xref: /linux/drivers/net/phy/sfp.c (revision a7d22ca2a483d6c69c0791954447464297315ffa)
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_WAIT,
63 	SFP_S_INIT,
64 	SFP_S_INIT_TX_FAULT,
65 	SFP_S_WAIT_LOS,
66 	SFP_S_LINK_UP,
67 	SFP_S_TX_FAULT,
68 	SFP_S_REINIT,
69 	SFP_S_TX_DISABLE,
70 };
71 
72 static const char  * const mod_state_strings[] = {
73 	[SFP_MOD_EMPTY] = "empty",
74 	[SFP_MOD_ERROR] = "error",
75 	[SFP_MOD_PROBE] = "probe",
76 	[SFP_MOD_WAITDEV] = "waitdev",
77 	[SFP_MOD_HPOWER] = "hpower",
78 	[SFP_MOD_WAITPWR] = "waitpwr",
79 	[SFP_MOD_PRESENT] = "present",
80 };
81 
82 static const char *mod_state_to_str(unsigned short mod_state)
83 {
84 	if (mod_state >= ARRAY_SIZE(mod_state_strings))
85 		return "Unknown module state";
86 	return mod_state_strings[mod_state];
87 }
88 
89 static const char * const dev_state_strings[] = {
90 	[SFP_DEV_DETACHED] = "detached",
91 	[SFP_DEV_DOWN] = "down",
92 	[SFP_DEV_UP] = "up",
93 };
94 
95 static const char *dev_state_to_str(unsigned short dev_state)
96 {
97 	if (dev_state >= ARRAY_SIZE(dev_state_strings))
98 		return "Unknown device state";
99 	return dev_state_strings[dev_state];
100 }
101 
102 static const char * const event_strings[] = {
103 	[SFP_E_INSERT] = "insert",
104 	[SFP_E_REMOVE] = "remove",
105 	[SFP_E_DEV_ATTACH] = "dev_attach",
106 	[SFP_E_DEV_DETACH] = "dev_detach",
107 	[SFP_E_DEV_DOWN] = "dev_down",
108 	[SFP_E_DEV_UP] = "dev_up",
109 	[SFP_E_TX_FAULT] = "tx_fault",
110 	[SFP_E_TX_CLEAR] = "tx_clear",
111 	[SFP_E_LOS_HIGH] = "los_high",
112 	[SFP_E_LOS_LOW] = "los_low",
113 	[SFP_E_TIMEOUT] = "timeout",
114 };
115 
116 static const char *event_to_str(unsigned short event)
117 {
118 	if (event >= ARRAY_SIZE(event_strings))
119 		return "Unknown event";
120 	return event_strings[event];
121 }
122 
123 static const char * const sm_state_strings[] = {
124 	[SFP_S_DOWN] = "down",
125 	[SFP_S_WAIT] = "wait",
126 	[SFP_S_INIT] = "init",
127 	[SFP_S_INIT_TX_FAULT] = "init_tx_fault",
128 	[SFP_S_WAIT_LOS] = "wait_los",
129 	[SFP_S_LINK_UP] = "link_up",
130 	[SFP_S_TX_FAULT] = "tx_fault",
131 	[SFP_S_REINIT] = "reinit",
132 	[SFP_S_TX_DISABLE] = "rx_disable",
133 };
134 
135 static const char *sm_state_to_str(unsigned short sm_state)
136 {
137 	if (sm_state >= ARRAY_SIZE(sm_state_strings))
138 		return "Unknown state";
139 	return sm_state_strings[sm_state];
140 }
141 
142 static const char *gpio_of_names[] = {
143 	"mod-def0",
144 	"los",
145 	"tx-fault",
146 	"tx-disable",
147 	"rate-select0",
148 };
149 
150 static const enum gpiod_flags gpio_flags[] = {
151 	GPIOD_IN,
152 	GPIOD_IN,
153 	GPIOD_IN,
154 	GPIOD_ASIS,
155 	GPIOD_ASIS,
156 };
157 
158 /* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
159  * non-cooled module to initialise its laser safety circuitry. We wait
160  * an initial T_WAIT period before we check the tx fault to give any PHY
161  * on board (for a copper SFP) time to initialise.
162  */
163 #define T_WAIT			msecs_to_jiffies(50)
164 #define T_START_UP		msecs_to_jiffies(300)
165 #define T_START_UP_BAD_GPON	msecs_to_jiffies(60000)
166 
167 /* t_reset is the time required to assert the TX_DISABLE signal to reset
168  * an indicated TX_FAULT.
169  */
170 #define T_RESET_US		10
171 #define T_FAULT_RECOVER		msecs_to_jiffies(1000)
172 
173 /* SFP module presence detection is poor: the three MOD DEF signals are
174  * the same length on the PCB, which means it's possible for MOD DEF 0 to
175  * connect before the I2C bus on MOD DEF 1/2.
176  *
177  * The SFF-8472 specifies t_serial ("Time from power on until module is
178  * ready for data transmission over the two wire serial bus.") as 300ms.
179  */
180 #define T_SERIAL		msecs_to_jiffies(300)
181 #define T_HPOWER_LEVEL		msecs_to_jiffies(300)
182 #define T_PROBE_RETRY_INIT	msecs_to_jiffies(100)
183 #define R_PROBE_RETRY_INIT	10
184 #define T_PROBE_RETRY_SLOW	msecs_to_jiffies(5000)
185 #define R_PROBE_RETRY_SLOW	12
186 
187 /* SFP modules appear to always have their PHY configured for bus address
188  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
189  */
190 #define SFP_PHY_ADDR	22
191 
192 struct sff_data {
193 	unsigned int gpios;
194 	bool (*module_supported)(const struct sfp_eeprom_id *id);
195 };
196 
197 struct sfp {
198 	struct device *dev;
199 	struct i2c_adapter *i2c;
200 	struct mii_bus *i2c_mii;
201 	struct sfp_bus *sfp_bus;
202 	struct phy_device *mod_phy;
203 	const struct sff_data *type;
204 	u32 max_power_mW;
205 
206 	unsigned int (*get_state)(struct sfp *);
207 	void (*set_state)(struct sfp *, unsigned int);
208 	int (*read)(struct sfp *, bool, u8, void *, size_t);
209 	int (*write)(struct sfp *, bool, u8, void *, size_t);
210 
211 	struct gpio_desc *gpio[GPIO_MAX];
212 	int gpio_irq[GPIO_MAX];
213 
214 	bool need_poll;
215 
216 	struct mutex st_mutex;			/* Protects state */
217 	unsigned int state_soft_mask;
218 	unsigned int state;
219 	struct delayed_work poll;
220 	struct delayed_work timeout;
221 	struct mutex sm_mutex;			/* Protects state machine */
222 	unsigned char sm_mod_state;
223 	unsigned char sm_mod_tries_init;
224 	unsigned char sm_mod_tries;
225 	unsigned char sm_dev_state;
226 	unsigned short sm_state;
227 	unsigned int sm_retries;
228 
229 	struct sfp_eeprom_id id;
230 	unsigned int module_power_mW;
231 	unsigned int module_t_start_up;
232 
233 #if IS_ENABLED(CONFIG_HWMON)
234 	struct sfp_diag diag;
235 	struct delayed_work hwmon_probe;
236 	unsigned int hwmon_tries;
237 	struct device *hwmon_dev;
238 	char *hwmon_name;
239 #endif
240 
241 };
242 
243 static bool sff_module_supported(const struct sfp_eeprom_id *id)
244 {
245 	return id->base.phys_id == SFP_PHYS_ID_SFF &&
246 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
247 }
248 
249 static const struct sff_data sff_data = {
250 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
251 	.module_supported = sff_module_supported,
252 };
253 
254 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
255 {
256 	return id->base.phys_id == SFP_PHYS_ID_SFP &&
257 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
258 }
259 
260 static const struct sff_data sfp_data = {
261 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
262 		 SFP_F_TX_DISABLE | SFP_F_RATE_SELECT,
263 	.module_supported = sfp_module_supported,
264 };
265 
266 static const struct of_device_id sfp_of_match[] = {
267 	{ .compatible = "sff,sff", .data = &sff_data, },
268 	{ .compatible = "sff,sfp", .data = &sfp_data, },
269 	{ },
270 };
271 MODULE_DEVICE_TABLE(of, sfp_of_match);
272 
273 static unsigned long poll_jiffies;
274 
275 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
276 {
277 	unsigned int i, state, v;
278 
279 	for (i = state = 0; i < GPIO_MAX; i++) {
280 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
281 			continue;
282 
283 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
284 		if (v)
285 			state |= BIT(i);
286 	}
287 
288 	return state;
289 }
290 
291 static unsigned int sff_gpio_get_state(struct sfp *sfp)
292 {
293 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
294 }
295 
296 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
297 {
298 	if (state & SFP_F_PRESENT) {
299 		/* If the module is present, drive the signals */
300 		if (sfp->gpio[GPIO_TX_DISABLE])
301 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
