xref: /openbmc/linux/drivers/net/phy/sfp.c (revision 5859a99b)
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_RS0,
28 	GPIO_RS1,
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_RS0 = BIT(GPIO_RS0),
36 	SFP_F_RS1 = BIT(GPIO_RS1),
37 
38 	SFP_F_OUTPUTS = SFP_F_TX_DISABLE | SFP_F_RS0 | SFP_F_RS1,
39 
40 	SFP_E_INSERT = 0,
41 	SFP_E_REMOVE,
42 	SFP_E_DEV_ATTACH,
43 	SFP_E_DEV_DETACH,
44 	SFP_E_DEV_DOWN,
45 	SFP_E_DEV_UP,
46 	SFP_E_TX_FAULT,
47 	SFP_E_TX_CLEAR,
48 	SFP_E_LOS_HIGH,
49 	SFP_E_LOS_LOW,
50 	SFP_E_TIMEOUT,
51 
52 	SFP_MOD_EMPTY = 0,
53 	SFP_MOD_ERROR,
54 	SFP_MOD_PROBE,
55 	SFP_MOD_WAITDEV,
56 	SFP_MOD_HPOWER,
57 	SFP_MOD_WAITPWR,
58 	SFP_MOD_PRESENT,
59 
60 	SFP_DEV_DETACHED = 0,
61 	SFP_DEV_DOWN,
62 	SFP_DEV_UP,
63 
64 	SFP_S_DOWN = 0,
65 	SFP_S_FAIL,
66 	SFP_S_WAIT,
67 	SFP_S_INIT,
68 	SFP_S_INIT_PHY,
69 	SFP_S_INIT_TX_FAULT,
70 	SFP_S_WAIT_LOS,
71 	SFP_S_LINK_UP,
72 	SFP_S_TX_FAULT,
73 	SFP_S_REINIT,
74 	SFP_S_TX_DISABLE,
75 };
76 
77 static const char  * const mod_state_strings[] = {
78 	[SFP_MOD_EMPTY] = "empty",
79 	[SFP_MOD_ERROR] = "error",
80 	[SFP_MOD_PROBE] = "probe",
81 	[SFP_MOD_WAITDEV] = "waitdev",
82 	[SFP_MOD_HPOWER] = "hpower",
83 	[SFP_MOD_WAITPWR] = "waitpwr",
84 	[SFP_MOD_PRESENT] = "present",
85 };
86 
87 static const char *mod_state_to_str(unsigned short mod_state)
88 {
89 	if (mod_state >= ARRAY_SIZE(mod_state_strings))
90 		return "Unknown module state";
91 	return mod_state_strings[mod_state];
92 }
93 
94 static const char * const dev_state_strings[] = {
95 	[SFP_DEV_DETACHED] = "detached",
96 	[SFP_DEV_DOWN] = "down",
97 	[SFP_DEV_UP] = "up",
98 };
99 
100 static const char *dev_state_to_str(unsigned short dev_state)
101 {
102 	if (dev_state >= ARRAY_SIZE(dev_state_strings))
103 		return "Unknown device state";
104 	return dev_state_strings[dev_state];
105 }
106 
107 static const char * const event_strings[] = {
108 	[SFP_E_INSERT] = "insert",
109 	[SFP_E_REMOVE] = "remove",
110 	[SFP_E_DEV_ATTACH] = "dev_attach",
111 	[SFP_E_DEV_DETACH] = "dev_detach",
112 	[SFP_E_DEV_DOWN] = "dev_down",
113 	[SFP_E_DEV_UP] = "dev_up",
114 	[SFP_E_TX_FAULT] = "tx_fault",
115 	[SFP_E_TX_CLEAR] = "tx_clear",
116 	[SFP_E_LOS_HIGH] = "los_high",
117 	[SFP_E_LOS_LOW] = "los_low",
118 	[SFP_E_TIMEOUT] = "timeout",
119 };
120 
121 static const char *event_to_str(unsigned short event)
122 {
123 	if (event >= ARRAY_SIZE(event_strings))
124 		return "Unknown event";
125 	return event_strings[event];
126 }
127 
128 static const char * const sm_state_strings[] = {
129 	[SFP_S_DOWN] = "down",
130 	[SFP_S_FAIL] = "fail",
131 	[SFP_S_WAIT] = "wait",
132 	[SFP_S_INIT] = "init",
133 	[SFP_S_INIT_PHY] = "init_phy",
134 	[SFP_S_INIT_TX_FAULT] = "init_tx_fault",
135 	[SFP_S_WAIT_LOS] = "wait_los",
136 	[SFP_S_LINK_UP] = "link_up",
137 	[SFP_S_TX_FAULT] = "tx_fault",
138 	[SFP_S_REINIT] = "reinit",
139 	[SFP_S_TX_DISABLE] = "tx_disable",
140 };
141 
142 static const char *sm_state_to_str(unsigned short sm_state)
143 {
144 	if (sm_state >= ARRAY_SIZE(sm_state_strings))
145 		return "Unknown state";
146 	return sm_state_strings[sm_state];
147 }
148 
149 static const char *gpio_names[] = {
150 	"mod-def0",
151 	"los",
152 	"tx-fault",
153 	"tx-disable",
154 	"rate-select0",
155 	"rate-select1",
156 };
157 
158 static const enum gpiod_flags gpio_flags[] = {
159 	GPIOD_IN,
160 	GPIOD_IN,
161 	GPIOD_IN,
162 	GPIOD_ASIS,
163 	GPIOD_ASIS,
164 	GPIOD_ASIS,
165 };
166 
167 /* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
168  * non-cooled module to initialise its laser safety circuitry. We wait
169  * an initial T_WAIT period before we check the tx fault to give any PHY
170  * on board (for a copper SFP) time to initialise.
171  */
172 #define T_WAIT			msecs_to_jiffies(50)
173 #define T_START_UP		msecs_to_jiffies(300)
174 #define T_START_UP_BAD_GPON	msecs_to_jiffies(60000)
175 
176 /* t_reset is the time required to assert the TX_DISABLE signal to reset
177  * an indicated TX_FAULT.
178  */
179 #define T_RESET_US		10
180 #define T_FAULT_RECOVER		msecs_to_jiffies(1000)
181 
182 /* N_FAULT_INIT is the number of recovery attempts at module initialisation
183  * time. If the TX_FAULT signal is not deasserted after this number of
184  * attempts at clearing it, we decide that the module is faulty.
185  * N_FAULT is the same but after the module has initialised.
186  */
187 #define N_FAULT_INIT		5
188 #define N_FAULT			5
189 
190 /* T_PHY_RETRY is the time interval between attempts to probe the PHY.
191  * R_PHY_RETRY is the number of attempts.
192  */
193 #define T_PHY_RETRY		msecs_to_jiffies(50)
194 #define R_PHY_RETRY		12
195 
196 /* SFP module presence detection is poor: the three MOD DEF signals are
197  * the same length on the PCB, which means it's possible for MOD DEF 0 to
198  * connect before the I2C bus on MOD DEF 1/2.
199  *
200  * The SFF-8472 specifies t_serial ("Time from power on until module is
201  * ready for data transmission over the two wire serial bus.") as 300ms.
202  */
203 #define T_SERIAL		msecs_to_jiffies(300)
204 #define T_HPOWER_LEVEL		msecs_to_jiffies(300)
205 #define T_PROBE_RETRY_INIT	msecs_to_jiffies(100)
206 #define R_PROBE_RETRY_INIT	10
207 #define T_PROBE_RETRY_SLOW	msecs_to_jiffies(5000)
208 #define R_PROBE_RETRY_SLOW	12
209 
210 /* SFP modules appear to always have their PHY configured for bus address
211  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
212  * RollBall SFPs access phy via SFP Enhanced Digital Diagnostic Interface
213  * via address 0x51 (mdio-i2c will use RollBall protocol on this address).
214  */
215 #define SFP_PHY_ADDR		22
216 #define SFP_PHY_ADDR_ROLLBALL	17
217 
218 /* SFP_EEPROM_BLOCK_SIZE is the size of data chunk to read the EEPROM
219  * at a time. Some SFP modules and also some Linux I2C drivers do not like
220  * reads longer than 16 bytes.
221  */
222 #define SFP_EEPROM_BLOCK_SIZE	16
223 
224 struct sff_data {
225 	unsigned int gpios;
226 	bool (*module_supported)(const struct sfp_eeprom_id *id);
227 };
228 
229 struct sfp {
230 	struct device *dev;
231 	struct i2c_adapter *i2c;
232 	struct mii_bus *i2c_mii;
233 	struct sfp_bus *sfp_bus;
234 	enum mdio_i2c_proto mdio_protocol;
235 	struct phy_device *mod_phy;
236 	const struct sff_data *type;
237 	size_t i2c_block_size;
238 	u32 max_power_mW;
239 
240 	unsigned int (*get_state)(struct sfp *);
241 	void (*set_state)(struct sfp *, unsigned int);
242 	int (*read)(struct sfp *, bool, u8, void *, size_t);
243 	int (*write)(struct sfp *, bool, u8, void *, size_t);
244 
245 	struct gpio_desc *gpio[GPIO_MAX];
246 	int gpio_irq[GPIO_MAX];
247 
248 	bool need_poll;
249 
250 	/* Access rules:
251 	 * state_hw_drive: st_mutex held
252 	 * state_hw_mask: st_mutex held
253 	 * state_soft_mask: st_mutex held
254 	 * state: st_mutex held unless reading input bits
255 	 */
256 	struct mutex st_mutex;			/* Protects state */
257 	unsigned int state_hw_drive;
258 	unsigned int state_hw_mask;
259 	unsigned int state_soft_mask;
260 	unsigned int state;
261 
262 	struct delayed_work poll;
263 	struct delayed_work timeout;
264 	struct mutex sm_mutex;			/* Protects state machine */
265 	unsigned char sm_mod_state;
266 	unsigned char sm_mod_tries_init;
267 	unsigned char sm_mod_tries;
268 	unsigned char sm_dev_state;
269 	unsigned short sm_state;
270 	unsigned char sm_fault_retries;
271 	unsigned char sm_phy_retries;
272 
273 	struct sfp_eeprom_id id;
274 	unsigned int module_power_mW;
275 	unsigned int module_t_start_up;
276 	unsigned int module_t_wait;
277 
278 	unsigned int rate_kbd;
279 	unsigned int rs_threshold_kbd;
280 	unsigned int rs_state_mask;
281 
282 	bool have_a2;
283 	bool tx_fault_ignore;
284 
285 	const struct sfp_quirk *quirk;
286 
287 #if IS_ENABLED(CONFIG_HWMON)
288 	struct sfp_diag diag;
289 	struct delayed_work hwmon_probe;
290 	unsigned int hwmon_tries;
291 	struct device *hwmon_dev;
292 	char *hwmon_name;
293 #endif
294 
295 #if IS_ENABLED(CONFIG_DEBUG_FS)
296 	struct dentry *debugfs_dir;
297 #endif
298 };
299 
300 static bool sff_module_supported(const struct sfp_eeprom_id *id)
301 {
302 	return id->base.phys_id == SFF8024_ID_SFF_8472 &&
303 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
304 }
305 
306 static const struct sff_data sff_data = {
307 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
308 	.module_supported = sff_module_supported,
309 };
310 
311 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
312 {
313 	if (id->base.phys_id == SFF8024_ID_SFP &&
314 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP)
315 		return true;
316 
317 	/* SFP GPON module Ubiquiti U-Fiber Instant has in its EEPROM stored
318 	 * phys id SFF instead of SFP. Therefore mark this module explicitly
319 	 * as supported based on vendor name and pn match.
