xref: /openbmc/linux/drivers/net/phy/sfp.c (revision 73f5e847)
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 #define T_WAIT		msecs_to_jiffies(50)
159 #define T_INIT_JIFFIES	msecs_to_jiffies(300)
160 #define T_RESET_US	10
161 #define T_FAULT_RECOVER	msecs_to_jiffies(1000)
162 
163 /* SFP module presence detection is poor: the three MOD DEF signals are
164  * the same length on the PCB, which means it's possible for MOD DEF 0 to
165  * connect before the I2C bus on MOD DEF 1/2.
166  *
167  * The SFF-8472 specifies t_serial ("Time from power on until module is
168  * ready for data transmission over the two wire serial bus.") as 300ms.
169  */
170 #define T_SERIAL	msecs_to_jiffies(300)
171 #define T_HPOWER_LEVEL	msecs_to_jiffies(300)
172 #define T_PROBE_RETRY	msecs_to_jiffies(100)
173 
174 /* SFP modules appear to always have their PHY configured for bus address
175  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
176  */
177 #define SFP_PHY_ADDR	22
178 
179 struct sff_data {
180 	unsigned int gpios;
181 	bool (*module_supported)(const struct sfp_eeprom_id *id);
182 };
183 
184 struct sfp {
185 	struct device *dev;
186 	struct i2c_adapter *i2c;
187 	struct mii_bus *i2c_mii;
188 	struct sfp_bus *sfp_bus;
189 	struct phy_device *mod_phy;
190 	const struct sff_data *type;
191 	u32 max_power_mW;
192 
193 	unsigned int (*get_state)(struct sfp *);
194 	void (*set_state)(struct sfp *, unsigned int);
195 	int (*read)(struct sfp *, bool, u8, void *, size_t);
196 	int (*write)(struct sfp *, bool, u8, void *, size_t);
197 
198 	struct gpio_desc *gpio[GPIO_MAX];
199 	int gpio_irq[GPIO_MAX];
200 
201 	struct mutex st_mutex;			/* Protects state */
202 	unsigned int state;
203 	struct delayed_work poll;
204 	struct delayed_work timeout;
205 	struct mutex sm_mutex;			/* Protects state machine */
206 	unsigned char sm_mod_state;
207 	unsigned char sm_dev_state;
208 	unsigned short sm_state;
209 	unsigned int sm_retries;
210 
211 	struct sfp_eeprom_id id;
212 	unsigned int module_power_mW;
213 
214 #if IS_ENABLED(CONFIG_HWMON)
215 	struct sfp_diag diag;
216 	struct device *hwmon_dev;
217 	char *hwmon_name;
218 #endif
219 
220 };
221 
222 static bool sff_module_supported(const struct sfp_eeprom_id *id)
223 {
224 	return id->base.phys_id == SFP_PHYS_ID_SFF &&
225 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
226 }
227 
228 static const struct sff_data sff_data = {
229 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
230 	.module_supported = sff_module_supported,
231 };
232 
233 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
234 {
235 	return id->base.phys_id == SFP_PHYS_ID_SFP &&
236 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
237 }
238 
239 static const struct sff_data sfp_data = {
240 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
241 		 SFP_F_TX_DISABLE | SFP_F_RATE_SELECT,
242 	.module_supported = sfp_module_supported,
243 };
244 
245 static const struct of_device_id sfp_of_match[] = {
246 	{ .compatible = "sff,sff", .data = &sff_data, },
247 	{ .compatible = "sff,sfp", .data = &sfp_data, },
248 	{ },
249 };
250 MODULE_DEVICE_TABLE(of, sfp_of_match);
251 
252 static unsigned long poll_jiffies;
253 
254 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
255 {
256 	unsigned int i, state, v;
257 
258 	for (i = state = 0; i < GPIO_MAX; i++) {
259 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
260 			continue;
261 
262 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
263 		if (v)
264 			state |= BIT(i);
265 	}
266 
267 	return state;
268 }
269 
270 static unsigned int sff_gpio_get_state(struct sfp *sfp)
271 {
272 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
273 }
274 
275 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
276 {
277 	if (state & SFP_F_PRESENT) {
278 		/* If the module is present, drive the signals */
279 		if (sfp->gpio[GPIO_TX_DISABLE])
280 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
281 					       state & SFP_F_TX_DISABLE);
282 		if (state & SFP_F_RATE_SELECT)
283 			gpiod_direction_output(sfp->gpio[GPIO_RATE_SELECT],
284 					       state & SFP_F_RATE_SELECT);
285 	} else {
286 		/* Otherwise, let them float to the pull-ups */
287 		if (sfp->gpio[GPIO_TX_DISABLE])
288 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
289 		if (state & SFP_F_RATE_SELECT)
290 			gpiod_direction_input(sfp->gpio[GPIO_RATE_SELECT]);
291 	}
292 }
293 
294 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
295 			size_t len)
296 {
297 	struct i2c_msg msgs[2];
298 	u8 bus_addr = a2 ? 0x51 : 0x50;
299 	size_t this_len;
300 	int ret;
301 
302 	msgs[0].addr = bus_addr;
303 	msgs[0].flags = 0;
304 	msgs[0].len = 1;
305 	msgs[0].buf = &dev_addr;
306 	msgs[1].addr = bus_addr;
307 	msgs[1].flags = I2C_M_RD;
308 	msgs[1].len = len;
309 	msgs[1].buf = buf;
310 
311 	while (len) {
312 		this_len = len;
313 		if (this_len > 16)
314 			this_len = 16;
315 
316 		msgs[1].len = this_len;
317 
318 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
319 		if (ret < 0)
320 			return ret;
321 
322 		if (ret != ARRAY_SIZE(msgs))
323 			break;
324 
325 		msgs[1].buf += this_len;
326 		dev_addr += this_len;
327 		len -= this_len;
328 	}
329 
330 	return msgs[1].buf - (u8 *)buf;
331 }
332 
333 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
334 	size_t len)
335 {
336 	struct i2c_msg msgs[1];
337 	u8 bus_addr = a2 ? 0x51 : 0x50;
338 	int ret;
339 
340 	msgs[0].addr = bus_addr;
341 	msgs[0].flags = 0;
342 	msgs[0].len = 1 + len;
343 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
344 	if (!msgs[0].buf)
345 		return -ENOMEM;
346 
347 	msgs[0].buf[0] = dev_addr;
348 	memcpy(&msgs[0].buf[1], buf, len);
349 
350 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
351 
352 	kfree(msgs[0].buf);
353 
354 	if (ret < 0)
355 		return ret;
356 
357 	return ret == ARRAY_SIZE(msgs) ? len : 0;
358 }
359 
360 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
361 {
362 	struct mii_bus *i2c_mii;
363 	int ret;
364 
365 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
366 		return -EINVAL;
367 
368 	sfp->i2c = i2c;
369 	sfp->read = sfp_i2c_read;
370 	sfp->write = sfp_i2c_write;
371 
372 	i2c_mii = mdio_i2c_alloc(sfp->dev, i2c);
373 	if (IS_ERR(i2c_mii))
374 		return PTR_ERR(i2c_mii);
375 
376 	i2c_mii->name = "SFP I2C Bus";
377 	i2c_mii->phy_mask = ~0;
378 
379 	ret = mdiobus_register(i2c_mii);
380 	if (ret < 0) {
381 		mdiobus_free(i2c_mii);
382 		return ret;
383 	}
384 
385 	sfp->i2c_mii = i2c_mii;
386 
387 	return 0;
388 }
389 
390 /* Interface */
391 static unsigned int sfp_get_state(struct sfp *sfp)
392 {
393 	return sfp->get_state(sfp);
394 }
395 
396 static void sfp_set_state(struct sfp *sfp, unsigned int state)
397 {
398 	sfp->set_state(sfp, state);
399 }
400 
401 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
402 {
403 	return sfp->read(sfp, a2, addr, buf, len);
404 }
405 
406 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
407 {
408 	return sfp->write(sfp, a2, addr, buf, len);
409 }
410 
411 static unsigned int sfp_check(void *buf, size_t len)
412 {
413 	u8 *p, check;
414 
415 	for (p = buf, check = 0; len; p++, len--)
416 		check += *p;
417 
418 	return check;
419 }
420 
421 /* hwmon */
422 #if IS_ENABLED(CONFIG_HWMON)
423 static umode_t sfp_hwmon_is_visible(const void *data,
424 				    enum hwmon_sensor_types type,
425 				    u32 attr, int channel)
426 {
427 	const struct sfp *sfp = data;
428 
429 	switch (type) {
430 	case hwmon_temp:
431 		switch (attr) {
432 		case hwmon_temp_min_alarm:
433 		case hwmon_temp_max_alarm:
434 		case hwmon_temp_lcrit_alarm:
435 		case hwmon_temp_crit_alarm:
436 		case hwmon_temp_min:
437 		case hwmon_temp_max:
438 		case hwmon_temp_lcrit:
439 		case hwmon_temp_crit:
440 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
441 				return 0;
442 			/* fall through */
443 		case hwmon_temp_input:
444 		case hwmon_temp_label:
445 			return 0444;
446 		default:
447 			return 0;
448 		}
449 	case hwmon_in:
450 		switch (attr) {
451 		case hwmon_in_min_alarm:
452 		case hwmon_in_max_alarm:
453 		case hwmon_in_lcrit_alarm:
454 		case hwmon_in_crit_alarm:
455 		case hwmon_in_min:
456 		case hwmon_in_max:
457 		case hwmon_in_lcrit:
458 		case hwmon_in_crit:
459 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
460 				return 0;
461 			/* fall through */
462 		case hwmon_in_input:
463 		case hwmon_in_label:
464 			return 0444;
465 		default:
466 			return 0;
467 		}
468 	case hwmon_curr:
469 		switch (attr) {
470 		case hwmon_curr_min_alarm:
471 		case hwmon_curr_max_alarm:
472 		case hwmon_curr_lcrit_alarm:
473 		case hwmon_curr_crit_alarm:
474 		case hwmon_curr_min:
475 		case hwmon_curr_max:
476 		case hwmon_curr_lcrit:
477 		case hwmon_curr_crit:
478 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
479 				return 0;
480 			/* fall through */
481 		case hwmon_curr_input:
482 		case hwmon_curr_label:
483 			return 0444;
484 		default:
485 			return 0;
486 		}
487 	case hwmon_power:
488 		/* External calibration of receive power requires
489 		 * floating point arithmetic. Doing that in the kernel
490 		 * is not easy, so just skip it. If the module does
491 		 * not require external calibration, we can however
492 		 * show receiver power, since FP is then not needed.
493 		 */
494 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
495 		    channel == 1)
496 			return 0;
497 		switch (attr) {
498 		case hwmon_power_min_alarm:
499 		case hwmon_power_max_alarm:
500 		case hwmon_power_lcrit_alarm:
501 		case hwmon_power_crit_alarm:
502 		case hwmon_power_min:
503 		case hwmon_power_max:
504 		case hwmon_power_lcrit:
505 		case hwmon_power_crit:
506 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
507 				return 0;
508 			/* fall through */
509 		case hwmon_power_input:
510 		case hwmon_power_label:
511 			return 0444;
512 		default:
513 			return 0;
514 		}
515 	default:
516 		return 0;
517 	}
518 }
519 
520 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
521 {
522 	__be16 val;
523 	int err;
524 
525 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
526 	if (err < 0)
527 		return err;
528 
529 	*value = be16_to_cpu(val);
530 
531 	return 0;
532 }
533 
534 static void sfp_hwmon_to_rx_power(long *value)
535 {
536 	*value = DIV_ROUND_CLOSEST(*value, 10);
537 }
538 
539 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
540 				long *value)
541 {
542 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
543 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
544 }
545 
546 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
547 {
548 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
549 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
550 
551 	if (*value >= 0x8000)
552 		*value -= 0x10000;
553 
554 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
555 }
556 
557 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
558 {
559 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
560 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
561 
562 	*value = DIV_ROUND_CLOSEST(*value, 10);
563 }
564 
565 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
566 {
567 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
568 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
569 
570 	*value = DIV_ROUND_CLOSEST(*value, 500);
571 }
572 
573 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
574 {
575 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
576 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
577 
578 	*value = DIV_ROUND_CLOSEST(*value, 10);
579 }
580 
581 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
582 {
583 	int err;
584 
585 	err = sfp_hwmon_read_sensor(sfp, reg, value);
586 	if (err < 0)
587 		return err;
588 
589 	sfp_hwmon_calibrate_temp(sfp, value);
590 
591 	return 0;
592 }
593 
594 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
595 {
596 	int err;
597 
598 	err = sfp_hwmon_read_sensor(sfp, reg, value);
599 	if (err < 0)
600 		return err;
601 
602 	sfp_hwmon_calibrate_vcc(sfp, value);
603 
604 	return 0;
605 }
606 
607 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
608 {
609 	int err;
610 
611 	err = sfp_hwmon_read_sensor(sfp, reg, value);
612 	if (err < 0)
613 		return err;
614 
615 	sfp_hwmon_calibrate_bias(sfp, value);
616 
617 	return 0;
618 }
619 
620 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
621 {
622 	int err;
623 
624 	err = sfp_hwmon_read_sensor(sfp, reg, value);
625 	if (err < 0)
626 		return err;
627 
628 	sfp_hwmon_calibrate_tx_power(sfp, value);
629 
630 	return 0;
631 }
632 
633 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
634 {
635 	int err;
636 
637 	err = sfp_hwmon_read_sensor(sfp, reg, value);
638 	if (err < 0)
639 		return err;
640 
641 	sfp_hwmon_to_rx_power(value);
642 
643 	return 0;
644 }
645 
646 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
647 {
648 	u8 status;
649 	int err;
650 
651 	switch (attr) {
652 	case hwmon_temp_input:
653 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
654 
655 	case hwmon_temp_lcrit:
656 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
657 		sfp_hwmon_calibrate_temp(sfp, value);
658 		return 0;
659 
660 	case hwmon_temp_min:
661 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
662 		sfp_hwmon_calibrate_temp(sfp, value);
663 		return 0;
664 	case hwmon_temp_max:
665 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
666 		sfp_hwmon_calibrate_temp(sfp, value);
667 		return 0;
668 
669 	case hwmon_temp_crit:
670 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
671 		sfp_hwmon_calibrate_temp(sfp, value);
672 		return 0;
673 
674 	case hwmon_temp_lcrit_alarm:
675 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
676 		if (err < 0)
677 			return err;
678 
679 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
680 		return 0;
681 
682 	case hwmon_temp_min_alarm:
683 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
684 		if (err < 0)
685 			return err;
686 
687 		*value = !!(status & SFP_WARN0_TEMP_LOW);
688 		return 0;
689 
690 	case hwmon_temp_max_alarm:
691 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
692 		if (err < 0)
693 			return err;
694 
695 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
696 		return 0;
697 
698 	case hwmon_temp_crit_alarm:
699 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
700 		if (err < 0)
701 			return err;
702 
703 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
704 		return 0;
705 	default:
706 		return -EOPNOTSUPP;
707 	}
708 
709 	return -EOPNOTSUPP;
710 }
711 
712 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
713 {
714 	u8 status;
715 	int err;
716 
717 	switch (attr) {
718 	case hwmon_in_input:
719 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
720 
721 	case hwmon_in_lcrit:
722 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
723 		sfp_hwmon_calibrate_vcc(sfp, value);
724 		return 0;
725 
726 	case hwmon_in_min:
727 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
728 		sfp_hwmon_calibrate_vcc(sfp, value);
729 		return 0;
730 
731 	case hwmon_in_max:
732 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
733 		sfp_hwmon_calibrate_vcc(sfp, value);
734 		return 0;
735 
736 	case hwmon_in_crit:
737 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
