xref: /openbmc/linux/drivers/net/phy/sfp.c (revision 0c15d66d)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/debugfs.h>
3 #include <linux/delay.h>
4 #include <linux/gpio/consumer.h>
5 #include <linux/hwmon.h>
6 #include <linux/i2c.h>
7 #include <linux/interrupt.h>
8 #include <linux/jiffies.h>
9 #include <linux/mdio/mdio-i2c.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 "sfp.h"
20 #include "swphy.h"
21 
22 enum {
23 	GPIO_MODDEF0,
24 	GPIO_LOS,
25 	GPIO_TX_FAULT,
26 	GPIO_TX_DISABLE,
27 	GPIO_RATE_SELECT,
28 	GPIO_MAX,
29 
30 	SFP_F_PRESENT = BIT(GPIO_MODDEF0),
31 	SFP_F_LOS = BIT(GPIO_LOS),
32 	SFP_F_TX_FAULT = BIT(GPIO_TX_FAULT),
33 	SFP_F_TX_DISABLE = BIT(GPIO_TX_DISABLE),
34 	SFP_F_RATE_SELECT = BIT(GPIO_RATE_SELECT),
35 
36 	SFP_E_INSERT = 0,
37 	SFP_E_REMOVE,
38 	SFP_E_DEV_ATTACH,
39 	SFP_E_DEV_DETACH,
40 	SFP_E_DEV_DOWN,
41 	SFP_E_DEV_UP,
42 	SFP_E_TX_FAULT,
43 	SFP_E_TX_CLEAR,
44 	SFP_E_LOS_HIGH,
45 	SFP_E_LOS_LOW,
46 	SFP_E_TIMEOUT,
47 
48 	SFP_MOD_EMPTY = 0,
49 	SFP_MOD_ERROR,
50 	SFP_MOD_PROBE,
51 	SFP_MOD_WAITDEV,
52 	SFP_MOD_HPOWER,
53 	SFP_MOD_WAITPWR,
54 	SFP_MOD_PRESENT,
55 
56 	SFP_DEV_DETACHED = 0,
57 	SFP_DEV_DOWN,
58 	SFP_DEV_UP,
59 
60 	SFP_S_DOWN = 0,
61 	SFP_S_FAIL,
62 	SFP_S_WAIT,
63 	SFP_S_INIT,
64 	SFP_S_INIT_PHY,
65 	SFP_S_INIT_TX_FAULT,
66 	SFP_S_WAIT_LOS,
67 	SFP_S_LINK_UP,
68 	SFP_S_TX_FAULT,
69 	SFP_S_REINIT,
70 	SFP_S_TX_DISABLE,
71 };
72 
73 static const char  * const mod_state_strings[] = {
74 	[SFP_MOD_EMPTY] = "empty",
75 	[SFP_MOD_ERROR] = "error",
76 	[SFP_MOD_PROBE] = "probe",
77 	[SFP_MOD_WAITDEV] = "waitdev",
78 	[SFP_MOD_HPOWER] = "hpower",
79 	[SFP_MOD_WAITPWR] = "waitpwr",
80 	[SFP_MOD_PRESENT] = "present",
81 };
82 
83 static const char *mod_state_to_str(unsigned short mod_state)
84 {
85 	if (mod_state >= ARRAY_SIZE(mod_state_strings))
86 		return "Unknown module state";
87 	return mod_state_strings[mod_state];
88 }
89 
90 static const char * const dev_state_strings[] = {
91 	[SFP_DEV_DETACHED] = "detached",
92 	[SFP_DEV_DOWN] = "down",
93 	[SFP_DEV_UP] = "up",
94 };
95 
96 static const char *dev_state_to_str(unsigned short dev_state)
97 {
98 	if (dev_state >= ARRAY_SIZE(dev_state_strings))
99 		return "Unknown device state";
100 	return dev_state_strings[dev_state];
101 }
102 
103 static const char * const event_strings[] = {
104 	[SFP_E_INSERT] = "insert",
105 	[SFP_E_REMOVE] = "remove",
106 	[SFP_E_DEV_ATTACH] = "dev_attach",
107 	[SFP_E_DEV_DETACH] = "dev_detach",
108 	[SFP_E_DEV_DOWN] = "dev_down",
109 	[SFP_E_DEV_UP] = "dev_up",
110 	[SFP_E_TX_FAULT] = "tx_fault",
111 	[SFP_E_TX_CLEAR] = "tx_clear",
112 	[SFP_E_LOS_HIGH] = "los_high",
113 	[SFP_E_LOS_LOW] = "los_low",
114 	[SFP_E_TIMEOUT] = "timeout",
115 };
116 
117 static const char *event_to_str(unsigned short event)
118 {
119 	if (event >= ARRAY_SIZE(event_strings))
120 		return "Unknown event";
121 	return event_strings[event];
122 }
123 
124 static const char * const sm_state_strings[] = {
125 	[SFP_S_DOWN] = "down",
126 	[SFP_S_FAIL] = "fail",
127 	[SFP_S_WAIT] = "wait",
128 	[SFP_S_INIT] = "init",
129 	[SFP_S_INIT_PHY] = "init_phy",
130 	[SFP_S_INIT_TX_FAULT] = "init_tx_fault",
131 	[SFP_S_WAIT_LOS] = "wait_los",
132 	[SFP_S_LINK_UP] = "link_up",
133 	[SFP_S_TX_FAULT] = "tx_fault",
134 	[SFP_S_REINIT] = "reinit",
135 	[SFP_S_TX_DISABLE] = "tx_disable",
136 };
137 
138 static const char *sm_state_to_str(unsigned short sm_state)
139 {
140 	if (sm_state >= ARRAY_SIZE(sm_state_strings))
141 		return "Unknown state";
142 	return sm_state_strings[sm_state];
143 }
144 
145 static const char *gpio_names[] = {
146 	"mod-def0",
147 	"los",
148 	"tx-fault",
149 	"tx-disable",
150 	"rate-select0",
151 };
152 
153 static const enum gpiod_flags gpio_flags[] = {
154 	GPIOD_IN,
155 	GPIOD_IN,
156 	GPIOD_IN,
157 	GPIOD_ASIS,
158 	GPIOD_ASIS,
159 };
160 
161 /* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
162  * non-cooled module to initialise its laser safety circuitry. We wait
163  * an initial T_WAIT period before we check the tx fault to give any PHY
164  * on board (for a copper SFP) time to initialise.
165  */
166 #define T_WAIT			msecs_to_jiffies(50)
167 #define T_WAIT_ROLLBALL		msecs_to_jiffies(25000)
168 #define T_START_UP		msecs_to_jiffies(300)
169 #define T_START_UP_BAD_GPON	msecs_to_jiffies(60000)
170 
171 /* t_reset is the time required to assert the TX_DISABLE signal to reset
172  * an indicated TX_FAULT.
173  */
174 #define T_RESET_US		10
175 #define T_FAULT_RECOVER		msecs_to_jiffies(1000)
176 
177 /* N_FAULT_INIT is the number of recovery attempts at module initialisation
178  * time. If the TX_FAULT signal is not deasserted after this number of
179  * attempts at clearing it, we decide that the module is faulty.
180  * N_FAULT is the same but after the module has initialised.
181  */
182 #define N_FAULT_INIT		5
183 #define N_FAULT			5
184 
185 /* T_PHY_RETRY is the time interval between attempts to probe the PHY.
186  * R_PHY_RETRY is the number of attempts.
187  */
188 #define T_PHY_RETRY		msecs_to_jiffies(50)
189 #define R_PHY_RETRY		12
190 
191 /* SFP module presence detection is poor: the three MOD DEF signals are
192  * the same length on the PCB, which means it's possible for MOD DEF 0 to
193  * connect before the I2C bus on MOD DEF 1/2.
194  *
195  * The SFF-8472 specifies t_serial ("Time from power on until module is
196  * ready for data transmission over the two wire serial bus.") as 300ms.
197  */
198 #define T_SERIAL		msecs_to_jiffies(300)
199 #define T_HPOWER_LEVEL		msecs_to_jiffies(300)
200 #define T_PROBE_RETRY_INIT	msecs_to_jiffies(100)
201 #define R_PROBE_RETRY_INIT	10
202 #define T_PROBE_RETRY_SLOW	msecs_to_jiffies(5000)
203 #define R_PROBE_RETRY_SLOW	12
204 
205 /* SFP modules appear to always have their PHY configured for bus address
206  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
207  * RollBall SFPs access phy via SFP Enhanced Digital Diagnostic Interface
208  * via address 0x51 (mdio-i2c will use RollBall protocol on this address).
209  */
210 #define SFP_PHY_ADDR		22
211 #define SFP_PHY_ADDR_ROLLBALL	17
212 
213 struct sff_data {
214 	unsigned int gpios;
215 	bool (*module_supported)(const struct sfp_eeprom_id *id);
216 };
217 
218 struct sfp {
219 	struct device *dev;
220 	struct i2c_adapter *i2c;
221 	struct mii_bus *i2c_mii;
222 	struct sfp_bus *sfp_bus;
223 	enum mdio_i2c_proto mdio_protocol;
224 	struct phy_device *mod_phy;
225 	const struct sff_data *type;
226 	size_t i2c_block_size;
227 	u32 max_power_mW;
228 
229 	unsigned int (*get_state)(struct sfp *);
230 	void (*set_state)(struct sfp *, unsigned int);
231 	int (*read)(struct sfp *, bool, u8, void *, size_t);
232 	int (*write)(struct sfp *, bool, u8, void *, size_t);
233 
234 	struct gpio_desc *gpio[GPIO_MAX];
235 	int gpio_irq[GPIO_MAX];
236 
237 	bool need_poll;
238 
239 	struct mutex st_mutex;			/* Protects state */
240 	unsigned int state_hw_mask;
241 	unsigned int state_soft_mask;
242 	unsigned int state;
243 	struct delayed_work poll;
244 	struct delayed_work timeout;
245 	struct mutex sm_mutex;			/* Protects state machine */
246 	unsigned char sm_mod_state;
247 	unsigned char sm_mod_tries_init;
248 	unsigned char sm_mod_tries;
249 	unsigned char sm_dev_state;
250 	unsigned short sm_state;
251 	unsigned char sm_fault_retries;
252 	unsigned char sm_phy_retries;
253 
254 	struct sfp_eeprom_id id;
255 	unsigned int module_power_mW;
256 	unsigned int module_t_start_up;
257 	unsigned int module_t_wait;
258 	bool tx_fault_ignore;
259 
260 	const struct sfp_quirk *quirk;
261 
262 #if IS_ENABLED(CONFIG_HWMON)
263 	struct sfp_diag diag;
264 	struct delayed_work hwmon_probe;
265 	unsigned int hwmon_tries;
266 	struct device *hwmon_dev;
267 	char *hwmon_name;
268 #endif
269 
270 #if IS_ENABLED(CONFIG_DEBUG_FS)
271 	struct dentry *debugfs_dir;
272 #endif
273 };
274 
275 static bool sff_module_supported(const struct sfp_eeprom_id *id)
276 {
277 	return id->base.phys_id == SFF8024_ID_SFF_8472 &&
278 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
279 }
280 
281 static const struct sff_data sff_data = {
282 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
283 	.module_supported = sff_module_supported,
284 };
285 
286 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
287 {
288 	if (id->base.phys_id == SFF8024_ID_SFP &&
289 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP)
290 		return true;
291 
292 	/* SFP GPON module Ubiquiti U-Fiber Instant has in its EEPROM stored
293 	 * phys id SFF instead of SFP. Therefore mark this module explicitly
294 	 * as supported based on vendor name and pn match.