302 					       state & SFP_F_TX_DISABLE);
303 		if (state & SFP_F_RATE_SELECT)
304 			gpiod_direction_output(sfp->gpio[GPIO_RATE_SELECT],
305 					       state & SFP_F_RATE_SELECT);
306 	} else {
307 		/* Otherwise, let them float to the pull-ups */
308 		if (sfp->gpio[GPIO_TX_DISABLE])
309 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
310 		if (state & SFP_F_RATE_SELECT)
311 			gpiod_direction_input(sfp->gpio[GPIO_RATE_SELECT]);
312 	}
313 }
314 
315 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
316 			size_t len)
317 {
318 	struct i2c_msg msgs[2];
319 	u8 bus_addr = a2 ? 0x51 : 0x50;
320 	size_t this_len;
321 	int ret;
322 
323 	msgs[0].addr = bus_addr;
324 	msgs[0].flags = 0;
325 	msgs[0].len = 1;
326 	msgs[0].buf = &dev_addr;
327 	msgs[1].addr = bus_addr;
328 	msgs[1].flags = I2C_M_RD;
329 	msgs[1].len = len;
330 	msgs[1].buf = buf;
331 
332 	while (len) {
333 		this_len = len;
334 		if (this_len > 16)
335 			this_len = 16;
336 
337 		msgs[1].len = this_len;
338 
339 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
340 		if (ret < 0)
341 			return ret;
342 
343 		if (ret != ARRAY_SIZE(msgs))
344 			break;
345 
346 		msgs[1].buf += this_len;
347 		dev_addr += this_len;
348 		len -= this_len;
349 	}
350 
351 	return msgs[1].buf - (u8 *)buf;
352 }
353 
354 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
355 	size_t len)
356 {
357 	struct i2c_msg msgs[1];
358 	u8 bus_addr = a2 ? 0x51 : 0x50;
359 	int ret;
360 
361 	msgs[0].addr = bus_addr;
362 	msgs[0].flags = 0;
363 	msgs[0].len = 1 + len;
364 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
365 	if (!msgs[0].buf)
366 		return -ENOMEM;
367 
368 	msgs[0].buf[0] = dev_addr;
369 	memcpy(&msgs[0].buf[1], buf, len);
370 
371 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
372 
373 	kfree(msgs[0].buf);
374 
375 	if (ret < 0)
376 		return ret;
377 
378 	return ret == ARRAY_SIZE(msgs) ? len : 0;
379 }
380 
381 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
382 {
383 	struct mii_bus *i2c_mii;
384 	int ret;
385 
386 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
387 		return -EINVAL;
388 
389 	sfp->i2c = i2c;
390 	sfp->read = sfp_i2c_read;
391 	sfp->write = sfp_i2c_write;
392 
393 	i2c_mii = mdio_i2c_alloc(sfp->dev, i2c);
394 	if (IS_ERR(i2c_mii))
395 		return PTR_ERR(i2c_mii);
396 
397 	i2c_mii->name = "SFP I2C Bus";
398 	i2c_mii->phy_mask = ~0;
399 
400 	ret = mdiobus_register(i2c_mii);
401 	if (ret < 0) {
402 		mdiobus_free(i2c_mii);
403 		return ret;
404 	}
405 
406 	sfp->i2c_mii = i2c_mii;
407 
408 	return 0;
409 }
410 
411 /* Interface */
412 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
413 {
414 	return sfp->read(sfp, a2, addr, buf, len);
415 }
416 
417 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
418 {
419 	return sfp->write(sfp, a2, addr, buf, len);
420 }
421 
422 static unsigned int sfp_soft_get_state(struct sfp *sfp)
423 {
424 	unsigned int state = 0;
425 	u8 status;
426 
427 	if (sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status)) ==
428 		     sizeof(status)) {
429 		if (status & SFP_STATUS_RX_LOS)
430 			state |= SFP_F_LOS;
431 		if (status & SFP_STATUS_TX_FAULT)
432 			state |= SFP_F_TX_FAULT;
433 	}
434 
435 	return state & sfp->state_soft_mask;
436 }
437 
438 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state)
439 {
440 	u8 status;
441 
442 	if (sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status)) ==
443 		     sizeof(status)) {
444 		if (state & SFP_F_TX_DISABLE)
445 			status |= SFP_STATUS_TX_DISABLE_FORCE;
446 		else
447 			status &= ~SFP_STATUS_TX_DISABLE_FORCE;
448 
449 		sfp_write(sfp, true, SFP_STATUS, &status, sizeof(status));
450 	}
451 }
452 
453 static void sfp_soft_start_poll(struct sfp *sfp)
454 {
455 	const struct sfp_eeprom_id *id = &sfp->id;
456 
457 	sfp->state_soft_mask = 0;
458 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE &&
459 	    !sfp->gpio[GPIO_TX_DISABLE])
460 		sfp->state_soft_mask |= SFP_F_TX_DISABLE;
461 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT &&
462 	    !sfp->gpio[GPIO_TX_FAULT])
463 		sfp->state_soft_mask |= SFP_F_TX_FAULT;
464 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS &&
465 	    !sfp->gpio[GPIO_LOS])
466 		sfp->state_soft_mask |= SFP_F_LOS;
467 
468 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
469 	    !sfp->need_poll)
470 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
471 }
472 
473 static void sfp_soft_stop_poll(struct sfp *sfp)
474 {
475 	sfp->state_soft_mask = 0;
476 }
477 
478 static unsigned int sfp_get_state(struct sfp *sfp)
479 {
480 	unsigned int state = sfp->get_state(sfp);
481 
482 	if (state & SFP_F_PRESENT &&
483 	    sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT))
484 		state |= sfp_soft_get_state(sfp);
485 
486 	return state;
487 }
488 
489 static void sfp_set_state(struct sfp *sfp, unsigned int state)
490 {
491 	sfp->set_state(sfp, state);
492 
493 	if (state & SFP_F_PRESENT &&
494 	    sfp->state_soft_mask & SFP_F_TX_DISABLE)
495 		sfp_soft_set_state(sfp, state);
496 }
497 
498 static unsigned int sfp_check(void *buf, size_t len)
499 {
500 	u8 *p, check;
501 
502 	for (p = buf, check = 0; len; p++, len--)
503 		check += *p;
504 
505 	return check;
506 }
507 
508 /* hwmon */
509 #if IS_ENABLED(CONFIG_HWMON)
510 static umode_t sfp_hwmon_is_visible(const void *data,
511 				    enum hwmon_sensor_types type,
512 				    u32 attr, int channel)
513 {
514 	const struct sfp *sfp = data;
515 
516 	switch (type) {
517 	case hwmon_temp:
518 		switch (attr) {
519 		case hwmon_temp_min_alarm:
520 		case hwmon_temp_max_alarm:
521 		case hwmon_temp_lcrit_alarm:
522 		case hwmon_temp_crit_alarm:
523 		case hwmon_temp_min:
524 		case hwmon_temp_max:
525 		case hwmon_temp_lcrit:
526 		case hwmon_temp_crit:
527 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
528 				return 0;
529 			/* fall through */
530 		case hwmon_temp_input:
531 		case hwmon_temp_label:
532 			return 0444;
533 		default:
534 			return 0;
535 		}
536 	case hwmon_in:
537 		switch (attr) {
538 		case hwmon_in_min_alarm:
539 		case hwmon_in_max_alarm:
540 		case hwmon_in_lcrit_alarm:
541 		case hwmon_in_crit_alarm:
542 		case hwmon_in_min:
543 		case hwmon_in_max:
544 		case hwmon_in_lcrit:
545 		case hwmon_in_crit:
546 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
547 				return 0;
548 			/* fall through */
549 		case hwmon_in_input:
550 		case hwmon_in_label:
551 			return 0444;
552 		default:
553 			return 0;
554 		}
555 	case hwmon_curr:
556 		switch (attr) {
557 		case hwmon_curr_min_alarm:
558 		case hwmon_curr_max_alarm:
559 		case hwmon_curr_lcrit_alarm:
560 		case hwmon_curr_crit_alarm:
561 		case hwmon_curr_min:
562 		case hwmon_curr_max:
563 		case hwmon_curr_lcrit:
564 		case hwmon_curr_crit:
565 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
566 				return 0;
567 			/* fall through */
568 		case hwmon_curr_input:
569 		case hwmon_curr_label:
570 			return 0444;
571 		default:
572 			return 0;
573 		}
574 	case hwmon_power:
575 		/* External calibration of receive power requires
576 		 * floating point arithmetic. Doing that in the kernel
577 		 * is not easy, so just skip it. If the module does
578 		 * not require external calibration, we can however
579 		 * show receiver power, since FP is then not needed.