738 		sfp_hwmon_calibrate_vcc(sfp, value);
739 		return 0;
740 
741 	case hwmon_in_lcrit_alarm:
742 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
743 		if (err < 0)
744 			return err;
745 
746 		*value = !!(status & SFP_ALARM0_VCC_LOW);
747 		return 0;
748 
749 	case hwmon_in_min_alarm:
750 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
751 		if (err < 0)
752 			return err;
753 
754 		*value = !!(status & SFP_WARN0_VCC_LOW);
755 		return 0;
756 
757 	case hwmon_in_max_alarm:
758 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
759 		if (err < 0)
760 			return err;
761 
762 		*value = !!(status & SFP_WARN0_VCC_HIGH);
763 		return 0;
764 
765 	case hwmon_in_crit_alarm:
766 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
767 		if (err < 0)
768 			return err;
769 
770 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
771 		return 0;
772 	default:
773 		return -EOPNOTSUPP;
774 	}
775 
776 	return -EOPNOTSUPP;
777 }
778 
779 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
780 {
781 	u8 status;
782 	int err;
783 
784 	switch (attr) {
785 	case hwmon_curr_input:
786 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
787 
788 	case hwmon_curr_lcrit:
789 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
790 		sfp_hwmon_calibrate_bias(sfp, value);
791 		return 0;
792 
793 	case hwmon_curr_min:
794 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
795 		sfp_hwmon_calibrate_bias(sfp, value);
796 		return 0;
797 
798 	case hwmon_curr_max:
799 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
800 		sfp_hwmon_calibrate_bias(sfp, value);
801 		return 0;
802 
803 	case hwmon_curr_crit:
804 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
805 		sfp_hwmon_calibrate_bias(sfp, value);
806 		return 0;
807 
808 	case hwmon_curr_lcrit_alarm:
809 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
810 		if (err < 0)
811 			return err;
812 
813 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
814 		return 0;
815 
816 	case hwmon_curr_min_alarm:
817 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
818 		if (err < 0)
819 			return err;
820 
821 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
822 		return 0;
823 
824 	case hwmon_curr_max_alarm:
825 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
826 		if (err < 0)
827 			return err;
828 
829 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
830 		return 0;
831 
832 	case hwmon_curr_crit_alarm:
833 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
834 		if (err < 0)
835 			return err;
836 
837 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
838 		return 0;
839 	default:
840 		return -EOPNOTSUPP;
841 	}
842 
843 	return -EOPNOTSUPP;
844 }
845 
846 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
847 {
848 	u8 status;
849 	int err;
850 
851 	switch (attr) {
852 	case hwmon_power_input:
853 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
854 
855 	case hwmon_power_lcrit:
856 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
857 		sfp_hwmon_calibrate_tx_power(sfp, value);
858 		return 0;
859 
860 	case hwmon_power_min:
861 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
862 		sfp_hwmon_calibrate_tx_power(sfp, value);
863 		return 0;
864 
865 	case hwmon_power_max:
866 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
867 		sfp_hwmon_calibrate_tx_power(sfp, value);
868 		return 0;
869 
870 	case hwmon_power_crit:
871 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
872 		sfp_hwmon_calibrate_tx_power(sfp, value);
873 		return 0;
874 
875 	case hwmon_power_lcrit_alarm:
876 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
877 		if (err < 0)
878 			return err;
879 
880 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
881 		return 0;
882 
883 	case hwmon_power_min_alarm:
884 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
885 		if (err < 0)
886 			return err;
887 
888 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
889 		return 0;
890 
891 	case hwmon_power_max_alarm:
892 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
893 		if (err < 0)
894 			return err;
895 
896 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
897 		return 0;
898 
899 	case hwmon_power_crit_alarm:
900 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
901 		if (err < 0)
902 			return err;
903 
904 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
905 		return 0;
906 	default:
907 		return -EOPNOTSUPP;
908 	}
909 
910 	return -EOPNOTSUPP;
911 }
912 
913 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
914 {
915 	u8 status;
916 	int err;
917 
918 	switch (attr) {
919 	case hwmon_power_input:
920 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
921 
922 	case hwmon_power_lcrit:
923 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
924 		sfp_hwmon_to_rx_power(value);
925 		return 0;
926 
927 	case hwmon_power_min:
928 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
929 		sfp_hwmon_to_rx_power(value);
930 		return 0;
931 
932 	case hwmon_power_max:
933 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
934 		sfp_hwmon_to_rx_power(value);
935 		return 0;
936 
937 	case hwmon_power_crit:
938 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
939 		sfp_hwmon_to_rx_power(value);
940 		return 0;
941 
942 	case hwmon_power_lcrit_alarm:
943 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
944 		if (err < 0)
945 			return err;
946 
947 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
948 		return 0;
949 
950 	case hwmon_power_min_alarm:
951 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
952 		if (err < 0)
953 			return err;
954 
955 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
956 		return 0;
957 
958 	case hwmon_power_max_alarm:
959 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
960 		if (err < 0)
961 			return err;
962 
963 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
964 		return 0;
965 
966 	case hwmon_power_crit_alarm:
967 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
968 		if (err < 0)
969 			return err;
970 
971 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
972 		return 0;
973 	default:
974 		return -EOPNOTSUPP;
975 	}
976 
977 	return -EOPNOTSUPP;
978 }
979 
980 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
981 			  u32 attr, int channel, long *value)
982 {
983 	struct sfp *sfp = dev_get_drvdata(dev);
984 
985 	switch (type) {
986 	case hwmon_temp:
987 		return sfp_hwmon_temp(sfp, attr, value);
988 	case hwmon_in:
989 		return sfp_hwmon_vcc(sfp, attr, value);
990 	case hwmon_curr:
991 		return sfp_hwmon_bias(sfp, attr, value);
992 	case hwmon_power:
993 		switch (channel) {
994 		case 0:
995 			return sfp_hwmon_tx_power(sfp, attr, value);
996 		case 1:
997 			return sfp_hwmon_rx_power(sfp, attr, value);
998 		default:
999 			return -EOPNOTSUPP;
1000 		}
1001 	default:
1002 		return -EOPNOTSUPP;
1003 	}
1004 }
1005 
1006 static const char *const sfp_hwmon_power_labels[] = {
1007 	"TX_power",
1008 	"RX_power",
1009 };
1010 
1011 static int sfp_hwmon_read_string(struct device *dev,
1012 				 enum hwmon_sensor_types type,
1013 				 u32 attr, int channel, const char **str)
1014 {
1015 	switch (type) {
1016 	case hwmon_curr:
1017 		switch (attr) {
1018 		case hwmon_curr_label:
1019 			*str = "bias";
1020 			return 0;
1021 		default:
1022 			return -EOPNOTSUPP;
1023 		}
1024 		break;
1025 	case hwmon_temp:
1026 		switch (attr) {
1027 		case hwmon_temp_label:
1028 			*str = "temperature";
1029 			return 0;
1030 		default:
1031 			return -EOPNOTSUPP;
1032 		}
1033 		break;
1034 	case hwmon_in:
1035 		switch (attr) {
1036 		case hwmon_in_label:
1037 			*str = "VCC";
1038 			return 0;
1039 		default:
1040 			return -EOPNOTSUPP;
1041 		}
1042 		break;
1043 	case hwmon_power:
1044 		switch (attr) {
1045 		case hwmon_power_label:
1046 			*str = sfp_hwmon_power_labels[channel];
1047 			return 0;
1048 		default:
1049 			return -EOPNOTSUPP;
1050 		}
1051 		break;
1052 	default:
1053 		return -EOPNOTSUPP;
1054 	}
1055 
1056 	return -EOPNOTSUPP;
1057 }
1058 
1059 static const struct hwmon_ops sfp_hwmon_ops = {
1060 	.is_visible = sfp_hwmon_is_visible,
1061 	.read = sfp_hwmon_read,
1062 	.read_string = sfp_hwmon_read_string,
1063 };
1064 
1065 static u32 sfp_hwmon_chip_config[] = {
1066 	HWMON_C_REGISTER_TZ,
1067 	0,
1068 };
1069 
1070 static const struct hwmon_channel_info sfp_hwmon_chip = {
1071 	.type = hwmon_chip,
1072 	.config = sfp_hwmon_chip_config,
1073 };
1074 
1075 static u32 sfp_hwmon_temp_config[] = {
1076 	HWMON_T_INPUT |
1077 	HWMON_T_MAX | HWMON_T_MIN |
1078 	HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1079 	HWMON_T_CRIT | HWMON_T_LCRIT |
1080 	HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1081 	HWMON_T_LABEL,
1082 	0,
1083 };
1084 
1085 static const struct hwmon_channel_info sfp_hwmon_temp_channel_info = {
1086 	.type = hwmon_temp,
1087 	.config = sfp_hwmon_temp_config,
1088 };
1089 
1090 static u32 sfp_hwmon_vcc_config[] = {
1091 	HWMON_I_INPUT |
1092 	HWMON_I_MAX | HWMON_I_MIN |
1093 	HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1094 	HWMON_I_CRIT | HWMON_I_LCRIT |
1095 	HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1096 	HWMON_I_LABEL,
1097 	0,
1098 };
1099 
1100 static const struct hwmon_channel_info sfp_hwmon_vcc_channel_info = {
1101 	.type = hwmon_in,
1102 	.config = sfp_hwmon_vcc_config,
1103 };
1104 
1105 static u32 sfp_hwmon_bias_config[] = {
1106 	HWMON_C_INPUT |
1107 	HWMON_C_MAX | HWMON_C_MIN |
1108 	HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1109 	HWMON_C_CRIT | HWMON_C_LCRIT |
1110 	HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1111 	HWMON_C_LABEL,
1112 	0,
1113 };
1114 
1115 static const struct hwmon_channel_info sfp_hwmon_bias_channel_info = {
1116 	.type = hwmon_curr,
1117 	.config = sfp_hwmon_bias_config,
1118 };
1119 
1120 static u32 sfp_hwmon_power_config[] = {
1121 	/* Transmit power */
1122 	HWMON_P_INPUT |
1123 	HWMON_P_MAX | HWMON_P_MIN |
1124 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1125 	HWMON_P_CRIT | HWMON_P_LCRIT |
1126 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1127 	HWMON_P_LABEL,
1128 	/* Receive power */
1129 	HWMON_P_INPUT |
1130 	HWMON_P_MAX | HWMON_P_MIN |
1131 	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1132 	HWMON_P_CRIT | HWMON_P_LCRIT |
1133 	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1134 	HWMON_P_LABEL,
1135 	0,
1136 };
1137 
1138 static const struct hwmon_channel_info sfp_hwmon_power_channel_info = {
1139 	.type = hwmon_power,
1140 	.config = sfp_hwmon_power_config,
1141 };
1142 
1143 static const struct hwmon_channel_info *sfp_hwmon_info[] = {
1144 	&sfp_hwmon_chip,
1145 	&sfp_hwmon_vcc_channel_info,
1146 	&sfp_hwmon_temp_channel_info,
1147 	&sfp_hwmon_bias_channel_info,
1148 	&sfp_hwmon_power_channel_info,
1149 	NULL,
1150 };
1151 
1152 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1153 	.ops = &sfp_hwmon_ops,
1154 	.info = sfp_hwmon_info,
1155 };
1156 
1157 static int sfp_hwmon_insert(struct sfp *sfp)
1158 {
1159 	int err, i;
1160 
1161 	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
1162 		return 0;
1163 
1164 	if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
1165 		return 0;
1166 
1167 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1168 		/* This driver in general does not support address
1169 		 * change.
1170 		 */
1171 		return 0;
1172 
1173 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1174 	if (err < 0)
1175 		return err;
1176 
1177 	sfp->hwmon_name = kstrdup(dev_name(sfp->dev), GFP_KERNEL);
1178 	if (!sfp->hwmon_name)
1179 		return -ENODEV;
1180 
1181 	for (i = 0; sfp->hwmon_name[i]; i++)
1182 		if (hwmon_is_bad_char(sfp->hwmon_name[i]))
1183 			sfp->hwmon_name[i] = '_';
1184 
1185 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1186 							 sfp->hwmon_name, sfp,
1187 							 &sfp_hwmon_chip_info,
1188 							 NULL);
1189 
1190 	return PTR_ERR_OR_ZERO(sfp->hwmon_dev);
1191 }
1192 
1193 static void sfp_hwmon_remove(struct sfp *sfp)
1194 {
1195 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1196 		hwmon_device_unregister(sfp->hwmon_dev);
1197 		sfp->hwmon_dev = NULL;
1198 		kfree(sfp->hwmon_name);
1199 	}
1200 }
1201 #else
1202 static int sfp_hwmon_insert(struct sfp *sfp)
1203 {
1204 	return 0;
1205 }
1206 
1207 static void sfp_hwmon_remove(struct sfp *sfp)
1208 {
1209 }
1210 #endif
1211 
1212 /* Helpers */
1213 static void sfp_module_tx_disable(struct sfp *sfp)
1214 {
1215 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1216 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1217 	sfp->state |= SFP_F_TX_DISABLE;
1218 	sfp_set_state(sfp, sfp->state);
1219 }
1220 
1221 static void sfp_module_tx_enable(struct sfp *sfp)
1222 {
1223 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1224 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1225 	sfp->state &= ~SFP_F_TX_DISABLE;
1226 	sfp_set_state(sfp, sfp->state);
1227 }
1228 
1229 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1230 {
1231 	unsigned int state = sfp->state;
1232 
1233 	if (state & SFP_F_TX_DISABLE)
1234 		return;
1235 
1236 	sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1237 
1238 	udelay(T_RESET_US);
1239 
1240 	sfp_set_state(sfp, state);
1241 }
1242 
1243 /* SFP state machine */
1244 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1245 {
1246 	if (timeout)
1247 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1248 				 timeout);
1249 	else
1250 		cancel_delayed_work(&sfp->timeout);
1251 }
1252 
1253 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1254 			unsigned int timeout)
1255 {
1256 	sfp->sm_state = state;
1257 	sfp_sm_set_timer(sfp, timeout);
1258 }
1259 
1260 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1261 			    unsigned int timeout)
1262 {
1263 	sfp->sm_mod_state = state;
1264 	sfp_sm_set_timer(sfp, timeout);
1265 }
1266 
1267 static void sfp_sm_phy_detach(struct sfp *sfp)
1268 {
1269 	phy_stop(sfp->mod_phy);
1270 	sfp_remove_phy(sfp->sfp_bus);
1271 	phy_device_remove(sfp->mod_phy);
1272 	phy_device_free(sfp->mod_phy);
1273 	sfp->mod_phy = NULL;
1274 }
1275 
1276 static void sfp_sm_probe_phy(struct sfp *sfp)
1277 {
1278 	struct phy_device *phy;
1279 	int err;
1280 
1281 	phy = mdiobus_scan(sfp->i2c_mii, SFP_PHY_ADDR);
1282 	if (phy == ERR_PTR(-ENODEV)) {
1283 		dev_info(sfp->dev, "no PHY detected\n");
1284 		return;
1285 	}
1286 	if (IS_ERR(phy)) {
1287 		dev_err(sfp->dev, "mdiobus scan returned %ld\n", PTR_ERR(phy));
1288 		return;
1289 	}
1290 
1291 	err = sfp_add_phy(sfp->sfp_bus, phy);
1292 	if (err) {
1293 		phy_device_remove(phy);
1294 		phy_device_free(phy);
1295 		dev_err(sfp->dev, "sfp_add_phy failed: %d\n", err);
1296 		return;
1297 	}
1298 
1299 	sfp->mod_phy = phy;
1300 	phy_start(phy);
1301 }
1302 
1303 static void sfp_sm_link_up(struct sfp *sfp)
1304 {
1305 	sfp_link_up(sfp->sfp_bus);
1306 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1307 }
1308 
1309 static void sfp_sm_link_down(struct sfp *sfp)
1310 {
1311 	sfp_link_down(sfp->sfp_bus);
1312 }
1313 
1314 static void sfp_sm_link_check_los(struct sfp *sfp)
1315 {
1316 	unsigned int los = sfp->state & SFP_F_LOS;
1317 
1318 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1319 	 * are set, we assume that no LOS signal is available.
