xref: /linux/drivers/net/phy/sfp.c (revision 3a755ebcc2557e22b895b8976257f682c653db1d)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/acpi.h>
3 #include <linux/ctype.h>
4 #include <linux/debugfs.h>
5 #include <linux/delay.h>
6 #include <linux/gpio/consumer.h>
7 #include <linux/hwmon.h>
8 #include <linux/i2c.h>
9 #include <linux/interrupt.h>
10 #include <linux/jiffies.h>
11 #include <linux/mdio/mdio-i2c.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/of.h>
15 #include <linux/phy.h>
16 #include <linux/platform_device.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/slab.h>
19 #include <linux/workqueue.h>
20 
21 #include "sfp.h"
22 #include "swphy.h"
23 
24 enum {
25 	GPIO_MODDEF0,
26 	GPIO_LOS,
27 	GPIO_TX_FAULT,
28 	GPIO_TX_DISABLE,
29 	GPIO_RATE_SELECT,
30 	GPIO_MAX,
31 
32 	SFP_F_PRESENT = BIT(GPIO_MODDEF0),
33 	SFP_F_LOS = BIT(GPIO_LOS),
34 	SFP_F_TX_FAULT = BIT(GPIO_TX_FAULT),
35 	SFP_F_TX_DISABLE = BIT(GPIO_TX_DISABLE),
36 	SFP_F_RATE_SELECT = BIT(GPIO_RATE_SELECT),
37 
38 	SFP_E_INSERT = 0,
39 	SFP_E_REMOVE,
40 	SFP_E_DEV_ATTACH,
41 	SFP_E_DEV_DETACH,
42 	SFP_E_DEV_DOWN,
43 	SFP_E_DEV_UP,
44 	SFP_E_TX_FAULT,
45 	SFP_E_TX_CLEAR,
46 	SFP_E_LOS_HIGH,
47 	SFP_E_LOS_LOW,
48 	SFP_E_TIMEOUT,
49 
50 	SFP_MOD_EMPTY = 0,
51 	SFP_MOD_ERROR,
52 	SFP_MOD_PROBE,
53 	SFP_MOD_WAITDEV,
54 	SFP_MOD_HPOWER,
55 	SFP_MOD_WAITPWR,
56 	SFP_MOD_PRESENT,
57 
58 	SFP_DEV_DETACHED = 0,
59 	SFP_DEV_DOWN,
60 	SFP_DEV_UP,
61 
62 	SFP_S_DOWN = 0,
63 	SFP_S_FAIL,
64 	SFP_S_WAIT,
65 	SFP_S_INIT,
66 	SFP_S_INIT_PHY,
67 	SFP_S_INIT_TX_FAULT,
68 	SFP_S_WAIT_LOS,
69 	SFP_S_LINK_UP,
70 	SFP_S_TX_FAULT,
71 	SFP_S_REINIT,
72 	SFP_S_TX_DISABLE,
73 };
74 
75 static const char  * const mod_state_strings[] = {
76 	[SFP_MOD_EMPTY] = "empty",
77 	[SFP_MOD_ERROR] = "error",
78 	[SFP_MOD_PROBE] = "probe",
79 	[SFP_MOD_WAITDEV] = "waitdev",
80 	[SFP_MOD_HPOWER] = "hpower",
81 	[SFP_MOD_WAITPWR] = "waitpwr",
82 	[SFP_MOD_PRESENT] = "present",
83 };
84 
85 static const char *mod_state_to_str(unsigned short mod_state)
86 {
87 	if (mod_state >= ARRAY_SIZE(mod_state_strings))
88 		return "Unknown module state";
89 	return mod_state_strings[mod_state];
90 }
91 
92 static const char * const dev_state_strings[] = {
93 	[SFP_DEV_DETACHED] = "detached",
94 	[SFP_DEV_DOWN] = "down",
95 	[SFP_DEV_UP] = "up",
96 };
97 
98 static const char *dev_state_to_str(unsigned short dev_state)
99 {
100 	if (dev_state >= ARRAY_SIZE(dev_state_strings))
101 		return "Unknown device state";
102 	return dev_state_strings[dev_state];
103 }
104 
105 static const char * const event_strings[] = {
106 	[SFP_E_INSERT] = "insert",
107 	[SFP_E_REMOVE] = "remove",
108 	[SFP_E_DEV_ATTACH] = "dev_attach",
109 	[SFP_E_DEV_DETACH] = "dev_detach",
110 	[SFP_E_DEV_DOWN] = "dev_down",
111 	[SFP_E_DEV_UP] = "dev_up",
112 	[SFP_E_TX_FAULT] = "tx_fault",
113 	[SFP_E_TX_CLEAR] = "tx_clear",
114 	[SFP_E_LOS_HIGH] = "los_high",
115 	[SFP_E_LOS_LOW] = "los_low",
116 	[SFP_E_TIMEOUT] = "timeout",
117 };
118 
119 static const char *event_to_str(unsigned short event)
120 {
121 	if (event >= ARRAY_SIZE(event_strings))
122 		return "Unknown event";
123 	return event_strings[event];
124 }
125 
126 static const char * const sm_state_strings[] = {
127 	[SFP_S_DOWN] = "down",
128 	[SFP_S_FAIL] = "fail",
129 	[SFP_S_WAIT] = "wait",
130 	[SFP_S_INIT] = "init",
131 	[SFP_S_INIT_PHY] = "init_phy",
132 	[SFP_S_INIT_TX_FAULT] = "init_tx_fault",
133 	[SFP_S_WAIT_LOS] = "wait_los",
134 	[SFP_S_LINK_UP] = "link_up",
135 	[SFP_S_TX_FAULT] = "tx_fault",
136 	[SFP_S_REINIT] = "reinit",
137 	[SFP_S_TX_DISABLE] = "tx_disable",
138 };
139 
140 static const char *sm_state_to_str(unsigned short sm_state)
141 {
142 	if (sm_state >= ARRAY_SIZE(sm_state_strings))
143 		return "Unknown state";
144 	return sm_state_strings[sm_state];
145 }
146 
147 static const char *gpio_of_names[] = {
148 	"mod-def0",
149 	"los",
150 	"tx-fault",
151 	"tx-disable",
152 	"rate-select0",
153 };
154 
155 static const enum gpiod_flags gpio_flags[] = {
156 	GPIOD_IN,
157 	GPIOD_IN,
158 	GPIOD_IN,
159 	GPIOD_ASIS,
160 	GPIOD_ASIS,
161 };
162 
163 /* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
164  * non-cooled module to initialise its laser safety circuitry. We wait
165  * an initial T_WAIT period before we check the tx fault to give any PHY
166  * on board (for a copper SFP) time to initialise.
167  */
168 #define T_WAIT			msecs_to_jiffies(50)
169 #define T_START_UP		msecs_to_jiffies(300)
170 #define T_START_UP_BAD_GPON	msecs_to_jiffies(60000)
171 
172 /* t_reset is the time required to assert the TX_DISABLE signal to reset
173  * an indicated TX_FAULT.
174  */
175 #define T_RESET_US		10
176 #define T_FAULT_RECOVER		msecs_to_jiffies(1000)
177 
178 /* N_FAULT_INIT is the number of recovery attempts at module initialisation
179  * time. If the TX_FAULT signal is not deasserted after this number of
180  * attempts at clearing it, we decide that the module is faulty.
181  * N_FAULT is the same but after the module has initialised.
182  */
183 #define N_FAULT_INIT		5
184 #define N_FAULT			5
185 
186 /* T_PHY_RETRY is the time interval between attempts to probe the PHY.
187  * R_PHY_RETRY is the number of attempts.
188  */
189 #define T_PHY_RETRY		msecs_to_jiffies(50)
190 #define R_PHY_RETRY		12
191 
192 /* SFP module presence detection is poor: the three MOD DEF signals are
193  * the same length on the PCB, which means it's possible for MOD DEF 0 to
194  * connect before the I2C bus on MOD DEF 1/2.
195  *
196  * The SFF-8472 specifies t_serial ("Time from power on until module is
197  * ready for data transmission over the two wire serial bus.") as 300ms.
198  */
199 #define T_SERIAL		msecs_to_jiffies(300)
200 #define T_HPOWER_LEVEL		msecs_to_jiffies(300)
201 #define T_PROBE_RETRY_INIT	msecs_to_jiffies(100)
202 #define R_PROBE_RETRY_INIT	10
203 #define T_PROBE_RETRY_SLOW	msecs_to_jiffies(5000)
204 #define R_PROBE_RETRY_SLOW	12
205 
206 /* SFP modules appear to always have their PHY configured for bus address
207  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
208  */
209 #define SFP_PHY_ADDR	22
210 
211 struct sff_data {
212 	unsigned int gpios;
213 	bool (*module_supported)(const struct sfp_eeprom_id *id);
214 };
215 
216 struct sfp {
217 	struct device *dev;
218 	struct i2c_adapter *i2c;
219 	struct mii_bus *i2c_mii;
220 	struct sfp_bus *sfp_bus;
221 	struct phy_device *mod_phy;
222 	const struct sff_data *type;
223 	size_t i2c_block_size;
224 	u32 max_power_mW;
225 
226 	unsigned int (*get_state)(struct sfp *);
227 	void (*set_state)(struct sfp *, unsigned int);
228 	int (*read)(struct sfp *, bool, u8, void *, size_t);
229 	int (*write)(struct sfp *, bool, u8, void *, size_t);
230 
231 	struct gpio_desc *gpio[GPIO_MAX];
232 	int gpio_irq[GPIO_MAX];
233 
234 	bool need_poll;
235 
236 	struct mutex st_mutex;			/* Protects state */
237 	unsigned int state_soft_mask;
238 	unsigned int state;
239 	struct delayed_work poll;
240 	struct delayed_work timeout;
241 	struct mutex sm_mutex;			/* Protects state machine */
242 	unsigned char sm_mod_state;
243 	unsigned char sm_mod_tries_init;
244 	unsigned char sm_mod_tries;
245 	unsigned char sm_dev_state;
246 	unsigned short sm_state;
247 	unsigned char sm_fault_retries;
248 	unsigned char sm_phy_retries;
249 
250 	struct sfp_eeprom_id id;
251 	unsigned int module_power_mW;
252 	unsigned int module_t_start_up;
253 	bool tx_fault_ignore;
254 
255 #if IS_ENABLED(CONFIG_HWMON)
256 	struct sfp_diag diag;
257 	struct delayed_work hwmon_probe;
258 	unsigned int hwmon_tries;
259 	struct device *hwmon_dev;
260 	char *hwmon_name;
261 #endif
262 
263 #if IS_ENABLED(CONFIG_DEBUG_FS)
264 	struct dentry *debugfs_dir;
265 #endif
266 };
267 
268 static bool sff_module_supported(const struct sfp_eeprom_id *id)
269 {
270 	return id->base.phys_id == SFF8024_ID_SFF_8472 &&
271 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
272 }
273 
274 static const struct sff_data sff_data = {
275 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
276 	.module_supported = sff_module_supported,
277 };
278 
279 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
280 {
281 	if (id->base.phys_id == SFF8024_ID_SFP &&
282 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP)
283 		return true;
284 
285 	/* SFP GPON module Ubiquiti U-Fiber Instant has in its EEPROM stored
286 	 * phys id SFF instead of SFP. Therefore mark this module explicitly
287 	 * as supported based on vendor name and pn match.
