1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /**
3  * Microchip ENCX24J600 ethernet driver
4  *
5  * Copyright (C) 2015 Gridpoint
6  * Author: Jon Ringle <jringle@gridpoint.com>
7  */
8 
9 #include <linux/device.h>
10 #include <linux/errno.h>
11 #include <linux/etherdevice.h>
12 #include <linux/ethtool.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/netdevice.h>
17 #include <linux/regmap.h>
18 #include <linux/skbuff.h>
19 #include <linux/spi/spi.h>
20 
21 #include "encx24j600_hw.h"
22 
23 #define DRV_NAME	"encx24j600"
24 #define DRV_VERSION	"1.0"
25 
26 #define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK)
27 static int debug = -1;
28 module_param(debug, int, 0000);
29 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
30 
31 /* SRAM memory layout:
32  *
33  * 0x0000-0x05ff TX buffers  1.5KB  (1*1536) reside in the GP area in SRAM
34  * 0x0600-0x5fff RX buffers 22.5KB (15*1536) reside in the RX area in SRAM
35  */
36 #define ENC_TX_BUF_START 0x0000U
37 #define ENC_RX_BUF_START 0x0600U
38 #define ENC_RX_BUF_END   0x5fffU
39 #define ENC_SRAM_SIZE    0x6000U
40 
41 enum {
42 	RXFILTER_NORMAL,
43 	RXFILTER_MULTI,
44 	RXFILTER_PROMISC
45 };
46 
47 struct encx24j600_priv {
48 	struct net_device        *ndev;
49 	struct mutex              lock; /* device access lock */
50 	struct encx24j600_context ctx;
51 	struct sk_buff           *tx_skb;
52 	struct task_struct       *kworker_task;
53 	struct kthread_worker     kworker;
54 	struct kthread_work       tx_work;
55 	struct kthread_work       setrx_work;
56 	u16                       next_packet;
57 	bool                      hw_enabled;
58 	bool                      full_duplex;
59 	bool                      autoneg;
60 	u16                       speed;
61 	int                       rxfilter;
62 	u32                       msg_enable;
63 };
64 
65 static void dump_packet(const char *msg, int len, const char *data)
66 {
67 	pr_debug(DRV_NAME ": %s - packet len:%d\n", msg, len);
68 	print_hex_dump_bytes("pk data: ", DUMP_PREFIX_OFFSET, data, len);
69 }
70 
71 static void encx24j600_dump_rsv(struct encx24j600_priv *priv, const char *msg,
72 				struct rsv *rsv)
73 {
74 	struct net_device *dev = priv->ndev;
75 
76 	netdev_info(dev, "RX packet Len:%d\n", rsv->len);
77 	netdev_dbg(dev, "%s - NextPk: 0x%04x\n", msg,
78 		   rsv->next_packet);
79 	netdev_dbg(dev, "RxOK: %d, DribbleNibble: %d\n",
80 		   RSV_GETBIT(rsv->rxstat, RSV_RXOK),
81 		   RSV_GETBIT(rsv->rxstat, RSV_DRIBBLENIBBLE));
82 	netdev_dbg(dev, "CRCErr:%d, LenChkErr: %d, LenOutOfRange: %d\n",
83 		   RSV_GETBIT(rsv->rxstat, RSV_CRCERROR),
84 		   RSV_GETBIT(rsv->rxstat, RSV_LENCHECKERR),
85 		   RSV_GETBIT(rsv->rxstat, RSV_LENOUTOFRANGE));
86 	netdev_dbg(dev, "Multicast: %d, Broadcast: %d, LongDropEvent: %d, CarrierEvent: %d\n",
87 		   RSV_GETBIT(rsv->rxstat, RSV_RXMULTICAST),
88 		   RSV_GETBIT(rsv->rxstat, RSV_RXBROADCAST),
89 		   RSV_GETBIT(rsv->rxstat, RSV_RXLONGEVDROPEV),
90 		   RSV_GETBIT(rsv->rxstat, RSV_CARRIEREV));
91 	netdev_dbg(dev, "ControlFrame: %d, PauseFrame: %d, UnknownOp: %d, VLanTagFrame: %d\n",
92 		   RSV_GETBIT(rsv->rxstat, RSV_RXCONTROLFRAME),
93 		   RSV_GETBIT(rsv->rxstat, RSV_RXPAUSEFRAME),
94 		   RSV_GETBIT(rsv->rxstat, RSV_RXUNKNOWNOPCODE),
95 		   RSV_GETBIT(rsv->rxstat, RSV_RXTYPEVLAN));
96 }
97 
98 static u16 encx24j600_read_reg(struct encx24j600_priv *priv, u8 reg)
99 {
100 	struct net_device *dev = priv->ndev;
101 	unsigned int val = 0;
102 	int ret = regmap_read(priv->ctx.regmap, reg, &val);
103 
104 	if (unlikely(ret))
105 		netif_err(priv, drv, dev, "%s: error %d reading reg %02x\n",
106 			  __func__, ret, reg);
107 	return val;
108 }
109 
110 static void encx24j600_write_reg(struct encx24j600_priv *priv, u8 reg, u16 val)
111 {
112 	struct net_device *dev = priv->ndev;
113 	int ret = regmap_write(priv->ctx.regmap, reg, val);
114 
115 	if (unlikely(ret))
116 		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
117 			  __func__, ret, reg, val);
118 }
119 
120 static void encx24j600_update_reg(struct encx24j600_priv *priv, u8 reg,
121 				  u16 mask, u16 val)
122 {
123 	struct net_device *dev = priv->ndev;
124 	int ret = regmap_update_bits(priv->ctx.regmap, reg, mask, val);
125 
126 	if (unlikely(ret))
127 		netif_err(priv, drv, dev, "%s: error %d updating reg %02x=%04x~%04x\n",
128 			  __func__, ret, reg, val, mask);
129 }
130 
131 static u16 encx24j600_read_phy(struct encx24j600_priv *priv, u8 reg)
132 {
