xref: /openbmc/linux/drivers/net/phy/sfp.c (revision e2ad626f)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/debugfs.h>
3 #include <linux/delay.h>
4 #include <linux/gpio/consumer.h>
5 #include <linux/hwmon.h>
6 #include <linux/i2c.h>
7 #include <linux/interrupt.h>
8 #include <linux/jiffies.h>
9 #include <linux/mdio/mdio-i2c.h>
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/of.h>
13 #include <linux/phy.h>
14 #include <linux/platform_device.h>
15 #include <linux/rtnetlink.h>
16 #include <linux/slab.h>
17 #include <linux/workqueue.h>
18 
19 #include "sfp.h"
20 #include "swphy.h"
21 
22 enum {
23 	GPIO_MODDEF0,
24 	GPIO_LOS,
25 	GPIO_TX_FAULT,
26 	GPIO_TX_DISABLE,
27 	GPIO_RS0,
28 	GPIO_RS1,
29 	GPIO_MAX,
30 
31 	SFP_F_PRESENT = BIT(GPIO_MODDEF0),
32 	SFP_F_LOS = BIT(GPIO_LOS),
33 	SFP_F_TX_FAULT = BIT(GPIO_TX_FAULT),
34 	SFP_F_TX_DISABLE = BIT(GPIO_TX_DISABLE),
35 	SFP_F_RS0 = BIT(GPIO_RS0),
36 	SFP_F_RS1 = BIT(GPIO_RS1),
37 
38 	SFP_F_OUTPUTS = SFP_F_TX_DISABLE | SFP_F_RS0 | SFP_F_RS1,
39 
40 	SFP_E_INSERT = 0,
41 	SFP_E_REMOVE,
42 	SFP_E_DEV_ATTACH,
43 	SFP_E_DEV_DETACH,
44 	SFP_E_DEV_DOWN,
45 	SFP_E_DEV_UP,
46 	SFP_E_TX_FAULT,
47 	SFP_E_TX_CLEAR,
48 	SFP_E_LOS_HIGH,
49 	SFP_E_LOS_LOW,
50 	SFP_E_TIMEOUT,
51 
52 	SFP_MOD_EMPTY = 0,
53 	SFP_MOD_ERROR,
54 	SFP_MOD_PROBE,
55 	SFP_MOD_WAITDEV,
56 	SFP_MOD_HPOWER,
57 	SFP_MOD_WAITPWR,
58 	SFP_MOD_PRESENT,
59 
60 	SFP_DEV_DETACHED = 0,
61 	SFP_DEV_DOWN,
62 	SFP_DEV_UP,
63 
64 	SFP_S_DOWN = 0,
65 	SFP_S_FAIL,
66 	SFP_S_WAIT,
67 	SFP_S_INIT,
68 	SFP_S_INIT_PHY,
69 	SFP_S_INIT_TX_FAULT,
70 	SFP_S_WAIT_LOS,
71 	SFP_S_LINK_UP,
72 	SFP_S_TX_FAULT,
73 	SFP_S_REINIT,
74 	SFP_S_TX_DISABLE,
75 };
76 
77 static const char  * const mod_state_strings[] = {
78 	[SFP_MOD_EMPTY] = "empty",
79 	[SFP_MOD_ERROR] = "error",
80 	[SFP_MOD_PROBE] = "probe",
81 	[SFP_MOD_WAITDEV] = "waitdev",
82 	[SFP_MOD_HPOWER] = "hpower",
83 	[SFP_MOD_WAITPWR] = "waitpwr",
84 	[SFP_MOD_PRESENT] = "present",
85 };
86 
87 static const char *mod_state_to_str(unsigned short mod_state)
88 {
89 	if (mod_state >= ARRAY_SIZE(mod_state_strings))
90 		return "Unknown module state";
91 	return mod_state_strings[mod_state];
92 }
93 
94 static const char * const dev_state_strings[] = {
95 	[SFP_DEV_DETACHED] = "detached",
96 	[SFP_DEV_DOWN] = "down",
97 	[SFP_DEV_UP] = "up",
98 };
99 
100 static const char *dev_state_to_str(unsigned short dev_state)
101 {
102 	if (dev_state >= ARRAY_SIZE(dev_state_strings))
103 		return "Unknown device state";
104 	return dev_state_strings[dev_state];
105 }
106 
107 static const char * const event_strings[] = {
108 	[SFP_E_INSERT] = "insert",
109 	[SFP_E_REMOVE] = "remove",
110 	[SFP_E_DEV_ATTACH] = "dev_attach",
111 	[SFP_E_DEV_DETACH] = "dev_detach",
112 	[SFP_E_DEV_DOWN] = "dev_down",
