xref: /linux/drivers/net/phy/sfp.c (revision cf85f810f911234a06a4ef2439e8694b93b717fc)
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/unaligned.h>
18 #include <linux/workqueue.h>
19 
20 #include "sfp.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		25
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 /* Polling interval and consecutive-failure threshold for the I2C presence
211  * probe used on boards without a MOD_DEF0 GPIO (see sfp_i2c_get_state()).
212  * A single successful read asserts presence immediately; R_PROBE_ABSENT
213  * consecutive failures are required to declare a live module removed, to ride
214  * out a transient I2C error. Insertion is thus detected within
215  * T_PROBE_PRESENT and removal within T_PROBE_PRESENT * R_PROBE_ABSENT.
216  */
217 #define T_PROBE_PRESENT		msecs_to_jiffies(500)
218 #define R_PROBE_ABSENT		3
219 
220 /* SFP modules appear to always have their PHY configured for bus address
221  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
222  * RollBall SFPs access phy via SFP Enhanced Digital Diagnostic Interface
223  * via address 0x51 (mdio-i2c will use RollBall protocol on this address).
224  */
225 #define SFP_PHY_ADDR		22
226 #define SFP_PHY_ADDR_ROLLBALL	17
227 
228 /* SFP_EEPROM_BLOCK_SIZE is the size of data chunk to read the EEPROM
229  * at a time. Some SFP modules and also some Linux I2C drivers do not like
230  * reads longer than 16 bytes.
231  */
232 #define SFP_EEPROM_BLOCK_SIZE	16
233 
234 #define SFP_POLL_INTERVAL	msecs_to_jiffies(100)
235 
236 struct sff_data {
237 	unsigned int gpios;
238 	bool (*module_supported)(const struct sfp_eeprom_id *id);
239 };
240 
241 struct sfp {
242 	struct device *dev;
243 	struct i2c_adapter *i2c;
244 	struct mii_bus *i2c_mii;
245 	struct sfp_bus *sfp_bus;
246 	enum mdio_i2c_proto mdio_protocol;
247 	struct phy_device *mod_phy;
248 	const struct sff_data *type;
249 	size_t i2c_max_block_size;
250 	size_t i2c_block_size;
251 	u32 max_power_mW;
252 
253 	unsigned int (*get_state)(struct sfp *);
254 	void (*set_state)(struct sfp *, unsigned int);
255 	int (*read)(struct sfp *, bool, u8, void *, size_t);
256 	int (*write)(struct sfp *, bool, u8, void *, size_t);
257 
258 	struct gpio_desc *gpio[GPIO_MAX];
259 	int gpio_irq[GPIO_MAX];
260 
261 	bool need_poll;
262 
263 	/* I2C-probed presence, for boards without a MOD_DEF0 GPIO.
264 	 * Access rules: st_mutex held (updated from the poll/state machine).
265 	 */
266 	bool i2c_present;
267 	u8 i2c_present_nak;
268 	unsigned long i2c_present_next;
269 
270 	/* Access rules:
271 	 * state_hw_drive: st_mutex held
272 	 * state_hw_mask: st_mutex held
273 	 * state_soft_mask: st_mutex held
274 	 * state: st_mutex held unless reading input bits
275 	 */
276 	struct mutex st_mutex;			/* Protects state */
277 	unsigned int state_hw_drive;
278 	unsigned int state_hw_mask;
279 	unsigned int state_soft_mask;
280 	unsigned int state_ignore_mask;
281 	unsigned int state;
282 
283 	struct delayed_work poll;
284 	struct delayed_work timeout;
285 	struct mutex sm_mutex;			/* Protects state machine */
286 	unsigned char sm_mod_state;
287 	unsigned char sm_mod_tries_init;
288 	unsigned char sm_mod_tries;
289 	unsigned char sm_dev_state;
290 	unsigned short sm_state;
291 	unsigned char sm_fault_retries;
292 	unsigned char sm_phy_retries;
293 
294 	struct sfp_eeprom_id id;
295 	unsigned int module_power_mW;
296 	unsigned int module_t_start_up;
297 	unsigned int module_t_wait;
298 	unsigned int phy_t_retry;
299 
300 	unsigned int rate_kbd;
301 	unsigned int rs_threshold_kbd;
302 	unsigned int rs_state_mask;
303 
304 	bool have_a2;
305 
306 	const struct sfp_quirk *quirk;
307 
308 #if IS_ENABLED(CONFIG_HWMON)
309 	struct sfp_diag diag;
310 	struct delayed_work hwmon_probe;
311 	unsigned int hwmon_tries;
312 	struct device *hwmon_dev;
313 	char *hwmon_name;
314 #endif
315 
316 #if IS_ENABLED(CONFIG_DEBUG_FS)
317 	struct dentry *debugfs_dir;
318 #endif
319 };
320 
321 static void sfp_schedule_poll(struct sfp *sfp)
322 {
323 	mod_delayed_work(system_percpu_wq, &sfp->poll, SFP_POLL_INTERVAL);
324 }
325 
326 static bool sff_module_supported(const struct sfp_eeprom_id *id)
327 {
328 	return id->base.phys_id == SFF8024_ID_SFF_8472 &&
329 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
330 }
331 
332 static const struct sff_data sff_data = {
333 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
334 	.module_supported = sff_module_supported,
335 };
336 
337 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
338 {
339 	if (id->base.phys_id == SFF8024_ID_SFP &&
340 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP)
341 		return true;
342 
343 	/* SFP GPON module Ubiquiti U-Fiber Instant has in its EEPROM stored
344 	 * phys id SFF instead of SFP. Therefore mark this module explicitly
345 	 * as supported based on vendor name and pn match.
346 	 */
347 	if (id->base.phys_id == SFF8024_ID_SFF_8472 &&
348 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP &&
349 	    !memcmp(id->base.vendor_name, "UBNT            ", 16) &&
350 	    !memcmp(id->base.vendor_pn, "UF-INSTANT      ", 16))
351 		return true;
352 
353 	return false;
354 }
355 
356 static const struct sff_data sfp_data = {
357 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
358 		 SFP_F_TX_DISABLE | SFP_F_RS0 | SFP_F_RS1,
359 	.module_supported = sfp_module_supported,
360 };
361 
362 static const struct of_device_id sfp_of_match[] = {
363 	{ .compatible = "sff,sff", .data = &sff_data, },
364 	{ .compatible = "sff,sfp", .data = &sfp_data, },
365 	{ },
366 };
367 MODULE_DEVICE_TABLE(of, sfp_of_match);
368 
369 static void sfp_fixup_long_startup(struct sfp *sfp)
370 {
371 	sfp->module_t_start_up = T_START_UP_BAD_GPON;
372 }
373 
374 static void sfp_fixup_ignore_los(struct sfp *sfp)
375 {
376 	/* This forces LOS to zero, so we ignore transitions */
377 	sfp->state_ignore_mask |= SFP_F_LOS;
378 	/* Make sure that LOS options are clear */
379 	sfp->id.ext.options &= ~cpu_to_be16(SFP_OPTIONS_LOS_INVERTED |
380 					    SFP_OPTIONS_LOS_NORMAL);
381 }
382 
383 static void sfp_fixup_ignore_tx_fault(struct sfp *sfp)
384 {
385 	sfp->state_ignore_mask |= SFP_F_TX_FAULT;
386 }
387 
388 static void sfp_fixup_ignore_tx_fault_and_los(struct sfp *sfp)
389 {
390 	sfp_fixup_ignore_tx_fault(sfp);
391 	sfp_fixup_ignore_los(sfp);
392 }
393 
394 static void sfp_fixup_ignore_hw(struct sfp *sfp, unsigned int mask)
395 {
396 	sfp->state_hw_mask &= ~mask;
397 }
398 
399 static void sfp_fixup_nokia(struct sfp *sfp)
400 {
401 	sfp_fixup_long_startup(sfp);
402 	sfp_fixup_ignore_los(sfp);
403 }
404 
405 // For 10GBASE-T short-reach modules
406 static void sfp_fixup_10gbaset_30m(struct sfp *sfp)
407 {
408 	sfp->id.base.connector = SFF8024_CONNECTOR_RJ45;
409 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SR;
410 }
411 
412 static void sfp_fixup_rollball(struct sfp *sfp)
413 {
414 	sfp->mdio_protocol = MDIO_I2C_ROLLBALL;
415 
416 	/* RollBall modules may disallow access to PHY registers for up to 25
417 	 * seconds, and the reads return 0xffff before that. Increase the time
418 	 * between PHY probe retries from 50ms to 1s so that we will wait for
419 	 * the PHY for a sufficient amount of time.
420 	 */
421 	sfp->phy_t_retry = msecs_to_jiffies(1000);
422 }
423 
424 static void sfp_fixup_rollball_wait4s(struct sfp *sfp)
425 {
426 	sfp_fixup_rollball(sfp);
427 
428 	/* The RollBall fixup is not enough for FS modules, the PHY chip inside
429 	 * them does not return 0xffff for PHY ID registers in all MMDs for the
430 	 * while initializing. They need a 4 second wait before accessing PHY.
431 	 */
432 	sfp->module_t_wait = msecs_to_jiffies(4000);
433 }
434 
435 static void sfp_fixup_fs_10gt(struct sfp *sfp)
436 {
437 	sfp_fixup_10gbaset_30m(sfp);
438 	sfp_fixup_rollball_wait4s(sfp);
439 }
440 
441 static void sfp_fixup_halny_gsfp(struct sfp *sfp)
442 {
443 	/* Ignore the TX_FAULT and LOS signals on this module.
444 	 * these are possibly used for other purposes on this
445 	 * module, e.g. a serial port.
446 	 */
447 	sfp_fixup_ignore_hw(sfp, SFP_F_TX_FAULT | SFP_F_LOS);
448 }
449 
450 static void sfp_fixup_potron(struct sfp *sfp)
451 {
452 	/*
453 	 * The TX_FAULT and LOS pins on this device are used for serial
454 	 * communication, so ignore them. Additionally, provide extra
455 	 * time for this device to fully start up.
456 	 */
457 
458 	sfp_fixup_long_startup(sfp);
459 	sfp_fixup_ignore_hw(sfp, SFP_F_TX_FAULT | SFP_F_LOS);
460 }
461 
462 static void sfp_fixup_rollball_cc(struct sfp *sfp)
463 {
464 	sfp_fixup_rollball(sfp);
465 
466 	/* Some RollBall SFPs may have wrong (zero) extended compliance code
467 	 * burned in EEPROM. For PHY probing we need the correct one.
468 	 */
469 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SFI;
470 }
471 
472 static void sfp_quirk_2500basex(const struct sfp_eeprom_id *id,
473 				struct sfp_module_caps *caps)
474 {
475 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseX_Full_BIT,
476 			 caps->link_modes);
477 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, caps->interfaces);
478 }
479 
480 static void sfp_quirk_disable_autoneg(const struct sfp_eeprom_id *id,
481 				      struct sfp_module_caps *caps)
482 {
483 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, caps->link_modes);
484 }
485 
486 static void sfp_quirk_oem_2_5g(const struct sfp_eeprom_id *id,
487 			       struct sfp_module_caps *caps)
488 {
489 	/* Copper 2.5G SFP */
490 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
491 			 caps->link_modes);
492 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, caps->interfaces);
493 	sfp_quirk_disable_autoneg(id, caps);
494 }
495 
496 static void sfp_quirk_ubnt_uf_instant(const struct sfp_eeprom_id *id,
497 				      struct sfp_module_caps *caps)
498 {
499 	/* Ubiquiti U-Fiber Instant module claims that support all transceiver
500 	 * types including 10G Ethernet which is not truth. So clear all claimed
501 	 * modes and set only one mode which module supports: 1000baseX_Full,
502 	 * along with the Autoneg and pause bits.
503 	 */
504 	linkmode_zero(caps->link_modes);
505 	linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
506 			 caps->link_modes);
507 	linkmode_set_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, caps->link_modes);
508 	linkmode_set_bit(ETHTOOL_LINK_MODE_Pause_BIT, caps->link_modes);
509 	linkmode_set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, caps->link_modes);
510 
511 	phy_interface_zero(caps->interfaces);
512 	__set_bit(PHY_INTERFACE_MODE_1000BASEX, caps->interfaces);
513 }
514 
515 #define SFP_QUIRK(_v, _p, _s, _f) \
516 	{ .vendor = _v, .part = _p, .support = _s, .fixup = _f, }
517 #define SFP_QUIRK_S(_v, _p, _s) SFP_QUIRK(_v, _p, _s, NULL)
518 #define SFP_QUIRK_F(_v, _p, _f) SFP_QUIRK(_v, _p, NULL, _f)
519 
520 static const struct sfp_quirk sfp_quirks[] = {
521 	// Alcatel Lucent G-010S-P can operate at 2500base-X, but incorrectly
522 	// report 2500MBd NRZ in their EEPROM
523 	SFP_QUIRK("ALCATELLUCENT", "G010SP", sfp_quirk_2500basex,
524 		  sfp_fixup_ignore_tx_fault),
525 
526 	// Alcatel Lucent G-010S-A can operate at 2500base-X, but report 3.2GBd
527 	// NRZ in their EEPROM
528 	SFP_QUIRK("ALCATELLUCENT", "3FE46541AA", sfp_quirk_2500basex,
529 		  sfp_fixup_nokia),
530 
531 	SFP_QUIRK_F("BIDB", "X-ONU-SFPP", sfp_fixup_potron),
532 
533 	// FLYPRO SFP-10GT-CS-30M uses Rollball protocol to talk to the PHY.
534 	SFP_QUIRK_F("FLYPRO", "SFP-10GT-CS-30M", sfp_fixup_rollball),
535 
536 	// Fiberstore SFP-10G-T doesn't identify as copper, uses the Rollball
537 	// protocol to talk to the PHY and needs 4 sec wait before probing the
538 	// PHY.
