xref: /linux/drivers/net/phy/sfp.c (revision 44f57d78)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/ctype.h>
3 #include <linux/delay.h>
4 #include <linux/gpio/consumer.h>
5 #include <linux/hwmon.h>
6 #include <linux/i2c.h>
7 #include <linux/interrupt.h>
8 #include <linux/jiffies.h>
9 #include <linux/module.h>
10 #include <linux/mutex.h>
11 #include <linux/of.h>
12 #include <linux/phy.h>
13 #include <linux/platform_device.h>
14 #include <linux/rtnetlink.h>
15 #include <linux/slab.h>
16 #include <linux/workqueue.h>
17 
18 #include "mdio-i2c.h"
19 #include "sfp.h"
20 #include "swphy.h"
21 
22 enum {
23 	GPIO_MODDEF0,
24 	GPIO_LOS,
25 	GPIO_TX_FAULT,
26 	GPIO_TX_DISABLE,
27 	GPIO_RATE_SELECT,
28 	GPIO_MAX,
29 
30 	SFP_F_PRESENT = BIT(GPIO_MODDEF0),
31 	SFP_F_LOS = BIT(GPIO_LOS),
32 	SFP_F_TX_FAULT = BIT(GPIO_TX_FAULT),
33 	SFP_F_TX_DISABLE = BIT(GPIO_TX_DISABLE),
34 	SFP_F_RATE_SELECT = BIT(GPIO_RATE_SELECT),
35 
36 	SFP_E_INSERT = 0,
37 	SFP_E_REMOVE,
38 	SFP_E_DEV_DOWN,
39 	SFP_E_DEV_UP,
40 	SFP_E_TX_FAULT,
41 	SFP_E_TX_CLEAR,
42 	SFP_E_LOS_HIGH,
43 	SFP_E_LOS_LOW,
44 	SFP_E_TIMEOUT,
45 
46 	SFP_MOD_EMPTY = 0,
47 	SFP_MOD_PROBE,
48 	SFP_MOD_HPOWER,
49 	SFP_MOD_PRESENT,
50 	SFP_MOD_ERROR,
51 
52 	SFP_DEV_DOWN = 0,
53 	SFP_DEV_UP,
54 
55 	SFP_S_DOWN = 0,
56 	SFP_S_INIT,
57 	SFP_S_WAIT_LOS,
58 	SFP_S_LINK_UP,
59 	SFP_S_TX_FAULT,
60 	SFP_S_REINIT,
61 	SFP_S_TX_DISABLE,
62 };
63 
64 static const char  * const mod_state_strings[] = {
65 	[SFP_MOD_EMPTY] = "empty",
66 	[SFP_MOD_PROBE] = "probe",
67 	[SFP_MOD_HPOWER] = "hpower",
68 	[SFP_MOD_PRESENT] = "present",
69 	[SFP_MOD_ERROR] = "error",
70 };
71 
72 static const char *mod_state_to_str(unsigned short mod_state)
73 {
74 	if (mod_state >= ARRAY_SIZE(mod_state_strings))
75 		return "Unknown module state";
76 	return mod_state_strings[mod_state];
77 }
78 
79 static const char * const dev_state_strings[] = {
80 	[SFP_DEV_DOWN] = "down",
81 	[SFP_DEV_UP] = "up",
82 };
83 
84 static const char *dev_state_to_str(unsigned short dev_state)
85 {
86 	if (dev_state >= ARRAY_SIZE(dev_state_strings))
87 		return "Unknown device state";
88 	return dev_state_strings[dev_state];
89 }
90 
91 static const char * const event_strings[] = {
92 	[SFP_E_INSERT] = "insert",
93 	[SFP_E_REMOVE] = "remove",
94 	[SFP_E_DEV_DOWN] = "dev_down",
95 	[SFP_E_DEV_UP] = "dev_up",
96 	[SFP_E_TX_FAULT] = "tx_fault",
97 	[SFP_E_TX_CLEAR] = "tx_clear",
98 	[SFP_E_LOS_HIGH] = "los_high",
99 	[SFP_E_LOS_LOW] = "los_low",
100 	[SFP_E_TIMEOUT] = "timeout",
101 };
102 
103 static const char *event_to_str(unsigned short event)
104 {
105 	if (event >= ARRAY_SIZE(event_strings))
106 		return "Unknown event";
107 	return event_strings[event];
108 }
109 
110 static const char * const sm_state_strings[] = {
111 	[SFP_S_DOWN] = "down",
112 	[SFP_S_INIT] = "init",
113 	[SFP_S_WAIT_LOS] = "wait_los",
114 	[SFP_S_LINK_UP] = "link_up",
115 	[SFP_S_TX_FAULT] = "tx_fault",
116 	[SFP_S_REINIT] = "reinit",
117 	[SFP_S_TX_DISABLE] = "rx_disable",
118 };
119 
120 static const char *sm_state_to_str(unsigned short sm_state)
121 {
122 	if (sm_state >= ARRAY_SIZE(sm_state_strings))
123 		return "Unknown state";
124 	return sm_state_strings[sm_state];
125 }
126 
127 static const char *gpio_of_names[] = {
128 	"mod-def0",
129 	"los",
130 	"tx-fault",
131 	"tx-disable",
132 	"rate-select0",
133 };
134 
135 static const enum gpiod_flags gpio_flags[] = {
136 	GPIOD_IN,
137 	GPIOD_IN,
138 	GPIOD_IN,
139 	GPIOD_ASIS,
140 	GPIOD_ASIS,
141 };
142 
143 #define T_INIT_JIFFIES	msecs_to_jiffies(300)
144 #define T_RESET_US	10
145 #define T_FAULT_RECOVER	msecs_to_jiffies(1000)
146 
147 /* SFP module presence detection is poor: the three MOD DEF signals are
148  * the same length on the PCB, which means it's possible for MOD DEF 0 to
149  * connect before the I2C bus on MOD DEF 1/2.
150  *
151  * The SFP MSA specifies 300ms as t_init (the time taken for TX_FAULT to
152  * be deasserted) but makes no mention of the earliest time before we can
153  * access the I2C EEPROM.  However, Avago modules require 300ms.