1320 	 */
1321 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED))
1322 		los ^= SFP_F_LOS;
1323 	else if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL)))
1324 		los = 0;
1325 
1326 	if (los)
1327 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1328 	else
1329 		sfp_sm_link_up(sfp);
1330 }
1331 
1332 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1333 {
1334 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1335 		event == SFP_E_LOS_LOW) ||
1336 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1337 		event == SFP_E_LOS_HIGH);
1338 }
1339 
1340 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1341 {
1342 	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
1343 		event == SFP_E_LOS_HIGH) ||
1344 	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
1345 		event == SFP_E_LOS_LOW);
1346 }
1347 
1348 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1349 {
1350 	if (sfp->sm_retries && !--sfp->sm_retries) {
1351 		dev_err(sfp->dev,
1352 			"module persistently indicates fault, disabling\n");
1353 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1354 	} else {
1355 		if (warn)
1356 			dev_err(sfp->dev, "module transmit fault indicated\n");
1357 
1358 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1359 	}
1360 }
1361 
1362 static void sfp_sm_mod_init(struct sfp *sfp)
1363 {
1364 	sfp_module_tx_enable(sfp);
1365 }
1366 
1367 static void sfp_sm_probe_for_phy(struct sfp *sfp)
1368 {
1369 	/* Setting the serdes link mode is guesswork: there's no
1370 	 * field in the EEPROM which indicates what mode should
1371 	 * be used.
1372 	 *
1373 	 * If it's a gigabit-only fiber module, it probably does
1374 	 * not have a PHY, so switch to 802.3z negotiation mode.
1375 	 * Otherwise, switch to SGMII mode (which is required to
1376 	 * support non-gigabit speeds) and probe for a PHY.
1377 	 */
1378 	if (sfp->id.base.e1000_base_t ||
1379 	    sfp->id.base.e100_base_lx ||
1380 	    sfp->id.base.e100_base_fx)
1381 		sfp_sm_probe_phy(sfp);
1382 }
1383 
1384 static int sfp_module_parse_power(struct sfp *sfp)
1385 {
1386 	u32 power_mW = 1000;
1387 
1388 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1389 		power_mW = 1500;
1390 	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1391 		power_mW = 2000;
1392 
1393 	if (power_mW > sfp->max_power_mW) {
1394 		/* Module power specification exceeds the allowed maximum. */
1395 		if (sfp->id.ext.sff8472_compliance ==
1396 			SFP_SFF8472_COMPLIANCE_NONE &&
1397 		    !(sfp->id.ext.diagmon & SFP_DIAGMON_DDM)) {
1398 			/* The module appears not to implement bus address
1399 			 * 0xa2, so assume that the module powers up in the
1400 			 * indicated mode.
1401 			 */
1402 			dev_err(sfp->dev,
1403 				"Host does not support %u.%uW modules\n",
1404 				power_mW / 1000, (power_mW / 100) % 10);
1405 			return -EINVAL;
1406 		} else {
1407 			dev_warn(sfp->dev,
1408 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1409 				 power_mW / 1000, (power_mW / 100) % 10);
1410 			return 0;
1411 		}
1412 	}
1413 
1414 	/* If the module requires a higher power mode, but also requires
1415 	 * an address change sequence, warn the user that the module may
1416 	 * not be functional.
1417 	 */
1418 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE && power_mW > 1000) {
1419 		dev_warn(sfp->dev,
1420 			 "Address Change Sequence not supported but module requies %u.%uW, module may not be functional\n",
1421 			 power_mW / 1000, (power_mW / 100) % 10);
1422 		return 0;
1423 	}
1424 
1425 	sfp->module_power_mW = power_mW;
1426 
1427 	return 0;
1428 }
1429 
1430 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1431 {
1432 	u8 val;
1433 	int err;
1434 
1435 	err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1436 	if (err != sizeof(val)) {
1437 		dev_err(sfp->dev, "Failed to read EEPROM: %d\n", err);
1438 		return -EAGAIN;
1439 	}
1440 
1441 	if (enable)
1442 		val |= BIT(0);
1443 	else
1444 		val &= ~BIT(0);
1445 
1446 	err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
1447 	if (err != sizeof(val)) {
1448 		dev_err(sfp->dev, "Failed to write EEPROM: %d\n", err);
1449 		return -EAGAIN;
1450 	}
1451 
1452 	if (enable)
1453 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1454 			 sfp->module_power_mW / 1000,
1455 			 (sfp->module_power_mW / 100) % 10);
1456 
1457 	return 0;
1458 }
1459 
1460 static int sfp_sm_mod_probe(struct sfp *sfp)
1461 {
1462 	/* SFP module inserted - read I2C data */
1463 	struct sfp_eeprom_id id;
1464 	bool cotsworks;
1465 	u8 check;
1466 	int ret;
1467 
1468 	ret = sfp_read(sfp, false, 0, &id, sizeof(id));
1469 	if (ret < 0) {
1470 		dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
1471 		return -EAGAIN;
1472 	}
1473 
1474 	if (ret != sizeof(id)) {
1475 		dev_err(sfp->dev, "EEPROM short read: %d\n", ret);
1476 		return -EAGAIN;
1477 	}
1478 
1479 	/* Cotsworks do not seem to update the checksums when they
1480 	 * do the final programming with the final module part number,
1481 	 * serial number and date code.