539 	SFP_QUIRK_F("FS", "SFP-10G-T", sfp_fixup_fs_10gt),
540 
541 	// Fiberstore SFP-2.5G-T and SFP-10GM-T uses Rollball protocol to talk
542 	// to the PHY and needs 4 sec wait before probing the PHY.
543 	SFP_QUIRK_F("FS", "SFP-2.5G-T", sfp_fixup_rollball_wait4s),
544 	SFP_QUIRK_F("FS", "SFP-10GM-T", sfp_fixup_rollball_wait4s),
545 
546 	// Fiberstore GPON-ONU-34-20BI can operate at 2500base-X, but report 1.2GBd
547 	// NRZ in their EEPROM
548 	SFP_QUIRK("FS", "GPON-ONU-34-20BI", sfp_quirk_2500basex,
549 		  sfp_fixup_ignore_tx_fault),
550 
551 	SFP_QUIRK_F("HALNy", "HL-GSFP", sfp_fixup_halny_gsfp),
552 
553 	SFP_QUIRK_F("H-COM", "SPP425H-GAB4", sfp_fixup_potron),
554 
555 	// HG MXPD-483II-F 2.5G supports 2500Base-X, but incorrectly reports
556 	// 2600MBd in their EERPOM
557 	SFP_QUIRK_S("HG GENUINE", "MXPD-483II", sfp_quirk_2500basex),
558 
559 	// Huawei MA5671A can operate at 2500base-X, but report 1.2GBd NRZ in
560 	// their EEPROM
561 	SFP_QUIRK("HUAWEI", "MA5671A", sfp_quirk_2500basex,
562 		  sfp_fixup_ignore_tx_fault_and_los),
563 
564 	// Hisense LXT-010S-H is a GPON ONT SFP (sold as LEOX LXT-010S-H) that
565 	// can operate at 2500base-X, but reports 1000BASE-LX / 1300MBd in its
566 	// EEPROM
567 	SFP_QUIRK("Hisense-Leox", "LXT-010S-H", sfp_quirk_2500basex,
568 		  sfp_fixup_ignore_tx_fault),
569 
570 	// Hisense ZNID-GPON-2311NA can operate at 2500base-X, but reports
571 	// 1000BASE-LX / 1300MBd in its EEPROM
572 	SFP_QUIRK("Hisense", "ZNID-GPON-2311NA", sfp_quirk_2500basex,
573 		  sfp_fixup_ignore_tx_fault),
574 
575 	// HSGQ HSGQ-XPON-Stick can operate at 2500base-X, but reports
576 	// 1000BASE-LX / 1300MBd in its EEPROM
577 	SFP_QUIRK("HSGQ", "HSGQ-XPON-Stick", sfp_quirk_2500basex,
578 		  sfp_fixup_ignore_tx_fault),
579 
580 	// Lantech 8330-262D-E and 8330-265D can operate at 2500base-X, but
581 	// incorrectly report 2500MBd NRZ in their EEPROM.
582 	// Some 8330-265D modules have inverted LOS, while all of them report
583 	// normal LOS in EEPROM. Therefore we need to ignore LOS entirely.
584 	SFP_QUIRK_S("Lantech", "8330-262D-E", sfp_quirk_2500basex),
585 	SFP_QUIRK("Lantech", "8330-265D", sfp_quirk_2500basex,
586 		  sfp_fixup_ignore_los),
587 
588 	SFP_QUIRK_S("UBNT", "UF-INSTANT", sfp_quirk_ubnt_uf_instant),
589 
590 	// Walsun HXSX-ATR[CI]-1 don't identify as copper, and use the
591 	// Rollball protocol to talk to the PHY.
592 	SFP_QUIRK_F("Walsun", "HXSX-ATRC-1", sfp_fixup_fs_10gt),
593 	SFP_QUIRK_F("Walsun", "HXSX-ATRI-1", sfp_fixup_fs_10gt),
594 
595 	SFP_QUIRK_F("YV", "SFP+ONU-XGSPON", sfp_fixup_potron),
596 
597 	// HORACO HC-10GE-113C uses Rollball protocol to talk to the PHY.
598 	SFP_QUIRK_F("OEM", "HC-10GE-113C", sfp_fixup_rollball),
599 
600 	// OEM SFP-GE-T is a 1000Base-T module with broken TX_FAULT indicator
601 	SFP_QUIRK_F("OEM", "SFP-GE-T", sfp_fixup_ignore_tx_fault),
602 
603 	SFP_QUIRK_F("OEM", "SFP-10G-T", sfp_fixup_rollball_cc),
604 	SFP_QUIRK_S("OEM", "SFP-2.5G-T", sfp_quirk_oem_2_5g),
605 	SFP_QUIRK_S("OEM", "SFP-2.5G-BX10-D", sfp_quirk_2500basex),
606 	SFP_QUIRK_S("OEM", "SFP-2.5G-BX10-U", sfp_quirk_2500basex),
607 	SFP_QUIRK_S("OEM", "SFP-2.5G-LH03-B", sfp_quirk_2500basex),
608 	SFP_QUIRK_S("OEM", "SFP-2.5G-LH20-A", sfp_quirk_2500basex),
609 	SFP_QUIRK_F("OEM", "RTSFP-10", sfp_fixup_rollball_cc),
610 	SFP_QUIRK_F("OEM", "RTSFP-10G", sfp_fixup_rollball_cc),
611 	SFP_QUIRK_F("Turris", "RTSFP-2.5G", sfp_fixup_rollball),
612 	SFP_QUIRK_F("Turris", "RTSFP-10", sfp_fixup_rollball),
613 	SFP_QUIRK_F("Turris", "RTSFP-10G", sfp_fixup_rollball),
614 
615 	SFP_QUIRK_S("ZOERAX", "SFP-2.5G-T", sfp_quirk_oem_2_5g),
616 };
617 
618 static size_t sfp_strlen(const char *str, size_t maxlen)
619 {
620 	size_t size, i;
621 
622 	/* Trailing characters should be filled with space chars, but
623 	 * some manufacturers can't read SFF-8472 and use NUL.
624 	 */
625 	for (i = 0, size = 0; i < maxlen; i++)
626 		if (str[i] != ' ' && str[i] != '\0')
627 			size = i + 1;
628 
629 	return size;
630 }
631 
632 static bool sfp_match(const char *qs, const char *str, size_t len)
633 {
634 	if (!qs)
635 		return true;
636 	if (strlen(qs) != len)
637 		return false;
638 	return !strncmp(qs, str, len);
639 }
640 
641 static const struct sfp_quirk *sfp_lookup_quirk(const struct sfp_eeprom_id *id)
642 {
643 	const struct sfp_quirk *q;
644 	unsigned int i;
645 	size_t vs, ps;
646 
647 	vs = sfp_strlen(id->base.vendor_name, ARRAY_SIZE(id->base.vendor_name));
648 	ps = sfp_strlen(id->base.vendor_pn, ARRAY_SIZE(id->base.vendor_pn));
649 
650 	for (i = 0, q = sfp_quirks; i < ARRAY_SIZE(sfp_quirks); i++, q++)
651 		if (sfp_match(q->vendor, id->base.vendor_name, vs) &&
652 		    sfp_match(q->part, id->base.vendor_pn, ps))
653 			return q;
654 
655 	return NULL;
656 }
657 
658 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
659 {
660 	unsigned int i, state, v;
661 
662 	for (i = state = 0; i < GPIO_MAX; i++) {
663 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
664 			continue;
665 
666 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
667 		if (v)
668 			state |= BIT(i);
669 	}
670 
671 	return state;
672 }
673 
674 static unsigned int sff_gpio_get_state(struct sfp *sfp)
675 {
676 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
677 }
678 
679 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
680 {
681 	unsigned int drive;
682 
683 	if (state & SFP_F_PRESENT)
684 		/* If the module is present, drive the requested signals */
685 		drive = sfp->state_hw_drive;
686 	else
687 		/* Otherwise, let them float to the pull-ups */
688 		drive = 0;
689 
690 	if (sfp->gpio[GPIO_TX_DISABLE]) {
691 		if (drive & SFP_F_TX_DISABLE)
692 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
693 					       state & SFP_F_TX_DISABLE);
694 		else
695 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
696 	}
697 
698 	if (sfp->gpio[GPIO_RS0]) {
699 		if (drive & SFP_F_RS0)
700 			gpiod_direction_output(sfp->gpio[GPIO_RS0],
701 					       state & SFP_F_RS0);
702 		else
703 			gpiod_direction_input(sfp->gpio[GPIO_RS0]);
704 	}
705 
706 	if (sfp->gpio[GPIO_RS1]) {
707 		if (drive & SFP_F_RS1)
708 			gpiod_direction_output(sfp->gpio[GPIO_RS1],
709 					       state & SFP_F_RS1);
710 		else
711 			gpiod_direction_input(sfp->gpio[GPIO_RS1]);
712 	}
713 }
714 
715 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
716 			size_t len)
717 {
718 	struct i2c_msg msgs[2];
719 	u8 bus_addr = a2 ? 0x51 : 0x50;
720 	size_t block_size = sfp->i2c_block_size;
721 	size_t this_len;
722 	int ret;
723 
724 	msgs[0].addr = bus_addr;
725 	msgs[0].flags = 0;
726 	msgs[0].len = 1;
727 	msgs[0].buf = &dev_addr;
728 	msgs[1].addr = bus_addr;
729 	msgs[1].flags = I2C_M_RD;
730 	msgs[1].len = len;
731 	msgs[1].buf = buf;
732 
733 	while (len) {
734 		this_len = len;
735 		if (this_len > block_size)
736 			this_len = block_size;
737 
738 		msgs[1].len = this_len;
739 
740 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
741 		if (ret < 0)
742 			return ret;
743 
744 		if (ret != ARRAY_SIZE(msgs))
745 			break;
746 
747 		msgs[1].buf += this_len;
748 		dev_addr += this_len;
749 		len -= this_len;
750 	}
751 
752 	return msgs[1].buf - (u8 *)buf;
753 }
754 
755 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
756 	size_t len)
757 {
758 	struct i2c_msg msgs[1];
759 	u8 bus_addr = a2 ? 0x51 : 0x50;
760 	int ret;
761 
762 	msgs[0].addr = bus_addr;
763 	msgs[0].flags = 0;
764 	msgs[0].len = 1 + len;
765 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
766 	if (!msgs[0].buf)
767 		return -ENOMEM;
768 
769 	msgs[0].buf[0] = dev_addr;
770 	memcpy(&msgs[0].buf[1], buf, len);
771 
772 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
773 
774 	kfree(msgs[0].buf);
775 
776 	if (ret < 0)
777 		return ret;
778 
779 	return ret == ARRAY_SIZE(msgs) ? len : 0;
780 }
781 
782 static int sfp_smbus_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
783 			  size_t len)
784 {
785 	union i2c_smbus_data smbus_data = {0};
786 	u8 bus_addr = a2 ? 0x51 : 0x50;
787 	size_t this_len, transferred;
788 	u32 functionality;
789 	u8 *data = buf;
790 	int ret;
791 
792 	functionality = i2c_get_functionality(sfp->i2c);
793 
794 	while (len) {
795 		this_len = min(len, sfp->i2c_block_size);
796 
797 		if (functionality & I2C_FUNC_SMBUS_READ_I2C_BLOCK) {
798 			smbus_data.block[0] = this_len;
799 			ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
800 					     I2C_SMBUS_READ, dev_addr,
801 					     I2C_SMBUS_I2C_BLOCK_DATA, &smbus_data);
802 			if (ret < 0)
803 				return ret;
804 
805 			transferred = min_t(size_t, smbus_data.block[0], this_len);
806 			if (!transferred)
807 				return -EIO;
808 
809 			memcpy(data, &smbus_data.block[1], transferred);
810 		} else if (this_len >= 2 &&
811 			   (functionality & I2C_FUNC_SMBUS_READ_WORD_DATA)) {
812 			ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
813 					     I2C_SMBUS_READ, dev_addr,
814 					     I2C_SMBUS_WORD_DATA, &smbus_data);
815 			if (ret < 0)
816 				return ret;
817 
818 			put_unaligned_le16(smbus_data.word, data);
819 			transferred = 2;
820 		} else {
821 			ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
822 					     I2C_SMBUS_READ, dev_addr,
823 					     I2C_SMBUS_BYTE_DATA, &smbus_data);
824 			if (ret < 0)
825 				return ret;
826 
827 			*data = smbus_data.byte;
828 			transferred = 1;
829 		}
830 
831 		data += transferred;
832 		len -= transferred;
833 		dev_addr += transferred;
834 	}
835 
836 	return data - (u8 *)buf;
837 }
838 
839 static int sfp_smbus_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
840 			   size_t len)
841 {
842 	union i2c_smbus_data smbus_data;
843 	u8 bus_addr = a2 ? 0x51 : 0x50;
844 	size_t this_len, transferred;
845 	u32 functionality;
846 	u8 *data = buf;
847 	int ret;
848 
849 	functionality = i2c_get_functionality(sfp->i2c);
850 
851 	while (len) {
852 		this_len = min(len, sfp->i2c_block_size);
853 
854 		if (functionality & I2C_FUNC_SMBUS_WRITE_I2C_BLOCK) {
855 			smbus_data.block[0] = this_len;
856 			memcpy(&smbus_data.block[1], data, this_len);
857 
858 			ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
859 					     I2C_SMBUS_WRITE, dev_addr,
860 					     I2C_SMBUS_I2C_BLOCK_DATA, &smbus_data);
861 			if (ret < 0)
862 				return ret;
863 
864 			transferred = this_len;
865 		} else if (this_len >= 2 &&
866 			   (functionality & I2C_FUNC_SMBUS_WRITE_WORD_DATA)) {
867 			smbus_data.word = get_unaligned_le16(data);
868 			ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
869 					     I2C_SMBUS_WRITE, dev_addr,
870 					     I2C_SMBUS_WORD_DATA, &smbus_data);
871 			if (ret < 0)
872 				return ret;
873 
874 			transferred = 2;
875 		} else {
876 			smbus_data.byte = *data;
877 			ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
878 					     I2C_SMBUS_WRITE, dev_addr,
879 					     I2C_SMBUS_BYTE_DATA, &smbus_data);
880 			if (ret < 0)
881 				return ret;
882 
883 			transferred = 1;
884 		}
885 
886 		data += transferred;
887 		len -= transferred;
888 		dev_addr += transferred;
889 	}
890 
891 	return data - (u8 *)buf;
892 }
893 
894 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
895 {
896 	size_t max_block_size;
897 
898 	sfp->i2c = i2c;
899 
900 	if (i2c_check_functionality(i2c, I2C_FUNC_I2C)) {
901 		sfp->read = sfp_i2c_read;
902 		sfp->write = sfp_i2c_write;
903 		max_block_size = SFP_EEPROM_BLOCK_SIZE;
904 	} else if (i2c_check_functionality(i2c, I2C_FUNC_SMBUS_BYTE_DATA) ||
905 		   i2c_check_functionality(i2c, I2C_FUNC_SMBUS_I2C_BLOCK)) {
906 		/* Either protocol alone covers any length: I2C-block carries
907 		 * 1..32 bytes per xfer, byte iterates one byte at a time.