288 	 */
289 	if (id->base.phys_id == SFF8024_ID_SFF_8472 &&
290 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP &&
291 	    !memcmp(id->base.vendor_name, "UBNT            ", 16) &&
292 	    !memcmp(id->base.vendor_pn, "UF-INSTANT      ", 16))
293 		return true;
294 
295 	return false;
296 }
297 
298 static const struct sff_data sfp_data = {
299 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
300 		 SFP_F_TX_DISABLE | SFP_F_RATE_SELECT,
301 	.module_supported = sfp_module_supported,
302 };
303 
304 static const struct of_device_id sfp_of_match[] = {
305 	{ .compatible = "sff,sff", .data = &sff_data, },
306 	{ .compatible = "sff,sfp", .data = &sfp_data, },
307 	{ },
308 };
309 MODULE_DEVICE_TABLE(of, sfp_of_match);
310 
311 static unsigned long poll_jiffies;
312 
313 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
314 {
315 	unsigned int i, state, v;
316 
317 	for (i = state = 0; i < GPIO_MAX; i++) {
318 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
319 			continue;
320 
321 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
322 		if (v)
323 			state |= BIT(i);
324 	}
325 
326 	return state;
327 }
328 
329 static unsigned int sff_gpio_get_state(struct sfp *sfp)
330 {
331 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
332 }
333 
334 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
335 {
336 	if (state & SFP_F_PRESENT) {
337 		/* If the module is present, drive the signals */
338 		if (sfp->gpio[GPIO_TX_DISABLE])
339 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
340 					       state & SFP_F_TX_DISABLE);
341 		if (state & SFP_F_RATE_SELECT)
342 			gpiod_direction_output(sfp->gpio[GPIO_RATE_SELECT],
343 					       state & SFP_F_RATE_SELECT);
344 	} else {
345 		/* Otherwise, let them float to the pull-ups */
346 		if (sfp->gpio[GPIO_TX_DISABLE])
347 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
348 		if (state & SFP_F_RATE_SELECT)
349 			gpiod_direction_input(sfp->gpio[GPIO_RATE_SELECT]);
350 	}
351 }
352 
353 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
354 			size_t len)
355 {
356 	struct i2c_msg msgs[2];
357 	u8 bus_addr = a2 ? 0x51 : 0x50;
358 	size_t block_size = sfp->i2c_block_size;
359 	size_t this_len;
360 	int ret;
361 
362 	msgs[0].addr = bus_addr;
363 	msgs[0].flags = 0;
364 	msgs[0].len = 1;
365 	msgs[0].buf = &dev_addr;
366 	msgs[1].addr = bus_addr;
367 	msgs[1].flags = I2C_M_RD;
368 	msgs[1].len = len;
369 	msgs[1].buf = buf;
370 
371 	while (len) {
372 		this_len = len;
373 		if (this_len > block_size)
374 			this_len = block_size;
375 
376 		msgs[1].len = this_len;
377 
378 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
379 		if (ret < 0)
380 			return ret;
381 
382 		if (ret != ARRAY_SIZE(msgs))
383 			break;
384 
385 		msgs[1].buf += this_len;
386 		dev_addr += this_len;
387 		len -= this_len;
388 	}
389 
390 	return msgs[1].buf - (u8 *)buf;
391 }
392 
393 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
394 	size_t len)
395 {
396 	struct i2c_msg msgs[1];
397 	u8 bus_addr = a2 ? 0x51 : 0x50;
398 	int ret;
399 
400 	msgs[0].addr = bus_addr;
401 	msgs[0].flags = 0;
402 	msgs[0].len = 1 + len;
403 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
404 	if (!msgs[0].buf)
405 		return -ENOMEM;
406 
407 	msgs[0].buf[0] = dev_addr;
408 	memcpy(&msgs[0].buf[1], buf, len);
409 
410 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
411 
412 	kfree(msgs[0].buf);
413 
414 	if (ret < 0)
415 		return ret;
416 
417 	return ret == ARRAY_SIZE(msgs) ? len : 0;
418 }
419 
420 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
421 {
422 	struct mii_bus *i2c_mii;
423 	int ret;
424 
425 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
426 		return -EINVAL;
427 
428 	sfp->i2c = i2c;
429 	sfp->read = sfp_i2c_read;
430 	sfp->write = sfp_i2c_write;
431 
432 	i2c_mii = mdio_i2c_alloc(sfp->dev, i2c);
433 	if (IS_ERR(i2c_mii))
434 		return PTR_ERR(i2c_mii);
435 
436 	i2c_mii->name = "SFP I2C Bus";
437 	i2c_mii->phy_mask = ~0;
438 
439 	ret = mdiobus_register(i2c_mii);
440 	if (ret < 0) {
441 		mdiobus_free(i2c_mii);
442 		return ret;
443 	}
444 
445 	sfp->i2c_mii = i2c_mii;
446 
447 	return 0;
448 }
449 
450 /* Interface */
451 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
452 {
453 	return sfp->read(sfp, a2, addr, buf, len);
454 }
455 
456 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
457 {
458 	return sfp->write(sfp, a2, addr, buf, len);
459 }
460 
461 static unsigned int sfp_soft_get_state(struct sfp *sfp)
462 {
463 	unsigned int state = 0;
464 	u8 status;
465 	int ret;
466 
467 	ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
468 	if (ret == sizeof(status)) {
469 		if (status & SFP_STATUS_RX_LOS)
470 			state |= SFP_F_LOS;
471 		if (status & SFP_STATUS_TX_FAULT)
472 			state |= SFP_F_TX_FAULT;
473 	} else {
474 		dev_err_ratelimited(sfp->dev,
475 				    "failed to read SFP soft status: %pe\n",
476 				    ERR_PTR(ret));
477 		/* Preserve the current state */
478 		state = sfp->state;
479 	}
480 
481 	return state & sfp->state_soft_mask;
482 }
483 
484 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state)
485 {
486 	u8 status;
487 
488 	if (sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status)) ==
489 		     sizeof(status)) {
490 		if (state & SFP_F_TX_DISABLE)
491 			status |= SFP_STATUS_TX_DISABLE_FORCE;
492 		else
493 			status &= ~SFP_STATUS_TX_DISABLE_FORCE;
494 
495 		sfp_write(sfp, true, SFP_STATUS, &status, sizeof(status));
496 	}
497 }
498 
499 static void sfp_soft_start_poll(struct sfp *sfp)
500 {
501 	const struct sfp_eeprom_id *id = &sfp->id;
502 
503 	sfp->state_soft_mask = 0;
504 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE &&
505 	    !sfp->gpio[GPIO_TX_DISABLE])
506 		sfp->state_soft_mask |= SFP_F_TX_DISABLE;
507 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT &&
508 	    !sfp->gpio[GPIO_TX_FAULT])
509 		sfp->state_soft_mask |= SFP_F_TX_FAULT;
510 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS &&
511 	    !sfp->gpio[GPIO_LOS])
512 		sfp->state_soft_mask |= SFP_F_LOS;
513 
514 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
515 	    !sfp->need_poll)
516 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
517 }
518 
519 static void sfp_soft_stop_poll(struct sfp *sfp)
520 {
521 	sfp->state_soft_mask = 0;
522 }
523 
524 static unsigned int sfp_get_state(struct sfp *sfp)
525 {
526 	unsigned int state = sfp->get_state(sfp);
527 
528 	if (state & SFP_F_PRESENT &&
529 	    sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT))
530 		state |= sfp_soft_get_state(sfp);
531 
532 	return state;
533 }
534 
535 static void sfp_set_state(struct sfp *sfp, unsigned int state)
536 {
537 	sfp->set_state(sfp, state);
538 
539 	if (state & SFP_F_PRESENT &&
540 	    sfp->state_soft_mask & SFP_F_TX_DISABLE)
541 		sfp_soft_set_state(sfp, state);
542 }
543 
544 static unsigned int sfp_check(void *buf, size_t len)
545 {
546 	u8 *p, check;
547 
548 	for (p = buf, check = 0; len; p++, len--)
549 		check += *p;
550 
551 	return check;
552 }
553 
554 /* hwmon */
555 #if IS_ENABLED(CONFIG_HWMON)
556 static umode_t sfp_hwmon_is_visible(const void *data,
557 				    enum hwmon_sensor_types type,
558 				    u32 attr, int channel)
559 {
560 	const struct sfp *sfp = data;
561 
562 	switch (type) {
563 	case hwmon_temp:
564 		switch (attr) {
565 		case hwmon_temp_min_alarm:
566 		case hwmon_temp_max_alarm:
567 		case hwmon_temp_lcrit_alarm:
568 		case hwmon_temp_crit_alarm:
569 		case hwmon_temp_min:
570 		case hwmon_temp_max:
571 		case hwmon_temp_lcrit:
572 		case hwmon_temp_crit:
573 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
574 				return 0;
575 			fallthrough;
576 		case hwmon_temp_input:
577 		case hwmon_temp_label:
578 			return 0444;
579 		default:
580 			return 0;
581 		}
582 	case hwmon_in:
583 		switch (attr) {
584 		case hwmon_in_min_alarm:
585 		case hwmon_in_max_alarm:
586 		case hwmon_in_lcrit_alarm:
587 		case hwmon_in_crit_alarm:
588 		case hwmon_in_min:
589 		case hwmon_in_max:
590 		case hwmon_in_lcrit:
591 		case hwmon_in_crit:
592 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
593 				return 0;
594 			fallthrough;
595 		case hwmon_in_input:
596 		case hwmon_in_label:
597 			return 0444;
598 		default:
599 			return 0;
600 		}
601 	case hwmon_curr:
602 		switch (attr) {
603 		case hwmon_curr_min_alarm:
604 		case hwmon_curr_max_alarm:
605 		case hwmon_curr_lcrit_alarm:
606 		case hwmon_curr_crit_alarm:
607 		case hwmon_curr_min:
608 		case hwmon_curr_max:
609 		case hwmon_curr_lcrit:
610 		case hwmon_curr_crit:
611 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
612 				return 0;
613 			fallthrough;
614 		case hwmon_curr_input:
615 		case hwmon_curr_label:
616 			return 0444;
617 		default:
618 			return 0;
619 		}
620 	case hwmon_power:
621 		/* External calibration of receive power requires
622 		 * floating point arithmetic. Doing that in the kernel
623 		 * is not easy, so just skip it. If the module does
624 		 * not require external calibration, we can however
625 		 * show receiver power, since FP is then not needed.