133 	struct net_device *dev = priv->ndev;
134 	unsigned int val = 0;
135 	int ret = regmap_read(priv->ctx.phymap, reg, &val);
136 
137 	if (unlikely(ret))
138 		netif_err(priv, drv, dev, "%s: error %d reading %02x\n",
139 			  __func__, ret, reg);
140 	return val;
141 }
142 
143 static void encx24j600_write_phy(struct encx24j600_priv *priv, u8 reg, u16 val)
144 {
145 	struct net_device *dev = priv->ndev;
146 	int ret = regmap_write(priv->ctx.phymap, reg, val);
147 
148 	if (unlikely(ret))
149 		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
150 			  __func__, ret, reg, val);
151 }
152 
153 static void encx24j600_clr_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
154 {
155 	encx24j600_update_reg(priv, reg, mask, 0);
156 }
157 
158 static void encx24j600_set_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
159 {
160 	encx24j600_update_reg(priv, reg, mask, mask);
161 }
162 
163 static void encx24j600_cmd(struct encx24j600_priv *priv, u8 cmd)
164 {
165 	struct net_device *dev = priv->ndev;
166 	int ret = regmap_write(priv->ctx.regmap, cmd, 0);
167 
168 	if (unlikely(ret))
169 		netif_err(priv, drv, dev, "%s: error %d with cmd %02x\n",
170 			  __func__, ret, cmd);
171 }
172 
173 static int encx24j600_raw_read(struct encx24j600_priv *priv, u8 reg, u8 *data,
174 			       size_t count)
175 {
176 	int ret;
177 
178 	mutex_lock(&priv->ctx.mutex);
179 	ret = regmap_encx24j600_spi_read(&priv->ctx, reg, data, count);
180 	mutex_unlock(&priv->ctx.mutex);
181 
182 	return ret;
183 }
184 
185 static int encx24j600_raw_write(struct encx24j600_priv *priv, u8 reg,
186 				const u8 *data, size_t count)
187 {
188 	int ret;
189 
190 	mutex_lock(&priv->ctx.mutex);
191 	ret = regmap_encx24j600_spi_write(&priv->ctx, reg, data, count);
192 	mutex_unlock(&priv->ctx.mutex);
193 
194 	return ret;
195 }
196 
197 static void encx24j600_update_phcon1(struct encx24j600_priv *priv)
198 {
199 	u16 phcon1 = encx24j600_read_phy(priv, PHCON1);
200 
201 	if (priv->autoneg == AUTONEG_ENABLE) {
202 		phcon1 |= ANEN | RENEG;
203 	} else {
204 		phcon1 &= ~ANEN;
205 		if (priv->speed == SPEED_100)
206 			phcon1 |= SPD100;
207 		else
208 			phcon1 &= ~SPD100;
209 
210 		if (priv->full_duplex)
211 			phcon1 |= PFULDPX;
212 		else
213 			phcon1 &= ~PFULDPX;
214 	}
215 	encx24j600_write_phy(priv, PHCON1, phcon1);
216 }
217 
218 /* Waits for autonegotiation to complete. */
219 static int encx24j600_wait_for_autoneg(struct encx24j600_priv *priv)
220 {
221 	struct net_device *dev = priv->ndev;
222 	unsigned long timeout = jiffies + msecs_to_jiffies(2000);
223 	u16 phstat1;
224 	u16 estat;
225 	int ret = 0;
226 
227 	phstat1 = encx24j600_read_phy(priv, PHSTAT1);
228 	while ((phstat1 & ANDONE) == 0) {
229 		if (time_after(jiffies, timeout)) {
230 			u16 phstat3;
231 
232 			netif_notice(priv, drv, dev, "timeout waiting for autoneg done\n");
233 
234 			priv->autoneg = AUTONEG_DISABLE;
235 			phstat3 = encx24j600_read_phy(priv, PHSTAT3);
236 			priv->speed = (phstat3 & PHY3SPD100)
237 				      ? SPEED_100 : SPEED_10;
238 			priv->full_duplex = (phstat3 & PHY3DPX) ? 1 : 0;
239 			encx24j600_update_phcon1(priv);
240 			netif_notice(priv, drv, dev, "Using parallel detection: %s/%s",
241 				     priv->speed == SPEED_100 ? "100" : "10",
242 				     priv->full_duplex ? "Full" : "Half");
243 
244 			return -ETIMEDOUT;
245 		}
246 		cpu_relax();
247 		phstat1 = encx24j600_read_phy(priv, PHSTAT1);
248 	}
249 
250 	estat = encx24j600_read_reg(priv, ESTAT);
251 	if (estat & PHYDPX) {
252 		encx24j600_set_bits(priv, MACON2, FULDPX);
253 		encx24j600_write_reg(priv, MABBIPG, 0x15);
254 	} else {
255 		encx24j600_clr_bits(priv, MACON2, FULDPX);
256 		encx24j600_write_reg(priv, MABBIPG, 0x12);
257 		/* Max retransmittions attempt  */
258 		encx24j600_write_reg(priv, MACLCON, 0x370f);
259 	}
260 
261 	return ret;
262 }
263 
264 /* Access the PHY to determine link status */
265 static void encx24j600_check_link_status(struct encx24j600_priv *priv)
266 {
267 	struct net_device *dev = priv->ndev;
268 	u16 estat;
269 
270 	estat = encx24j600_read_reg(priv, ESTAT);
271 
272 	if (estat & PHYLNK) {
273 		if (priv->autoneg == AUTONEG_ENABLE)
274 			encx24j600_wait_for_autoneg(priv);
275 
276 		netif_carrier_on(dev);
277 		netif_info(priv, ifup, dev, "link up\n");
278 	} else {
279 		netif_info(priv, ifdown, dev, "link down\n");
280 
281 		/* Re-enable autoneg since we won't know what we might be
282 		 * connected to when the link is brought back up again.