295 	 */
296 	if (id->base.phys_id == SFF8024_ID_SFF_8472 &&
297 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP &&
298 	    !memcmp(id->base.vendor_name, "UBNT            ", 16) &&
299 	    !memcmp(id->base.vendor_pn, "UF-INSTANT      ", 16))
300 		return true;
301 
302 	return false;
303 }
304 
305 static const struct sff_data sfp_data = {
306 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
307 		 SFP_F_TX_DISABLE | SFP_F_RATE_SELECT,
308 	.module_supported = sfp_module_supported,
309 };
310 
311 static const struct of_device_id sfp_of_match[] = {
312 	{ .compatible = "sff,sff", .data = &sff_data, },
313 	{ .compatible = "sff,sfp", .data = &sfp_data, },
314 	{ },
315 };
316 MODULE_DEVICE_TABLE(of, sfp_of_match);
317 
318 static void sfp_fixup_long_startup(struct sfp *sfp)
319 {
320 	sfp->module_t_start_up = T_START_UP_BAD_GPON;
321 }
322 
323 static void sfp_fixup_ignore_tx_fault(struct sfp *sfp)
324 {
325 	sfp->tx_fault_ignore = true;
326 }
327 
328 static void sfp_fixup_halny_gsfp(struct sfp *sfp)
329 {
330 	/* Ignore the TX_FAULT and LOS signals on this module.
331 	 * these are possibly used for other purposes on this
332 	 * module, e.g. a serial port.
333 	 */
334 	sfp->state_hw_mask &= ~(SFP_F_TX_FAULT | SFP_F_LOS);
335 }
336 
337 static void sfp_fixup_rollball(struct sfp *sfp)
338 {
339 	sfp->mdio_protocol = MDIO_I2C_ROLLBALL;
340 	sfp->module_t_wait = T_WAIT_ROLLBALL;
341 }
342 
343 static void sfp_fixup_rollball_cc(struct sfp *sfp)
344 {
345 	sfp_fixup_rollball(sfp);
346 
347 	/* Some RollBall SFPs may have wrong (zero) extended compliance code
348 	 * burned in EEPROM. For PHY probing we need the correct one.
349 	 */
350 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SFI;
351 }
352 
353 static void sfp_quirk_2500basex(const struct sfp_eeprom_id *id,
354 				unsigned long *modes,
355 				unsigned long *interfaces)
356 {
357 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseX_Full_BIT, modes);
358 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
359 }
360 
361 static void sfp_quirk_ubnt_uf_instant(const struct sfp_eeprom_id *id,
362 				      unsigned long *modes,
363 				      unsigned long *interfaces)
364 {
365 	/* Ubiquiti U-Fiber Instant module claims that support all transceiver
366 	 * types including 10G Ethernet which is not truth. So clear all claimed
367 	 * modes and set only one mode which module supports: 1000baseX_Full.
368 	 */
369 	linkmode_zero(modes);
370 	linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT, modes);
371 }
372 
373 #define SFP_QUIRK(_v, _p, _m, _f) \
374 	{ .vendor = _v, .part = _p, .modes = _m, .fixup = _f, }
375 #define SFP_QUIRK_M(_v, _p, _m) SFP_QUIRK(_v, _p, _m, NULL)
376 #define SFP_QUIRK_F(_v, _p, _f) SFP_QUIRK(_v, _p, NULL, _f)
377 
378 static const struct sfp_quirk sfp_quirks[] = {
379 	// Alcatel Lucent G-010S-P can operate at 2500base-X, but incorrectly
380 	// report 2500MBd NRZ in their EEPROM
381 	SFP_QUIRK_M("ALCATELLUCENT", "G010SP", sfp_quirk_2500basex),
382 
383 	// Alcatel Lucent G-010S-A can operate at 2500base-X, but report 3.2GBd
384 	// NRZ in their EEPROM
385 	SFP_QUIRK("ALCATELLUCENT", "3FE46541AA", sfp_quirk_2500basex,
386 		  sfp_fixup_long_startup),
387 
388 	SFP_QUIRK_F("HALNy", "HL-GSFP", sfp_fixup_halny_gsfp),
389 
390 	// Huawei MA5671A can operate at 2500base-X, but report 1.2GBd NRZ in
391 	// their EEPROM
392 	SFP_QUIRK("HUAWEI", "MA5671A", sfp_quirk_2500basex,
393 		  sfp_fixup_ignore_tx_fault),
394 
395 	// Lantech 8330-262D-E can operate at 2500base-X, but incorrectly report
396 	// 2500MBd NRZ in their EEPROM
397 	SFP_QUIRK_M("Lantech", "8330-262D-E", sfp_quirk_2500basex),
398 
399 	SFP_QUIRK_M("UBNT", "UF-INSTANT", sfp_quirk_ubnt_uf_instant),
400 
401 	SFP_QUIRK_F("OEM", "SFP-10G-T", sfp_fixup_rollball_cc),
402 	SFP_QUIRK_F("OEM", "RTSFP-10", sfp_fixup_rollball_cc),
403 	SFP_QUIRK_F("OEM", "RTSFP-10G", sfp_fixup_rollball_cc),
404 	SFP_QUIRK_F("Turris", "RTSFP-10", sfp_fixup_rollball),
405 	SFP_QUIRK_F("Turris", "RTSFP-10G", sfp_fixup_rollball),
406 };
407 
408 static size_t sfp_strlen(const char *str, size_t maxlen)
409 {
410 	size_t size, i;
411 
412 	/* Trailing characters should be filled with space chars, but
413 	 * some manufacturers can't read SFF-8472 and use NUL.
414 	 */
415 	for (i = 0, size = 0; i < maxlen; i++)
416 		if (str[i] != ' ' && str[i] != '\0')
417 			size = i + 1;
418 
419 	return size;
420 }
421 
422 static bool sfp_match(const char *qs, const char *str, size_t len)
423 {
424 	if (!qs)
425 		return true;
426 	if (strlen(qs) != len)
427 		return false;
428 	return !strncmp(qs, str, len);
429 }
430 
431 static const struct sfp_quirk *sfp_lookup_quirk(const struct sfp_eeprom_id *id)
432 {
433 	const struct sfp_quirk *q;
434 	unsigned int i;
435 	size_t vs, ps;
436 
437 	vs = sfp_strlen(id->base.vendor_name, ARRAY_SIZE(id->base.vendor_name));
438 	ps = sfp_strlen(id->base.vendor_pn, ARRAY_SIZE(id->base.vendor_pn));
439 
440 	for (i = 0, q = sfp_quirks; i < ARRAY_SIZE(sfp_quirks); i++, q++)
441 		if (sfp_match(q->vendor, id->base.vendor_name, vs) &&
442 		    sfp_match(q->part, id->base.vendor_pn, ps))
443 			return q;
444 
445 	return NULL;
446 }
447 
448 static unsigned long poll_jiffies;
449 
450 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
451 {
452 	unsigned int i, state, v;
453 
454 	for (i = state = 0; i < GPIO_MAX; i++) {
455 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
456 			continue;
457 
458 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
459 		if (v)
460 			state |= BIT(i);
461 	}
462 
463 	return state;
464 }
465 
466 static unsigned int sff_gpio_get_state(struct sfp *sfp)
467 {
468 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
469 }
470 
471 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
472 {
473 	if (state & SFP_F_PRESENT) {
474 		/* If the module is present, drive the signals */
475 		if (sfp->gpio[GPIO_TX_DISABLE])
476 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
477 					       state & SFP_F_TX_DISABLE);
478 		if (state & SFP_F_RATE_SELECT)
479 			gpiod_direction_output(sfp->gpio[GPIO_RATE_SELECT],
480 					       state & SFP_F_RATE_SELECT);
481 	} else {
482 		/* Otherwise, let them float to the pull-ups */
483 		if (sfp->gpio[GPIO_TX_DISABLE])
484 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
485 		if (state & SFP_F_RATE_SELECT)
486 			gpiod_direction_input(sfp->gpio[GPIO_RATE_SELECT]);
487 	}
488 }
489 
490 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
491 			size_t len)
492 {
493 	struct i2c_msg msgs[2];
494 	u8 bus_addr = a2 ? 0x51 : 0x50;
495 	size_t block_size = sfp->i2c_block_size;
496 	size_t this_len;
497 	int ret;
498 
499 	msgs[0].addr = bus_addr;
500 	msgs[0].flags = 0;
501 	msgs[0].len = 1;
502 	msgs[0].buf = &dev_addr;
503 	msgs[1].addr = bus_addr;
504 	msgs[1].flags = I2C_M_RD;
505 	msgs[1].len = len;
506 	msgs[1].buf = buf;
507 
508 	while (len) {
509 		this_len = len;
510 		if (this_len > block_size)
511 			this_len = block_size;
512 
513 		msgs[1].len = this_len;
514 
515 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
516 		if (ret < 0)
517 			return ret;
518 
519 		if (ret != ARRAY_SIZE(msgs))
520 			break;
521 
522 		msgs[1].buf += this_len;
523 		dev_addr += this_len;
524 		len -= this_len;
525 	}
526 
527 	return msgs[1].buf - (u8 *)buf;
528 }
529 
530 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
531 	size_t len)
532 {
533 	struct i2c_msg msgs[1];
534 	u8 bus_addr = a2 ? 0x51 : 0x50;
535 	int ret;
536 
537 	msgs[0].addr = bus_addr;
538 	msgs[0].flags = 0;
539 	msgs[0].len = 1 + len;
540 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
541 	if (!msgs[0].buf)
542 		return -ENOMEM;
543 
544 	msgs[0].buf[0] = dev_addr;
545 	memcpy(&msgs[0].buf[1], buf, len);
546 
547 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
548 
549 	kfree(msgs[0].buf);
550 
551 	if (ret < 0)
552 		return ret;
553 
554 	return ret == ARRAY_SIZE(msgs) ? len : 0;
555 }
556 
557 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
558 {
559 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
560 		return -EINVAL;
561 
562 	sfp->i2c = i2c;
563 	sfp->read = sfp_i2c_read;
564 	sfp->write = sfp_i2c_write;
565 
566 	return 0;
567 }
568 
569 static int sfp_i2c_mdiobus_create(struct sfp *sfp)
570 {
571 	struct mii_bus *i2c_mii;
572 	int ret;
573 
574 	i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, sfp->mdio_protocol);
575 	if (IS_ERR(i2c_mii))
576 		return PTR_ERR(i2c_mii);
577 
578 	i2c_mii->name = "SFP I2C Bus";
579 	i2c_mii->phy_mask = ~0;
580 
581 	ret = mdiobus_register(i2c_mii);
582 	if (ret < 0) {
583 		mdiobus_free(i2c_mii);
584 		return ret;
585 	}
586 
587 	sfp->i2c_mii = i2c_mii;
588 
589 	return 0;
590 }
591 
592 static void sfp_i2c_mdiobus_destroy(struct sfp *sfp)
593 {
594 	mdiobus_unregister(sfp->i2c_mii);
595 	sfp->i2c_mii = NULL;
596 }
597 
598 /* Interface */
599 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
600 {
601 	return sfp->read(sfp, a2, addr, buf, len);
602 }
603 
604 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
605 {
606 	return sfp->write(sfp, a2, addr, buf, len);
607 }
608 
609 static int sfp_modify_u8(struct sfp *sfp, bool a2, u8 addr, u8 mask, u8 val)
610 {
611 	int ret;
612 	u8 old, v;
613 
614 	ret = sfp_read(sfp, a2, addr, &old, sizeof(old));
615 	if (ret != sizeof(old))
616 		return ret;
617 
618 	v = (old & ~mask) | (val & mask);
619 	if (v == old)
620 		return sizeof(v);
621 
622 	return sfp_write(sfp, a2, addr, &v, sizeof(v));
623 }
624 
625 static unsigned int sfp_soft_get_state(struct sfp *sfp)
626 {
627 	unsigned int state = 0;
628 	u8 status;
629 	int ret;
630 
631 	ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
632 	if (ret == sizeof(status)) {
633 		if (status & SFP_STATUS_RX_LOS)
634 			state |= SFP_F_LOS;
635 		if (status & SFP_STATUS_TX_FAULT)
636 			state |= SFP_F_TX_FAULT;
637 	} else {
638 		dev_err_ratelimited(sfp->dev,
639 				    "failed to read SFP soft status: %pe\n",
640 				    ERR_PTR(ret));
641 		/* Preserve the current state */
642 		state = sfp->state;
643 	}
644 
645 	return state & sfp->state_soft_mask;
646 }
647 
648 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state)
649 {
650 	u8 mask = SFP_STATUS_TX_DISABLE_FORCE;