580 		 */
581 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
582 		    channel == 1)
583 			return 0;
584 		switch (attr) {
585 		case hwmon_power_min_alarm:
586 		case hwmon_power_max_alarm:
587 		case hwmon_power_lcrit_alarm:
588 		case hwmon_power_crit_alarm:
589 		case hwmon_power_min:
590 		case hwmon_power_max:
591 		case hwmon_power_lcrit:
592 		case hwmon_power_crit:
593 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
594 				return 0;
595 			/* fall through */
596 		case hwmon_power_input:
597 		case hwmon_power_label:
598 			return 0444;
599 		default:
600 			return 0;
601 		}
602 	default:
603 		return 0;
604 	}
605 }
606 
607 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
608 {
609 	__be16 val;
610 	int err;
611 
612 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
613 	if (err < 0)
614 		return err;
615 
616 	*value = be16_to_cpu(val);
617 
618 	return 0;
619 }
620 
621 static void sfp_hwmon_to_rx_power(long *value)
622 {
623 	*value = DIV_ROUND_CLOSEST(*value, 10);
624 }
625 
626 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
627 				long *value)
628 {
629 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
630 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
631 }
632 
633 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
634 {
635 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
636 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
637 
638 	if (*value >= 0x8000)
639 		*value -= 0x10000;
640 
641 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
642 }
643 
644 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
645 {
646 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
647 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
648 
649 	*value = DIV_ROUND_CLOSEST(*value, 10);
650 }
651 
652 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
653 {
654 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
655 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
656 
657 	*value = DIV_ROUND_CLOSEST(*value, 500);
658 }
659 
660 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
661 {
662 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
663 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
664 
665 	*value = DIV_ROUND_CLOSEST(*value, 10);
666 }
667 
668 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
669 {
670 	int err;
671 
672 	err = sfp_hwmon_read_sensor(sfp, reg, value);
673 	if (err < 0)
674 		return err;
675 
676 	sfp_hwmon_calibrate_temp(sfp, value);
677 
678 	return 0;
679 }
680 
681 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
682 {
683 	int err;
684 
685 	err = sfp_hwmon_read_sensor(sfp, reg, value);
686 	if (err < 0)
687 		return err;
688 
689 	sfp_hwmon_calibrate_vcc(sfp, value);
690 
691 	return 0;
692 }
693 
694 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
695 {
696 	int err;
697 
698 	err = sfp_hwmon_read_sensor(sfp, reg, value);
699 	if (err < 0)
700 		return err;
701 
702 	sfp_hwmon_calibrate_bias(sfp, value);
703 
704 	return 0;
705 }
706 
707 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
708 {
709 	int err;
710 
711 	err = sfp_hwmon_read_sensor(sfp, reg, value);
712 	if (err < 0)
713 		return err;
714 
715 	sfp_hwmon_calibrate_tx_power(sfp, value);
716 
717 	return 0;
718 }
719 
720 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
721 {
722 	int err;
723 
724 	err = sfp_hwmon_read_sensor(sfp, reg, value);
725 	if (err < 0)
726 		return err;
727 
728 	sfp_hwmon_to_rx_power(value);
729 
730 	return 0;
731 }
732 
733 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
734 {
735 	u8 status;
736 	int err;
737 
738 	switch (attr) {
739 	case hwmon_temp_input:
740 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
741 
742 	case hwmon_temp_lcrit:
743 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
744 		sfp_hwmon_calibrate_temp(sfp, value);
745 		return 0;
746 
747 	case hwmon_temp_min:
748 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
749 		sfp_hwmon_calibrate_temp(sfp, value);
750 		return 0;
751 	case hwmon_temp_max:
752 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
753 		sfp_hwmon_calibrate_temp(sfp, value);
754 		return 0;
755 
756 	case hwmon_temp_crit:
757 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
758 		sfp_hwmon_calibrate_temp(sfp, value);
759 		return 0;
760 
761 	case hwmon_temp_lcrit_alarm:
762 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
763 		if (err < 0)
764 			return err;
765 
766 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
767 		return 0;
768 
769 	case hwmon_temp_min_alarm:
770 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
771 		if (err < 0)
772 			return err;
773 
774 		*value = !!(status & SFP_WARN0_TEMP_LOW);
775 		return 0;
776 
777 	case hwmon_temp_max_alarm:
778 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
779 		if (err < 0)
780 			return err;
781 
782 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
783 		return 0;
784 
785 	case hwmon_temp_crit_alarm:
786 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
787 		if (err < 0)
788 			return err;
789 
790 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
791 		return 0;
792 	default:
793 		return -EOPNOTSUPP;
794 	}
795 
796 	return -EOPNOTSUPP;
797 }
798 
799 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
800 {
801 	u8 status;
802 	int err;
803 
804 	switch (attr) {
805 	case hwmon_in_input:
806 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
807 
808 	case hwmon_in_lcrit:
809 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
810 		sfp_hwmon_calibrate_vcc(sfp, value);
811 		return 0;
812 
813 	case hwmon_in_min:
814 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
815 		sfp_hwmon_calibrate_vcc(sfp, value);
816 		return 0;
817 
818 	case hwmon_in_max:
819 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
820 		sfp_hwmon_calibrate_vcc(sfp, value);
821 		return 0;
822 
823 	case hwmon_in_crit:
824 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
825 		sfp_hwmon_calibrate_vcc(sfp, value);
826 		return 0;
827 
828 	case hwmon_in_lcrit_alarm:
829 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
830 		if (err < 0)
831 			return err;
832 
833 		*value = !!(status & SFP_ALARM0_VCC_LOW);
834 		return 0;
835 
836 	case hwmon_in_min_alarm:
837 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
838 		if (err < 0)
839 			return err;
840 
841 		*value = !!(status & SFP_WARN0_VCC_LOW);
842 		return 0;
843 
844 	case hwmon_in_max_alarm:
845 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
846 		if (err < 0)
847 			return err;
848 
849 		*value = !!(status & SFP_WARN0_VCC_HIGH);
850 		return 0;
851 
852 	case hwmon_in_crit_alarm:
853 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
854 		if (err < 0)
855 			return err;
856 
857 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
858 		return 0;
859 	default:
860 		return -EOPNOTSUPP;
861 	}
862 
863 	return -EOPNOTSUPP;
864 }
865 
866 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
867 {
868 	u8 status;
869 	int err;
870 
871 	switch (attr) {
872 	case hwmon_curr_input:
873 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
874 
875 	case hwmon_curr_lcrit:
876 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
877 		sfp_hwmon_calibrate_bias(sfp, value);
878 		return 0;
879 
880 	case hwmon_curr_min:
881 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
882 		sfp_hwmon_calibrate_bias(sfp, value);
883 		return 0;
884 
885 	case hwmon_curr_max:
886 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
887 		sfp_hwmon_calibrate_bias(sfp, value);
888 		return 0;
889 
890 	case hwmon_curr_crit:
891 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
892 		sfp_hwmon_calibrate_bias(sfp, value);
893 		return 0;
894 
895 	case hwmon_curr_lcrit_alarm:
896 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
897 		if (err < 0)
898 			return err;
899 
900 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
901 		return 0;
902 
903 	case hwmon_curr_min_alarm:
904 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
905 		if (err < 0)
906 			return err;
907 
908 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
909 		return 0;
910 
911 	case hwmon_curr_max_alarm:
912 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
913 		if (err < 0)
914 			return err;
915 
916 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
917 		return 0;
918 
919 	case hwmon_curr_crit_alarm:
920 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
921 		if (err < 0)
922 			return err;
923 
924 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
925 		return 0;
926 	default:
927 		return -EOPNOTSUPP;
928 	}
929 
930 	return -EOPNOTSUPP;
931 }
932 
933 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
934 {
935 	u8 status;
936 	int err;
937 
938 	switch (attr) {
939 	case hwmon_power_input:
940 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
941 
942 	case hwmon_power_lcrit:
943 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
944 		sfp_hwmon_calibrate_tx_power(sfp, value);
945 		return 0;
946 
947 	case hwmon_power_min:
948 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
949 		sfp_hwmon_calibrate_tx_power(sfp, value);
950 		return 0;
951 