908 		 */
909 		sfp->read = sfp_smbus_read;
910 		sfp->write = sfp_smbus_write;
911 
912 		if (i2c_check_functionality(i2c, I2C_FUNC_SMBUS_I2C_BLOCK))
913 			max_block_size = SFP_EEPROM_BLOCK_SIZE;
914 		else if (i2c_check_functionality(i2c, I2C_FUNC_SMBUS_WORD_DATA))
915 			max_block_size = 2;
916 		else
917 			max_block_size = 1;
918 	} else if (WARN_ONCE(i2c_check_functionality(i2c, I2C_FUNC_SMBUS_WORD_DATA),
919 			     "SMBus word-only adapter; odd-length transfers will fail\n")) {
920 		/* Word-only: even-length xfers work; odd-length xfers fall
921 		 * to BYTE, which the adapter does not advertise and will
922 		 * likely fail.
923 		 */
924 		sfp->read = sfp_smbus_read;
925 		sfp->write = sfp_smbus_write;
926 		max_block_size = 2;
927 	} else {
928 		sfp->i2c = NULL;
929 		return -EINVAL;
930 	}
931 
932 	if (i2c->quirks && i2c->quirks->max_read_len)
933 		max_block_size = min(max_block_size, i2c->quirks->max_read_len);
934 	if (i2c->quirks && i2c->quirks->max_write_len)
935 		max_block_size = min(max_block_size, i2c->quirks->max_write_len);
936 
937 	sfp->i2c_max_block_size = max_block_size;
938 	sfp->i2c_block_size = sfp->i2c_max_block_size;
939 	return 0;
940 }
941 
942 static int sfp_i2c_mdiobus_create(struct sfp *sfp)
943 {
944 	struct mii_bus *i2c_mii;
945 	int ret;
946 
947 	i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, sfp->mdio_protocol);
948 	if (IS_ERR(i2c_mii))
949 		return PTR_ERR(i2c_mii);
950 
951 	i2c_mii->name = "SFP I2C Bus";
952 	i2c_mii->phy_mask = ~0;
953 
954 	ret = mdiobus_register(i2c_mii);
955 	if (ret < 0) {
956 		mdiobus_free(i2c_mii);
957 		return ret;
958 	}
959 
960 	sfp->i2c_mii = i2c_mii;
961 
962 	return 0;
963 }
964 
965 static void sfp_i2c_mdiobus_destroy(struct sfp *sfp)
966 {
967 	mdiobus_unregister(sfp->i2c_mii);
968 	mdiobus_free(sfp->i2c_mii);
969 	sfp->i2c_mii = NULL;
970 }
971 
972 /* Interface */
973 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
974 {
975 	return sfp->read(sfp, a2, addr, buf, len);
976 }
977 
978 /* Probe whether a module is physically present by attempting a single-byte
979  * I2C read of the EEPROM identifier (an empty cage NAKs). Used as the presence
980  * source on boards that do not wire MOD_DEF0 to a GPIO.
981  */
982 static bool sfp_module_present_i2c(struct sfp *sfp)
983 {
984 	u8 id;
985 
986 	return sfp_read(sfp, false, SFP_PHYS_ID, &id, sizeof(id)) == sizeof(id);
987 }
988 
989 /* get_state variant for boards without a MOD_DEF0 GPIO. Instead of assuming
990  * the module is always present, derive SFP_F_PRESENT from a throttled I2C
991  * probe so that hot-insertion and removal are detected. A single ACK asserts
992  * presence; R_PROBE_ABSENT consecutive failures clear it, to ride out a
993  * transient I2C error on a live module.
994  */
995 static unsigned int sfp_i2c_get_state(struct sfp *sfp)
996 {
997 	unsigned int state = sfp_gpio_get_state(sfp);
998 
999 	if (time_after_eq(jiffies, sfp->i2c_present_next)) {
1000 		if (sfp_module_present_i2c(sfp)) {
1001 			sfp->i2c_present = true;
1002 			sfp->i2c_present_nak = 0;
1003 		} else if (sfp->i2c_present &&
1004 			   ++sfp->i2c_present_nak >= R_PROBE_ABSENT) {
1005 			sfp->i2c_present = false;
1006 			sfp->i2c_present_nak = 0;
1007 		}
1008 		sfp->i2c_present_next = jiffies + T_PROBE_PRESENT;
1009 	}
1010 
1011 	if (sfp->i2c_present)
1012 		state |= SFP_F_PRESENT;
1013 
1014 	return state;
1015 }
1016 
1017 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
1018 {
1019 	return sfp->write(sfp, a2, addr, buf, len);
1020 }
1021 
1022 static int sfp_modify_u8(struct sfp *sfp, bool a2, u8 addr, u8 mask, u8 val)
1023 {
1024 	int ret;
1025 	u8 old, v;
1026 
1027 	ret = sfp_read(sfp, a2, addr, &old, sizeof(old));
1028 	if (ret != sizeof(old))
1029 		return ret;
1030 
1031 	v = (old & ~mask) | (val & mask);
1032 	if (v == old)
1033 		return sizeof(v);
1034 
1035 	return sfp_write(sfp, a2, addr, &v, sizeof(v));
1036 }
1037 
1038 static unsigned int sfp_soft_get_state(struct sfp *sfp)
1039 {
1040 	unsigned int state = 0;
1041 	u8 status;
1042 	int ret;
1043 
1044 	ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
1045 	if (ret == sizeof(status)) {
1046 		if (status & SFP_STATUS_RX_LOS)
1047 			state |= SFP_F_LOS;
1048 		if (status & SFP_STATUS_TX_FAULT)
1049 			state |= SFP_F_TX_FAULT;
1050 	} else {
1051 		dev_err_ratelimited(sfp->dev,
1052 				    "failed to read SFP soft status: %pe\n",
1053 				    ERR_PTR(ret));
1054 		/* Preserve the current state */
1055 		state = sfp->state;
1056 	}
1057 
1058 	return state & sfp->state_soft_mask;
1059 }
1060 
1061 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state,
1062 			       unsigned int soft)
1063 {
1064 	u8 mask = 0;
1065 	u8 val = 0;
1066 
1067 	if (soft & SFP_F_TX_DISABLE)
1068 		mask |= SFP_STATUS_TX_DISABLE_FORCE;
1069 	if (state & SFP_F_TX_DISABLE)
1070 		val |= SFP_STATUS_TX_DISABLE_FORCE;
1071 
1072 	if (soft & SFP_F_RS0)
1073 		mask |= SFP_STATUS_RS0_SELECT;
1074 	if (state & SFP_F_RS0)
1075 		val |= SFP_STATUS_RS0_SELECT;
1076 
1077 	if (mask)
1078 		sfp_modify_u8(sfp, true, SFP_STATUS, mask, val);
1079 
1080 	val = mask = 0;
1081 	if (soft & SFP_F_RS1)
1082 		mask |= SFP_EXT_STATUS_RS1_SELECT;
1083 	if (state & SFP_F_RS1)
1084 		val |= SFP_EXT_STATUS_RS1_SELECT;
1085 
1086 	if (mask)
1087 		sfp_modify_u8(sfp, true, SFP_EXT_STATUS, mask, val);
1088 }
1089 
1090 static void sfp_soft_start_poll(struct sfp *sfp)
1091 {
1092 	const struct sfp_eeprom_id *id = &sfp->id;
1093 	unsigned int mask = 0;
1094 
1095 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE)
1096 		mask |= SFP_F_TX_DISABLE;
1097 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT)
1098 		mask |= SFP_F_TX_FAULT;
1099 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS)
1100 		mask |= SFP_F_LOS;
1101 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RATE_SELECT)
1102 		mask |= sfp->rs_state_mask;
1103 
1104 	mutex_lock(&sfp->st_mutex);
1105 	// Poll the soft state for hardware pins we want to ignore
1106 	sfp->state_soft_mask = ~sfp->state_hw_mask & ~sfp->state_ignore_mask &
1107 			       mask;
1108 
1109 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
1110 	    !sfp->need_poll)
1111 		sfp_schedule_poll(sfp);
1112 	mutex_unlock(&sfp->st_mutex);
1113 }
1114 
1115 static void sfp_soft_stop_poll(struct sfp *sfp)
1116 {
1117 	mutex_lock(&sfp->st_mutex);
1118 	sfp->state_soft_mask = 0;
1119 	mutex_unlock(&sfp->st_mutex);
1120 }
1121 
1122 /* sfp_get_state() - must be called with st_mutex held, or in the
1123  * initialisation path.
1124  */
1125 static unsigned int sfp_get_state(struct sfp *sfp)
1126 {
1127 	unsigned int soft = sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT);
1128 	unsigned int state;
1129 
1130 	state = sfp->get_state(sfp) & sfp->state_hw_mask;
1131 	if (state & SFP_F_PRESENT && soft)
1132 		state |= sfp_soft_get_state(sfp);
1133 
1134 	return state;
1135 }
1136 
1137 /* sfp_set_state() - must be called with st_mutex held, or in the
1138  * initialisation path.
1139  */
1140 static void sfp_set_state(struct sfp *sfp, unsigned int state)
1141 {
1142 	unsigned int soft;
1143 
1144 	sfp->set_state(sfp, state);
1145 
1146 	soft = sfp->state_soft_mask & SFP_F_OUTPUTS;
1147 	if (state & SFP_F_PRESENT && soft)
1148 		sfp_soft_set_state(sfp, state, soft);
1149 }
1150 
1151 static void sfp_mod_state(struct sfp *sfp, unsigned int mask, unsigned int set)
1152 {
1153 	mutex_lock(&sfp->st_mutex);
1154 	sfp->state = (sfp->state & ~mask) | set;
1155 	sfp_set_state(sfp, sfp->state);
1156 	mutex_unlock(&sfp->st_mutex);
1157 }
1158 
1159 static unsigned int sfp_check(void *buf, size_t len)
1160 {
1161 	u8 *p, check;
1162 
1163 	for (p = buf, check = 0; len; p++, len--)
1164 		check += *p;
1165 
1166 	return check;
1167 }
1168 
1169 /* hwmon */
1170 #if IS_ENABLED(CONFIG_HWMON)
1171 static umode_t sfp_hwmon_is_visible(const void *data,
1172 				    enum hwmon_sensor_types type,
1173 				    u32 attr, int channel)
1174 {
1175 	const struct sfp *sfp = data;
1176 
1177 	switch (type) {
1178 	case hwmon_temp:
1179 		switch (attr) {
1180 		case hwmon_temp_min_alarm:
1181 		case hwmon_temp_max_alarm:
1182 		case hwmon_temp_lcrit_alarm:
1183 		case hwmon_temp_crit_alarm:
1184 		case hwmon_temp_min:
1185 		case hwmon_temp_max:
1186 		case hwmon_temp_lcrit:
1187 		case hwmon_temp_crit:
1188 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
1189 				return 0;
1190 			fallthrough;
1191 		case hwmon_temp_input:
1192 		case hwmon_temp_label:
1193 			return 0444;
1194 		default:
1195 			return 0;
1196 		}
1197 	case hwmon_in:
1198 		switch (attr) {
1199 		case hwmon_in_min_alarm:
1200 		case hwmon_in_max_alarm:
1201 		case hwmon_in_lcrit_alarm:
1202 		case hwmon_in_crit_alarm:
1203 		case hwmon_in_min:
1204 		case hwmon_in_max:
1205 		case hwmon_in_lcrit:
1206 		case hwmon_in_crit:
1207 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
1208 				return 0;
1209 			fallthrough;
1210 		case hwmon_in_input:
1211 		case hwmon_in_label:
1212 			return 0444;
1213 		default:
1214 			return 0;
1215 		}
1216 	case hwmon_curr:
1217 		switch (attr) {
1218 		case hwmon_curr_min_alarm:
1219 		case hwmon_curr_max_alarm:
1220 		case hwmon_curr_lcrit_alarm:
1221 		case hwmon_curr_crit_alarm:
1222 		case hwmon_curr_min:
1223 		case hwmon_curr_max:
1224 		case hwmon_curr_lcrit:
1225 		case hwmon_curr_crit:
1226 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
1227 				return 0;
1228 			fallthrough;
1229 		case hwmon_curr_input:
1230 		case hwmon_curr_label:
1231 			return 0444;
1232 		default:
1233 			return 0;
1234 		}
1235 	case hwmon_power:
1236 		/* External calibration of receive power requires
1237 		 * floating point arithmetic. Doing that in the kernel
1238 		 * is not easy, so just skip it. If the module does
1239 		 * not require external calibration, we can however
1240 		 * show receiver power, since FP is then not needed.
