xref: /openbmc/linux/drivers/net/phy/sfp.c (revision 1d1997db)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/acpi.h>
3 #include <linux/ctype.h>
4 #include <linux/delay.h>
5 #include <linux/gpio/consumer.h>
6 #include <linux/hwmon.h>
7 #include <linux/i2c.h>
8 #include <linux/interrupt.h>
9 #include <linux/jiffies.h>
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/of.h>
13 #include <linux/phy.h>
14 #include <linux/platform_device.h>
15 #include <linux/rtnetlink.h>
16 #include <linux/slab.h>
17 #include <linux/workqueue.h>
18 
19 #include "mdio-i2c.h"
20 #include "sfp.h"
21 #include "swphy.h"
22 
23 enum {
24 	GPIO_MODDEF0,
25 	GPIO_LOS,
26 	GPIO_TX_FAULT,
27 	GPIO_TX_DISABLE,
28 	GPIO_RATE_SELECT,
29 	GPIO_MAX,
30 
31 	SFP_F_PRESENT = BIT(GPIO_MODDEF0),
32 	SFP_F_LOS = BIT(GPIO_LOS),
33 	SFP_F_TX_FAULT = BIT(GPIO_TX_FAULT),
34 	SFP_F_TX_DISABLE = BIT(GPIO_TX_DISABLE),
35 	SFP_F_RATE_SELECT = BIT(GPIO_RATE_SELECT),
36 
37 	SFP_E_INSERT = 0,
38 	SFP_E_REMOVE,
39 	SFP_E_DEV_ATTACH,
40 	SFP_E_DEV_DETACH,
41 	SFP_E_DEV_DOWN,
42 	SFP_E_DEV_UP,
43 	SFP_E_TX_FAULT,
44 	SFP_E_TX_CLEAR,
45 	SFP_E_LOS_HIGH,
46 	SFP_E_LOS_LOW,
47 	SFP_E_TIMEOUT,
48 
49 	SFP_MOD_EMPTY = 0,
50 	SFP_MOD_ERROR,
51 	SFP_MOD_PROBE,
52 	SFP_MOD_WAITDEV,
53 	SFP_MOD_HPOWER,
54 	SFP_MOD_WAITPWR,
55 	SFP_MOD_PRESENT,
56 
57 	SFP_DEV_DETACHED = 0,
58 	SFP_DEV_DOWN,
59 	SFP_DEV_UP,
60 
61 	SFP_S_DOWN = 0,
62 	SFP_S_FAIL,
63 	SFP_S_WAIT,
64 	SFP_S_INIT,
65 	SFP_S_INIT_PHY,
66 	SFP_S_INIT_TX_FAULT,
67 	SFP_S_WAIT_LOS,
68 	SFP_S_LINK_UP,
69 	SFP_S_TX_FAULT,
70 	SFP_S_REINIT,
71 	SFP_S_TX_DISABLE,
72 };
73 
74 static const char  * const mod_state_strings[] = {
75 	[SFP_MOD_EMPTY] = "empty",
76 	[SFP_MOD_ERROR] = "error",
77 	[SFP_MOD_PROBE] = "probe",
78 	[SFP_MOD_WAITDEV] = "waitdev",
79 	[SFP_MOD_HPOWER] = "hpower",
80 	[SFP_MOD_WAITPWR] = "waitpwr",
81 	[SFP_MOD_PRESENT] = "present",
82 };
83 
84 static const char *mod_state_to_str(unsigned short mod_state)
85 {
86 	if (mod_state >= ARRAY_SIZE(mod_state_strings))
87 		return "Unknown module state";
88 	return mod_state_strings[mod_state];
89 }
90 
91 static const char * const dev_state_strings[] = {
92 	[SFP_DEV_DETACHED] = "detached",
93 	[SFP_DEV_DOWN] = "down",
94 	[SFP_DEV_UP] = "up",
95 };
96 
97 static const char *dev_state_to_str(unsigned short dev_state)
98 {
99 	if (dev_state >= ARRAY_SIZE(dev_state_strings))
100 		return "Unknown device state";
101 	return dev_state_strings[dev_state];
102 }
103 
104 static const char * const event_strings[] = {
105 	[SFP_E_INSERT] = "insert",
106 	[SFP_E_REMOVE] = "remove",
107 	[SFP_E_DEV_ATTACH] = "dev_attach",
108 	[SFP_E_DEV_DETACH] = "dev_detach",
109 	[SFP_E_DEV_DOWN] = "dev_down",
110 	[SFP_E_DEV_UP] = "dev_up",
111 	[SFP_E_TX_FAULT] = "tx_fault",
112 	[SFP_E_TX_CLEAR] = "tx_clear",
113 	[SFP_E_LOS_HIGH] = "los_high",
114 	[SFP_E_LOS_LOW] = "los_low",
115 	[SFP_E_TIMEOUT] = "timeout",
116 };
117 
118 static const char *event_to_str(unsigned short event)
119 {
120 	if (event >= ARRAY_SIZE(event_strings))
121 		return "Unknown event";
122 	return event_strings[event];
123 }
124 
125 static const char * const sm_state_strings[] = {
126 	[SFP_S_DOWN] = "down",
127 	[SFP_S_FAIL] = "fail",
128 	[SFP_S_WAIT] = "wait",
129 	[SFP_S_INIT] = "init",
130 	[SFP_S_INIT_PHY] = "init_phy",
131 	[SFP_S_INIT_TX_FAULT] = "init_tx_fault",
132 	[SFP_S_WAIT_LOS] = "wait_los",
133 	[SFP_S_LINK_UP] = "link_up",
134 	[SFP_S_TX_FAULT] = "tx_fault",
135 	[SFP_S_REINIT] = "reinit",
136 	[SFP_S_TX_DISABLE] = "rx_disable",
137 };
138 
139 static const char *sm_state_to_str(unsigned short sm_state)
140 {
141 	if (sm_state >= ARRAY_SIZE(sm_state_strings))
142 		return "Unknown state";
143 	return sm_state_strings[sm_state];
144 }
145 
146 static const char *gpio_of_names[] = {
147 	"mod-def0",
148 	"los",
149 	"tx-fault",
150 	"tx-disable",
151 	"rate-select0",
152 };
153 
154 static const enum gpiod_flags gpio_flags[] = {
155 	GPIOD_IN,
156 	GPIOD_IN,
157 	GPIOD_IN,
158 	GPIOD_ASIS,
159 	GPIOD_ASIS,
160 };
161 
162 /* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
163  * non-cooled module to initialise its laser safety circuitry. We wait
164  * an initial T_WAIT period before we check the tx fault to give any PHY
165  * on board (for a copper SFP) time to initialise.
166  */
167 #define T_WAIT			msecs_to_jiffies(50)
168 #define T_START_UP		msecs_to_jiffies(300)
169 #define T_START_UP_BAD_GPON	msecs_to_jiffies(60000)
170 
171 /* t_reset is the time required to assert the TX_DISABLE signal to reset
172  * an indicated TX_FAULT.
173  */
174 #define T_RESET_US		10
175 #define T_FAULT_RECOVER		msecs_to_jiffies(1000)
176 
177 /* N_FAULT_INIT is the number of recovery attempts at module initialisation
178  * time. If the TX_FAULT signal is not deasserted after this number of
179  * attempts at clearing it, we decide that the module is faulty.
180  * N_FAULT is the same but after the module has initialised.
181  */
182 #define N_FAULT_INIT		5
183 #define N_FAULT			5
184 
185 /* T_PHY_RETRY is the time interval between attempts to probe the PHY.
186  * R_PHY_RETRY is the number of attempts.
187  */
188 #define T_PHY_RETRY		msecs_to_jiffies(50)
189 #define R_PHY_RETRY		12
190 
191 /* SFP module presence detection is poor: the three MOD DEF signals are
192  * the same length on the PCB, which means it's possible for MOD DEF 0 to
193  * connect before the I2C bus on MOD DEF 1/2.
194  *
195  * The SFF-8472 specifies t_serial ("Time from power on until module is
196  * ready for data transmission over the two wire serial bus.") as 300ms.