952 	case hwmon_power_max:
953 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
954 		sfp_hwmon_calibrate_tx_power(sfp, value);
955 		return 0;
956 
957 	case hwmon_power_crit:
958 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
959 		sfp_hwmon_calibrate_tx_power(sfp, value);
960 		return 0;
961 
962 	case hwmon_power_lcrit_alarm:
963 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
964 		if (err < 0)
965 			return err;
966 
967 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
968 		return 0;
969 
970 	case hwmon_power_min_alarm:
971 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
972 		if (err < 0)
973 			return err;
974 
975 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
976 		return 0;
977 
978 	case hwmon_power_max_alarm:
979 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
980 		if (err < 0)
981 			return err;
982 
983 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
984 		return 0;
985 
986 	case hwmon_power_crit_alarm:
987 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
988 		if (err < 0)
989 			return err;
990 
991 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
992 		return 0;
993 	default:
994 		return -EOPNOTSUPP;
995 	}
996 
997 	return -EOPNOTSUPP;
998 }
999 
1000 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1001 {
1002 	u8 status;
1003 	int err;
1004 
1005 	switch (attr) {
1006 	case hwmon_power_input:
1007 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1008 
1009 	case hwmon_power_lcrit:
1010 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1011 		sfp_hwmon_to_rx_power(value);
1012 		return 0;
1013 
1014 	case hwmon_power_min:
1015 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1016 		sfp_hwmon_to_rx_power(value);
1017 		return 0;
1018 
1019 	case hwmon_power_max:
1020 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1021 		sfp_hwmon_to_rx_power(value);
1022 		return 0;
1023 
1024 	case hwmon_power_crit:
1025 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1026 		sfp_hwmon_to_rx_power(value);
1027 		return 0;
1028 
1029 	case hwmon_power_lcrit_alarm:
1030 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1031 		if (err < 0)
1032 			return err;
1033 
1034 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1035 		return 0;
1036 
1037 	case hwmon_power_min_alarm:
1038 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1039 		if (err < 0)
1040 			return err;
1041 
1042 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1043 		return 0;
1044 
1045 	case hwmon_power_max_alarm:
1046 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1047 		if (err < 0)
1048 			return err;
1049 
1050 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1051 		return 0;
1052 
1053 	case hwmon_power_crit_alarm:
1054 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1055 		if (err < 0)
1056 			return err;
1057 
1058 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1059 		return 0;
1060 	default:
1061 		return -EOPNOTSUPP;
1062 	}
1063 
1064 	return -EOPNOTSUPP;
1065 }
1066 
1067 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1068 			  u32 attr, int channel, long *value)
1069 {
1070 	struct sfp *sfp = dev_get_drvdata(dev);
1071 
1072 	switch (type) {
1073 	case hwmon_temp:
1074 		return sfp_hwmon_temp(sfp, attr, value);
1075 	case hwmon_in:
1076 		return sfp_hwmon_vcc(sfp, attr, value);
1077 	case hwmon_curr:
1078 		return sfp_hwmon_bias(sfp, attr, value);
1079 	case hwmon_power:
1080 		switch (channel) {
1081 		case 0:
1082 			return sfp_hwmon_tx_power(sfp, attr, value);
1083 		case 1:
1084 			return sfp_hwmon_rx_power(sfp, attr, value);
1085 		default:
1086 			return -EOPNOTSUPP;
1087 		}
1088 	default:
1089 		return -EOPNOTSUPP;
1090 	}
1091 }
1092 
1093 static const char *const sfp_hwmon_power_labels[] = {
1094 	"TX_power",
1095 	"RX_power",
1096 };
1097 
1098 static int sfp_hwmon_read_string(struct device *dev,
1099 				 enum hwmon_sensor_types type,
1100 				 u32 attr, int channel, const char **str)
1101 {
1102 	switch (type) {
1103 	case hwmon_curr:
1104 		switch (attr) {
1105 		case hwmon_curr_label:
1106 			*str = "bias";
1107 			return 0;
1108 		default:
1109 			return -EOPNOTSUPP;
1110 		}
1111 		break;
1112 	case hwmon_temp:
1113 		switch (attr) {
1114 		case hwmon_temp_label:
1115 			*str = "temperature";
1116 			return 0;
1117 		default:
1118 			return -EOPNOTSUPP;
1119 		}
1120 		break;
1121 	case hwmon_in:
1122 		switch (attr) {
1123 		case hwmon_in_label:
1124 			*str = "VCC";
1125 			return 0;
1126 		default:
1127 			return -EOPNOTSUPP;
1128 		}
1129 		break;
1130 	case hwmon_power:
1131 		switch (attr) {
1132 		case hwmon_power_label:
1133 			*str = sfp_hwmon_power_labels[channel];
1134 			return 0;
1135 		default:
1136 			return -EOPNOTSUPP;
1137 		}
1138 		break;
1139 	default:
1140 		return -EOPNOTSUPP;
1141 	}
1142 
1143 	return -EOPNOTSUPP;
1144 }
1145 
1146 static const struct hwmon_ops sfp_hwmon_ops = {
1147 	.is_visible = sfp_hwmon_is_visible,
1148 	.read = sfp_hwmon_read,
1149 	.read_string = sfp_hwmon_read_string,
1150 };
1151 
1152 static u32 sfp_hwmon_chip_config[] = {
1153 	HWMON_C_REGISTER_TZ,
1154 	0,
1155 };
1156 
1157 static const struct hwmon_channel_info sfp_hwmon_chip = {
1158 	.type = hwmon_chip,
1159 	.config = sfp_hwmon_chip_config,
1160 };
1161 
1162 static u32 sfp_hwmon_temp_config[] = {
1163 	HWMON_T_INPUT |
1164 	HWMON_T_MAX | HWMON_T_MIN |
1165 	HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1166 	HWMON_T_CRIT | HWMON_T_LCRIT |
1167 	HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1168 	HWMON_T_LABEL,
1169 	0,
1170 };
1171 
1172 static const struct hwmon_channel_info sfp_hwmon_temp_channel_info = {
1173 	.type = hwmon_temp,
1174 	.config = sfp_hwmon_temp_config,
1175 };
1176 
1177 static u32 sfp_hwmon_vcc_config[] = {
1178 	HWMON_I_INPUT |
1179 	HWMON_I_MAX | HWMON_I_MIN |
1180 	HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1181 	HWMON_I_CRIT | HWMON_I_LCRIT |
1182 	HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1183 	HWMON_I_LABEL,
1184 	0,
1185 };
1186 
1187 static const struct hwmon_channel_info sfp_hwmon_vcc_channel_info = {
1188 	.type = hwmon_in,
1189 	.config = sfp_hwmon_vcc_config,
1190 };
1191 
1192 static u32 sfp_hwmon_bias_config[] = {
1193 	HWMON_C_INPUT |
1194 	HWMON_C_MAX | HWMON_C_MIN |
1195 	HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1196 	HWMON_C_CRIT | HWMON_C_LCRIT |
1197 	HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1198 	HWMON_C_LABEL,
1199 	0,
1200 };
1201 
1202 static const struct hwmon_channel_info sfp_hwmon_bias_channel_info = {
1203 	.type = hwmon_curr,
1204 	.config = sfp_hwmon_bias_config,
1205 };
1206 
1207 static u32 sfp_hwmon_power_config[] = {
1208 	/* Transmit power */
1209 	HWMON_P_INPUT |
1210 	HWMON_P_MAX | HWMON_P_MIN |
1211 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1212 	HWMON_P_CRIT | HWMON_P_LCRIT |
1213 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1214 	HWMON_P_LABEL,
1215 	/* Receive power */
1216 	HWMON_P_INPUT |
1217 	HWMON_P_MAX | HWMON_P_MIN |
1218 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1219 	HWMON_P_CRIT | HWMON_P_LCRIT |
1220 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1221 	HWMON_P_LABEL,
1222 	0,
1223 };
1224 
1225 static const struct hwmon_channel_info sfp_hwmon_power_channel_info = {
1226 	.type = hwmon_power,
1227 	.config = sfp_hwmon_power_config,
1228 };
1229 
1230 static const struct hwmon_channel_info *sfp_hwmon_info[] = {
1231 	&sfp_hwmon_chip,
1232 	&sfp_hwmon_vcc_channel_info,
1233 	&sfp_hwmon_temp_channel_info,
1234 	&sfp_hwmon_bias_channel_info,
1235 	&sfp_hwmon_power_channel_info,
1236 	NULL,
1237 };
1238 
1239 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1240 	.ops = &sfp_hwmon_ops,
1241 	.info = sfp_hwmon_info,
1242 };
1243 
1244 static void sfp_hwmon_probe(struct work_struct *work)
1245 {
1246 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1247 	int err, i;
1248 
1249 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1250 	if (err < 0) {
1251 		if (sfp->hwmon_tries--) {
1252 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1253 					 T_PROBE_RETRY_SLOW);
1254 		} else {
1255 			dev_warn(sfp->dev, "hwmon probe failed: %d\n", err);
1256 		}
1257 		return;
1258 	}
1259 
1260 	sfp->hwmon_name = kstrdup(dev_name(sfp->dev), GFP_KERNEL);
1261 	if (!sfp->hwmon_name) {
1262 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1263 		return;
1264 	}
1265 
1266 	for (i = 0; sfp->hwmon_name[i]; i++)
1267 		if (hwmon_is_bad_char(sfp->hwmon_name[i]))
1268 			sfp->hwmon_name[i] = '_';
1269 
1270 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1271 							 sfp->hwmon_name, sfp,
1272 							 &sfp_hwmon_chip_info,
1273 							 NULL);
1274 	if (IS_ERR(sfp->hwmon_dev))
1275 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1276 			PTR_ERR(sfp->hwmon_dev));
1277 }
1278 
1279 static int sfp_hwmon_insert(struct sfp *sfp)
1280 {
1281 	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
1282 		return 0;
1283 
1284 	if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
1285 		return 0;
1286 
1287 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1288 		/* This driver in general does not support address
1289 		 * change.