1241 		 */
1242 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
1243 		    channel == 1)
1244 			return 0;
1245 		switch (attr) {
1246 		case hwmon_power_min_alarm:
1247 		case hwmon_power_max_alarm:
1248 		case hwmon_power_lcrit_alarm:
1249 		case hwmon_power_crit_alarm:
1250 		case hwmon_power_min:
1251 		case hwmon_power_max:
1252 		case hwmon_power_lcrit:
1253 		case hwmon_power_crit:
1254 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
1255 				return 0;
1256 			fallthrough;
1257 		case hwmon_power_input:
1258 		case hwmon_power_label:
1259 			return 0444;
1260 		default:
1261 			return 0;
1262 		}
1263 	default:
1264 		return 0;
1265 	}
1266 }
1267 
1268 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
1269 {
1270 	__be16 val;
1271 	int err;
1272 
1273 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
1274 	if (err < 0)
1275 		return err;
1276 
1277 	*value = be16_to_cpu(val);
1278 
1279 	return 0;
1280 }
1281 
1282 static void sfp_hwmon_to_rx_power(long *value)
1283 {
1284 	*value = DIV_ROUND_CLOSEST(*value, 10);
1285 }
1286 
1287 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
1288 				long *value)
1289 {
1290 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
1291 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
1292 }
1293 
1294 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
1295 {
1296 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
1297 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
1298 
1299 	if (*value >= 0x8000)
1300 		*value -= 0x10000;
1301 
1302 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
1303 }
1304 
1305 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
1306 {
1307 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
1308 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
1309 
1310 	*value = DIV_ROUND_CLOSEST(*value, 10);
1311 }
1312 
1313 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
1314 {
1315 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
1316 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
1317 
1318 	*value = DIV_ROUND_CLOSEST(*value, 500);
1319 }
1320 
1321 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
1322 {
1323 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
1324 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
1325 
1326 	*value = DIV_ROUND_CLOSEST(*value, 10);
1327 }
1328 
1329 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
1330 {
1331 	int err;
1332 
1333 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1334 	if (err < 0)
1335 		return err;
1336 
1337 	sfp_hwmon_calibrate_temp(sfp, value);
1338 
1339 	return 0;
1340 }
1341 
1342 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
1343 {
1344 	int err;
1345 
1346 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1347 	if (err < 0)
1348 		return err;
1349 
1350 	sfp_hwmon_calibrate_vcc(sfp, value);
1351 
1352 	return 0;
1353 }
1354 
1355 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
1356 {
1357 	int err;
1358 
1359 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1360 	if (err < 0)
1361 		return err;
1362 
1363 	sfp_hwmon_calibrate_bias(sfp, value);
1364 
1365 	return 0;
1366 }
1367 
1368 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
1369 {
1370 	int err;
1371 
1372 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1373 	if (err < 0)
1374 		return err;
1375 
1376 	sfp_hwmon_calibrate_tx_power(sfp, value);
1377 
1378 	return 0;
1379 }
1380 
1381 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
1382 {
1383 	int err;
1384 
1385 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1386 	if (err < 0)
1387 		return err;
1388 
1389 	sfp_hwmon_to_rx_power(value);
1390 
1391 	return 0;
1392 }
1393 
1394 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
1395 {
1396 	u8 status;
1397 	int err;
1398 
1399 	switch (attr) {
1400 	case hwmon_temp_input:
1401 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
1402 
1403 	case hwmon_temp_lcrit:
1404 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
1405 		sfp_hwmon_calibrate_temp(sfp, value);
1406 		return 0;
1407 
1408 	case hwmon_temp_min:
1409 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
1410 		sfp_hwmon_calibrate_temp(sfp, value);
1411 		return 0;
1412 	case hwmon_temp_max:
1413 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
1414 		sfp_hwmon_calibrate_temp(sfp, value);
1415 		return 0;
1416 
1417 	case hwmon_temp_crit:
1418 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
1419 		sfp_hwmon_calibrate_temp(sfp, value);
1420 		return 0;
1421 
1422 	case hwmon_temp_lcrit_alarm:
1423 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1424 		if (err < 0)
1425 			return err;
1426 
1427 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
1428 		return 0;
1429 
1430 	case hwmon_temp_min_alarm:
1431 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1432 		if (err < 0)
1433 			return err;
1434 
1435 		*value = !!(status & SFP_WARN0_TEMP_LOW);
1436 		return 0;
1437 
1438 	case hwmon_temp_max_alarm:
1439 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1440 		if (err < 0)
1441 			return err;
1442 
1443 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
1444 		return 0;
1445 
1446 	case hwmon_temp_crit_alarm:
1447 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1448 		if (err < 0)
1449 			return err;
1450 
1451 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
1452 		return 0;
1453 	default:
1454 		return -EOPNOTSUPP;
1455 	}
1456 
1457 	return -EOPNOTSUPP;
1458 }
1459 
1460 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
1461 {
1462 	u8 status;
1463 	int err;
1464 
1465 	switch (attr) {
1466 	case hwmon_in_input:
1467 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
1468 
1469 	case hwmon_in_lcrit:
1470 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
1471 		sfp_hwmon_calibrate_vcc(sfp, value);
1472 		return 0;
1473 
1474 	case hwmon_in_min:
1475 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
1476 		sfp_hwmon_calibrate_vcc(sfp, value);
1477 		return 0;
1478 
1479 	case hwmon_in_max:
1480 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
1481 		sfp_hwmon_calibrate_vcc(sfp, value);
1482 		return 0;
1483 
1484 	case hwmon_in_crit:
1485 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
1486 		sfp_hwmon_calibrate_vcc(sfp, value);
1487 		return 0;
1488 
1489 	case hwmon_in_lcrit_alarm:
1490 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1491 		if (err < 0)
1492 			return err;
1493 
1494 		*value = !!(status & SFP_ALARM0_VCC_LOW);
1495 		return 0;
1496 
1497 	case hwmon_in_min_alarm:
1498 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1499 		if (err < 0)
1500 			return err;
1501 
1502 		*value = !!(status & SFP_WARN0_VCC_LOW);
1503 		return 0;
1504 
1505 	case hwmon_in_max_alarm:
1506 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1507 		if (err < 0)
1508 			return err;
1509 
1510 		*value = !!(status & SFP_WARN0_VCC_HIGH);
1511 		return 0;
1512 
1513 	case hwmon_in_crit_alarm:
1514 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1515 		if (err < 0)
1516 			return err;
1517 
1518 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
1519 		return 0;
1520 	default:
1521 		return -EOPNOTSUPP;
1522 	}
1523 
1524 	return -EOPNOTSUPP;
1525 }
1526 
1527 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
1528 {
1529 	u8 status;
1530 	int err;
1531 
1532 	switch (attr) {
1533 	case hwmon_curr_input:
1534 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
1535 
1536 	case hwmon_curr_lcrit:
1537 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
1538 		sfp_hwmon_calibrate_bias(sfp, value);
1539 		return 0;
1540 
1541 	case hwmon_curr_min:
1542 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
1543 		sfp_hwmon_calibrate_bias(sfp, value);
1544 		return 0;
1545 
1546 	case hwmon_curr_max:
1547 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
1548 		sfp_hwmon_calibrate_bias(sfp, value);
1549 		return 0;
1550 
1551 	case hwmon_curr_crit:
1552 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
1553 		sfp_hwmon_calibrate_bias(sfp, value);
1554 		return 0;
1555 
1556 	case hwmon_curr_lcrit_alarm:
1557 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1558 		if (err < 0)
1559 			return err;
1560 
1561 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
1562 		return 0;
1563 
1564 	case hwmon_curr_min_alarm:
1565 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1566 		if (err < 0)
1567 			return err;
1568 
1569 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
1570 		return 0;
1571 
1572 	case hwmon_curr_max_alarm:
1573 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1574 		if (err < 0)
1575 			return err;
1576 
1577 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
1578 		return 0;
1579 
1580 	case hwmon_curr_crit_alarm:
1581 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1582 		if (err < 0)
1583 			return err;
1584 
1585 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
1586 		return 0;
1587 	default:
1588 		return -EOPNOTSUPP;
1589 	}
1590 
1591 	return -EOPNOTSUPP;
1592 }
1593 
1594 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
1595 {
1596 	u8 status;
1597 	int err;
1598 
1599 	switch (attr) {
1600 	case hwmon_power_input:
1601 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
1602 
1603 	case hwmon_power_lcrit:
1604 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
1605 		sfp_hwmon_calibrate_tx_power(sfp, value);
1606 		return 0;
1607 
1608 	case hwmon_power_min:
1609 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
1610 		sfp_hwmon_calibrate_tx_power(sfp, value);
1611 		return 0;
1612 
1613 	case hwmon_power_max:
1614 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
1615 		sfp_hwmon_calibrate_tx_power(sfp, value);
1616 		return 0;
1617 
1618 	case hwmon_power_crit:
1619 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
1620 		sfp_hwmon_calibrate_tx_power(sfp, value);
1621 		return 0;
1622 
1623 	case hwmon_power_lcrit_alarm:
1624 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1625 		if (err < 0)
1626 			return err;
1627 
1628 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
1629 		return 0;
1630 
1631 	case hwmon_power_min_alarm:
1632 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1633 		if (err < 0)
1634 			return err;
1635 
1636 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
1637 		return 0;
1638 
1639 	case hwmon_power_max_alarm:
1640 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1641 		if (err < 0)
1642 			return err;
1643 
1644 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1645 		return 0;
1646 
1647 	case hwmon_power_crit_alarm:
1648 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1649 		if (err < 0)
1650 			return err;
1651 
1652 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1653 		return 0;
1654 	default:
1655 		return -EOPNOTSUPP;
1656 	}
1657 
1658 	return -EOPNOTSUPP;
1659 }
1660 
1661 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1662 {
1663 	u8 status;
1664 	int err;
1665 
1666 	switch (attr) {
1667 	case hwmon_power_input:
1668 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1669 
1670 	case hwmon_power_lcrit:
1671 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1672 		sfp_hwmon_to_rx_power(value);
1673 		return 0;
1674 
1675 	case hwmon_power_min:
1676 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1677 		sfp_hwmon_to_rx_power(value);
1678 		return 0;
1679 
1680 	case hwmon_power_max:
1681 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1682 		sfp_hwmon_to_rx_power(value);
1683 		return 0;
1684 
1685 	case hwmon_power_crit:
1686 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1687 		sfp_hwmon_to_rx_power(value);
1688 		return 0;
1689 
1690 	case hwmon_power_lcrit_alarm:
1691 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1692 		if (err < 0)
1693 			return err;
1694 
1695 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1696 		return 0;
1697 
1698 	case hwmon_power_min_alarm:
1699 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1700 		if (err < 0)
1701 			return err;
1702 
1703 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1704 		return 0;
1705 
1706 	case hwmon_power_max_alarm:
1707 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1708 		if (err < 0)
1709 			return err;
1710 
1711 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1712 		return 0;
1713 
1714 	case hwmon_power_crit_alarm:
1715 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1716 		if (err < 0)
1717 			return err;
1718 
1719 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1720 		return 0;
1721 	default:
1722 		return -EOPNOTSUPP;
1723 	}
1724 
1725 	return -EOPNOTSUPP;
1726 }
1727 
1728 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1729 			  u32 attr, int channel, long *value)
1730 {
1731 	struct sfp *sfp = dev_get_drvdata(dev);
1732 
1733 	switch (type) {
1734 	case hwmon_temp:
1735 		return sfp_hwmon_temp(sfp, attr, value);
1736 	case hwmon_in:
1737 		return sfp_hwmon_vcc(sfp, attr, value);
1738 	case hwmon_curr:
1739 		return sfp_hwmon_bias(sfp, attr, value);
1740 	case hwmon_power:
1741 		switch (channel) {
1742 		case 0:
1743 			return sfp_hwmon_tx_power(sfp, attr, value);
1744 		case 1:
1745 			return sfp_hwmon_rx_power(sfp, attr, value);
1746 		default:
1747 			return -EOPNOTSUPP;
1748 		}
1749 	default:
1750 		return -EOPNOTSUPP;
1751 	}
1752 }
1753 
1754 static const char *const sfp_hwmon_power_labels[] = {
1755 	"TX_power",
1756 	"RX_power",
1757 };
1758 
1759 static int sfp_hwmon_read_string(struct device *dev,
1760 				 enum hwmon_sensor_types type,
1761 				 u32 attr, int channel, const char **str)
1762 {
1763 	switch (type) {
1764 	case hwmon_curr:
1765 		switch (attr) {
1766 		case hwmon_curr_label:
1767 			*str = "bias";
1768 			return 0;
1769 		default:
1770 			return -EOPNOTSUPP;
1771 		}
1772 		break;
1773 	case hwmon_temp:
1774 		switch (attr) {
1775 		case hwmon_temp_label:
1776 			*str = "temperature";
1777 			return 0;
1778 		default:
1779 			return -EOPNOTSUPP;
1780 		}
1781 		break;
1782 	case hwmon_in:
1783 		switch (attr) {
1784 		case hwmon_in_label:
1785 			*str = "VCC";
1786 			return 0;
1787 		default:
1788 			return -EOPNOTSUPP;
1789 		}
1790 		break;
1791 	case hwmon_power:
1792 		switch (attr) {
1793 		case hwmon_power_label:
1794 			*str = sfp_hwmon_power_labels[channel];
1795 			return 0;
1796 		default:
1797 			return -EOPNOTSUPP;
1798 		}
1799 		break;
1800 	default:
1801 		return -EOPNOTSUPP;
1802 	}
1803 
1804 	return -EOPNOTSUPP;
1805 }
1806 
1807 static const struct hwmon_ops sfp_hwmon_ops = {
1808 	.is_visible = sfp_hwmon_is_visible,
1809 	.read = sfp_hwmon_read,
1810 	.read_string = sfp_hwmon_read_string,
1811 };
1812 
1813 static const struct hwmon_channel_info * const sfp_hwmon_info[] = {
1814 	HWMON_CHANNEL_INFO(chip,
1815 			   HWMON_C_REGISTER_TZ),
1816 	HWMON_CHANNEL_INFO(in,
1817 			   HWMON_I_INPUT |
1818 			   HWMON_I_MAX | HWMON_I_MIN |
1819 			   HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1820 			   HWMON_I_CRIT | HWMON_I_LCRIT |
1821 			   HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1822 			   HWMON_I_LABEL),
1823 	HWMON_CHANNEL_INFO(temp,
1824 			   HWMON_T_INPUT |
1825 			   HWMON_T_MAX | HWMON_T_MIN |
1826 			   HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1827 			   HWMON_T_CRIT | HWMON_T_LCRIT |
1828 			   HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1829 			   HWMON_T_LABEL),
1830 	HWMON_CHANNEL_INFO(curr,
1831 			   HWMON_C_INPUT |
1832 			   HWMON_C_MAX | HWMON_C_MIN |
1833 			   HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1834 			   HWMON_C_CRIT | HWMON_C_LCRIT |
1835 			   HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1836 			   HWMON_C_LABEL),
1837 	HWMON_CHANNEL_INFO(power,
1838 			   /* Transmit power */
1839 			   HWMON_P_INPUT |
1840 			   HWMON_P_MAX | HWMON_P_MIN |
1841 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1842 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1843 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1844 			   HWMON_P_LABEL,
1845 			   /* Receive power */
1846 			   HWMON_P_INPUT |
1847 			   HWMON_P_MAX | HWMON_P_MIN |
1848 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1849 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1850 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1851 			   HWMON_P_LABEL),
1852 	NULL,
1853 };
1854 
1855 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1856 	.ops = &sfp_hwmon_ops,
1857 	.info = sfp_hwmon_info,
1858 };
1859 
1860 static void sfp_hwmon_probe(struct work_struct *work)
1861 {
1862 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1863 	int err;
1864 
1865 	/* hwmon interface needs to access 16bit registers in atomic way to
1866 	 * guarantee coherency of the diagnostic monitoring data. If it is not
1867 	 * possible to guarantee coherency because EEPROM is broken in such way
1868 	 * that does not support atomic 16bit read operation then we have to
1869 	 * skip registration of hwmon device.