197  */
198 #define T_SERIAL		msecs_to_jiffies(300)
199 #define T_HPOWER_LEVEL		msecs_to_jiffies(300)
200 #define T_PROBE_RETRY_INIT	msecs_to_jiffies(100)
201 #define R_PROBE_RETRY_INIT	10
202 #define T_PROBE_RETRY_SLOW	msecs_to_jiffies(5000)
203 #define R_PROBE_RETRY_SLOW	12
204 
205 /* SFP modules appear to always have their PHY configured for bus address
206  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
207  */
208 #define SFP_PHY_ADDR	22
209 
210 struct sff_data {
211 	unsigned int gpios;
212 	bool (*module_supported)(const struct sfp_eeprom_id *id);
213 };
214 
215 struct sfp {
216 	struct device *dev;
217 	struct i2c_adapter *i2c;
218 	struct mii_bus *i2c_mii;
219 	struct sfp_bus *sfp_bus;
220 	struct phy_device *mod_phy;
221 	const struct sff_data *type;
222 	u32 max_power_mW;
223 
224 	unsigned int (*get_state)(struct sfp *);
225 	void (*set_state)(struct sfp *, unsigned int);
226 	int (*read)(struct sfp *, bool, u8, void *, size_t);
227 	int (*write)(struct sfp *, bool, u8, void *, size_t);
228 
229 	struct gpio_desc *gpio[GPIO_MAX];
230 	int gpio_irq[GPIO_MAX];
231 
232 	bool need_poll;
233 
234 	struct mutex st_mutex;			/* Protects state */
235 	unsigned int state_soft_mask;
236 	unsigned int state;
237 	struct delayed_work poll;
238 	struct delayed_work timeout;
239 	struct mutex sm_mutex;			/* Protects state machine */
240 	unsigned char sm_mod_state;
241 	unsigned char sm_mod_tries_init;
242 	unsigned char sm_mod_tries;
243 	unsigned char sm_dev_state;
244 	unsigned short sm_state;
245 	unsigned char sm_fault_retries;
246 	unsigned char sm_phy_retries;
247 
248 	struct sfp_eeprom_id id;
249 	unsigned int module_power_mW;
250 	unsigned int module_t_start_up;
251 
252 #if IS_ENABLED(CONFIG_HWMON)
253 	struct sfp_diag diag;
254 	struct delayed_work hwmon_probe;
255 	unsigned int hwmon_tries;
256 	struct device *hwmon_dev;
257 	char *hwmon_name;
258 #endif
259 
260 };
261 
262 static bool sff_module_supported(const struct sfp_eeprom_id *id)
263 {
264 	return id->base.phys_id == SFF8024_ID_SFF_8472 &&
265 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
266 }
267 
268 static const struct sff_data sff_data = {
269 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
270 	.module_supported = sff_module_supported,
271 };
272 
273 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
274 {
275 	return id->base.phys_id == SFF8024_ID_SFP &&
276 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
277 }
278 
279 static const struct sff_data sfp_data = {
280 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
281 		 SFP_F_TX_DISABLE | SFP_F_RATE_SELECT,
282 	.module_supported = sfp_module_supported,
283 };
284 
285 static const struct of_device_id sfp_of_match[] = {
286 	{ .compatible = "sff,sff", .data = &sff_data, },
287 	{ .compatible = "sff,sfp", .data = &sfp_data, },
288 	{ },
289 };
290 MODULE_DEVICE_TABLE(of, sfp_of_match);
291 
292 static unsigned long poll_jiffies;
293 
294 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
295 {
296 	unsigned int i, state, v;
297 
298 	for (i = state = 0; i < GPIO_MAX; i++) {
299 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
300 			continue;
301 
302 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
303 		if (v)
304 			state |= BIT(i);
305 	}
306 
307 	return state;
308 }
309 
310 static unsigned int sff_gpio_get_state(struct sfp *sfp)
311 {
312 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
313 }
314 
315 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
316 {
317 	if (state & SFP_F_PRESENT) {
318 		/* If the module is present, drive the signals */
319 		if (sfp->gpio[GPIO_TX_DISABLE])
320 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
321 					       state & SFP_F_TX_DISABLE);
322 		if (state & SFP_F_RATE_SELECT)
323 			gpiod_direction_output(sfp->gpio[GPIO_RATE_SELECT],
324 					       state & SFP_F_RATE_SELECT);
325 	} else {
326 		/* Otherwise, let them float to the pull-ups */
327 		if (sfp->gpio[GPIO_TX_DISABLE])
328 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
329 		if (state & SFP_F_RATE_SELECT)
330 			gpiod_direction_input(sfp->gpio[GPIO_RATE_SELECT]);
331 	}
332 }
333 
334 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
335 			size_t len)
336 {
337 	struct i2c_msg msgs[2];
338 	u8 bus_addr = a2 ? 0x51 : 0x50;
339 	size_t this_len;
340 	int ret;
341 
342 	msgs[0].addr = bus_addr;
343 	msgs[0].flags = 0;
344 	msgs[0].len = 1;
345 	msgs[0].buf = &dev_addr;
346 	msgs[1].addr = bus_addr;
347 	msgs[1].flags = I2C_M_RD;
348 	msgs[1].len = len;
349 	msgs[1].buf = buf;
350 
351 	while (len) {
352 		this_len = len;
353 		if (this_len > 16)
354 			this_len = 16;
355 
356 		msgs[1].len = this_len;
357 
358 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
359 		if (ret < 0)
360 			return ret;
361 
362 		if (ret != ARRAY_SIZE(msgs))
363 			break;
364 
365 		msgs[1].buf += this_len;
366 		dev_addr += this_len;
367 		len -= this_len;
368 	}
369 
370 	return msgs[1].buf - (u8 *)buf;
371 }
372 
373 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
374 	size_t len)
375 {
376 	struct i2c_msg msgs[1];
377 	u8 bus_addr = a2 ? 0x51 : 0x50;
378 	int ret;
379 
380 	msgs[0].addr = bus_addr;
381 	msgs[0].flags = 0;
382 	msgs[0].len = 1 + len;
383 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
384 	if (!msgs[0].buf)
385 		return -ENOMEM;
386 
387 	msgs[0].buf[0] = dev_addr;
388 	memcpy(&msgs[0].buf[1], buf, len);
389 
390 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
391 
392 	kfree(msgs[0].buf);
393 
394 	if (ret < 0)
395 		return ret;
396 
397 	return ret == ARRAY_SIZE(msgs) ? len : 0;
398 }
399 
400 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
401 {
402 	struct mii_bus *i2c_mii;
403 	int ret;
404 
405 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
406 		return -EINVAL;
407 
408 	sfp->i2c = i2c;
409 	sfp->read = sfp_i2c_read;
410 	sfp->write = sfp_i2c_write;
411 
412 	i2c_mii = mdio_i2c_alloc(sfp->dev, i2c);
413 	if (IS_ERR(i2c_mii))
414 		return PTR_ERR(i2c_mii);
415 
416 	i2c_mii->name = "SFP I2C Bus";
417 	i2c_mii->phy_mask = ~0;
418 
419 	ret = mdiobus_register(i2c_mii);
420 	if (ret < 0) {
421 		mdiobus_free(i2c_mii);
422 		return ret;
423 	}
424 
425 	sfp->i2c_mii = i2c_mii;
426 
427 	return 0;
428 }
429 
430 /* Interface */
431 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
432 {
433 	return sfp->read(sfp, a2, addr, buf, len);
434 }
435 
436 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
437 {
438 	return sfp->write(sfp, a2, addr, buf, len);
439 }
440 
441 static unsigned int sfp_soft_get_state(struct sfp *sfp)
442 {
443 	unsigned int state = 0;
444 	u8 status;
445 
446 	if (sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status)) ==
447 		     sizeof(status)) {
448 		if (status & SFP_STATUS_RX_LOS)
449 			state |= SFP_F_LOS;
450 		if (status & SFP_STATUS_TX_FAULT)
451 			state |= SFP_F_TX_FAULT;
452 	}
453 
454 	return state & sfp->state_soft_mask;
455 }
456 
457 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state)
458 {
459 	u8 status;
460 
461 	if (sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status)) ==
462 		     sizeof(status)) {
463 		if (state & SFP_F_TX_DISABLE)
464 			status |= SFP_STATUS_TX_DISABLE_FORCE;
465 		else
466 			status &= ~SFP_STATUS_TX_DISABLE_FORCE;
467 
468 		sfp_write(sfp, true, SFP_STATUS, &status, sizeof(status));
469 	}
470 }
471 
472 static void sfp_soft_start_poll(struct sfp *sfp)
473 {
474 	const struct sfp_eeprom_id *id = &sfp->id;
475 
476 	sfp->state_soft_mask = 0;
477 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE &&
478 	    !sfp->gpio[GPIO_TX_DISABLE])
479 		sfp->state_soft_mask |= SFP_F_TX_DISABLE;
480 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT &&
481 	    !sfp->gpio[GPIO_TX_FAULT])
482 		sfp->state_soft_mask |= SFP_F_TX_FAULT;
483 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS &&
484 	    !sfp->gpio[GPIO_LOS])
485 		sfp->state_soft_mask |= SFP_F_LOS;
486 
487 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
488 	    !sfp->need_poll)
489 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
490 }
491 
492 static void sfp_soft_stop_poll(struct sfp *sfp)
493 {
494 	sfp->state_soft_mask = 0;
495 }
496 
497 static unsigned int sfp_get_state(struct sfp *sfp)
498 {
499 	unsigned int state = sfp->get_state(sfp);
500 
501 	if (state & SFP_F_PRESENT &&
502 	    sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT))
503 		state |= sfp_soft_get_state(sfp);
504 
505 	return state;
506 }
507 
508 static void sfp_set_state(struct sfp *sfp, unsigned int state)
509 {
510 	sfp->set_state(sfp, state);
511 
512 	if (state & SFP_F_PRESENT &&
513 	    sfp->state_soft_mask & SFP_F_TX_DISABLE)
514 		sfp_soft_set_state(sfp, state);
515 }
516 
517 static unsigned int sfp_check(void *buf, size_t len)
518 {
519 	u8 *p, check;
520 
521 	for (p = buf, check = 0; len; p++, len--)
522 		check += *p;
523 
524 	return check;
525 }
526 
527 /* hwmon */
528 #if IS_ENABLED(CONFIG_HWMON)
529 static umode_t sfp_hwmon_is_visible(const void *data,
530 				    enum hwmon_sensor_types type,
531 				    u32 attr, int channel)
532 {
533 	const struct sfp *sfp = data;
534 
535 	switch (type) {
536 	case hwmon_temp:
537 		switch (attr) {
538 		case hwmon_temp_min_alarm:
539 		case hwmon_temp_max_alarm:
540 		case hwmon_temp_lcrit_alarm:
541 		case hwmon_temp_crit_alarm:
542 		case hwmon_temp_min:
543 		case hwmon_temp_max:
544 		case hwmon_temp_lcrit:
545 		case hwmon_temp_crit:
546 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
547 				return 0;
548 			/* fall through */
549 		case hwmon_temp_input:
550 		case hwmon_temp_label:
551 			return 0444;
552 		default:
553 			return 0;
554 		}
555 	case hwmon_in:
556 		switch (attr) {
557 		case hwmon_in_min_alarm:
558 		case hwmon_in_max_alarm:
559 		case hwmon_in_lcrit_alarm:
560 		case hwmon_in_crit_alarm:
561 		case hwmon_in_min:
562 		case hwmon_in_max:
563 		case hwmon_in_lcrit:
564 		case hwmon_in_crit:
565 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
566 				return 0;
567 			/* fall through */
568 		case hwmon_in_input:
569 		case hwmon_in_label:
570 			return 0444;
571 		default:
572 			return 0;
573 		}
574 	case hwmon_curr:
575 		switch (attr) {
576 		case hwmon_curr_min_alarm:
577 		case hwmon_curr_max_alarm:
578 		case hwmon_curr_lcrit_alarm:
579 		case hwmon_curr_crit_alarm:
580 		case hwmon_curr_min:
581 		case hwmon_curr_max:
582 		case hwmon_curr_lcrit:
583 		case hwmon_curr_crit:
584 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
585 				return 0;
586 			/* fall through */
587 		case hwmon_curr_input:
588 		case hwmon_curr_label:
589 			return 0444;
590 		default:
591 			return 0;
592 		}
593 	case hwmon_power:
594 		/* External calibration of receive power requires
595 		 * floating point arithmetic. Doing that in the kernel
596 		 * is not easy, so just skip it. If the module does
597 		 * not require external calibration, we can however
598 		 * show receiver power, since FP is then not needed.
