device_ops enc28j60_netdev_ops = {
1534 	.ndo_open		= enc28j60_net_open,
1535 	.ndo_stop		= enc28j60_net_close,
1536 	.ndo_start_xmit		= enc28j60_send_packet,
1537 	.ndo_set_rx_mode	= enc28j60_set_multicast_list,
1538 	.ndo_set_mac_address	= enc28j60_set_mac_address,
1539 	.ndo_tx_timeout		= enc28j60_tx_timeout,
1540 	.ndo_change_mtu		= eth_change_mtu,
1541 	.ndo_validate_addr	= eth_validate_addr,
1542 };
1543 
1544 static int __devinit enc28j60_probe(struct spi_device *spi)
1545 {
1546 	struct net_device *dev;
1547 	struct enc28j60_net *priv;
1548 	int ret = 0;
1549 
1550 	if (netif_msg_drv(&debug))
1551 		dev_info(&spi->dev, DRV_NAME " Ethernet driver %s loaded\n",
1552 			DRV_VERSION);
1553 
1554 	dev = alloc_etherdev(sizeof(struct enc28j60_net));
1555 	if (!dev) {
1556 		ret = -ENOMEM;
1557 		goto error_alloc;
1558 	}
1559 	priv = netdev_priv(dev);
1560 
1561 	priv->netdev = dev;	/* priv to netdev reference */
1562 	priv->spi = spi;	/* priv to spi reference */
1563 	priv->msg_enable = netif_msg_init(debug.msg_enable,
1564 						ENC28J60_MSG_DEFAULT);
1565 	mutex_init(&priv->lock);
1566 	INIT_WORK(&priv->tx_work, enc28j60_tx_work_handler);
1567 	INIT_WORK(&priv->setrx_work, enc28j60_setrx_work_handler);
1568 	INIT_WORK(&priv->irq_work, enc28j60_irq_work_handler);
1569 	INIT_WORK(&priv->restart_work, enc28j60_restart_work_handler);
1570 	dev_set_drvdata(&spi->dev, priv);	/* spi to priv reference */
1571 	SET_NETDEV_DEV(dev, &spi->dev);
1572 
1573 	if (!enc28j60_chipset_init(dev)) {
1574 		if (netif_msg_probe(priv))
1575 			dev_info(&spi->dev, DRV_NAME " chip not found\n");
1576 		ret = -EIO;
1577 		goto error_irq;
1578 	}
1579 	eth_hw_addr_random(dev);
1580 	enc28j60_set_hw_macaddr(dev);
1581 
1582 	/* Board setup must set the relevant edge trigger type;
1583 	 * level triggers won't currently work.
1584 	 */
1585 	ret = request_irq(spi->irq, enc28j60_irq, 0, DRV_NAME, priv);
1586 	if (ret < 0) {
1587 		if (netif_msg_probe(priv))
1588 			dev_err(&spi->dev, DRV_NAME ": request irq %d failed "
1589 				"(ret = %d)\n", spi->irq, ret);
1590 		goto error_irq;
1591 	}
1592 
1593 	dev->if_port = IF_PORT_10BASET;
1594 	dev->irq = spi->irq;
1595 	dev->netdev_ops = &enc28j60_netdev_ops;
1596 	dev->watchdog_timeo = TX_TIMEOUT;
1597 	SET_ETHTOOL_OPS(dev, &enc28j60_ethtool_ops);
1598 
1599 	enc28j60_lowpower(priv, true);
1600 
1601 	ret = register_netdev(dev);
1602 	if (ret) {
1603 		if (netif_msg_probe(priv))
1604 			dev_err(&spi->dev, "register netdev " DRV_NAME
1605 				" failed (ret = %d)\n", ret);
1606 		goto error_register;
1607 	}
1608 	dev_info(&dev->dev, DRV_NAME " driver registered\n");
1609 
1610 	return 0;
1611 
1612 error_register:
1613 	free_irq(spi->irq, priv);
1614 error_irq:
1615 	free_netdev(dev);
1616 error_alloc:
1617 	return ret;
1618 }
1619 
1620 static int __devexit enc28j60_remove(struct spi_device *spi)
1621 {
1622 	struct enc28j60_net *priv = dev_get_drvdata(&spi->dev);
1623 
1624 	if (netif_msg_drv(priv))
1625 		printk(KERN_DEBUG DRV_NAME ": remove\n");
1626 
1627 	unregister_netdev(priv->netdev);
1628 	free_irq(spi->irq, priv);
1629 	free_netdev(priv->netdev);
1630 
1631 	return 0;
1632 }
1633 
1634 static struct spi_driver enc28j60_driver = {
1635 	.driver = {
1636 		   .name = DRV_NAME,
1637 		   .owner = THIS_MODULE,
1638 	 },
1639 	.probe = enc28j60_probe,
1640 	.remove = __devexit_p(enc28j60_remove),
1641 };
1642 
1643 static int __init enc28j60_init(void)
1644 {
1645 	msec20_to_jiffies = msecs_to_jiffies(20);
1646 
1647 	return spi_register_driver(&enc28j60_driver);
1648 }
1649 
1650 module_init(enc28j60_init);
1651 
1652 static void __exit enc28j60_exit(void)
1653 {
1654 	spi_unregister_driver(&enc28j60_driver);
1655 }
1656 
1657 module_exit(enc28j60_exit);
1658 
1659 MODULE_DESCRIPTION(DRV_NAME " ethernet driver");
1660 MODULE_AUTHOR("Claudio Lanconelli <lanconelli.claudio@eptar.com>");
1661 MODULE_LICENSE("GPL");
1662 module_param_named(debug, debug.msg_enable, int, 0);
1663 MODULE_PARM_DESC(debug, "Debug verbosity level (0=none, ..., ffff=all)");
1664 MODULE_ALIAS("spi:" DRV_NAME);
1665