320 	 */
321 	if (id->base.phys_id == SFF8024_ID_SFF_8472 &&
322 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP &&
323 	    !memcmp(id->base.vendor_name, "UBNT            ", 16) &&
324 	    !memcmp(id->base.vendor_pn, "UF-INSTANT      ", 16))
325 		return true;
326 
327 	return false;
328 }
329 
330 static const struct sff_data sfp_data = {
331 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
332 		 SFP_F_TX_DISABLE | SFP_F_RS0 | SFP_F_RS1,
333 	.module_supported = sfp_module_supported,
334 };
335 
336 static const struct of_device_id sfp_of_match[] = {
337 	{ .compatible = "sff,sff", .data = &sff_data, },
338 	{ .compatible = "sff,sfp", .data = &sfp_data, },
339 	{ },
340 };
341 MODULE_DEVICE_TABLE(of, sfp_of_match);
342 
343 static void sfp_fixup_long_startup(struct sfp *sfp)
344 {
345 	sfp->module_t_start_up = T_START_UP_BAD_GPON;
346 }
347 
348 static void sfp_fixup_ignore_tx_fault(struct sfp *sfp)
349 {
350 	sfp->tx_fault_ignore = true;
351 }
352 
353 // For 10GBASE-T short-reach modules
354 static void sfp_fixup_10gbaset_30m(struct sfp *sfp)
355 {
356 	sfp->id.base.connector = SFF8024_CONNECTOR_RJ45;
357 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SR;
358 }
359 
360 static void sfp_fixup_rollball_proto(struct sfp *sfp, unsigned int secs)
361 {
362 	sfp->mdio_protocol = MDIO_I2C_ROLLBALL;
363 	sfp->module_t_wait = msecs_to_jiffies(secs * 1000);
364 }
365 
366 static void sfp_fixup_fs_10gt(struct sfp *sfp)
367 {
368 	sfp_fixup_10gbaset_30m(sfp);
369 
370 	// These SFPs need 4 seconds before the PHY can be accessed
371 	sfp_fixup_rollball_proto(sfp, 4);
372 }
373 
374 static void sfp_fixup_halny_gsfp(struct sfp *sfp)
375 {
376 	/* Ignore the TX_FAULT and LOS signals on this module.
377 	 * these are possibly used for other purposes on this
378 	 * module, e.g. a serial port.
379 	 */
380 	sfp->state_hw_mask &= ~(SFP_F_TX_FAULT | SFP_F_LOS);
381 }
382 
383 static void sfp_fixup_rollball(struct sfp *sfp)
384 {
385 	// Rollball SFPs need 25 seconds before the PHY can be accessed
386 	sfp_fixup_rollball_proto(sfp, 25);
387 }
388 
389 static void sfp_fixup_rollball_cc(struct sfp *sfp)
390 {
391 	sfp_fixup_rollball(sfp);
392 
393 	/* Some RollBall SFPs may have wrong (zero) extended compliance code
394 	 * burned in EEPROM. For PHY probing we need the correct one.
395 	 */
396 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SFI;
397 }
398 
399 static void sfp_quirk_2500basex(const struct sfp_eeprom_id *id,
400 				unsigned long *modes,
401 				unsigned long *interfaces)
402 {
403 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseX_Full_BIT, modes);
404 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
405 }
406 
407 static void sfp_quirk_disable_autoneg(const struct sfp_eeprom_id *id,
408 				      unsigned long *modes,
409 				      unsigned long *interfaces)
410 {
411 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, modes);
412 }
413 
414 static void sfp_quirk_oem_2_5g(const struct sfp_eeprom_id *id,
415 			       unsigned long *modes,
416 			       unsigned long *interfaces)
417 {
418 	/* Copper 2.5G SFP */
419 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT, modes);
420 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
421 	sfp_quirk_disable_autoneg(id, modes, interfaces);
422 }
423 
424 static void sfp_quirk_ubnt_uf_instant(const struct sfp_eeprom_id *id,
425 				      unsigned long *modes,
426 				      unsigned long *interfaces)
427 {
428 	/* Ubiquiti U-Fiber Instant module claims that support all transceiver
429 	 * types including 10G Ethernet which is not truth. So clear all claimed
430 	 * modes and set only one mode which module supports: 1000baseX_Full.
431 	 */
432 	linkmode_zero(modes);
433 	linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT, modes);
434 }
435 
436 #define SFP_QUIRK(_v, _p, _m, _f) \
437 	{ .vendor = _v, .part = _p, .modes = _m, .fixup = _f, }
438 #define SFP_QUIRK_M(_v, _p, _m) SFP_QUIRK(_v, _p, _m, NULL)
439 #define SFP_QUIRK_F(_v, _p, _f) SFP_QUIRK(_v, _p, NULL, _f)
440 
441 static const struct sfp_quirk sfp_quirks[] = {
442 	// Alcatel Lucent G-010S-P can operate at 2500base-X, but incorrectly
443 	// report 2500MBd NRZ in their EEPROM
444 	SFP_QUIRK_M("ALCATELLUCENT", "G010SP", sfp_quirk_2500basex),
445 
446 	// Alcatel Lucent G-010S-A can operate at 2500base-X, but report 3.2GBd
447 	// NRZ in their EEPROM
448 	SFP_QUIRK("ALCATELLUCENT", "3FE46541AA", sfp_quirk_2500basex,
449 		  sfp_fixup_long_startup),
450 
451 	// Fiberstore SFP-10G-T doesn't identify as copper, and uses the
452 	// Rollball protocol to talk to the PHY.
453 	SFP_QUIRK_F("FS", "SFP-10G-T", sfp_fixup_fs_10gt),
454 
455 	SFP_QUIRK_F("HALNy", "HL-GSFP", sfp_fixup_halny_gsfp),
456 
457 	// HG MXPD-483II-F 2.5G supports 2500Base-X, but incorrectly reports
458 	// 2600MBd in their EERPOM
459 	SFP_QUIRK_M("HG GENUINE", "MXPD-483II", sfp_quirk_2500basex),
460 
461 	// Huawei MA5671A can operate at 2500base-X, but report 1.2GBd NRZ in
462 	// their EEPROM
463 	SFP_QUIRK("HUAWEI", "MA5671A", sfp_quirk_2500basex,
464 		  sfp_fixup_ignore_tx_fault),
465 
466 	// Lantech 8330-262D-E can operate at 2500base-X, but incorrectly report
467 	// 2500MBd NRZ in their EEPROM
468 	SFP_QUIRK_M("Lantech", "8330-262D-E", sfp_quirk_2500basex),
469 
470 	SFP_QUIRK_M("UBNT", "UF-INSTANT", sfp_quirk_ubnt_uf_instant),
471 
472 	// Walsun HXSX-ATRC-1 doesn't identify as copper, and uses the
473 	// Rollball protocol to talk to the PHY.
474 	SFP_QUIRK_F("Walsun", "HXSX-ATRC-1", sfp_fixup_fs_10gt),
475 
476 	SFP_QUIRK_F("OEM", "SFP-10G-T", sfp_fixup_rollball_cc),
477 	SFP_QUIRK_M("OEM", "SFP-2.5G-T", sfp_quirk_oem_2_5g),
478 	SFP_QUIRK_F("OEM", "RTSFP-10", sfp_fixup_rollball_cc),
479 	SFP_QUIRK_F("OEM", "RTSFP-10G", sfp_fixup_rollball_cc),
480 	SFP_QUIRK_F("Turris", "RTSFP-10", sfp_fixup_rollball),
481 	SFP_QUIRK_F("Turris", "RTSFP-10G", sfp_fixup_rollball),
482 };
483 
484 static size_t sfp_strlen(const char *str, size_t maxlen)
485 {
486 	size_t size, i;
487 
488 	/* Trailing characters should be filled with space chars, but
489 	 * some manufacturers can't read SFF-8472 and use NUL.
490 	 */
491 	for (i = 0, size = 0; i < maxlen; i++)
492 		if (str[i] != ' ' && str[i] != '\0')
493 			size = i + 1;
494 
495 	return size;
496 }
497 
498 static bool sfp_match(const char *qs, const char *str, size_t len)
499 {
500 	if (!qs)
501 		return true;
502 	if (strlen(qs) != len)
503 		return false;
504 	return !strncmp(qs, str, len);
505 }
506 
507 static const struct sfp_quirk *sfp_lookup_quirk(const struct sfp_eeprom_id *id)
508 {
509 	const struct sfp_quirk *q;
510 	unsigned int i;
511 	size_t vs, ps;
512 
513 	vs = sfp_strlen(id->base.vendor_name, ARRAY_SIZE(id->base.vendor_name));
514 	ps = sfp_strlen(id->base.vendor_pn, ARRAY_SIZE(id->base.vendor_pn));
515 
516 	for (i = 0, q = sfp_quirks; i < ARRAY_SIZE(sfp_quirks); i++, q++)
517 		if (sfp_match(q->vendor, id->base.vendor_name, vs) &&
518 		    sfp_match(q->part, id->base.vendor_pn, ps))
519 			return q;
520 
521 	return NULL;
522 }
523 
524 static unsigned long poll_jiffies;
525 
526 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
527 {
528 	unsigned int i, state, v;
529 
530 	for (i = state = 0; i < GPIO_MAX; i++) {
531 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
532 			continue;
533 
534 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
535 		if (v)
536 			state |= BIT(i);
537 	}
538 
539 	return state;
540 }
541 
542 static unsigned int sff_gpio_get_state(struct sfp *sfp)
543 {
544 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
545 }
546 
547 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
548 {
549 	unsigned int drive;
550 
551 	if (state & SFP_F_PRESENT)
552 		/* If the module is present, drive the requested signals */
553 		drive = sfp->state_hw_drive;
554 	else
555 		/* Otherwise, let them float to the pull-ups */
556 		drive = 0;
557 
558 	if (sfp->gpio[GPIO_TX_DISABLE]) {
559 		if (drive & SFP_F_TX_DISABLE)
560 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
561 					       state & SFP_F_TX_DISABLE);
562 		else
563 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
564 	}
565 
566 	if (sfp->gpio[GPIO_RS0]) {
567 		if (drive & SFP_F_RS0)
568 			gpiod_direction_output(sfp->gpio[GPIO_RS0],
569 					       state & SFP_F_RS0);
570 		else
571 			gpiod_direction_input(sfp->gpio[GPIO_RS0]);
572 	}
573 
574 	if (sfp->gpio[GPIO_RS1]) {
575 		if (drive & SFP_F_RS1)
576 			gpiod_direction_output(sfp->gpio[GPIO_RS1],
577 					       state & SFP_F_RS1);
578 		else
579 			gpiod_direction_input(sfp->gpio[GPIO_RS1]);
580 	}
581 }
582 
583 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
584 			size_t len)
585 {
586 	struct i2c_msg msgs[2];
587 	u8 bus_addr = a2 ? 0x51 : 0x50;
588 	size_t block_size = sfp->i2c_block_size;
589 	size_t this_len;
590 	int ret;
591 
592 	msgs[0].addr = bus_addr;
593 	msgs[0].flags = 0;
594 	msgs[0].len = 1;
595 	msgs[0].buf = &dev_addr;
596 	msgs[1].addr = bus_addr;
597 	msgs[1].flags = I2C_M_RD;
598 	msgs[1].len = len;
599 	msgs[1].buf = buf;
600 
601 	while (len) {
602 		this_len = len;
603 		if (this_len > block_size)
604 			this_len = block_size;
605 
606 		msgs[1].len = this_len;
607 
608 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
609 		if (ret < 0)
610 			return ret;
611 
612 		if (ret != ARRAY_SIZE(msgs))
613 			break;
614 
615 		msgs[1].buf += this_len;
616 		dev_addr += this_len;
617 		len -= this_len;
618 	}
619 
620 	return msgs[1].buf - (u8 *)buf;
621 }
622 
623 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
624 	size_t len)
625 {
626 	struct i2c_msg msgs[1];
627 	u8 bus_addr = a2 ? 0x51 : 0x50;
628 	int ret;
629 
630 	msgs[0].addr = bus_addr;
631 	msgs[0].flags = 0;
632 	msgs[0].len = 1 + len;
633 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
634 	if (!msgs[0].buf)
635 		return -ENOMEM;
636 
637 	msgs[0].buf[0] = dev_addr;
638 	memcpy(&msgs[0].buf[1], buf, len);
639 
640 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
641 
642 	kfree(msgs[0].buf);
643 
644 	if (ret < 0)
645 		return ret;
646 
647 	return ret == ARRAY_SIZE(msgs) ? len : 0;
648 }
649 
650 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
651 {
652 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
653 		return -EINVAL;
654 
655 	sfp->i2c = i2c;
656 	sfp->read = sfp_i2c_read;
657 	sfp->write = sfp_i2c_write;
658 
659 	return 0;
660 }
661 
662 static int sfp_i2c_mdiobus_create(struct sfp *sfp)
663 {
664 	struct mii_bus *i2c_mii;
665 	int ret;
666 
667 	i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, sfp->mdio_protocol);
668 	if (IS_ERR(i2c_mii))
669 		return PTR_ERR(i2c_mii);
670 
671 	i2c_mii->name = "SFP I2C Bus";
672 	i2c_mii->phy_mask = ~0;
673 
674 	ret = mdiobus_register(i2c_mii);
675 	if (ret < 0) {
676 		mdiobus_free(i2c_mii);
677 		return ret;
678 	}
679 
680 	sfp->i2c_mii = i2c_mii;
681 
682 	return 0;
683 }
684 
685 static void sfp_i2c_mdiobus_destroy(struct sfp *sfp)
686 {
687 	mdiobus_unregister(sfp->i2c_mii);
688 	sfp->i2c_mii = NULL;
689 }
690 
691 /* Interface */
692 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
693 {
694 	return sfp->read(sfp, a2, addr, buf, len);
695 }
696 
697 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
698 {
699 	return sfp->write(sfp, a2, addr, buf, len);
700 }
701 
702 static int sfp_modify_u8(struct sfp *sfp, bool a2, u8 addr, u8 mask, u8 val)
703 {
704 	int ret;
705 	u8 old, v;
706 