1870 	 */
1871 	if (sfp->i2c_block_size < 2) {
1872 		dev_info(sfp->dev,
1873 			 "skipping hwmon device registration\n");
1874 		dev_info(sfp->dev,
1875 			 "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
1876 		return;
1877 	}
1878 
1879 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1880 	if (err < 0) {
1881 		if (sfp->hwmon_tries--) {
1882 			mod_delayed_work(system_percpu_wq, &sfp->hwmon_probe,
1883 					 T_PROBE_RETRY_SLOW);
1884 		} else {
1885 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
1886 				 ERR_PTR(err));
1887 		}
1888 		return;
1889 	}
1890 
1891 	sfp->hwmon_name = hwmon_sanitize_name(dev_name(sfp->dev));
1892 	if (IS_ERR(sfp->hwmon_name)) {
1893 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1894 		return;
1895 	}
1896 
1897 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1898 							 sfp->hwmon_name, sfp,
1899 							 &sfp_hwmon_chip_info,
1900 							 NULL);
1901 	if (IS_ERR(sfp->hwmon_dev))
1902 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1903 			PTR_ERR(sfp->hwmon_dev));
1904 }
1905 
1906 static int sfp_hwmon_insert(struct sfp *sfp)
1907 {
1908 	if (sfp->have_a2 && sfp->id.ext.diagmon & SFP_DIAGMON_DDM) {
1909 		mod_delayed_work(system_percpu_wq, &sfp->hwmon_probe, 1);
1910 		sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1911 	}
1912 
1913 	return 0;
1914 }
1915 
1916 static void sfp_hwmon_remove(struct sfp *sfp)
1917 {
1918 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1919 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1920 		hwmon_device_unregister(sfp->hwmon_dev);
1921 		sfp->hwmon_dev = NULL;
1922 	}
1923 
1924 	if (!IS_ERR_OR_NULL(sfp->hwmon_name)) {
1925 		kfree(sfp->hwmon_name);
1926 		sfp->hwmon_name = NULL;
1927 	}
1928 }
1929 
1930 static int sfp_hwmon_init(struct sfp *sfp)
1931 {
1932 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1933 
1934 	return 0;
1935 }
1936 
1937 static void sfp_hwmon_exit(struct sfp *sfp)
1938 {
1939 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1940 }
1941 #else
1942 static int sfp_hwmon_insert(struct sfp *sfp)
1943 {
1944 	return 0;
1945 }
1946 
1947 static void sfp_hwmon_remove(struct sfp *sfp)
1948 {
1949 }
1950 
1951 static int sfp_hwmon_init(struct sfp *sfp)
1952 {
1953 	return 0;
1954 }
1955 
1956 static void sfp_hwmon_exit(struct sfp *sfp)
1957 {
1958 }
1959 #endif
1960 
1961 /* Helpers */
1962 static void sfp_module_tx_disable(struct sfp *sfp)
1963 {
1964 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1965 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1966 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, SFP_F_TX_DISABLE);
1967 }
1968 
1969 static void sfp_module_tx_enable(struct sfp *sfp)
1970 {
1971 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1972 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1973 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, 0);
1974 }
1975 
1976 #if IS_ENABLED(CONFIG_DEBUG_FS)
1977 static int sfp_debug_state_show(struct seq_file *s, void *data)
1978 {
1979 	struct sfp *sfp = s->private;
1980 
1981 	seq_printf(s, "Module state: %s\n",
1982 		   mod_state_to_str(sfp->sm_mod_state));
1983 	seq_printf(s, "Module probe attempts: %d %d\n",
1984 		   R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
1985 		   R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
1986 	seq_printf(s, "Device state: %s\n",
1987 		   dev_state_to_str(sfp->sm_dev_state));
1988 	seq_printf(s, "Main state: %s\n",
1989 		   sm_state_to_str(sfp->sm_state));
1990 	seq_printf(s, "Fault recovery remaining retries: %d\n",
1991 		   sfp->sm_fault_retries);
1992 	seq_printf(s, "PHY probe remaining retries: %d\n",
1993 		   sfp->sm_phy_retries);
1994 	seq_printf(s, "Signalling rate: %u kBd\n", sfp->rate_kbd);
1995 	seq_printf(s, "Rate select threshold: %u kBd\n",
1996 		   sfp->rs_threshold_kbd);
1997 	seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
1998 	seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
1999 	seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
2000 	seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
2001 	seq_printf(s, "rs0: %d\n", !!(sfp->state & SFP_F_RS0));
2002 	seq_printf(s, "rs1: %d\n", !!(sfp->state & SFP_F_RS1));
2003 	return 0;
2004 }
2005 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
2006 
2007 static void sfp_debugfs_init(struct sfp *sfp)
2008 {
2009 	sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
2010 
2011 	debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
2012 			    &sfp_debug_state_fops);
2013 }
2014 
2015 static void sfp_debugfs_exit(struct sfp *sfp)
2016 {
2017 	debugfs_remove_recursive(sfp->debugfs_dir);
2018 }
2019 #else
2020 static void sfp_debugfs_init(struct sfp *sfp)
2021 {
2022 }
2023 
2024 static void sfp_debugfs_exit(struct sfp *sfp)
2025 {
2026 }
2027 #endif
2028 
2029 static void sfp_module_tx_fault_reset(struct sfp *sfp)
2030 {
2031 	unsigned int state;
2032 
2033 	mutex_lock(&sfp->st_mutex);
2034 	state = sfp->state;
2035 	if (!(state & SFP_F_TX_DISABLE)) {
2036 		sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
2037 
2038 		udelay(T_RESET_US);
2039 
2040 		sfp_set_state(sfp, state);
2041 	}
2042 	mutex_unlock(&sfp->st_mutex);
2043 }
2044 
2045 /* SFP state machine */
2046 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
2047 {
2048 	if (timeout)
2049 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
2050 				 timeout);
2051 	else
2052 		cancel_delayed_work(&sfp->timeout);
2053 }
2054 
2055 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
2056 			unsigned int timeout)
2057 {
2058 	sfp->sm_state = state;
2059 	sfp_sm_set_timer(sfp, timeout);
2060 }
2061 
2062 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
2063 			    unsigned int timeout)
2064 {
2065 	sfp->sm_mod_state = state;
2066 	sfp_sm_set_timer(sfp, timeout);
2067 }
2068 
2069 static void sfp_sm_phy_detach(struct sfp *sfp)
2070 {
2071 	sfp_remove_phy(sfp->sfp_bus);
2072 	phy_device_remove(sfp->mod_phy);
2073 	phy_device_free(sfp->mod_phy);
2074 	sfp->mod_phy = NULL;
2075 }
2076 
2077 static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
2078 {
2079 	struct phy_device *phy;
2080 	int err;
2081 
2082 	phy = get_phy_device(sfp->i2c_mii, addr, is_c45);
2083 	if (phy == ERR_PTR(-ENODEV))
2084 		return PTR_ERR(phy);
2085 	if (IS_ERR(phy)) {
2086 		dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
2087 		return PTR_ERR(phy);
2088 	}
2089 
2090 	/* Mark this PHY as being on a SFP module */
2091 	phy->is_on_sfp_module = true;
2092 
2093 	err = phy_device_register(phy);
2094 	if (err) {
2095 		phy_device_free(phy);
2096 		dev_err(sfp->dev, "phy_device_register failed: %pe\n",
2097 			ERR_PTR(err));
2098 		return err;
2099 	}
2100 
2101 	err = sfp_add_phy(sfp->sfp_bus, phy);
2102 	if (err) {
2103 		phy_device_remove(phy);
2104 		phy_device_free(phy);
2105 		dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
2106 		return err;
2107 	}
2108 
2109 	sfp->mod_phy = phy;
2110 
2111 	return 0;
2112 }
2113 
2114 static void sfp_sm_link_up(struct sfp *sfp)
2115 {
2116 	sfp_link_up(sfp->sfp_bus);
2117 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
2118 }
2119 
2120 static void sfp_sm_link_down(struct sfp *sfp)
2121 {
2122 	sfp_link_down(sfp->sfp_bus);
2123 }
2124 
2125 static void sfp_sm_link_check_los(struct sfp *sfp)
2126 {
2127 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
2128 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
2129 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
2130 	bool los = false;
2131 
2132 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
2133 	 * are set, we assume that no LOS signal is available. If both are
2134 	 * set, we assume LOS is not implemented (and is meaningless.)
2135 	 */
2136 	if (los_options == los_inverted)
2137 		los = !(sfp->state & SFP_F_LOS);
2138 	else if (los_options == los_normal)
2139 		los = !!(sfp->state & SFP_F_LOS);
2140 
2141 	if (los)
2142 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2143 	else
2144 		sfp_sm_link_up(sfp);
2145 }
2146 
2147 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
2148 {
2149 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
2150 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
2151 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
2152 
2153 	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
2154 	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
2155 }
2156 
2157 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
2158 {
2159 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
2160 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
2161 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
2162 
2163 	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
2164 	       (los_options == los_normal && event == SFP_E_LOS_LOW);
2165 }
2166 
2167 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
2168 {
2169 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
2170 		dev_err(sfp->dev,
2171 			"module persistently indicates fault, disabling\n");
2172 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
2173 	} else {
2174 		if (warn)
2175 			dev_err(sfp->dev, "module transmit fault indicated\n");
2176 
2177 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
2178 	}
2179 }
2180 
2181 static int sfp_sm_add_mdio_bus(struct sfp *sfp)
2182 {
2183 	if (sfp->mdio_protocol != MDIO_I2C_NONE)
2184 		return sfp_i2c_mdiobus_create(sfp);
2185 
2186 	return 0;
2187 }
2188 
2189 /* Probe a SFP for a PHY device if the module supports copper - the PHY
2190  * normally sits at I2C bus address 0x56, and may either be a clause 22
2191  * or clause 45 PHY.
2192  *
2193  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
2194  * negotiation enabled, but some may be in 1000base-X - which is for the
2195  * PHY driver to determine.
2196  *
2197  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
2198  * mode according to the negotiated line speed.
2199  */
2200 static int sfp_sm_probe_for_phy(struct sfp *sfp)
2201 {
2202 	int err = 0;
2203 
2204 	switch (sfp->mdio_protocol) {
2205 	case MDIO_I2C_NONE:
2206 		break;
2207 
2208 	case MDIO_I2C_MARVELL_C22:
2209 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, false);
2210 		break;
2211 
2212 	case MDIO_I2C_C45:
2213 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, true);
2214 		break;
2215 
2216 	case MDIO_I2C_ROLLBALL:
2217 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR_ROLLBALL, true);
2218 		break;
2219 	}
2220 
2221 	return err;
2222 }
2223 
2224 static int sfp_module_parse_power(struct sfp *sfp)
2225 {
2226 	u32 power_mW = 1000;
2227 	bool supports_a2;
2228 
2229 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
2230 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
2231 		power_mW = 1500;
2232 	/* Added in Rev 11.9, but there is no compliance code for this */
2233 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV11_4 &&
2234 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
2235 		power_mW = 2000;
2236 
2237 	/* Power level 1 modules (max. 1W) are always supported. */
2238 	if (power_mW <= 1000) {
2239 		sfp->module_power_mW = power_mW;
2240 		return 0;
2241 	}
2242 
2243 	supports_a2 = sfp->id.ext.sff8472_compliance !=
2244 				SFP_SFF8472_COMPLIANCE_NONE ||
2245 		      sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
2246 
2247 	if (power_mW > sfp->max_power_mW) {
2248 		/* Module power specification exceeds the allowed maximum. */
2249 		if (!supports_a2) {
2250 			/* The module appears not to implement bus address
2251 			 * 0xa2, so assume that the module powers up in the
2252 			 * indicated mode.
2253 			 */
2254 			dev_err(sfp->dev,
2255 				"Host does not support %u.%uW modules\n",
2256 				power_mW / 1000, (power_mW / 100) % 10);
2257 			return -EINVAL;
2258 		} else {
2259 			dev_warn(sfp->dev,
2260 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
2261 				 power_mW / 1000, (power_mW / 100) % 10);
2262 			return 0;
2263 		}
2264 	}
2265 
2266 	if (!supports_a2) {
2267 		/* The module power level is below the host maximum and the
2268 		 * module appears not to implement bus address 0xa2, so assume
2269 		 * that the module powers up in the indicated mode.