113 	[SFP_E_DEV_UP] = "dev_up",
114 	[SFP_E_TX_FAULT] = "tx_fault",
115 	[SFP_E_TX_CLEAR] = "tx_clear",
116 	[SFP_E_LOS_HIGH] = "los_high",
117 	[SFP_E_LOS_LOW] = "los_low",
118 	[SFP_E_TIMEOUT] = "timeout",
119 };
120 
121 static const char *event_to_str(unsigned short event)
122 {
123 	if (event >= ARRAY_SIZE(event_strings))
124 		return "Unknown event";
125 	return event_strings[event];
126 }
127 
128 static const char * const sm_state_strings[] = {
129 	[SFP_S_DOWN] = "down",
130 	[SFP_S_FAIL] = "fail",
131 	[SFP_S_WAIT] = "wait",
132 	[SFP_S_INIT] = "init",
133 	[SFP_S_INIT_PHY] = "init_phy",
134 	[SFP_S_INIT_TX_FAULT] = "init_tx_fault",
135 	[SFP_S_WAIT_LOS] = "wait_los",
136 	[SFP_S_LINK_UP] = "link_up",
137 	[SFP_S_TX_FAULT] = "tx_fault",
138 	[SFP_S_REINIT] = "reinit",
139 	[SFP_S_TX_DISABLE] = "tx_disable",
140 };
141 
142 static const char *sm_state_to_str(unsigned short sm_state)
143 {
144 	if (sm_state >= ARRAY_SIZE(sm_state_strings))
145 		return "Unknown state";
146 	return sm_state_strings[sm_state];
147 }
148 
149 static const char *gpio_names[] = {
150 	"mod-def0",
151 	"los",
152 	"tx-fault",
153 	"tx-disable",
154 	"rate-select0",
155 	"rate-select1",
156 };
157 
158 static const enum gpiod_flags gpio_flags[] = {
159 	GPIOD_IN,
160 	GPIOD_IN,
161 	GPIOD_IN,
162 	GPIOD_ASIS,
163 	GPIOD_ASIS,
164 	GPIOD_ASIS,
165 };
166 
167 /* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
168  * non-cooled module to initialise its laser safety circuitry. We wait
169  * an initial T_WAIT period before we check the tx fault to give any PHY
170  * on board (for a copper SFP) time to initialise.
171  */
172 #define T_WAIT			msecs_to_jiffies(50)
173 #define T_START_UP		msecs_to_jiffies(300)
174 #define T_START_UP_BAD_GPON	msecs_to_jiffies(60000)
175 
176 /* t_reset is the time required to assert the TX_DISABLE signal to reset
177  * an indicated TX_FAULT.
178  */
179 #define T_RESET_US		10
180 #define T_FAULT_RECOVER		msecs_to_jiffies(1000)
181 
182 /* N_FAULT_INIT is the number of recovery attempts at module initialisation
183  * time. If the TX_FAULT signal is not deasserted after this number of
184  * attempts at clearing it, we decide that the module is faulty.
185  * N_FAULT is the same but after the module has initialised.
186  */
187 #define N_FAULT_INIT		5
188 #define N_FAULT			5
189 
190 /* T_PHY_RETRY is the time interval between attempts to probe the PHY.
191  * R_PHY_RETRY is the number of attempts.
192  */
193 #define T_PHY_RETRY		msecs_to_jiffies(50)
194 #define R_PHY_RETRY		12
195 
196 /* SFP module presence detection is poor: the three MOD DEF signals are
197  * the same length on the PCB, which means it's possible for MOD DEF 0 to
198  * connect before the I2C bus on MOD DEF 1/2.