707 	ret = sfp_read(sfp, a2, addr, &old, sizeof(old));
708 	if (ret != sizeof(old))
709 		return ret;
710 
711 	v = (old & ~mask) | (val & mask);
712 	if (v == old)
713 		return sizeof(v);
714 
715 	return sfp_write(sfp, a2, addr, &v, sizeof(v));
716 }
717 
718 static unsigned int sfp_soft_get_state(struct sfp *sfp)
719 {
720 	unsigned int state = 0;
721 	u8 status;
722 	int ret;
723 
724 	ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
725 	if (ret == sizeof(status)) {
726 		if (status & SFP_STATUS_RX_LOS)
727 			state |= SFP_F_LOS;
728 		if (status & SFP_STATUS_TX_FAULT)
729 			state |= SFP_F_TX_FAULT;
730 	} else {
731 		dev_err_ratelimited(sfp->dev,
732 				    "failed to read SFP soft status: %pe\n",
733 				    ERR_PTR(ret));
734 		/* Preserve the current state */
735 		state = sfp->state;
736 	}
737 
738 	return state & sfp->state_soft_mask;
739 }
740 
741 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state,
742 			       unsigned int soft)
743 {
744 	u8 mask = 0;
745 	u8 val = 0;
746 
747 	if (soft & SFP_F_TX_DISABLE)
748 		mask |= SFP_STATUS_TX_DISABLE_FORCE;
749 	if (state & SFP_F_TX_DISABLE)
750 		val |= SFP_STATUS_TX_DISABLE_FORCE;
751 
752 	if (soft & SFP_F_RS0)
753 		mask |= SFP_STATUS_RS0_SELECT;
754 	if (state & SFP_F_RS0)
755 		val |= SFP_STATUS_RS0_SELECT;
756 
757 	if (mask)
758 		sfp_modify_u8(sfp, true, SFP_STATUS, mask, val);
759 
760 	val = mask = 0;
761 	if (soft & SFP_F_RS1)
762 		mask |= SFP_EXT_STATUS_RS1_SELECT;
763 	if (state & SFP_F_RS1)
764 		val |= SFP_EXT_STATUS_RS1_SELECT;
765 
766 	if (mask)
767 		sfp_modify_u8(sfp, true, SFP_EXT_STATUS, mask, val);
768 }
769 
770 static void sfp_soft_start_poll(struct sfp *sfp)
771 {
772 	const struct sfp_eeprom_id *id = &sfp->id;
773 	unsigned int mask = 0;
774 
775 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE)
776 		mask |= SFP_F_TX_DISABLE;
777 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT)
778 		mask |= SFP_F_TX_FAULT;
779 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS)
780 		mask |= SFP_F_LOS;
781 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RATE_SELECT)
782 		mask |= sfp->rs_state_mask;
783 
784 	mutex_lock(&sfp->st_mutex);
785 	// Poll the soft state for hardware pins we want to ignore
786 	sfp->state_soft_mask = ~sfp->state_hw_mask & mask;
787 
788 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
789 	    !sfp->need_poll)
790 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
791 	mutex_unlock(&sfp->st_mutex);
792 }
793 
794 static void sfp_soft_stop_poll(struct sfp *sfp)
795 {
796 	mutex_lock(&sfp->st_mutex);
797 	sfp->state_soft_mask = 0;
798 	mutex_unlock(&sfp->st_mutex);
799 }
800 
801 /* sfp_get_state() - must be called with st_mutex held, or in the
802  * initialisation path.
803  */
804 static unsigned int sfp_get_state(struct sfp *sfp)
805 {
806 	unsigned int soft = sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT);
807 	unsigned int state;
808 
809 	state = sfp->get_state(sfp) & sfp->state_hw_mask;
810 	if (state & SFP_F_PRESENT && soft)
811 		state |= sfp_soft_get_state(sfp);
812 
813 	return state;
814 }
815 
816 /* sfp_set_state() - must be called with st_mutex held, or in the
817  * initialisation path.
818  */
819 static void sfp_set_state(struct sfp *sfp, unsigned int state)
820 {
821 	unsigned int soft;
822 
823 	sfp->set_state(sfp, state);
824 
825 	soft = sfp->state_soft_mask & SFP_F_OUTPUTS;
826 	if (state & SFP_F_PRESENT && soft)
827 		sfp_soft_set_state(sfp, state, soft);
828 }
829 
830 static void sfp_mod_state(struct sfp *sfp, unsigned int mask, unsigned int set)
831 {
832 	mutex_lock(&sfp->st_mutex);
833 	sfp->state = (sfp->state & ~mask) | set;
834 	sfp_set_state(sfp, sfp->state);
835 	mutex_unlock(&sfp->st_mutex);
836 }
837 
838 static unsigned int sfp_check(void *buf, size_t len)
839 {
840 	u8 *p, check;
841 
842 	for (p = buf, check = 0; len; p++, len--)
843 		check += *p;
844 
845 	return check;
846 }
847 
848 /* hwmon */
849 #if IS_ENABLED(CONFIG_HWMON)
850 static umode_t sfp_hwmon_is_visible(const void *data,
851 				    enum hwmon_sensor_types type,
852 				    u32 attr, int channel)
853 {
854 	const struct sfp *sfp = data;
855 
856 	switch (type) {
857 	case hwmon_temp:
858 		switch (attr) {
859 		case hwmon_temp_min_alarm:
860 		case hwmon_temp_max_alarm:
861 		case hwmon_temp_lcrit_alarm:
862 		case hwmon_temp_crit_alarm:
863 		case hwmon_temp_min:
864 		case hwmon_temp_max:
865 		case hwmon_temp_lcrit:
866 		case hwmon_temp_crit:
867 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
868 				return 0;
869 			fallthrough;
870 		case hwmon_temp_input:
871 		case hwmon_temp_label:
872 			return 0444;
873 		default:
874 			return 0;
875 		}
876 	case hwmon_in:
877 		switch (attr) {
878 		case hwmon_in_min_alarm:
879 		case hwmon_in_max_alarm:
880 		case hwmon_in_lcrit_alarm:
881 		case hwmon_in_crit_alarm:
882 		case hwmon_in_min:
883 		case hwmon_in_max:
884 		case hwmon_in_lcrit:
885 		case hwmon_in_crit:
886 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
887 				return 0;
888 			fallthrough;
889 		case hwmon_in_input:
890 		case hwmon_in_label:
891 			return 0444;
892 		default:
893 			return 0;
894 		}
895 	case hwmon_curr:
896 		switch (attr) {
897 		case hwmon_curr_min_alarm:
898 		case hwmon_curr_max_alarm:
899 		case hwmon_curr_lcrit_alarm:
900 		case hwmon_curr_crit_alarm:
901 		case hwmon_curr_min:
902 		case hwmon_curr_max:
903 		case hwmon_curr_lcrit:
904 		case hwmon_curr_crit:
905 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
906 				return 0;
907 			fallthrough;
908 		case hwmon_curr_input:
909 		case hwmon_curr_label:
910 			return 0444;
911 		default:
912 			return 0;
913 		}
914 	case hwmon_power:
915 		/* External calibration of receive power requires
916 		 * floating point arithmetic. Doing that in the kernel
917 		 * is not easy, so just skip it. If the module does
918 		 * not require external calibration, we can however
919 		 * show receiver power, since FP is then not needed.
920 		 */
921 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
922 		    channel == 1)
923 			return 0;
924 		switch (attr) {
925 		case hwmon_power_min_alarm:
926 		case hwmon_power_max_alarm:
927 		case hwmon_power_lcrit_alarm:
928 		case hwmon_power_crit_alarm:
929 		case hwmon_power_min:
930 		case hwmon_power_max:
931 		case hwmon_power_lcrit:
932 		case hwmon_power_crit:
933 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
934 				return 0;
935 			fallthrough;
936 		case hwmon_power_input:
937 		case hwmon_power_label:
938 			return 0444;
939 		default:
940 			return 0;
941 		}
942 	default:
943 		return 0;
944 	}
945 }
946 
947 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
948 {
949 	__be16 val;
950 	int err;
951 
952 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
953 	if (err < 0)
954 		return err;
955 
956 	*value = be16_to_cpu(val);
957 
958 	return 0;
959 }
960 
961 static void sfp_hwmon_to_rx_power(long *value)
962 {
963 	*value = DIV_ROUND_CLOSEST(*value, 10);
964 }
965 
966 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
967 				long *value)
968 {
969 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
970 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
971 }
972 
973 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
974 {
975 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
976 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
977 
978 	if (*value >= 0x8000)
979 		*value -= 0x10000;
980 
981 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
982 }
983 
984 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
985 {
986 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
987 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
988 
989 	*value = DIV_ROUND_CLOSEST(*value, 10);
990 }
991 
992 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
993 {
994 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
995 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
996 
997 	*value = DIV_ROUND_CLOSEST(*value, 500);
998 }
999 
1000 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
1001 {
1002 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
1003 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
1004 
1005 	*value = DIV_ROUND_CLOSEST(*value, 10);
1006 }
1007 
1008 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
1009 {
1010 	int err;
1011 
1012 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1013 	if (err < 0)
1014 		return err;
1015 
1016 	sfp_hwmon_calibrate_temp(sfp, value);
1017 
1018 	return 0;
1019 }
1020 
1021 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
1022 {
1023 	int err;
1024 
1025 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1026 	if (err < 0)
1027 		return err;
1028 
1029 	sfp_hwmon_calibrate_vcc(sfp, value);
1030 
1031 	return 0;
1032 }
1033 
1034 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
1035 {
1036 	int err;
1037 
1038 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1039 	if (err < 0)
1040 		return err;
1041 
1042 	sfp_hwmon_calibrate_bias(sfp, value);
1043 
1044 	return 0;
1045 }
1046 
1047 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
1048 {
1049 	int err;
1050 
1051 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1052 	if (err < 0)
1053 		return err;
1054 
1055 	sfp_hwmon_calibrate_tx_power(sfp, value);
1056 
1057 	return 0;
1058 }
1059 
1060 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
1061 {
1062 	int err;
1063 
1064 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1065 	if (err < 0)
1066 		return err;
1067 
1068 	sfp_hwmon_to_rx_power(value);
1069 
1070 	return 0;
1071 }
1072 
1073 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
1074 {
1075 	u8 status;
1076 	int err;
1077 
1078 	switch (attr) {
1079 	case hwmon_temp_input:
1080 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
1081 
1082 	case hwmon_temp_lcrit:
1083 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
1084 		sfp_hwmon_calibrate_temp(sfp, value);
1085 		return 0;
1086 
1087 	case hwmon_temp_min:
1088 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
1089 		sfp_hwmon_calibrate_temp(sfp, value);
1090 		return 0;
1091 	case hwmon_temp_max:
1092 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
1093 		sfp_hwmon_calibrate_temp(sfp, value);
1094 		return 0;
1095 
1096 	case hwmon_temp_crit:
1097 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
1098 		sfp_hwmon_calibrate_temp(sfp, value);
1099 		return 0;
1100 
1101 	case hwmon_temp_lcrit_alarm:
1102 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1103 		if (err < 0)
1104 			return err;
1105 
1106 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
1107 		return 0;
1108 
1109 	case hwmon_temp_min_alarm:
1110 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1111 		if (err < 0)
1112 			return err;
1113 
1114 		*value = !!(status & SFP_WARN0_TEMP_LOW);
1115 		return 0;
1116 
1117 	case hwmon_temp_max_alarm:
1118 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1119 		if (err < 0)
1120 			return err;
1121 
1122 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
1123 		return 0;
1124 
1125 	case hwmon_temp_crit_alarm:
1126 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1127 		if (err < 0)
1128 			return err;
1129 
1130 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
1131 		return 0;
1132 	default:
1133 		return -EOPNOTSUPP;
1134 	}
1135 
1136 	return -EOPNOTSUPP;
1137 }
1138 
1139 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