283 		 */
284 		priv->autoneg  = AUTONEG_ENABLE;
285 		priv->full_duplex = true;
286 		priv->speed = SPEED_100;
287 		netif_carrier_off(dev);
288 	}
289 }
290 
291 static void encx24j600_int_link_handler(struct encx24j600_priv *priv)
292 {
293 	struct net_device *dev = priv->ndev;
294 
295 	netif_dbg(priv, intr, dev, "%s", __func__);
296 	encx24j600_check_link_status(priv);
297 	encx24j600_clr_bits(priv, EIR, LINKIF);
298 }
299 
300 static void encx24j600_tx_complete(struct encx24j600_priv *priv, bool err)
301 {
302 	struct net_device *dev = priv->ndev;
303 
304 	if (!priv->tx_skb) {
305 		BUG();
306 		return;
307 	}
308 
309 	mutex_lock(&priv->lock);
310 
311 	if (err)
312 		dev->stats.tx_errors++;
313 	else
314 		dev->stats.tx_packets++;
315 
316 	dev->stats.tx_bytes += priv->tx_skb->len;
317 
318 	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
319 
320 	netif_dbg(priv, tx_done, dev, "TX Done%s\n", err ? ": Err" : "");
321 
322 	dev_kfree_skb(priv->tx_skb);
323 	priv->tx_skb = NULL;
324 
325 	netif_wake_queue(dev);
326 
327 	mutex_unlock(&priv->lock);
328 }
329 
330 static int encx24j600_receive_packet(struct encx24j600_priv *priv,
331 				     struct rsv *rsv)
332 {
333 	struct net_device *dev = priv->ndev;
334 	struct sk_buff *skb = netdev_alloc_skb(dev, rsv->len + NET_IP_ALIGN);
335 
336 	if (!skb) {
337 		pr_err_ratelimited("RX: OOM: packet dropped\n");
338 		dev->stats.rx_dropped++;
339 		return -ENOMEM;
340 	}
341 	skb_reserve(skb, NET_IP_ALIGN);
342 	encx24j600_raw_read(priv, RRXDATA, skb_put(skb, rsv->len), rsv->len);
343 
344 	if (netif_msg_pktdata(priv))
345 		dump_packet("RX", skb->len, skb->data);
346 
347 	skb->dev = dev;
348 	skb->protocol = eth_type_trans(skb, dev);
349 	skb->ip_summed = CHECKSUM_COMPLETE;
350 
351 	/* Maintain stats */
352 	dev->stats.rx_packets++;
353 	dev->stats.rx_bytes += rsv->len;
354 
355 	netif_rx(skb);
356 
357 	return 0;
358 }
359 
360 static void encx24j600_rx_packets(struct encx24j600_priv *priv, u8 packet_count)
361 {
362 	struct net_device *dev = priv->ndev;
363 
364 	while (packet_count--) {
365 		struct rsv rsv;
366 		u16 newrxtail;
367 
368 		encx24j600_write_reg(priv, ERXRDPT, priv->next_packet);
369 		encx24j600_raw_read(priv, RRXDATA, (u8 *)&rsv, sizeof(rsv));
370 
371 		if (netif_msg_rx_status(priv))
372 			encx24j600_dump_rsv(priv, __func__, &rsv);
373 
374 		if (!RSV_GETBIT(rsv.rxstat, RSV_RXOK) ||
375 		    (rsv.len > MAX_FRAMELEN)) {
376 			netif_err(priv, rx_err, dev, "RX Error %04x\n",
377 				  rsv.rxstat);
378 			dev->stats.rx_errors++;
379 
380 			if (RSV_GETBIT(rsv.rxstat, RSV_CRCERROR))
381 				dev->stats.rx_crc_errors++;
382 			if (RSV_GETBIT(rsv.rxstat, RSV_LENCHECKERR))
383 				dev->stats.rx_frame_errors++;
384 			if (rsv.len > MAX_FRAMELEN)
385 				dev->stats.rx_over_errors++;
386 		} else {
387 			encx24j600_receive_packet(priv, &rsv);
388 		}
389 
390 		priv->next_packet = rsv.next_packet;
391 
392 		newrxtail = priv->next_packet - 2;
393 		if (newrxtail == ENC_RX_BUF_START)
394 			newrxtail = SRAM_SIZE - 2;
395 
396 		encx24j600_cmd(priv, SETPKTDEC);
397 		encx24j600_write_reg(priv, ERXTAIL, newrxtail);
398 	}
399 }
400 
401 static irqreturn_t encx24j600_isr(int irq, void *dev_id)
402 {
403 	struct encx24j600_priv *priv = dev_id;
404 	struct net_device *dev = priv->ndev;
405 	int eir;
406 
407 	/* Clear interrupts */
408 	encx24j600_cmd(priv, CLREIE);
409 
410 	eir = encx24j600_read_reg(priv, EIR);
411 
412 	if (eir & LINKIF)
413 		encx24j600_int_link_handler(priv);
414 
415 	if (eir & TXIF)
416 		encx24j600_tx_complete(priv, false);
417 
418 	if (eir & TXABTIF)
419 		encx24j600_tx_complete(priv, true);
420 
421 	if (eir & RXABTIF) {
422 		if (eir & PCFULIF) {
423 			/* Packet counter is full */
424 			netif_err(priv, rx_err, dev, "Packet counter full\n");
425 		}
426 		dev->stats.rx_dropped++;
427 		encx24j600_clr_bits(priv, EIR, RXABTIF);
428 	}
429 
430 	if (eir & PKTIF) {
431 		u8 packet_count;
432 
433 		mutex_lock(&priv->lock);
434 
435 		packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
436 		while (packet_count) {
437 			encx24j600_rx_packets(priv, packet_count);
438 			packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
439 		}
440 
441 		mutex_unlock(&priv->lock);
442 	}
443 