599 		 */
600 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
601 		    channel == 1)
602 			return 0;
603 		switch (attr) {
604 		case hwmon_power_min_alarm:
605 		case hwmon_power_max_alarm:
606 		case hwmon_power_lcrit_alarm:
607 		case hwmon_power_crit_alarm:
608 		case hwmon_power_min:
609 		case hwmon_power_max:
610 		case hwmon_power_lcrit:
611 		case hwmon_power_crit:
612 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
613 				return 0;
614 			/* fall through */
615 		case hwmon_power_input:
616 		case hwmon_power_label:
617 			return 0444;
618 		default:
619 			return 0;
620 		}
621 	default:
622 		return 0;
623 	}
624 }
625 
626 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
627 {
628 	__be16 val;
629 	int err;
630 
631 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
632 	if (err < 0)
633 		return err;
634 
635 	*value = be16_to_cpu(val);
636 
637 	return 0;
638 }
639 
640 static void sfp_hwmon_to_rx_power(long *value)
641 {
642 	*value = DIV_ROUND_CLOSEST(*value, 10);
643 }
644 
645 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
646 				long *value)
647 {
648 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
649 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
650 }
651 
652 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
653 {
654 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
655 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
656 
657 	if (*value >= 0x8000)
658 		*value -= 0x10000;
659 
660 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
661 }
662 
663 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
664 {
665 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
666 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
667 
668 	*value = DIV_ROUND_CLOSEST(*value, 10);
669 }
670 
671 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
672 {
673 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
674 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
675 
676 	*value = DIV_ROUND_CLOSEST(*value, 500);
677 }
678 
679 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
680 {
681 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
682 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
683 
684 	*value = DIV_ROUND_CLOSEST(*value, 10);
685 }
686 
687 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
688 {
689 	int err;
690 
691 	err = sfp_hwmon_read_sensor(sfp, reg, value);
692 	if (err < 0)
693 		return err;
694 
695 	sfp_hwmon_calibrate_temp(sfp, value);
696 
697 	return 0;
698 }
699 
700 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
701 {
702 	int err;
703 
704 	err = sfp_hwmon_read_sensor(sfp, reg, value);
705 	if (err < 0)
706 		return err;
707 
708 	sfp_hwmon_calibrate_vcc(sfp, value);
709 
710 	return 0;
711 }
712 
713 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
714 {
715 	int err;
716 
717 	err = sfp_hwmon_read_sensor(sfp, reg, value);
718 	if (err < 0)
719 		return err;
720 
721 	sfp_hwmon_calibrate_bias(sfp, value);
722 
723 	return 0;
724 }
725 
726 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
727 {
728 	int err;
729 
730 	err = sfp_hwmon_read_sensor(sfp, reg, value);
731 	if (err < 0)
732 		return err;
733 
734 	sfp_hwmon_calibrate_tx_power(sfp, value);
735 
736 	return 0;
737 }
738 
739 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
740 {
741 	int err;
742 
743 	err = sfp_hwmon_read_sensor(sfp, reg, value);
744 	if (err < 0)
745 		return err;
746 
747 	sfp_hwmon_to_rx_power(value);
748 
749 	return 0;
750 }
751 
752 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
753 {
754 	u8 status;
755 	int err;
756 
757 	switch (attr) {
758 	case hwmon_temp_input:
759 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
760 
761 	case hwmon_temp_lcrit:
762 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
763 		sfp_hwmon_calibrate_temp(sfp, value);
764 		return 0;
765 
766 	case hwmon_temp_min:
767 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
768 		sfp_hwmon_calibrate_temp(sfp, value);
769 		return 0;
770 	case hwmon_temp_max:
771 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
772 		sfp_hwmon_calibrate_temp(sfp, value);
773 		return 0;
774 
775 	case hwmon_temp_crit:
776 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
777 		sfp_hwmon_calibrate_temp(sfp, value);
778 		return 0;
779 
780 	case hwmon_temp_lcrit_alarm:
781 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
782 		if (err < 0)
783 			return err;
784 
785 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
786 		return 0;
787 
788 	case hwmon_temp_min_alarm:
789 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
790 		if (err < 0)
791 			return err;
792 
793 		*value = !!(status & SFP_WARN0_TEMP_LOW);
794 		return 0;
795 
796 	case hwmon_temp_max_alarm:
797 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
798 		if (err < 0)
799 			return err;
800 
801 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
802 		return 0;
803 
804 	case hwmon_temp_crit_alarm:
805 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
806 		if (err < 0)
807 			return err;
808 
809 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
810 		return 0;
811 	default:
812 		return -EOPNOTSUPP;
813 	}
814 
815 	return -EOPNOTSUPP;
816 }
817 
818 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
819 {
820 	u8 status;
821 	int err;
822 
823 	switch (attr) {
824 	case hwmon_in_input:
825 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
826 
827 	case hwmon_in_lcrit:
828 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
829 		sfp_hwmon_calibrate_vcc(sfp, value);
830 		return 0;
831 
832 	case hwmon_in_min:
833 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
834 		sfp_hwmon_calibrate_vcc(sfp, value);
835 		return 0;
836 
837 	case hwmon_in_max:
838 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
839 		sfp_hwmon_calibrate_vcc(sfp, value);
840 		return 0;
841 
842 	case hwmon_in_crit:
843 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
844 		sfp_hwmon_calibrate_vcc(sfp, value);
845 		return 0;
846 
847 	case hwmon_in_lcrit_alarm:
848 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
849 		if (err < 0)
850 			return err;
851 
852 		*value = !!(status & SFP_ALARM0_VCC_LOW);
853 		return 0;
854 
855 	case hwmon_in_min_alarm:
856 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
857 		if (err < 0)
858 			return err;
859 
860 		*value = !!(status & SFP_WARN0_VCC_LOW);
861 		return 0;
862 
863 	case hwmon_in_max_alarm:
864 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
865 		if (err < 0)
866 			return err;
867 
868 		*value = !!(status & SFP_WARN0_VCC_HIGH);
869 		return 0;
870 
871 	case hwmon_in_crit_alarm:
872 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
873 		if (err < 0)
874 			return err;
875 
876 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
877 		return 0;
878 	default:
879 		return -EOPNOTSUPP;
880 	}
881 
882 	return -EOPNOTSUPP;
883 }
884 
885 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
886 {
887 	u8 status;
888 	int err;
889 
890 	switch (attr) {
891 	case hwmon_curr_input:
892 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
893 
894 	case hwmon_curr_lcrit:
895 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
896 		sfp_hwmon_calibrate_bias(sfp, value);
897 		return 0;
898 
899 	case hwmon_curr_min:
900 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
901 		sfp_hwmon_calibrate_bias(sfp, value);
902 		return 0;
903 
904 	case hwmon_curr_max:
905 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
906 		sfp_hwmon_calibrate_bias(sfp, value);
907 		return 0;
908 
909 	case hwmon_curr_crit:
910 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
911 		sfp_hwmon_calibrate_bias(sfp, value);
912 		return 0;
913 
914 	case hwmon_curr_lcrit_alarm:
915 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
916 		if (err < 0)
917 			return err;
918 
919 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
920 		return 0;
921 
922 	case hwmon_curr_min_alarm:
923 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
924 		if (err < 0)
925 			return err;
926 
927 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
928 		return 0;
929 
930 	case hwmon_curr_max_alarm:
931 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
932 		if (err < 0)
933 			return err;
934 
935 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
936 		return 0;
937 
938 	case hwmon_curr_crit_alarm:
939 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
940 		if (err < 0)
941 			return err;
942 
943 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
944 		return 0;
945 	default:
946 		return -EOPNOTSUPP;
947 	}
948 
949 	return -EOPNOTSUPP;
950 }
951 
952 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
953 {
954 	u8 status;
955 	int err;
956 
957 	switch (attr) {
958 	case hwmon_power_input:
959 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
960 
961 	case hwmon_power_lcrit:
962 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
963 		sfp_hwmon_calibrate_tx_power(sfp, value);
964 		return 0;
965 
966 	case hwmon_power_min:
967 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
968 		sfp_hwmon_calibrate_tx_power(sfp, value);
969 		return 0;
970 