1290 		 */
1291 		return 0;
1292 
1293 	mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1294 	sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1295 
1296 	return 0;
1297 }
1298 
1299 static void sfp_hwmon_remove(struct sfp *sfp)
1300 {
1301 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1302 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1303 		hwmon_device_unregister(sfp->hwmon_dev);
1304 		sfp->hwmon_dev = NULL;
1305 		kfree(sfp->hwmon_name);
1306 	}
1307 }
1308 
1309 static int sfp_hwmon_init(struct sfp *sfp)
1310 {
1311 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1312 
1313 	return 0;
1314 }
1315 
1316 static void sfp_hwmon_exit(struct sfp *sfp)
1317 {
1318 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1319 }
1320 #else
1321 static int sfp_hwmon_insert(struct sfp *sfp)
1322 {
1323 	return 0;
1324 }
1325 
1326 static void sfp_hwmon_remove(struct sfp *sfp)
1327 {
1328 }
1329 
1330 static int sfp_hwmon_init(struct sfp *sfp)
1331 {
1332 	return 0;
1333 }
1334 
1335 static void sfp_hwmon_exit(struct sfp *sfp)
1336 {
1337 }
1338 #endif
1339 
1340 /* Helpers */
1341 static void sfp_module_tx_disable(struct sfp *sfp)
1342 {
1343 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1344 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1345 	sfp->state |= SFP_F_TX_DISABLE;
1346 	sfp_set_state(sfp, sfp->state);
1347 }
1348 
1349 static void sfp_module_tx_enable(struct sfp *sfp)
1350 {
1351 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1352 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1353 	sfp->state &= ~SFP_F_TX_DISABLE;
1354 	sfp_set_state(sfp, sfp->state);
1355 }
1356 
1357 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1358 {
1359 	unsigned int state = sfp->state;
1360 
1361 	if (state & SFP_F_TX_DISABLE)
1362 		return;
1363 
1364 	sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1365 
1366 	udelay(T_RESET_US);
1367 
1368 	sfp_set_state(sfp, state);
1369 }
1370 
1371 /* SFP state machine */
1372 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1373 {
1374 	if (timeout)
1375 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1376 				 timeout);
1377 	else
1378 		cancel_delayed_work(&sfp->timeout);
1379 }
1380 
1381 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1382 			unsigned int timeout)
1383 {
1384 	sfp->sm_state = state;
1385 	sfp_sm_set_timer(sfp, timeout);
1386 }
1387 
1388 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1389 			    unsigned int timeout)
1390 {
1391 	sfp->sm_mod_state = state;
1392 	sfp_sm_set_timer(sfp, timeout);
1393 }
1394 
1395 static void sfp_sm_phy_detach(struct sfp *sfp)
1396 {
1397 	phy_stop(sfp->mod_phy);
1398 	sfp_remove_phy(sfp->sfp_bus);
1399 	phy_device_remove(sfp->mod_phy);
1400 	phy_device_free(sfp->mod_phy);
1401 	sfp->mod_phy = NULL;
1402 }
1403 
1404 static void sfp_sm_probe_phy(struct sfp *sfp)
1405 {
1406 	struct phy_device *phy;
1407 	int err;
1408 
1409 	phy = mdiobus_scan(sfp->i2c_mii, SFP_PHY_ADDR);
1410 	if (phy == ERR_PTR(-ENODEV)) {
1411 		dev_info(sfp->dev, "no PHY detected\n");
1412 		return;
1413 	}
1414 	if (IS_ERR(phy)) {
1415 		dev_err(sfp->dev, "mdiobus scan returned %ld\n", PTR_ERR(phy));
1416 		return;
1417 	}
1418 
1419 	err = sfp_add_phy(sfp->sfp_bus, phy);
1420 	if (err) {
1421 		phy_device_remove(phy);
1422 		phy_device_free(phy);
1423 		dev_err(sfp->dev, "sfp_add_phy failed: %d\n", err);
1424 		return;
1425 	}
1426 
1427 	sfp->mod_phy = phy;
1428 	phy_start(phy);
1429 }
1430 
1431 static void sfp_sm_link_up(struct sfp *sfp)
1432 {
1433 	sfp_link_up(sfp->sfp_bus);
1434 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1435 }
1436 
1437 static void sfp_sm_link_down(struct sfp *sfp)
1438 {
1439 	sfp_link_down(sfp->sfp_bus);
1440 }
1441 
1442 static void sfp_sm_link_check_los(struct sfp *sfp)
1443 {
1444 	unsigned int los = sfp->state & SFP_F_LOS;
1445 
1446 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1447 	 * are set, we assume that no LOS signal is available.
1448 	 */
1449 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED))
1450 		los ^= SFP_F_LOS;
1451 	else if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL)))
1452 		los = 0;
1453 
1454 	if (los)
1455 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1456 	else
1457 		sfp_sm_link_up(sfp);
1458 }
1459 
1460 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1461 {
1462 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1463 		event == SFP_E_LOS_LOW) ||
1464 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1465 		event == SFP_E_LOS_HIGH);
1466 }
1467 
1468 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1469 {
1470 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1471 		event == SFP_E_LOS_HIGH) ||
1472 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1473 		event == SFP_E_LOS_LOW);
1474 }
1475 
1476 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1477 {
1478 	if (sfp->sm_retries && !--sfp->sm_retries) {
1479 		dev_err(sfp->dev,
1480 			"module persistently indicates fault, disabling\n");
1481 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1482 	} else {
1483 		if (warn)
1484 			dev_err(sfp->dev, "module transmit fault indicated\n");
1485 
1486 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1487 	}
1488 }
1489 
1490 static void sfp_sm_probe_for_phy(struct sfp *sfp)
1491 {
1492 	/* Setting the serdes link mode is guesswork: there's no
1493 	 * field in the EEPROM which indicates what mode should
1494 	 * be used.
1495 	 *
1496 	 * If it's a gigabit-only fiber module, it probably does
1497 	 * not have a PHY, so switch to 802.3z negotiation mode.
1498 	 * Otherwise, switch to SGMII mode (which is required to
1499 	 * support non-gigabit speeds) and probe for a PHY.
1500 	 */
1501 	if (sfp->id.base.e1000_base_t ||
1502 	    sfp->id.base.e100_base_lx ||
1503 	    sfp->id.base.e100_base_fx)
1504 		sfp_sm_probe_phy(sfp);
1505 }
1506 
1507 static int sfp_module_parse_power(struct sfp *sfp)
1508 {
1509 	u32 power_mW = 1000;
1510 
1511 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1512 		power_mW = 1500;
1513 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1514 		power_mW = 2000;
1515 
1516 	if (power_mW > sfp->max_power_mW) {
1517 		/* Module power specification exceeds the allowed maximum. */
1518 		if (sfp->id.ext.sff8472_compliance ==
1519 			SFP_SFF8472_COMPLIANCE_NONE &&
1520 		    !(sfp->id.ext.diagmon & SFP_DIAGMON_DDM)) {
1521 			/* The module appears not to implement bus address
1522 			 * 0xa2, so assume that the module powers up in the
1523 			 * indicated mode.
1524 			 */
1525 			dev_err(sfp->dev,
1526 				"Host does not support %u.%uW modules\n",
1527 				power_mW / 1000, (power_mW / 100) % 10);
1528 			return -EINVAL;
1529 		} else {
1530 			dev_warn(sfp->dev,
1531 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1532 				 power_mW / 1000, (power_mW / 100) % 10);
1533 			return 0;
1534 		}
1535 	}
1536 
1537 	/* If the module requires a higher power mode, but also requires
1538 	 * an address change sequence, warn the user that the module may
1539 	 * not be functional.