444 	/* Enable interrupts */
445 	encx24j600_cmd(priv, SETEIE);
446 
447 	return IRQ_HANDLED;
448 }
449 
450 static int encx24j600_soft_reset(struct encx24j600_priv *priv)
451 {
452 	int ret = 0;
453 	int timeout;
454 	u16 eudast;
455 
456 	/* Write and verify a test value to EUDAST */
457 	regcache_cache_bypass(priv->ctx.regmap, true);
458 	timeout = 10;
459 	do {
460 		encx24j600_write_reg(priv, EUDAST, EUDAST_TEST_VAL);
461 		eudast = encx24j600_read_reg(priv, EUDAST);
462 		usleep_range(25, 100);
463 	} while ((eudast != EUDAST_TEST_VAL) && --timeout);
464 	regcache_cache_bypass(priv->ctx.regmap, false);
465 
466 	if (timeout == 0) {
467 		ret = -ETIMEDOUT;
468 		goto err_out;
469 	}
470 
471 	/* Wait for CLKRDY to become set */
472 	timeout = 10;
473 	while (!(encx24j600_read_reg(priv, ESTAT) & CLKRDY) && --timeout)
474 		usleep_range(25, 100);
475 
476 	if (timeout == 0) {
477 		ret = -ETIMEDOUT;
478 		goto err_out;
479 	}
480 
481 	/* Issue a System Reset command */
482 	encx24j600_cmd(priv, SETETHRST);
483 	usleep_range(25, 100);
484 
485 	/* Confirm that EUDAST has 0000h after system reset */
486 	if (encx24j600_read_reg(priv, EUDAST) != 0) {
487 		ret = -EINVAL;
488 		goto err_out;
489 	}
490 
491 	/* Wait for PHY register and status bits to become available */
492 	usleep_range(256, 1000);
493 
494 err_out:
495 	return ret;
496 }
497 
498 static int encx24j600_hw_reset(struct encx24j600_priv *priv)
499 {
500 	int ret;
501 
502 	mutex_lock(&priv->lock);
503 	ret = encx24j600_soft_reset(priv);
504 	mutex_unlock(&priv->lock);
505 
506 	return ret;
507 }
508 
509 static void encx24j600_reset_hw_tx(struct encx24j600_priv *priv)
510 {
511 	encx24j600_set_bits(priv, ECON2, TXRST);
512 	encx24j600_clr_bits(priv, ECON2, TXRST);
513 }
514 
515 static void encx24j600_hw_init_tx(struct encx24j600_priv *priv)
516 {
517 	/* Reset TX */
518 	encx24j600_reset_hw_tx(priv);
519 
520 	/* Clear the TXIF flag if were previously set */
521 	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
522 
523 	/* Write the Tx Buffer pointer */
524 	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
525 }
526 
527 static void encx24j600_hw_init_rx(struct encx24j600_priv *priv)
528 {
529 	encx24j600_cmd(priv, DISABLERX);
530 
531 	/* Set up RX packet start address in the SRAM */
532 	encx24j600_write_reg(priv, ERXST, ENC_RX_BUF_START);
533 
534 	/* Preload the RX Data pointer to the beginning of the RX area */
535 	encx24j600_write_reg(priv, ERXRDPT, ENC_RX_BUF_START);
536 
537 	priv->next_packet = ENC_RX_BUF_START;
538 
539 	/* Set up RX end address in the SRAM */
540 	encx24j600_write_reg(priv, ERXTAIL, ENC_SRAM_SIZE - 2);
541 
542 	/* Reset the  user data pointers    */
543 	encx24j600_write_reg(priv, EUDAST, ENC_SRAM_SIZE);
544 	encx24j600_write_reg(priv, EUDAND, ENC_SRAM_SIZE + 1);
545 
546 	/* Set Max Frame length */
547 	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
548 }
549 
550 static void encx24j600_dump_config(struct encx24j600_priv *priv,
551 				   const char *msg)
552 {
553 	pr_info(DRV_NAME ": %s\n", msg);
554 
555 	/* CHIP configuration */
556 	pr_info(DRV_NAME " ECON1:   %04X\n", encx24j600_read_reg(priv, ECON1));
557 	pr_info(DRV_NAME " ECON2:   %04X\n", encx24j600_read_reg(priv, ECON2));
558 	pr_info(DRV_NAME " ERXFCON: %04X\n", encx24j600_read_reg(priv,
559 								 ERXFCON));
560 	pr_info(DRV_NAME " ESTAT:   %04X\n", encx24j600_read_reg(priv, ESTAT));
561 	pr_info(DRV_NAME " EIR:     %04X\n", encx24j600_read_reg(priv, EIR));
562 	pr_info(DRV_NAME " EIDLED:  %04X\n", encx24j600_read_reg(priv, EIDLED));
563 
564 	/* MAC layer configuration */
565 	pr_info(DRV_NAME " MACON1:  %04X\n", encx24j600_read_reg(priv, MACON1));
566 	pr_info(DRV_NAME " MACON2:  %04X\n", encx24j600_read_reg(priv, MACON2));
567 	pr_info(DRV_NAME " MAIPG:   %04X\n", encx24j600_read_reg(priv, MAIPG));
568 	pr_info(DRV_NAME " MACLCON: %04X\n", encx24j600_read_reg(priv,
569 								 MACLCON));
570 	pr_info(DRV_NAME " MABBIPG: %04X\n", encx24j600_read_reg(priv,
571 								 MABBIPG));
572 
573 	/* PHY configuation */
574 	pr_info(DRV_NAME " PHCON1:  %04X\n", encx24j600_read_phy(priv, PHCON1));
575 	pr_info(DRV_NAME " PHCON2:  %04X\n", encx24j600_read_phy(priv, PHCON2));
576 	pr_info(DRV_NAME " PHANA:   %04X\n", encx24j600_read_phy(priv, PHANA));