971 	case hwmon_power_max:
972 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
973 		sfp_hwmon_calibrate_tx_power(sfp, value);
974 		return 0;
975 
976 	case hwmon_power_crit:
977 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
978 		sfp_hwmon_calibrate_tx_power(sfp, value);
979 		return 0;
980 
981 	case hwmon_power_lcrit_alarm:
982 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
983 		if (err < 0)
984 			return err;
985 
986 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
987 		return 0;
988 
989 	case hwmon_power_min_alarm:
990 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
991 		if (err < 0)
992 			return err;
993 
994 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
995 		return 0;
996 
997 	case hwmon_power_max_alarm:
998 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
999 		if (err < 0)
1000 			return err;
1001 
1002 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1003 		return 0;
1004 
1005 	case hwmon_power_crit_alarm:
1006 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1007 		if (err < 0)
1008 			return err;
1009 
1010 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1011 		return 0;
1012 	default:
1013 		return -EOPNOTSUPP;
1014 	}
1015 
1016 	return -EOPNOTSUPP;
1017 }
1018 
1019 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1020 {
1021 	u8 status;
1022 	int err;
1023 
1024 	switch (attr) {
1025 	case hwmon_power_input:
1026 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1027 
1028 	case hwmon_power_lcrit:
1029 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1030 		sfp_hwmon_to_rx_power(value);
1031 		return 0;
1032 
1033 	case hwmon_power_min:
1034 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1035 		sfp_hwmon_to_rx_power(value);
1036 		return 0;
1037 
1038 	case hwmon_power_max:
1039 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1040 		sfp_hwmon_to_rx_power(value);
1041 		return 0;
1042 
1043 	case hwmon_power_crit:
1044 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1045 		sfp_hwmon_to_rx_power(value);
1046 		return 0;
1047 
1048 	case hwmon_power_lcrit_alarm:
1049 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1050 		if (err < 0)
1051 			return err;
1052 
1053 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1054 		return 0;
1055 
1056 	case hwmon_power_min_alarm:
1057 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1058 		if (err < 0)
1059 			return err;
1060 
1061 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1062 		return 0;
1063 
1064 	case hwmon_power_max_alarm:
1065 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1066 		if (err < 0)
1067 			return err;
1068 
1069 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1070 		return 0;
1071 
1072 	case hwmon_power_crit_alarm:
1073 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1074 		if (err < 0)
1075 			return err;
1076 
1077 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1078 		return 0;
1079 	default:
1080 		return -EOPNOTSUPP;
1081 	}
1082 
1083 	return -EOPNOTSUPP;
1084 }
1085 
1086 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1087 			  u32 attr, int channel, long *value)
1088 {
1089 	struct sfp *sfp = dev_get_drvdata(dev);
1090 
1091 	switch (type) {
1092 	case hwmon_temp:
1093 		return sfp_hwmon_temp(sfp, attr, value);
1094 	case hwmon_in:
1095 		return sfp_hwmon_vcc(sfp, attr, value);
1096 	case hwmon_curr:
1097 		return sfp_hwmon_bias(sfp, attr, value);
1098 	case hwmon_power:
1099 		switch (channel) {
1100 		case 0:
1101 			return sfp_hwmon_tx_power(sfp, attr, value);
1102 		case 1:
1103 			return sfp_hwmon_rx_power(sfp, attr, value);
1104 		default:
1105 			return -EOPNOTSUPP;
1106 		}
1107 	default:
1108 		return -EOPNOTSUPP;
1109 	}
1110 }
1111 
1112 static const char *const sfp_hwmon_power_labels[] = {
1113 	"TX_power",
1114 	"RX_power",
1115 };
1116 
1117 static int sfp_hwmon_read_string(struct device *dev,
1118 				 enum hwmon_sensor_types type,
1119 				 u32 attr, int channel, const char **str)
1120 {
1121 	switch (type) {
1122 	case hwmon_curr:
1123 		switch (attr) {
1124 		case hwmon_curr_label:
1125 			*str = "bias";
1126 			return 0;
1127 		default:
1128 			return -EOPNOTSUPP;
1129 		}
1130 		break;
1131 	case hwmon_temp:
1132 		switch (attr) {
1133 		case hwmon_temp_label:
1134 			*str = "temperature";
1135 			return 0;
1136 		default:
1137 			return -EOPNOTSUPP;
1138 		}
1139 		break;
1140 	case hwmon_in:
1141 		switch (attr) {
1142 		case hwmon_in_label:
1143 			*str = "VCC";
1144 			return 0;
1145 		default:
1146 			return -EOPNOTSUPP;
1147 		}
1148 		break;
1149 	case hwmon_power:
1150 		switch (attr) {
1151 		case hwmon_power_label:
1152 			*str = sfp_hwmon_power_labels[channel];
1153 			return 0;
1154 		default:
1155 			return -EOPNOTSUPP;
1156 		}
1157 		break;
1158 	default:
1159 		return -EOPNOTSUPP;
1160 	}
1161 
1162 	return -EOPNOTSUPP;
1163 }
1164 
1165 static const struct hwmon_ops sfp_hwmon_ops = {
1166 	.is_visible = sfp_hwmon_is_visible,
1167 	.read = sfp_hwmon_read,
1168 	.read_string = sfp_hwmon_read_string,
1169 };
1170 
1171 static u32 sfp_hwmon_chip_config[] = {
1172 	HWMON_C_REGISTER_TZ,
1173 	0,
1174 };
1175 
1176 static const struct hwmon_channel_info sfp_hwmon_chip = {
1177 	.type = hwmon_chip,
1178 	.config = sfp_hwmon_chip_config,
1179 };
1180 
1181 static u32 sfp_hwmon_temp_config[] = {
1182 	HWMON_T_INPUT |
1183 	HWMON_T_MAX | HWMON_T_MIN |
1184 	HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1185 	HWMON_T_CRIT | HWMON_T_LCRIT |
1186 	HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1187 	HWMON_T_LABEL,
1188 	0,
1189 };
1190 
1191 static const struct hwmon_channel_info sfp_hwmon_temp_channel_info = {
1192 	.type = hwmon_temp,
1193 	.config = sfp_hwmon_temp_config,
1194 };
1195 
1196 static u32 sfp_hwmon_vcc_config[] = {
1197 	HWMON_I_INPUT |
1198 	HWMON_I_MAX | HWMON_I_MIN |
1199 	HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1200 	HWMON_I_CRIT | HWMON_I_LCRIT |
1201 	HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1202 	HWMON_I_LABEL,
1203 	0,
1204 };
1205 
1206 static const struct hwmon_channel_info sfp_hwmon_vcc_channel_info = {
1207 	.type = hwmon_in,
1208 	.config = sfp_hwmon_vcc_config,
1209 };
1210 
1211 static u32 sfp_hwmon_bias_config[] = {
1212 	HWMON_C_INPUT |
1213 	HWMON_C_MAX | HWMON_C_MIN |
1214 	HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1215 	HWMON_C_CRIT | HWMON_C_LCRIT |
1216 	HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1217 	HWMON_C_LABEL,
1218 	0,
1219 };
1220 
1221 static const struct hwmon_channel_info sfp_hwmon_bias_channel_info = {
1222 	.type = hwmon_curr,
1223 	.config = sfp_hwmon_bias_config,
1224 };
1225 
1226 static u32 sfp_hwmon_power_config[] = {
1227 	/* Transmit power */
1228 	HWMON_P_INPUT |
1229 	HWMON_P_MAX | HWMON_P_MIN |
1230 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1231 	HWMON_P_CRIT | HWMON_P_LCRIT |
1232 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1233 	HWMON_P_LABEL,
1234 	/* Receive power */
1235 	HWMON_P_INPUT |
1236 	HWMON_P_MAX | HWMON_P_MIN |
1237 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1238 	HWMON_P_CRIT | HWMON_P_LCRIT |
1239 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1240 	HWMON_P_LABEL,
1241 	0,
1242 };
1243 
1244 static const struct hwmon_channel_info sfp_hwmon_power_channel_info = {
1245 	.type = hwmon_power,
1246 	.config = sfp_hwmon_power_config,
1247 };
1248 
1249 static const struct hwmon_channel_info *sfp_hwmon_info[] = {
1250 	&sfp_hwmon_chip,
1251 	&sfp_hwmon_vcc_channel_info,
1252 	&sfp_hwmon_temp_channel_info,
1253 	&sfp_hwmon_bias_channel_info,
1254 	&sfp_hwmon_power_channel_info,
1255 	NULL,
1256 };
1257 
1258 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1259 	.ops = &sfp_hwmon_ops,
1260 	.info = sfp_hwmon_info,
1261 };
1262 
1263 static void sfp_hwmon_probe(struct work_struct *work)
1264 {
1265 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1266 	int err, i;
1267 
1268 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1269 	if (err < 0) {
1270 		if (sfp->hwmon_tries--) {
1271 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1272 					 T_PROBE_RETRY_SLOW);
1273 		} else {
1274 			dev_warn(sfp->dev, "hwmon probe failed: %d\n", err);
1275 		}
1276 		return;
1277 	}
1278 
1279 	sfp->hwmon_name = kstrdup(dev_name(sfp->dev), GFP_KERNEL);
1280 	if (!sfp->hwmon_name) {
1281 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1282 		return;
1283 	}
1284 
1285 	for (i = 0; sfp->hwmon_name[i]; i++)
1286 		if (hwmon_is_bad_char(sfp->hwmon_name[i]))
1287 			sfp->hwmon_name[i] = '_';
1288 
1289 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1290 							 sfp->hwmon_name, sfp,
1291 							 &sfp_hwmon_chip_info,
1292 							 NULL);
1293 	if (IS_ERR(sfp->hwmon_dev))
1294 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1295 			PTR_ERR(sfp->hwmon_dev));
1296 }
1297 
1298 static int sfp_hwmon_insert(struct sfp *sfp)
1299 {
1300 	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
1301 		return 0;
1302 
1303 	if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
1304 		return 0;
1305 
1306 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1307 		/* This driver in general does not support address
1308 		 * change.