2270 		 */
2271 		return 0;
2272 	}
2273 
2274 	/* If the module requires a higher power mode, but also requires
2275 	 * an address change sequence, warn the user that the module may
2276 	 * not be functional.
2277 	 */
2278 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
2279 		dev_warn(sfp->dev,
2280 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
2281 			 power_mW / 1000, (power_mW / 100) % 10);
2282 		return 0;
2283 	}
2284 
2285 	sfp->module_power_mW = power_mW;
2286 
2287 	return 0;
2288 }
2289 
2290 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
2291 {
2292 	int err;
2293 
2294 	err = sfp_modify_u8(sfp, true, SFP_EXT_STATUS,
2295 			    SFP_EXT_STATUS_PWRLVL_SELECT,
2296 			    enable ? SFP_EXT_STATUS_PWRLVL_SELECT : 0);
2297 	if (err != sizeof(u8)) {
2298 		dev_err(sfp->dev, "failed to %sable high power: %pe\n",
2299 			enable ? "en" : "dis", ERR_PTR(err));
2300 		return -EAGAIN;
2301 	}
2302 
2303 	if (enable)
2304 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
2305 			 sfp->module_power_mW / 1000,
2306 			 (sfp->module_power_mW / 100) % 10);
2307 
2308 	return 0;
2309 }
2310 
2311 static void sfp_module_parse_rate_select(struct sfp *sfp)
2312 {
2313 	u8 rate_id;
2314 
2315 	sfp->rs_threshold_kbd = 0;
2316 	sfp->rs_state_mask = 0;
2317 
2318 	if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_RATE_SELECT)))
2319 		/* No support for RateSelect */
2320 		return;
2321 
2322 	/* Default to INF-8074 RateSelect operation. The signalling threshold
2323 	 * rate is not well specified, so always select "Full Bandwidth", but
2324 	 * SFF-8079 reveals that it is understood that RS0 will be low for
2325 	 * 1.0625Gb/s and high for 2.125Gb/s. Choose a value half-way between.
2326 	 * This method exists prior to SFF-8472.
2327 	 */
2328 	sfp->rs_state_mask = SFP_F_RS0;
2329 	sfp->rs_threshold_kbd = 1594;
2330 
2331 	/* Parse the rate identifier, which is complicated due to history:
2332 	 * SFF-8472 rev 9.5 marks this field as reserved.
2333 	 * SFF-8079 references SFF-8472 rev 9.5 and defines bit 0. SFF-8472
2334 	 *  compliance is not required.
2335 	 * SFF-8472 rev 10.2 defines this field using values 0..4
2336 	 * SFF-8472 rev 11.0 redefines this field with bit 0 for SFF-8079
2337 	 * and even values.
2338 	 */
2339 	rate_id = sfp->id.base.rate_id;
2340 	if (rate_id == 0)
2341 		/* Unspecified */
2342 		return;
2343 
2344 	/* SFF-8472 rev 10.0..10.4 did not account for SFF-8079 using bit 0,
2345 	 * and allocated value 3 to SFF-8431 independent tx/rx rate select.
2346 	 * Convert this to a SFF-8472 rev 11.0 rate identifier.
2347 	 */
2348 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
2349 	    sfp->id.ext.sff8472_compliance < SFP_SFF8472_COMPLIANCE_REV11_0 &&
2350 	    rate_id == 3)
2351 		rate_id = SFF_RID_8431;
2352 
2353 	if (rate_id & SFF_RID_8079) {
2354 		/* SFF-8079 RateSelect / Application Select in conjunction with
2355 		 * SFF-8472 rev 9.5. SFF-8079 defines rate_id as a bitfield
2356 		 * with only bit 0 used, which takes precedence over SFF-8472.
2357 		 */
2358 		if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_APP_SELECT_SFF8079)) {
2359 			/* SFF-8079 Part 1 - rate selection between Fibre
2360 			 * Channel 1.0625/2.125/4.25 Gbd modes. Note that RS0
2361 			 * is high for 2125, so we have to subtract 1 to
2362 			 * include it.
2363 			 */
2364 			sfp->rs_threshold_kbd = 2125 - 1;
2365 			sfp->rs_state_mask = SFP_F_RS0;
2366 		}
2367 		return;
2368 	}
2369 
2370 	/* SFF-8472 rev 9.5 does not define the rate identifier */
2371 	if (sfp->id.ext.sff8472_compliance <= SFP_SFF8472_COMPLIANCE_REV9_5)
2372 		return;
2373 
2374 	/* SFF-8472 rev 11.0 defines rate_id as a numerical value which will
2375 	 * always have bit 0 clear due to SFF-8079's bitfield usage of rate_id.
2376 	 */
2377 	switch (rate_id) {
2378 	case SFF_RID_8431_RX_ONLY:
2379 		sfp->rs_threshold_kbd = 4250;
2380 		sfp->rs_state_mask = SFP_F_RS0;
2381 		break;
2382 
2383 	case SFF_RID_8431_TX_ONLY:
2384 		sfp->rs_threshold_kbd = 4250;
2385 		sfp->rs_state_mask = SFP_F_RS1;
2386 		break;
2387 
2388 	case SFF_RID_8431:
2389 		sfp->rs_threshold_kbd = 4250;
2390 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2391 		break;
2392 
2393 	case SFF_RID_10G8G:
2394 		sfp->rs_threshold_kbd = 9000;
2395 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2396 		break;
2397 	}
2398 }
2399 
2400 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
2401  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
2402  * not support multibyte reads from the EEPROM. Each multi-byte read
2403  * operation returns just one byte of EEPROM followed by zeros. There is
2404  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
2405  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
2406  * name and vendor id into EEPROM, so there is even no way to detect if
2407  * module is V-SOL V2801F. Therefore check for those zeros in the read
2408  * data and then based on check switch to reading EEPROM to one byte
2409  * at a time.
2410  */
2411 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
2412 {
2413 	size_t i, block_size = sfp->i2c_block_size;
2414 
2415 	/* Already using byte IO */
2416 	if (block_size == 1)
2417 		return false;
2418 
2419 	for (i = 1; i < len; i += block_size) {
2420 		if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
2421 			return false;
2422 	}
2423 	return true;
2424 }
2425 
2426 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
2427 {
2428 	u8 check;
2429 	int err;
2430 
2431 	if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
2432 	    id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
2433 	    id->base.connector != SFF8024_CONNECTOR_LC) {
2434 		dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
2435 		id->base.phys_id = SFF8024_ID_SFF_8472;
2436 		id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
2437 		id->base.connector = SFF8024_CONNECTOR_LC;
2438 		err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
2439 		if (err != 3) {
2440 			dev_err(sfp->dev,
2441 				"Failed to rewrite module EEPROM: %pe\n",
2442 				ERR_PTR(err));
2443 			return err;
2444 		}
2445 
2446 		/* Cotsworks modules have been found to require a delay between write operations. */
2447 		mdelay(50);
2448 
2449 		/* Update base structure checksum */
2450 		check = sfp_check(&id->base, sizeof(id->base) - 1);
2451 		err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
2452 		if (err != 1) {
2453 			dev_err(sfp->dev,
2454 				"Failed to update base structure checksum in fiber module EEPROM: %pe\n",
2455 				ERR_PTR(err));
2456 			return err;
2457 		}
2458 	}
2459 	return 0;
2460 }
2461 
2462 static int sfp_module_parse_sff8472(struct sfp *sfp)
2463 {
2464 	/* If the module requires address swap mode, warn about it */
2465 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
2466 		dev_warn(sfp->dev,
2467 			 "module address swap to access page 0xA2 is not supported.\n");
2468 	else
2469 		sfp->have_a2 = true;
2470 
2471 	return 0;
2472 }
2473 
2474 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
2475 {
2476 	/* SFP module inserted - read I2C data */
2477 	struct sfp_eeprom_id id;
2478 	bool cotsworks_sfbg;
2479 	unsigned int mask;
2480 	bool cotsworks;
2481 	u8 check;
2482 	int ret;
2483 
2484 	sfp->i2c_block_size = sfp->i2c_max_block_size;
2485 
2486 	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2487 	if (ret < 0) {
2488 		if (report)
2489 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2490 				ERR_PTR(ret));
2491 		return -EAGAIN;
2492 	}
2493 
2494 	if (ret != sizeof(id.base)) {
2495 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2496 		return -EAGAIN;
2497 	}
2498 
2499 	/* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
2500 	 * address 0x51 is just one byte at a time. Also SFF-8472 requires
2501 	 * that EEPROM supports atomic 16bit read operation for diagnostic
2502 	 * fields, so do not switch to one byte reading at a time unless it
2503 	 * is really required and we have no other option.
2504 	 */
2505 	if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
2506 		dev_info(sfp->dev,
2507 			 "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
2508 		dev_info(sfp->dev,
2509 			 "Switching to reading EEPROM to one byte at a time\n");
2510 		sfp->i2c_block_size = 1;
2511 
2512 		ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2513 		if (ret < 0) {
2514 			if (report)
2515 				dev_err(sfp->dev,
2516 					"failed to read EEPROM: %pe\n",
2517 					ERR_PTR(ret));
2518 			return -EAGAIN;
2519 		}
2520 
2521 		if (ret != sizeof(id.base)) {
2522 			dev_err(sfp->dev, "EEPROM short read: %pe\n",
2523 				ERR_PTR(ret));
2524 			return -EAGAIN;
2525 		}
2526 	}
2527 
2528 	/* Cotsworks do not seem to update the checksums when they
2529 	 * do the final programming with the final module part number,
2530 	 * serial number and date code.
2531 	 */
2532 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
2533 	cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
2534 
2535 	/* Cotsworks SFF module EEPROM do not always have valid phys_id,
2536 	 * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
2537 	 * Cotsworks PN matches and bytes are not correct.
2538 	 */
2539 	if (cotsworks && cotsworks_sfbg) {
2540 		ret = sfp_cotsworks_fixup_check(sfp, &id);
2541 		if (ret < 0)
2542 			return ret;
2543 	}
2544 
2545 	/* Validate the checksum over the base structure */
2546 	check = sfp_check(&id.base, sizeof(id.base) - 1);
2547 	if (check != id.base.cc_base) {
2548 		if (cotsworks) {
2549 			dev_warn(sfp->dev,
2550 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
2551 				 check, id.base.cc_base);
2552 		} else {
2553 			dev_err(sfp->dev,
2554 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
2555 				check, id.base.cc_base);
2556 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2557 				       16, 1, &id, sizeof(id), true);
2558 			return -EINVAL;
2559 		}
2560 	}
2561 
2562 	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
2563 	if (ret < 0) {
2564 		if (report)
2565 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2566 				ERR_PTR(ret));
2567 		return -EAGAIN;
2568 	}
2569 
2570 	if (ret != sizeof(id.ext)) {
2571 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2572 		return -EAGAIN;
2573 	}
2574 
2575 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
2576 	if (check != id.ext.cc_ext) {
2577 		if (cotsworks) {
2578 			dev_warn(sfp->dev,
2579 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
2580 				 check, id.ext.cc_ext);
2581 		} else {
2582 			dev_err(sfp->dev,
2583 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
2584 				check, id.ext.cc_ext);
2585 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2586 				       16, 1, &id, sizeof(id), true);
2587 			memset(&id.ext, 0, sizeof(id.ext));
2588 		}
2589 	}
2590 
2591 	sfp->id = id;
2592 
2593 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
2594 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
2595 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
2596 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
2597 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
2598 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
2599 
2600 	/* Check whether we support this module */
2601 	if (!sfp->type->module_supported(&id)) {
2602 		dev_err(sfp->dev,
2603 			"module is not supported - phys id 0x%02x 0x%02x\n",
2604 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
2605 		return -EINVAL;
2606 	}
2607 
2608 	if (sfp->id.ext.sff8472_compliance != SFP_SFF8472_COMPLIANCE_NONE) {
2609 		ret = sfp_module_parse_sff8472(sfp);
2610 		if (ret < 0)
2611 			return ret;
2612 	}
2613 
2614 	/* Parse the module power requirement */
2615 	ret = sfp_module_parse_power(sfp);
2616 	if (ret < 0)
2617 		return ret;
2618 
2619 	sfp_module_parse_rate_select(sfp);
2620 
2621 	mask = SFP_F_PRESENT;
2622 	if (sfp->gpio[GPIO_TX_DISABLE])
2623 		mask |= SFP_F_TX_DISABLE;
2624 	if (sfp->gpio[GPIO_TX_FAULT])
2625 		mask |= SFP_F_TX_FAULT;
2626 	if (sfp->gpio[GPIO_LOS])
2627 		mask |= SFP_F_LOS;
2628 	if (sfp->gpio[GPIO_RS0])
2629 		mask |= SFP_F_RS0;
2630 	if (sfp->gpio[GPIO_RS1])
2631 		mask |= SFP_F_RS1;
2632 
2633 	sfp->module_t_start_up = T_START_UP;
2634 	sfp->module_t_wait = T_WAIT;
2635 	sfp->phy_t_retry = T_PHY_RETRY;
2636 
2637 	sfp->state_ignore_mask = 0;
2638 
2639 	if (sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SFI ||
2640 	    sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SR ||
2641 	    sfp->id.base.extended_cc == SFF8024_ECC_5GBASE_T ||
2642 	    sfp->id.base.extended_cc == SFF8024_ECC_2_5GBASE_T)
2643 		sfp->mdio_protocol = MDIO_I2C_C45;
2644 	else if (sfp->id.base.e1000_base_t)
2645 		sfp->mdio_protocol = MDIO_I2C_MARVELL_C22;
2646 	else
2647 		sfp->mdio_protocol = MDIO_I2C_NONE;
2648 
2649 	sfp->quirk = sfp_lookup_quirk(&id);
2650 
2651 	mutex_lock(&sfp->st_mutex);
2652 	/* Initialise state bits to use from hardware */
2653 	sfp->state_hw_mask = mask;
2654 
2655 	/* We want to drive the rate select pins that the module is using */
2656 	sfp->state_hw_drive |= sfp->rs_state_mask;
2657 
2658 	if (sfp->quirk && sfp->quirk->fixup)
2659 		sfp->quirk->fixup(sfp);
2660 
2661 	sfp->state_hw_mask &= ~sfp->state_ignore_mask;
2662 	mutex_unlock(&sfp->st_mutex);
2663 
2664 	return 0;
2665 }
2666 
2667 static void sfp_sm_mod_remove(struct sfp *sfp)
2668 {
2669 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
2670 		sfp_module_remove(sfp->sfp_bus);
2671 
2672 	sfp_hwmon_remove(sfp);
2673 
2674 	memset(&sfp->id, 0, sizeof(sfp->id));
2675 	sfp->module_power_mW = 0;
2676 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
2677 	sfp->have_a2 = false;
2678 
2679 	dev_info(sfp->dev, "module removed\n");
2680 }
2681 
2682 /* This state machine tracks the upstream's state */
2683 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
2684 {
2685 	switch (sfp->sm_dev_state) {
2686 	default:
2687 		if (event == SFP_E_DEV_ATTACH)
2688 			sfp->sm_dev_state = SFP_DEV_DOWN;
2689 		break;
2690 
2691 	case SFP_DEV_DOWN:
2692 		if (event == SFP_E_DEV_DETACH)
2693 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2694 		else if (event == SFP_E_DEV_UP)
2695 			sfp->sm_dev_state = SFP_DEV_UP;
2696 		break;
2697 
2698 	case SFP_DEV_UP:
2699 		if (event == SFP_E_DEV_DETACH)
2700 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2701 		else if (event == SFP_E_DEV_DOWN)
2702 			sfp->sm_dev_state = SFP_DEV_DOWN;
2703 		break;
2704 	}
2705 }
2706 
2707 /* This state machine tracks the insert/remove state of the module, probes
2708  * the on-board EEPROM, and sets up the power level.