626 		 */
627 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
628 		    channel == 1)
629 			return 0;
630 		switch (attr) {
631 		case hwmon_power_min_alarm:
632 		case hwmon_power_max_alarm:
633 		case hwmon_power_lcrit_alarm:
634 		case hwmon_power_crit_alarm:
635 		case hwmon_power_min:
636 		case hwmon_power_max:
637 		case hwmon_power_lcrit:
638 		case hwmon_power_crit:
639 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
640 				return 0;
641 			fallthrough;
642 		case hwmon_power_input:
643 		case hwmon_power_label:
644 			return 0444;
645 		default:
646 			return 0;
647 		}
648 	default:
649 		return 0;
650 	}
651 }
652 
653 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
654 {
655 	__be16 val;
656 	int err;
657 
658 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
659 	if (err < 0)
660 		return err;
661 
662 	*value = be16_to_cpu(val);
663 
664 	return 0;
665 }
666 
667 static void sfp_hwmon_to_rx_power(long *value)
668 {
669 	*value = DIV_ROUND_CLOSEST(*value, 10);
670 }
671 
672 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
673 				long *value)
674 {
675 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
676 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
677 }
678 
679 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
680 {
681 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
682 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
683 
684 	if (*value >= 0x8000)
685 		*value -= 0x10000;
686 
687 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
688 }
689 
690 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
691 {
692 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
693 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
694 
695 	*value = DIV_ROUND_CLOSEST(*value, 10);
696 }
697 
698 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
699 {
700 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
701 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
702 
703 	*value = DIV_ROUND_CLOSEST(*value, 500);
704 }
705 
706 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
707 {
708 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
709 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
710 
711 	*value = DIV_ROUND_CLOSEST(*value, 10);
712 }
713 
714 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
715 {
716 	int err;
717 
718 	err = sfp_hwmon_read_sensor(sfp, reg, value);
719 	if (err < 0)
720 		return err;
721 
722 	sfp_hwmon_calibrate_temp(sfp, value);
723 
724 	return 0;
725 }
726 
727 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
728 {
729 	int err;
730 
731 	err = sfp_hwmon_read_sensor(sfp, reg, value);
732 	if (err < 0)
733 		return err;
734 
735 	sfp_hwmon_calibrate_vcc(sfp, value);
736 
737 	return 0;
738 }
739 
740 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
741 {
742 	int err;
743 
744 	err = sfp_hwmon_read_sensor(sfp, reg, value);
745 	if (err < 0)
746 		return err;
747 
748 	sfp_hwmon_calibrate_bias(sfp, value);
749 
750 	return 0;
751 }
752 
753 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
754 {
755 	int err;
756 
757 	err = sfp_hwmon_read_sensor(sfp, reg, value);
758 	if (err < 0)
759 		return err;
760 
761 	sfp_hwmon_calibrate_tx_power(sfp, value);
762 
763 	return 0;
764 }
765 
766 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
767 {
768 	int err;
769 
770 	err = sfp_hwmon_read_sensor(sfp, reg, value);
771 	if (err < 0)
772 		return err;
773 
774 	sfp_hwmon_to_rx_power(value);
775 
776 	return 0;
777 }
778 
779 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
780 {
781 	u8 status;
782 	int err;
783 
784 	switch (attr) {
785 	case hwmon_temp_input:
786 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
787 
788 	case hwmon_temp_lcrit:
789 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
790 		sfp_hwmon_calibrate_temp(sfp, value);
791 		return 0;
792 
793 	case hwmon_temp_min:
794 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
795 		sfp_hwmon_calibrate_temp(sfp, value);
796 		return 0;
797 	case hwmon_temp_max:
798 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
799 		sfp_hwmon_calibrate_temp(sfp, value);
800 		return 0;
801 
802 	case hwmon_temp_crit:
803 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
804 		sfp_hwmon_calibrate_temp(sfp, value);
805 		return 0;
806 
807 	case hwmon_temp_lcrit_alarm:
808 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
809 		if (err < 0)
810 			return err;
811 
812 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
813 		return 0;
814 
815 	case hwmon_temp_min_alarm:
816 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
817 		if (err < 0)
818 			return err;
819 
820 		*value = !!(status & SFP_WARN0_TEMP_LOW);
821 		return 0;
822 
823 	case hwmon_temp_max_alarm:
824 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
825 		if (err < 0)
826 			return err;
827 
828 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
829 		return 0;
830 
831 	case hwmon_temp_crit_alarm:
832 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
833 		if (err < 0)
834 			return err;
835 
836 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
837 		return 0;
838 	default:
839 		return -EOPNOTSUPP;
840 	}
841 
842 	return -EOPNOTSUPP;
843 }
844 
845 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
846 {
847 	u8 status;
848 	int err;
849 
850 	switch (attr) {
851 	case hwmon_in_input:
852 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
853 
854 	case hwmon_in_lcrit:
855 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
856 		sfp_hwmon_calibrate_vcc(sfp, value);
857 		return 0;
858 
859 	case hwmon_in_min:
860 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
861 		sfp_hwmon_calibrate_vcc(sfp, value);
862 		return 0;
863 
864 	case hwmon_in_max:
865 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
866 		sfp_hwmon_calibrate_vcc(sfp, value);
867 		return 0;
868 
869 	case hwmon_in_crit:
870 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
871 		sfp_hwmon_calibrate_vcc(sfp, value);
872 		return 0;
873 
874 	case hwmon_in_lcrit_alarm:
875 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
876 		if (err < 0)
877 			return err;
878 
879 		*value = !!(status & SFP_ALARM0_VCC_LOW);
880 		return 0;
881 
882 	case hwmon_in_min_alarm:
883 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
884 		if (err < 0)
885 			return err;
886 
887 		*value = !!(status & SFP_WARN0_VCC_LOW);
888 		return 0;
889 
890 	case hwmon_in_max_alarm:
891 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
892 		if (err < 0)
893 			return err;
894 
895 		*value = !!(status & SFP_WARN0_VCC_HIGH);
896 		return 0;
897 
898 	case hwmon_in_crit_alarm:
899 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
900 		if (err < 0)
901 			return err;
902 
903 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
904 		return 0;
905 	default:
906 		return -EOPNOTSUPP;
907 	}
908 
909 	return -EOPNOTSUPP;
910 }
911 
912 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
913 {
914 	u8 status;
915 	int err;
916 
917 	switch (attr) {
918 	case hwmon_curr_input:
919 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
920 
921 	case hwmon_curr_lcrit:
922 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
923 		sfp_hwmon_calibrate_bias(sfp, value);
924 		return 0;
925 
926 	case hwmon_curr_min:
927 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
928 		sfp_hwmon_calibrate_bias(sfp, value);
929 		return 0;
930 
931 	case hwmon_curr_max:
932 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
933 		sfp_hwmon_calibrate_bias(sfp, value);
934 		return 0;
935 
936 	case hwmon_curr_crit:
937 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
938 		sfp_hwmon_calibrate_bias(sfp, value);
939 		return 0;
940 
941 	case hwmon_curr_lcrit_alarm:
942 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
943 		if (err < 0)
944 			return err;
945 
946 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
947 		return 0;
948 
949 	case hwmon_curr_min_alarm:
950 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
951 		if (err < 0)
952 			return err;
953 
954 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
955 		return 0;
956 
957 	case hwmon_curr_max_alarm:
958 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
959 		if (err < 0)
960 			return err;
961 
962 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
963 		return 0;
964 
965 	case hwmon_curr_crit_alarm:
966 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
967 		if (err < 0)
968 			return err;
969 
970 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
971 		return 0;
972 	default:
973 		return -EOPNOTSUPP;
974 	}
975 
976 	return -EOPNOTSUPP;
977 }
978 
979 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
980 {
981 	u8 status;
982 	int err;
983 
984 	switch (attr) {
985 	case hwmon_power_input:
986 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
987 
988 	case hwmon_power_lcrit:
989 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
990 		sfp_hwmon_calibrate_tx_power(sfp, value);
991 		return 0;
992 
993 	case hwmon_power_min:
994 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
995 		sfp_hwmon_calibrate_tx_power(sfp, value);
996 		return 0;
997 
998 	case hwmon_power_max:
999 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
1000 		sfp_hwmon_calibrate_tx_power(sfp, value);
1001 		return 0;
1002 
1003 	case hwmon_power_crit:
1004 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
1005 		sfp_hwmon_calibrate_tx_power(sfp, value);
1006 		return 0;
1007 
1008 	case hwmon_power_lcrit_alarm:
1009 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1010 		if (err < 0)
1011 			return err;
1012 
1013 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
1014 		return 0;
1015 
1016 	case hwmon_power_min_alarm:
1017 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1018 		if (err < 0)
1019 			return err;
1020 
1021 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
1022 		return 0;
1023 
1024 	case hwmon_power_max_alarm:
1025 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1026 		if (err < 0)
1027 			return err;
1028 
1029 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1030 		return 0;
1031 
1032 	case hwmon_power_crit_alarm:
1033 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1034 		if (err < 0)
1035 			return err;
1036 
1037 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1038 		return 0;
1039 	default:
1040 		return -EOPNOTSUPP;
1041 	}
1042 
1043 	return -EOPNOTSUPP;
1044 }
1045 
1046 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1047 {
1048 	u8 status;
1049 	int err;
1050 
1051 	switch (attr) {
1052 	case hwmon_power_input:
1053 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1054 
1055 	case hwmon_power_lcrit:
1056 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1057 		sfp_hwmon_to_rx_power(value);
1058 		return 0;
1059 
1060 	case hwmon_power_min:
1061 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1062 		sfp_hwmon_to_rx_power(value);
1063 		return 0;
1064 
1065 	case hwmon_power_max:
1066 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1067 		sfp_hwmon_to_rx_power(value);
1068 		return 0;
1069 
1070 	case hwmon_power_crit:
1071 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1072 		sfp_hwmon_to_rx_power(value);
1073 		return 0;
1074 
1075 	case hwmon_power_lcrit_alarm:
1076 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1077 		if (err < 0)
1078 			return err;
1079 
1080 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1081 		return 0;
1082 
1083 	case hwmon_power_min_alarm:
1084 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1085 		if (err < 0)
1086 			return err;
1087 
1088 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1089 		return 0;
1090 
1091 	case hwmon_power_max_alarm:
1092 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1093 		if (err < 0)
1094 			return err;
1095 
1096 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1097 		return 0;
1098 
1099 	case hwmon_power_crit_alarm:
1100 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1101 		if (err < 0)
1102 			return err;
1103 
1104 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1105 		return 0;
1106 	default:
1107 		return -EOPNOTSUPP;
1108 	}
1109 
1110 	return -EOPNOTSUPP;
1111 }
1112 
1113 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1114 			  u32 attr, int channel, long *value)
1115 {
1116 	struct sfp *sfp = dev_get_drvdata(dev);
1117 
1118 	switch (type) {
1119 	case hwmon_temp:
1120 		return sfp_hwmon_temp(sfp, attr, value);
1121 	case hwmon_in:
1122 		return sfp_hwmon_vcc(sfp, attr, value);
1123 	case hwmon_curr:
1124 		return sfp_hwmon_bias(sfp, attr, value);
1125 	case hwmon_power:
1126 		switch (channel) {
1127 		case 0:
1128 			return sfp_hwmon_tx_power(sfp, attr, value);
1129 		case 1:
1130 			return sfp_hwmon_rx_power(sfp, attr, value);
1131 		default:
1132 			return -EOPNOTSUPP;
1133 		}
1134 	default:
1135 		return -EOPNOTSUPP;
1136 	}
1137 }
1138 
1139 static const char *const sfp_hwmon_power_labels[] = {
1140 	"TX_power",
1141 	"RX_power",
1142 };
1143 
1144 static int sfp_hwmon_read_string(struct device *dev,
1145 				 enum hwmon_sensor_types type,
1146 				 u32 attr, int channel, const char **str)
1147 {
1148 	switch (type) {
1149 	case hwmon_curr:
1150 		switch (attr) {
1151 		case hwmon_curr_label:
1152 			*str = "bias";
1153 			return 0;
1154 		default:
1155 			return -EOPNOTSUPP;
1156 		}
1157 		break;
1158 	case hwmon_temp:
1159 		switch (attr) {
1160 		case hwmon_temp_label:
1161 			*str = "temperature";
1162 			return 0;
1163 		default:
1164 			return -EOPNOTSUPP;
1165 		}
1166 		break;
1167 	case hwmon_in:
1168 		switch (attr) {
1169 		case hwmon_in_label:
1170 			*str = "VCC";
1171 			return 0;
1172 		default:
1173 			return -EOPNOTSUPP;
1174 		}
1175 		break;
1176 	case hwmon_power:
1177 		switch (attr) {
1178 		case hwmon_power_label:
1179 			*str = sfp_hwmon_power_labels[channel];
1180 			return 0;
1181 		default:
1182 			return -EOPNOTSUPP;
1183 		}
1184 		break;
1185 	default:
1186 		return -EOPNOTSUPP;
1187 	}
1188 
1189 	return -EOPNOTSUPP;
1190 }
1191 
1192 static const struct hwmon_ops sfp_hwmon_ops = {
1193 	.is_visible = sfp_hwmon_is_visible,
1194 	.read = sfp_hwmon_read,
1195 	.read_string = sfp_hwmon_read_string,
1196 };
1197 
1198 static u32 sfp_hwmon_chip_config[] = {
1199 	HWMON_C_REGISTER_TZ,
1200 	0,
1201 };
1202 
1203 static const struct hwmon_channel_info sfp_hwmon_chip = {
1204 	.type = hwmon_chip,
1205 	.config = sfp_hwmon_chip_config,
1206 };
1207 
1208 static u32 sfp_hwmon_temp_config[] = {
1209 	HWMON_T_INPUT |
1210 	HWMON_T_MAX | HWMON_T_MIN |
1211 	HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1212 	HWMON_T_CRIT | HWMON_T_LCRIT |
1213 	HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1214 	HWMON_T_LABEL,
1215 	0,
1216 };
1217 
1218 static const struct hwmon_channel_info sfp_hwmon_temp_channel_info = {
1219 	.type = hwmon_temp,
1220 	.config = sfp_hwmon_temp_config,
1221 };
1222 
1223 static u32 sfp_hwmon_vcc_config[] = {
1224 	HWMON_I_INPUT |
1225 	HWMON_I_MAX | HWMON_I_MIN |
1226 	HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1227 	HWMON_I_CRIT | HWMON_I_LCRIT |
1228 	HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1229 	HWMON_I_LABEL,
1230 	0,
1231 };
1232 
1233 static const struct hwmon_channel_info sfp_hwmon_vcc_channel_info = {
1234 	.type = hwmon_in,
1235 	.config = sfp_hwmon_vcc_config,
1236 };
1237 
1238 static u32 sfp_hwmon_bias_config[] = {
1239 	HWMON_C_INPUT |
1240 	HWMON_C_MAX | HWMON_C_MIN |
1241 	HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1242 	HWMON_C_CRIT | HWMON_C_LCRIT |
1243 	HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1244 	HWMON_C_LABEL,
1245 	0,
1246 };
1247 
1248 static const struct hwmon_channel_info sfp_hwmon_bias_channel_info = {
1249 	.type = hwmon_curr,
1250 	.config = sfp_hwmon_bias_config,
1251 };
1252 
1253 static u32 sfp_hwmon_power_config[] = {
1254 	/* Transmit power */
1255 	HWMON_P_INPUT |
1256 	HWMON_P_MAX | HWMON_P_MIN |
1257 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1258 	HWMON_P_CRIT | HWMON_P_LCRIT |
1259 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1260 	HWMON_P_LABEL,
1261 	/* Receive power */
1262 	HWMON_P_INPUT |
1263 	HWMON_P_MAX | HWMON_P_MIN |
1264 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1265 	HWMON_P_CRIT | HWMON_P_LCRIT |
1266 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1267 	HWMON_P_LABEL,
1268 	0,
1269 };
1270 
1271 static const struct hwmon_channel_info sfp_hwmon_power_channel_info = {
1272 	.type = hwmon_power,
1273 	.config = sfp_hwmon_power_config,
1274 };
1275 
1276 static const struct hwmon_channel_info *sfp_hwmon_info[] = {
1277 	&sfp_hwmon_chip,
1278 	&sfp_hwmon_vcc_channel_info,
1279 	&sfp_hwmon_temp_channel_info,
1280 	&sfp_hwmon_bias_channel_info,
1281 	&sfp_hwmon_power_channel_info,
1282 	NULL,
1283 };
1284 
1285 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1286 	.ops = &sfp_hwmon_ops,
1287 	.info = sfp_hwmon_info,
1288 };
1289 
1290 static void sfp_hwmon_probe(struct work_struct *work)
1291 {
1292 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1293 	int err, i;
1294 
1295 	/* hwmon interface needs to access 16bit registers in atomic way to
1296 	 * guarantee coherency of the diagnostic monitoring data. If it is not
1297 	 * possible to guarantee coherency because EEPROM is broken in such way
1298 	 * that does not support atomic 16bit read operation then we have to
1299 	 * skip registration of hwmon device.
1300 	 */
1301 	if (sfp->i2c_block_size < 2) {
1302 		dev_info(sfp->dev,
1303 			 "skipping hwmon device registration due to broken EEPROM\n");
1304 		dev_info(sfp->dev,
1305 			 "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
1306 		return;
1307 	}
1308 
1309 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1310 	if (err < 0) {
1311 		if (sfp->hwmon_tries--) {
1312 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1313 					 T_PROBE_RETRY_SLOW);
1314 		} else {
1315 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
1316 				 ERR_PTR(err));
1317 		}
1318 		return;
1319 	}
1320 
1321 	sfp->hwmon_name = kstrdup(dev_name(sfp->dev), GFP_KERNEL);
1322 	if (!sfp->hwmon_name) {
1323 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1324 		return;
1325 	}
1326 
1327 	for (i = 0; sfp->hwmon_name[i]; i++)
1328 		if (hwmon_is_bad_char(sfp->hwmon_name[i]))
1329 			sfp->hwmon_name[i] = '_';
1330 
1331 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1332 							 sfp->hwmon_name, sfp,
1333 							 &sfp_hwmon_chip_info,
1334 							 NULL);
1335 	if (IS_ERR(sfp->hwmon_dev))
1336 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1337 			PTR_ERR(sfp->hwmon_dev));
1338 }
1339 
1340 static int sfp_hwmon_insert(struct sfp *sfp)
1341 {
1342 	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
1343 		return 0;
1344 
1345 	if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
1346 		return 0;
1347 
1348 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1349 		/* This driver in general does not support address
1350 		 * change.