1309 		 */
1310 		return 0;
1311 
1312 	mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1313 	sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1314 
1315 	return 0;
1316 }
1317 
1318 static void sfp_hwmon_remove(struct sfp *sfp)
1319 {
1320 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1321 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1322 		hwmon_device_unregister(sfp->hwmon_dev);
1323 		sfp->hwmon_dev = NULL;
1324 		kfree(sfp->hwmon_name);
1325 	}
1326 }
1327 
1328 static int sfp_hwmon_init(struct sfp *sfp)
1329 {
1330 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1331 
1332 	return 0;
1333 }
1334 
1335 static void sfp_hwmon_exit(struct sfp *sfp)
1336 {
1337 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1338 }
1339 #else
1340 static int sfp_hwmon_insert(struct sfp *sfp)
1341 {
1342 	return 0;
1343 }
1344 
1345 static void sfp_hwmon_remove(struct sfp *sfp)
1346 {
1347 }
1348 
1349 static int sfp_hwmon_init(struct sfp *sfp)
1350 {
1351 	return 0;
1352 }
1353 
1354 static void sfp_hwmon_exit(struct sfp *sfp)
1355 {
1356 }
1357 #endif
1358 
1359 /* Helpers */
1360 static void sfp_module_tx_disable(struct sfp *sfp)
1361 {
1362 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1363 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1364 	sfp->state |= SFP_F_TX_DISABLE;
1365 	sfp_set_state(sfp, sfp->state);
1366 }
1367 
1368 static void sfp_module_tx_enable(struct sfp *sfp)
1369 {
1370 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1371 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1372 	sfp->state &= ~SFP_F_TX_DISABLE;
1373 	sfp_set_state(sfp, sfp->state);
1374 }
1375 
1376 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1377 {
1378 	unsigned int state = sfp->state;
1379 
1380 	if (state & SFP_F_TX_DISABLE)
1381 		return;
1382 
1383 	sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1384 
1385 	udelay(T_RESET_US);
1386 
1387 	sfp_set_state(sfp, state);
1388 }
1389 
1390 /* SFP state machine */
1391 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1392 {
1393 	if (timeout)
1394 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1395 				 timeout);
1396 	else
1397 		cancel_delayed_work(&sfp->timeout);
1398 }
1399 
1400 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1401 			unsigned int timeout)
1402 {
1403 	sfp->sm_state = state;
1404 	sfp_sm_set_timer(sfp, timeout);
1405 }
1406 
1407 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1408 			    unsigned int timeout)
1409 {
1410 	sfp->sm_mod_state = state;
1411 	sfp_sm_set_timer(sfp, timeout);
1412 }
1413 
1414 static void sfp_sm_phy_detach(struct sfp *sfp)
1415 {
1416 	sfp_remove_phy(sfp->sfp_bus);
1417 	phy_device_remove(sfp->mod_phy);
1418 	phy_device_free(sfp->mod_phy);
1419 	sfp->mod_phy = NULL;
1420 }
1421 
1422 static int sfp_sm_probe_phy(struct sfp *sfp, bool is_c45)
1423 {
1424 	struct phy_device *phy;
1425 	int err;
1426 
1427 	phy = get_phy_device(sfp->i2c_mii, SFP_PHY_ADDR, is_c45);
1428 	if (phy == ERR_PTR(-ENODEV))
1429 		return PTR_ERR(phy);
1430 	if (IS_ERR(phy)) {
1431 		dev_err(sfp->dev, "mdiobus scan returned %ld\n", PTR_ERR(phy));
1432 		return PTR_ERR(phy);
1433 	}
1434 
1435 	err = phy_device_register(phy);
1436 	if (err) {
1437 		phy_device_free(phy);
1438 		dev_err(sfp->dev, "phy_device_register failed: %d\n", err);
1439 		return err;
1440 	}
1441 
1442 	err = sfp_add_phy(sfp->sfp_bus, phy);
1443 	if (err) {
1444 		phy_device_remove(phy);
1445 		phy_device_free(phy);
1446 		dev_err(sfp->dev, "sfp_add_phy failed: %d\n", err);
1447 		return err;
1448 	}
1449 
1450 	sfp->mod_phy = phy;
1451 
1452 	return 0;
1453 }
1454 
1455 static void sfp_sm_link_up(struct sfp *sfp)
1456 {
1457 	sfp_link_up(sfp->sfp_bus);
1458 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1459 }
1460 
1461 static void sfp_sm_link_down(struct sfp *sfp)
1462 {
1463 	sfp_link_down(sfp->sfp_bus);
1464 }
1465 
1466 static void sfp_sm_link_check_los(struct sfp *sfp)
1467 {
1468 	unsigned int los = sfp->state & SFP_F_LOS;
1469 
1470 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1471 	 * are set, we assume that no LOS signal is available.
1472 	 */
1473 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED))
1474 		los ^= SFP_F_LOS;
1475 	else if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL)))
1476 		los = 0;
1477 
1478 	if (los)
1479 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1480 	else
1481 		sfp_sm_link_up(sfp);
1482 }
1483 
1484 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1485 {
1486 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1487 		event == SFP_E_LOS_LOW) ||
1488 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1489 		event == SFP_E_LOS_HIGH);
1490 }
1491 
1492 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1493 {
1494 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1495 		event == SFP_E_LOS_HIGH) ||
1496 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1497 		event == SFP_E_LOS_LOW);
1498 }
1499 
1500 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1501 {
1502 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
1503 		dev_err(sfp->dev,
1504 			"module persistently indicates fault, disabling\n");
1505 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1506 	} else {
1507 		if (warn)
1508 			dev_err(sfp->dev, "module transmit fault indicated\n");
1509 
1510 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1511 	}
1512 }
1513 
1514 /* Probe a SFP for a PHY device if the module supports copper - the PHY
1515  * normally sits at I2C bus address 0x56, and may either be a clause 22
1516  * or clause 45 PHY.
1517  *
1518  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
1519  * negotiation enabled, but some may be in 1000base-X - which is for the
1520  * PHY driver to determine.
1521  *
1522  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
1523  * mode according to the negotiated line speed.
1524  */
1525 static int sfp_sm_probe_for_phy(struct sfp *sfp)
1526 {
1527 	int err = 0;
1528 
1529 	switch (sfp->id.base.extended_cc) {
1530 	case SFF8024_ECC_10GBASE_T_SFI:
1531 	case SFF8024_ECC_10GBASE_T_SR:
1532 	case SFF8024_ECC_5GBASE_T:
1533 	case SFF8024_ECC_2_5GBASE_T:
1534 		err = sfp_sm_probe_phy(sfp, true);
1535 		break;
1536 
1537 	default:
1538 		if (sfp->id.base.e1000_base_t)
1539 			err = sfp_sm_probe_phy(sfp, false);
1540 		break;
1541 	}
1542 	return err;
1543 }
1544 
1545 static int sfp_module_parse_power(struct sfp *sfp)
1546 {
1547 	u32 power_mW = 1000;
1548 
1549 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1550 		power_mW = 1500;
1551 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1552 		power_mW = 2000;
1553 
1554 	if (power_mW > sfp->max_power_mW) {
1555 		/* Module power specification exceeds the allowed maximum. */
1556 		if (sfp->id.ext.sff8472_compliance ==
1557 			SFP_SFF8472_COMPLIANCE_NONE &&
1558 		    !(sfp->id.ext.diagmon & SFP_DIAGMON_DDM)) {
1559 			/* The module appears not to implement bus address
1560 			 * 0xa2, so assume that the module powers up in the
1561 			 * indicated mode.