1482 	 */
1483 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
1484 
1485 	/* Validate the checksum over the base structure */
1486 	check = sfp_check(&id.base, sizeof(id.base) - 1);
1487 	if (check != id.base.cc_base) {
1488 		if (cotsworks) {
1489 			dev_warn(sfp->dev,
1490 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
1491 				 check, id.base.cc_base);
1492 		} else {
1493 			dev_err(sfp->dev,
1494 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
1495 				check, id.base.cc_base);
1496 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1497 				       16, 1, &id, sizeof(id), true);
1498 			return -EINVAL;
1499 		}
1500 	}
1501 
1502 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
1503 	if (check != id.ext.cc_ext) {
1504 		if (cotsworks) {
1505 			dev_warn(sfp->dev,
1506 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
1507 				 check, id.ext.cc_ext);
1508 		} else {
1509 			dev_err(sfp->dev,
1510 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
1511 				check, id.ext.cc_ext);
1512 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
1513 				       16, 1, &id, sizeof(id), true);
1514 			memset(&id.ext, 0, sizeof(id.ext));
1515 		}
1516 	}
1517 
1518 	sfp->id = id;
1519 
1520 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
1521 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
1522 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
1523 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
1524 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
1525 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
1526 
1527 	/* Check whether we support this module */
1528 	if (!sfp->type->module_supported(&sfp->id)) {
1529 		dev_err(sfp->dev,
1530 			"module is not supported - phys id 0x%02x 0x%02x\n",
1531 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
1532 		return -EINVAL;
1533 	}
1534 
1535 	/* If the module requires address swap mode, warn about it */
1536 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1537 		dev_warn(sfp->dev,
1538 			 "module address swap to access page 0xA2 is not supported.\n");
1539 
1540 	/* Parse the module power requirement */
1541 	ret = sfp_module_parse_power(sfp);
1542 	if (ret < 0)
1543 		return ret;
1544 
1545 	ret = sfp_hwmon_insert(sfp);
1546 	if (ret < 0)
1547 		return ret;
1548 
1549 	return 0;
1550 }
1551 
1552 static void sfp_sm_mod_remove(struct sfp *sfp)
1553 {
1554 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
1555 		sfp_module_remove(sfp->sfp_bus);
1556 
1557 	sfp_hwmon_remove(sfp);
1558 
1559 	memset(&sfp->id, 0, sizeof(sfp->id));
1560 	sfp->module_power_mW = 0;
1561 
1562 	dev_info(sfp->dev, "module removed\n");
1563 }
1564 
1565 /* This state machine tracks the upstream's state */
1566 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
1567 {
1568 	switch (sfp->sm_dev_state) {
1569 	default:
1570 		if (event == SFP_E_DEV_ATTACH)
1571 			sfp->sm_dev_state = SFP_DEV_DOWN;
1572 		break;
1573 
1574 	case SFP_DEV_DOWN:
1575 		if (event == SFP_E_DEV_DETACH)
1576 			sfp->sm_dev_state = SFP_DEV_DETACHED;
1577 		else if (event == SFP_E_DEV_UP)
1578 			sfp->sm_dev_state = SFP_DEV_UP;
1579 		break;
1580 
1581 	case SFP_DEV_UP:
1582 		if (event == SFP_E_DEV_DETACH)
1583 			sfp->sm_dev_state = SFP_DEV_DETACHED;
1584 		else if (event == SFP_E_DEV_DOWN)
1585 			sfp->sm_dev_state = SFP_DEV_DOWN;
1586 		break;
1587 	}
1588 }
1589 
1590 /* This state machine tracks the insert/remove state of the module, probes
1591  * the on-board EEPROM, and sets up the power level.
1592  */
1593 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
1594 {
1595 	int err;
1596 
1597 	/* Handle remove event globally, it resets this state machine */
1598 	if (event == SFP_E_REMOVE) {
1599 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
1600 			sfp_sm_mod_remove(sfp);
1601 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
1602 		return;
1603 	}
1604 
1605 	/* Handle device detach globally */
1606 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
1607 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
1608 		if (sfp->module_power_mW > 1000 &&
1609 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
1610 			sfp_sm_mod_hpower(sfp, false);
1611 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
1612 		return;
1613 	}
1614 
1615 	switch (sfp->sm_mod_state) {
1616 	default:
1617 		if (event == SFP_E_INSERT)
1618 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
1619 		break;
1620 
1621 	case SFP_MOD_PROBE:
1622 		/* Wait for T_PROBE_INIT to time out */
1623 		if (event != SFP_E_TIMEOUT)
1624 			break;
1625 
1626 		err = sfp_sm_mod_probe(sfp);
1627 		if (err == -EAGAIN) {
1628 			sfp_sm_set_timer(sfp, T_PROBE_RETRY);
1629 			break;
1630 		}
1631 		if (err < 0) {
1632 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1633 			break;
1634 		}
1635 
1636 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
1637 		/* fall through */
1638 	case SFP_MOD_WAITDEV:
1639 		/* Ensure that the device is attached before proceeding */
1640 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
1641 			break;
1642 
1643 		/* Report the module insertion to the upstream device */
1644 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id);
1645 		if (err < 0) {
1646 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1647 			break;
1648 		}
1649 
1650 		/* If this is a power level 1 module, we are done */
1651 		if (sfp->module_power_mW <= 1000)
1652 			goto insert;
1653 
1654 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
1655 		/* fall through */
1656 	case SFP_MOD_HPOWER:
1657 		/* Enable high power mode */
1658 		err = sfp_sm_mod_hpower(sfp, true);
1659 		if (err < 0) {
1660 			if (err != -EAGAIN) {
1661 				sfp_module_remove(sfp->sfp_bus);
1662 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
1663 			} else {
1664 				sfp_sm_set_timer(sfp, T_PROBE_RETRY);
1665 			}
1666 			break;
1667 		}
1668 
1669 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
1670 		break;
1671 
1672 	case SFP_MOD_WAITPWR:
1673 		/* Wait for T_HPOWER_LEVEL to time out */
1674 		if (event != SFP_E_TIMEOUT)
1675 			break;
1676 
1677 	insert:
1678 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
1679 		break;
1680 
1681 	case SFP_MOD_PRESENT:
1682 	case SFP_MOD_ERROR:
1683 		break;
1684 	}
1685 }
1686 
1687 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
1688 {
1689 	unsigned long timeout;
1690 
1691 	/* Some events are global */
1692 	if (sfp->sm_state != SFP_S_DOWN &&
1693 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
1694 	     sfp->sm_dev_state != SFP_DEV_UP)) {
1695 		if (sfp->sm_state == SFP_S_LINK_UP &&
1696 		    sfp->sm_dev_state == SFP_DEV_UP)
1697 			sfp_sm_link_down(sfp);
1698 		if (sfp->mod_phy)
1699 			sfp_sm_phy_detach(sfp);
1700 		sfp_module_tx_disable(sfp);
1701 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
1702 		return;
1703 	}
1704 
1705 	/* The main state machine */
1706 	switch (sfp->sm_state) {
1707 	case SFP_S_DOWN:
1708 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
1709 		    sfp->sm_dev_state != SFP_DEV_UP)
1710 			break;
1711 
1712 		sfp_sm_mod_init(sfp);
1713 
1714 		/* Initialise the fault clearance retries */
1715 		sfp->sm_retries = 5;
1716 
1717 		/* We need to check the TX_FAULT state, which is not defined
1718 		 * while TX_DISABLE is asserted. The earliest we want to do
1719 		 * anything (such as probe for a PHY) is 50ms.
1720 		 */
1721 		sfp_sm_next(sfp, SFP_S_WAIT, T_WAIT);
1722 		break;
1723 
1724 	case SFP_S_WAIT:
1725 		if (event != SFP_E_TIMEOUT)
1726 			break;
1727 
1728 		if (sfp->state & SFP_F_TX_FAULT) {
1729 			/* Wait t_init before indicating that the link is up,
1730 			 * provided the current state indicates no TX_FAULT. If
1731 			 * TX_FAULT clears before this time, that's fine too.
1732 			 */
1733 			timeout = T_INIT_JIFFIES;
1734 			if (timeout > T_WAIT)
1735 				timeout -= T_WAIT;
1736 			else
1737 				timeout = 1;
1738 
1739 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
1740 		} else {
1741 			/* TX_FAULT is not asserted, assume the module has
1742 			 * finished initialising.