651 	u8 val = 0;
652 
653 	if (state & SFP_F_TX_DISABLE)
654 		val |= SFP_STATUS_TX_DISABLE_FORCE;
655 
656 
657 	sfp_modify_u8(sfp, true, SFP_STATUS, mask, val);
658 }
659 
660 static void sfp_soft_start_poll(struct sfp *sfp)
661 {
662 	const struct sfp_eeprom_id *id = &sfp->id;
663 	unsigned int mask = 0;
664 
665 	sfp->state_soft_mask = 0;
666 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE)
667 		mask |= SFP_F_TX_DISABLE;
668 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT)
669 		mask |= SFP_F_TX_FAULT;
670 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS)
671 		mask |= SFP_F_LOS;
672 
673 	// Poll the soft state for hardware pins we want to ignore
674 	sfp->state_soft_mask = ~sfp->state_hw_mask & mask;
675 
676 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
677 	    !sfp->need_poll)
678 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
679 }
680 
681 static void sfp_soft_stop_poll(struct sfp *sfp)
682 {
683 	sfp->state_soft_mask = 0;
684 }
685 
686 static unsigned int sfp_get_state(struct sfp *sfp)
687 {
688 	unsigned int soft = sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT);
689 	unsigned int state;
690 
691 	state = sfp->get_state(sfp) & sfp->state_hw_mask;
692 	if (state & SFP_F_PRESENT && soft)
693 		state |= sfp_soft_get_state(sfp);
694 
695 	return state;
696 }
697 
698 static void sfp_set_state(struct sfp *sfp, unsigned int state)
699 {
700 	sfp->set_state(sfp, state);
701 
702 	if (state & SFP_F_PRESENT &&
703 	    sfp->state_soft_mask & SFP_F_TX_DISABLE)
704 		sfp_soft_set_state(sfp, state);
705 }
706 
707 static unsigned int sfp_check(void *buf, size_t len)
708 {
709 	u8 *p, check;
710 
711 	for (p = buf, check = 0; len; p++, len--)
712 		check += *p;
713 
714 	return check;
715 }
716 
717 /* hwmon */
718 #if IS_ENABLED(CONFIG_HWMON)
719 static umode_t sfp_hwmon_is_visible(const void *data,
720 				    enum hwmon_sensor_types type,
721 				    u32 attr, int channel)
722 {
723 	const struct sfp *sfp = data;
724 
725 	switch (type) {
726 	case hwmon_temp:
727 		switch (attr) {
728 		case hwmon_temp_min_alarm:
729 		case hwmon_temp_max_alarm:
730 		case hwmon_temp_lcrit_alarm:
731 		case hwmon_temp_crit_alarm:
732 		case hwmon_temp_min:
733 		case hwmon_temp_max:
734 		case hwmon_temp_lcrit:
735 		case hwmon_temp_crit:
736 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
737 				return 0;
738 			fallthrough;
739 		case hwmon_temp_input:
740 		case hwmon_temp_label:
741 			return 0444;
742 		default:
743 			return 0;
744 		}
745 	case hwmon_in:
746 		switch (attr) {
747 		case hwmon_in_min_alarm:
748 		case hwmon_in_max_alarm:
749 		case hwmon_in_lcrit_alarm:
750 		case hwmon_in_crit_alarm:
751 		case hwmon_in_min:
752 		case hwmon_in_max:
753 		case hwmon_in_lcrit:
754 		case hwmon_in_crit:
755 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
756 				return 0;
757 			fallthrough;
758 		case hwmon_in_input:
759 		case hwmon_in_label:
760 			return 0444;
761 		default:
762 			return 0;
763 		}
764 	case hwmon_curr:
765 		switch (attr) {
766 		case hwmon_curr_min_alarm:
767 		case hwmon_curr_max_alarm:
768 		case hwmon_curr_lcrit_alarm:
769 		case hwmon_curr_crit_alarm:
770 		case hwmon_curr_min:
771 		case hwmon_curr_max:
772 		case hwmon_curr_lcrit:
773 		case hwmon_curr_crit:
774 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
775 				return 0;
776 			fallthrough;
777 		case hwmon_curr_input:
778 		case hwmon_curr_label:
779 			return 0444;
780 		default:
781 			return 0;
782 		}
783 	case hwmon_power:
784 		/* External calibration of receive power requires
785 		 * floating point arithmetic. Doing that in the kernel
786 		 * is not easy, so just skip it. If the module does
787 		 * not require external calibration, we can however
788 		 * show receiver power, since FP is then not needed.
789 		 */
790 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
791 		    channel == 1)
792 			return 0;
793 		switch (attr) {
794 		case hwmon_power_min_alarm:
795 		case hwmon_power_max_alarm:
796 		case hwmon_power_lcrit_alarm:
797 		case hwmon_power_crit_alarm:
798 		case hwmon_power_min:
799 		case hwmon_power_max:
800 		case hwmon_power_lcrit:
801 		case hwmon_power_crit:
802 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
803 				return 0;
804 			fallthrough;
805 		case hwmon_power_input:
806 		case hwmon_power_label:
807 			return 0444;
808 		default:
809 			return 0;
810 		}
811 	default:
812 		return 0;
813 	}
814 }
815 
816 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
817 {
818 	__be16 val;
819 	int err;
820 
821 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
822 	if (err < 0)
823 		return err;
824 
825 	*value = be16_to_cpu(val);
826 
827 	return 0;
828 }
829 
830 static void sfp_hwmon_to_rx_power(long *value)
831 {
832 	*value = DIV_ROUND_CLOSEST(*value, 10);
833 }
834 
835 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
836 				long *value)
837 {
838 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
839 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
840 }
841 
842 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
843 {
844 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
845 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
846 
847 	if (*value >= 0x8000)
848 		*value -= 0x10000;
849 
850 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
851 }
852 
853 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
854 {
855 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
856 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
857 
858 	*value = DIV_ROUND_CLOSEST(*value, 10);
859 }
860 
861 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
862 {
863 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
864 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
865 
866 	*value = DIV_ROUND_CLOSEST(*value, 500);
867 }
868 
869 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
870 {
871 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
872 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
873 
874 	*value = DIV_ROUND_CLOSEST(*value, 10);
875 }
876 
877 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
878 {
879 	int err;
880 
881 	err = sfp_hwmon_read_sensor(sfp, reg, value);
882 	if (err < 0)
883 		return err;
884 
885 	sfp_hwmon_calibrate_temp(sfp, value);
886 
887 	return 0;
888 }
889 
890 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
891 {
892 	int err;
893 
894 	err = sfp_hwmon_read_sensor(sfp, reg, value);
895 	if (err < 0)
896 		return err;
897 
898 	sfp_hwmon_calibrate_vcc(sfp, value);
899 
900 	return 0;
901 }
902 
903 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
904 {
905 	int err;
906 
907 	err = sfp_hwmon_read_sensor(sfp, reg, value);
908 	if (err < 0)
909 		return err;
910 
911 	sfp_hwmon_calibrate_bias(sfp, value);
912 
913 	return 0;
914 }
915 
916 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
917 {
918 	int err;
919 
920 	err = sfp_hwmon_read_sensor(sfp, reg, value);
921 	if (err < 0)
922 		return err;
923 
924 	sfp_hwmon_calibrate_tx_power(sfp, value);
925 
926 	return 0;
927 }
928 
929 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
930 {
931 	int err;
932 
933 	err = sfp_hwmon_read_sensor(sfp, reg, value);
934 	if (err < 0)
935 		return err;
936 
937 	sfp_hwmon_to_rx_power(value);
938 
939 	return 0;
940 }
941 
942 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
943 {
944 	u8 status;
945 	int err;
946 
947 	switch (attr) {
948 	case hwmon_temp_input:
949 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
950 
951 	case hwmon_temp_lcrit:
952 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
953 		sfp_hwmon_calibrate_temp(sfp, value);
954 		return 0;
955 
956 	case hwmon_temp_min:
957 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
958 		sfp_hwmon_calibrate_temp(sfp, value);
959 		return 0;
960 	case hwmon_temp_max:
961 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
962 		sfp_hwmon_calibrate_temp(sfp, value);
963 		return 0;
964 
965 	case hwmon_temp_crit:
966 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
967 		sfp_hwmon_calibrate_temp(sfp, value);
968 		return 0;
969 
970 	case hwmon_temp_lcrit_alarm:
971 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
972 		if (err < 0)
973 			return err;
974 
975 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
976 		return 0;
977 
978 	case hwmon_temp_min_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_TEMP_LOW);
984 		return 0;
985 
986 	case hwmon_temp_max_alarm:
987 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
988 		if (err < 0)
989 			return err;
990 
991 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
992 		return 0;
993 
994 	case hwmon_temp_crit_alarm:
995 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
996 		if (err < 0)
997 			return err;
998 
999 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
1000 		return 0;
1001 	default:
1002 		return -EOPNOTSUPP;
1003 	}
1004 
1005 	return -EOPNOTSUPP;
1006 }
1007 
1008 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
1009 {
1010 	u8 status;
1011 	int err;
1012 
1013 	switch (attr) {
1014 	case hwmon_in_input:
1015 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
1016 
1017 	case hwmon_in_lcrit:
1018 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
1019 		sfp_hwmon_calibrate_vcc(sfp, value);
1020 		return 0;
1021 
1022 	case hwmon_in_min:
1023 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
1024 		sfp_hwmon_calibrate_vcc(sfp, value);
1025 		return 0;
1026 
1027 	case hwmon_in_max:
1028 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
1029 		sfp_hwmon_calibrate_vcc(sfp, value);
1030 		return 0;
1031 
1032 	case hwmon_in_crit:
1033 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
1034 		sfp_hwmon_calibrate_vcc(sfp, value);
1035 		return 0;
1036 
1037 	case hwmon_in_lcrit_alarm:
1038 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1039 		if (err < 0)
1040 			return err;
1041 
1042 		*value = !!(status & SFP_ALARM0_VCC_LOW);
1043 		return 0;
1044 
1045 	case hwmon_in_min_alarm:
1046 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1047 		if (err < 0)
1048 			return err;
1049 
1050 		*value = !!(status & SFP_WARN0_VCC_LOW);
1051 		return 0;
1052 
