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