1140 {
1141 	u8 status;
1142 	int err;
1143 
1144 	switch (attr) {
1145 	case hwmon_in_input:
1146 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
1147 
1148 	case hwmon_in_lcrit:
1149 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
1150 		sfp_hwmon_calibrate_vcc(sfp, value);
1151 		return 0;
1152 
1153 	case hwmon_in_min:
1154 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
1155 		sfp_hwmon_calibrate_vcc(sfp, value);
1156 		return 0;
1157 
1158 	case hwmon_in_max:
1159 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
1160 		sfp_hwmon_calibrate_vcc(sfp, value);
1161 		return 0;
1162 
1163 	case hwmon_in_crit:
1164 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
1165 		sfp_hwmon_calibrate_vcc(sfp, value);
1166 		return 0;
1167 
1168 	case hwmon_in_lcrit_alarm:
1169 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1170 		if (err < 0)
1171 			return err;
1172 
1173 		*value = !!(status & SFP_ALARM0_VCC_LOW);
1174 		return 0;
1175 
1176 	case hwmon_in_min_alarm:
1177 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1178 		if (err < 0)
1179 			return err;
1180 
1181 		*value = !!(status & SFP_WARN0_VCC_LOW);
1182 		return 0;
1183 
1184 	case hwmon_in_max_alarm:
1185 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1186 		if (err < 0)
1187 			return err;
1188 
1189 		*value = !!(status & SFP_WARN0_VCC_HIGH);
1190 		return 0;
1191 
1192 	case hwmon_in_crit_alarm:
1193 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1194 		if (err < 0)
1195 			return err;
1196 
1197 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
1198 		return 0;
1199 	default:
1200 		return -EOPNOTSUPP;
1201 	}
1202 
1203 	return -EOPNOTSUPP;
1204 }
1205 
1206 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
1207 {
1208 	u8 status;
1209 	int err;
1210 
1211 	switch (attr) {
1212 	case hwmon_curr_input:
1213 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
1214 
1215 	case hwmon_curr_lcrit:
1216 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
1217 		sfp_hwmon_calibrate_bias(sfp, value);
1218 		return 0;
1219 
1220 	case hwmon_curr_min:
1221 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
1222 		sfp_hwmon_calibrate_bias(sfp, value);
1223 		return 0;
1224 
1225 	case hwmon_curr_max:
1226 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
1227 		sfp_hwmon_calibrate_bias(sfp, value);
1228 		return 0;
1229 
1230 	case hwmon_curr_crit:
1231 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
1232 		sfp_hwmon_calibrate_bias(sfp, value);
1233 		return 0;
1234 
1235 	case hwmon_curr_lcrit_alarm:
1236 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1237 		if (err < 0)
1238 			return err;
1239 
1240 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
1241 		return 0;
1242 
1243 	case hwmon_curr_min_alarm:
1244 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1245 		if (err < 0)
1246 			return err;
1247 
1248 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
1249 		return 0;
1250 
1251 	case hwmon_curr_max_alarm:
1252 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1253 		if (err < 0)
1254 			return err;
1255 
1256 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
1257 		return 0;
1258 
1259 	case hwmon_curr_crit_alarm:
1260 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1261 		if (err < 0)
1262 			return err;
1263 
1264 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
1265 		return 0;
1266 	default:
1267 		return -EOPNOTSUPP;
1268 	}
1269 
1270 	return -EOPNOTSUPP;
1271 }
1272 
1273 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
1274 {
1275 	u8 status;
1276 	int err;
1277 
1278 	switch (attr) {
1279 	case hwmon_power_input:
1280 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
1281 
1282 	case hwmon_power_lcrit:
1283 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
1284 		sfp_hwmon_calibrate_tx_power(sfp, value);
1285 		return 0;
1286 
1287 	case hwmon_power_min:
1288 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
1289 		sfp_hwmon_calibrate_tx_power(sfp, value);
1290 		return 0;
1291 
1292 	case hwmon_power_max:
1293 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
1294 		sfp_hwmon_calibrate_tx_power(sfp, value);
1295 		return 0;
1296 
1297 	case hwmon_power_crit:
1298 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
1299 		sfp_hwmon_calibrate_tx_power(sfp, value);
1300 		return 0;
1301 
1302 	case hwmon_power_lcrit_alarm:
1303 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1304 		if (err < 0)
1305 			return err;
1306 
1307 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
1308 		return 0;
1309 
1310 	case hwmon_power_min_alarm:
1311 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1312 		if (err < 0)
1313 			return err;
1314 
1315 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
1316 		return 0;
1317 
1318 	case hwmon_power_max_alarm:
1319 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1320 		if (err < 0)
1321 			return err;
1322 
1323 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1324 		return 0;
1325 
1326 	case hwmon_power_crit_alarm:
1327 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1328 		if (err < 0)
1329 			return err;
1330 
1331 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1332 		return 0;
1333 	default:
1334 		return -EOPNOTSUPP;
1335 	}
1336 
1337 	return -EOPNOTSUPP;
1338 }
1339 
1340 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1341 {
1342 	u8 status;
1343 	int err;
1344 
1345 	switch (attr) {
1346 	case hwmon_power_input:
1347 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1348 
1349 	case hwmon_power_lcrit:
1350 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1351 		sfp_hwmon_to_rx_power(value);
1352 		return 0;
1353 
1354 	case hwmon_power_min:
1355 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1356 		sfp_hwmon_to_rx_power(value);
1357 		return 0;
1358 
1359 	case hwmon_power_max:
1360 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1361 		sfp_hwmon_to_rx_power(value);
1362 		return 0;
1363 
1364 	case hwmon_power_crit:
1365 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1366 		sfp_hwmon_to_rx_power(value);
1367 		return 0;
1368 
1369 	case hwmon_power_lcrit_alarm:
1370 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1371 		if (err < 0)
1372 			return err;
1373 
1374 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1375 		return 0;
1376 
1377 	case hwmon_power_min_alarm:
1378 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1379 		if (err < 0)
1380 			return err;
1381 
1382 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1383 		return 0;
1384 
1385 	case hwmon_power_max_alarm:
1386 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1387 		if (err < 0)
1388 			return err;
1389 
1390 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1391 		return 0;
1392 
1393 	case hwmon_power_crit_alarm:
1394 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1395 		if (err < 0)
1396 			return err;
1397 
1398 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1399 		return 0;
1400 	default:
1401 		return -EOPNOTSUPP;
1402 	}
1403 
1404 	return -EOPNOTSUPP;
1405 }
1406 
1407 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1408 			  u32 attr, int channel, long *value)
1409 {
1410 	struct sfp *sfp = dev_get_drvdata(dev);
1411 
1412 	switch (type) {
1413 	case hwmon_temp:
1414 		return sfp_hwmon_temp(sfp, attr, value);
1415 	case hwmon_in:
1416 		return sfp_hwmon_vcc(sfp, attr, value);
1417 	case hwmon_curr:
1418 		return sfp_hwmon_bias(sfp, attr, value);
1419 	case hwmon_power:
1420 		switch (channel) {
1421 		case 0:
1422 			return sfp_hwmon_tx_power(sfp, attr, value);
1423 		case 1:
1424 			return sfp_hwmon_rx_power(sfp, attr, value);
1425 		default:
1426 			return -EOPNOTSUPP;
1427 		}
1428 	default:
1429 		return -EOPNOTSUPP;
1430 	}
1431 }
1432 
1433 static const char *const sfp_hwmon_power_labels[] = {
1434 	"TX_power",
1435 	"RX_power",
1436 };
1437 
1438 static int sfp_hwmon_read_string(struct device *dev,
1439 				 enum hwmon_sensor_types type,
1440 				 u32 attr, int channel, const char **str)
1441 {
1442 	switch (type) {
1443 	case hwmon_curr:
1444 		switch (attr) {
1445 		case hwmon_curr_label:
1446 			*str = "bias";
1447 			return 0;
1448 		default:
1449 			return -EOPNOTSUPP;
1450 		}
1451 		break;
1452 	case hwmon_temp:
1453 		switch (attr) {
1454 		case hwmon_temp_label:
1455 			*str = "temperature";
1456 			return 0;
1457 		default:
1458 			return -EOPNOTSUPP;
1459 		}
1460 		break;
1461 	case hwmon_in:
1462 		switch (attr) {
1463 		case hwmon_in_label:
1464 			*str = "VCC";
1465 			return 0;
1466 		default:
1467 			return -EOPNOTSUPP;
1468 		}
1469 		break;
1470 	case hwmon_power:
1471 		switch (attr) {
1472 		case hwmon_power_label:
1473 			*str = sfp_hwmon_power_labels[channel];
1474 			return 0;
1475 		default:
1476 			return -EOPNOTSUPP;
1477 		}
1478 		break;
1479 	default:
1480 		return -EOPNOTSUPP;
1481 	}
1482 
1483 	return -EOPNOTSUPP;
1484 }
1485 
1486 static const struct hwmon_ops sfp_hwmon_ops = {
1487 	.is_visible = sfp_hwmon_is_visible,
1488 	.read = sfp_hwmon_read,
1489 	.read_string = sfp_hwmon_read_string,
1490 };
1491 
1492 static const struct hwmon_channel_info * const sfp_hwmon_info[] = {
1493 	HWMON_CHANNEL_INFO(chip,
1494 			   HWMON_C_REGISTER_TZ),
1495 	HWMON_CHANNEL_INFO(in,
1496 			   HWMON_I_INPUT |
1497 			   HWMON_I_MAX | HWMON_I_MIN |
1498 			   HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1499 			   HWMON_I_CRIT | HWMON_I_LCRIT |
1500 			   HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1501 			   HWMON_I_LABEL),
1502 	HWMON_CHANNEL_INFO(temp,
1503 			   HWMON_T_INPUT |
1504 			   HWMON_T_MAX | HWMON_T_MIN |
1505 			   HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1506 			   HWMON_T_CRIT | HWMON_T_LCRIT |
1507 			   HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1508 			   HWMON_T_LABEL),
1509 	HWMON_CHANNEL_INFO(curr,
1510 			   HWMON_C_INPUT |
1511 			   HWMON_C_MAX | HWMON_C_MIN |
1512 			   HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1513 			   HWMON_C_CRIT | HWMON_C_LCRIT |
1514 			   HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1515 			   HWMON_C_LABEL),
1516 	HWMON_CHANNEL_INFO(power,
1517 			   /* Transmit power */
1518 			   HWMON_P_INPUT |
1519 			   HWMON_P_MAX | HWMON_P_MIN |
1520 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1521 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1522 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1523 			   HWMON_P_LABEL,
1524 			   /* Receive power */
1525 			   HWMON_P_INPUT |
1526 			   HWMON_P_MAX | HWMON_P_MIN |
1527 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1528 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1529 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1530 			   HWMON_P_LABEL),
1531 	NULL,
1532 };
1533 
1534 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1535 	.ops = &sfp_hwmon_ops,
1536 	.info = sfp_hwmon_info,
1537 };
1538 
1539 static void sfp_hwmon_probe(struct work_struct *work)
1540 {
1541 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1542 	int err;
1543 
1544 	/* hwmon interface needs to access 16bit registers in atomic way to
1545 	 * guarantee coherency of the diagnostic monitoring data. If it is not
1546 	 * possible to guarantee coherency because EEPROM is broken in such way
1547 	 * that does not support atomic 16bit read operation then we have to
1548 	 * skip registration of hwmon device.