1053 	case hwmon_in_max_alarm:
1054 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1055 		if (err < 0)
1056 			return err;
1057 
1058 		*value = !!(status & SFP_WARN0_VCC_HIGH);
1059 		return 0;
1060 
1061 	case hwmon_in_crit_alarm:
1062 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1063 		if (err < 0)
1064 			return err;
1065 
1066 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
1067 		return 0;
1068 	default:
1069 		return -EOPNOTSUPP;
1070 	}
1071 
1072 	return -EOPNOTSUPP;
1073 }
1074 
1075 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
1076 {
1077 	u8 status;
1078 	int err;
1079 
1080 	switch (attr) {
1081 	case hwmon_curr_input:
1082 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
1083 
1084 	case hwmon_curr_lcrit:
1085 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
1086 		sfp_hwmon_calibrate_bias(sfp, value);
1087 		return 0;
1088 
1089 	case hwmon_curr_min:
1090 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
1091 		sfp_hwmon_calibrate_bias(sfp, value);
1092 		return 0;
1093 
1094 	case hwmon_curr_max:
1095 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
1096 		sfp_hwmon_calibrate_bias(sfp, value);
1097 		return 0;
1098 
1099 	case hwmon_curr_crit:
1100 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
1101 		sfp_hwmon_calibrate_bias(sfp, value);
1102 		return 0;
1103 
1104 	case hwmon_curr_lcrit_alarm:
1105 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1106 		if (err < 0)
1107 			return err;
1108 
1109 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
1110 		return 0;
1111 
1112 	case hwmon_curr_min_alarm:
1113 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1114 		if (err < 0)
1115 			return err;
1116 
1117 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
1118 		return 0;
1119 
1120 	case hwmon_curr_max_alarm:
1121 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1122 		if (err < 0)
1123 			return err;
1124 
1125 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
1126 		return 0;
1127 
1128 	case hwmon_curr_crit_alarm:
1129 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1130 		if (err < 0)
1131 			return err;
1132 
1133 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
1134 		return 0;
1135 	default:
1136 		return -EOPNOTSUPP;
1137 	}
1138 
1139 	return -EOPNOTSUPP;
1140 }
1141 
1142 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
1143 {
1144 	u8 status;
1145 	int err;
1146 
1147 	switch (attr) {
1148 	case hwmon_power_input:
1149 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
1150 
1151 	case hwmon_power_lcrit:
1152 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
1153 		sfp_hwmon_calibrate_tx_power(sfp, value);
1154 		return 0;
1155 
1156 	case hwmon_power_min:
1157 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
1158 		sfp_hwmon_calibrate_tx_power(sfp, value);
1159 		return 0;
1160 
1161 	case hwmon_power_max:
1162 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
1163 		sfp_hwmon_calibrate_tx_power(sfp, value);
1164 		return 0;
1165 
1166 	case hwmon_power_crit:
1167 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
1168 		sfp_hwmon_calibrate_tx_power(sfp, value);
1169 		return 0;
1170 
1171 	case hwmon_power_lcrit_alarm:
1172 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1173 		if (err < 0)
1174 			return err;
1175 
1176 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
1177 		return 0;
1178 
1179 	case hwmon_power_min_alarm:
1180 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1181 		if (err < 0)
1182 			return err;
1183 
1184 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
1185 		return 0;
1186 
1187 	case hwmon_power_max_alarm:
1188 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1189 		if (err < 0)
1190 			return err;
1191 
1192 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1193 		return 0;
1194 
1195 	case hwmon_power_crit_alarm:
1196 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1197 		if (err < 0)
1198 			return err;
1199 
1200 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1201 		return 0;
1202 	default:
1203 		return -EOPNOTSUPP;
1204 	}
1205 
1206 	return -EOPNOTSUPP;
1207 }
1208 
1209 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1210 {
1211 	u8 status;
1212 	int err;
1213 
1214 	switch (attr) {
1215 	case hwmon_power_input:
1216 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1217 
1218 	case hwmon_power_lcrit:
1219 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1220 		sfp_hwmon_to_rx_power(value);
1221 		return 0;
1222 
1223 	case hwmon_power_min:
1224 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1225 		sfp_hwmon_to_rx_power(value);
1226 		return 0;
1227 
1228 	case hwmon_power_max:
1229 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1230 		sfp_hwmon_to_rx_power(value);
1231 		return 0;
1232 
1233 	case hwmon_power_crit:
1234 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1235 		sfp_hwmon_to_rx_power(value);
1236 		return 0;
1237 
1238 	case hwmon_power_lcrit_alarm:
1239 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1240 		if (err < 0)
1241 			return err;
1242 
1243 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1244 		return 0;
1245 
1246 	case hwmon_power_min_alarm:
1247 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1248 		if (err < 0)
1249 			return err;
1250 
1251 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1252 		return 0;
1253 
1254 	case hwmon_power_max_alarm:
1255 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1256 		if (err < 0)
1257 			return err;
1258 
1259 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1260 		return 0;
1261 
1262 	case hwmon_power_crit_alarm:
1263 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1264 		if (err < 0)
1265 			return err;
1266 
1267 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1268 		return 0;
1269 	default:
1270 		return -EOPNOTSUPP;
1271 	}
1272 
1273 	return -EOPNOTSUPP;
1274 }
1275 
1276 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1277 			  u32 attr, int channel, long *value)
1278 {
1279 	struct sfp *sfp = dev_get_drvdata(dev);
1280 
1281 	switch (type) {
1282 	case hwmon_temp:
1283 		return sfp_hwmon_temp(sfp, attr, value);
1284 	case hwmon_in:
1285 		return sfp_hwmon_vcc(sfp, attr, value);
1286 	case hwmon_curr:
1287 		return sfp_hwmon_bias(sfp, attr, value);
1288 	case hwmon_power:
1289 		switch (channel) {
1290 		case 0:
1291 			return sfp_hwmon_tx_power(sfp, attr, value);
1292 		case 1:
1293 			return sfp_hwmon_rx_power(sfp, attr, value);
1294 		default:
1295 			return -EOPNOTSUPP;
1296 		}
1297 	default:
1298 		return -EOPNOTSUPP;
1299 	}
1300 }
1301 
1302 static const char *const sfp_hwmon_power_labels[] = {
1303 	"TX_power",
1304 	"RX_power",
1305 };
1306 
1307 static int sfp_hwmon_read_string(struct device *dev,
1308 				 enum hwmon_sensor_types type,
1309 				 u32 attr, int channel, const char **str)
1310 {
1311 	switch (type) {
1312 	case hwmon_curr:
1313 		switch (attr) {
1314 		case hwmon_curr_label:
1315 			*str = "bias";
1316 			return 0;
1317 		default:
1318 			return -EOPNOTSUPP;
1319 		}
1320 		break;
1321 	case hwmon_temp:
1322 		switch (attr) {
1323 		case hwmon_temp_label:
1324 			*str = "temperature";
1325 			return 0;
1326 		default:
1327 			return -EOPNOTSUPP;
1328 		}
1329 		break;
1330 	case hwmon_in:
1331 		switch (attr) {
1332 		case hwmon_in_label:
1333 			*str = "VCC";
1334 			return 0;
1335 		default:
1336 			return -EOPNOTSUPP;
1337 		}
1338 		break;
1339 	case hwmon_power:
1340 		switch (attr) {
1341 		case hwmon_power_label:
1342 			*str = sfp_hwmon_power_labels[channel];
1343 			return 0;
1344 		default:
1345 			return -EOPNOTSUPP;
1346 		}
1347 		break;
1348 	default:
1349 		return -EOPNOTSUPP;
1350 	}
1351 
1352 	return -EOPNOTSUPP;
1353 }
1354 
1355 static const struct hwmon_ops sfp_hwmon_ops = {
1356 	.is_visible = sfp_hwmon_is_visible,
1357 	.read = sfp_hwmon_read,
1358 	.read_string = sfp_hwmon_read_string,
1359 };
1360 
1361 static const struct hwmon_channel_info *sfp_hwmon_info[] = {
1362 	HWMON_CHANNEL_INFO(chip,
1363 			   HWMON_C_REGISTER_TZ),
1364 	HWMON_CHANNEL_INFO(in,
1365 			   HWMON_I_INPUT |
1366 			   HWMON_I_MAX | HWMON_I_MIN |
1367 			   HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1368 			   HWMON_I_CRIT | HWMON_I_LCRIT |
1369 			   HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1370 			   HWMON_I_LABEL),
1371 	HWMON_CHANNEL_INFO(temp,
1372 			   HWMON_T_INPUT |
1373 			   HWMON_T_MAX | HWMON_T_MIN |
1374 			   HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1375 			   HWMON_T_CRIT | HWMON_T_LCRIT |
1376 			   HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1377 			   HWMON_T_LABEL),
1378 	HWMON_CHANNEL_INFO(curr,
1379 			   HWMON_C_INPUT |
1380 			   HWMON_C_MAX | HWMON_C_MIN |
1381 			   HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1382 			   HWMON_C_CRIT | HWMON_C_LCRIT |
1383 			   HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1384 			   HWMON_C_LABEL),
1385 	HWMON_CHANNEL_INFO(power,
1386 			   /* Transmit power */
1387 			   HWMON_P_INPUT |
1388 			   HWMON_P_MAX | HWMON_P_MIN |
1389 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1390 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1391 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1392 			   HWMON_P_LABEL,
1393 			   /* Receive power */
1394 			   HWMON_P_INPUT |
1395 			   HWMON_P_MAX | HWMON_P_MIN |
1396 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1397 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1398 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1399 			   HWMON_P_LABEL),
1400 	NULL,
1401 };
1402 
1403 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1404 	.ops = &sfp_hwmon_ops,
1405 	.info = sfp_hwmon_info,
1406 };
1407 
1408 static void sfp_hwmon_probe(struct work_struct *work)
1409 {
1410 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1411 	int err;
1412 
1413 	/* hwmon interface needs to access 16bit registers in atomic way to
1414 	 * guarantee coherency of the diagnostic monitoring data. If it is not
1415 	 * possible to guarantee coherency because EEPROM is broken in such way
1416 	 * that does not support atomic 16bit read operation then we have to
1417 	 * skip registration of hwmon device.