1351 		 */
1352 		return 0;
1353 
1354 	mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1355 	sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1356 
1357 	return 0;
1358 }
1359 
1360 static void sfp_hwmon_remove(struct sfp *sfp)
1361 {
1362 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1363 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1364 		hwmon_device_unregister(sfp->hwmon_dev);
1365 		sfp->hwmon_dev = NULL;
1366 		kfree(sfp->hwmon_name);
1367 	}
1368 }
1369 
1370 static int sfp_hwmon_init(struct sfp *sfp)
1371 {
1372 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1373 
1374 	return 0;
1375 }
1376 
1377 static void sfp_hwmon_exit(struct sfp *sfp)
1378 {
1379 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1380 }
1381 #else
1382 static int sfp_hwmon_insert(struct sfp *sfp)
1383 {
1384 	return 0;
1385 }
1386 
1387 static void sfp_hwmon_remove(struct sfp *sfp)
1388 {
1389 }
1390 
1391 static int sfp_hwmon_init(struct sfp *sfp)
1392 {
1393 	return 0;
1394 }
1395 
1396 static void sfp_hwmon_exit(struct sfp *sfp)
1397 {
1398 }
1399 #endif
1400 
1401 /* Helpers */
1402 static void sfp_module_tx_disable(struct sfp *sfp)
1403 {
1404 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1405 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1406 	sfp->state |= SFP_F_TX_DISABLE;
1407 	sfp_set_state(sfp, sfp->state);
1408 }
1409 
1410 static void sfp_module_tx_enable(struct sfp *sfp)
1411 {
1412 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1413 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1414 	sfp->state &= ~SFP_F_TX_DISABLE;
1415 	sfp_set_state(sfp, sfp->state);
1416 }
1417 
1418 #if IS_ENABLED(CONFIG_DEBUG_FS)
1419 static int sfp_debug_state_show(struct seq_file *s, void *data)
1420 {
1421 	struct sfp *sfp = s->private;
1422 
1423 	seq_printf(s, "Module state: %s\n",
1424 		   mod_state_to_str(sfp->sm_mod_state));
1425 	seq_printf(s, "Module probe attempts: %d %d\n",
1426 		   R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
1427 		   R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
1428 	seq_printf(s, "Device state: %s\n",
1429 		   dev_state_to_str(sfp->sm_dev_state));
1430 	seq_printf(s, "Main state: %s\n",
1431 		   sm_state_to_str(sfp->sm_state));
1432 	seq_printf(s, "Fault recovery remaining retries: %d\n",
1433 		   sfp->sm_fault_retries);
1434 	seq_printf(s, "PHY probe remaining retries: %d\n",
1435 		   sfp->sm_phy_retries);
1436 	seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
1437 	seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
1438 	seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
1439 	seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
1440 	return 0;
1441 }
1442 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
1443 
1444 static void sfp_debugfs_init(struct sfp *sfp)
1445 {
1446 	sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
1447 
1448 	debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
1449 			    &sfp_debug_state_fops);
1450 }
1451 
1452 static void sfp_debugfs_exit(struct sfp *sfp)
1453 {
1454 	debugfs_remove_recursive(sfp->debugfs_dir);
1455 }
1456 #else
1457 static void sfp_debugfs_init(struct sfp *sfp)
1458 {
1459 }
1460 
1461 static void sfp_debugfs_exit(struct sfp *sfp)
1462 {
1463 }
1464 #endif
1465 
1466 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1467 {
1468 	unsigned int state = sfp->state;
1469 
1470 	if (state & SFP_F_TX_DISABLE)
1471 		return;
1472 
1473 	sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1474 
1475 	udelay(T_RESET_US);
1476 
1477 	sfp_set_state(sfp, state);
1478 }
1479 
1480 /* SFP state machine */
1481 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1482 {
1483 	if (timeout)
1484 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1485 				 timeout);
1486 	else
1487 		cancel_delayed_work(&sfp->timeout);
1488 }
1489 
1490 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1491 			unsigned int timeout)
1492 {
1493 	sfp->sm_state = state;
1494 	sfp_sm_set_timer(sfp, timeout);
1495 }
1496 
1497 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1498 			    unsigned int timeout)
1499 {
1500 	sfp->sm_mod_state = state;
1501 	sfp_sm_set_timer(sfp, timeout);
1502 }
1503 
1504 static void sfp_sm_phy_detach(struct sfp *sfp)
1505 {
1506 	sfp_remove_phy(sfp->sfp_bus);
1507 	phy_device_remove(sfp->mod_phy);
1508 	phy_device_free(sfp->mod_phy);
1509 	sfp->mod_phy = NULL;
1510 }
1511 
1512 static int sfp_sm_probe_phy(struct sfp *sfp, bool is_c45)
1513 {
1514 	struct phy_device *phy;
1515 	int err;
1516 
1517 	phy = get_phy_device(sfp->i2c_mii, SFP_PHY_ADDR, is_c45);
1518 	if (phy == ERR_PTR(-ENODEV))
1519 		return PTR_ERR(phy);
1520 	if (IS_ERR(phy)) {
1521 		dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
1522 		return PTR_ERR(phy);
1523 	}
1524 
1525 	err = phy_device_register(phy);
1526 	if (err) {
1527 		phy_device_free(phy);
1528 		dev_err(sfp->dev, "phy_device_register failed: %pe\n",
1529 			ERR_PTR(err));
1530 		return err;
1531 	}
1532 
1533 	err = sfp_add_phy(sfp->sfp_bus, phy);
1534 	if (err) {
1535 		phy_device_remove(phy);
1536 		phy_device_free(phy);
1537 		dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
1538 		return err;
1539 	}
1540 
1541 	sfp->mod_phy = phy;
1542 
1543 	return 0;
1544 }
1545 
1546 static void sfp_sm_link_up(struct sfp *sfp)
1547 {
1548 	sfp_link_up(sfp->sfp_bus);
1549 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1550 }
1551 
1552 static void sfp_sm_link_down(struct sfp *sfp)
1553 {
1554 	sfp_link_down(sfp->sfp_bus);
1555 }
1556 
1557 static void sfp_sm_link_check_los(struct sfp *sfp)
1558 {
1559 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1560 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1561 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1562 	bool los = false;
1563 
1564 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1565 	 * are set, we assume that no LOS signal is available. If both are
1566 	 * set, we assume LOS is not implemented (and is meaningless.)
1567 	 */
1568 	if (los_options == los_inverted)
1569 		los = !(sfp->state & SFP_F_LOS);
1570 	else if (los_options == los_normal)
1571 		los = !!(sfp->state & SFP_F_LOS);
1572 
1573 	if (los)
1574 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1575 	else
1576 		sfp_sm_link_up(sfp);
1577 }
1578 
1579 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1580 {
1581 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1582 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1583 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1584 
1585 	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
1586 	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
1587 }
1588 
1589 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1590 {
1591 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1592 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1593 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1594 
1595 	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
1596 	       (los_options == los_normal && event == SFP_E_LOS_LOW);
1597 }
1598 
1599 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1600 {
1601 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
1602 		dev_err(sfp->dev,
1603 			"module persistently indicates fault, disabling\n");
1604 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1605 	} else {
1606 		if (warn)
1607 			dev_err(sfp->dev, "module transmit fault indicated\n");
1608 
1609 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1610 	}
1611 }
1612 
1613 /* Probe a SFP for a PHY device if the module supports copper - the PHY
1614  * normally sits at I2C bus address 0x56, and may either be a clause 22
1615  * or clause 45 PHY.
1616  *
1617  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
1618  * negotiation enabled, but some may be in 1000base-X - which is for the
1619  * PHY driver to determine.
1620  *
1621  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
1622  * mode according to the negotiated line speed.
1623  */
1624 static int sfp_sm_probe_for_phy(struct sfp *sfp)
1625 {
1626 	int err = 0;
1627 
1628 	switch (sfp->id.base.extended_cc) {
1629 	case SFF8024_ECC_10GBASE_T_SFI:
1630 	case SFF8024_ECC_10GBASE_T_SR:
1631 	case SFF8024_ECC_5GBASE_T:
1632 	case SFF8024_ECC_2_5GBASE_T:
1633 		err = sfp_sm_probe_phy(sfp, true);
1634 		break;
1635 
1636 	default:
1637 		if (sfp->id.base.e1000_base_t)
1638 			err = sfp_sm_probe_phy(sfp, false);
1639 		break;
1640 	}
1641 	return err;
1642 }
1643 
1644 static int sfp_module_parse_power(struct sfp *sfp)
1645 {
1646 	u32 power_mW = 1000;
1647 	bool supports_a2;
1648 
1649 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1650 		power_mW = 1500;
1651 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1652 		power_mW = 2000;
1653 
1654 	supports_a2 = sfp->id.ext.sff8472_compliance !=
1655 				SFP_SFF8472_COMPLIANCE_NONE ||
1656 		      sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
1657 
1658 	if (power_mW > sfp->max_power_mW) {
1659 		/* Module power specification exceeds the allowed maximum. */
1660 		if (!supports_a2) {
1661 			/* The module appears not to implement bus address
1662 			 * 0xa2, so assume that the module powers up in the
1663 			 * indicated mode.
1664 			 */
1665 			dev_err(sfp->dev,
1666 				"Host does not support %u.%uW modules\n",
1667 				power_mW / 1000, (power_mW / 100) % 10);
1668 			return -EINVAL;
1669 		} else {
1670 			dev_warn(sfp->dev,
1671 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1672 				 power_mW / 1000, (power_mW / 100) % 10);
1673 			return 0;
1674 		}
1675 	}
1676 
1677 	if (power_mW <= 1000) {
1678 		/* Modules below 1W do not require a power change sequence */
1679 		sfp->module_power_mW = power_mW;
1680 		return 0;
1681 	}
1682 
1683 	if (!supports_a2) {
1684 		/* The module power level is below the host maximum and the
1685 		 * module appears not to implement bus address 0xa2, so assume
1686 		 * that the module powers up in the indicated mode.
1687 		 */
1688 		return 0;
1689 	}
1690 
1691 	/* If the module requires a higher power mode, but also requires
1692 	 * an address change sequence, warn the user that the module may
1693 	 * not be functional.
1694 	 */
1695 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
1696 		dev_warn(sfp->dev,
1697 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1698 			 power_mW / 1000, (power_mW / 100) % 10);
1699 		return 0;
1700 	}
1701 
1702 	sfp->module_power_mW = power_mW;
1703 
1704 	return 0;
1705 }
1706 
1707 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1708 {
1709 	u8 val;
1710 	int err;
1711 
1712 	err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1713 	if (err != sizeof(val)) {
1714 		dev_err(sfp->dev, "Failed to read EEPROM: %pe\n", ERR_PTR(err));
1715 		return -EAGAIN;
1716 	}
1717 
1718 	/* DM7052 reports as a high power module, responds to reads (with
1719 	 * all bytes 0xff) at 0x51 but does not accept writes.  In any case,
1720 	 * if the bit is already set, we're already in high power mode.
1721 	 */
1722 	if (!!(val & BIT(0)) == enable)
1723 		return 0;
1724 
1725 	if (enable)
1726 		val |= BIT(0);
1727 	else
1728 		val &= ~BIT(0);
1729 
1730 	err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1731 	if (err != sizeof(val)) {
1732 		dev_err(sfp->dev, "Failed to write EEPROM: %pe\n",
1733 			ERR_PTR(err));
1734 		return -EAGAIN;
1735 	}
1736 
1737 	if (enable)
1738 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1739 			 sfp->module_power_mW / 1000,
1740 			 (sfp->module_power_mW / 100) % 10);
1741 
1742 	return 0;
1743 }
1744 
1745 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
1746  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
1747  * not support multibyte reads from the EEPROM. Each multi-byte read
1748  * operation returns just one byte of EEPROM followed by zeros. There is
1749  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
1750  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
1751  * name and vendor id into EEPROM, so there is even no way to detect if
1752  * module is V-SOL V2801F. Therefore check for those zeros in the read
1753  * data and then based on check switch to reading EEPROM to one byte
1754  * at a time.