1743 			 */
1744 			goto init_done;
1745 		}
1746 		break;
1747 
1748 	case SFP_S_INIT:
1749 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
1750 			/* TX_FAULT is still asserted after t_init, so assume
1751 			 * there is a fault.
1752 			 */
1753 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
1754 				     sfp->sm_retries == 5);
1755 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
1756 	init_done:	/* TX_FAULT deasserted or we timed out with TX_FAULT
1757 			 * clear.  Probe for the PHY and check the LOS state.
1758 			 */
1759 			sfp_sm_probe_for_phy(sfp);
1760 			sfp_sm_link_check_los(sfp);
1761 
1762 			/* Reset the fault retry count */
1763 			sfp->sm_retries = 5;
1764 		}
1765 		break;
1766 
1767 	case SFP_S_INIT_TX_FAULT:
1768 		if (event == SFP_E_TIMEOUT) {
1769 			sfp_module_tx_fault_reset(sfp);
1770 			sfp_sm_next(sfp, SFP_S_INIT, T_INIT_JIFFIES);
1771 		}
1772 		break;
1773 
1774 	case SFP_S_WAIT_LOS:
1775 		if (event == SFP_E_TX_FAULT)
1776 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
1777 		else if (sfp_los_event_inactive(sfp, event))
1778 			sfp_sm_link_up(sfp);
1779 		break;
1780 
1781 	case SFP_S_LINK_UP:
1782 		if (event == SFP_E_TX_FAULT) {
1783 			sfp_sm_link_down(sfp);
1784 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
1785 		} else if (sfp_los_event_active(sfp, event)) {
1786 			sfp_sm_link_down(sfp);
1787 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1788 		}
1789 		break;
1790 
1791 	case SFP_S_TX_FAULT:
1792 		if (event == SFP_E_TIMEOUT) {
1793 			sfp_module_tx_fault_reset(sfp);
1794 			sfp_sm_next(sfp, SFP_S_REINIT, T_INIT_JIFFIES);
1795 		}
1796 		break;
1797 
1798 	case SFP_S_REINIT:
1799 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
1800 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
1801 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
1802 			dev_info(sfp->dev, "module transmit fault recovered\n");
1803 			sfp_sm_link_check_los(sfp);
1804 		}
1805 		break;
1806 
1807 	case SFP_S_TX_DISABLE:
1808 		break;
1809 	}
1810 }
1811 
1812 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
1813 {
1814 	mutex_lock(&sfp->sm_mutex);
1815 
1816 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
1817 		mod_state_to_str(sfp->sm_mod_state),
1818 		dev_state_to_str(sfp->sm_dev_state),
1819 		sm_state_to_str(sfp->sm_state),
1820 		event_to_str(event));
1821 
1822 	sfp_sm_device(sfp, event);
1823 	sfp_sm_module(sfp, event);
1824 	sfp_sm_main(sfp, event);
1825 
1826 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
1827 		mod_state_to_str(sfp->sm_mod_state),
1828 		dev_state_to_str(sfp->sm_dev_state),
1829 		sm_state_to_str(sfp->sm_state));
1830 
1831 	mutex_unlock(&sfp->sm_mutex);
1832 }
1833 
1834 static void sfp_attach(struct sfp *sfp)
1835 {
1836 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
1837 }
1838 
1839 static void sfp_detach(struct sfp *sfp)
1840 {
1841 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
1842 }
1843 
1844 static void sfp_start(struct sfp *sfp)
1845 {
1846 	sfp_sm_event(sfp, SFP_E_DEV_UP);
1847 }
1848 
1849 static void sfp_stop(struct sfp *sfp)
1850 {
1851 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
1852 }
1853 
1854 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
1855 {
1856 	/* locking... and check module is present */
1857 
1858 	if (sfp->id.ext.sff8472_compliance &&
1859 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
1860 		modinfo->type = ETH_MODULE_SFF_8472;
1861 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
1862 	} else {
1863 		modinfo->type = ETH_MODULE_SFF_8079;
1864 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
1865 	}
1866 	return 0;
1867 }
1868 
1869 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
1870 			     u8 *data)
1871 {
1872 	unsigned int first, last, len;
1873 	int ret;
1874 
1875 	if (ee->len == 0)
1876 		return -EINVAL;
1877 
1878 	first = ee->offset;
1879 	last = ee->offset + ee->len;
1880 	if (first < ETH_MODULE_SFF_8079_LEN) {
1881 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
1882 		len -= first;
1883 
1884 		ret = sfp_read(sfp, false, first, data, len);
1885 		if (ret < 0)
1886 			return ret;
1887 
1888 		first += len;
1889 		data += len;
1890 	}
1891 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
1892 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
1893 		len -= first;
1894 		first -= ETH_MODULE_SFF_8079_LEN;
1895 
1896 		ret = sfp_read(sfp, true, first, data, len);
1897 		if (ret < 0)
1898 			return ret;
1899 	}
1900 	return 0;
1901 }
1902 
1903 static const struct sfp_socket_ops sfp_module_ops = {
1904 	.attach = sfp_attach,
1905 	.detach = sfp_detach,
1906 	.start = sfp_start,
1907 	.stop = sfp_stop,
1908 	.module_info = sfp_module_info,
1909 	.module_eeprom = sfp_module_eeprom,
1910 };
1911 
1912 static void sfp_timeout(struct work_struct *work)
1913 {
1914 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
1915 
1916 	rtnl_lock();
1917 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
1918 	rtnl_unlock();
1919 }
1920 
1921 static void sfp_check_state(struct sfp *sfp)
1922 {
1923 	unsigned int state, i, changed;
1924 
1925 	mutex_lock(&sfp->st_mutex);
1926 	state = sfp_get_state(sfp);
1927 	changed = state ^ sfp->state;
1928 	changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
1929 
1930 	for (i = 0; i < GPIO_MAX; i++)
1931 		if (changed & BIT(i))
1932 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_of_names[i],
1933 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
1934 
1935 	state |= sfp->state & (SFP_F_TX_DISABLE | SFP_F_RATE_SELECT);
1936 	sfp->state = state;
1937 
1938 	rtnl_lock();
1939 	if (changed & SFP_F_PRESENT)
1940 		sfp_sm_event(sfp, state & SFP_F_PRESENT ?
1941 				SFP_E_INSERT : SFP_E_REMOVE);
1942 
1943 	if (changed & SFP_F_TX_FAULT)
1944 		sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
1945 				SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
1946 
1947 	if (changed & SFP_F_LOS)
1948 		sfp_sm_event(sfp, state & SFP_F_LOS ?