1418 	 */
1419 	if (sfp->i2c_block_size < 2) {
1420 		dev_info(sfp->dev,
1421 			 "skipping hwmon device registration due to broken EEPROM\n");
1422 		dev_info(sfp->dev,
1423 			 "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
1424 		return;
1425 	}
1426 
1427 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1428 	if (err < 0) {
1429 		if (sfp->hwmon_tries--) {
1430 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1431 					 T_PROBE_RETRY_SLOW);
1432 		} else {
1433 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
1434 				 ERR_PTR(err));
1435 		}
1436 		return;
1437 	}
1438 
1439 	sfp->hwmon_name = hwmon_sanitize_name(dev_name(sfp->dev));
1440 	if (IS_ERR(sfp->hwmon_name)) {
1441 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1442 		return;
1443 	}
1444 
1445 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1446 							 sfp->hwmon_name, sfp,
1447 							 &sfp_hwmon_chip_info,
1448 							 NULL);
1449 	if (IS_ERR(sfp->hwmon_dev))
1450 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1451 			PTR_ERR(sfp->hwmon_dev));
1452 }
1453 
1454 static int sfp_hwmon_insert(struct sfp *sfp)
1455 {
1456 	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
1457 		return 0;
1458 
1459 	if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
1460 		return 0;
1461 
1462 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
1463 		/* This driver in general does not support address
1464 		 * change.
1465 		 */
1466 		return 0;
1467 
1468 	mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1469 	sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1470 
1471 	return 0;
1472 }
1473 
1474 static void sfp_hwmon_remove(struct sfp *sfp)
1475 {
1476 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1477 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1478 		hwmon_device_unregister(sfp->hwmon_dev);
1479 		sfp->hwmon_dev = NULL;
1480 		kfree(sfp->hwmon_name);
1481 	}
1482 }
1483 
1484 static int sfp_hwmon_init(struct sfp *sfp)
1485 {
1486 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1487 
1488 	return 0;
1489 }
1490 
1491 static void sfp_hwmon_exit(struct sfp *sfp)
1492 {
1493 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1494 }
1495 #else
1496 static int sfp_hwmon_insert(struct sfp *sfp)
1497 {
1498 	return 0;
1499 }
1500 
1501 static void sfp_hwmon_remove(struct sfp *sfp)
1502 {
1503 }
1504 
1505 static int sfp_hwmon_init(struct sfp *sfp)
1506 {
1507 	return 0;
1508 }
1509 
1510 static void sfp_hwmon_exit(struct sfp *sfp)
1511 {
1512 }
1513 #endif
1514 
1515 /* Helpers */
1516 static void sfp_module_tx_disable(struct sfp *sfp)
1517 {
1518 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1519 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1520 	sfp->state |= SFP_F_TX_DISABLE;
1521 	sfp_set_state(sfp, sfp->state);
1522 }
1523 
1524 static void sfp_module_tx_enable(struct sfp *sfp)
1525 {
1526 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1527 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1528 	sfp->state &= ~SFP_F_TX_DISABLE;
1529 	sfp_set_state(sfp, sfp->state);
1530 }
1531 
1532 #if IS_ENABLED(CONFIG_DEBUG_FS)
1533 static int sfp_debug_state_show(struct seq_file *s, void *data)
1534 {
1535 	struct sfp *sfp = s->private;
1536 
1537 	seq_printf(s, "Module state: %s\n",
1538 		   mod_state_to_str(sfp->sm_mod_state));
1539 	seq_printf(s, "Module probe attempts: %d %d\n",
1540 		   R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
1541 		   R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
1542 	seq_printf(s, "Device state: %s\n",
1543 		   dev_state_to_str(sfp->sm_dev_state));
1544 	seq_printf(s, "Main state: %s\n",
1545 		   sm_state_to_str(sfp->sm_state));
1546 	seq_printf(s, "Fault recovery remaining retries: %d\n",
1547 		   sfp->sm_fault_retries);
1548 	seq_printf(s, "PHY probe remaining retries: %d\n",
1549 		   sfp->sm_phy_retries);
1550 	seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
1551 	seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
1552 	seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
1553 	seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
1554 	return 0;
1555 }
1556 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
1557 
1558 static void sfp_debugfs_init(struct sfp *sfp)
1559 {
1560 	sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
1561 
1562 	debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
1563 			    &sfp_debug_state_fops);
1564 }
1565 
1566 static void sfp_debugfs_exit(struct sfp *sfp)
1567 {
1568 	debugfs_remove_recursive(sfp->debugfs_dir);
1569 }
1570 #else
1571 static void sfp_debugfs_init(struct sfp *sfp)
1572 {
1573 }
1574 
1575 static void sfp_debugfs_exit(struct sfp *sfp)
1576 {
1577 }
1578 #endif
1579 
1580 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1581 {
1582 	unsigned int state = sfp->state;
1583 
1584 	if (state & SFP_F_TX_DISABLE)
1585 		return;
1586 
1587 	sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1588 
1589 	udelay(T_RESET_US);
1590 
1591 	sfp_set_state(sfp, state);
1592 }
1593 
1594 /* SFP state machine */
1595 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1596 {
1597 	if (timeout)
1598 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1599 				 timeout);
1600 	else
1601 		cancel_delayed_work(&sfp->timeout);
1602 }
1603 
1604 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1605 			unsigned int timeout)
1606 {
1607 	sfp->sm_state = state;
1608 	sfp_sm_set_timer(sfp, timeout);
1609 }
1610 
1611 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1612 			    unsigned int timeout)
1613 {
1614 	sfp->sm_mod_state = state;
1615 	sfp_sm_set_timer(sfp, timeout);
1616 }
1617 
1618 static void sfp_sm_phy_detach(struct sfp *sfp)
1619 {
1620 	sfp_remove_phy(sfp->sfp_bus);
1621 	phy_device_remove(sfp->mod_phy);
1622 	phy_device_free(sfp->mod_phy);
1623 	sfp->mod_phy = NULL;
1624 }
1625 
1626 static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
1627 {
1628 	struct phy_device *phy;
1629 	int err;
1630 
1631 	phy = get_phy_device(sfp->i2c_mii, addr, is_c45);
1632 	if (phy == ERR_PTR(-ENODEV))
1633 		return PTR_ERR(phy);
1634 	if (IS_ERR(phy)) {
1635 		dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
1636 		return PTR_ERR(phy);
1637 	}
1638 
1639 	err = phy_device_register(phy);
1640 	if (err) {
1641 		phy_device_free(phy);
1642 		dev_err(sfp->dev, "phy_device_register failed: %pe\n",
1643 			ERR_PTR(err));
1644 		return err;
1645 	}
1646 
1647 	err = sfp_add_phy(sfp->sfp_bus, phy);
1648 	if (err) {
1649 		phy_device_remove(phy);
1650 		phy_device_free(phy);
1651 		dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
1652 		return err;
1653 	}
1654 
1655 	sfp->mod_phy = phy;
1656 
1657 	return 0;
1658 }
1659 
1660 static void sfp_sm_link_up(struct sfp *sfp)
1661 {
1662 	sfp_link_up(sfp->sfp_bus);
1663 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1664 }
1665 
1666 static void sfp_sm_link_down(struct sfp *sfp)
1667 {
1668 	sfp_link_down(sfp->sfp_bus);
1669 }
1670 
1671 static void sfp_sm_link_check_los(struct sfp *sfp)
1672 {
1673 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1674 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1675 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1676 	bool los = false;
1677 
1678 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1679 	 * are set, we assume that no LOS signal is available. If both are
1680 	 * set, we assume LOS is not implemented (and is meaningless.)
1681 	 */
1682 	if (los_options == los_inverted)
1683 		los = !(sfp->state & SFP_F_LOS);
1684 	else if (los_options == los_normal)
1685 		los = !!(sfp->state & SFP_F_LOS);
1686 
1687 	if (los)
1688 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1689 	else
1690 		sfp_sm_link_up(sfp);
1691 }
1692 
1693 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1694 {
1695 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1696 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1697 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1698 
1699 	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
1700 	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
1701 }
1702 
1703 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1704 {
1705 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1706 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1707 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1708 
1709 	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
1710 	       (los_options == los_normal && event == SFP_E_LOS_LOW);
1711 }
1712 
1713 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1714 {
1715 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
1716 		dev_err(sfp->dev,
1717 			"module persistently indicates fault, disabling\n");
1718 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1719 	} else {
1720 		if (warn)
1721 			dev_err(sfp->dev, "module transmit fault indicated\n");
1722 
1723 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1724 	}
1725 }
1726 
1727 static int sfp_sm_add_mdio_bus(struct sfp *sfp)
1728 {
1729 	if (sfp->mdio_protocol != MDIO_I2C_NONE)
1730 		return sfp_i2c_mdiobus_create(sfp);
1731 
1732 	return 0;
1733 }
1734 
1735 /* Probe a SFP for a PHY device if the module supports copper - the PHY
1736  * normally sits at I2C bus address 0x56, and may either be a clause 22
1737  * or clause 45 PHY.
1738  *
1739  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
1740  * negotiation enabled, but some may be in 1000base-X - which is for the
1741  * PHY driver to determine.
1742  *
1743  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
1744  * mode according to the negotiated line speed.
1745  */
1746 static int sfp_sm_probe_for_phy(struct sfp *sfp)
1747 {
1748 	int err = 0;
1749 
1750 	switch (sfp->mdio_protocol) {
1751 	case MDIO_I2C_NONE:
1752 		break;
1753 
1754 	case MDIO_I2C_MARVELL_C22:
1755 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, false);
1756 		break;
1757 
1758 	case MDIO_I2C_C45:
1759 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, true);
1760 		break;
1761 
1762 	case MDIO_I2C_ROLLBALL:
1763 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR_ROLLBALL, true);
1764 		break;
1765 	}
1766 
1767 	return err;
1768 }
1769 
1770 static int sfp_module_parse_power(struct sfp *sfp)
1771 {
1772 	u32 power_mW = 1000;
1773 	bool supports_a2;
1774 
1775 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
1776 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1777 		power_mW = 1500;
1778 	/* Added in Rev 11.9, but there is no compliance code for this */
1779 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV11_4 &&
1780 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1781 		power_mW = 2000;
1782 
1783 	/* Power level 1 modules (max. 1W) are always supported. */
1784 	if (power_mW <= 1000) {
1785 		sfp->module_power_mW = power_mW;
1786 		return 0;
1787 	}
1788 
1789 	supports_a2 = sfp->id.ext.sff8472_compliance !=
1790 				SFP_SFF8472_COMPLIANCE_NONE ||
1791 		      sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
1792 
1793 	if (power_mW > sfp->max_power_mW) {
1794 		/* Module power specification exceeds the allowed maximum. */
1795 		if (!supports_a2) {
1796 			/* The module appears not to implement bus address
1797 			 * 0xa2, so assume that the module powers up in the
1798 			 * indicated mode.
1799 			 */
1800 			dev_err(sfp->dev,
1801 				"Host does not support %u.%uW modules\n",
1802 				power_mW / 1000, (power_mW / 100) % 10);
1803 			return -EINVAL;
1804 		} else {
1805 			dev_warn(sfp->dev,
1806 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1807 				 power_mW / 1000, (power_mW / 100) % 10);
1808 			return 0;
1809 		}
1810 	}
1811 
1812 	if (!supports_a2) {
1813 		/* The module power level is below the host maximum and the
1814 		 * module appears not to implement bus address 0xa2, so assume
1815 		 * that the module powers up in the indicated mode.