1562 			 */
1563 			dev_err(sfp->dev,
1564 				"Host does not support %u.%uW modules\n",
1565 				power_mW / 1000, (power_mW / 100) % 10);
1566 			return -EINVAL;
1567 		} else {
1568 			dev_warn(sfp->dev,
1569 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1570 				 power_mW / 1000, (power_mW / 100) % 10);
1571 			return 0;
1572 		}
1573 	}
1574 
1575 	/* If the module requires a higher power mode, but also requires
1576 	 * an address change sequence, warn the user that the module may
1577 	 * not be functional.
1578 	 */
1579 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE && power_mW > 1000) {
1580 		dev_warn(sfp->dev,
1581 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1582 			 power_mW / 1000, (power_mW / 100) % 10);
1583 		return 0;
1584 	}
1585 
1586 	sfp->module_power_mW = power_mW;
1587 
1588 	return 0;
1589 }
1590 
1591 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1592 {
1593 	u8 val;
1594 	int err;
1595 
1596 	err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1597 	if (err != sizeof(val)) {
1598 		dev_err(sfp->dev, "Failed to read EEPROM: %d\n", err);
1599 		return -EAGAIN;
1600 	}
1601 
1602 	/* DM7052 reports as a high power module, responds to reads (with
1603 	 * all bytes 0xff) at 0x51 but does not accept writes.  In any case,
1604 	 * if the bit is already set, we're already in high power mode.
1605 	 */
1606 	if (!!(val & BIT(0)) == enable)
1607 		return 0;
1608 
1609 	if (enable)
1610 		val |= BIT(0);
1611 	else
1612 		val &= ~BIT(0);
1613 
1614 	err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1615 	if (err != sizeof(val)) {
1616 		dev_err(sfp->dev, "Failed to write EEPROM: %d\n", err);
1617 		return -EAGAIN;
1618 	}
1619 
1620 	if (enable)
1621 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1622 			 sfp->module_power_mW / 1000,
1623 			 (sfp->module_power_mW / 100) % 10);
1624 
1625 	return 0;
1626 }
1627 
1628 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
1629 {
1630 	/* SFP module inserted - read I2C data */
1631 	struct sfp_eeprom_id id;
1632 	bool cotsworks;
1633 	u8 check;
1634 	int ret;
1635 
1636 	ret = sfp_read(sfp, false, 0, &id, sizeof(id));
1637 	if (ret < 0) {
1638 		if (report)
1639 			dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
1640 		return -EAGAIN;
1641 	}
1642 
1643 	if (ret != sizeof(id)) {
1644 		dev_err(sfp->dev, "EEPROM short read: %d\n", ret);
1645 		return -EAGAIN;
1646 	}
1647 
1648 	/* Cotsworks do not seem to update the checksums when they
1649 	 * do the final programming with the final module part number,
1650 	 * serial number and date code.
1651 	 */
1652 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
1653 
1654 	/* Validate the checksum over the base structure */
1655 	check = sfp_check(&id.base, sizeof(id.base) - 1);
1656 	if (check != id.base.cc_base) {
1657 		if (cotsworks) {
1658 			dev_warn(sfp->dev,
1659 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
1660 				 check, id.base.cc_base);
1661 		} else {
1662 			dev_err(sfp->dev,
1663 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
1664 				check, id.base.cc_base);
1665 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1666 				       16, 1, &id, sizeof(id), true);
1667 			return -EINVAL;
1668 		}
1669 	}
1670 
1671 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
1672 	if (check != id.ext.cc_ext) {
1673 		if (cotsworks) {
1674 			dev_warn(sfp->dev,
1675 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
1676 				 check, id.ext.cc_ext);
1677 		} else {
1678 			dev_err(sfp->dev,
1679 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
1680 				check, id.ext.cc_ext);
1681 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1682 				       16, 1, &id, sizeof(id), true);
1683 			memset(&id.ext, 0, sizeof(id.ext));
1684 		}
1685 	}
1686 
1687 	sfp->id = id;
1688 
1689 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
1690 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
1691 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
1692 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
1693 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
1694 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
1695 
1696 	/* Check whether we support this module */
1697 	if (!sfp->type->module_supported(&id)) {
1698 		dev_err(sfp->dev,
1699 			"module is not supported - phys id 0x%02x 0x%02x\n",
1700 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
1701 		return -EINVAL;
1702 	}
1703 
1704 	/* If the module requires address swap mode, warn about it */
1705 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1706 		dev_warn(sfp->dev,
1707 			 "module address swap to access page 0xA2 is not supported.\n");
1708 
1709 	/* Parse the module power requirement */
1710 	ret = sfp_module_parse_power(sfp);
1711 	if (ret < 0)
1712 		return ret;
1713 
1714 	if (!memcmp(id.base.vendor_name, "ALCATELLUCENT   ", 16) &&
1715 	    !memcmp(id.base.vendor_pn, "3FE46541AA      ", 16))
1716 		sfp->module_t_start_up = T_START_UP_BAD_GPON;
1717 	else
1718 		sfp->module_t_start_up = T_START_UP;
1719 
1720 	return 0;
1721 }
1722 
1723 static void sfp_sm_mod_remove(struct sfp *sfp)
1724 {
1725 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
1726 		sfp_module_remove(sfp->sfp_bus);
1727 
1728 	sfp_hwmon_remove(sfp);
1729 
1730 	memset(&sfp->id, 0, sizeof(sfp->id));
1731 	sfp->module_power_mW = 0;
1732 
1733 	dev_info(sfp->dev, "module removed\n");
1734 }
1735 
1736 /* This state machine tracks the upstream's state */
1737 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
1738 {
1739 	switch (sfp->sm_dev_state) {
1740 	default:
1741 		if (event == SFP_E_DEV_ATTACH)
1742 			sfp->sm_dev_state = SFP_DEV_DOWN;
1743 		break;
1744 
1745 	case SFP_DEV_DOWN:
1746 		if (event == SFP_E_DEV_DETACH)
1747 			sfp->sm_dev_state = SFP_DEV_DETACHED;
1748 		else if (event == SFP_E_DEV_UP)
1749 			sfp->sm_dev_state = SFP_DEV_UP;
1750 		break;
1751 
1752 	case SFP_DEV_UP:
1753 		if (event == SFP_E_DEV_DETACH)
1754 			sfp->sm_dev_state = SFP_DEV_DETACHED;
1755 		else if (event == SFP_E_DEV_DOWN)
1756 			sfp->sm_dev_state = SFP_DEV_DOWN;
1757 		break;
1758 	}
1759 }
1760 
1761 /* This state machine tracks the insert/remove state of the module, probes
1762  * the on-board EEPROM, and sets up the power level.
1763  */
1764 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
1765 {
1766 	int err;
1767 
1768 	/* Handle remove event globally, it resets this state machine */
1769 	if (event == SFP_E_REMOVE) {
1770 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
1771 			sfp_sm_mod_remove(sfp);
1772 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
1773 		return;
1774 	}
1775 
1776 	/* Handle device detach globally */
1777 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
1778 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
1779 		if (sfp->module_power_mW > 1000 &&
1780 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
1781 			sfp_sm_mod_hpower(sfp, false);
1782 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
1783 		return;
1784 	}
1785 
1786 	switch (sfp->sm_mod_state) {
1787 	default:
1788 		if (event == SFP_E_INSERT) {
1789 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
1790 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
1791 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
1792 		}
1793 		break;
1794 
1795 	case SFP_MOD_PROBE:
1796 		/* Wait for T_PROBE_INIT to time out */
1797 		if (event != SFP_E_TIMEOUT)
1798 			break;
1799 
1800 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
1801 		if (err == -EAGAIN) {
1802 			if (sfp->sm_mod_tries_init &&
1803 			   --sfp->sm_mod_tries_init) {
1804 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
1805 				break;
1806 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
1807 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
1808 					dev_warn(sfp->dev,
1809 						 "please wait, module slow to respond\n");
1810 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
1811 				break;
1812 			}
1813 		}
1814 		if (err < 0) {
1815 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1816 			break;
1817 		}
1818 
1819 		err = sfp_hwmon_insert(sfp);
1820 		if (err)
1821 			dev_warn(sfp->dev, "hwmon probe failed: %d\n", err);
1822 
1823 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
1824 		/* fall through */
1825 	case SFP_MOD_WAITDEV:
1826 		/* Ensure that the device is attached before proceeding */
1827 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
1828 			break;
1829 
1830 		/* Report the module insertion to the upstream device */
1831 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id);
1832 		if (err < 0) {
1833 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1834 			break;
1835 		}
1836 
1837 		/* If this is a power level 1 module, we are done */
1838 		if (sfp->module_power_mW <= 1000)
1839 			goto insert;
1840 
1841 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
1842 		/* fall through */
1843 	case SFP_MOD_HPOWER:
1844 		/* Enable high power mode */
1845 		err = sfp_sm_mod_hpower(sfp, true);
1846 		if (err < 0) {
1847 			if (err != -EAGAIN) {
1848 				sfp_module_remove(sfp->sfp_bus);
1849 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1850 			} else {
1851 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
1852 			}
1853 			break;
1854 		}
1855 
1856 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
1857 		break;
1858 
1859 	case SFP_MOD_WAITPWR:
1860 		/* Wait for T_HPOWER_LEVEL to time out */
1861 		if (event != SFP_E_TIMEOUT)
1862 			break;
1863 
1864 	insert:
1865 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
1866 		break;
1867 
1868 	case SFP_MOD_PRESENT:
1869 	case SFP_MOD_ERROR:
1870 		break;
1871 	}
1872 }
1873 
1874 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
1875 {
1876 	unsigned long timeout;
1877 	int ret;
1878 
1879 	/* Some events are global */
1880 	if (sfp->sm_state != SFP_S_DOWN &&
1881 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
1882 	     sfp->sm_dev_state != SFP_DEV_UP)) {
1883 		if (sfp->sm_state == SFP_S_LINK_UP &&
1884 		    sfp->sm_dev_state == SFP_DEV_UP)
1885 			sfp_sm_link_down(sfp);
1886 		if (sfp->sm_state > SFP_S_INIT)
1887 			sfp_module_stop(sfp->sfp_bus);
1888 		if (sfp->mod_phy)
1889 			sfp_sm_phy_detach(sfp);
1890 		sfp_module_tx_disable(sfp);
1891 		sfp_soft_stop_poll(sfp);
1892 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
1893 		return;
1894 	}
1895 
1896 	/* The main state machine */
1897 	switch (sfp->sm_state) {
1898 	case SFP_S_DOWN:
1899 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
1900 		    sfp->sm_dev_state != SFP_DEV_UP)
1901 			break;
1902 
1903 		if (!(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE))
1904 			sfp_soft_start_poll(sfp);
1905 
1906 		sfp_module_tx_enable(sfp);
1907 
1908 		/* Initialise the fault clearance retries */
1909 		sfp->sm_fault_retries = N_FAULT_INIT;
1910 
1911 		/* We need to check the TX_FAULT state, which is not defined
1912 		 * while TX_DISABLE is asserted. The earliest we want to do
1913 		 * anything (such as probe for a PHY) is 50ms.