154  */
155 #define T_PROBE_INIT	msecs_to_jiffies(300)
156 #define T_HPOWER_LEVEL	msecs_to_jiffies(300)
157 #define T_PROBE_RETRY	msecs_to_jiffies(100)
158 
159 /* SFP modules appear to always have their PHY configured for bus address
160  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
161  */
162 #define SFP_PHY_ADDR	22
163 
164 /* Give this long for the PHY to reset. */
165 #define T_PHY_RESET_MS	50
166 
167 struct sff_data {
168 	unsigned int gpios;
169 	bool (*module_supported)(const struct sfp_eeprom_id *id);
170 };
171 
172 struct sfp {
173 	struct device *dev;
174 	struct i2c_adapter *i2c;
175 	struct mii_bus *i2c_mii;
176 	struct sfp_bus *sfp_bus;
177 	struct phy_device *mod_phy;
178 	const struct sff_data *type;
179 	u32 max_power_mW;
180 
181 	unsigned int (*get_state)(struct sfp *);
182 	void (*set_state)(struct sfp *, unsigned int);
183 	int (*read)(struct sfp *, bool, u8, void *, size_t);
184 	int (*write)(struct sfp *, bool, u8, void *, size_t);
185 
186 	struct gpio_desc *gpio[GPIO_MAX];
187 
188 	bool attached;
189 	unsigned int state;
190 	struct delayed_work poll;
191 	struct delayed_work timeout;
192 	struct mutex sm_mutex;
193 	unsigned char sm_mod_state;
194 	unsigned char sm_dev_state;
195 	unsigned short sm_state;
196 	unsigned int sm_retries;
197 
198 	struct sfp_eeprom_id id;
199 #if IS_ENABLED(CONFIG_HWMON)
200 	struct sfp_diag diag;
201 	struct device *hwmon_dev;
202 	char *hwmon_name;
203 #endif
204 
205 };
206 
207 static bool sff_module_supported(const struct sfp_eeprom_id *id)
208 {
209 	return id->base.phys_id == SFP_PHYS_ID_SFF &&
210 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
211 }
212 
213 static const struct sff_data sff_data = {
214 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
215 	.module_supported = sff_module_supported,
216 };
217 
218 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
219 {
220 	return id->base.phys_id == SFP_PHYS_ID_SFP &&
221 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
222 }
223 
224 static const struct sff_data sfp_data = {
225 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
226 		 SFP_F_TX_DISABLE | SFP_F_RATE_SELECT,
227 	.module_supported = sfp_module_supported,
228 };
229 
230 static const struct of_device_id sfp_of_match[] = {
231 	{ .compatible = "sff,sff", .data = &sff_data, },
232 	{ .compatible = "sff,sfp", .data = &sfp_data, },
233 	{ },
234 };
235 MODULE_DEVICE_TABLE(of, sfp_of_match);
236 
237 static unsigned long poll_jiffies;
238 
239 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
240 {
241 	unsigned int i, state, v;
242 
243 	for (i = state = 0; i < GPIO_MAX; i++) {
244 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
245 			continue;
246 
247 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
248 		if (v)
249 			state |= BIT(i);
250 	}
251 
252 	return state;
253 }
254 
255 static unsigned int sff_gpio_get_state(struct sfp *sfp)
256 {
257 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
258 }
259 
260 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
261 {
262 	if (state & SFP_F_PRESENT) {
263 		/* If the module is present, drive the signals */
264 		if (sfp->gpio[GPIO_TX_DISABLE])
265 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
266 					       state & SFP_F_TX_DISABLE);
267 		if (state & SFP_F_RATE_SELECT)
268 			gpiod_direction_output(sfp->gpio[GPIO_RATE_SELECT],
269 					       state & SFP_F_RATE_SELECT);
270 	} else {
271 		/* Otherwise, let them float to the pull-ups */
272 		if (sfp->gpio[GPIO_TX_DISABLE])
273 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
274 		if (state & SFP_F_RATE_SELECT)
275 			gpiod_direction_input(sfp->gpio[GPIO_RATE_SELECT]);
276 	}
277 }
278 
279 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
280 			size_t len)
281 {
282 	struct i2c_msg msgs[2];
283 	u8 bus_addr = a2 ? 0x51 : 0x50;
284 	size_t this_len;
285 	int ret;
286 
287 	msgs[0].addr = bus_addr;
288 	msgs[0].flags = 0;
289 	msgs[0].len = 1;
290 	msgs[0].buf = &dev_addr;
291 	msgs[1].addr = bus_addr;
292 	msgs[1].flags = I2C_M_RD;
293 	msgs[1].len = len;
294 	msgs[1].buf = buf;
295 
296 	while (len) {
297 		this_len = len;
298 		if (this_len > 16)
299 			this_len = 16;
300 
301 		msgs[1].len = this_len;
302 
303 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
304 		if (ret < 0)
305 			return ret;
306 
307 		if (ret != ARRAY_SIZE(msgs))
308 			break;
309 
310 		msgs[1].buf += this_len;
311 		dev_addr += this_len;
312 		len -= this_len;
313 	}
314 
315 	return msgs[1].buf - (u8 *)buf;
316 }
317 
318 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
319 	size_t len)
320 {
321 	struct i2c_msg msgs[1];
322 	u8 bus_addr = a2 ? 0x51 : 0x50;
323 	int ret;
324 
325 	msgs[0].addr = bus_addr;
326 	msgs[0].flags = 0;
327 	msgs[0].len = 1 + len;
328 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
329 	if (!msgs[0].buf)
330 		return -ENOMEM;
331 
332 	msgs[0].buf[0] = dev_addr;
333 	memcpy(&msgs[0].buf[1], buf, len);
334 
335 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
336 
337 	kfree(msgs[0].buf);
338 
339 	if (ret < 0)
340 		return ret;
341 
342 	return ret == ARRAY_SIZE(msgs) ? len : 0;
343 }
344 
345 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
346 {
347 	struct mii_bus *i2c_mii;
348 	int ret;
349 
350 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
351 		return -EINVAL;
352 
353 	sfp->i2c = i2c;
354 	sfp->read = sfp_i2c_read;
355 	sfp->write = sfp_i2c_write;
356 
357 	i2c_mii = mdio_i2c_alloc(sfp->dev, i2c);
358 	if (IS_ERR(i2c_mii))
359 		return PTR_ERR(i2c_mii);
360 
361 	i2c_mii->name = "SFP I2C Bus";
362 	i2c_mii->phy_mask = ~0;
363 
364 	ret = mdiobus_register(i2c_mii);
365 	if (ret < 0) {
366 		mdiobus_free(i2c_mii);
367 		return ret;
368 	}
369 
370 	sfp->i2c_mii = i2c_mii;
371 
372 	return 0;
373 }
374 
375 /* Interface */
376 static unsigned int sfp_get_state(struct sfp *sfp)
377 {
378 	return sfp->get_state(sfp);
379 }
380 
381 static void sfp_set_state(struct sfp *sfp, unsigned int state)
382 {
383 	sfp->set_state(sfp, state);
384 }
385 
386 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
387 {
388 	return sfp->read(sfp, a2, addr, buf, len);
389 }
390 
391 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
392 {
393 	return sfp->write(sfp, a2, addr, buf, len);
394 }
395 
396 static unsigned int sfp_check(void *buf, size_t len)
397 {
398 	u8 *p, check;
399 
400 	for (p = buf, check = 0; len; p++, len--)
401 		check += *p;
402 
403 	return check;
404 }
405 
406 /* hwmon */
407 #if IS_ENABLED(CONFIG_HWMON)
408 static umode_t sfp_hwmon_is_visible(const void *data,
409 				    enum hwmon_sensor_types type,
410 				    u32 attr, int channel)
411 {
412 	const struct sfp *sfp = data;
413 
414 	switch (type) {
415 	case hwmon_temp:
416 		switch (attr) {
417 		case hwmon_temp_min_alarm:
418 		case hwmon_temp_max_alarm:
419 		case hwmon_temp_lcrit_alarm:
420 		case hwmon_temp_crit_alarm:
421 		case hwmon_temp_min:
422 		case hwmon_temp_max:
423 		case hwmon_temp_lcrit:
424 		case hwmon_temp_crit:
425 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
426 				return 0;
427 			/* fall through */
428 		case hwmon_temp_input:
429 			return 0444;
430 		default:
431 			return 0;
432 		}
433 	case hwmon_in:
434 		switch (attr) {
435 		case hwmon_in_min_alarm:
436 		case hwmon_in_max_alarm:
437 		case hwmon_in_lcrit_alarm:
438 		case hwmon_in_crit_alarm:
439 		case hwmon_in_min:
440 		case hwmon_in_max:
441 		case hwmon_in_lcrit:
442 		case hwmon_in_crit:
443 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
444 				return 0;
445 			/* fall through */
446 		case hwmon_in_input:
447 			return 0444;
448 		default:
449 			return 0;
450 		}
451 	case hwmon_curr:
452 		switch (attr) {
453 		case hwmon_curr_min_alarm:
454 		case hwmon_curr_max_alarm:
455 		case hwmon_curr_lcrit_alarm:
456 		case hwmon_curr_crit_alarm:
457 		case hwmon_curr_min:
458 		case hwmon_curr_max:
459 		case hwmon_curr_lcrit:
460 		case hwmon_curr_crit:
461 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
462 				return 0;
463 			/* fall through */
464 		case hwmon_curr_input:
465 			return 0444;
466 		default:
467 			return 0;
468 		}
469 	case hwmon_power:
470 		/* External calibration of receive power requires
471 		 * floating point arithmetic. Doing that in the kernel
472 		 * is not easy, so just skip it. If the module does
473 		 * not require external calibration, we can however
474 		 * show receiver power, since FP is then not needed.