1549 	 */
1550 	if (sfp->i2c_block_size < 2) {
1551 		dev_info(sfp->dev,
1552 			 "skipping hwmon device registration due to broken EEPROM\n");
1553 		dev_info(sfp->dev,
1554 			 "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
1555 		return;
1556 	}
1557 
1558 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1559 	if (err < 0) {
1560 		if (sfp->hwmon_tries--) {
1561 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1562 					 T_PROBE_RETRY_SLOW);
1563 		} else {
1564 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
1565 				 ERR_PTR(err));
1566 		}
1567 		return;
1568 	}
1569 
1570 	sfp->hwmon_name = hwmon_sanitize_name(dev_name(sfp->dev));
1571 	if (IS_ERR(sfp->hwmon_name)) {
1572 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1573 		return;
1574 	}
1575 
1576 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1577 							 sfp->hwmon_name, sfp,
1578 							 &sfp_hwmon_chip_info,
1579 							 NULL);
1580 	if (IS_ERR(sfp->hwmon_dev))
1581 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1582 			PTR_ERR(sfp->hwmon_dev));
1583 }
1584 
1585 static int sfp_hwmon_insert(struct sfp *sfp)
1586 {
1587 	if (sfp->have_a2 && sfp->id.ext.diagmon & SFP_DIAGMON_DDM) {
1588 		mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1589 		sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1590 	}
1591 
1592 	return 0;
1593 }
1594 
1595 static void sfp_hwmon_remove(struct sfp *sfp)
1596 {
1597 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1598 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1599 		hwmon_device_unregister(sfp->hwmon_dev);
1600 		sfp->hwmon_dev = NULL;
1601 		kfree(sfp->hwmon_name);
1602 	}
1603 }
1604 
1605 static int sfp_hwmon_init(struct sfp *sfp)
1606 {
1607 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1608 
1609 	return 0;
1610 }
1611 
1612 static void sfp_hwmon_exit(struct sfp *sfp)
1613 {
1614 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1615 }
1616 #else
1617 static int sfp_hwmon_insert(struct sfp *sfp)
1618 {
1619 	return 0;
1620 }
1621 
1622 static void sfp_hwmon_remove(struct sfp *sfp)
1623 {
1624 }
1625 
1626 static int sfp_hwmon_init(struct sfp *sfp)
1627 {
1628 	return 0;
1629 }
1630 
1631 static void sfp_hwmon_exit(struct sfp *sfp)
1632 {
1633 }
1634 #endif
1635 
1636 /* Helpers */
1637 static void sfp_module_tx_disable(struct sfp *sfp)
1638 {
1639 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1640 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1641 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, SFP_F_TX_DISABLE);
1642 }
1643 
1644 static void sfp_module_tx_enable(struct sfp *sfp)
1645 {
1646 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1647 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1648 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, 0);
1649 }
1650 
1651 #if IS_ENABLED(CONFIG_DEBUG_FS)
1652 static int sfp_debug_state_show(struct seq_file *s, void *data)
1653 {
1654 	struct sfp *sfp = s->private;
1655 
1656 	seq_printf(s, "Module state: %s\n",
1657 		   mod_state_to_str(sfp->sm_mod_state));
1658 	seq_printf(s, "Module probe attempts: %d %d\n",
1659 		   R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
1660 		   R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
1661 	seq_printf(s, "Device state: %s\n",
1662 		   dev_state_to_str(sfp->sm_dev_state));
1663 	seq_printf(s, "Main state: %s\n",
1664 		   sm_state_to_str(sfp->sm_state));
1665 	seq_printf(s, "Fault recovery remaining retries: %d\n",
1666 		   sfp->sm_fault_retries);
1667 	seq_printf(s, "PHY probe remaining retries: %d\n",
1668 		   sfp->sm_phy_retries);
1669 	seq_printf(s, "Signalling rate: %u kBd\n", sfp->rate_kbd);
1670 	seq_printf(s, "Rate select threshold: %u kBd\n",
1671 		   sfp->rs_threshold_kbd);
1672 	seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
1673 	seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
1674 	seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
1675 	seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
1676 	seq_printf(s, "rs0: %d\n", !!(sfp->state & SFP_F_RS0));
1677 	seq_printf(s, "rs1: %d\n", !!(sfp->state & SFP_F_RS1));
1678 	return 0;
1679 }
1680 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
1681 
1682 static void sfp_debugfs_init(struct sfp *sfp)
1683 {
1684 	sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
1685 
1686 	debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
1687 			    &sfp_debug_state_fops);
1688 }
1689 
1690 static void sfp_debugfs_exit(struct sfp *sfp)
1691 {
1692 	debugfs_remove_recursive(sfp->debugfs_dir);
1693 }
1694 #else
1695 static void sfp_debugfs_init(struct sfp *sfp)
1696 {
1697 }
1698 
1699 static void sfp_debugfs_exit(struct sfp *sfp)
1700 {
1701 }
1702 #endif
1703 
1704 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1705 {
1706 	unsigned int state;
1707 
1708 	mutex_lock(&sfp->st_mutex);
1709 	state = sfp->state;
1710 	if (!(state & SFP_F_TX_DISABLE)) {
1711 		sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1712 
1713 		udelay(T_RESET_US);
1714 
1715 		sfp_set_state(sfp, state);
1716 	}
1717 	mutex_unlock(&sfp->st_mutex);
1718 }
1719 
1720 /* SFP state machine */
1721 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1722 {
1723 	if (timeout)
1724 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1725 				 timeout);
1726 	else
1727 		cancel_delayed_work(&sfp->timeout);
1728 }
1729 
1730 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1731 			unsigned int timeout)
1732 {
1733 	sfp->sm_state = state;
1734 	sfp_sm_set_timer(sfp, timeout);
1735 }
1736 
1737 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1738 			    unsigned int timeout)
1739 {
1740 	sfp->sm_mod_state = state;
1741 	sfp_sm_set_timer(sfp, timeout);
1742 }
1743 
1744 static void sfp_sm_phy_detach(struct sfp *sfp)
1745 {
1746 	sfp_remove_phy(sfp->sfp_bus);
1747 	phy_device_remove(sfp->mod_phy);
1748 	phy_device_free(sfp->mod_phy);
1749 	sfp->mod_phy = NULL;
1750 }
1751 
1752 static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
1753 {
1754 	struct phy_device *phy;
1755 	int err;
1756 
1757 	phy = get_phy_device(sfp->i2c_mii, addr, is_c45);
1758 	if (phy == ERR_PTR(-ENODEV))
1759 		return PTR_ERR(phy);
1760 	if (IS_ERR(phy)) {
1761 		dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
1762 		return PTR_ERR(phy);
1763 	}
1764 
1765 	err = phy_device_register(phy);
1766 	if (err) {
1767 		phy_device_free(phy);
1768 		dev_err(sfp->dev, "phy_device_register failed: %pe\n",
1769 			ERR_PTR(err));
1770 		return err;
1771 	}
1772 
1773 	err = sfp_add_phy(sfp->sfp_bus, phy);
1774 	if (err) {
1775 		phy_device_remove(phy);
1776 		phy_device_free(phy);
1777 		dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
1778 		return err;
1779 	}
1780 
1781 	sfp->mod_phy = phy;
1782 
1783 	return 0;
1784 }
1785 
1786 static void sfp_sm_link_up(struct sfp *sfp)
1787 {
1788 	sfp_link_up(sfp->sfp_bus);
1789 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1790 }
1791 
1792 static void sfp_sm_link_down(struct sfp *sfp)
1793 {
1794 	sfp_link_down(sfp->sfp_bus);
1795 }
1796 
1797 static void sfp_sm_link_check_los(struct sfp *sfp)
1798 {
1799 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1800 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1801 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1802 	bool los = false;
1803 
1804 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1805 	 * are set, we assume that no LOS signal is available. If both are
1806 	 * set, we assume LOS is not implemented (and is meaningless.)
1807 	 */
1808 	if (los_options == los_inverted)
1809 		los = !(sfp->state & SFP_F_LOS);
1810 	else if (los_options == los_normal)
1811 		los = !!(sfp->state & SFP_F_LOS);
1812 
1813 	if (los)
1814 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1815 	else
1816 		sfp_sm_link_up(sfp);
1817 }
1818 
1819 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1820 {
1821 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1822 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1823 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1824 
1825 	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
1826 	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
1827 }
1828 
1829 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1830 {
1831 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1832 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1833 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1834 
1835 	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
1836 	       (los_options == los_normal && event == SFP_E_LOS_LOW);
1837 }
1838 
1839 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1840 {
1841 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
1842 		dev_err(sfp->dev,
1843 			"module persistently indicates fault, disabling\n");
1844 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1845 	} else {
1846 		if (warn)
1847 			dev_err(sfp->dev, "module transmit fault indicated\n");
1848 
1849 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1850 	}
1851 }
1852 
1853 static int sfp_sm_add_mdio_bus(struct sfp *sfp)
1854 {
1855 	if (sfp->mdio_protocol != MDIO_I2C_NONE)
1856 		return sfp_i2c_mdiobus_create(sfp);
1857 
1858 	return 0;
1859 }
1860 
1861 /* Probe a SFP for a PHY device if the module supports copper - the PHY
1862  * normally sits at I2C bus address 0x56, and may either be a clause 22
1863  * or clause 45 PHY.
1864  *
1865  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
1866  * negotiation enabled, but some may be in 1000base-X - which is for the
1867  * PHY driver to determine.
1868  *
1869  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
1870  * mode according to the negotiated line speed.
1871  */
1872 static int sfp_sm_probe_for_phy(struct sfp *sfp)
1873 {
1874 	int err = 0;
1875 
1876 	switch (sfp->mdio_protocol) {
1877 	case MDIO_I2C_NONE:
1878 		break;
1879 
1880 	case MDIO_I2C_MARVELL_C22:
1881 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, false);
1882 		break;
1883 
1884 	case MDIO_I2C_C45:
1885 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, true);
1886 		break;
1887 
1888 	case MDIO_I2C_ROLLBALL:
1889 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR_ROLLBALL, true);
1890 		break;
1891 	}
1892 
1893 	return err;
1894 }
1895 
1896 static int sfp_module_parse_power(struct sfp *sfp)
1897 {
1898 	u32 power_mW = 1000;
1899 	bool supports_a2;
1900 
1901 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
1902 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1903 		power_mW = 1500;
1904 	/* Added in Rev 11.9, but there is no compliance code for this */
1905 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV11_4 &&
1906 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1907 		power_mW = 2000;
1908 
1909 	/* Power level 1 modules (max. 1W) are always supported. */
1910 	if (power_mW <= 1000) {
1911 		sfp->module_power_mW = power_mW;
1912 		return 0;
1913 	}
1914 
1915 	supports_a2 = sfp->id.ext.sff8472_compliance !=
1916 				SFP_SFF8472_COMPLIANCE_NONE ||
1917 		      sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
1918 
1919 	if (power_mW > sfp->max_power_mW) {
1920 		/* Module power specification exceeds the allowed maximum. */
1921 		if (!supports_a2) {
1922 			/* The module appears not to implement bus address
1923 			 * 0xa2, so assume that the module powers up in the
1924 			 * indicated mode.
1925 			 */
1926 			dev_err(sfp->dev,
1927 				"Host does not support %u.%uW modules\n",
1928 				power_mW / 1000, (power_mW / 100) % 10);
1929 			return -EINVAL;
1930 		} else {
1931 			dev_warn(sfp->dev,
1932 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1933 				 power_mW / 1000, (power_mW / 100) % 10);
1934 			return 0;
1935 		}
1936 	}
1937 
1938 	if (!supports_a2) {
1939 		/* The module power level is below the host maximum and the
1940 		 * module appears not to implement bus address 0xa2, so assume
1941 		 * that the module powers up in the indicated mode.
1942 		 */
1943 		return 0;
1944 	}
1945 
1946 	/* If the module requires a higher power mode, but also requires
1947 	 * an address change sequence, warn the user that the module may
1948 	 * not be functional.
1949 	 */
1950 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
1951 		dev_warn(sfp->dev,
1952 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1953 			 power_mW / 1000, (power_mW / 100) % 10);
1954 		return 0;
1955 	}
1956 
1957 	sfp->module_power_mW = power_mW;
1958 
1959 	return 0;
1960 }
1961 
1962 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1963 {
1964 	int err;
1965 
1966 	err = sfp_modify_u8(sfp, true, SFP_EXT_STATUS,
1967 			    SFP_EXT_STATUS_PWRLVL_SELECT,
1968 			    enable ? SFP_EXT_STATUS_PWRLVL_SELECT : 0);
1969 	if (err != sizeof(u8)) {
1970 		dev_err(sfp->dev, "failed to %sable high power: %pe\n",
1971 			enable ? "en" : "dis", ERR_PTR(err));
1972 		return -EAGAIN;
1973 	}
1974 
1975 	if (enable)
1976 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1977 			 sfp->module_power_mW / 1000,
1978 			 (sfp->module_power_mW / 100) % 10);
1979 
1980 	return 0;
1981 }
1982 
1983 static void sfp_module_parse_rate_select(struct sfp *sfp)
1984 {
1985 	u8 rate_id;
1986 
1987 	sfp->rs_threshold_kbd = 0;
1988 	sfp->rs_state_mask = 0;
1989 
1990 	if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_RATE_SELECT)))
1991 		/* No support for RateSelect */
1992 		return;
1993 
1994 	/* Default to INF-8074 RateSelect operation. The signalling threshold
1995 	 * rate is not well specified, so always select "Full Bandwidth", but
1996 	 * SFF-8079 reveals that it is understood that RS0 will be low for
1997 	 * 1.0625Gb/s and high for 2.125Gb/s. Choose a value half-way between.
1998 	 * This method exists prior to SFF-8472.