1914 		 */
1915 		sfp_sm_next(sfp, SFP_S_WAIT, T_WAIT);
1916 		break;
1917 
1918 	case SFP_S_WAIT:
1919 		if (event != SFP_E_TIMEOUT)
1920 			break;
1921 
1922 		if (sfp->state & SFP_F_TX_FAULT) {
1923 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
1924 			 * from the TX_DISABLE deassertion for the module to
1925 			 * initialise, which is indicated by TX_FAULT
1926 			 * deasserting.
1927 			 */
1928 			timeout = sfp->module_t_start_up;
1929 			if (timeout > T_WAIT)
1930 				timeout -= T_WAIT;
1931 			else
1932 				timeout = 1;
1933 
1934 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
1935 		} else {
1936 			/* TX_FAULT is not asserted, assume the module has
1937 			 * finished initialising.
1938 			 */
1939 			goto init_done;
1940 		}
1941 		break;
1942 
1943 	case SFP_S_INIT:
1944 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
1945 			/* TX_FAULT is still asserted after t_init or
1946 			 * or t_start_up, so assume there is a fault.
1947 			 */
1948 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
1949 				     sfp->sm_fault_retries == N_FAULT_INIT);
1950 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
1951 	init_done:
1952 			sfp->sm_phy_retries = R_PHY_RETRY;
1953 			goto phy_probe;
1954 		}
1955 		break;
1956 
1957 	case SFP_S_INIT_PHY:
1958 		if (event != SFP_E_TIMEOUT)
1959 			break;
1960 	phy_probe:
1961 		/* TX_FAULT deasserted or we timed out with TX_FAULT
1962 		 * clear.  Probe for the PHY and check the LOS state.
1963 		 */
1964 		ret = sfp_sm_probe_for_phy(sfp);
1965 		if (ret == -ENODEV) {
1966 			if (--sfp->sm_phy_retries) {
1967 				sfp_sm_next(sfp, SFP_S_INIT_PHY, T_PHY_RETRY);
1968 				break;
1969 			} else {
1970 				dev_info(sfp->dev, "no PHY detected\n");
1971 			}
1972 		} else if (ret) {
1973 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
1974 			break;
1975 		}
1976 		if (sfp_module_start(sfp->sfp_bus)) {
1977 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
1978 			break;
1979 		}
1980 		sfp_sm_link_check_los(sfp);
1981 
1982 		/* Reset the fault retry count */
1983 		sfp->sm_fault_retries = N_FAULT;
1984 		break;
1985 
1986 	case SFP_S_INIT_TX_FAULT:
1987 		if (event == SFP_E_TIMEOUT) {
1988 			sfp_module_tx_fault_reset(sfp);
1989 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
1990 		}
1991 		break;
1992 
1993 	case SFP_S_WAIT_LOS:
1994 		if (event == SFP_E_TX_FAULT)
1995 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
1996 		else if (sfp_los_event_inactive(sfp, event))
1997 			sfp_sm_link_up(sfp);
1998 		break;
1999 
2000 	case SFP_S_LINK_UP:
2001 		if (event == SFP_E_TX_FAULT) {
2002 			sfp_sm_link_down(sfp);
2003 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2004 		} else if (sfp_los_event_active(sfp, event)) {
2005 			sfp_sm_link_down(sfp);
2006 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2007 		}
2008 		break;
2009 
2010 	case SFP_S_TX_FAULT:
2011 		if (event == SFP_E_TIMEOUT) {
2012 			sfp_module_tx_fault_reset(sfp);
2013 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2014 		}
2015 		break;
2016 
2017 	case SFP_S_REINIT:
2018 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2019 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2020 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2021 			dev_info(sfp->dev, "module transmit fault recovered\n");
2022 			sfp_sm_link_check_los(sfp);
2023 		}
2024 		break;
2025 
2026 	case SFP_S_TX_DISABLE:
2027 		break;
2028 	}
2029 }
2030 
2031 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
2032 {
2033 	mutex_lock(&sfp->sm_mutex);
2034 
2035 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
2036 		mod_state_to_str(sfp->sm_mod_state),
2037 		dev_state_to_str(sfp->sm_dev_state),
2038 		sm_state_to_str(sfp->sm_state),
2039 		event_to_str(event));
2040 
2041 	sfp_sm_device(sfp, event);
2042 	sfp_sm_module(sfp, event);
2043 	sfp_sm_main(sfp, event);
2044 
2045 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
2046 		mod_state_to_str(sfp->sm_mod_state),
2047 		dev_state_to_str(sfp->sm_dev_state),
2048 		sm_state_to_str(sfp->sm_state));
2049 
2050 	mutex_unlock(&sfp->sm_mutex);
2051 }
2052 
2053 static void sfp_attach(struct sfp *sfp)
2054 {
2055 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
2056 }
2057 
2058 static void sfp_detach(struct sfp *sfp)
2059 {
2060 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
2061 }
2062 
2063 static void sfp_start(struct sfp *sfp)
2064 {
2065 	sfp_sm_event(sfp, SFP_E_DEV_UP);
2066 }
2067 
2068 static void sfp_stop(struct sfp *sfp)
2069 {
2070 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
2071 }
2072 
2073 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2074 {
2075 	/* locking... and check module is present */
2076 
2077 	if (sfp->id.ext.sff8472_compliance &&
2078 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2079 		modinfo->type = ETH_MODULE_SFF_8472;
2080 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2081 	} else {
2082 		modinfo->type = ETH_MODULE_SFF_8079;
2083 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2084 	}
2085 	return 0;
2086 }
2087 
2088 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2089 			     u8 *data)
2090 {
2091 	unsigned int first, last, len;
2092 	int ret;
2093 
2094 	if (ee->len == 0)
2095 		return -EINVAL;
2096 
2097 	first = ee->offset;
2098 	last = ee->offset + ee->len;
2099 	if (first < ETH_MODULE_SFF_8079_LEN) {
2100 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2101 		len -= first;
2102 
2103 		ret = sfp_read(sfp, false, first, data, len);
2104 		if (ret < 0)
2105 			return ret;
2106 
2107 		first += len;
2108 		data += len;
2109 	}
2110 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2111 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2112 		len -= first;
2113 		first -= ETH_MODULE_SFF_8079_LEN;
2114 
2115 		ret = sfp_read(sfp, true, first, data, len);
2116 		if (ret < 0)
2117 			return ret;
2118 	}
2119 	return 0;
2120 }
2121 
2122 static const struct sfp_socket_ops sfp_module_ops = {
2123 	.attach = sfp_attach,
2124 	.detach = sfp_detach,
2125 	.start = sfp_start,
2126 	.stop = sfp_stop,
2127 	.module_info = sfp_module_info,
2128 	.module_eeprom = sfp_module_eeprom,
2129 };
2130 
2131 static void sfp_timeout(struct work_struct *work)
2132 {
2133 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2134 
2135 	rtnl_lock();
2136 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2137 	rtnl_unlock();
2138 }
2139 
2140 static void sfp_check_state(struct sfp *sfp)
2141 {
2142 	unsigned int state, i, changed;
2143 
2144 	mutex_lock(&sfp->st_mutex);
2145 	state = sfp_get_state(sfp);
2146 	changed = state ^ sfp->state;
2147 	changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2148 
2149 	for (i = 0; i < GPIO_MAX; i++)
2150 		if (changed & BIT(i))
2151 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_of_names[i],
2152 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2153 
2154 	state |= sfp->state & (SFP_F_TX_DISABLE | SFP_F_RATE_SELECT);
2155 	sfp->state = state;
2156 
2157 	rtnl_lock();
2158 	if (changed & SFP_F_PRESENT)
2159 		sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2160 				SFP_E_INSERT : SFP_E_REMOVE);
2161 
2162 	if (changed & SFP_F_TX_FAULT)
2163 		sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2164 				SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2165 
2166 	if (changed & SFP_F_LOS)
2167 		sfp_sm_event(sfp, state & SFP_F_LOS ?