1816 		 */
1817 		return 0;
1818 	}
1819 
1820 	/* If the module requires a higher power mode, but also requires
1821 	 * an address change sequence, warn the user that the module may
1822 	 * not be functional.
1823 	 */
1824 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
1825 		dev_warn(sfp->dev,
1826 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1827 			 power_mW / 1000, (power_mW / 100) % 10);
1828 		return 0;
1829 	}
1830 
1831 	sfp->module_power_mW = power_mW;
1832 
1833 	return 0;
1834 }
1835 
1836 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1837 {
1838 	int err;
1839 
1840 	err = sfp_modify_u8(sfp, true, SFP_EXT_STATUS,
1841 			    SFP_EXT_STATUS_PWRLVL_SELECT,
1842 			    enable ? SFP_EXT_STATUS_PWRLVL_SELECT : 0);
1843 	if (err != sizeof(u8)) {
1844 		dev_err(sfp->dev, "failed to %sable high power: %pe\n",
1845 			enable ? "en" : "dis", ERR_PTR(err));
1846 		return -EAGAIN;
1847 	}
1848 
1849 	if (enable)
1850 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1851 			 sfp->module_power_mW / 1000,
1852 			 (sfp->module_power_mW / 100) % 10);
1853 
1854 	return 0;
1855 }
1856 
1857 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
1858  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
1859  * not support multibyte reads from the EEPROM. Each multi-byte read
1860  * operation returns just one byte of EEPROM followed by zeros. There is
1861  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
1862  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
1863  * name and vendor id into EEPROM, so there is even no way to detect if
1864  * module is V-SOL V2801F. Therefore check for those zeros in the read
1865  * data and then based on check switch to reading EEPROM to one byte
1866  * at a time.
1867  */
1868 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
1869 {
1870 	size_t i, block_size = sfp->i2c_block_size;
1871 
1872 	/* Already using byte IO */
1873 	if (block_size == 1)
1874 		return false;
1875 
1876 	for (i = 1; i < len; i += block_size) {
1877 		if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
1878 			return false;
1879 	}
1880 	return true;
1881 }
1882 
1883 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
1884 {
1885 	u8 check;
1886 	int err;
1887 
1888 	if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
1889 	    id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
1890 	    id->base.connector != SFF8024_CONNECTOR_LC) {
1891 		dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
1892 		id->base.phys_id = SFF8024_ID_SFF_8472;
1893 		id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
1894 		id->base.connector = SFF8024_CONNECTOR_LC;
1895 		err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
1896 		if (err != 3) {
1897 			dev_err(sfp->dev,
1898 				"Failed to rewrite module EEPROM: %pe\n",
1899 				ERR_PTR(err));
1900 			return err;
1901 		}
1902 
1903 		/* Cotsworks modules have been found to require a delay between write operations. */
1904 		mdelay(50);
1905 
1906 		/* Update base structure checksum */
1907 		check = sfp_check(&id->base, sizeof(id->base) - 1);
1908 		err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
1909 		if (err != 1) {
1910 			dev_err(sfp->dev,
1911 				"Failed to update base structure checksum in fiber module EEPROM: %pe\n",
1912 				ERR_PTR(err));
1913 			return err;
1914 		}
1915 	}
1916 	return 0;
1917 }
1918 
1919 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
1920 {
1921 	/* SFP module inserted - read I2C data */
1922 	struct sfp_eeprom_id id;
1923 	bool cotsworks_sfbg;
1924 	bool cotsworks;
1925 	u8 check;
1926 	int ret;
1927 
1928 	/* Some SFP modules and also some Linux I2C drivers do not like reads
1929 	 * longer than 16 bytes, so read the EEPROM in chunks of 16 bytes at
1930 	 * a time.
1931 	 */
1932 	sfp->i2c_block_size = 16;
1933 
1934 	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
1935 	if (ret < 0) {
1936 		if (report)
1937 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
1938 				ERR_PTR(ret));
1939 		return -EAGAIN;
1940 	}
1941 
1942 	if (ret != sizeof(id.base)) {
1943 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
1944 		return -EAGAIN;
1945 	}
1946 
1947 	/* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
1948 	 * address 0x51 is just one byte at a time. Also SFF-8472 requires
1949 	 * that EEPROM supports atomic 16bit read operation for diagnostic
1950 	 * fields, so do not switch to one byte reading at a time unless it
1951 	 * is really required and we have no other option.
1952 	 */
1953 	if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
1954 		dev_info(sfp->dev,
1955 			 "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
1956 		dev_info(sfp->dev,
1957 			 "Switching to reading EEPROM to one byte at a time\n");
1958 		sfp->i2c_block_size = 1;
1959 
1960 		ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
1961 		if (ret < 0) {
1962 			if (report)
1963 				dev_err(sfp->dev,
1964 					"failed to read EEPROM: %pe\n",
1965 					ERR_PTR(ret));
1966 			return -EAGAIN;
1967 		}
1968 
1969 		if (ret != sizeof(id.base)) {
1970 			dev_err(sfp->dev, "EEPROM short read: %pe\n",
1971 				ERR_PTR(ret));
1972 			return -EAGAIN;
1973 		}
1974 	}
1975 
1976 	/* Cotsworks do not seem to update the checksums when they
1977 	 * do the final programming with the final module part number,
1978 	 * serial number and date code.
1979 	 */
1980 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
1981 	cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
1982 
1983 	/* Cotsworks SFF module EEPROM do not always have valid phys_id,
1984 	 * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
1985 	 * Cotsworks PN matches and bytes are not correct.
1986 	 */
1987 	if (cotsworks && cotsworks_sfbg) {
1988 		ret = sfp_cotsworks_fixup_check(sfp, &id);
1989 		if (ret < 0)
1990 			return ret;
1991 	}
1992 
1993 	/* Validate the checksum over the base structure */
1994 	check = sfp_check(&id.base, sizeof(id.base) - 1);
1995 	if (check != id.base.cc_base) {
1996 		if (cotsworks) {
1997 			dev_warn(sfp->dev,
1998 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
1999 				 check, id.base.cc_base);
2000 		} else {
2001 			dev_err(sfp->dev,
2002 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
2003 				check, id.base.cc_base);
2004 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2005 				       16, 1, &id, sizeof(id), true);
2006 			return -EINVAL;
2007 		}
2008 	}
2009 
2010 	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
2011 	if (ret < 0) {
2012 		if (report)
2013 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2014 				ERR_PTR(ret));
2015 		return -EAGAIN;
2016 	}
2017 
2018 	if (ret != sizeof(id.ext)) {
2019 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2020 		return -EAGAIN;
2021 	}
2022 
2023 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
2024 	if (check != id.ext.cc_ext) {
2025 		if (cotsworks) {
2026 			dev_warn(sfp->dev,
2027 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
2028 				 check, id.ext.cc_ext);
2029 		} else {
2030 			dev_err(sfp->dev,
2031 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
2032 				check, id.ext.cc_ext);
2033 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2034 				       16, 1, &id, sizeof(id), true);
2035 			memset(&id.ext, 0, sizeof(id.ext));
2036 		}
2037 	}
2038 
2039 	sfp->id = id;
2040 
2041 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
2042 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
2043 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
2044 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
2045 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
2046 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
2047 
2048 	/* Check whether we support this module */
2049 	if (!sfp->type->module_supported(&id)) {
2050 		dev_err(sfp->dev,
2051 			"module is not supported - phys id 0x%02x 0x%02x\n",
2052 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
2053 		return -EINVAL;
2054 	}
2055 
2056 	/* If the module requires address swap mode, warn about it */
2057 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
2058 		dev_warn(sfp->dev,
2059 			 "module address swap to access page 0xA2 is not supported.\n");
2060 
2061 	/* Parse the module power requirement */
2062 	ret = sfp_module_parse_power(sfp);
2063 	if (ret < 0)
2064 		return ret;
2065 
2066 	/* Initialise state bits to use from hardware */
2067 	sfp->state_hw_mask = SFP_F_PRESENT;
2068 	if (sfp->gpio[GPIO_TX_DISABLE])
2069 		sfp->state_hw_mask |= SFP_F_TX_DISABLE;
2070 	if (sfp->gpio[GPIO_TX_FAULT])
2071 		sfp->state_hw_mask |= SFP_F_TX_FAULT;
2072 	if (sfp->gpio[GPIO_LOS])
2073 		sfp->state_hw_mask |= SFP_F_LOS;
2074 
2075 	sfp->module_t_start_up = T_START_UP;
2076 	sfp->module_t_wait = T_WAIT;
2077 
2078 	sfp->tx_fault_ignore = false;
2079 
2080 	if (sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SFI ||
2081 	    sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SR ||
2082 	    sfp->id.base.extended_cc == SFF8024_ECC_5GBASE_T ||
2083 	    sfp->id.base.extended_cc == SFF8024_ECC_2_5GBASE_T)
2084 		sfp->mdio_protocol = MDIO_I2C_C45;
2085 	else if (sfp->id.base.e1000_base_t)
2086 		sfp->mdio_protocol = MDIO_I2C_MARVELL_C22;
2087 	else
2088 		sfp->mdio_protocol = MDIO_I2C_NONE;
2089 
2090 	sfp->quirk = sfp_lookup_quirk(&id);
2091 	if (sfp->quirk && sfp->quirk->fixup)
2092 		sfp->quirk->fixup(sfp);
2093 
2094 	return 0;
2095 }
2096 
2097 static void sfp_sm_mod_remove(struct sfp *sfp)
2098 {
2099 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
2100 		sfp_module_remove(sfp->sfp_bus);
2101 
2102 	sfp_hwmon_remove(sfp);
2103 
2104 	memset(&sfp->id, 0, sizeof(sfp->id));
2105 	sfp->module_power_mW = 0;
2106 
2107 	dev_info(sfp->dev, "module removed\n");
2108 }
2109 
2110 /* This state machine tracks the upstream's state */
2111 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
2112 {
2113 	switch (sfp->sm_dev_state) {
2114 	default:
2115 		if (event == SFP_E_DEV_ATTACH)
2116 			sfp->sm_dev_state = SFP_DEV_DOWN;
2117 		break;
2118 
2119 	case SFP_DEV_DOWN:
2120 		if (event == SFP_E_DEV_DETACH)
2121 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2122 		else if (event == SFP_E_DEV_UP)
2123 			sfp->sm_dev_state = SFP_DEV_UP;
2124 		break;
2125 
2126 	case SFP_DEV_UP:
2127 		if (event == SFP_E_DEV_DETACH)
2128 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2129 		else if (event == SFP_E_DEV_DOWN)
2130 			sfp->sm_dev_state = SFP_DEV_DOWN;
2131 		break;
2132 	}
2133 }
2134 
2135 /* This state machine tracks the insert/remove state of the module, probes
2136  * the on-board EEPROM, and sets up the power level.