1540 	 */
1541 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE && power_mW > 1000) {
1542 		dev_warn(sfp->dev,
1543 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1544 			 power_mW / 1000, (power_mW / 100) % 10);
1545 		return 0;
1546 	}
1547 
1548 	sfp->module_power_mW = power_mW;
1549 
1550 	return 0;
1551 }
1552 
1553 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1554 {
1555 	u8 val;
1556 	int err;
1557 
1558 	err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1559 	if (err != sizeof(val)) {
1560 		dev_err(sfp->dev, "Failed to read EEPROM: %d\n", err);
1561 		return -EAGAIN;
1562 	}
1563 
1564 	if (enable)
1565 		val |= BIT(0);
1566 	else
1567 		val &= ~BIT(0);
1568 
1569 	err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1570 	if (err != sizeof(val)) {
1571 		dev_err(sfp->dev, "Failed to write EEPROM: %d\n", err);
1572 		return -EAGAIN;
1573 	}
1574 
1575 	if (enable)
1576 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1577 			 sfp->module_power_mW / 1000,
1578 			 (sfp->module_power_mW / 100) % 10);
1579 
1580 	return 0;
1581 }
1582 
1583 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
1584 {
1585 	/* SFP module inserted - read I2C data */
1586 	struct sfp_eeprom_id id;
1587 	bool cotsworks;
1588 	u8 check;
1589 	int ret;
1590 
1591 	ret = sfp_read(sfp, false, 0, &id, sizeof(id));
1592 	if (ret < 0) {
1593 		if (report)
1594 			dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
1595 		return -EAGAIN;
1596 	}
1597 
1598 	if (ret != sizeof(id)) {
1599 		dev_err(sfp->dev, "EEPROM short read: %d\n", ret);
1600 		return -EAGAIN;
1601 	}
1602 
1603 	/* Cotsworks do not seem to update the checksums when they
1604 	 * do the final programming with the final module part number,
1605 	 * serial number and date code.
1606 	 */
1607 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
1608 
1609 	/* Validate the checksum over the base structure */
1610 	check = sfp_check(&id.base, sizeof(id.base) - 1);
1611 	if (check != id.base.cc_base) {
1612 		if (cotsworks) {
1613 			dev_warn(sfp->dev,
1614 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
1615 				 check, id.base.cc_base);
1616 		} else {
1617 			dev_err(sfp->dev,
1618 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
1619 				check, id.base.cc_base);
1620 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1621 				       16, 1, &id, sizeof(id), true);
1622 			return -EINVAL;
1623 		}
1624 	}
1625 
1626 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
1627 	if (check != id.ext.cc_ext) {
1628 		if (cotsworks) {
1629 			dev_warn(sfp->dev,
1630 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
1631 				 check, id.ext.cc_ext);
1632 		} else {
1633 			dev_err(sfp->dev,
1634 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
1635 				check, id.ext.cc_ext);
1636 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1637 				       16, 1, &id, sizeof(id), true);
1638 			memset(&id.ext, 0, sizeof(id.ext));
1639 		}
1640 	}
1641 
1642 	sfp->id = id;
1643 
1644 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
1645 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
1646 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
1647 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
1648 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
1649 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
1650 
1651 	/* Check whether we support this module */
1652 	if (!sfp->type->module_supported(&id)) {
1653 		dev_err(sfp->dev,
1654 			"module is not supported - phys id 0x%02x 0x%02x\n",
1655 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
1656 		return -EINVAL;
1657 	}
1658 
1659 	/* If the module requires address swap mode, warn about it */
1660 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1661 		dev_warn(sfp->dev,
1662 			 "module address swap to access page 0xA2 is not supported.\n");
1663 
1664 	/* Parse the module power requirement */
1665 	ret = sfp_module_parse_power(sfp);
1666 	if (ret < 0)
1667 		return ret;
1668 
1669 	if (!memcmp(id.base.vendor_name, "ALCATELLUCENT   ", 16) &&
1670 	    !memcmp(id.base.vendor_pn, "3FE46541AA      ", 16))
1671 		sfp->module_t_start_up = T_START_UP_BAD_GPON;
1672 	else
1673 		sfp->module_t_start_up = T_START_UP;
1674 
1675 	return 0;
1676 }
1677 
1678 static void sfp_sm_mod_remove(struct sfp *sfp)
1679 {
1680 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
1681 		sfp_module_remove(sfp->sfp_bus);
1682 
1683 	sfp_hwmon_remove(sfp);
1684 
1685 	memset(&sfp->id, 0, sizeof(sfp->id));
1686 	sfp->module_power_mW = 0;
1687 
1688 	dev_info(sfp->dev, "module removed\n");
1689 }
1690 
1691 /* This state machine tracks the upstream's state */
1692 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
1693 {
1694 	switch (sfp->sm_dev_state) {
1695 	default:
1696 		if (event == SFP_E_DEV_ATTACH)
1697 			sfp->sm_dev_state = SFP_DEV_DOWN;
1698 		break;
1699 
1700 	case SFP_DEV_DOWN:
1701 		if (event == SFP_E_DEV_DETACH)
1702 			sfp->sm_dev_state = SFP_DEV_DETACHED;
1703 		else if (event == SFP_E_DEV_UP)
1704 			sfp->sm_dev_state = SFP_DEV_UP;
1705 		break;
1706 
1707 	case SFP_DEV_UP:
1708 		if (event == SFP_E_DEV_DETACH)
1709 			sfp->sm_dev_state = SFP_DEV_DETACHED;
1710 		else if (event == SFP_E_DEV_DOWN)
1711 			sfp->sm_dev_state = SFP_DEV_DOWN;
1712 		break;
1713 	}
1714 }
1715 
1716 /* This state machine tracks the insert/remove state of the module, probes
1717  * the on-board EEPROM, and sets up the power level.
1718  */
1719 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
1720 {
1721 	int err;
1722 
1723 	/* Handle remove event globally, it resets this state machine */
1724 	if (event == SFP_E_REMOVE) {
1725 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
1726 			sfp_sm_mod_remove(sfp);
1727 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
1728 		return;
1729 	}
1730 
1731 	/* Handle device detach globally */
1732 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
1733 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
1734 		if (sfp->module_power_mW > 1000 &&
1735 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
1736 			sfp_sm_mod_hpower(sfp, false);
1737 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
1738 		return;
1739 	}
1740 
1741 	switch (sfp->sm_mod_state) {
1742 	default:
1743 		if (event == SFP_E_INSERT) {
1744 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
1745 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
1746 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
1747 		}
1748 		break;
1749 
1750 	case SFP_MOD_PROBE:
1751 		/* Wait for T_PROBE_INIT to time out */
1752 		if (event != SFP_E_TIMEOUT)
1753 			break;
1754 
1755 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
1756 		if (err == -EAGAIN) {
1757 			if (sfp->sm_mod_tries_init &&
1758 			   --sfp->sm_mod_tries_init) {
1759 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
1760 				break;
1761 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
1762 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
1763 					dev_warn(sfp->dev,
1764 						 "please wait, module slow to respond\n");
1765 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
1766 				break;
1767 			}
1768 		}
1769 		if (err < 0) {
1770 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1771 			break;
1772 		}
1773 
1774 		err = sfp_hwmon_insert(sfp);
1775 		if (err)
1776 			dev_warn(sfp->dev, "hwmon probe failed: %d\n", err);
1777 
1778 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
1779 		/* fall through */
1780 	case SFP_MOD_WAITDEV:
1781 		/* Ensure that the device is attached before proceeding */
1782 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
1783 			break;
1784 
1785 		/* Report the module insertion to the upstream device */
1786 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id);
1787 		if (err < 0) {
1788 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1789 			break;
1790 		}
1791 
1792 		/* If this is a power level 1 module, we are done */
1793 		if (sfp->module_power_mW <= 1000)
1794 			goto insert;
1795 
1796 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
1797 		/* fall through */
1798 	case SFP_MOD_HPOWER:
1799 		/* Enable high power mode */
1800 		err = sfp_sm_mod_hpower(sfp, true);
1801 		if (err < 0) {
1802 			if (err != -EAGAIN) {
1803 				sfp_module_remove(sfp->sfp_bus);
1804 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1805 			} else {
1806 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
1807 			}
1808 			break;
1809 		}
1810 
1811 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
1812 		break;
1813 
1814 	case SFP_MOD_WAITPWR:
1815 		/* Wait for T_HPOWER_LEVEL to time out */
1816 		if (event != SFP_E_TIMEOUT)
1817 			break;
1818 
1819 	insert:
1820 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
1821 		break;
1822 
1823 	case SFP_MOD_PRESENT:
1824 	case SFP_MOD_ERROR:
1825 		break;
1826 	}
1827 }
1828 
1829 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
1830 {
1831 	unsigned long timeout;
1832 
1833 	/* Some events are global */
1834 	if (sfp->sm_state != SFP_S_DOWN &&
1835 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
1836 	     sfp->sm_dev_state != SFP_DEV_UP)) {
1837 		if (sfp->sm_state == SFP_S_LINK_UP &&
1838 		    sfp->sm_dev_state == SFP_DEV_UP)
1839 			sfp_sm_link_down(sfp);
1840 		if (sfp->mod_phy)
1841 			sfp_sm_phy_detach(sfp);
1842 		sfp_module_tx_disable(sfp);
1843 		sfp_soft_stop_poll(sfp);
1844 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
1845 		return;
1846 	}
1847 
1848 	/* The main state machine */
1849 	switch (sfp->sm_state) {
1850 	case SFP_S_DOWN:
1851 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
1852 		    sfp->sm_dev_state != SFP_DEV_UP)
1853 			break;
1854 
1855 		if (!(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE))
1856 			sfp_soft_start_poll(sfp);
1857 
1858 		sfp_module_tx_enable(sfp);
1859 
1860 		/* Initialise the fault clearance retries */
1861 		sfp->sm_retries = 5;
1862 
1863 		/* We need to check the TX_FAULT state, which is not defined
1864 		 * while TX_DISABLE is asserted. The earliest we want to do
1865 		 * anything (such as probe for a PHY) is 50ms.