2168 				SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2169 	rtnl_unlock();
2170 	mutex_unlock(&sfp->st_mutex);
2171 }
2172 
2173 static irqreturn_t sfp_irq(int irq, void *data)
2174 {
2175 	struct sfp *sfp = data;
2176 
2177 	sfp_check_state(sfp);
2178 
2179 	return IRQ_HANDLED;
2180 }
2181 
2182 static void sfp_poll(struct work_struct *work)
2183 {
2184 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2185 
2186 	sfp_check_state(sfp);
2187 
2188 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2189 	    sfp->need_poll)
2190 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2191 }
2192 
2193 static struct sfp *sfp_alloc(struct device *dev)
2194 {
2195 	struct sfp *sfp;
2196 
2197 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2198 	if (!sfp)
2199 		return ERR_PTR(-ENOMEM);
2200 
2201 	sfp->dev = dev;
2202 
2203 	mutex_init(&sfp->sm_mutex);
2204 	mutex_init(&sfp->st_mutex);
2205 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2206 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2207 
2208 	sfp_hwmon_init(sfp);
2209 
2210 	return sfp;
2211 }
2212 
2213 static void sfp_cleanup(void *data)
2214 {
2215 	struct sfp *sfp = data;
2216 
2217 	sfp_hwmon_exit(sfp);
2218 
2219 	cancel_delayed_work_sync(&sfp->poll);
2220 	cancel_delayed_work_sync(&sfp->timeout);
2221 	if (sfp->i2c_mii) {
2222 		mdiobus_unregister(sfp->i2c_mii);
2223 		mdiobus_free(sfp->i2c_mii);
2224 	}
2225 	if (sfp->i2c)
2226 		i2c_put_adapter(sfp->i2c);
2227 	kfree(sfp);
2228 }
2229 
2230 static int sfp_probe(struct platform_device *pdev)
2231 {
2232 	const struct sff_data *sff;
2233 	struct i2c_adapter *i2c;
2234 	struct sfp *sfp;
2235 	int err, i;
2236 
2237 	sfp = sfp_alloc(&pdev->dev);
2238 	if (IS_ERR(sfp))
2239 		return PTR_ERR(sfp);
2240 
2241 	platform_set_drvdata(pdev, sfp);
2242 
2243 	err = devm_add_action(sfp->dev, sfp_cleanup, sfp);
2244 	if (err < 0)
2245 		return err;
2246 
2247 	sff = sfp->type = &sfp_data;
2248 
2249 	if (pdev->dev.of_node) {
2250 		struct device_node *node = pdev->dev.of_node;
2251 		const struct of_device_id *id;
2252 		struct device_node *np;
2253 
2254 		id = of_match_node(sfp_of_match, node);
2255 		if (WARN_ON(!id))
2256 			return -EINVAL;
2257 
2258 		sff = sfp->type = id->data;
2259 
2260 		np = of_parse_phandle(node, "i2c-bus", 0);
2261 		if (!np) {
2262 			dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2263 			return -ENODEV;
2264 		}
2265 
2266 		i2c = of_find_i2c_adapter_by_node(np);
2267 		of_node_put(np);
2268 	} else if (has_acpi_companion(&pdev->dev)) {
2269 		struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
2270 		struct fwnode_handle *fw = acpi_fwnode_handle(adev);
2271 		struct fwnode_reference_args args;
2272 		struct acpi_handle *acpi_handle;
2273 		int ret;
2274 
2275 		ret = acpi_node_get_property_reference(fw, "i2c-bus", 0, &args);
2276 		if (ret || !is_acpi_device_node(args.fwnode)) {
2277 			dev_err(&pdev->dev, "missing 'i2c-bus' property\n");
2278 			return -ENODEV;
2279 		}
2280 
2281 		acpi_handle = ACPI_HANDLE_FWNODE(args.fwnode);
2282 		i2c = i2c_acpi_find_adapter_by_handle(acpi_handle);
2283 	} else {
2284 		return -EINVAL;
2285 	}
2286 
2287 	if (!i2c)
2288 		return -EPROBE_DEFER;
2289 
2290 	err = sfp_i2c_configure(sfp, i2c);
2291 	if (err < 0) {
2292 		i2c_put_adapter(i2c);
2293 		return err;
2294 	}
2295 
2296 	for (i = 0; i < GPIO_MAX; i++)
2297 		if (sff->gpios & BIT(i)) {
2298 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
2299 					   gpio_of_names[i], gpio_flags[i]);
2300 			if (IS_ERR(sfp->gpio[i]))
2301 				return PTR_ERR(sfp->gpio[i]);
2302 		}
2303 
2304 	sfp->get_state = sfp_gpio_get_state;
2305 	sfp->set_state = sfp_gpio_set_state;
2306 
2307 	/* Modules that have no detect signal are always present */
2308 	if (!(sfp->gpio[GPIO_MODDEF0]))
2309 		sfp->get_state = sff_gpio_get_state;
2310 
2311 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
2312 				 &sfp->max_power_mW);
2313 	if (!sfp->max_power_mW)
2314 		sfp->max_power_mW = 1000;
2315 
2316 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
2317 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
2318 
2319 	/* Get the initial state, and always signal TX disable,
2320 	 * since the network interface will not be up.
2321 	 */
2322 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
2323 
2324 	if (sfp->gpio[GPIO_RATE_SELECT] &&
2325 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RATE_SELECT]))
2326 		sfp->state |= SFP_F_RATE_SELECT;
2327 	sfp_set_state(sfp, sfp->state);
2328 	sfp_module_tx_disable(sfp);
2329 	if (sfp->state & SFP_F_PRESENT) {
2330 		rtnl_lock();
2331 		sfp_sm_event(sfp, SFP_E_INSERT);
2332 		rtnl_unlock();
2333 	}
2334 
2335 	for (i = 0; i < GPIO_MAX; i++) {
2336 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
2337 			continue;
2338 
2339 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
2340 		if (!sfp->gpio_irq[i]) {
2341 			sfp->need_poll = true;
2342 			continue;
2343 		}
2344 
2345 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
2346 						NULL, sfp_irq,
2347 						IRQF_ONESHOT |
2348 						IRQF_TRIGGER_RISING |
2349 						IRQF_TRIGGER_FALLING,
2350 						dev_name(sfp->dev), sfp);
2351 		if (err) {
2352 			sfp->gpio_irq[i] = 0;
2353 			sfp->need_poll = true;
2354 		}
2355 	}
2356 
2357 	if (sfp->need_poll)
2358 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2359 
2360 	/* We could have an issue in cases no Tx disable pin is available or
2361 	 * wired as modules using a laser as their light source will continue to
2362 	 * be active when the fiber is removed. This could be a safety issue and
2363 	 * we should at least warn the user about that.
2364 	 */
2365 	if (!sfp->gpio[GPIO_TX_DISABLE])
2366 		dev_warn(sfp->dev,
2367 			 "No tx_disable pin: SFP modules will always be emitting.\n");
2368 
2369 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
2370 	if (!sfp->sfp_bus)
2371 		return -ENOMEM;
2372 
2373 	return 0;
2374 }
2375 
2376 static int sfp_remove(struct platform_device *pdev)
2377 {
2378 	struct sfp *sfp = platform_get_drvdata(pdev);
2379 
2380 	sfp_unregister_socket(sfp->sfp_bus);
2381 
2382 	rtnl_lock();
2383 	sfp_sm_event(sfp, SFP_E_REMOVE);
2384 	rtnl_unlock();
2385 
2386 	return 0;
2387 }
2388 
2389 static void sfp_shutdown(struct platform_device *pdev)
2390 {
2391 	struct sfp *sfp = platform_get_drvdata(pdev);
2392 	int i;
2393 
2394 	for (i = 0; i < GPIO_MAX; i++) {
2395 		if (!sfp->gpio_irq[i])
2396 			continue;
2397 
2398 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
2399 	}
2400 
2401 	cancel_delayed_work_sync(&sfp->poll);
2402 	cancel_delayed_work_sync(&sfp->timeout);
2403 }
2404 
2405 static struct platform_driver sfp_driver = {
2406 	.probe = sfp_probe,
2407 	.remove = sfp_remove,
2408 	.shutdown = sfp_shutdown,
2409 	.driver = {
2410 		.name = "sfp",
2411 		.of_match_table = sfp_of_match,
2412 	},
2413 };
2414 
2415 static int sfp_init(void)
2416 {
2417 	poll_jiffies = msecs_to_jiffies(100);
2418 
2419 	return platform_driver_register(&sfp_driver);
2420 }
2421 module_init(sfp_init);
2422 
2423 static void sfp_exit(void)
2424 {
2425 	platform_driver_unregister(&sfp_driver);
2426 }
2427 module_exit(sfp_exit);
2428 
2429 MODULE_ALIAS("platform:sfp");
2430 MODULE_AUTHOR("Russell King");
2431 MODULE_LICENSE("GPL v2");
2432