577 	pr_info(DRV_NAME " PHANLPA: %04X\n", encx24j600_read_phy(priv,
578 								 PHANLPA));
579 	pr_info(DRV_NAME " PHANE:   %04X\n", encx24j600_read_phy(priv, PHANE));
580 	pr_info(DRV_NAME " PHSTAT1: %04X\n", encx24j600_read_phy(priv,
581 								 PHSTAT1));
582 	pr_info(DRV_NAME " PHSTAT2: %04X\n", encx24j600_read_phy(priv,
583 								 PHSTAT2));
584 	pr_info(DRV_NAME " PHSTAT3: %04X\n", encx24j600_read_phy(priv,
585 								 PHSTAT3));
586 }
587 
588 static void encx24j600_set_rxfilter_mode(struct encx24j600_priv *priv)
589 {
590 	switch (priv->rxfilter) {
591 	case RXFILTER_PROMISC:
592 		encx24j600_set_bits(priv, MACON1, PASSALL);
593 		encx24j600_write_reg(priv, ERXFCON, UCEN | MCEN | NOTMEEN);
594 		break;
595 	case RXFILTER_MULTI:
596 		encx24j600_clr_bits(priv, MACON1, PASSALL);
597 		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN | MCEN);
598 		break;
599 	case RXFILTER_NORMAL:
600 	default:
601 		encx24j600_clr_bits(priv, MACON1, PASSALL);
602 		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN);
603 		break;
604 	}
605 }
606 
607 static int encx24j600_hw_init(struct encx24j600_priv *priv)
608 {
609 	int ret = 0;
610 	u16 macon2;
611 
612 	priv->hw_enabled = false;
613 
614 	/* PHY Leds: link status,
615 	 * LEDA: Link State + collision events
616 	 * LEDB: Link State + transmit/receive events
617 	 */
618 	encx24j600_update_reg(priv, EIDLED, 0xff00, 0xcb00);
619 
620 	/* Loopback disabled */
621 	encx24j600_write_reg(priv, MACON1, 0x9);
622 
623 	/* interpacket gap value */
624 	encx24j600_write_reg(priv, MAIPG, 0x0c12);
625 
626 	/* Write the auto negotiation pattern */
627 	encx24j600_write_phy(priv, PHANA, PHANA_DEFAULT);
628 
629 	encx24j600_update_phcon1(priv);
630 	encx24j600_check_link_status(priv);
631 
632 	macon2 = MACON2_RSV1 | TXCRCEN | PADCFG0 | PADCFG2 | MACON2_DEFER;
633 	if ((priv->autoneg == AUTONEG_DISABLE) && priv->full_duplex)
634 		macon2 |= FULDPX;
635 
636 	encx24j600_set_bits(priv, MACON2, macon2);
637 
638 	priv->rxfilter = RXFILTER_NORMAL;
639 	encx24j600_set_rxfilter_mode(priv);
640 
641 	/* Program the Maximum frame length */
642 	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
643 
644 	/* Init Tx pointers */
645 	encx24j600_hw_init_tx(priv);
646 
647 	/* Init Rx pointers */
648 	encx24j600_hw_init_rx(priv);
649 
650 	if (netif_msg_hw(priv))
651 		encx24j600_dump_config(priv, "Hw is initialized");
652 
653 	return ret;
654 }
655 
656 static void encx24j600_hw_enable(struct encx24j600_priv *priv)
657 {
658 	/* Clear the interrupt flags in case was set */
659 	encx24j600_clr_bits(priv, EIR, (PCFULIF | RXABTIF | TXABTIF | TXIF |
660 					PKTIF | LINKIF));
661 
662 	/* Enable the interrupts */
663 	encx24j600_write_reg(priv, EIE, (PCFULIE | RXABTIE | TXABTIE | TXIE |
664 					 PKTIE | LINKIE | INTIE));
665 
666 	/* Enable RX */
667 	encx24j600_cmd(priv, ENABLERX);
668 
669 	priv->hw_enabled = true;
670 }
671 
672 static void encx24j600_hw_disable(struct encx24j600_priv *priv)
673 {
674 	/* Disable all interrupts */
675 	encx24j600_write_reg(priv, EIE, 0);
676 
677 	/* Disable RX */
678 	encx24j600_cmd(priv, DISABLERX);
679 
680 	priv->hw_enabled = false;
681 }
682 
683 static int encx24j600_setlink(struct net_device *dev, u8 autoneg, u16 speed,
684 			      u8 duplex)
685 {
686 	struct encx24j600_priv *priv = netdev_priv(dev);
687 	int ret = 0;
688 
689 	if (!priv->hw_enabled) {
690 		/* link is in low power mode now; duplex setting
691 		 * will take effect on next encx24j600_hw_init()
692 		 */
693 		if (speed == SPEED_10 || speed == SPEED_100) {
694 			priv->autoneg = (autoneg == AUTONEG_ENABLE);
695 			priv->full_duplex = (duplex == DUPLEX_FULL);
696 			priv->speed = (speed == SPEED_100);
697 		} else {
698 			netif_warn(priv, link, dev, "unsupported link speed setting\n");
699 			/*speeds other than SPEED_10 and SPEED_100 */
700 			/*are not supported by chip */
701 			ret = -EOPNOTSUPP;
702 		}
703 	} else {
704 		netif_warn(priv, link, dev, "Warning: hw must be disabled to set link mode\n");
705 		ret = -EBUSY;
706 	}
707 	return ret;
708 }
709 
710 static void encx24j600_hw_get_macaddr(struct encx24j600_priv *priv,
711 				      unsigned char *ethaddr)
712 {
713 	unsigned short val;
714 