475 		 */
476 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
477 		    channel == 1)
478 			return 0;
479 		switch (attr) {
480 		case hwmon_power_min_alarm:
481 		case hwmon_power_max_alarm:
482 		case hwmon_power_lcrit_alarm:
483 		case hwmon_power_crit_alarm:
484 		case hwmon_power_min:
485 		case hwmon_power_max:
486 		case hwmon_power_lcrit:
487 		case hwmon_power_crit:
488 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
489 				return 0;
490 			/* fall through */
491 		case hwmon_power_input:
492 			return 0444;
493 		default:
494 			return 0;
495 		}
496 	default:
497 		return 0;
498 	}
499 }
500 
501 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
502 {
503 	__be16 val;
504 	int err;
505 
506 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
507 	if (err < 0)
508 		return err;
509 
510 	*value = be16_to_cpu(val);
511 
512 	return 0;
513 }
514 
515 static void sfp_hwmon_to_rx_power(long *value)
516 {
517 	*value = DIV_ROUND_CLOSEST(*value, 100);
518 }
519 
520 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
521 				long *value)
522 {
523 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
524 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
525 }
526 
527 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
528 {
529 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
530 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
531 
532 	if (*value >= 0x8000)
533 		*value -= 0x10000;
534 
535 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
536 }
537 
538 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
539 {
540 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
541 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
542 
543 	*value = DIV_ROUND_CLOSEST(*value, 10);
544 }
545 
546 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
547 {
548 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
549 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
550 
551 	*value = DIV_ROUND_CLOSEST(*value, 500);
552 }
553 
554 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
555 {
556 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
557 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
558 
559 	*value = DIV_ROUND_CLOSEST(*value, 10);
560 }
561 
562 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
563 {
564 	int err;
565 
566 	err = sfp_hwmon_read_sensor(sfp, reg, value);
567 	if (err < 0)
568 		return err;
569 
570 	sfp_hwmon_calibrate_temp(sfp, value);
571 
572 	return 0;
573 }
574 
575 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
576 {
577 	int err;
578 
579 	err = sfp_hwmon_read_sensor(sfp, reg, value);
580 	if (err < 0)
581 		return err;
582 
583 	sfp_hwmon_calibrate_vcc(sfp, value);
584 
585 	return 0;
586 }
587 
588 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
589 {
590 	int err;
591 
592 	err = sfp_hwmon_read_sensor(sfp, reg, value);
593 	if (err < 0)
594 		return err;
595 
596 	sfp_hwmon_calibrate_bias(sfp, value);
597 
598 	return 0;
599 }
600 
601 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
602 {
603 	int err;
604 
605 	err = sfp_hwmon_read_sensor(sfp, reg, value);
606 	if (err < 0)
607 		return err;
608 
609 	sfp_hwmon_calibrate_tx_power(sfp, value);
610 
611 	return 0;
612 }
613 
614 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
615 {
616 	int err;
617 
618 	err = sfp_hwmon_read_sensor(sfp, reg, value);
619 	if (err < 0)
620 		return err;
621 
622 	sfp_hwmon_to_rx_power(value);
623 
624 	return 0;
625 }
626 
627 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
628 {
629 	u8 status;
630 	int err;
631 
632 	switch (attr) {
633 	case hwmon_temp_input:
634 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
635 
636 	case hwmon_temp_lcrit:
637 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
638 		sfp_hwmon_calibrate_temp(sfp, value);
639 		return 0;
640 
641 	case hwmon_temp_min:
642 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
643 		sfp_hwmon_calibrate_temp(sfp, value);
644 		return 0;
645 	case hwmon_temp_max:
646 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
647 		sfp_hwmon_calibrate_temp(sfp, value);
648 		return 0;
649 
650 	case hwmon_temp_crit:
651 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
652 		sfp_hwmon_calibrate_temp(sfp, value);
653 		return 0;
654 
655 	case hwmon_temp_lcrit_alarm:
656 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
657 		if (err < 0)
658 			return err;
659 
660 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
661 		return 0;
662 
663 	case hwmon_temp_min_alarm:
664 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
665 		if (err < 0)
666 			return err;
667 
668 		*value = !!(status & SFP_WARN0_TEMP_LOW);
669 		return 0;
670 
671 	case hwmon_temp_max_alarm:
672 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
673 		if (err < 0)
674 			return err;
675 
676 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
677 		return 0;
678 
679 	case hwmon_temp_crit_alarm:
680 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
681 		if (err < 0)
682 			return err;
683 
684 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
685 		return 0;
686 	default:
687 		return -EOPNOTSUPP;
688 	}
689 
690 	return -EOPNOTSUPP;
691 }
692 
693 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
694 {
695 	u8 status;
696 	int err;
697 
698 	switch (attr) {
699 	case hwmon_in_input:
700 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
701 
702 	case hwmon_in_lcrit:
703 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
704 		sfp_hwmon_calibrate_vcc(sfp, value);
705 		return 0;
706 
707 	case hwmon_in_min:
708 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
709 		sfp_hwmon_calibrate_vcc(sfp, value);
710 		return 0;
711 
712 	case hwmon_in_max:
713 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
714 		sfp_hwmon_calibrate_vcc(sfp, value);
715 		return 0;
716 
717 	case hwmon_in_crit:
718 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
719 		sfp_hwmon_calibrate_vcc(sfp, value);
720 		return 0;
721 
722 	case hwmon_in_lcrit_alarm:
723 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
724 		if (err < 0)
725 			return err;
726 
727 		*value = !!(status & SFP_ALARM0_VCC_LOW);
728 		return 0;
729 
730 	case hwmon_in_min_alarm:
731 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
732 		if (err < 0)
733 			return err;
734 
735 		*value = !!(status & SFP_WARN0_VCC_LOW);
736 		return 0;
737 
738 	case hwmon_in_max_alarm:
739 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
740 		if (err < 0)
741 			return err;
742 
743 		*value = !!(status & SFP_WARN0_VCC_HIGH);
744 		return 0;
745 
746 	case hwmon_in_crit_alarm:
747 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
748 		if (err < 0)
749 			return err;
750 
751 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
752 		return 0;
753 	default:
754 		return -EOPNOTSUPP;
755 	}
756 
757 	return -EOPNOTSUPP;
758 }
759 
760 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
761 {
762 	u8 status;
763 	int err;
764 
765 	switch (attr) {
766 	case hwmon_curr_input:
767 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
768 
769 	case hwmon_curr_lcrit:
770 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
771 		sfp_hwmon_calibrate_bias(sfp, value);
772 		return 0;
773 
774 	case hwmon_curr_min:
775 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
776 		sfp_hwmon_calibrate_bias(sfp, value);
777 		return 0;
778 
779 	case hwmon_curr_max:
780 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
781 		sfp_hwmon_calibrate_bias(sfp, value);
782 		return 0;
783 
784 	case hwmon_curr_crit:
785 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
786 		sfp_hwmon_calibrate_bias(sfp, value);
787 		return 0;
788 
789 	case hwmon_curr_lcrit_alarm:
790 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
791 		if (err < 0)
792 			return err;
793 
794 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
795 		return 0;
796 
797 	case hwmon_curr_min_alarm:
798 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
799 		if (err < 0)
800 			return err;
801 
802 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
803 		return 0;
804 
805 	case hwmon_curr_max_alarm:
806 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
807 		if (err < 0)
808 			return err;
809 
810 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
811 		return 0;
812 
813 	case hwmon_curr_crit_alarm:
814 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
815 		if (err < 0)
816 			return err;
817 
818 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
819 		return 0;
820 	default:
821 		return -EOPNOTSUPP;
822 	}
823 
824 	return -EOPNOTSUPP;
825 }
826 
827 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
828 {
829 	u8 status;
830 	int err;
831 
832 	switch (attr) {
833 	case hwmon_power_input:
834 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
835 
836 	case hwmon_power_lcrit:
837 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
838 		sfp_hwmon_calibrate_tx_power(sfp, value);
839 		return 0;
840 
841 	case hwmon_power_min:
842 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
843 		sfp_hwmon_calibrate_tx_power(sfp, value);
844 		return 0;
845 
846 	case hwmon_power_max:
847 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
848 		sfp_hwmon_calibrate_tx_power(sfp, value);
849 		return 0;
850 
851 	case hwmon_power_crit:
852 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
853 		sfp_hwmon_calibrate_tx_power(sfp, value);
854 		return 0;
855 
856 	case hwmon_power_lcrit_alarm:
857 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
858 		if (err < 0)
859 			return err;
860 
861 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
862 		return 0;
863 
864 	case hwmon_power_min_alarm:
865 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
866 		if (err < 0)
867 			return err;
868 
869 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
870 		return 0;
871 
872 	case hwmon_power_max_alarm:
873 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
874 		if (err < 0)
875 			return err;
876 
877 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
878 		return 0;
879 
880 	case hwmon_power_crit_alarm:
881 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
882 		if (err < 0)
883 			return err;
884 
885 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
886 		return 0;
887 	default:
888 		return -EOPNOTSUPP;
889 	}
890 
891 	return -EOPNOTSUPP;
892 }
893 
894 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
895 {
896 	u8 status;
897 	int err;
898 
899 	switch (attr) {
900 	case hwmon_power_input:
901 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
902 
903 	case hwmon_power_lcrit:
904 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
905 		sfp_hwmon_to_rx_power(value);
906 		return 0;
907 
908 	case hwmon_power_min:
909 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
910 		sfp_hwmon_to_rx_power(value);
911 		return 0;
912 
913 	case hwmon_power_max:
914 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
915 		sfp_hwmon_to_rx_power(value);
916 		return 0;
917 
918 	case hwmon_power_crit:
919 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
920 		sfp_hwmon_to_rx_power(value);
921 		return 0;
922 
923 	case hwmon_power_lcrit_alarm:
924 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
925 		if (err < 0)
926 			return err;
927 
928 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
929 		return 0;
930 
931 	case hwmon_power_min_alarm:
932 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
933 		if (err < 0)
934 			return err;
935 
936 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
937 		return 0;
938 
939 	case hwmon_power_max_alarm:
940 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
941 		if (err < 0)
942 			return err;
943 
944 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
945 		return 0;
946 
947 	case hwmon_power_crit_alarm:
948 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
949 		if (err < 0)
950 			return err;
951 
952 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
953 		return 0;
954 	default:
955 		return -EOPNOTSUPP;
956 	}
957 
958 	return -EOPNOTSUPP;
959 }
960 
961 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
962 			  u32 attr, int channel, long *value)
963 {
964 	struct sfp *sfp = dev_get_drvdata(dev);
965 
966 	switch (type) {
967 	case hwmon_temp:
968 		return sfp_hwmon_temp(sfp, attr, value);
969 	case hwmon_in:
970 		return sfp_hwmon_vcc(sfp, attr, value);
971 	case hwmon_curr:
972 		return sfp_hwmon_bias(sfp, attr, value);
973 	case hwmon_power:
974 		switch (channel) {
975 		case 0:
976 			return sfp_hwmon_tx_power(sfp, attr, value);
977 		case 1:
978 			return sfp_hwmon_rx_power(sfp, attr, value);
979 		default:
980 			return -EOPNOTSUPP;
981 		}
982 	default:
983 		return -EOPNOTSUPP;
984 	}
985 }
986 
987 static const struct hwmon_ops sfp_hwmon_ops = {
988 	.is_visible = sfp_hwmon_is_visible,
989 	.read = sfp_hwmon_read,
990 };
991 
992 static u32 sfp_hwmon_chip_config[] = {
993 	HWMON_C_REGISTER_TZ,
994 	0,
995 };
996 
997 static const struct hwmon_channel_info sfp_hwmon_chip = {
998 	.type = hwmon_chip,
999 	.config = sfp_hwmon_chip_config,
1000 };
1001 
1002 static u32 sfp_hwmon_temp_config[] = {
1003 	HWMON_T_INPUT |
1004 	HWMON_T_MAX | HWMON_T_MIN |
1005 	HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1006 	HWMON_T_CRIT | HWMON_T_LCRIT |
1007 	HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM,
1008 	0,
1009 };
1010 
1011 static const struct hwmon_channel_info sfp_hwmon_temp_channel_info = {
1012 	.type = hwmon_temp,
1013 	.config = sfp_hwmon_temp_config,
1014 };
1015 
1016 static u32 sfp_hwmon_vcc_config[] = {
1017 	HWMON_I_INPUT |
1018 	HWMON_I_MAX | HWMON_I_MIN |
1019 	HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1020 	HWMON_I_CRIT | HWMON_I_LCRIT |
1021 	HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM,
1022 	0,
1023 };
1024 
1025 static const struct hwmon_channel_info sfp_hwmon_vcc_channel_info = {
1026 	.type = hwmon_in,
1027 	.config = sfp_hwmon_vcc_config,
1028 };
1029 
1030 static u32 sfp_hwmon_bias_config[] = {
1031 	HWMON_C_INPUT |
1032 	HWMON_C_MAX | HWMON_C_MIN |
1033 	HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1034 	HWMON_C_CRIT | HWMON_C_LCRIT |
1035 	HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM,
1036 	0,
1037 };
1038 
1039 static const struct hwmon_channel_info sfp_hwmon_bias_channel_info = {
1040 	.type = hwmon_curr,
1041 	.config = sfp_hwmon_bias_config,
1042 };
1043 
1044 static u32 sfp_hwmon_power_config[] = {
1045 	/* Transmit power */
1046 	HWMON_P_INPUT |
1047 	HWMON_P_MAX | HWMON_P_MIN |
1048 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1049 	HWMON_P_CRIT | HWMON_P_LCRIT |
1050 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM,
1051 	/* Receive power */
1052 	HWMON_P_INPUT |
1053 	HWMON_P_MAX | HWMON_P_MIN |
1054 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1055 	HWMON_P_CRIT | HWMON_P_LCRIT |
1056 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM,
1057 	0,
1058 };
1059 
1060 static const struct hwmon_channel_info sfp_hwmon_power_channel_info = {
1061 	.type = hwmon_power,
1062 	.config = sfp_hwmon_power_config,
1063 };
1064 
1065 static const struct hwmon_channel_info *sfp_hwmon_info[] = {
1066 	&sfp_hwmon_chip,
1067 	&sfp_hwmon_vcc_channel_info,
1068 	&sfp_hwmon_temp_channel_info,
1069 	&sfp_hwmon_bias_channel_info,
1070 	&sfp_hwmon_power_channel_info,
1071 	NULL,
1072 };
1073 
1074 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1075 	.ops = &sfp_hwmon_ops,
1076 	.info = sfp_hwmon_info,
1077 };
1078 
1079 static int sfp_hwmon_insert(struct sfp *sfp)
1080 {
1081 	int err, i;
1082 
1083 	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
1084 		return 0;
1085 
1086 	if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
1087 		return 0;
1088 
1089 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1090 		/* This driver in general does not support address
1091 		 * change.