1999 	 */
2000 	sfp->rs_state_mask = SFP_F_RS0;
2001 	sfp->rs_threshold_kbd = 1594;
2002 
2003 	/* Parse the rate identifier, which is complicated due to history:
2004 	 * SFF-8472 rev 9.5 marks this field as reserved.
2005 	 * SFF-8079 references SFF-8472 rev 9.5 and defines bit 0. SFF-8472
2006 	 *  compliance is not required.
2007 	 * SFF-8472 rev 10.2 defines this field using values 0..4
2008 	 * SFF-8472 rev 11.0 redefines this field with bit 0 for SFF-8079
2009 	 * and even values.
2010 	 */
2011 	rate_id = sfp->id.base.rate_id;
2012 	if (rate_id == 0)
2013 		/* Unspecified */
2014 		return;
2015 
2016 	/* SFF-8472 rev 10.0..10.4 did not account for SFF-8079 using bit 0,
2017 	 * and allocated value 3 to SFF-8431 independent tx/rx rate select.
2018 	 * Convert this to a SFF-8472 rev 11.0 rate identifier.
2019 	 */
2020 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
2021 	    sfp->id.ext.sff8472_compliance < SFP_SFF8472_COMPLIANCE_REV11_0 &&
2022 	    rate_id == 3)
2023 		rate_id = SFF_RID_8431;
2024 
2025 	if (rate_id & SFF_RID_8079) {
2026 		/* SFF-8079 RateSelect / Application Select in conjunction with
2027 		 * SFF-8472 rev 9.5. SFF-8079 defines rate_id as a bitfield
2028 		 * with only bit 0 used, which takes precedence over SFF-8472.
2029 		 */
2030 		if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_APP_SELECT_SFF8079)) {
2031 			/* SFF-8079 Part 1 - rate selection between Fibre
2032 			 * Channel 1.0625/2.125/4.25 Gbd modes. Note that RS0
2033 			 * is high for 2125, so we have to subtract 1 to
2034 			 * include it.
2035 			 */
2036 			sfp->rs_threshold_kbd = 2125 - 1;
2037 			sfp->rs_state_mask = SFP_F_RS0;
2038 		}
2039 		return;
2040 	}
2041 
2042 	/* SFF-8472 rev 9.5 does not define the rate identifier */
2043 	if (sfp->id.ext.sff8472_compliance <= SFP_SFF8472_COMPLIANCE_REV9_5)
2044 		return;
2045 
2046 	/* SFF-8472 rev 11.0 defines rate_id as a numerical value which will
2047 	 * always have bit 0 clear due to SFF-8079's bitfield usage of rate_id.
2048 	 */
2049 	switch (rate_id) {
2050 	case SFF_RID_8431_RX_ONLY:
2051 		sfp->rs_threshold_kbd = 4250;
2052 		sfp->rs_state_mask = SFP_F_RS0;
2053 		break;
2054 
2055 	case SFF_RID_8431_TX_ONLY:
2056 		sfp->rs_threshold_kbd = 4250;
2057 		sfp->rs_state_mask = SFP_F_RS1;
2058 		break;
2059 
2060 	case SFF_RID_8431:
2061 		sfp->rs_threshold_kbd = 4250;
2062 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2063 		break;
2064 
2065 	case SFF_RID_10G8G:
2066 		sfp->rs_threshold_kbd = 9000;
2067 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2068 		break;
2069 	}
2070 }
2071 
2072 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
2073  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
2074  * not support multibyte reads from the EEPROM. Each multi-byte read
2075  * operation returns just one byte of EEPROM followed by zeros. There is
2076  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
2077  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
2078  * name and vendor id into EEPROM, so there is even no way to detect if
2079  * module is V-SOL V2801F. Therefore check for those zeros in the read
2080  * data and then based on check switch to reading EEPROM to one byte
2081  * at a time.
2082  */
2083 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
2084 {
2085 	size_t i, block_size = sfp->i2c_block_size;
2086 
2087 	/* Already using byte IO */
2088 	if (block_size == 1)
2089 		return false;
2090 
2091 	for (i = 1; i < len; i += block_size) {
2092 		if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
2093 			return false;
2094 	}
2095 	return true;
2096 }
2097 
2098 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
2099 {
2100 	u8 check;
2101 	int err;
2102 
2103 	if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
2104 	    id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
2105 	    id->base.connector != SFF8024_CONNECTOR_LC) {
2106 		dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
2107 		id->base.phys_id = SFF8024_ID_SFF_8472;
2108 		id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
2109 		id->base.connector = SFF8024_CONNECTOR_LC;
2110 		err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
2111 		if (err != 3) {
2112 			dev_err(sfp->dev,
2113 				"Failed to rewrite module EEPROM: %pe\n",
2114 				ERR_PTR(err));
2115 			return err;
2116 		}
2117 
2118 		/* Cotsworks modules have been found to require a delay between write operations. */
2119 		mdelay(50);
2120 
2121 		/* Update base structure checksum */
2122 		check = sfp_check(&id->base, sizeof(id->base) - 1);
2123 		err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
2124 		if (err != 1) {
2125 			dev_err(sfp->dev,
2126 				"Failed to update base structure checksum in fiber module EEPROM: %pe\n",
2127 				ERR_PTR(err));
2128 			return err;
2129 		}
2130 	}
2131 	return 0;
2132 }
2133 
2134 static int sfp_module_parse_sff8472(struct sfp *sfp)
2135 {
2136 	/* If the module requires address swap mode, warn about it */
2137 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
2138 		dev_warn(sfp->dev,
2139 			 "module address swap to access page 0xA2 is not supported.\n");
2140 	else
2141 		sfp->have_a2 = true;
2142 
2143 	return 0;
2144 }
2145 
2146 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
2147 {
2148 	/* SFP module inserted - read I2C data */
2149 	struct sfp_eeprom_id id;
2150 	bool cotsworks_sfbg;
2151 	unsigned int mask;
2152 	bool cotsworks;
2153 	u8 check;
2154 	int ret;
2155 
2156 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2157 
2158 	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2159 	if (ret < 0) {
2160 		if (report)
2161 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2162 				ERR_PTR(ret));
2163 		return -EAGAIN;
2164 	}
2165 
2166 	if (ret != sizeof(id.base)) {
2167 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2168 		return -EAGAIN;
2169 	}
2170 
2171 	/* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
2172 	 * address 0x51 is just one byte at a time. Also SFF-8472 requires
2173 	 * that EEPROM supports atomic 16bit read operation for diagnostic
2174 	 * fields, so do not switch to one byte reading at a time unless it
2175 	 * is really required and we have no other option.
2176 	 */
2177 	if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
2178 		dev_info(sfp->dev,
2179 			 "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
2180 		dev_info(sfp->dev,
2181 			 "Switching to reading EEPROM to one byte at a time\n");
2182 		sfp->i2c_block_size = 1;
2183 
2184 		ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2185 		if (ret < 0) {
2186 			if (report)
2187 				dev_err(sfp->dev,
2188 					"failed to read EEPROM: %pe\n",
2189 					ERR_PTR(ret));
2190 			return -EAGAIN;
2191 		}
2192 
2193 		if (ret != sizeof(id.base)) {
2194 			dev_err(sfp->dev, "EEPROM short read: %pe\n",
2195 				ERR_PTR(ret));
2196 			return -EAGAIN;
2197 		}
2198 	}
2199 
2200 	/* Cotsworks do not seem to update the checksums when they
2201 	 * do the final programming with the final module part number,
2202 	 * serial number and date code.
2203 	 */
2204 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
2205 	cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
2206 
2207 	/* Cotsworks SFF module EEPROM do not always have valid phys_id,
2208 	 * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
2209 	 * Cotsworks PN matches and bytes are not correct.
2210 	 */
2211 	if (cotsworks && cotsworks_sfbg) {
2212 		ret = sfp_cotsworks_fixup_check(sfp, &id);
2213 		if (ret < 0)
2214 			return ret;
2215 	}
2216 
2217 	/* Validate the checksum over the base structure */
2218 	check = sfp_check(&id.base, sizeof(id.base) - 1);
2219 	if (check != id.base.cc_base) {
2220 		if (cotsworks) {
2221 			dev_warn(sfp->dev,
2222 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
2223 				 check, id.base.cc_base);
2224 		} else {
2225 			dev_err(sfp->dev,
2226 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
2227 				check, id.base.cc_base);
2228 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2229 				       16, 1, &id, sizeof(id), true);
2230 			return -EINVAL;
2231 		}
2232 	}
2233 
2234 	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
2235 	if (ret < 0) {
2236 		if (report)
2237 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2238 				ERR_PTR(ret));
2239 		return -EAGAIN;
2240 	}
2241 
2242 	if (ret != sizeof(id.ext)) {
2243 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2244 		return -EAGAIN;
2245 	}
2246 
2247 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
2248 	if (check != id.ext.cc_ext) {
2249 		if (cotsworks) {
2250 			dev_warn(sfp->dev,
2251 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
2252 				 check, id.ext.cc_ext);
2253 		} else {
2254 			dev_err(sfp->dev,
2255 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
2256 				check, id.ext.cc_ext);
2257 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2258 				       16, 1, &id, sizeof(id), true);
2259 			memset(&id.ext, 0, sizeof(id.ext));
2260 		}
2261 	}
2262 
2263 	sfp->id = id;
2264 
2265 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
2266 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
2267 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
2268 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
2269 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
2270 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
2271 
2272 	/* Check whether we support this module */
2273 	if (!sfp->type->module_supported(&id)) {
2274 		dev_err(sfp->dev,
2275 			"module is not supported - phys id 0x%02x 0x%02x\n",
2276 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
2277 		return -EINVAL;
2278 	}
2279 
2280 	if (sfp->id.ext.sff8472_compliance != SFP_SFF8472_COMPLIANCE_NONE) {
2281 		ret = sfp_module_parse_sff8472(sfp);
2282 		if (ret < 0)
2283 			return ret;
2284 	}
2285 
2286 	/* Parse the module power requirement */
2287 	ret = sfp_module_parse_power(sfp);
2288 	if (ret < 0)
2289 		return ret;
2290 
2291 	sfp_module_parse_rate_select(sfp);
2292 
2293 	mask = SFP_F_PRESENT;
2294 	if (sfp->gpio[GPIO_TX_DISABLE])
2295 		mask |= SFP_F_TX_DISABLE;
2296 	if (sfp->gpio[GPIO_TX_FAULT])
2297 		mask |= SFP_F_TX_FAULT;
2298 	if (sfp->gpio[GPIO_LOS])
2299 		mask |= SFP_F_LOS;
2300 	if (sfp->gpio[GPIO_RS0])
2301 		mask |= SFP_F_RS0;
2302 	if (sfp->gpio[GPIO_RS1])
2303 		mask |= SFP_F_RS1;
2304 
2305 	sfp->module_t_start_up = T_START_UP;
2306 	sfp->module_t_wait = T_WAIT;
2307 
2308 	sfp->tx_fault_ignore = false;
2309 
2310 	if (sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SFI ||
2311 	    sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SR ||
2312 	    sfp->id.base.extended_cc == SFF8024_ECC_5GBASE_T ||
2313 	    sfp->id.base.extended_cc == SFF8024_ECC_2_5GBASE_T)
2314 		sfp->mdio_protocol = MDIO_I2C_C45;
2315 	else if (sfp->id.base.e1000_base_t)
2316 		sfp->mdio_protocol = MDIO_I2C_MARVELL_C22;
2317 	else
2318 		sfp->mdio_protocol = MDIO_I2C_NONE;
2319 
2320 	sfp->quirk = sfp_lookup_quirk(&id);
2321 
2322 	mutex_lock(&sfp->st_mutex);
2323 	/* Initialise state bits to use from hardware */
2324 	sfp->state_hw_mask = mask;
2325 
2326 	/* We want to drive the rate select pins that the module is using */
2327 	sfp->state_hw_drive |= sfp->rs_state_mask;
2328 
2329 	if (sfp->quirk && sfp->quirk->fixup)
2330 		sfp->quirk->fixup(sfp);
2331 	mutex_unlock(&sfp->st_mutex);
2332 
2333 	return 0;
2334 }
2335 
2336 static void sfp_sm_mod_remove(struct sfp *sfp)
2337 {
2338 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
2339 		sfp_module_remove(sfp->sfp_bus);
2340 
2341 	sfp_hwmon_remove(sfp);
2342 
2343 	memset(&sfp->id, 0, sizeof(sfp->id));
2344 	sfp->module_power_mW = 0;
2345 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
2346 	sfp->have_a2 = false;
2347 
2348 	dev_info(sfp->dev, "module removed\n");
2349 }
2350 
2351 /* This state machine tracks the upstream's state */
2352 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
2353 {
2354 	switch (sfp->sm_dev_state) {
2355 	default:
2356 		if (event == SFP_E_DEV_ATTACH)
2357 			sfp->sm_dev_state = SFP_DEV_DOWN;
2358 		break;
2359 
2360 	case SFP_DEV_DOWN:
2361 		if (event == SFP_E_DEV_DETACH)
2362 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2363 		else if (event == SFP_E_DEV_UP)
2364 			sfp->sm_dev_state = SFP_DEV_UP;
2365 		break;
2366 
2367 	case SFP_DEV_UP:
2368 		if (event == SFP_E_DEV_DETACH)
2369 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2370 		else if (event == SFP_E_DEV_DOWN)
2371 			sfp->sm_dev_state = SFP_DEV_DOWN;
2372 		break;
2373 	}
2374 }
2375 
2376 /* This state machine tracks the insert/remove state of the module, probes
2377  * the on-board EEPROM, and sets up the power level.