715 	val = encx24j600_read_reg(priv, MAADR1);
716 
717 	ethaddr[0] = val & 0x00ff;
718 	ethaddr[1] = (val & 0xff00) >> 8;
719 
720 	val = encx24j600_read_reg(priv, MAADR2);
721 
722 	ethaddr[2] = val & 0x00ffU;
723 	ethaddr[3] = (val & 0xff00U) >> 8;
724 
725 	val = encx24j600_read_reg(priv, MAADR3);
726 
727 	ethaddr[4] = val & 0x00ffU;
728 	ethaddr[5] = (val & 0xff00U) >> 8;
729 }
730 
731 /* Program the hardware MAC address from dev->dev_addr.*/
732 static int encx24j600_set_hw_macaddr(struct net_device *dev)
733 {
734 	struct encx24j600_priv *priv = netdev_priv(dev);
735 
736 	if (priv->hw_enabled) {
737 		netif_info(priv, drv, dev, "Hardware must be disabled to set Mac address\n");
738 		return -EBUSY;
739 	}
740 
741 	mutex_lock(&priv->lock);
742 
743 	netif_info(priv, drv, dev, "%s: Setting MAC address to %pM\n",
744 		   dev->name, dev->dev_addr);
745 
746 	encx24j600_write_reg(priv, MAADR3, (dev->dev_addr[4] |
747 			     dev->dev_addr[5] << 8));
748 	encx24j600_write_reg(priv, MAADR2, (dev->dev_addr[2] |
749 			     dev->dev_addr[3] << 8));
750 	encx24j600_write_reg(priv, MAADR1, (dev->dev_addr[0] |
751 			     dev->dev_addr[1] << 8));
752 
753 	mutex_unlock(&priv->lock);
754 
755 	return 0;
756 }
757 
758 /* Store the new hardware address in dev->dev_addr, and update the MAC.*/
759 static int encx24j600_set_mac_address(struct net_device *dev, void *addr)
760 {
761 	struct sockaddr *address = addr;
762 
763 	if (netif_running(dev))
764 		return -EBUSY;
765 	if (!is_valid_ether_addr(address->sa_data))
766 		return -EADDRNOTAVAIL;
767 
768 	memcpy(dev->dev_addr, address->sa_data, dev->addr_len);
769 	return encx24j600_set_hw_macaddr(dev);
770 }
771 
772 static int encx24j600_open(struct net_device *dev)
773 {
774 	struct encx24j600_priv *priv = netdev_priv(dev);
775 
776 	int ret = request_threaded_irq(priv->ctx.spi->irq, NULL, encx24j600_isr,
777 				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
778 				       DRV_NAME, priv);
779 	if (unlikely(ret < 0)) {
780 		netdev_err(dev, "request irq %d failed (ret = %d)\n",
781 			   priv->ctx.spi->irq, ret);
782 		return ret;
783 	}
784 
785 	encx24j600_hw_disable(priv);
786 	encx24j600_hw_init(priv);
787 	encx24j600_hw_enable(priv);
788 	netif_start_queue(dev);
789 
790 	return 0;
791 }
792 
793 static int encx24j600_stop(struct net_device *dev)
794 {
795 	struct encx24j600_priv *priv = netdev_priv(dev);
796 
797 	netif_stop_queue(dev);
798 	free_irq(priv->ctx.spi->irq, priv);
799 	return 0;
800 }
801 
802 static void encx24j600_setrx_proc(struct kthread_work *ws)
803 {
804 	struct encx24j600_priv *priv =
805 			container_of(ws, struct encx24j600_priv, setrx_work);
806 
807 	mutex_lock(&priv->lock);
808 	encx24j600_set_rxfilter_mode(priv);
809 	mutex_unlock(&priv->lock);
810 }
811 
812 static void encx24j600_set_multicast_list(struct net_device *dev)
813 {
814 	struct encx24j600_priv *priv = netdev_priv(dev);
815 	int oldfilter = priv->rxfilter;
816 
817 	if (dev->flags & IFF_PROMISC) {
818 		netif_dbg(priv, link, dev, "promiscuous mode\n");
819 		priv->rxfilter = RXFILTER_PROMISC;
820 	} else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev)) {
821 		netif_dbg(priv, link, dev, "%smulticast mode\n",
822 			  (dev->flags & IFF_ALLMULTI) ? "all-" : "");
823 		priv->rxfilter = RXFILTER_MULTI;
824 	} else {
825 		netif_dbg(priv, link, dev, "normal mode\n");
826 		priv->rxfilter = RXFILTER_NORMAL;
827 	}
828 
829 	if (oldfilter != priv->rxfilter)
830 		kthread_queue_work(&priv->kworker, &priv->setrx_work);
831 }
832 
833 static void encx24j600_hw_tx(struct encx24j600_priv *priv)
834 {
835 	struct net_device *dev = priv->ndev;
836 
837 	netif_info(priv, tx_queued, dev, "TX Packet Len:%d\n",
838 		   priv->tx_skb->len);
839 
840 	if (netif_msg_pktdata(priv))
841 		dump_packet("TX", priv->tx_skb->len, priv->tx_skb->data);
842 
843 	if (encx24j600_read_reg(priv, EIR) & TXABTIF)
844 		/* Last transmition aborted due to error. Reset TX interface */
845 		encx24j600_reset_hw_tx(priv);
846 
847 	/* Clear the TXIF flag if were previously set */
848 	encx24j600_clr_bits(priv, EIR, TXIF);
849 
850 	/* Set the data pointer to the TX buffer address in the SRAM */
851 	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
852 
853 	/* Copy the packet into the SRAM */