1092 		 */
1093 		return 0;
1094 
1095 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1096 	if (err < 0)
1097 		return err;
1098 
1099 	sfp->hwmon_name = kstrdup(dev_name(sfp->dev), GFP_KERNEL);
1100 	if (!sfp->hwmon_name)
1101 		return -ENODEV;
1102 
1103 	for (i = 0; sfp->hwmon_name[i]; i++)
1104 		if (hwmon_is_bad_char(sfp->hwmon_name[i]))
1105 			sfp->hwmon_name[i] = '_';
1106 
1107 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1108 							 sfp->hwmon_name, sfp,
1109 							 &sfp_hwmon_chip_info,
1110 							 NULL);
1111 
1112 	return PTR_ERR_OR_ZERO(sfp->hwmon_dev);
1113 }
1114 
1115 static void sfp_hwmon_remove(struct sfp *sfp)
1116 {
1117 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1118 		hwmon_device_unregister(sfp->hwmon_dev);
1119 		sfp->hwmon_dev = NULL;
1120 		kfree(sfp->hwmon_name);
1121 	}
1122 }
1123 #else
1124 static int sfp_hwmon_insert(struct sfp *sfp)
1125 {
1126 	return 0;
1127 }
1128 
1129 static void sfp_hwmon_remove(struct sfp *sfp)
1130 {
1131 }
1132 #endif
1133 
1134 /* Helpers */
1135 static void sfp_module_tx_disable(struct sfp *sfp)
1136 {
1137 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1138 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1139 	sfp->state |= SFP_F_TX_DISABLE;
1140 	sfp_set_state(sfp, sfp->state);
1141 }
1142 
1143 static void sfp_module_tx_enable(struct sfp *sfp)
1144 {
1145 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1146 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1147 	sfp->state &= ~SFP_F_TX_DISABLE;
1148 	sfp_set_state(sfp, sfp->state);
1149 }
1150 
1151 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1152 {
1153 	unsigned int state = sfp->state;
1154 
1155 	if (state & SFP_F_TX_DISABLE)
1156 		return;
1157 
1158 	sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1159 
1160 	udelay(T_RESET_US);
1161 
1162 	sfp_set_state(sfp, state);
1163 }
1164 
1165 /* SFP state machine */
1166 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1167 {
1168 	if (timeout)
1169 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1170 				 timeout);
1171 	else
1172 		cancel_delayed_work(&sfp->timeout);
1173 }
1174 
1175 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1176 			unsigned int timeout)
1177 {
1178 	sfp->sm_state = state;
1179 	sfp_sm_set_timer(sfp, timeout);
1180 }
1181 
1182 static void sfp_sm_ins_next(struct sfp *sfp, unsigned int state,
1183 			    unsigned int timeout)
1184 {
1185 	sfp->sm_mod_state = state;
1186 	sfp_sm_set_timer(sfp, timeout);
1187 }
1188 
1189 static void sfp_sm_phy_detach(struct sfp *sfp)
1190 {
1191 	phy_stop(sfp->mod_phy);
1192 	sfp_remove_phy(sfp->sfp_bus);
1193 	phy_device_remove(sfp->mod_phy);
1194 	phy_device_free(sfp->mod_phy);
1195 	sfp->mod_phy = NULL;
1196 }
1197 
1198 static void sfp_sm_probe_phy(struct sfp *sfp)
1199 {
1200 	struct phy_device *phy;
1201 	int err;
1202 
1203 	msleep(T_PHY_RESET_MS);
1204 
1205 	phy = mdiobus_scan(sfp->i2c_mii, SFP_PHY_ADDR);
1206 	if (phy == ERR_PTR(-ENODEV)) {
1207 		dev_info(sfp->dev, "no PHY detected\n");
1208 		return;
1209 	}
1210 	if (IS_ERR(phy)) {
1211 		dev_err(sfp->dev, "mdiobus scan returned %ld\n", PTR_ERR(phy));
1212 		return;
1213 	}
1214 
1215 	err = sfp_add_phy(sfp->sfp_bus, phy);
1216 	if (err) {
1217 		phy_device_remove(phy);
1218 		phy_device_free(phy);
1219 		dev_err(sfp->dev, "sfp_add_phy failed: %d\n", err);
1220 		return;
1221 	}
1222 
1223 	sfp->mod_phy = phy;
1224 	phy_start(phy);
1225 }
1226 
1227 static void sfp_sm_link_up(struct sfp *sfp)
1228 {
1229 	sfp_link_up(sfp->sfp_bus);
1230 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1231 }
1232 
1233 static void sfp_sm_link_down(struct sfp *sfp)
1234 {
1235 	sfp_link_down(sfp->sfp_bus);
1236 }
1237 
1238 static void sfp_sm_link_check_los(struct sfp *sfp)
1239 {
1240 	unsigned int los = sfp->state & SFP_F_LOS;
1241 
1242 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1243 	 * are set, we assume that no LOS signal is available.
1244 	 */
1245 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED))
1246 		los ^= SFP_F_LOS;
1247 	else if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL)))
1248 		los = 0;
1249 
1250 	if (los)
1251 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1252 	else
1253 		sfp_sm_link_up(sfp);
1254 }
1255 
1256 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1257 {
1258 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1259 		event == SFP_E_LOS_LOW) ||
1260 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1261 		event == SFP_E_LOS_HIGH);
1262 }
1263 
1264 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1265 {
1266 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1267 		event == SFP_E_LOS_HIGH) ||
1268 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1269 		event == SFP_E_LOS_LOW);
1270 }
1271 
1272 static void sfp_sm_fault(struct sfp *sfp, bool warn)
1273 {
1274 	if (sfp->sm_retries && !--sfp->sm_retries) {
1275 		dev_err(sfp->dev,
1276 			"module persistently indicates fault, disabling\n");
1277 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1278 	} else {
1279 		if (warn)
1280 			dev_err(sfp->dev, "module transmit fault indicated\n");
1281 
1282 		sfp_sm_next(sfp, SFP_S_TX_FAULT, T_FAULT_RECOVER);
1283 	}
1284 }
1285 
1286 static void sfp_sm_mod_init(struct sfp *sfp)
1287 {
1288 	sfp_module_tx_enable(sfp);
1289 
1290 	/* Wait t_init before indicating that the link is up, provided the
1291 	 * current state indicates no TX_FAULT.  If TX_FAULT clears before
1292 	 * this time, that's fine too.
1293 	 */
1294 	sfp_sm_next(sfp, SFP_S_INIT, T_INIT_JIFFIES);
1295 	sfp->sm_retries = 5;
1296 
1297 	/* Setting the serdes link mode is guesswork: there's no
1298 	 * field in the EEPROM which indicates what mode should
1299 	 * be used.