2709  */
2710 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
2711 {
2712 	int err;
2713 
2714 	/* Handle remove event globally, it resets this state machine */
2715 	if (event == SFP_E_REMOVE) {
2716 		sfp_sm_mod_remove(sfp);
2717 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
2718 		return;
2719 	}
2720 
2721 	/* Handle device detach globally */
2722 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
2723 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
2724 		if (sfp->module_power_mW > 1000 &&
2725 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
2726 			sfp_sm_mod_hpower(sfp, false);
2727 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2728 		return;
2729 	}
2730 
2731 	switch (sfp->sm_mod_state) {
2732 	default:
2733 		if (event == SFP_E_INSERT) {
2734 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
2735 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
2736 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
2737 		}
2738 		break;
2739 
2740 	case SFP_MOD_PROBE:
2741 		/* Wait for T_PROBE_INIT to time out */
2742 		if (event != SFP_E_TIMEOUT)
2743 			break;
2744 
2745 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
2746 		if (err == -EAGAIN) {
2747 			if (sfp->sm_mod_tries_init &&
2748 			   --sfp->sm_mod_tries_init) {
2749 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2750 				break;
2751 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
2752 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
2753 					dev_warn(sfp->dev,
2754 						 "please wait, module slow to respond\n");
2755 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
2756 				break;
2757 			}
2758 		}
2759 		if (err < 0) {
2760 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2761 			break;
2762 		}
2763 
2764 		/* Force a poll to re-read the hardware signal state after
2765 		 * sfp_sm_mod_probe() changed state_hw_mask.
2766 		 */
2767 		mod_delayed_work(system_percpu_wq, &sfp->poll, 1);
2768 
2769 		err = sfp_hwmon_insert(sfp);
2770 		if (err)
2771 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
2772 				 ERR_PTR(err));
2773 
2774 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2775 		fallthrough;
2776 	case SFP_MOD_WAITDEV:
2777 		/* Ensure that the device is attached before proceeding */
2778 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
2779 			break;
2780 
2781 		/* Report the module insertion to the upstream device */
2782 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id,
2783 					sfp->quirk);
2784 		if (err < 0) {
2785 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2786 			break;
2787 		}
2788 
2789 		/* If this is a power level 1 module, we are done */
2790 		if (sfp->module_power_mW <= 1000)
2791 			goto insert;
2792 
2793 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
2794 		fallthrough;
2795 	case SFP_MOD_HPOWER:
2796 		/* Enable high power mode */
2797 		err = sfp_sm_mod_hpower(sfp, true);
2798 		if (err < 0) {
2799 			if (err != -EAGAIN) {
2800 				sfp_module_remove(sfp->sfp_bus);
2801 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2802 			} else {
2803 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2804 			}
2805 			break;
2806 		}
2807 
2808 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
2809 		break;
2810 
2811 	case SFP_MOD_WAITPWR:
2812 		/* Wait for T_HPOWER_LEVEL to time out */
2813 		if (event != SFP_E_TIMEOUT)
2814 			break;
2815 
2816 	insert:
2817 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
2818 		break;
2819 
2820 	case SFP_MOD_PRESENT:
2821 	case SFP_MOD_ERROR:
2822 		break;
2823 	}
2824 }
2825 
2826 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
2827 {
2828 	unsigned long timeout;
2829 	int ret;
2830 
2831 	/* Some events are global */
2832 	if (sfp->sm_state != SFP_S_DOWN &&
2833 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2834 	     sfp->sm_dev_state != SFP_DEV_UP)) {
2835 		if (sfp->sm_state == SFP_S_LINK_UP &&
2836 		    sfp->sm_dev_state == SFP_DEV_UP)
2837 			sfp_sm_link_down(sfp);
2838 		if (sfp->sm_state > SFP_S_INIT)
2839 			sfp_module_stop(sfp->sfp_bus);
2840 		if (sfp->mod_phy)
2841 			sfp_sm_phy_detach(sfp);
2842 		if (sfp->i2c_mii)
2843 			sfp_i2c_mdiobus_destroy(sfp);
2844 		sfp_module_tx_disable(sfp);
2845 		sfp_soft_stop_poll(sfp);
2846 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
2847 		return;
2848 	}
2849 
2850 	/* The main state machine */
2851 	switch (sfp->sm_state) {
2852 	case SFP_S_DOWN:
2853 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2854 		    sfp->sm_dev_state != SFP_DEV_UP)
2855 			break;
2856 
2857 		/* Only use the soft state bits if we have access to the A2h
2858 		 * memory, which implies that we have some level of SFF-8472
2859 		 * compliance.
2860 		 */
2861 		if (sfp->have_a2)
2862 			sfp_soft_start_poll(sfp);
2863 
2864 		sfp_module_tx_enable(sfp);
2865 
2866 		/* Initialise the fault clearance retries */
2867 		sfp->sm_fault_retries = N_FAULT_INIT;
2868 
2869 		/* We need to check the TX_FAULT state, which is not defined
2870 		 * while TX_DISABLE is asserted. The earliest we want to do
2871 		 * anything (such as probe for a PHY) is 50ms (or more on
2872 		 * specific modules).
2873 		 */
2874 		sfp_sm_next(sfp, SFP_S_WAIT, sfp->module_t_wait);
2875 		break;
2876 
2877 	case SFP_S_WAIT:
2878 		if (event != SFP_E_TIMEOUT)
2879 			break;
2880 
2881 		if (sfp->state & SFP_F_TX_FAULT) {
2882 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
2883 			 * from the TX_DISABLE deassertion for the module to
2884 			 * initialise, which is indicated by TX_FAULT
2885 			 * deasserting.
2886 			 */
2887 			timeout = sfp->module_t_start_up;
2888 			if (timeout > sfp->module_t_wait)
2889 				timeout -= sfp->module_t_wait;
2890 			else
2891 				timeout = 1;
2892 
2893 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
2894 		} else {
2895 			/* TX_FAULT is not asserted, assume the module has
2896 			 * finished initialising.
2897 			 */
2898 			goto init_done;
2899 		}
2900 		break;
2901 
2902 	case SFP_S_INIT:
2903 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2904 			/* TX_FAULT is still asserted after t_init
2905 			 * or t_start_up, so assume there is a fault.
2906 			 */
2907 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
2908 				     sfp->sm_fault_retries == N_FAULT_INIT);
2909 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2910 	init_done:
2911 			/* Create mdiobus and start trying for PHY */
2912 			ret = sfp_sm_add_mdio_bus(sfp);
2913 			if (ret < 0) {
2914 				sfp_sm_next(sfp, SFP_S_FAIL, 0);
2915 				break;
2916 			}
2917 			sfp->sm_phy_retries = R_PHY_RETRY;
2918 			goto phy_probe;
2919 		}
2920 		break;
2921 
2922 	case SFP_S_INIT_PHY:
2923 		if (event != SFP_E_TIMEOUT)
2924 			break;
2925 	phy_probe:
2926 		/* TX_FAULT deasserted or we timed out with TX_FAULT
2927 		 * clear.  Probe for the PHY and check the LOS state.
2928 		 */
2929 		ret = sfp_sm_probe_for_phy(sfp);
2930 		if (ret == -ENODEV) {
2931 			if (--sfp->sm_phy_retries) {
2932 				sfp_sm_next(sfp, SFP_S_INIT_PHY,
2933 					    sfp->phy_t_retry);
2934 				dev_dbg(sfp->dev,
2935 					"no PHY detected, %u tries left\n",
2936 					sfp->sm_phy_retries);
2937 				break;
2938 			} else {
2939 				dev_info(sfp->dev, "no PHY detected\n");
2940 			}
2941 		} else if (ret) {
2942 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2943 			break;
2944 		}
2945 		if (sfp_module_start(sfp->sfp_bus)) {
2946 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2947 			break;
2948 		}
2949 		sfp_sm_link_check_los(sfp);
2950 
2951 		/* Reset the fault retry count */
2952 		sfp->sm_fault_retries = N_FAULT;
2953 		break;
2954 
2955 	case SFP_S_INIT_TX_FAULT:
2956 		if (event == SFP_E_TIMEOUT) {
2957 			sfp_module_tx_fault_reset(sfp);
2958 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
2959 		}
2960 		break;
2961 
2962 	case SFP_S_WAIT_LOS:
2963 		if (event == SFP_E_TX_FAULT)
2964 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2965 		else if (sfp_los_event_inactive(sfp, event))
2966 			sfp_sm_link_up(sfp);
2967 		break;
2968 
2969 	case SFP_S_LINK_UP:
2970 		if (event == SFP_E_TX_FAULT) {
2971 			sfp_sm_link_down(sfp);
2972 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2973 		} else if (sfp_los_event_active(sfp, event)) {
2974 			sfp_sm_link_down(sfp);
2975 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2976 		}
2977 		break;
2978 
2979 	case SFP_S_TX_FAULT:
2980 		if (event == SFP_E_TIMEOUT) {
2981 			sfp_module_tx_fault_reset(sfp);
2982 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2983 		}
2984 		break;
2985 
2986 	case SFP_S_REINIT:
2987 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2988 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2989 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2990 			dev_info(sfp->dev, "module transmit fault recovered\n");
2991 			sfp_sm_link_check_los(sfp);
2992 		}
2993 		break;
2994 
2995 	case SFP_S_TX_DISABLE:
2996 		break;
2997 	}
2998 }
2999 
3000 static void __sfp_sm_event(struct sfp *sfp, unsigned int event)
3001 {
3002 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
3003 		mod_state_to_str(sfp->sm_mod_state),
3004 		dev_state_to_str(sfp->sm_dev_state),
3005 		sm_state_to_str(sfp->sm_state),
3006 		event_to_str(event));
3007 
3008 	sfp_sm_device(sfp, event);
3009 	sfp_sm_module(sfp, event);
3010 	sfp_sm_main(sfp, event);
3011 
3012 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
3013 		mod_state_to_str(sfp->sm_mod_state),
3014 		dev_state_to_str(sfp->sm_dev_state),
3015 		sm_state_to_str(sfp->sm_state));
3016 }
3017 
3018 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
3019 {
3020 	mutex_lock(&sfp->sm_mutex);
3021 	__sfp_sm_event(sfp, event);
3022 	mutex_unlock(&sfp->sm_mutex);
3023 }
3024 
3025 static void sfp_attach(struct sfp *sfp)
3026 {
3027 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
3028 }
3029 
3030 static void sfp_detach(struct sfp *sfp)
3031 {
3032 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
3033 }
3034 
3035 static void sfp_start(struct sfp *sfp)
3036 {
3037 	sfp_sm_event(sfp, SFP_E_DEV_UP);
3038 }
3039 
3040 static void sfp_stop(struct sfp *sfp)
3041 {
3042 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
3043 }
3044 
3045 static void sfp_set_signal_rate(struct sfp *sfp, unsigned int rate_kbd)
3046 {
3047 	unsigned int set;
3048 
3049 	sfp->rate_kbd = rate_kbd;
3050 
3051 	if (rate_kbd > sfp->rs_threshold_kbd)
3052 		set = sfp->rs_state_mask;
3053 	else
3054 		set = 0;
3055 
3056 	sfp_mod_state(sfp, SFP_F_RS0 | SFP_F_RS1, set);
3057 }
3058 
3059 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
3060 {
3061 	/* locking... and check module is present */
3062 
3063 	if (sfp->id.ext.sff8472_compliance &&
3064 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
3065 		modinfo->type = ETH_MODULE_SFF_8472;
3066 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
3067 	} else {
3068 		modinfo->type = ETH_MODULE_SFF_8079;
3069 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
3070 	}
3071 	return 0;
3072 }
3073 
3074 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
3075 			     u8 *data)
3076 {
3077 	unsigned int first, last, len;
3078 	int ret;
3079 
3080 	if (!(sfp->state & SFP_F_PRESENT))
3081 		return -ENODEV;
3082 
3083 	if (ee->len == 0)
3084 		return -EINVAL;
3085 
3086 	first = ee->offset;
3087 	last = ee->offset + ee->len;
3088 	if (first < ETH_MODULE_SFF_8079_LEN) {
3089 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
3090 		len -= first;
3091 
3092 		ret = sfp_read(sfp, false, first, data, len);
3093 		if (ret < 0)
3094 			return ret;
3095 
3096 		first += len;
3097 		data += len;
3098 	}
3099 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
3100 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
3101 		len -= first;
3102 		first -= ETH_MODULE_SFF_8079_LEN;
3103 
3104 		ret = sfp_read(sfp, true, first, data, len);
3105 		if (ret < 0)
3106 			return ret;
3107 	}
3108 	return 0;
3109 }
3110 
3111 static int sfp_module_eeprom_by_page(struct sfp *sfp,
3112 				     const struct ethtool_module_eeprom *page,
3113 				     struct netlink_ext_ack *extack)
3114 {
3115 	if (!(sfp->state & SFP_F_PRESENT))
3116 		return -ENODEV;
3117 
3118 	if (page->bank) {
3119 		NL_SET_ERR_MSG(extack, "Banks not supported");
3120 		return -EOPNOTSUPP;
3121 	}
3122 
3123 	if (page->page) {
3124 		NL_SET_ERR_MSG(extack, "Only page 0 supported");
3125 		return -EOPNOTSUPP;
3126 	}
3127 
3128 	if (page->i2c_address != 0x50 &&
3129 	    page->i2c_address != 0x51) {
3130 		NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
3131 		return -EOPNOTSUPP;
3132 	}
3133 
3134 	return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
3135 			page->data, page->length);
3136 };
3137 
3138 static const struct sfp_socket_ops sfp_module_ops = {
3139 	.attach = sfp_attach,
3140 	.detach = sfp_detach,
3141 	.start = sfp_start,
3142 	.stop = sfp_stop,
3143 	.set_signal_rate = sfp_set_signal_rate,
3144 	.module_info = sfp_module_info,
3145 	.module_eeprom = sfp_module_eeprom,
3146 	.module_eeprom_by_page = sfp_module_eeprom_by_page,
3147 };
3148 
3149 static void sfp_timeout(struct work_struct *work)
3150 {
3151 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
3152 
3153 	rtnl_lock();
3154 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
3155 	rtnl_unlock();
3156 }
3157 
3158 static void sfp_check_state(struct sfp *sfp)
3159 {
3160 	unsigned int state, i, changed;
3161 
3162 	rtnl_lock();
3163 	mutex_lock(&sfp->st_mutex);
3164 	state = sfp_get_state(sfp);
3165 	changed = state ^ sfp->state;
3166 	changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
3167 
3168 	for (i = 0; i < GPIO_MAX; i++)
3169 		if (changed & BIT(i))
3170 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_names[i],
3171 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
3172 
3173 	state |= sfp->state & SFP_F_OUTPUTS;
3174 	sfp->state = state;
3175 	mutex_unlock(&sfp->st_mutex);
3176 
3177 	mutex_lock(&sfp->sm_mutex);
3178 	if (changed & SFP_F_PRESENT)
3179 		__sfp_sm_event(sfp, state & SFP_F_PRESENT ?