2378  */
2379 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
2380 {
2381 	int err;
2382 
2383 	/* Handle remove event globally, it resets this state machine */
2384 	if (event == SFP_E_REMOVE) {
2385 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
2386 			sfp_sm_mod_remove(sfp);
2387 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
2388 		return;
2389 	}
2390 
2391 	/* Handle device detach globally */
2392 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
2393 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
2394 		if (sfp->module_power_mW > 1000 &&
2395 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
2396 			sfp_sm_mod_hpower(sfp, false);
2397 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2398 		return;
2399 	}
2400 
2401 	switch (sfp->sm_mod_state) {
2402 	default:
2403 		if (event == SFP_E_INSERT) {
2404 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
2405 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
2406 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
2407 		}
2408 		break;
2409 
2410 	case SFP_MOD_PROBE:
2411 		/* Wait for T_PROBE_INIT to time out */
2412 		if (event != SFP_E_TIMEOUT)
2413 			break;
2414 
2415 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
2416 		if (err == -EAGAIN) {
2417 			if (sfp->sm_mod_tries_init &&
2418 			   --sfp->sm_mod_tries_init) {
2419 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2420 				break;
2421 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
2422 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
2423 					dev_warn(sfp->dev,
2424 						 "please wait, module slow to respond\n");
2425 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
2426 				break;
2427 			}
2428 		}
2429 		if (err < 0) {
2430 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2431 			break;
2432 		}
2433 
2434 		/* Force a poll to re-read the hardware signal state after
2435 		 * sfp_sm_mod_probe() changed state_hw_mask.
2436 		 */
2437 		mod_delayed_work(system_wq, &sfp->poll, 1);
2438 
2439 		err = sfp_hwmon_insert(sfp);
2440 		if (err)
2441 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
2442 				 ERR_PTR(err));
2443 
2444 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2445 		fallthrough;
2446 	case SFP_MOD_WAITDEV:
2447 		/* Ensure that the device is attached before proceeding */
2448 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
2449 			break;
2450 
2451 		/* Report the module insertion to the upstream device */
2452 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id,
2453 					sfp->quirk);
2454 		if (err < 0) {
2455 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2456 			break;
2457 		}
2458 
2459 		/* If this is a power level 1 module, we are done */
2460 		if (sfp->module_power_mW <= 1000)
2461 			goto insert;
2462 
2463 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
2464 		fallthrough;
2465 	case SFP_MOD_HPOWER:
2466 		/* Enable high power mode */
2467 		err = sfp_sm_mod_hpower(sfp, true);
2468 		if (err < 0) {
2469 			if (err != -EAGAIN) {
2470 				sfp_module_remove(sfp->sfp_bus);
2471 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2472 			} else {
2473 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2474 			}
2475 			break;
2476 		}
2477 
2478 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
2479 		break;
2480 
2481 	case SFP_MOD_WAITPWR:
2482 		/* Wait for T_HPOWER_LEVEL to time out */
2483 		if (event != SFP_E_TIMEOUT)
2484 			break;
2485 
2486 	insert:
2487 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
2488 		break;
2489 
2490 	case SFP_MOD_PRESENT:
2491 	case SFP_MOD_ERROR:
2492 		break;
2493 	}
2494 }
2495 
2496 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
2497 {
2498 	unsigned long timeout;
2499 	int ret;
2500 
2501 	/* Some events are global */
2502 	if (sfp->sm_state != SFP_S_DOWN &&
2503 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2504 	     sfp->sm_dev_state != SFP_DEV_UP)) {
2505 		if (sfp->sm_state == SFP_S_LINK_UP &&
2506 		    sfp->sm_dev_state == SFP_DEV_UP)
2507 			sfp_sm_link_down(sfp);
2508 		if (sfp->sm_state > SFP_S_INIT)
2509 			sfp_module_stop(sfp->sfp_bus);
2510 		if (sfp->mod_phy)
2511 			sfp_sm_phy_detach(sfp);
2512 		if (sfp->i2c_mii)
2513 			sfp_i2c_mdiobus_destroy(sfp);
2514 		sfp_module_tx_disable(sfp);
2515 		sfp_soft_stop_poll(sfp);
2516 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
2517 		return;
2518 	}
2519 
2520 	/* The main state machine */
2521 	switch (sfp->sm_state) {
2522 	case SFP_S_DOWN:
2523 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2524 		    sfp->sm_dev_state != SFP_DEV_UP)
2525 			break;
2526 
2527 		/* Only use the soft state bits if we have access to the A2h
2528 		 * memory, which implies that we have some level of SFF-8472
2529 		 * compliance.
2530 		 */
2531 		if (sfp->have_a2)
2532 			sfp_soft_start_poll(sfp);
2533 
2534 		sfp_module_tx_enable(sfp);
2535 
2536 		/* Initialise the fault clearance retries */
2537 		sfp->sm_fault_retries = N_FAULT_INIT;
2538 
2539 		/* We need to check the TX_FAULT state, which is not defined
2540 		 * while TX_DISABLE is asserted. The earliest we want to do
2541 		 * anything (such as probe for a PHY) is 50ms (or more on
2542 		 * specific modules).
2543 		 */
2544 		sfp_sm_next(sfp, SFP_S_WAIT, sfp->module_t_wait);
2545 		break;
2546 
2547 	case SFP_S_WAIT:
2548 		if (event != SFP_E_TIMEOUT)
2549 			break;
2550 
2551 		if (sfp->state & SFP_F_TX_FAULT) {
2552 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
2553 			 * from the TX_DISABLE deassertion for the module to
2554 			 * initialise, which is indicated by TX_FAULT
2555 			 * deasserting.
2556 			 */
2557 			timeout = sfp->module_t_start_up;
2558 			if (timeout > sfp->module_t_wait)
2559 				timeout -= sfp->module_t_wait;
2560 			else
2561 				timeout = 1;
2562 
2563 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
2564 		} else {
2565 			/* TX_FAULT is not asserted, assume the module has
2566 			 * finished initialising.
2567 			 */
2568 			goto init_done;
2569 		}
2570 		break;
2571 
2572 	case SFP_S_INIT:
2573 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2574 			/* TX_FAULT is still asserted after t_init
2575 			 * or t_start_up, so assume there is a fault.
2576 			 */
2577 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
2578 				     sfp->sm_fault_retries == N_FAULT_INIT);
2579 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2580 	init_done:
2581 			/* Create mdiobus and start trying for PHY */
2582 			ret = sfp_sm_add_mdio_bus(sfp);
2583 			if (ret < 0) {
2584 				sfp_sm_next(sfp, SFP_S_FAIL, 0);
2585 				break;
2586 			}
2587 			sfp->sm_phy_retries = R_PHY_RETRY;
2588 			goto phy_probe;
2589 		}
2590 		break;
2591 
2592 	case SFP_S_INIT_PHY:
2593 		if (event != SFP_E_TIMEOUT)
2594 			break;
2595 	phy_probe:
2596 		/* TX_FAULT deasserted or we timed out with TX_FAULT
2597 		 * clear.  Probe for the PHY and check the LOS state.
2598 		 */
2599 		ret = sfp_sm_probe_for_phy(sfp);
2600 		if (ret == -ENODEV) {
2601 			if (--sfp->sm_phy_retries) {
2602 				sfp_sm_next(sfp, SFP_S_INIT_PHY, T_PHY_RETRY);
2603 				break;
2604 			} else {
2605 				dev_info(sfp->dev, "no PHY detected\n");
2606 			}
2607 		} else if (ret) {
2608 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2609 			break;
2610 		}
2611 		if (sfp_module_start(sfp->sfp_bus)) {
2612 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2613 			break;
2614 		}
2615 		sfp_sm_link_check_los(sfp);
2616 
2617 		/* Reset the fault retry count */
2618 		sfp->sm_fault_retries = N_FAULT;
2619 		break;
2620 
2621 	case SFP_S_INIT_TX_FAULT:
2622 		if (event == SFP_E_TIMEOUT) {
2623 			sfp_module_tx_fault_reset(sfp);
2624 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
2625 		}
2626 		break;
2627 
2628 	case SFP_S_WAIT_LOS:
2629 		if (event == SFP_E_TX_FAULT)
2630 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2631 		else if (sfp_los_event_inactive(sfp, event))
2632 			sfp_sm_link_up(sfp);
2633 		break;
2634 
2635 	case SFP_S_LINK_UP:
2636 		if (event == SFP_E_TX_FAULT) {
2637 			sfp_sm_link_down(sfp);
2638 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2639 		} else if (sfp_los_event_active(sfp, event)) {
2640 			sfp_sm_link_down(sfp);
2641 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2642 		}
2643 		break;
2644 
2645 	case SFP_S_TX_FAULT:
2646 		if (event == SFP_E_TIMEOUT) {
2647 			sfp_module_tx_fault_reset(sfp);
2648 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2649 		}
2650 		break;
2651 
2652 	case SFP_S_REINIT:
2653 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2654 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2655 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2656 			dev_info(sfp->dev, "module transmit fault recovered\n");
2657 			sfp_sm_link_check_los(sfp);
2658 		}
2659 		break;
2660 
2661 	case SFP_S_TX_DISABLE:
2662 		break;
2663 	}
2664 }
2665 
2666 static void __sfp_sm_event(struct sfp *sfp, unsigned int event)
2667 {
2668 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
2669 		mod_state_to_str(sfp->sm_mod_state),
2670 		dev_state_to_str(sfp->sm_dev_state),
2671 		sm_state_to_str(sfp->sm_state),
2672 		event_to_str(event));
2673 
2674 	sfp_sm_device(sfp, event);
2675 	sfp_sm_module(sfp, event);
2676 	sfp_sm_main(sfp, event);
2677 
2678 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
2679 		mod_state_to_str(sfp->sm_mod_state),
2680 		dev_state_to_str(sfp->sm_dev_state),
2681 		sm_state_to_str(sfp->sm_state));
2682 }
2683 
2684 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
2685 {
2686 	mutex_lock(&sfp->sm_mutex);
2687 	__sfp_sm_event(sfp, event);
2688 	mutex_unlock(&sfp->sm_mutex);
2689 }
2690 
2691 static void sfp_attach(struct sfp *sfp)
2692 {
2693 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
2694 }
2695 
2696 static void sfp_detach(struct sfp *sfp)
2697 {
2698 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
2699 }
2700 
2701 static void sfp_start(struct sfp *sfp)
2702 {
2703 	sfp_sm_event(sfp, SFP_E_DEV_UP);
2704 }
2705 
2706 static void sfp_stop(struct sfp *sfp)
2707 {
2708 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
2709 }
2710 
2711 static void sfp_set_signal_rate(struct sfp *sfp, unsigned int rate_kbd)
2712 {
2713 	unsigned int set;
2714 
2715 	sfp->rate_kbd = rate_kbd;
2716 
2717 	if (rate_kbd > sfp->rs_threshold_kbd)
2718 		set = sfp->rs_state_mask;
2719 	else
2720 		set = 0;
2721 
2722 	sfp_mod_state(sfp, SFP_F_RS0 | SFP_F_RS1, set);
2723 }
2724 
2725 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2726 {
2727 	/* locking... and check module is present */
2728 
2729 	if (sfp->id.ext.sff8472_compliance &&
2730 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2731 		modinfo->type = ETH_MODULE_SFF_8472;
2732 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2733 	} else {
2734 		modinfo->type = ETH_MODULE_SFF_8079;
2735 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2736 	}
2737 	return 0;
2738 }
2739 
2740 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2741 			     u8 *data)
2742 {
2743 	unsigned int first, last, len;
2744 	int ret;
2745 
2746 	if (!(sfp->state & SFP_F_PRESENT))
2747 		return -ENODEV;
2748 
2749 	if (ee->len == 0)
2750 		return -EINVAL;
2751 
2752 	first = ee->offset;
2753 	last = ee->offset + ee->len;
2754 	if (first < ETH_MODULE_SFF_8079_LEN) {
2755 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2756 		len -= first;
2757 
2758 		ret = sfp_read(sfp, false, first, data, len);
2759 		if (ret < 0)
2760 			return ret;
2761 
2762 		first += len;
2763 		data += len;
2764 	}
2765 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2766 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2767 		len -= first;
2768 		first -= ETH_MODULE_SFF_8079_LEN;
2769 
2770 		ret = sfp_read(sfp, true, first, data, len);
2771 		if (ret < 0)
2772 			return ret;
2773 	}
2774 	return 0;
2775 }
2776 
2777 static int sfp_module_eeprom_by_page(struct sfp *sfp,
2778 				     const struct ethtool_module_eeprom *page,
2779 				     struct netlink_ext_ack *extack)
2780 {
2781 	if (!(sfp->state & SFP_F_PRESENT))
2782 		return -ENODEV;
2783 
2784 	if (page->bank) {
2785 		NL_SET_ERR_MSG(extack, "Banks not supported");
2786 		return -EOPNOTSUPP;
2787 	}
2788 
2789 	if (page->page) {
2790 		NL_SET_ERR_MSG(extack, "Only page 0 supported");
2791 		return -EOPNOTSUPP;
2792 	}
2793 
2794 	if (page->i2c_address != 0x50 &&
2795 	    page->i2c_address != 0x51) {
2796 		NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
2797 		return -EOPNOTSUPP;
2798 	}
2799 
2800 	return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
2801 			page->data, page->length);
2802 };
2803 
2804 static const struct sfp_socket_ops sfp_module_ops = {
2805 	.attach = sfp_attach,
2806 	.detach = sfp_detach,
2807 	.start = sfp_start,
2808 	.stop = sfp_stop,
2809 	.set_signal_rate = sfp_set_signal_rate,
2810 	.module_info = sfp_module_info,
2811 	.module_eeprom = sfp_module_eeprom,
2812 	.module_eeprom_by_page = sfp_module_eeprom_by_page,
2813 };
2814 
2815 static void sfp_timeout(struct work_struct *work)
2816 {
2817 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2818 
2819 	rtnl_lock();
2820 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2821 	rtnl_unlock();
2822 }
2823 
2824 static void sfp_check_state(struct sfp *sfp)
2825 {
2826 	unsigned int state, i, changed;
2827 
2828 	rtnl_lock();
2829 	mutex_lock(&sfp->st_mutex);
2830 	state = sfp_get_state(sfp);
2831 	changed = state ^ sfp->state;
2832 	if (sfp->tx_fault_ignore)
2833 		changed &= SFP_F_PRESENT | SFP_F_LOS;
2834 	else
2835 		changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2836 
2837 	for (i = 0; i < GPIO_MAX; i++)
2838 		if (changed & BIT(i))
2839 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_names[i],
2840 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2841 
2842 	state |= sfp->state & SFP_F_OUTPUTS;
2843 	sfp->state = state;
2844 	mutex_unlock(&sfp->st_mutex);
2845 
2846 	mutex_lock(&sfp->sm_mutex);
2847 	if (changed & SFP_F_PRESENT)
2848 		__sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2849 				    SFP_E_INSERT : SFP_E_REMOVE);
2850 
2851 	if (changed & SFP_F_TX_FAULT)
2852 		__sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2853 				    SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2854 
2855 	if (changed & SFP_F_LOS)
2856 		__sfp_sm_event(sfp, state & SFP_F_LOS ?