199  *
200  * The SFF-8472 specifies t_serial ("Time from power on until module is
201  * ready for data transmission over the two wire serial bus.") as 300ms.
202  */
203 #define T_SERIAL		msecs_to_jiffies(300)
204 #define T_HPOWER_LEVEL		msecs_to_jiffies(300)
205 #define T_PROBE_RETRY_INIT	msecs_to_jiffies(100)
206 #define R_PROBE_RETRY_INIT	10
207 #define T_PROBE_RETRY_SLOW	msecs_to_jiffies(5000)
208 #define R_PROBE_RETRY_SLOW	12
209 
210 /* SFP modules appear to always have their PHY configured for bus address
211  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
212  * RollBall SFPs access phy via SFP Enhanced Digital Diagnostic Interface
213  * via address 0x51 (mdio-i2c will use RollBall protocol on this address).
214  */
215 #define SFP_PHY_ADDR		22
216 #define SFP_PHY_ADDR_ROLLBALL	17
217 
218 /* SFP_EEPROM_BLOCK_SIZE is the size of data chunk to read the EEPROM
219  * at a time. Some SFP modules and also some Linux I2C drivers do not like
220  * reads longer than 16 bytes.
221  */
222 #define SFP_EEPROM_BLOCK_SIZE	16
223 
224 struct sff_data {
225 	unsigned int gpios;
226 	bool (*module_supported)(const struct sfp_eeprom_id *id);
227 };
228 
229 struct sfp {
230 	struct device *dev;
231 	struct i2c_adapter *i2c;
232 	struct mii_bus *i2c_mii;
233 	struct sfp_bus *sfp_bus;
234 	enum mdio_i2c_proto mdio_protocol;
235 	struct phy_device *mod_phy;
236 	const struct sff_data *type;
237 	size_t i2c_block_size;
238 	u32 max_power_mW;
239 
240 	unsigned int (*get_state)(struct sfp *);
241 	void (*set_state)(struct sfp *, unsigned int);
242 	int (*read)(struct sfp *, bool, u8, void *, size_t);
243 	int (*write)(struct sfp *, bool, u8, void *, size_t);
244 
245 	struct gpio_desc *gpio[GPIO_MAX];
246 	int gpio_irq[GPIO_MAX];
247 
248 	bool need_poll;
249 
250 	/* Access rules:
251 	 * state_hw_drive: st_mutex held
252 	 * state_hw_mask: st_mutex held
253 	 * state_soft_mask: st_mutex held
254 	 * state: st_mutex held unless reading input bits
255 	 */
256 	struct mutex st_mutex;			/* Protects state */
257 	unsigned int state_hw_drive;
258 	unsigned int state_hw_mask;
259 	unsigned int state_soft_mask;
260 	unsigned int state;
261 
262 	struct delayed_work poll;
263 	struct delayed_work timeout;
264 	struct mutex sm_mutex;			/* Protects state machine */
265 	unsigned char sm_mod_state;
266 	unsigned char sm_mod_tries_init;
267 	unsigned char sm_mod_tries;
268 	unsigned char sm_dev_state;
269 	unsigned short sm_state;
270 	unsigned char sm_fault_retries;
271 	unsigned char sm_phy_retries;
272 
273 	struct sfp_eeprom_id id;
274 	unsigned int module_power_mW;
275 	unsigned int module_t_start_up;
276 	unsigned int module_t_wait;
277 
278 	unsigned int rate_kbd;
279 	unsigned int rs_threshold_kbd;
280 	unsigned int rs_state_mask;
281 
282 	bool have_a2;
283 	bool tx_fault_ignore;
284 
285 	const struct sfp_quirk *quirk;
286 
287 #if IS_ENABLED(CONFIG_HWMON)
288 	struct sfp_diag diag;
289 	struct delayed_work hwmon_probe;
290 	unsigned int hwmon_tries;
291 	struct device *hwmon_dev;
292 	char *hwmon_name;
293 #endif
294 
295 #if IS_ENABLED(CONFIG_DEBUG_FS)
296 	struct dentry *debugfs_dir;
297 #endif
298 };
299 
300 static bool sff_module_supported(const struct sfp_eeprom_id *id)
301 {
302 	return id->base.phys_id == SFF8024_ID_SFF_8472 &&
303 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
304 }
305 
306 static const struct sff_data sff_data = {
307 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
308 	.module_supported = sff_module_supported,
309 };
310 
311 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
312 {
313 	if (id->base.phys_id == SFF8024_ID_SFP &&
314 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP)
315 		return true;
316 
317 	/* SFP GPON module Ubiquiti U-Fiber Instant has in its EEPROM stored
318 	 * phys id SFF instead of SFP. Therefore mark this module explicitly
319 	 * as supported based on vendor name and pn match.