854 	encx24j600_raw_write(priv, WGPDATA, (u8 *)priv->tx_skb->data,
855 			     priv->tx_skb->len);
856 
857 	/* Program the Tx buffer start pointer */
858 	encx24j600_write_reg(priv, ETXST, ENC_TX_BUF_START);
859 
860 	/* Program the packet length */
861 	encx24j600_write_reg(priv, ETXLEN, priv->tx_skb->len);
862 
863 	/* Start the transmission */
864 	encx24j600_cmd(priv, SETTXRTS);
865 }
866 
867 static void encx24j600_tx_proc(struct kthread_work *ws)
868 {
869 	struct encx24j600_priv *priv =
870 			container_of(ws, struct encx24j600_priv, tx_work);
871 
872 	mutex_lock(&priv->lock);
873 	encx24j600_hw_tx(priv);
874 	mutex_unlock(&priv->lock);
875 }
876 
877 static netdev_tx_t encx24j600_tx(struct sk_buff *skb, struct net_device *dev)
878 {
879 	struct encx24j600_priv *priv = netdev_priv(dev);
880 
881 	netif_stop_queue(dev);
882 
883 	/* save the timestamp */
884 	netif_trans_update(dev);
885 
886 	/* Remember the skb for deferred processing */
887 	priv->tx_skb = skb;
888 
889 	kthread_queue_work(&priv->kworker, &priv->tx_work);
890 
891 	return NETDEV_TX_OK;
892 }
893 
894 /* Deal with a transmit timeout */
895 static void encx24j600_tx_timeout(struct net_device *dev, unsigned int txqueue)
896 {
897 	struct encx24j600_priv *priv = netdev_priv(dev);
898 
899 	netif_err(priv, tx_err, dev, "TX timeout at %ld, latency %ld\n",
900 		  jiffies, jiffies - dev_trans_start(dev));
901 
902 	dev->stats.tx_errors++;
903 	netif_wake_queue(dev);
904 }
905 
906 static int encx24j600_get_regs_len(struct net_device *dev)
907 {
908 	return SFR_REG_COUNT;
909 }
910 
911 static void encx24j600_get_regs(struct net_device *dev,
912 				struct ethtool_regs *regs, void *p)
913 {
914 	struct encx24j600_priv *priv = netdev_priv(dev);
915 	u16 *buff = p;
916 	u8 reg;
917 
918 	regs->version = 1;
919 	mutex_lock(&priv->lock);
920 	for (reg = 0; reg < SFR_REG_COUNT; reg += 2) {
921 		unsigned int val = 0;
922 		/* ignore errors for unreadable registers */
923 		regmap_read(priv->ctx.regmap, reg, &val);
924 		buff[reg] = val & 0xffff;
925 	}
926 	mutex_unlock(&priv->lock);
927 }
928 
929 static void encx24j600_get_drvinfo(struct net_device *dev,
930 				   struct ethtool_drvinfo *info)
931 {
932 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
933 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
934 	strlcpy(info->bus_info, dev_name(dev->dev.parent),
935 		sizeof(info->bus_info));
936 }
937 
938 static int encx24j600_get_link_ksettings(struct net_device *dev,
939 					 struct ethtool_link_ksettings *cmd)
940 {
941 	struct encx24j600_priv *priv = netdev_priv(dev);
942 	u32 supported;
943 
944 	supported = SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full |
945 			 SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full |
946 			 SUPPORTED_Autoneg | SUPPORTED_TP;
947 
948 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
949 						supported);
950 
951 	cmd->base.speed = priv->speed;
952 	cmd->base.duplex = priv->full_duplex ? DUPLEX_FULL : DUPLEX_HALF;
953 	cmd->base.port = PORT_TP;
954 	cmd->base.autoneg = priv->autoneg ? AUTONEG_ENABLE : AUTONEG_DISABLE;
955 
956 	return 0;
957 }
958 
959 static int
960 encx24j600_set_link_ksettings(struct net_device *dev,
961 			      const struct ethtool_link_ksettings *cmd)
962 {
963 	return encx24j600_setlink(dev, cmd->base.autoneg,
964 				  cmd->base.speed, cmd->base.duplex);
965 }
966 
967 static u32 encx24j600_get_msglevel(struct net_device *dev)
968 {
969 	struct encx24j600_priv *priv = netdev_priv(dev);
970 
971 	return priv->msg_enable;
972 }
973 
974 static void encx24j600_set_msglevel(struct net_device *dev, u32 val)
975 {
976 	struct encx24j600_priv *priv = netdev_priv(dev);
977 
978 	priv->msg_enable = val;
979 }
980 
981 static const struct ethtool_ops encx24j600_ethtool_ops = {
982 	.get_drvinfo = encx24j600_get_drvinfo,
983 	.get_msglevel = encx24j600_get_msglevel,
984 	.set_msglevel = encx24j600_set_msglevel,
985 	.get_regs_len = encx24j600_get_regs_len,
986 	.get_regs = encx24j600_get_regs,
987 	.get_link_ksettings = encx24j600_get_link_ksettings,
988 	.set_link_ksettings = encx24j600_set_link_ksettings,
989 };
990 
991 static const struct net_device_ops encx24j600_netdev_ops = {
992 	.ndo_open = encx24j600_open,