1755  */
1756 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
1757 {
1758 	size_t i, block_size = sfp->i2c_block_size;
1759 
1760 	/* Already using byte IO */
1761 	if (block_size == 1)
1762 		return false;
1763 
1764 	for (i = 1; i < len; i += block_size) {
1765 		if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
1766 			return false;
1767 	}
1768 	return true;
1769 }
1770 
1771 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
1772 {
1773 	u8 check;
1774 	int err;
1775 
1776 	if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
1777 	    id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
1778 	    id->base.connector != SFF8024_CONNECTOR_LC) {
1779 		dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
1780 		id->base.phys_id = SFF8024_ID_SFF_8472;
1781 		id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
1782 		id->base.connector = SFF8024_CONNECTOR_LC;
1783 		err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
1784 		if (err != 3) {
1785 			dev_err(sfp->dev,
1786 				"Failed to rewrite module EEPROM: %pe\n",
1787 				ERR_PTR(err));
1788 			return err;
1789 		}
1790 
1791 		/* Cotsworks modules have been found to require a delay between write operations. */
1792 		mdelay(50);
1793 
1794 		/* Update base structure checksum */
1795 		check = sfp_check(&id->base, sizeof(id->base) - 1);
1796 		err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
1797 		if (err != 1) {
1798 			dev_err(sfp->dev,
1799 				"Failed to update base structure checksum in fiber module EEPROM: %pe\n",
1800 				ERR_PTR(err));
1801 			return err;
1802 		}
1803 	}
1804 	return 0;
1805 }
1806 
1807 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
1808 {
1809 	/* SFP module inserted - read I2C data */
1810 	struct sfp_eeprom_id id;
1811 	bool cotsworks_sfbg;
1812 	bool cotsworks;
1813 	u8 check;
1814 	int ret;
1815 
1816 	/* Some SFP modules and also some Linux I2C drivers do not like reads
1817 	 * longer than 16 bytes, so read the EEPROM in chunks of 16 bytes at
1818 	 * a time.
1819 	 */
1820 	sfp->i2c_block_size = 16;
1821 
1822 	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
1823 	if (ret < 0) {
1824 		if (report)
1825 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
1826 				ERR_PTR(ret));
1827 		return -EAGAIN;
1828 	}
1829 
1830 	if (ret != sizeof(id.base)) {
1831 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
1832 		return -EAGAIN;
1833 	}
1834 
1835 	/* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
1836 	 * address 0x51 is just one byte at a time. Also SFF-8472 requires
1837 	 * that EEPROM supports atomic 16bit read operation for diagnostic
1838 	 * fields, so do not switch to one byte reading at a time unless it
1839 	 * is really required and we have no other option.
1840 	 */
1841 	if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
1842 		dev_info(sfp->dev,
1843 			 "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
1844 		dev_info(sfp->dev,
1845 			 "Switching to reading EEPROM to one byte at a time\n");
1846 		sfp->i2c_block_size = 1;
1847 
1848 		ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
1849 		if (ret < 0) {
1850 			if (report)
1851 				dev_err(sfp->dev,
1852 					"failed to read EEPROM: %pe\n",
1853 					ERR_PTR(ret));
1854 			return -EAGAIN;
1855 		}
1856 
1857 		if (ret != sizeof(id.base)) {
1858 			dev_err(sfp->dev, "EEPROM short read: %pe\n",
1859 				ERR_PTR(ret));
1860 			return -EAGAIN;
1861 		}
1862 	}
1863 
1864 	/* Cotsworks do not seem to update the checksums when they
1865 	 * do the final programming with the final module part number,
1866 	 * serial number and date code.
1867 	 */
1868 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
1869 	cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
1870 
1871 	/* Cotsworks SFF module EEPROM do not always have valid phys_id,
1872 	 * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
1873 	 * Cotsworks PN matches and bytes are not correct.
1874 	 */
1875 	if (cotsworks && cotsworks_sfbg) {
1876 		ret = sfp_cotsworks_fixup_check(sfp, &id);
1877 		if (ret < 0)
1878 			return ret;
1879 	}
1880 
1881 	/* Validate the checksum over the base structure */
1882 	check = sfp_check(&id.base, sizeof(id.base) - 1);
1883 	if (check != id.base.cc_base) {
1884 		if (cotsworks) {
1885 			dev_warn(sfp->dev,
1886 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
1887 				 check, id.base.cc_base);
1888 		} else {
1889 			dev_err(sfp->dev,
1890 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
1891 				check, id.base.cc_base);
1892 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1893 				       16, 1, &id, sizeof(id), true);
1894 			return -EINVAL;
1895 		}
1896 	}
1897 
1898 	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
1899 	if (ret < 0) {
1900 		if (report)
1901 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
1902 				ERR_PTR(ret));
1903 		return -EAGAIN;
1904 	}
1905 
1906 	if (ret != sizeof(id.ext)) {
1907 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
1908 		return -EAGAIN;
1909 	}
1910 
1911 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
1912 	if (check != id.ext.cc_ext) {
1913 		if (cotsworks) {
1914 			dev_warn(sfp->dev,
1915 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
1916 				 check, id.ext.cc_ext);
1917 		} else {
1918 			dev_err(sfp->dev,
1919 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
1920 				check, id.ext.cc_ext);
1921 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1922 				       16, 1, &id, sizeof(id), true);
1923 			memset(&id.ext, 0, sizeof(id.ext));
1924 		}
1925 	}
1926 
1927 	sfp->id = id;
1928 
1929 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
1930 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
1931 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
1932 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
1933 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
1934 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
1935 
1936 	/* Check whether we support this module */
1937 	if (!sfp->type->module_supported(&id)) {
1938 		dev_err(sfp->dev,
1939 			"module is not supported - phys id 0x%02x 0x%02x\n",
1940 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
1941 		return -EINVAL;
1942 	}
1943 
1944 	/* If the module requires address swap mode, warn about it */
1945 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1946 		dev_warn(sfp->dev,
1947 			 "module address swap to access page 0xA2 is not supported.\n");
1948 
1949 	/* Parse the module power requirement */
1950 	ret = sfp_module_parse_power(sfp);
1951 	if (ret < 0)
1952 		return ret;
1953 
1954 	if (!memcmp(id.base.vendor_name, "ALCATELLUCENT   ", 16) &&
1955 	    !memcmp(id.base.vendor_pn, "3FE46541AA      ", 16))
1956 		sfp->module_t_start_up = T_START_UP_BAD_GPON;
1957 	else
1958 		sfp->module_t_start_up = T_START_UP;
1959 
1960 	if (!memcmp(id.base.vendor_name, "HUAWEI          ", 16) &&
1961 	    !memcmp(id.base.vendor_pn, "MA5671A         ", 16))
1962 		sfp->tx_fault_ignore = true;
1963 	else
1964 		sfp->tx_fault_ignore = false;
1965 
1966 	return 0;
1967 }
1968 
1969 static void sfp_sm_mod_remove(struct sfp *sfp)
1970 {
1971 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
1972 		sfp_module_remove(sfp->sfp_bus);
1973 
1974 	sfp_hwmon_remove(sfp);
1975 
1976 	memset(&sfp->id, 0, sizeof(sfp->id));
1977 	sfp->module_power_mW = 0;
1978 
1979 	dev_info(sfp->dev, "module removed\n");
1980 }
1981 
1982 /* This state machine tracks the upstream's state */
1983 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
1984 {
1985 	switch (sfp->sm_dev_state) {
1986 	default:
1987 		if (event == SFP_E_DEV_ATTACH)
1988 			sfp->sm_dev_state = SFP_DEV_DOWN;
1989 		break;
1990 
1991 	case SFP_DEV_DOWN:
1992 		if (event == SFP_E_DEV_DETACH)
1993 			sfp->sm_dev_state = SFP_DEV_DETACHED;
1994 		else if (event == SFP_E_DEV_UP)
1995 			sfp->sm_dev_state = SFP_DEV_UP;
1996 		break;
1997 
1998 	case SFP_DEV_UP:
1999 		if (event == SFP_E_DEV_DETACH)
2000 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2001 		else if (event == SFP_E_DEV_DOWN)
2002 			sfp->sm_dev_state = SFP_DEV_DOWN;
2003 		break;
2004 	}
2005 }
2006 
2007 /* This state machine tracks the insert/remove state of the module, probes
2008  * the on-board EEPROM, and sets up the power level.