320 	 */
321 	if (id->base.phys_id == SFF8024_ID_SFF_8472 &&
322 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP &&
323 	    !memcmp(id->base.vendor_name, "UBNT            ", 16) &&
324 	    !memcmp(id->base.vendor_pn, "UF-INSTANT      ", 16))
325 		return true;
326 
327 	return false;
328 }
329 
330 static const struct sff_data sfp_data = {
331 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
332 		 SFP_F_TX_DISABLE | SFP_F_RS0 | SFP_F_RS1,
333 	.module_supported = sfp_module_supported,
334 };
335 
336 static const struct of_device_id sfp_of_match[] = {
337 	{ .compatible = "sff,sff", .data = &sff_data, },
338 	{ .compatible = "sff,sfp", .data = &sfp_data, },
339 	{ },
340 };
341 MODULE_DEVICE_TABLE(of, sfp_of_match);
342 
343 static void sfp_fixup_long_startup(struct sfp *sfp)
344 {
345 	sfp->module_t_start_up = T_START_UP_BAD_GPON;
346 }
347 
348 static void sfp_fixup_ignore_tx_fault(struct sfp *sfp)
349 {
350 	sfp->tx_fault_ignore = true;
351 }
352 
353 // For 10GBASE-T short-reach modules
354 static void sfp_fixup_10gbaset_30m(struct sfp *sfp)
355 {
356 	sfp->id.base.connector = SFF8024_CONNECTOR_RJ45;
357 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SR;
358 }
359 
360 static void sfp_fixup_rollball_proto(struct sfp *sfp, unsigned int secs)
361 {
362 	sfp->mdio_protocol = MDIO_I2C_ROLLBALL;
363 	sfp->module_t_wait = msecs_to_jiffies(secs * 1000);
364 }
365 
366 static void sfp_fixup_fs_10gt(struct sfp *sfp)
367 {
368 	sfp_fixup_10gbaset_30m(sfp);
369 
370 	// These SFPs need 4 seconds before the PHY can be accessed
371 	sfp_fixup_rollball_proto(sfp, 4);
372 }
373 
374 static void sfp_fixup_halny_gsfp(struct sfp *sfp)
375 {
376 	/* Ignore the TX_FAULT and LOS signals on this module.
377 	 * these are possibly used for other purposes on this
378 	 * module, e.g. a serial port.
379 	 */
380 	sfp->state_hw_mask &= ~(SFP_F_TX_FAULT | SFP_F_LOS);
381 }
382 
383 static void sfp_fixup_rollball(struct sfp *sfp)
384 {
385 	// Rollball SFPs need 25 seconds before the PHY can be accessed
386 	sfp_fixup_rollball_proto(sfp, 25);
387 }
388 
389 static void sfp_fixup_rollball_cc(struct sfp *sfp)
390 {
391 	sfp_fixup_rollball(sfp);
392 
393 	/* Some RollBall SFPs may have wrong (zero) extended compliance code
394 	 * burned in EEPROM. For PHY probing we need the correct one.