1866 		 */
1867 		sfp_sm_next(sfp, SFP_S_WAIT, T_WAIT);
1868 		break;
1869 
1870 	case SFP_S_WAIT:
1871 		if (event != SFP_E_TIMEOUT)
1872 			break;
1873 
1874 		if (sfp->state & SFP_F_TX_FAULT) {
1875 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
1876 			 * from the TX_DISABLE deassertion for the module to
1877 			 * initialise, which is indicated by TX_FAULT
1878 			 * deasserting.
1879 			 */
1880 			timeout = sfp->module_t_start_up;
1881 			if (timeout > T_WAIT)
1882 				timeout -= T_WAIT;
1883 			else
1884 				timeout = 1;
1885 
1886 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
1887 		} else {
1888 			/* TX_FAULT is not asserted, assume the module has
1889 			 * finished initialising.
1890 			 */
1891 			goto init_done;
1892 		}
1893 		break;
1894 
1895 	case SFP_S_INIT:
1896 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
1897 			/* TX_FAULT is still asserted after t_init or
1898 			 * or t_start_up, so assume there is a fault.
1899 			 */
1900 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
1901 				     sfp->sm_retries == 5);
1902 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
1903 	init_done:	/* TX_FAULT deasserted or we timed out with TX_FAULT
1904 			 * clear.  Probe for the PHY and check the LOS state.
1905 			 */
1906 			sfp_sm_probe_for_phy(sfp);
1907 			sfp_sm_link_check_los(sfp);
1908 
1909 			/* Reset the fault retry count */
1910 			sfp->sm_retries = 5;
1911 		}
1912 		break;
1913 
1914 	case SFP_S_INIT_TX_FAULT:
1915 		if (event == SFP_E_TIMEOUT) {
1916 			sfp_module_tx_fault_reset(sfp);
1917 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
1918 		}
1919 		break;
1920 
1921 	case SFP_S_WAIT_LOS:
1922 		if (event == SFP_E_TX_FAULT)
1923 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
1924 		else if (sfp_los_event_inactive(sfp, event))
1925 			sfp_sm_link_up(sfp);
1926 		break;
1927 
1928 	case SFP_S_LINK_UP:
1929 		if (event == SFP_E_TX_FAULT) {
1930 			sfp_sm_link_down(sfp);
1931 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
1932 		} else if (sfp_los_event_active(sfp, event)) {
1933 			sfp_sm_link_down(sfp);
1934 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1935 		}
1936 		break;
1937 
1938 	case SFP_S_TX_FAULT:
1939 		if (event == SFP_E_TIMEOUT) {
1940 			sfp_module_tx_fault_reset(sfp);
1941 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
1942 		}
1943 		break;
1944 
1945 	case SFP_S_REINIT:
1946 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
1947 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
1948 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
1949 			dev_info(sfp->dev, "module transmit fault recovered\n");
1950 			sfp_sm_link_check_los(sfp);
1951 		}
1952 		break;
1953 
1954 	case SFP_S_TX_DISABLE:
1955 		break;
1956 	}
1957 }
1958 
1959 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
1960 {
1961 	mutex_lock(&sfp->sm_mutex);
1962 
1963 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
1964 		mod_state_to_str(sfp->sm_mod_state),
1965 		dev_state_to_str(sfp->sm_dev_state),
1966 		sm_state_to_str(sfp->sm_state),
1967 		event_to_str(event));
1968 
1969 	sfp_sm_device(sfp, event);
1970 	sfp_sm_module(sfp, event);
1971 	sfp_sm_main(sfp, event);
1972 
1973 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
1974 		mod_state_to_str(sfp->sm_mod_state),
1975 		dev_state_to_str(sfp->sm_dev_state),
1976 		sm_state_to_str(sfp->sm_state));
1977 
1978 	mutex_unlock(&sfp->sm_mutex);
1979 }
1980 
1981 static void sfp_attach(struct sfp *sfp)
1982 {
1983 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
1984 }
1985 
1986 static void sfp_detach(struct sfp *sfp)
1987 {
1988 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
1989 }
1990 
1991 static void sfp_start(struct sfp *sfp)
1992 {
1993 	sfp_sm_event(sfp, SFP_E_DEV_UP);
1994 }
1995 
1996 static void sfp_stop(struct sfp *sfp)
1997 {
1998 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
1999 }
2000 
2001 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2002 {
2003 	/* locking... and check module is present */
2004 
2005 	if (sfp->id.ext.sff8472_compliance &&
2006 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2007 		modinfo->type = ETH_MODULE_SFF_8472;
2008 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2009 	} else {
2010 		modinfo->type = ETH_MODULE_SFF_8079;
2011 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2012 	}
2013 	return 0;
2014 }
2015 
2016 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2017 			     u8 *data)
2018 {
2019 	unsigned int first, last, len;
2020 	int ret;
2021 
2022 	if (ee->len == 0)
2023 		return -EINVAL;
2024 
2025 	first = ee->offset;
2026 	last = ee->offset + ee->len;
2027 	if (first < ETH_MODULE_SFF_8079_LEN) {
2028 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2029 		len -= first;
2030 
2031 		ret = sfp_read(sfp, false, first, data, len);
2032 		if (ret < 0)
2033 			return ret;
2034 
2035 		first += len;
2036 		data += len;
2037 	}
2038 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2039 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2040 		len -= first;
2041 		first -= ETH_MODULE_SFF_8079_LEN;
2042 
2043 		ret = sfp_read(sfp, true, first, data, len);
2044 		if (ret < 0)
2045 			return ret;
2046 	}
2047 	return 0;
2048 }
2049 
2050 static const struct sfp_socket_ops sfp_module_ops = {
2051 	.attach = sfp_attach,
2052 	.detach = sfp_detach,
2053 	.start = sfp_start,
2054 	.stop = sfp_stop,
2055 	.module_info = sfp_module_info,
2056 	.module_eeprom = sfp_module_eeprom,
2057 };
2058 
2059 static void sfp_timeout(struct work_struct *work)
2060 {
2061 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2062 
2063 	rtnl_lock();
2064 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2065 	rtnl_unlock();
2066 }
2067 
2068 static void sfp_check_state(struct sfp *sfp)
2069 {
2070 	unsigned int state, i, changed;
2071 
2072 	mutex_lock(&sfp->st_mutex);
2073 	state = sfp_get_state(sfp);
2074 	changed = state ^ sfp->state;
2075 	changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2076 
2077 	for (i = 0; i < GPIO_MAX; i++)
2078 		if (changed & BIT(i))
2079 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_of_names[i],
2080 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2081 
2082 	state |= sfp->state & (SFP_F_TX_DISABLE | SFP_F_RATE_SELECT);
2083 	sfp->state = state;
2084 
2085 	rtnl_lock();
2086 	if (changed & SFP_F_PRESENT)
2087 		sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2088 				SFP_E_INSERT : SFP_E_REMOVE);
2089 
2090 	if (changed & SFP_F_TX_FAULT)
2091 		sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2092 				SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2093 
2094 	if (changed & SFP_F_LOS)
2095 		sfp_sm_event(sfp, state & SFP_F_LOS ?