1300 	 *
1301 	 * If it's a gigabit-only fiber module, it probably does
1302 	 * not have a PHY, so switch to 802.3z negotiation mode.
1303 	 * Otherwise, switch to SGMII mode (which is required to
1304 	 * support non-gigabit speeds) and probe for a PHY.
1305 	 */
1306 	if (sfp->id.base.e1000_base_t ||
1307 	    sfp->id.base.e100_base_lx ||
1308 	    sfp->id.base.e100_base_fx)
1309 		sfp_sm_probe_phy(sfp);
1310 }
1311 
1312 static int sfp_sm_mod_hpower(struct sfp *sfp)
1313 {
1314 	u32 power;
1315 	u8 val;
1316 	int err;
1317 
1318 	power = 1000;
1319 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1320 		power = 1500;
1321 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1322 		power = 2000;
1323 
1324 	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE &&
1325 	    (sfp->id.ext.diagmon & (SFP_DIAGMON_DDM | SFP_DIAGMON_ADDRMODE)) !=
1326 	    SFP_DIAGMON_DDM) {
1327 		/* The module appears not to implement bus address 0xa2,
1328 		 * or requires an address change sequence, so assume that
1329 		 * the module powers up in the indicated power mode.
1330 		 */
1331 		if (power > sfp->max_power_mW) {
1332 			dev_err(sfp->dev,
1333 				"Host does not support %u.%uW modules\n",
1334 				power / 1000, (power / 100) % 10);
1335 			return -EINVAL;
1336 		}
1337 		return 0;
1338 	}
1339 
1340 	if (power > sfp->max_power_mW) {
1341 		dev_warn(sfp->dev,
1342 			 "Host does not support %u.%uW modules, module left in power mode 1\n",
1343 			 power / 1000, (power / 100) % 10);
1344 		return 0;
1345 	}
1346 
1347 	if (power <= 1000)
1348 		return 0;
1349 
1350 	err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1351 	if (err != sizeof(val)) {
1352 		dev_err(sfp->dev, "Failed to read EEPROM: %d\n", err);
1353 		err = -EAGAIN;
1354 		goto err;
1355 	}
1356 
1357 	val |= BIT(0);
1358 
1359 	err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1360 	if (err != sizeof(val)) {
1361 		dev_err(sfp->dev, "Failed to write EEPROM: %d\n", err);
1362 		err = -EAGAIN;
1363 		goto err;
1364 	}
1365 
1366 	dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1367 		 power / 1000, (power / 100) % 10);
1368 	return T_HPOWER_LEVEL;
1369 
1370 err:
1371 	return err;
1372 }
1373 
1374 static int sfp_sm_mod_probe(struct sfp *sfp)
1375 {
1376 	/* SFP module inserted - read I2C data */
1377 	struct sfp_eeprom_id id;
1378 	bool cotsworks;
1379 	u8 check;
1380 	int ret;
1381 
1382 	ret = sfp_read(sfp, false, 0, &id, sizeof(id));
1383 	if (ret < 0) {
1384 		dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
1385 		return -EAGAIN;
1386 	}
1387 
1388 	if (ret != sizeof(id)) {
1389 		dev_err(sfp->dev, "EEPROM short read: %d\n", ret);
1390 		return -EAGAIN;
1391 	}
1392 
1393 	/* Cotsworks do not seem to update the checksums when they
1394 	 * do the final programming with the final module part number,
1395 	 * serial number and date code.
1396 	 */
1397 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
1398 
1399 	/* Validate the checksum over the base structure */
1400 	check = sfp_check(&id.base, sizeof(id.base) - 1);
1401 	if (check != id.base.cc_base) {
1402 		if (cotsworks) {
1403 			dev_warn(sfp->dev,
1404 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
1405 				 check, id.base.cc_base);
1406 		} else {
1407 			dev_err(sfp->dev,
1408 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
1409 				check, id.base.cc_base);
1410 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1411 				       16, 1, &id, sizeof(id), true);
1412 			return -EINVAL;
1413 		}
1414 	}
1415 
1416 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
1417 	if (check != id.ext.cc_ext) {
1418 		if (cotsworks) {
1419 			dev_warn(sfp->dev,
1420 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
1421 				 check, id.ext.cc_ext);
1422 		} else {
1423 			dev_err(sfp->dev,
1424 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
1425 				check, id.ext.cc_ext);
1426 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1427 				       16, 1, &id, sizeof(id), true);
1428 			memset(&id.ext, 0, sizeof(id.ext));
1429 		}
1430 	}
1431 
1432 	sfp->id = id;
1433 
1434 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
1435 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
1436 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
1437 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
1438 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
1439 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
1440 
1441 	/* Check whether we support this module */
1442 	if (!sfp->type->module_supported(&sfp->id)) {
1443 		dev_err(sfp->dev,
1444 			"module is not supported - phys id 0x%02x 0x%02x\n",
1445 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
1446 		return -EINVAL;
1447 	}
1448 
1449 	/* If the module requires address swap mode, warn about it */
1450 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1451 		dev_warn(sfp->dev,
1452 			 "module address swap to access page 0xA2 is not supported.\n");
1453 
1454 	ret = sfp_hwmon_insert(sfp);
1455 	if (ret < 0)
1456 		return ret;
1457 
1458 	ret = sfp_module_insert(sfp->sfp_bus, &sfp->id);
1459 	if (ret < 0)
1460 		return ret;
1461 
1462 	return sfp_sm_mod_hpower(sfp);
1463 }
1464 
1465 static void sfp_sm_mod_remove(struct sfp *sfp)
1466 {
1467 	sfp_module_remove(sfp->sfp_bus);
1468 
1469 	sfp_hwmon_remove(sfp);
1470 
1471 	if (sfp->mod_phy)
1472 		sfp_sm_phy_detach(sfp);
1473 
1474 	sfp_module_tx_disable(sfp);
1475 
1476 	memset(&sfp->id, 0, sizeof(sfp->id));
1477 
1478 	dev_info(sfp->dev, "module removed\n");
1479 }
1480 
1481 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
1482 {
1483 	mutex_lock(&sfp->sm_mutex);
1484 
1485 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
1486 		mod_state_to_str(sfp->sm_mod_state),
1487 		dev_state_to_str(sfp->sm_dev_state),
1488 		sm_state_to_str(sfp->sm_state),
1489 		event_to_str(event));
1490 
1491 	/* This state machine tracks the insert/remove state of
1492 	 * the module, and handles probing the on-board EEPROM.