2009  */
2010 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
2011 {
2012 	int err;
2013 
2014 	/* Handle remove event globally, it resets this state machine */
2015 	if (event == SFP_E_REMOVE) {
2016 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
2017 			sfp_sm_mod_remove(sfp);
2018 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
2019 		return;
2020 	}
2021 
2022 	/* Handle device detach globally */
2023 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
2024 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
2025 		if (sfp->module_power_mW > 1000 &&
2026 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
2027 			sfp_sm_mod_hpower(sfp, false);
2028 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2029 		return;
2030 	}
2031 
2032 	switch (sfp->sm_mod_state) {
2033 	default:
2034 		if (event == SFP_E_INSERT) {
2035 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
2036 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
2037 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
2038 		}
2039 		break;
2040 
2041 	case SFP_MOD_PROBE:
2042 		/* Wait for T_PROBE_INIT to time out */
2043 		if (event != SFP_E_TIMEOUT)
2044 			break;
2045 
2046 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
2047 		if (err == -EAGAIN) {
2048 			if (sfp->sm_mod_tries_init &&
2049 			   --sfp->sm_mod_tries_init) {
2050 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2051 				break;
2052 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
2053 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
2054 					dev_warn(sfp->dev,
2055 						 "please wait, module slow to respond\n");
2056 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
2057 				break;
2058 			}
2059 		}
2060 		if (err < 0) {
2061 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2062 			break;
2063 		}
2064 
2065 		err = sfp_hwmon_insert(sfp);
2066 		if (err)
2067 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
2068 				 ERR_PTR(err));
2069 
2070 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2071 		fallthrough;
2072 	case SFP_MOD_WAITDEV:
2073 		/* Ensure that the device is attached before proceeding */
2074 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
2075 			break;
2076 
2077 		/* Report the module insertion to the upstream device */
2078 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id);
2079 		if (err < 0) {
2080 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2081 			break;
2082 		}
2083 
2084 		/* If this is a power level 1 module, we are done */
2085 		if (sfp->module_power_mW <= 1000)
2086 			goto insert;
2087 
2088 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
2089 		fallthrough;
2090 	case SFP_MOD_HPOWER:
2091 		/* Enable high power mode */
2092 		err = sfp_sm_mod_hpower(sfp, true);
2093 		if (err < 0) {
2094 			if (err != -EAGAIN) {
2095 				sfp_module_remove(sfp->sfp_bus);
2096 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2097 			} else {
2098 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2099 			}
2100 			break;
2101 		}
2102 
2103 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
2104 		break;
2105 
2106 	case SFP_MOD_WAITPWR:
2107 		/* Wait for T_HPOWER_LEVEL to time out */
2108 		if (event != SFP_E_TIMEOUT)
2109 			break;
2110 
2111 	insert:
2112 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
2113 		break;
2114 
2115 	case SFP_MOD_PRESENT:
2116 	case SFP_MOD_ERROR:
2117 		break;
2118 	}
2119 }
2120 
2121 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
2122 {
2123 	unsigned long timeout;
2124 	int ret;
2125 
2126 	/* Some events are global */
2127 	if (sfp->sm_state != SFP_S_DOWN &&
2128 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2129 	     sfp->sm_dev_state != SFP_DEV_UP)) {
2130 		if (sfp->sm_state == SFP_S_LINK_UP &&
2131 		    sfp->sm_dev_state == SFP_DEV_UP)
2132 			sfp_sm_link_down(sfp);
2133 		if (sfp->sm_state > SFP_S_INIT)
2134 			sfp_module_stop(sfp->sfp_bus);
2135 		if (sfp->mod_phy)
2136 			sfp_sm_phy_detach(sfp);
2137 		sfp_module_tx_disable(sfp);
2138 		sfp_soft_stop_poll(sfp);
2139 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
2140 		return;
2141 	}
2142 
2143 	/* The main state machine */
2144 	switch (sfp->sm_state) {
2145 	case SFP_S_DOWN:
2146 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2147 		    sfp->sm_dev_state != SFP_DEV_UP)
2148 			break;
2149 
2150 		if (!(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE))
2151 			sfp_soft_start_poll(sfp);
2152 
2153 		sfp_module_tx_enable(sfp);
2154 
2155 		/* Initialise the fault clearance retries */
2156 		sfp->sm_fault_retries = N_FAULT_INIT;
2157 
2158 		/* We need to check the TX_FAULT state, which is not defined
2159 		 * while TX_DISABLE is asserted. The earliest we want to do
2160 		 * anything (such as probe for a PHY) is 50ms.
2161 		 */
2162 		sfp_sm_next(sfp, SFP_S_WAIT, T_WAIT);
2163 		break;
2164 
2165 	case SFP_S_WAIT:
2166 		if (event != SFP_E_TIMEOUT)
2167 			break;
2168 
2169 		if (sfp->state & SFP_F_TX_FAULT) {
2170 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
2171 			 * from the TX_DISABLE deassertion for the module to
2172 			 * initialise, which is indicated by TX_FAULT
2173 			 * deasserting.
2174 			 */
2175 			timeout = sfp->module_t_start_up;
2176 			if (timeout > T_WAIT)
2177 				timeout -= T_WAIT;
2178 			else
2179 				timeout = 1;
2180 
2181 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
2182 		} else {
2183 			/* TX_FAULT is not asserted, assume the module has
2184 			 * finished initialising.
2185 			 */
2186 			goto init_done;
2187 		}
2188 		break;
2189 
2190 	case SFP_S_INIT:
2191 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2192 			/* TX_FAULT is still asserted after t_init
2193 			 * or t_start_up, so assume there is a fault.
2194 			 */
2195 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
2196 				     sfp->sm_fault_retries == N_FAULT_INIT);
2197 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2198 	init_done:
2199 			sfp->sm_phy_retries = R_PHY_RETRY;
2200 			goto phy_probe;
2201 		}
2202 		break;
2203 
2204 	case SFP_S_INIT_PHY:
2205 		if (event != SFP_E_TIMEOUT)
2206 			break;
2207 	phy_probe:
2208 		/* TX_FAULT deasserted or we timed out with TX_FAULT
2209 		 * clear.  Probe for the PHY and check the LOS state.
2210 		 */
2211 		ret = sfp_sm_probe_for_phy(sfp);
2212 		if (ret == -ENODEV) {
2213 			if (--sfp->sm_phy_retries) {
2214 				sfp_sm_next(sfp, SFP_S_INIT_PHY, T_PHY_RETRY);
2215 				break;
2216 			} else {
2217 				dev_info(sfp->dev, "no PHY detected\n");
2218 			}
2219 		} else if (ret) {
2220 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2221 			break;
2222 		}
2223 		if (sfp_module_start(sfp->sfp_bus)) {
2224 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2225 			break;
2226 		}
2227 		sfp_sm_link_check_los(sfp);
2228 
2229 		/* Reset the fault retry count */
2230 		sfp->sm_fault_retries = N_FAULT;
2231 		break;
2232 
2233 	case SFP_S_INIT_TX_FAULT:
2234 		if (event == SFP_E_TIMEOUT) {
2235 			sfp_module_tx_fault_reset(sfp);
2236 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
2237 		}
2238 		break;
2239 
2240 	case SFP_S_WAIT_LOS:
2241 		if (event == SFP_E_TX_FAULT)
2242 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2243 		else if (sfp_los_event_inactive(sfp, event))
2244 			sfp_sm_link_up(sfp);
2245 		break;
2246 
2247 	case SFP_S_LINK_UP:
2248 		if (event == SFP_E_TX_FAULT) {
2249 			sfp_sm_link_down(sfp);
2250 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2251 		} else if (sfp_los_event_active(sfp, event)) {
2252 			sfp_sm_link_down(sfp);
2253 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2254 		}
2255 		break;
2256 
2257 	case SFP_S_TX_FAULT:
2258 		if (event == SFP_E_TIMEOUT) {
2259 			sfp_module_tx_fault_reset(sfp);
2260 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2261 		}
2262 		break;
2263 
2264 	case SFP_S_REINIT:
2265 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2266 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2267 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2268 			dev_info(sfp->dev, "module transmit fault recovered\n");
2269 			sfp_sm_link_check_los(sfp);
2270 		}
2271 		break;
2272 
2273 	case SFP_S_TX_DISABLE:
2274 		break;
2275 	}
2276 }
2277 
2278 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
2279 {
2280 	mutex_lock(&sfp->sm_mutex);
2281 
2282 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
2283 		mod_state_to_str(sfp->sm_mod_state),
2284 		dev_state_to_str(sfp->sm_dev_state),
2285 		sm_state_to_str(sfp->sm_state),
2286 		event_to_str(event));
2287 
2288 	sfp_sm_device(sfp, event);
2289 	sfp_sm_module(sfp, event);
2290 	sfp_sm_main(sfp, event);
2291 
2292 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
2293 		mod_state_to_str(sfp->sm_mod_state),
2294 		dev_state_to_str(sfp->sm_dev_state),
2295 		sm_state_to_str(sfp->sm_state));
2296 
2297 	mutex_unlock(&sfp->sm_mutex);
2298 }
2299 
2300 static void sfp_attach(struct sfp *sfp)
2301 {
2302 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
2303 }
2304 
2305 static void sfp_detach(struct sfp *sfp)
2306 {
2307 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
2308 }
2309 
2310 static void sfp_start(struct sfp *sfp)
2311 {
2312 	sfp_sm_event(sfp, SFP_E_DEV_UP);
2313 }
2314 
2315 static void sfp_stop(struct sfp *sfp)
2316 {
2317 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
2318 }
2319 
2320 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2321 {
2322 	/* locking... and check module is present */
2323 
2324 	if (sfp->id.ext.sff8472_compliance &&
2325 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2326 		modinfo->type = ETH_MODULE_SFF_8472;
2327 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2328 	} else {
2329 		modinfo->type = ETH_MODULE_SFF_8079;
2330 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2331 	}
2332 	return 0;
2333 }
2334 
2335 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2336 			     u8 *data)
2337 {
2338 	unsigned int first, last, len;
2339 	int ret;
2340 
2341 	if (ee->len == 0)
2342 		return -EINVAL;
2343 
2344 	first = ee->offset;
2345 	last = ee->offset + ee->len;
2346 	if (first < ETH_MODULE_SFF_8079_LEN) {
2347 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2348 		len -= first;
2349 
2350 		ret = sfp_read(sfp, false, first, data, len);
2351 		if (ret < 0)
2352 			return ret;
2353 
2354 		first += len;
2355 		data += len;
2356 	}
2357 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2358 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2359 		len -= first;
2360 		first -= ETH_MODULE_SFF_8079_LEN;
2361 
2362 		ret = sfp_read(sfp, true, first, data, len);
2363 		if (ret < 0)
2364 			return ret;
2365 	}
2366 	return 0;
2367 }
2368 
2369 static int sfp_module_eeprom_by_page(struct sfp *sfp,
2370 				     const struct ethtool_module_eeprom *page,
2371 				     struct netlink_ext_ack *extack)
2372 {
2373 	if (page->bank) {
2374 		NL_SET_ERR_MSG(extack, "Banks not supported");
2375 		return -EOPNOTSUPP;
2376 	}
2377 
2378 	if (page->page) {
2379 		NL_SET_ERR_MSG(extack, "Only page 0 supported");
2380 		return -EOPNOTSUPP;
2381 	}
2382 
2383 	if (page->i2c_address != 0x50 &&
2384 	    page->i2c_address != 0x51) {
2385 		NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
2386 		return -EOPNOTSUPP;
2387 	}
2388 
2389 	return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
2390 			page->data, page->length);
2391 };
2392 
2393 static const struct sfp_socket_ops sfp_module_ops = {
2394 	.attach = sfp_attach,
2395 	.detach = sfp_detach,
2396 	.start = sfp_start,
2397 	.stop = sfp_stop,
2398 	.module_info = sfp_module_info,
2399 	.module_eeprom = sfp_module_eeprom,
2400 	.module_eeprom_by_page = sfp_module_eeprom_by_page,
2401 };
2402 
2403 static void sfp_timeout(struct work_struct *work)
2404 {
2405 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2406 
2407 	rtnl_lock();
2408 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2409 	rtnl_unlock();
2410 }
2411 
2412 static void sfp_check_state(struct sfp *sfp)
2413 {
2414 	unsigned int state, i, changed;
2415 
2416 	mutex_lock(&sfp->st_mutex);
2417 	state = sfp_get_state(sfp);
2418 	changed = state ^ sfp->state;
2419 	if (sfp->tx_fault_ignore)
2420 		changed &= SFP_F_PRESENT | SFP_F_LOS;
2421 	else
2422 		changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2423 
2424 	for (i = 0; i < GPIO_MAX; i++)
2425 		if (changed & BIT(i))
2426 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_of_names[i],
2427 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2428 
2429 	state |= sfp->state & (SFP_F_TX_DISABLE | SFP_F_RATE_SELECT);
2430 	sfp->state = state;
2431 
2432 	rtnl_lock();
2433 	if (changed & SFP_F_PRESENT)
2434 		sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2435 				SFP_E_INSERT : SFP_E_REMOVE);
2436 
2437 	if (changed & SFP_F_TX_FAULT)
2438 		sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2439 				SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2440 
2441 	if (changed & SFP_F_LOS)
2442 		sfp_sm_event(sfp, state & SFP_F_LOS ?