2857 				    SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2858 	mutex_unlock(&sfp->sm_mutex);
2859 	rtnl_unlock();
2860 }
2861 
2862 static irqreturn_t sfp_irq(int irq, void *data)
2863 {
2864 	struct sfp *sfp = data;
2865 
2866 	sfp_check_state(sfp);
2867 
2868 	return IRQ_HANDLED;
2869 }
2870 
2871 static void sfp_poll(struct work_struct *work)
2872 {
2873 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2874 
2875 	sfp_check_state(sfp);
2876 
2877 	// st_mutex doesn't need to be held here for state_soft_mask,
2878 	// it's unimportant if we race while reading this.
2879 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2880 	    sfp->need_poll)
2881 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2882 }
2883 
2884 static struct sfp *sfp_alloc(struct device *dev)
2885 {
2886 	struct sfp *sfp;
2887 
2888 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2889 	if (!sfp)
2890 		return ERR_PTR(-ENOMEM);
2891 
2892 	sfp->dev = dev;
2893 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2894 
2895 	mutex_init(&sfp->sm_mutex);
2896 	mutex_init(&sfp->st_mutex);
2897 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2898 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2899 
2900 	sfp_hwmon_init(sfp);
2901 
2902 	return sfp;
2903 }
2904 
2905 static void sfp_cleanup(void *data)
2906 {
2907 	struct sfp *sfp = data;
2908 
2909 	sfp_hwmon_exit(sfp);
2910 
2911 	cancel_delayed_work_sync(&sfp->poll);
2912 	cancel_delayed_work_sync(&sfp->timeout);
2913 	if (sfp->i2c_mii) {
2914 		mdiobus_unregister(sfp->i2c_mii);
2915 		mdiobus_free(sfp->i2c_mii);
2916 	}
2917 	if (sfp->i2c)
2918 		i2c_put_adapter(sfp->i2c);
2919 	kfree(sfp);
2920 }
2921 
2922 static int sfp_i2c_get(struct sfp *sfp)
2923 {
2924 	struct fwnode_handle *h;
2925 	struct i2c_adapter *i2c;
2926 	int err;
2927 
2928 	h = fwnode_find_reference(dev_fwnode(sfp->dev), "i2c-bus", 0);
2929 	if (IS_ERR(h)) {
2930 		dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2931 		return -ENODEV;
2932 	}
2933 
2934 	i2c = i2c_get_adapter_by_fwnode(h);
2935 	if (!i2c) {
2936 		err = -EPROBE_DEFER;
2937 		goto put;
2938 	}
2939 
2940 	err = sfp_i2c_configure(sfp, i2c);
2941 	if (err)
2942 		i2c_put_adapter(i2c);
2943 put:
2944 	fwnode_handle_put(h);
2945 	return err;
2946 }
2947 
2948 static int sfp_probe(struct platform_device *pdev)
2949 {
2950 	const struct sff_data *sff;
2951 	char *sfp_irq_name;
2952 	struct sfp *sfp;
2953 	int err, i;
2954 
2955 	sfp = sfp_alloc(&pdev->dev);
2956 	if (IS_ERR(sfp))
2957 		return PTR_ERR(sfp);
2958 
2959 	platform_set_drvdata(pdev, sfp);
2960 
2961 	err = devm_add_action_or_reset(sfp->dev, sfp_cleanup, sfp);
2962 	if (err < 0)
2963 		return err;
2964 
2965 	sff = device_get_match_data(sfp->dev);
2966 	if (!sff)
2967 		sff = &sfp_data;
2968 
2969 	sfp->type = sff;
2970 
2971 	err = sfp_i2c_get(sfp);
2972 	if (err)
2973 		return err;
2974 
2975 	for (i = 0; i < GPIO_MAX; i++)
2976 		if (sff->gpios & BIT(i)) {
2977 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
2978 					   gpio_names[i], gpio_flags[i]);
2979 			if (IS_ERR(sfp->gpio[i]))
2980 				return PTR_ERR(sfp->gpio[i]);
2981 		}
2982 
2983 	sfp->state_hw_mask = SFP_F_PRESENT;
2984 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
2985 
2986 	sfp->get_state = sfp_gpio_get_state;
2987 	sfp->set_state = sfp_gpio_set_state;
2988 
2989 	/* Modules that have no detect signal are always present */
2990 	if (!(sfp->gpio[GPIO_MODDEF0]))
2991 		sfp->get_state = sff_gpio_get_state;
2992 
2993 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
2994 				 &sfp->max_power_mW);
2995 	if (sfp->max_power_mW < 1000) {
2996 		if (sfp->max_power_mW)
2997 			dev_warn(sfp->dev,
2998 				 "Firmware bug: host maximum power should be at least 1W\n");
2999 		sfp->max_power_mW = 1000;
3000 	}
3001 
3002 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
3003 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
3004 
3005 	/* Get the initial state, and always signal TX disable,
3006 	 * since the network interface will not be up.
3007 	 */
3008 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
3009 
3010 	if (sfp->gpio[GPIO_RS0] &&
3011 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RS0]))
3012 		sfp->state |= SFP_F_RS0;
3013 	sfp_set_state(sfp, sfp->state);
3014 	sfp_module_tx_disable(sfp);
3015 	if (sfp->state & SFP_F_PRESENT) {
3016 		rtnl_lock();
3017 		sfp_sm_event(sfp, SFP_E_INSERT);
3018 		rtnl_unlock();
3019 	}
3020 
3021 	for (i = 0; i < GPIO_MAX; i++) {
3022 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
3023 			continue;
3024 
3025 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
3026 		if (sfp->gpio_irq[i] < 0) {
3027 			sfp->gpio_irq[i] = 0;
3028 			sfp->need_poll = true;
3029 			continue;
3030 		}
3031 
3032 		sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
3033 					      "%s-%s", dev_name(sfp->dev),
3034 					      gpio_names[i]);
3035 
3036 		if (!sfp_irq_name)
3037 			return -ENOMEM;
3038 
3039 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
3040 						NULL, sfp_irq,
3041 						IRQF_ONESHOT |
3042 						IRQF_TRIGGER_RISING |
3043 						IRQF_TRIGGER_FALLING,
3044 						sfp_irq_name, sfp);
3045 		if (err) {
3046 			sfp->gpio_irq[i] = 0;
3047 			sfp->need_poll = true;
3048 		}
3049 	}
3050 
3051 	if (sfp->need_poll)
3052 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
3053 
3054 	/* We could have an issue in cases no Tx disable pin is available or
3055 	 * wired as modules using a laser as their light source will continue to
3056 	 * be active when the fiber is removed. This could be a safety issue and
3057 	 * we should at least warn the user about that.
3058 	 */
3059 	if (!sfp->gpio[GPIO_TX_DISABLE])
3060 		dev_warn(sfp->dev,
3061 			 "No tx_disable pin: SFP modules will always be emitting.\n");
3062 
3063 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
3064 	if (!sfp->sfp_bus)
3065 		return -ENOMEM;
3066 
3067 	sfp_debugfs_init(sfp);
3068 
3069 	return 0;
3070 }
3071 
3072 static int sfp_remove(struct platform_device *pdev)
3073 {
3074 	struct sfp *sfp = platform_get_drvdata(pdev);
3075 
3076 	sfp_debugfs_exit(sfp);
3077 	sfp_unregister_socket(sfp->sfp_bus);
3078 
3079 	rtnl_lock();
3080 	sfp_sm_event(sfp, SFP_E_REMOVE);
3081 	rtnl_unlock();
3082 
3083 	return 0;
3084 }
3085 
3086 static void sfp_shutdown(struct platform_device *pdev)
3087 {
3088 	struct sfp *sfp = platform_get_drvdata(pdev);
3089 	int i;
3090 
3091 	for (i = 0; i < GPIO_MAX; i++) {
3092 		if (!sfp->gpio_irq[i])
3093 			continue;
3094 
3095 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
3096 	}
3097 
3098 	cancel_delayed_work_sync(&sfp->poll);
3099 	cancel_delayed_work_sync(&sfp->timeout);
3100 }
3101 
3102 static struct platform_driver sfp_driver = {
3103 	.probe = sfp_probe,
3104 	.remove = sfp_remove,
3105 	.shutdown = sfp_shutdown,
3106 	.driver = {
3107 		.name = "sfp",
3108 		.of_match_table = sfp_of_match,
3109 	},
3110 };
3111 
3112 static int sfp_init(void)
3113 {
3114 	poll_jiffies = msecs_to_jiffies(100);
3115 
3116 	return platform_driver_register(&sfp_driver);
3117 }
3118 module_init(sfp_init);
3119 
3120 static void sfp_exit(void)
3121 {
3122 	platform_driver_unregister(&sfp_driver);
3123 }
3124 module_exit(sfp_exit);
3125 
3126 MODULE_ALIAS("platform:sfp");
3127 MODULE_AUTHOR("Russell King");
3128 MODULE_LICENSE("GPL v2");
3129