993 	.ndo_stop = encx24j600_stop,
994 	.ndo_start_xmit = encx24j600_tx,
995 	.ndo_set_rx_mode = encx24j600_set_multicast_list,
996 	.ndo_set_mac_address = encx24j600_set_mac_address,
997 	.ndo_tx_timeout = encx24j600_tx_timeout,
998 	.ndo_validate_addr = eth_validate_addr,
999 };
1000 
1001 static int encx24j600_spi_probe(struct spi_device *spi)
1002 {
1003 	int ret;
1004 
1005 	struct net_device *ndev;
1006 	struct encx24j600_priv *priv;
1007 	u16 eidled;
1008 
1009 	ndev = alloc_etherdev(sizeof(struct encx24j600_priv));
1010 
1011 	if (!ndev) {
1012 		ret = -ENOMEM;
1013 		goto error_out;
1014 	}
1015 
1016 	priv = netdev_priv(ndev);
1017 	spi_set_drvdata(spi, priv);
1018 	dev_set_drvdata(&spi->dev, priv);
1019 	SET_NETDEV_DEV(ndev, &spi->dev);
1020 
1021 	priv->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);
1022 	priv->ndev = ndev;
1023 
1024 	/* Default configuration PHY configuration */
1025 	priv->full_duplex = true;
1026 	priv->autoneg = AUTONEG_ENABLE;
1027 	priv->speed = SPEED_100;
1028 
1029 	priv->ctx.spi = spi;
1030 	devm_regmap_init_encx24j600(&spi->dev, &priv->ctx);
1031 	ndev->irq = spi->irq;
1032 	ndev->netdev_ops = &encx24j600_netdev_ops;
1033 
1034 	mutex_init(&priv->lock);
1035 
1036 	/* Reset device and check if it is connected */
1037 	if (encx24j600_hw_reset(priv)) {
1038 		netif_err(priv, probe, ndev,
1039 			  DRV_NAME ": Chip is not detected\n");
1040 		ret = -EIO;
1041 		goto out_free;
1042 	}
1043 
1044 	/* Initialize the device HW to the consistent state */
1045 	if (encx24j600_hw_init(priv)) {
1046 		netif_err(priv, probe, ndev,
1047 			  DRV_NAME ": HW initialization error\n");
1048 		ret = -EIO;
1049 		goto out_free;
1050 	}
1051 
1052 	kthread_init_worker(&priv->kworker);
1053 	kthread_init_work(&priv->tx_work, encx24j600_tx_proc);
1054 	kthread_init_work(&priv->setrx_work, encx24j600_setrx_proc);
1055 
1056 	priv->kworker_task = kthread_run(kthread_worker_fn, &priv->kworker,
1057 					 "encx24j600");
1058 
1059 	if (IS_ERR(priv->kworker_task)) {
1060 		ret = PTR_ERR(priv->kworker_task);
1061 		goto out_free;
1062 	}
1063 
1064 	/* Get the MAC address from the chip */
1065 	encx24j600_hw_get_macaddr(priv, ndev->dev_addr);
1066 
1067 	ndev->ethtool_ops = &encx24j600_ethtool_ops;
1068 
1069 	ret = register_netdev(ndev);
1070 	if (unlikely(ret)) {
1071 		netif_err(priv, probe, ndev, "Error %d initializing card encx24j600 card\n",
1072 			  ret);
1073 		goto out_free;
1074 	}
1075 
1076 	eidled = encx24j600_read_reg(priv, EIDLED);
1077 	if (((eidled & DEVID_MASK) >> DEVID_SHIFT) != ENCX24J600_DEV_ID) {
1078 		ret = -EINVAL;
1079 		goto out_unregister;
1080 	}
1081 
1082 	netif_info(priv, probe, ndev, "Silicon rev ID: 0x%02x\n",
1083 		   (eidled & REVID_MASK) >> REVID_SHIFT);
1084 
1085 	netif_info(priv, drv, priv->ndev, "MAC address %pM\n", ndev->dev_addr);
1086 
1087 	return ret;
1088 
1089 out_unregister:
1090 	unregister_netdev(priv->ndev);
1091 out_free:
1092 	free_netdev(ndev);
1093 
1094 error_out:
1095 	return ret;
1096 }
1097 
1098 static int encx24j600_spi_remove(struct spi_device *spi)
1099 {
1100 	struct encx24j600_priv *priv = dev_get_drvdata(&spi->dev);
1101 
1102 	unregister_netdev(priv->ndev);
1103 
1104 	free_netdev(priv->ndev);
1105 
1106 	return 0;
1107 }
1108 
1109 static const struct spi_device_id encx24j600_spi_id_table[] = {
1110 	{ .name = "encx24j600" },
1111 	{ /* sentinel */ }
1112 };
1113 MODULE_DEVICE_TABLE(spi, encx24j600_spi_id_table);
1114 
1115 static struct spi_driver encx24j600_spi_net_driver = {
1116 	.driver = {
1117 		.name	= DRV_NAME,
1118 		.owner	= THIS_MODULE,
1119 		.bus	= &spi_bus_type,
1120 	},
1121 	.probe		= encx24j600_spi_probe,
1122 	.remove		= encx24j600_spi_remove,
1123 	.id_table	= encx24j600_spi_id_table,
1124 };
1125 
1126 static int __init encx24j600_init(void)
1127 {
1128 	return spi_register_driver(&encx24j600_spi_net_driver);
1129 }
1130 module_init(encx24j600_init);
1131 
1132 static void encx24j600_exit(void)
1133 {
1134 	spi_unregister_driver(&encx24j600_spi_net_driver);
1135 }
1136 module_exit(encx24j600_exit);
1137 
1138 MODULE_DESCRIPTION(DRV_NAME " ethernet driver");
1139 MODULE_AUTHOR("Jon Ringle <jringle@gridpoint.com>");
1140 MODULE_LICENSE("GPL");
1141 MODULE_ALIAS("spi:" DRV_NAME);
1142