2443 				SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2444 	rtnl_unlock();
2445 	mutex_unlock(&sfp->st_mutex);
2446 }
2447 
2448 static irqreturn_t sfp_irq(int irq, void *data)
2449 {
2450 	struct sfp *sfp = data;
2451 
2452 	sfp_check_state(sfp);
2453 
2454 	return IRQ_HANDLED;
2455 }
2456 
2457 static void sfp_poll(struct work_struct *work)
2458 {
2459 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2460 
2461 	sfp_check_state(sfp);
2462 
2463 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2464 	    sfp->need_poll)
2465 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2466 }
2467 
2468 static struct sfp *sfp_alloc(struct device *dev)
2469 {
2470 	struct sfp *sfp;
2471 
2472 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2473 	if (!sfp)
2474 		return ERR_PTR(-ENOMEM);
2475 
2476 	sfp->dev = dev;
2477 
2478 	mutex_init(&sfp->sm_mutex);
2479 	mutex_init(&sfp->st_mutex);
2480 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2481 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2482 
2483 	sfp_hwmon_init(sfp);
2484 
2485 	return sfp;
2486 }
2487 
2488 static void sfp_cleanup(void *data)
2489 {
2490 	struct sfp *sfp = data;
2491 
2492 	sfp_hwmon_exit(sfp);
2493 
2494 	cancel_delayed_work_sync(&sfp->poll);
2495 	cancel_delayed_work_sync(&sfp->timeout);
2496 	if (sfp->i2c_mii) {
2497 		mdiobus_unregister(sfp->i2c_mii);
2498 		mdiobus_free(sfp->i2c_mii);
2499 	}
2500 	if (sfp->i2c)
2501 		i2c_put_adapter(sfp->i2c);
2502 	kfree(sfp);
2503 }
2504 
2505 static int sfp_probe(struct platform_device *pdev)
2506 {
2507 	const struct sff_data *sff;
2508 	struct i2c_adapter *i2c;
2509 	char *sfp_irq_name;
2510 	struct sfp *sfp;
2511 	int err, i;
2512 
2513 	sfp = sfp_alloc(&pdev->dev);
2514 	if (IS_ERR(sfp))
2515 		return PTR_ERR(sfp);
2516 
2517 	platform_set_drvdata(pdev, sfp);
2518 
2519 	err = devm_add_action(sfp->dev, sfp_cleanup, sfp);
2520 	if (err < 0)
2521 		return err;
2522 
2523 	sff = sfp->type = &sfp_data;
2524 
2525 	if (pdev->dev.of_node) {
2526 		struct device_node *node = pdev->dev.of_node;
2527 		const struct of_device_id *id;
2528 		struct device_node *np;
2529 
2530 		id = of_match_node(sfp_of_match, node);
2531 		if (WARN_ON(!id))
2532 			return -EINVAL;
2533 
2534 		sff = sfp->type = id->data;
2535 
2536 		np = of_parse_phandle(node, "i2c-bus", 0);
2537 		if (!np) {
2538 			dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2539 			return -ENODEV;
2540 		}
2541 
2542 		i2c = of_find_i2c_adapter_by_node(np);
2543 		of_node_put(np);
2544 	} else if (has_acpi_companion(&pdev->dev)) {
2545 		struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
2546 		struct fwnode_handle *fw = acpi_fwnode_handle(adev);
2547 		struct fwnode_reference_args args;
2548 		struct acpi_handle *acpi_handle;
2549 		int ret;
2550 
2551 		ret = acpi_node_get_property_reference(fw, "i2c-bus", 0, &args);
2552 		if (ret || !is_acpi_device_node(args.fwnode)) {
2553 			dev_err(&pdev->dev, "missing 'i2c-bus' property\n");
2554 			return -ENODEV;
2555 		}
2556 
2557 		acpi_handle = ACPI_HANDLE_FWNODE(args.fwnode);
2558 		i2c = i2c_acpi_find_adapter_by_handle(acpi_handle);
2559 	} else {
2560 		return -EINVAL;
2561 	}
2562 
2563 	if (!i2c)
2564 		return -EPROBE_DEFER;
2565 
2566 	err = sfp_i2c_configure(sfp, i2c);
2567 	if (err < 0) {
2568 		i2c_put_adapter(i2c);
2569 		return err;
2570 	}
2571 
2572 	for (i = 0; i < GPIO_MAX; i++)
2573 		if (sff->gpios & BIT(i)) {
2574 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
2575 					   gpio_of_names[i], gpio_flags[i]);
2576 			if (IS_ERR(sfp->gpio[i]))
2577 				return PTR_ERR(sfp->gpio[i]);
2578 		}
2579 
2580 	sfp->get_state = sfp_gpio_get_state;
2581 	sfp->set_state = sfp_gpio_set_state;
2582 
2583 	/* Modules that have no detect signal are always present */
2584 	if (!(sfp->gpio[GPIO_MODDEF0]))
2585 		sfp->get_state = sff_gpio_get_state;
2586 
2587 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
2588 				 &sfp->max_power_mW);
2589 	if (!sfp->max_power_mW)
2590 		sfp->max_power_mW = 1000;
2591 
2592 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
2593 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
2594 
2595 	/* Get the initial state, and always signal TX disable,
2596 	 * since the network interface will not be up.
2597 	 */
2598 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
2599 
2600 	if (sfp->gpio[GPIO_RATE_SELECT] &&
2601 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RATE_SELECT]))
2602 		sfp->state |= SFP_F_RATE_SELECT;
2603 	sfp_set_state(sfp, sfp->state);
2604 	sfp_module_tx_disable(sfp);
2605 	if (sfp->state & SFP_F_PRESENT) {
2606 		rtnl_lock();
2607 		sfp_sm_event(sfp, SFP_E_INSERT);
2608 		rtnl_unlock();
2609 	}
2610 
2611 	for (i = 0; i < GPIO_MAX; i++) {
2612 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
2613 			continue;
2614 
2615 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
2616 		if (sfp->gpio_irq[i] < 0) {
2617 			sfp->gpio_irq[i] = 0;
2618 			sfp->need_poll = true;
2619 			continue;
2620 		}
2621 
2622 		sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
2623 					      "%s-%s", dev_name(sfp->dev),
2624 					      gpio_of_names[i]);
2625 
2626 		if (!sfp_irq_name)
2627 			return -ENOMEM;
2628 
2629 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
2630 						NULL, sfp_irq,
2631 						IRQF_ONESHOT |
2632 						IRQF_TRIGGER_RISING |
2633 						IRQF_TRIGGER_FALLING,
2634 						sfp_irq_name, sfp);
2635 		if (err) {
2636 			sfp->gpio_irq[i] = 0;
2637 			sfp->need_poll = true;
2638 		}
2639 	}
2640 
2641 	if (sfp->need_poll)
2642 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2643 
2644 	/* We could have an issue in cases no Tx disable pin is available or
2645 	 * wired as modules using a laser as their light source will continue to
2646 	 * be active when the fiber is removed. This could be a safety issue and
2647 	 * we should at least warn the user about that.
2648 	 */
2649 	if (!sfp->gpio[GPIO_TX_DISABLE])
2650 		dev_warn(sfp->dev,
2651 			 "No tx_disable pin: SFP modules will always be emitting.\n");
2652 
2653 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
2654 	if (!sfp->sfp_bus)
2655 		return -ENOMEM;
2656 
2657 	sfp_debugfs_init(sfp);
2658 
2659 	return 0;
2660 }
2661 
2662 static int sfp_remove(struct platform_device *pdev)
2663 {
2664 	struct sfp *sfp = platform_get_drvdata(pdev);
2665 
2666 	sfp_debugfs_exit(sfp);
2667 	sfp_unregister_socket(sfp->sfp_bus);
2668 
2669 	rtnl_lock();
2670 	sfp_sm_event(sfp, SFP_E_REMOVE);
2671 	rtnl_unlock();
2672 
2673 	return 0;
2674 }
2675 
2676 static void sfp_shutdown(struct platform_device *pdev)
2677 {
2678 	struct sfp *sfp = platform_get_drvdata(pdev);
2679 	int i;
2680 
2681 	for (i = 0; i < GPIO_MAX; i++) {
2682 		if (!sfp->gpio_irq[i])
2683 			continue;
2684 
2685 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
2686 	}
2687 
2688 	cancel_delayed_work_sync(&sfp->poll);
2689 	cancel_delayed_work_sync(&sfp->timeout);
2690 }
2691 
2692 static struct platform_driver sfp_driver = {
2693 	.probe = sfp_probe,
2694 	.remove = sfp_remove,
2695 	.shutdown = sfp_shutdown,
2696 	.driver = {
2697 		.name = "sfp",
2698 		.of_match_table = sfp_of_match,
2699 	},
2700 };
2701 
2702 static int sfp_init(void)
2703 {
2704 	poll_jiffies = msecs_to_jiffies(100);
2705 
2706 	return platform_driver_register(&sfp_driver);
2707 }
2708 module_init(sfp_init);
2709 
2710 static void sfp_exit(void)
2711 {
2712 	platform_driver_unregister(&sfp_driver);
2713 }
2714 module_exit(sfp_exit);
2715 
2716 MODULE_ALIAS("platform:sfp");
2717 MODULE_AUTHOR("Russell King");
2718 MODULE_LICENSE("GPL v2");
2719