3180 				    SFP_E_INSERT : SFP_E_REMOVE);
3181 
3182 	if (changed & SFP_F_TX_FAULT)
3183 		__sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
3184 				    SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
3185 
3186 	if (changed & SFP_F_LOS)
3187 		__sfp_sm_event(sfp, state & SFP_F_LOS ?
3188 				    SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
3189 	mutex_unlock(&sfp->sm_mutex);
3190 	rtnl_unlock();
3191 }
3192 
3193 static irqreturn_t sfp_irq(int irq, void *data)
3194 {
3195 	struct sfp *sfp = data;
3196 
3197 	sfp_check_state(sfp);
3198 
3199 	return IRQ_HANDLED;
3200 }
3201 
3202 static void sfp_poll(struct work_struct *work)
3203 {
3204 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
3205 
3206 	sfp_check_state(sfp);
3207 
3208 	// st_mutex doesn't need to be held here for state_soft_mask,
3209 	// it's unimportant if we race while reading this.
3210 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
3211 	    sfp->need_poll)
3212 		sfp_schedule_poll(sfp);
3213 }
3214 
3215 static struct sfp *sfp_alloc(struct device *dev)
3216 {
3217 	struct sfp *sfp;
3218 
3219 	sfp = kzalloc_obj(*sfp);
3220 	if (!sfp)
3221 		return ERR_PTR(-ENOMEM);
3222 
3223 	sfp->dev = dev;
3224 
3225 	mutex_init(&sfp->sm_mutex);
3226 	mutex_init(&sfp->st_mutex);
3227 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
3228 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
3229 
3230 	sfp_hwmon_init(sfp);
3231 
3232 	return sfp;
3233 }
3234 
3235 static void sfp_cleanup(void *data)
3236 {
3237 	struct sfp *sfp = data;
3238 
3239 	sfp_hwmon_exit(sfp);
3240 
3241 	cancel_delayed_work_sync(&sfp->poll);
3242 	cancel_delayed_work_sync(&sfp->timeout);
3243 	if (sfp->i2c_mii) {
3244 		mdiobus_unregister(sfp->i2c_mii);
3245 		mdiobus_free(sfp->i2c_mii);
3246 	}
3247 	if (sfp->i2c)
3248 		i2c_put_adapter(sfp->i2c);
3249 	kfree(sfp);
3250 }
3251 
3252 static int sfp_i2c_get(struct sfp *sfp)
3253 {
3254 	struct fwnode_handle *h;
3255 	struct i2c_adapter *i2c;
3256 	int err;
3257 
3258 	h = fwnode_find_reference(dev_fwnode(sfp->dev), "i2c-bus", 0);
3259 	if (IS_ERR(h)) {
3260 		dev_err(sfp->dev, "missing 'i2c-bus' property\n");
3261 		return -ENODEV;
3262 	}
3263 
3264 	i2c = i2c_get_adapter_by_fwnode(h);
3265 	if (!i2c) {
3266 		err = -EPROBE_DEFER;
3267 		goto put;
3268 	}
3269 
3270 	err = sfp_i2c_configure(sfp, i2c);
3271 	if (err)
3272 		i2c_put_adapter(i2c);
3273 put:
3274 	fwnode_handle_put(h);
3275 	return err;
3276 }
3277 
3278 static int sfp_probe(struct platform_device *pdev)
3279 {
3280 	const struct sff_data *sff;
3281 	char *sfp_irq_name;
3282 	struct sfp *sfp;
3283 	int err, i;
3284 
3285 	sfp = sfp_alloc(&pdev->dev);
3286 	if (IS_ERR(sfp))
3287 		return PTR_ERR(sfp);
3288 
3289 	platform_set_drvdata(pdev, sfp);
3290 
3291 	err = devm_add_action_or_reset(sfp->dev, sfp_cleanup, sfp);
3292 	if (err < 0)
3293 		return err;
3294 
3295 	sff = device_get_match_data(sfp->dev);
3296 	if (!sff)
3297 		sff = &sfp_data;
3298 
3299 	sfp->type = sff;
3300 
3301 	err = sfp_i2c_get(sfp);
3302 	if (err)
3303 		return err;
3304 
3305 	for (i = 0; i < GPIO_MAX; i++)
3306 		if (sff->gpios & BIT(i)) {
3307 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
3308 					   gpio_names[i], gpio_flags[i]);
3309 			if (IS_ERR(sfp->gpio[i]))
3310 				return PTR_ERR(sfp->gpio[i]);
3311 		}
3312 
3313 	sfp->state_hw_mask = SFP_F_PRESENT;
3314 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
3315 
3316 	sfp->get_state = sfp_gpio_get_state;
3317 	sfp->set_state = sfp_gpio_set_state;
3318 
3319 	/* An SFP cage with no MOD_DEF0 GPIO has no hardware presence signal.
3320 	 * Assuming the module is always present traps an empty cage in
3321 	 * MOD_ERROR and never detects hot-insertion, so derive presence from a
3322 	 * throttled I2C probe and poll for changes instead. sfp_i2c_configure()
3323 	 * has already set i2c_max_block_size; seed i2c_block_size so the
3324 	 * presence read does not issue a zero-length transfer before the first
3325 	 * EEPROM read. Seed i2c_present_next to jiffies so the first probe
3326 	 * happens immediately (a zero value would be in the past relative to
3327 	 * the negative INITIAL_JIFFIES at boot and delay detection).
3328 	 *
3329 	 * A soldered-down module (sff,sff) has no presence signal and is
3330 	 * genuinely always present, so it keeps the always-present behaviour;
3331 	 * the I2C probe is gated on the cage type advertising SFP_F_PRESENT.
3332 	 */
3333 	if (!sfp->gpio[GPIO_MODDEF0]) {
3334 		if (sff->gpios & SFP_F_PRESENT) {
3335 			sfp->get_state = sfp_i2c_get_state;
3336 			sfp->i2c_block_size = sfp->i2c_max_block_size;
3337 			sfp->i2c_present_next = jiffies;
3338 			sfp->need_poll = true;
3339 		} else {
3340 			sfp->get_state = sff_gpio_get_state;
3341 		}
3342 	}
3343 
3344 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
3345 				 &sfp->max_power_mW);
3346 	if (sfp->max_power_mW < 1000) {
3347 		if (sfp->max_power_mW)
3348 			dev_warn(sfp->dev,
3349 				 "Firmware bug: host maximum power should be at least 1W\n");
3350 		sfp->max_power_mW = 1000;
3351 	}
3352 
3353 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
3354 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
3355 
3356 	/* Get the initial state, and always signal TX disable,
3357 	 * since the network interface will not be up.
3358 	 */
3359 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
3360 
3361 	if (sfp->gpio[GPIO_RS0] &&
3362 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RS0]))
3363 		sfp->state |= SFP_F_RS0;
3364 	sfp_set_state(sfp, sfp->state);
3365 	sfp_module_tx_disable(sfp);
3366 	if (sfp->state & SFP_F_PRESENT) {
3367 		rtnl_lock();
3368 		sfp_sm_event(sfp, SFP_E_INSERT);
3369 		rtnl_unlock();
3370 	}
3371 
3372 	for (i = 0; i < GPIO_MAX; i++) {
3373 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
3374 			continue;
3375 
3376 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
3377 		if (sfp->gpio_irq[i] < 0) {
3378 			sfp->gpio_irq[i] = 0;
3379 			sfp->need_poll = true;
3380 			continue;
3381 		}
3382 
3383 		sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
3384 					      "%s-%s", dev_name(sfp->dev),
3385 					      gpio_names[i]);
3386 
3387 		if (!sfp_irq_name)
3388 			return -ENOMEM;
3389 
3390 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
3391 						NULL, sfp_irq,
3392 						IRQF_ONESHOT |
3393 						IRQF_TRIGGER_RISING |
3394 						IRQF_TRIGGER_FALLING,
3395 						sfp_irq_name, sfp);
3396 		if (err) {
3397 			sfp->gpio_irq[i] = 0;
3398 			sfp->need_poll = true;
3399 		}
3400 	}
3401 
3402 	if (sfp->need_poll)
3403 		sfp_schedule_poll(sfp);
3404 
3405 	/* We could have an issue in cases no Tx disable pin is available or
3406 	 * wired as modules using a laser as their light source will continue to
3407 	 * be active when the fiber is removed. This could be a safety issue and
3408 	 * we should at least warn the user about that.
3409 	 */
3410 	if (!sfp->gpio[GPIO_TX_DISABLE])
3411 		dev_warn(sfp->dev,
3412 			 "No tx_disable pin: SFP modules will always be emitting.\n");
3413 
3414 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
3415 	if (!sfp->sfp_bus)
3416 		return -ENOMEM;
3417 
3418 	if (sfp->i2c_max_block_size < 2)
3419 		dev_warn(sfp->dev,
3420 			 "Please note:\n"
3421 			 "This SFP cage is accessed via an SMBus only capable of single byte\n"
3422 			 "transactions. Some features are disabled, other may be unreliable or\n"
3423 			 "sporadically fail. Use with caution. There is nothing that the kernel\n"
3424 			 "or community can do to fix it, the kernel will try best efforts. Please\n"
3425 			 "verify any problems on hardware that supports multi-byte I2C transactions.\n");
3426 
3427 	sfp_debugfs_init(sfp);
3428 
3429 	return 0;
3430 }
3431 
3432 static void sfp_remove(struct platform_device *pdev)
3433 {
3434 	struct sfp *sfp = platform_get_drvdata(pdev);
3435 
3436 	sfp_debugfs_exit(sfp);
3437 	sfp_unregister_socket(sfp->sfp_bus);
3438 
3439 	rtnl_lock();
3440 	sfp_sm_event(sfp, SFP_E_REMOVE);
3441 	rtnl_unlock();
3442 }
3443 
3444 static void sfp_shutdown(struct platform_device *pdev)
3445 {
3446 	struct sfp *sfp = platform_get_drvdata(pdev);
3447 	int i;
3448 
3449 	for (i = 0; i < GPIO_MAX; i++) {
3450 		if (!sfp->gpio_irq[i])
3451 			continue;
3452 
3453 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
3454 	}
3455 
3456 	cancel_delayed_work_sync(&sfp->poll);
3457 	cancel_delayed_work_sync(&sfp->timeout);
3458 }
3459 
3460 static struct platform_driver sfp_driver = {
3461 	.probe = sfp_probe,
3462 	.remove = sfp_remove,
3463 	.shutdown = sfp_shutdown,
3464 	.driver = {
3465 		.name = "sfp",
3466 		.of_match_table = sfp_of_match,
3467 	},
3468 };
3469 
3470 module_platform_driver(sfp_driver);
3471 
3472 MODULE_ALIAS("platform:sfp");
3473 MODULE_AUTHOR("Russell King");
3474 MODULE_LICENSE("GPL v2");
3475 MODULE_DESCRIPTION("SFP cage support");
3476