1493 	 */
1494 	switch (sfp->sm_mod_state) {
1495 	default:
1496 		if (event == SFP_E_INSERT && sfp->attached) {
1497 			sfp_module_tx_disable(sfp);
1498 			sfp_sm_ins_next(sfp, SFP_MOD_PROBE, T_PROBE_INIT);
1499 		}
1500 		break;
1501 
1502 	case SFP_MOD_PROBE:
1503 		if (event == SFP_E_REMOVE) {
1504 			sfp_sm_ins_next(sfp, SFP_MOD_EMPTY, 0);
1505 		} else if (event == SFP_E_TIMEOUT) {
1506 			int val = sfp_sm_mod_probe(sfp);
1507 
1508 			if (val == 0)
1509 				sfp_sm_ins_next(sfp, SFP_MOD_PRESENT, 0);
1510 			else if (val > 0)
1511 				sfp_sm_ins_next(sfp, SFP_MOD_HPOWER, val);
1512 			else if (val != -EAGAIN)
1513 				sfp_sm_ins_next(sfp, SFP_MOD_ERROR, 0);
1514 			else
1515 				sfp_sm_set_timer(sfp, T_PROBE_RETRY);
1516 		}
1517 		break;
1518 
1519 	case SFP_MOD_HPOWER:
1520 		if (event == SFP_E_TIMEOUT) {
1521 			sfp_sm_ins_next(sfp, SFP_MOD_PRESENT, 0);
1522 			break;
1523 		}
1524 		/* fallthrough */
1525 	case SFP_MOD_PRESENT:
1526 	case SFP_MOD_ERROR:
1527 		if (event == SFP_E_REMOVE) {
1528 			sfp_sm_mod_remove(sfp);
1529 			sfp_sm_ins_next(sfp, SFP_MOD_EMPTY, 0);
1530 		}
1531 		break;
1532 	}
1533 
1534 	/* This state machine tracks the netdev up/down state */
1535 	switch (sfp->sm_dev_state) {
1536 	default:
1537 		if (event == SFP_E_DEV_UP)
1538 			sfp->sm_dev_state = SFP_DEV_UP;
1539 		break;
1540 
1541 	case SFP_DEV_UP:
1542 		if (event == SFP_E_DEV_DOWN) {
1543 			/* If the module has a PHY, avoid raising TX disable
1544 			 * as this resets the PHY. Otherwise, raise it to
1545 			 * turn the laser off.
1546 			 */
1547 			if (!sfp->mod_phy)
1548 				sfp_module_tx_disable(sfp);
1549 			sfp->sm_dev_state = SFP_DEV_DOWN;
1550 		}
1551 		break;
1552 	}
1553 
1554 	/* Some events are global */
1555 	if (sfp->sm_state != SFP_S_DOWN &&
1556 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
1557 	     sfp->sm_dev_state != SFP_DEV_UP)) {
1558 		if (sfp->sm_state == SFP_S_LINK_UP &&
1559 		    sfp->sm_dev_state == SFP_DEV_UP)
1560 			sfp_sm_link_down(sfp);
1561 		if (sfp->mod_phy)
1562 			sfp_sm_phy_detach(sfp);
1563 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
1564 		mutex_unlock(&sfp->sm_mutex);
1565 		return;
1566 	}
1567 
1568 	/* The main state machine */
1569 	switch (sfp->sm_state) {
1570 	case SFP_S_DOWN:
1571 		if (sfp->sm_mod_state == SFP_MOD_PRESENT &&
1572 		    sfp->sm_dev_state == SFP_DEV_UP)
1573 			sfp_sm_mod_init(sfp);
1574 		break;
1575 
1576 	case SFP_S_INIT:
1577 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT)
1578 			sfp_sm_fault(sfp, true);
1579 		else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR)
1580 			sfp_sm_link_check_los(sfp);
1581 		break;
1582 
1583 	case SFP_S_WAIT_LOS:
1584 		if (event == SFP_E_TX_FAULT)
1585 			sfp_sm_fault(sfp, true);
1586 		else if (sfp_los_event_inactive(sfp, event))
1587 			sfp_sm_link_up(sfp);
1588 		break;
1589 
1590 	case SFP_S_LINK_UP:
1591 		if (event == SFP_E_TX_FAULT) {
1592 			sfp_sm_link_down(sfp);
1593 			sfp_sm_fault(sfp, true);
1594 		} else if (sfp_los_event_active(sfp, event)) {
1595 			sfp_sm_link_down(sfp);
1596 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1597 		}
1598 		break;
1599 
1600 	case SFP_S_TX_FAULT:
1601 		if (event == SFP_E_TIMEOUT) {
1602 			sfp_module_tx_fault_reset(sfp);
1603 			sfp_sm_next(sfp, SFP_S_REINIT, T_INIT_JIFFIES);
1604 		}
1605 		break;
1606 
1607 	case SFP_S_REINIT:
1608 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
1609 			sfp_sm_fault(sfp, false);
1610 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
1611 			dev_info(sfp->dev, "module transmit fault recovered\n");
1612 			sfp_sm_link_check_los(sfp);
1613 		}
1614 		break;
1615 
1616 	case SFP_S_TX_DISABLE:
1617 		break;
1618 	}
1619 
1620 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
1621 		mod_state_to_str(sfp->sm_mod_state),
1622 		dev_state_to_str(sfp->sm_dev_state),
1623 		sm_state_to_str(sfp->sm_state));
1624 
1625 	mutex_unlock(&sfp->sm_mutex);
1626 }
1627 
1628 static void sfp_attach(struct sfp *sfp)
1629 {
1630 	sfp->attached = true;
1631 	if (sfp->state & SFP_F_PRESENT)
1632 		sfp_sm_event(sfp, SFP_E_INSERT);
1633 }
1634 
1635 static void sfp_detach(struct sfp *sfp)
1636 {
1637 	sfp->attached = false;
1638 	sfp_sm_event(sfp, SFP_E_REMOVE);
1639 }
1640 
1641 static void sfp_start(struct sfp *sfp)
1642 {
1643 	sfp_sm_event(sfp, SFP_E_DEV_UP);
1644 }
1645 
1646 static void sfp_stop(struct sfp *sfp)
1647 {
1648 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
1649 }
1650 
1651 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
1652 {
1653 	/* locking... and check module is present */
1654 
1655 	if (sfp->id.ext.sff8472_compliance &&
1656 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
1657 		modinfo->type = ETH_MODULE_SFF_8472;
1658 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
1659 	} else {
1660 		modinfo->type = ETH_MODULE_SFF_8079;
1661 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
1662 	}
1663 	return 0;
1664 }
1665 
1666 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
1667 			     u8 *data)
1668 {
1669 	unsigned int first, last, len;
1670 	int ret;
1671 
1672 	if (ee->len == 0)
1673 		return -EINVAL;
1674 
1675 	first = ee->offset;
1676 	last = ee->offset + ee->len;
1677 	if (first < ETH_MODULE_SFF_8079_LEN) {
1678 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
1679 		len -= first;
1680 
1681 		ret = sfp_read(sfp, false, first, data, len);
1682 		if (ret < 0)
1683 			return ret;
1684 
1685 		first += len;
1686 		data += len;
1687 	}
1688 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
1689 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
1690 		len -= first;
1691 		first -= ETH_MODULE_SFF_8079_LEN;
1692 
1693 		ret = sfp_read(sfp, true, first, data, len);
1694 		if (ret < 0)
1695 			return ret;
1696 	}
1697 	return 0;
1698 }
1699 
1700 static const struct sfp_socket_ops sfp_module_ops = {
1701 	.attach = sfp_attach,
1702 	.detach = sfp_detach,
1703 	.start = sfp_start,
1704 	.stop = sfp_stop,
1705 	.module_info = sfp_module_info,
1706 	.module_eeprom = sfp_module_eeprom,
1707 };
1708 
1709 static void sfp_timeout(struct work_struct *work)
1710 {
1711 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
1712 
1713 	rtnl_lock();
1714 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
1715 	rtnl_unlock();
1716 }
1717 
1718 static void sfp_check_state(struct sfp *sfp)
1719 {
1720 	unsigned int state, i, changed;
1721 
1722 	state = sfp_get_state(sfp);
1723 	changed = state ^ sfp->state;
1724 	changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
1725 
1726 	for (i = 0; i < GPIO_MAX; i++)
1727 		if (changed & BIT(i))
1728 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_of_names[i],
1729 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
1730 
1731 	state |= sfp->state & (SFP_F_TX_DISABLE | SFP_F_RATE_SELECT);
1732 	sfp->state = state;
1733 
1734 	rtnl_lock();
1735 	if (changed & SFP_F_PRESENT)
1736 		sfp_sm_event(sfp, state & SFP_F_PRESENT ?