2137  */
2138 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
2139 {
2140 	int err;
2141 
2142 	/* Handle remove event globally, it resets this state machine */
2143 	if (event == SFP_E_REMOVE) {
2144 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
2145 			sfp_sm_mod_remove(sfp);
2146 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
2147 		return;
2148 	}
2149 
2150 	/* Handle device detach globally */
2151 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
2152 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
2153 		if (sfp->module_power_mW > 1000 &&
2154 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
2155 			sfp_sm_mod_hpower(sfp, false);
2156 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2157 		return;
2158 	}
2159 
2160 	switch (sfp->sm_mod_state) {
2161 	default:
2162 		if (event == SFP_E_INSERT) {
2163 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
2164 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
2165 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
2166 		}
2167 		break;
2168 
2169 	case SFP_MOD_PROBE:
2170 		/* Wait for T_PROBE_INIT to time out */
2171 		if (event != SFP_E_TIMEOUT)
2172 			break;
2173 
2174 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
2175 		if (err == -EAGAIN) {
2176 			if (sfp->sm_mod_tries_init &&
2177 			   --sfp->sm_mod_tries_init) {
2178 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2179 				break;
2180 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
2181 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
2182 					dev_warn(sfp->dev,
2183 						 "please wait, module slow to respond\n");
2184 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
2185 				break;
2186 			}
2187 		}
2188 		if (err < 0) {
2189 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2190 			break;
2191 		}
2192 
2193 		/* Force a poll to re-read the hardware signal state after
2194 		 * sfp_sm_mod_probe() changed state_hw_mask.
2195 		 */
2196 		mod_delayed_work(system_wq, &sfp->poll, 1);
2197 
2198 		err = sfp_hwmon_insert(sfp);
2199 		if (err)
2200 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
2201 				 ERR_PTR(err));
2202 
2203 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2204 		fallthrough;
2205 	case SFP_MOD_WAITDEV:
2206 		/* Ensure that the device is attached before proceeding */
2207 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
2208 			break;
2209 
2210 		/* Report the module insertion to the upstream device */
2211 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id,
2212 					sfp->quirk);
2213 		if (err < 0) {
2214 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2215 			break;
2216 		}
2217 
2218 		/* If this is a power level 1 module, we are done */
2219 		if (sfp->module_power_mW <= 1000)
2220 			goto insert;
2221 
2222 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
2223 		fallthrough;
2224 	case SFP_MOD_HPOWER:
2225 		/* Enable high power mode */
2226 		err = sfp_sm_mod_hpower(sfp, true);
2227 		if (err < 0) {
2228 			if (err != -EAGAIN) {
2229 				sfp_module_remove(sfp->sfp_bus);
2230 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2231 			} else {
2232 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2233 			}
2234 			break;
2235 		}
2236 
2237 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
2238 		break;
2239 
2240 	case SFP_MOD_WAITPWR:
2241 		/* Wait for T_HPOWER_LEVEL to time out */
2242 		if (event != SFP_E_TIMEOUT)
2243 			break;
2244 
2245 	insert:
2246 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
2247 		break;
2248 
2249 	case SFP_MOD_PRESENT:
2250 	case SFP_MOD_ERROR:
2251 		break;
2252 	}
2253 }
2254 
2255 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
2256 {
2257 	unsigned long timeout;
2258 	int ret;
2259 
2260 	/* Some events are global */
2261 	if (sfp->sm_state != SFP_S_DOWN &&
2262 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2263 	     sfp->sm_dev_state != SFP_DEV_UP)) {
2264 		if (sfp->sm_state == SFP_S_LINK_UP &&
2265 		    sfp->sm_dev_state == SFP_DEV_UP)
2266 			sfp_sm_link_down(sfp);
2267 		if (sfp->sm_state > SFP_S_INIT)
2268 			sfp_module_stop(sfp->sfp_bus);
2269 		if (sfp->mod_phy)
2270 			sfp_sm_phy_detach(sfp);
2271 		if (sfp->i2c_mii)
2272 			sfp_i2c_mdiobus_destroy(sfp);
2273 		sfp_module_tx_disable(sfp);
2274 		sfp_soft_stop_poll(sfp);
2275 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
2276 		return;
2277 	}
2278 
2279 	/* The main state machine */
2280 	switch (sfp->sm_state) {
2281 	case SFP_S_DOWN:
2282 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2283 		    sfp->sm_dev_state != SFP_DEV_UP)
2284 			break;
2285 
2286 		if (!(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE))
2287 			sfp_soft_start_poll(sfp);
2288 
2289 		sfp_module_tx_enable(sfp);
2290 
2291 		/* Initialise the fault clearance retries */
2292 		sfp->sm_fault_retries = N_FAULT_INIT;
2293 
2294 		/* We need to check the TX_FAULT state, which is not defined
2295 		 * while TX_DISABLE is asserted. The earliest we want to do
2296 		 * anything (such as probe for a PHY) is 50ms (or more on
2297 		 * specific modules).
2298 		 */
2299 		sfp_sm_next(sfp, SFP_S_WAIT, sfp->module_t_wait);
2300 		break;
2301 
2302 	case SFP_S_WAIT:
2303 		if (event != SFP_E_TIMEOUT)
2304 			break;
2305 
2306 		if (sfp->state & SFP_F_TX_FAULT) {
2307 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
2308 			 * from the TX_DISABLE deassertion for the module to
2309 			 * initialise, which is indicated by TX_FAULT
2310 			 * deasserting.
2311 			 */
2312 			timeout = sfp->module_t_start_up;
2313 			if (timeout > sfp->module_t_wait)
2314 				timeout -= sfp->module_t_wait;
2315 			else
2316 				timeout = 1;
2317 
2318 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
2319 		} else {
2320 			/* TX_FAULT is not asserted, assume the module has
2321 			 * finished initialising.
2322 			 */
2323 			goto init_done;
2324 		}
2325 		break;
2326 
2327 	case SFP_S_INIT:
2328 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2329 			/* TX_FAULT is still asserted after t_init
2330 			 * or t_start_up, so assume there is a fault.
2331 			 */
2332 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
2333 				     sfp->sm_fault_retries == N_FAULT_INIT);
2334 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2335 	init_done:
2336 			/* Create mdiobus and start trying for PHY */
2337 			ret = sfp_sm_add_mdio_bus(sfp);
2338 			if (ret < 0) {
2339 				sfp_sm_next(sfp, SFP_S_FAIL, 0);
2340 				break;
2341 			}
2342 			sfp->sm_phy_retries = R_PHY_RETRY;
2343 			goto phy_probe;
2344 		}
2345 		break;
2346 
2347 	case SFP_S_INIT_PHY:
2348 		if (event != SFP_E_TIMEOUT)
2349 			break;
2350 	phy_probe:
2351 		/* TX_FAULT deasserted or we timed out with TX_FAULT
2352 		 * clear.  Probe for the PHY and check the LOS state.
2353 		 */
2354 		ret = sfp_sm_probe_for_phy(sfp);
2355 		if (ret == -ENODEV) {
2356 			if (--sfp->sm_phy_retries) {
2357 				sfp_sm_next(sfp, SFP_S_INIT_PHY, T_PHY_RETRY);
2358 				break;
2359 			} else {
2360 				dev_info(sfp->dev, "no PHY detected\n");
2361 			}
2362 		} else if (ret) {
2363 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2364 			break;
2365 		}
2366 		if (sfp_module_start(sfp->sfp_bus)) {
2367 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2368 			break;
2369 		}
2370 		sfp_sm_link_check_los(sfp);
2371 
2372 		/* Reset the fault retry count */
2373 		sfp->sm_fault_retries = N_FAULT;
2374 		break;
2375 
2376 	case SFP_S_INIT_TX_FAULT:
2377 		if (event == SFP_E_TIMEOUT) {
2378 			sfp_module_tx_fault_reset(sfp);
2379 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
2380 		}
2381 		break;
2382 
2383 	case SFP_S_WAIT_LOS:
2384 		if (event == SFP_E_TX_FAULT)
2385 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2386 		else if (sfp_los_event_inactive(sfp, event))
2387 			sfp_sm_link_up(sfp);
2388 		break;
2389 
2390 	case SFP_S_LINK_UP:
2391 		if (event == SFP_E_TX_FAULT) {
2392 			sfp_sm_link_down(sfp);
2393 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2394 		} else if (sfp_los_event_active(sfp, event)) {
2395 			sfp_sm_link_down(sfp);
2396 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2397 		}
2398 		break;
2399 
2400 	case SFP_S_TX_FAULT:
2401 		if (event == SFP_E_TIMEOUT) {
2402 			sfp_module_tx_fault_reset(sfp);
2403 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2404 		}
2405 		break;
2406 
2407 	case SFP_S_REINIT:
2408 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2409 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2410 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2411 			dev_info(sfp->dev, "module transmit fault recovered\n");
2412 			sfp_sm_link_check_los(sfp);
2413 		}
2414 		break;
2415 
2416 	case SFP_S_TX_DISABLE:
2417 		break;
2418 	}
2419 }
2420 
2421 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
2422 {
2423 	mutex_lock(&sfp->sm_mutex);
2424 
2425 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
2426 		mod_state_to_str(sfp->sm_mod_state),
2427 		dev_state_to_str(sfp->sm_dev_state),
2428 		sm_state_to_str(sfp->sm_state),
2429 		event_to_str(event));
2430 
2431 	sfp_sm_device(sfp, event);
2432 	sfp_sm_module(sfp, event);
2433 	sfp_sm_main(sfp, event);
2434 
2435 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
2436 		mod_state_to_str(sfp->sm_mod_state),
2437 		dev_state_to_str(sfp->sm_dev_state),
2438 		sm_state_to_str(sfp->sm_state));
2439 
2440 	mutex_unlock(&sfp->sm_mutex);
2441 }
2442 
2443 static void sfp_attach(struct sfp *sfp)
2444 {
2445 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
2446 }
2447 
2448 static void sfp_detach(struct sfp *sfp)
2449 {
2450 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
2451 }
2452 
2453 static void sfp_start(struct sfp *sfp)
2454 {
2455 	sfp_sm_event(sfp, SFP_E_DEV_UP);
2456 }
2457 
2458 static void sfp_stop(struct sfp *sfp)
2459 {
2460 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
2461 }
2462 
2463 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2464 {
2465 	/* locking... and check module is present */
2466 
2467 	if (sfp->id.ext.sff8472_compliance &&
2468 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2469 		modinfo->type = ETH_MODULE_SFF_8472;
2470 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2471 	} else {
2472 		modinfo->type = ETH_MODULE_SFF_8079;
2473 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2474 	}
2475 	return 0;
2476 }
2477 
2478 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2479 			     u8 *data)
2480 {
2481 	unsigned int first, last, len;
2482 	int ret;
2483 
2484 	if (ee->len == 0)
2485 		return -EINVAL;
2486 
2487 	first = ee->offset;
2488 	last = ee->offset + ee->len;
2489 	if (first < ETH_MODULE_SFF_8079_LEN) {
2490 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2491 		len -= first;
2492 
2493 		ret = sfp_read(sfp, false, first, data, len);
2494 		if (ret < 0)
2495 			return ret;
2496 
2497 		first += len;
2498 		data += len;
2499 	}
2500 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2501 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2502 		len -= first;
2503 		first -= ETH_MODULE_SFF_8079_LEN;
2504 
2505 		ret = sfp_read(sfp, true, first, data, len);
2506 		if (ret < 0)
2507 			return ret;
2508 	}
2509 	return 0;
2510 }
2511 
2512 static int sfp_module_eeprom_by_page(struct sfp *sfp,
2513 				     const struct ethtool_module_eeprom *page,
2514 				     struct netlink_ext_ack *extack)
2515 {
2516 	if (page->bank) {
2517 		NL_SET_ERR_MSG(extack, "Banks not supported");
2518 		return -EOPNOTSUPP;
2519 	}
2520 
2521 	if (page->page) {
2522 		NL_SET_ERR_MSG(extack, "Only page 0 supported");
2523 		return -EOPNOTSUPP;
2524 	}
2525 
2526 	if (page->i2c_address != 0x50 &&
2527 	    page->i2c_address != 0x51) {
2528 		NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
2529 		return -EOPNOTSUPP;
2530 	}
2531 
2532 	return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
2533 			page->data, page->length);
2534 };
2535 
2536 static const struct sfp_socket_ops sfp_module_ops = {
2537 	.attach = sfp_attach,
2538 	.detach = sfp_detach,
2539 	.start = sfp_start,
2540 	.stop = sfp_stop,
2541 	.module_info = sfp_module_info,
2542 	.module_eeprom = sfp_module_eeprom,
2543 	.module_eeprom_by_page = sfp_module_eeprom_by_page,
2544 };
2545 
2546 static void sfp_timeout(struct work_struct *work)
2547 {
2548 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2549 
2550 	rtnl_lock();
2551 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2552 	rtnl_unlock();
2553 }
2554 
2555 static void sfp_check_state(struct sfp *sfp)
2556 {
2557 	unsigned int state, i, changed;
2558 
2559 	mutex_lock(&sfp->st_mutex);
2560 	state = sfp_get_state(sfp);
2561 	changed = state ^ sfp->state;
2562 	if (sfp->tx_fault_ignore)
2563 		changed &= SFP_F_PRESENT | SFP_F_LOS;
2564 	else
2565 		changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2566 
2567 	for (i = 0; i < GPIO_MAX; i++)
2568 		if (changed & BIT(i))
2569 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_names[i],
2570 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2571 
2572 	state |= sfp->state & (SFP_F_TX_DISABLE | SFP_F_RATE_SELECT);
2573 	sfp->state = state;
2574 
2575 	rtnl_lock();
2576 	if (changed & SFP_F_PRESENT)
2577 		sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2578 				SFP_E_INSERT : SFP_E_REMOVE);
2579 
2580 	if (changed & SFP_F_TX_FAULT)
2581 		sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2582 				SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2583 
2584 	if (changed & SFP_F_LOS)
2585 		sfp_sm_event(sfp, state & SFP_F_LOS ?