1949 				SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
1950 	rtnl_unlock();
1951 	mutex_unlock(&sfp->st_mutex);
1952 }
1953 
1954 static irqreturn_t sfp_irq(int irq, void *data)
1955 {
1956 	struct sfp *sfp = data;
1957 
1958 	sfp_check_state(sfp);
1959 
1960 	return IRQ_HANDLED;
1961 }
1962 
1963 static void sfp_poll(struct work_struct *work)
1964 {
1965 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
1966 
1967 	sfp_check_state(sfp);
1968 	mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
1969 }
1970 
1971 static struct sfp *sfp_alloc(struct device *dev)
1972 {
1973 	struct sfp *sfp;
1974 
1975 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
1976 	if (!sfp)
1977 		return ERR_PTR(-ENOMEM);
1978 
1979 	sfp->dev = dev;
1980 
1981 	mutex_init(&sfp->sm_mutex);
1982 	mutex_init(&sfp->st_mutex);
1983 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
1984 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
1985 
1986 	return sfp;
1987 }
1988 
1989 static void sfp_cleanup(void *data)
1990 {
1991 	struct sfp *sfp = data;
1992 
1993 	cancel_delayed_work_sync(&sfp->poll);
1994 	cancel_delayed_work_sync(&sfp->timeout);
1995 	if (sfp->i2c_mii) {
1996 		mdiobus_unregister(sfp->i2c_mii);
1997 		mdiobus_free(sfp->i2c_mii);
1998 	}
1999 	if (sfp->i2c)
2000 		i2c_put_adapter(sfp->i2c);
2001 	kfree(sfp);
2002 }
2003 
2004 static int sfp_probe(struct platform_device *pdev)
2005 {
2006 	const struct sff_data *sff;
2007 	struct i2c_adapter *i2c;
2008 	struct sfp *sfp;
2009 	bool poll = false;
2010 	int err, i;
2011 
2012 	sfp = sfp_alloc(&pdev->dev);
2013 	if (IS_ERR(sfp))
2014 		return PTR_ERR(sfp);
2015 
2016 	platform_set_drvdata(pdev, sfp);
2017 
2018 	err = devm_add_action(sfp->dev, sfp_cleanup, sfp);
2019 	if (err < 0)
2020 		return err;
2021 
2022 	sff = sfp->type = &sfp_data;
2023 
2024 	if (pdev->dev.of_node) {
2025 		struct device_node *node = pdev->dev.of_node;
2026 		const struct of_device_id *id;
2027 		struct device_node *np;
2028 
2029 		id = of_match_node(sfp_of_match, node);
2030 		if (WARN_ON(!id))
2031 			return -EINVAL;
2032 
2033 		sff = sfp->type = id->data;
2034 
2035 		np = of_parse_phandle(node, "i2c-bus", 0);
2036 		if (!np) {
2037 			dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2038 			return -ENODEV;
2039 		}
2040 
2041 		i2c = of_find_i2c_adapter_by_node(np);
2042 		of_node_put(np);
2043 	} else if (has_acpi_companion(&pdev->dev)) {
2044 		struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
2045 		struct fwnode_handle *fw = acpi_fwnode_handle(adev);
2046 		struct fwnode_reference_args args;
2047 		struct acpi_handle *acpi_handle;
2048 		int ret;
2049 
2050 		ret = acpi_node_get_property_reference(fw, "i2c-bus", 0, &args);
2051 		if (ret || !is_acpi_device_node(args.fwnode)) {
2052 			dev_err(&pdev->dev, "missing 'i2c-bus' property\n");
2053 			return -ENODEV;
2054 		}
2055 
2056 		acpi_handle = ACPI_HANDLE_FWNODE(args.fwnode);
2057 		i2c = i2c_acpi_find_adapter_by_handle(acpi_handle);
2058 	} else {
2059 		return -EINVAL;
2060 	}
2061 
2062 	if (!i2c)
2063 		return -EPROBE_DEFER;
2064 
2065 	err = sfp_i2c_configure(sfp, i2c);
2066 	if (err < 0) {
2067 		i2c_put_adapter(i2c);
2068 		return err;
2069 	}
2070 
2071 	for (i = 0; i < GPIO_MAX; i++)
2072 		if (sff->gpios & BIT(i)) {
2073 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
2074 					   gpio_of_names[i], gpio_flags[i]);
2075 			if (IS_ERR(sfp->gpio[i]))
2076 				return PTR_ERR(sfp->gpio[i]);
2077 		}
2078 
2079 	sfp->get_state = sfp_gpio_get_state;
2080 	sfp->set_state = sfp_gpio_set_state;
2081 
2082 	/* Modules that have no detect signal are always present */
2083 	if (!(sfp->gpio[GPIO_MODDEF0]))
2084 		sfp->get_state = sff_gpio_get_state;
2085 
2086 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
2087 				 &sfp->max_power_mW);
2088 	if (!sfp->max_power_mW)
2089 		sfp->max_power_mW = 1000;
2090 
2091 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
2092 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
2093 
2094 	/* Get the initial state, and always signal TX disable,
2095 	 * since the network interface will not be up.
2096 	 */
2097 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
2098 
2099 	if (sfp->gpio[GPIO_RATE_SELECT] &&
2100 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RATE_SELECT]))
2101 		sfp->state |= SFP_F_RATE_SELECT;
2102 	sfp_set_state(sfp, sfp->state);
2103 	sfp_module_tx_disable(sfp);
2104 	if (sfp->state & SFP_F_PRESENT) {
2105 		rtnl_lock();
2106 		sfp_sm_event(sfp, SFP_E_INSERT);
2107 		rtnl_unlock();
2108 	}
2109 
2110 	for (i = 0; i < GPIO_MAX; i++) {
2111 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
2112 			continue;
2113 
2114 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
2115 		if (!sfp->gpio_irq[i]) {
2116 			poll = true;
2117 			continue;
2118 		}
2119 
2120 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
2121 						NULL, sfp_irq,
2122 						IRQF_ONESHOT |
2123 						IRQF_TRIGGER_RISING |
2124 						IRQF_TRIGGER_FALLING,
2125 						dev_name(sfp->dev), sfp);
2126 		if (err) {
2127 			sfp->gpio_irq[i] = 0;
2128 			poll = true;
2129 		}
2130 	}
2131 
2132 	if (poll)
2133 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2134 
2135 	/* We could have an issue in cases no Tx disable pin is available or
2136 	 * wired as modules using a laser as their light source will continue to
2137 	 * be active when the fiber is removed. This could be a safety issue and
2138 	 * we should at least warn the user about that.
2139 	 */
2140 	if (!sfp->gpio[GPIO_TX_DISABLE])
2141 		dev_warn(sfp->dev,
2142 			 "No tx_disable pin: SFP modules will always be emitting.\n");
2143 
2144 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
2145 	if (!sfp->sfp_bus)
2146 		return -ENOMEM;
2147 
2148 	return 0;
2149 }
2150 
2151 static int sfp_remove(struct platform_device *pdev)
2152 {
2153 	struct sfp *sfp = platform_get_drvdata(pdev);
2154 
2155 	sfp_unregister_socket(sfp->sfp_bus);
2156 
2157 	return 0;
2158 }
2159 
2160 static void sfp_shutdown(struct platform_device *pdev)
2161 {
2162 	struct sfp *sfp = platform_get_drvdata(pdev);
2163 	int i;
2164 
2165 	for (i = 0; i < GPIO_MAX; i++) {
2166 		if (!sfp->gpio_irq[i])
2167 			continue;
2168 
2169 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
2170 	}
2171 
2172 	cancel_delayed_work_sync(&sfp->poll);
2173 	cancel_delayed_work_sync(&sfp->timeout);
2174 }
2175 
2176 static struct platform_driver sfp_driver = {
2177 	.probe = sfp_probe,
2178 	.remove = sfp_remove,
2179 	.shutdown = sfp_shutdown,
2180 	.driver = {
2181 		.name = "sfp",
2182 		.of_match_table = sfp_of_match,
2183 	},
2184 };
2185 
2186 static int sfp_init(void)
2187 {
2188 	poll_jiffies = msecs_to_jiffies(100);
2189 
2190 	return platform_driver_register(&sfp_driver);
2191 }
2192 module_init(sfp_init);
2193 
2194 static void sfp_exit(void)
2195 {
2196 	platform_driver_unregister(&sfp_driver);
2197 }
2198 module_exit(sfp_exit);
2199 
2200 MODULE_ALIAS("platform:sfp");
2201 MODULE_AUTHOR("Russell King");
2202 MODULE_LICENSE("GPL v2");
2203