2096 				SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2097 	rtnl_unlock();
2098 	mutex_unlock(&sfp->st_mutex);
2099 }
2100 
2101 static irqreturn_t sfp_irq(int irq, void *data)
2102 {
2103 	struct sfp *sfp = data;
2104 
2105 	sfp_check_state(sfp);
2106 
2107 	return IRQ_HANDLED;
2108 }
2109 
2110 static void sfp_poll(struct work_struct *work)
2111 {
2112 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2113 
2114 	sfp_check_state(sfp);
2115 
2116 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2117 	    sfp->need_poll)
2118 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2119 }
2120 
2121 static struct sfp *sfp_alloc(struct device *dev)
2122 {
2123 	struct sfp *sfp;
2124 
2125 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2126 	if (!sfp)
2127 		return ERR_PTR(-ENOMEM);
2128 
2129 	sfp->dev = dev;
2130 
2131 	mutex_init(&sfp->sm_mutex);
2132 	mutex_init(&sfp->st_mutex);
2133 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2134 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2135 
2136 	sfp_hwmon_init(sfp);
2137 
2138 	return sfp;
2139 }
2140 
2141 static void sfp_cleanup(void *data)
2142 {
2143 	struct sfp *sfp = data;
2144 
2145 	sfp_hwmon_exit(sfp);
2146 
2147 	cancel_delayed_work_sync(&sfp->poll);
2148 	cancel_delayed_work_sync(&sfp->timeout);
2149 	if (sfp->i2c_mii) {
2150 		mdiobus_unregister(sfp->i2c_mii);
2151 		mdiobus_free(sfp->i2c_mii);
2152 	}
2153 	if (sfp->i2c)
2154 		i2c_put_adapter(sfp->i2c);
2155 	kfree(sfp);
2156 }
2157 
2158 static int sfp_probe(struct platform_device *pdev)
2159 {
2160 	const struct sff_data *sff;
2161 	struct i2c_adapter *i2c;
2162 	struct sfp *sfp;
2163 	int err, i;
2164 
2165 	sfp = sfp_alloc(&pdev->dev);
2166 	if (IS_ERR(sfp))
2167 		return PTR_ERR(sfp);
2168 
2169 	platform_set_drvdata(pdev, sfp);
2170 
2171 	err = devm_add_action(sfp->dev, sfp_cleanup, sfp);
2172 	if (err < 0)
2173 		return err;
2174 
2175 	sff = sfp->type = &sfp_data;
2176 
2177 	if (pdev->dev.of_node) {
2178 		struct device_node *node = pdev->dev.of_node;
2179 		const struct of_device_id *id;
2180 		struct device_node *np;
2181 
2182 		id = of_match_node(sfp_of_match, node);
2183 		if (WARN_ON(!id))
2184 			return -EINVAL;
2185 
2186 		sff = sfp->type = id->data;
2187 
2188 		np = of_parse_phandle(node, "i2c-bus", 0);
2189 		if (!np) {
2190 			dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2191 			return -ENODEV;
2192 		}
2193 
2194 		i2c = of_find_i2c_adapter_by_node(np);
2195 		of_node_put(np);
2196 	} else if (has_acpi_companion(&pdev->dev)) {
2197 		struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
2198 		struct fwnode_handle *fw = acpi_fwnode_handle(adev);
2199 		struct fwnode_reference_args args;
2200 		struct acpi_handle *acpi_handle;
2201 		int ret;
2202 
2203 		ret = acpi_node_get_property_reference(fw, "i2c-bus", 0, &args);
2204 		if (ret || !is_acpi_device_node(args.fwnode)) {
2205 			dev_err(&pdev->dev, "missing 'i2c-bus' property\n");
2206 			return -ENODEV;
2207 		}
2208 
2209 		acpi_handle = ACPI_HANDLE_FWNODE(args.fwnode);
2210 		i2c = i2c_acpi_find_adapter_by_handle(acpi_handle);
2211 	} else {
2212 		return -EINVAL;
2213 	}
2214 
2215 	if (!i2c)
2216 		return -EPROBE_DEFER;
2217 
2218 	err = sfp_i2c_configure(sfp, i2c);
2219 	if (err < 0) {
2220 		i2c_put_adapter(i2c);
2221 		return err;
2222 	}
2223 
2224 	for (i = 0; i < GPIO_MAX; i++)
2225 		if (sff->gpios & BIT(i)) {
2226 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
2227 					   gpio_of_names[i], gpio_flags[i]);
2228 			if (IS_ERR(sfp->gpio[i]))
2229 				return PTR_ERR(sfp->gpio[i]);
2230 		}
2231 
2232 	sfp->get_state = sfp_gpio_get_state;
2233 	sfp->set_state = sfp_gpio_set_state;
2234 
2235 	/* Modules that have no detect signal are always present */
2236 	if (!(sfp->gpio[GPIO_MODDEF0]))
2237 		sfp->get_state = sff_gpio_get_state;
2238 
2239 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
2240 				 &sfp->max_power_mW);
2241 	if (!sfp->max_power_mW)
2242 		sfp->max_power_mW = 1000;
2243 
2244 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
2245 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
2246 
2247 	/* Get the initial state, and always signal TX disable,
2248 	 * since the network interface will not be up.
2249 	 */
2250 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
2251 
2252 	if (sfp->gpio[GPIO_RATE_SELECT] &&
2253 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RATE_SELECT]))
2254 		sfp->state |= SFP_F_RATE_SELECT;
2255 	sfp_set_state(sfp, sfp->state);
2256 	sfp_module_tx_disable(sfp);
2257 	if (sfp->state & SFP_F_PRESENT) {
2258 		rtnl_lock();
2259 		sfp_sm_event(sfp, SFP_E_INSERT);
2260 		rtnl_unlock();
2261 	}
2262 
2263 	for (i = 0; i < GPIO_MAX; i++) {
2264 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
2265 			continue;
2266 
2267 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
2268 		if (!sfp->gpio_irq[i]) {
2269 			sfp->need_poll = true;
2270 			continue;
2271 		}
2272 
2273 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
2274 						NULL, sfp_irq,
2275 						IRQF_ONESHOT |
2276 						IRQF_TRIGGER_RISING |
2277 						IRQF_TRIGGER_FALLING,
2278 						dev_name(sfp->dev), sfp);
2279 		if (err) {
2280 			sfp->gpio_irq[i] = 0;
2281 			sfp->need_poll = true;
2282 		}
2283 	}
2284 
2285 	if (sfp->need_poll)
2286 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2287 
2288 	/* We could have an issue in cases no Tx disable pin is available or
2289 	 * wired as modules using a laser as their light source will continue to
2290 	 * be active when the fiber is removed. This could be a safety issue and
2291 	 * we should at least warn the user about that.
2292 	 */
2293 	if (!sfp->gpio[GPIO_TX_DISABLE])
2294 		dev_warn(sfp->dev,
2295 			 "No tx_disable pin: SFP modules will always be emitting.\n");
2296 
2297 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
2298 	if (!sfp->sfp_bus)
2299 		return -ENOMEM;
2300 
2301 	return 0;
2302 }
2303 
2304 static int sfp_remove(struct platform_device *pdev)
2305 {
2306 	struct sfp *sfp = platform_get_drvdata(pdev);
2307 
2308 	sfp_unregister_socket(sfp->sfp_bus);
2309 
2310 	rtnl_lock();
2311 	sfp_sm_event(sfp, SFP_E_REMOVE);
2312 	rtnl_unlock();
2313 
2314 	return 0;
2315 }
2316 
2317 static void sfp_shutdown(struct platform_device *pdev)
2318 {
2319 	struct sfp *sfp = platform_get_drvdata(pdev);
2320 	int i;
2321 
2322 	for (i = 0; i < GPIO_MAX; i++) {
2323 		if (!sfp->gpio_irq[i])
2324 			continue;
2325 
2326 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
2327 	}
2328 
2329 	cancel_delayed_work_sync(&sfp->poll);
2330 	cancel_delayed_work_sync(&sfp->timeout);
2331 }
2332 
2333 static struct platform_driver sfp_driver = {
2334 	.probe = sfp_probe,
2335 	.remove = sfp_remove,
2336 	.shutdown = sfp_shutdown,
2337 	.driver = {
2338 		.name = "sfp",
2339 		.of_match_table = sfp_of_match,
2340 	},
2341 };
2342 
2343 static int sfp_init(void)
2344 {
2345 	poll_jiffies = msecs_to_jiffies(100);
2346 
2347 	return platform_driver_register(&sfp_driver);
2348 }
2349 module_init(sfp_init);
2350 
2351 static void sfp_exit(void)
2352 {
2353 	platform_driver_unregister(&sfp_driver);
2354 }
2355 module_exit(sfp_exit);
2356 
2357 MODULE_ALIAS("platform:sfp");
2358 MODULE_AUTHOR("Russell King");
2359 MODULE_LICENSE("GPL v2");
2360