2586 				SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2587 	rtnl_unlock();
2588 	mutex_unlock(&sfp->st_mutex);
2589 }
2590 
2591 static irqreturn_t sfp_irq(int irq, void *data)
2592 {
2593 	struct sfp *sfp = data;
2594 
2595 	sfp_check_state(sfp);
2596 
2597 	return IRQ_HANDLED;
2598 }
2599 
2600 static void sfp_poll(struct work_struct *work)
2601 {
2602 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2603 
2604 	sfp_check_state(sfp);
2605 
2606 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2607 	    sfp->need_poll)
2608 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2609 }
2610 
2611 static struct sfp *sfp_alloc(struct device *dev)
2612 {
2613 	struct sfp *sfp;
2614 
2615 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2616 	if (!sfp)
2617 		return ERR_PTR(-ENOMEM);
2618 
2619 	sfp->dev = dev;
2620 
2621 	mutex_init(&sfp->sm_mutex);
2622 	mutex_init(&sfp->st_mutex);
2623 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2624 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2625 
2626 	sfp_hwmon_init(sfp);
2627 
2628 	return sfp;
2629 }
2630 
2631 static void sfp_cleanup(void *data)
2632 {
2633 	struct sfp *sfp = data;
2634 
2635 	sfp_hwmon_exit(sfp);
2636 
2637 	cancel_delayed_work_sync(&sfp->poll);
2638 	cancel_delayed_work_sync(&sfp->timeout);
2639 	if (sfp->i2c_mii) {
2640 		mdiobus_unregister(sfp->i2c_mii);
2641 		mdiobus_free(sfp->i2c_mii);
2642 	}
2643 	if (sfp->i2c)
2644 		i2c_put_adapter(sfp->i2c);
2645 	kfree(sfp);
2646 }
2647 
2648 static int sfp_i2c_get(struct sfp *sfp)
2649 {
2650 	struct fwnode_handle *h;
2651 	struct i2c_adapter *i2c;
2652 	int err;
2653 
2654 	h = fwnode_find_reference(dev_fwnode(sfp->dev), "i2c-bus", 0);
2655 	if (IS_ERR(h)) {
2656 		dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2657 		return -ENODEV;
2658 	}
2659 
2660 	i2c = i2c_get_adapter_by_fwnode(h);
2661 	if (!i2c) {
2662 		err = -EPROBE_DEFER;
2663 		goto put;
2664 	}
2665 
2666 	err = sfp_i2c_configure(sfp, i2c);
2667 	if (err)
2668 		i2c_put_adapter(i2c);
2669 put:
2670 	fwnode_handle_put(h);
2671 	return err;
2672 }
2673 
2674 static int sfp_probe(struct platform_device *pdev)
2675 {
2676 	const struct sff_data *sff;
2677 	char *sfp_irq_name;
2678 	struct sfp *sfp;
2679 	int err, i;
2680 
2681 	sfp = sfp_alloc(&pdev->dev);
2682 	if (IS_ERR(sfp))
2683 		return PTR_ERR(sfp);
2684 
2685 	platform_set_drvdata(pdev, sfp);
2686 
2687 	err = devm_add_action_or_reset(sfp->dev, sfp_cleanup, sfp);
2688 	if (err < 0)
2689 		return err;
2690 
2691 	sff = device_get_match_data(sfp->dev);
2692 	if (!sff)
2693 		sff = &sfp_data;
2694 
2695 	sfp->type = sff;
2696 
2697 	err = sfp_i2c_get(sfp);
2698 	if (err)
2699 		return err;
2700 
2701 	for (i = 0; i < GPIO_MAX; i++)
2702 		if (sff->gpios & BIT(i)) {
2703 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
2704 					   gpio_names[i], gpio_flags[i]);
2705 			if (IS_ERR(sfp->gpio[i]))
2706 				return PTR_ERR(sfp->gpio[i]);
2707 		}
2708 
2709 	sfp->state_hw_mask = SFP_F_PRESENT;
2710 
2711 	sfp->get_state = sfp_gpio_get_state;
2712 	sfp->set_state = sfp_gpio_set_state;
2713 
2714 	/* Modules that have no detect signal are always present */
2715 	if (!(sfp->gpio[GPIO_MODDEF0]))
2716 		sfp->get_state = sff_gpio_get_state;
2717 
2718 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
2719 				 &sfp->max_power_mW);
2720 	if (sfp->max_power_mW < 1000) {
2721 		if (sfp->max_power_mW)
2722 			dev_warn(sfp->dev,
2723 				 "Firmware bug: host maximum power should be at least 1W\n");
2724 		sfp->max_power_mW = 1000;
2725 	}
2726 
2727 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
2728 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
2729 
2730 	/* Get the initial state, and always signal TX disable,
2731 	 * since the network interface will not be up.
2732 	 */
2733 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
2734 
2735 	if (sfp->gpio[GPIO_RATE_SELECT] &&
2736 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RATE_SELECT]))
2737 		sfp->state |= SFP_F_RATE_SELECT;
2738 	sfp_set_state(sfp, sfp->state);
2739 	sfp_module_tx_disable(sfp);
2740 	if (sfp->state & SFP_F_PRESENT) {
2741 		rtnl_lock();
2742 		sfp_sm_event(sfp, SFP_E_INSERT);
2743 		rtnl_unlock();
2744 	}
2745 
2746 	for (i = 0; i < GPIO_MAX; i++) {
2747 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
2748 			continue;
2749 
2750 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
2751 		if (sfp->gpio_irq[i] < 0) {
2752 			sfp->gpio_irq[i] = 0;
2753 			sfp->need_poll = true;
2754 			continue;
2755 		}
2756 
2757 		sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
2758 					      "%s-%s", dev_name(sfp->dev),
2759 					      gpio_names[i]);
2760 
2761 		if (!sfp_irq_name)
2762 			return -ENOMEM;
2763 
2764 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
2765 						NULL, sfp_irq,
2766 						IRQF_ONESHOT |
2767 						IRQF_TRIGGER_RISING |
2768 						IRQF_TRIGGER_FALLING,
2769 						sfp_irq_name, sfp);
2770 		if (err) {
2771 			sfp->gpio_irq[i] = 0;
2772 			sfp->need_poll = true;
2773 		}
2774 	}
2775 
2776 	if (sfp->need_poll)
2777 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2778 
2779 	/* We could have an issue in cases no Tx disable pin is available or
2780 	 * wired as modules using a laser as their light source will continue to
2781 	 * be active when the fiber is removed. This could be a safety issue and
2782 	 * we should at least warn the user about that.
2783 	 */
2784 	if (!sfp->gpio[GPIO_TX_DISABLE])
2785 		dev_warn(sfp->dev,
2786 			 "No tx_disable pin: SFP modules will always be emitting.\n");
2787 
2788 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
2789 	if (!sfp->sfp_bus)
2790 		return -ENOMEM;
2791 
2792 	sfp_debugfs_init(sfp);
2793 
2794 	return 0;
2795 }
2796 
2797 static int sfp_remove(struct platform_device *pdev)
2798 {
2799 	struct sfp *sfp = platform_get_drvdata(pdev);
2800 
2801 	sfp_debugfs_exit(sfp);
2802 	sfp_unregister_socket(sfp->sfp_bus);
2803 
2804 	rtnl_lock();
2805 	sfp_sm_event(sfp, SFP_E_REMOVE);
2806 	rtnl_unlock();
2807 
2808 	return 0;
2809 }
2810 
2811 static void sfp_shutdown(struct platform_device *pdev)
2812 {
2813 	struct sfp *sfp = platform_get_drvdata(pdev);
2814 	int i;
2815 
2816 	for (i = 0; i < GPIO_MAX; i++) {
2817 		if (!sfp->gpio_irq[i])
2818 			continue;
2819 
2820 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
2821 	}
2822 
2823 	cancel_delayed_work_sync(&sfp->poll);
2824 	cancel_delayed_work_sync(&sfp->timeout);
2825 }
2826 
2827 static struct platform_driver sfp_driver = {
2828 	.probe = sfp_probe,
2829 	.remove = sfp_remove,
2830 	.shutdown = sfp_shutdown,
2831 	.driver = {
2832 		.name = "sfp",
2833 		.of_match_table = sfp_of_match,
2834 	},
2835 };
2836 
2837 static int sfp_init(void)
2838 {
2839 	poll_jiffies = msecs_to_jiffies(100);
2840 
2841 	return platform_driver_register(&sfp_driver);
2842 }
2843 module_init(sfp_init);
2844 
2845 static void sfp_exit(void)
2846 {
2847 	platform_driver_unregister(&sfp_driver);
2848 }
2849 module_exit(sfp_exit);
2850 
2851 MODULE_ALIAS("platform:sfp");
2852 MODULE_AUTHOR("Russell King");
2853 MODULE_LICENSE("GPL v2");
2854