1737 				SFP_E_INSERT : SFP_E_REMOVE);
1738 
1739 	if (changed & SFP_F_TX_FAULT)
1740 		sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
1741 				SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
1742 
1743 	if (changed & SFP_F_LOS)
1744 		sfp_sm_event(sfp, state & SFP_F_LOS ?
1745 				SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
1746 	rtnl_unlock();
1747 }
1748 
1749 static irqreturn_t sfp_irq(int irq, void *data)
1750 {
1751 	struct sfp *sfp = data;
1752 
1753 	sfp_check_state(sfp);
1754 
1755 	return IRQ_HANDLED;
1756 }
1757 
1758 static void sfp_poll(struct work_struct *work)
1759 {
1760 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
1761 
1762 	sfp_check_state(sfp);
1763 	mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
1764 }
1765 
1766 static struct sfp *sfp_alloc(struct device *dev)
1767 {
1768 	struct sfp *sfp;
1769 
1770 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
1771 	if (!sfp)
1772 		return ERR_PTR(-ENOMEM);
1773 
1774 	sfp->dev = dev;
1775 
1776 	mutex_init(&sfp->sm_mutex);
1777 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
1778 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
1779 
1780 	return sfp;
1781 }
1782 
1783 static void sfp_cleanup(void *data)
1784 {
1785 	struct sfp *sfp = data;
1786 
1787 	cancel_delayed_work_sync(&sfp->poll);
1788 	cancel_delayed_work_sync(&sfp->timeout);
1789 	if (sfp->i2c_mii) {
1790 		mdiobus_unregister(sfp->i2c_mii);
1791 		mdiobus_free(sfp->i2c_mii);
1792 	}
1793 	if (sfp->i2c)
1794 		i2c_put_adapter(sfp->i2c);
1795 	kfree(sfp);
1796 }
1797 
1798 static int sfp_probe(struct platform_device *pdev)
1799 {
1800 	const struct sff_data *sff;
1801 	struct sfp *sfp;
1802 	bool poll = false;
1803 	int irq, err, i;
1804 
1805 	sfp = sfp_alloc(&pdev->dev);
1806 	if (IS_ERR(sfp))
1807 		return PTR_ERR(sfp);
1808 
1809 	platform_set_drvdata(pdev, sfp);
1810 
1811 	err = devm_add_action(sfp->dev, sfp_cleanup, sfp);
1812 	if (err < 0)
1813 		return err;
1814 
1815 	sff = sfp->type = &sfp_data;
1816 
1817 	if (pdev->dev.of_node) {
1818 		struct device_node *node = pdev->dev.of_node;
1819 		const struct of_device_id *id;
1820 		struct i2c_adapter *i2c;
1821 		struct device_node *np;
1822 
1823 		id = of_match_node(sfp_of_match, node);
1824 		if (WARN_ON(!id))
1825 			return -EINVAL;
1826 
1827 		sff = sfp->type = id->data;
1828 
1829 		np = of_parse_phandle(node, "i2c-bus", 0);
1830 		if (!np) {
1831 			dev_err(sfp->dev, "missing 'i2c-bus' property\n");
1832 			return -ENODEV;
1833 		}
1834 
1835 		i2c = of_find_i2c_adapter_by_node(np);
1836 		of_node_put(np);
1837 		if (!i2c)
1838 			return -EPROBE_DEFER;
1839 
1840 		err = sfp_i2c_configure(sfp, i2c);
1841 		if (err < 0) {
1842 			i2c_put_adapter(i2c);
1843 			return err;
1844 		}
1845 	}
1846 
1847 	for (i = 0; i < GPIO_MAX; i++)
1848 		if (sff->gpios & BIT(i)) {
1849 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
1850 					   gpio_of_names[i], gpio_flags[i]);
1851 			if (IS_ERR(sfp->gpio[i]))
1852 				return PTR_ERR(sfp->gpio[i]);
1853 		}
1854 
1855 	sfp->get_state = sfp_gpio_get_state;
1856 	sfp->set_state = sfp_gpio_set_state;
1857 
1858 	/* Modules that have no detect signal are always present */
1859 	if (!(sfp->gpio[GPIO_MODDEF0]))
1860 		sfp->get_state = sff_gpio_get_state;
1861 
1862 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
1863 				 &sfp->max_power_mW);
1864 	if (!sfp->max_power_mW)
1865 		sfp->max_power_mW = 1000;
1866 
1867 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
1868 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
1869 
1870 	/* Get the initial state, and always signal TX disable,
1871 	 * since the network interface will not be up.
1872 	 */
1873 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
1874 
1875 	if (sfp->gpio[GPIO_RATE_SELECT] &&
1876 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RATE_SELECT]))
1877 		sfp->state |= SFP_F_RATE_SELECT;
1878 	sfp_set_state(sfp, sfp->state);
1879 	sfp_module_tx_disable(sfp);
1880 
1881 	for (i = 0; i < GPIO_MAX; i++) {
1882 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
1883 			continue;
1884 
1885 		irq = gpiod_to_irq(sfp->gpio[i]);
1886 		if (!irq) {
1887 			poll = true;
1888 			continue;
1889 		}
1890 
1891 		err = devm_request_threaded_irq(sfp->dev, irq, NULL, sfp_irq,
1892 						IRQF_ONESHOT |
1893 						IRQF_TRIGGER_RISING |
1894 						IRQF_TRIGGER_FALLING,
1895 						dev_name(sfp->dev), sfp);
1896 		if (err)
1897 			poll = true;
1898 	}
1899 
1900 	if (poll)
1901 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
1902 
1903 	/* We could have an issue in cases no Tx disable pin is available or
1904 	 * wired as modules using a laser as their light source will continue to
1905 	 * be active when the fiber is removed. This could be a safety issue and
1906 	 * we should at least warn the user about that.
1907 	 */
1908 	if (!sfp->gpio[GPIO_TX_DISABLE])
1909 		dev_warn(sfp->dev,
1910 			 "No tx_disable pin: SFP modules will always be emitting.\n");
1911 
1912 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
1913 	if (!sfp->sfp_bus)
1914 		return -ENOMEM;
1915 
1916 	return 0;
1917 }
1918 
1919 static int sfp_remove(struct platform_device *pdev)
1920 {
1921 	struct sfp *sfp = platform_get_drvdata(pdev);
1922 
1923 	sfp_unregister_socket(sfp->sfp_bus);
1924 
1925 	return 0;
1926 }
1927 
1928 static struct platform_driver sfp_driver = {
1929 	.probe = sfp_probe,
1930 	.remove = sfp_remove,
1931 	.driver = {
1932 		.name = "sfp",
1933 		.of_match_table = sfp_of_match,
1934 	},
1935 };
1936 
1937 static int sfp_init(void)
1938 {
1939 	poll_jiffies = msecs_to_jiffies(100);
1940 
1941 	return platform_driver_register(&sfp_driver);
1942 }
1943 module_init(sfp_init);
1944 
1945 static void sfp_exit(void)
1946 {
1947 	platform_driver_unregister(&sfp_driver);
1948 }
1949 module_exit(sfp_exit);
1950 
1951 MODULE_ALIAS("platform:sfp");
1952 MODULE_AUTHOR("Russell King");
1953 MODULE_LICENSE("GPL v2");
1954