395 	 */
396 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SFI;
397 }
398 
399 static void sfp_quirk_2500basex(const struct sfp_eeprom_id *id,
400 				unsigned long *modes,
401 				unsigned long *interfaces)
402 {
403 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseX_Full_BIT, modes);
404 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
405 }
406 
407 static void sfp_quirk_disable_autoneg(const struct sfp_eeprom_id *id,
408 				      unsigned long *modes,
409 				      unsigned long *interfaces)
410 {
411 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, modes);
412 }
413 
414 static void sfp_quirk_oem_2_5g(const struct sfp_eeprom_id *id,
415 			       unsigned long *modes,
416 			       unsigned long *interfaces)
417 {
418 	/* Copper 2.5G SFP */
419 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT, modes);
420 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
421 	sfp_quirk_disable_autoneg(id, modes, interfaces);
422 }
423 
424 static void sfp_quirk_ubnt_uf_instant(const struct sfp_eeprom_id *id,
425 				      unsigned long *modes,
426 				      unsigned long *interfaces)
427 {
428 	/* Ubiquiti U-Fiber Instant module claims that support all transceiver
429 	 * types including 10G Ethernet which is not truth. So clear all claimed
430 	 * modes and set only one mode which module supports: 1000baseX_Full.
431 	 */
432 	linkmode_zero(modes);
433 	linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT, modes);
434 }
435 
436 #define SFP_QUIRK(_v, _p, _m, _f) \
437 	{ .vendor = _v, .part = _p, .modes = _m, .fixup = _f, }
438 #define SFP_QUIRK_M(_v, _p, _m) SFP_QUIRK(_v, _p, _m, NULL)
439 #define SFP_QUIRK_F(_v, _p, _f) SFP_QUIRK(_v, _p, NULL, _f)
440 
441 static const struct sfp_quirk sfp_quirks[] = {
442 	// Alcatel Lucent G-010S-P can operate at 2500base-X, but incorrectly
443 	// report 2500MBd NRZ in their EEPROM
444 	SFP_QUIRK_M("ALCATELLUCENT", "G010SP", sfp_quirk_2500basex),
445 
446 	// Alcatel Lucent G-010S-A can operate at 2500base-X, but report 3.2GBd
447 	// NRZ in their EEPROM
448 	SFP_QUIRK("ALCATELLUCENT", "3FE46541AA", sfp_quirk_2500basex,
449 		  sfp_fixup_long_startup),
450 
451 	// Fiberstore SFP-10G-T doesn't identify as copper, and uses the
452 	// Rollball protocol to talk to the PHY.
453 	SFP_QUIRK_F("FS", "SFP-10G-T", sfp_fixup_fs_10gt),
454 
455 	SFP_QUIRK_F("HALNy", "HL-GSFP", sfp_fixup_halny_gsfp),
456 
457 	// HG MXPD-483II-F 2.5G supports 2500Base-X, but incorrectly reports
458 	// 2600MBd in their EERPOM
459 	SFP_QUIRK_M("HG GENUINE", "MXPD-483II", sfp_quirk_2500basex),
460 
461 	// Huawei MA5671A can operate at 2500base-X, but report 1.2GBd NRZ in
462 	// their EEPROM
463 	SFP_QUIRK("HUAWEI", "MA5671A", sfp_quirk_2500basex,
464 		  sfp_fixup_ignore_tx_fault),
465 
466 	// Lantech 8330-262D-E can operate at 2500base-X, but incorrectly report
467 	// 2500MBd NRZ in their EEPROM
468 	SFP_QUIRK_M("Lantech", "8330-262D-E", sfp_quirk_2500basex),
469 
470 	SFP_QUIRK_M("UBNT", "UF-INSTANT", sfp_quirk_ubnt_uf_instant),
471 
472 	// Walsun HXSX-ATR[CI]-1 don't identify as copper, and use the
473 	// Rollball protocol to talk to the PHY.
474 	SFP_QUIRK_F("Walsun", "HXSX-ATRC-1", sfp_fixup_fs_10gt),
475 	SFP_QUIRK_F("Walsun", "HXSX-ATRI-1", sfp_fixup_fs_10gt),
476 
477 	SFP_QUIRK_F("OEM", "SFP-10G-T", sfp_fixup_rollball_cc),
478 	SFP_QUIRK_M("OEM", "SFP-2.5G-T", sfp_quirk_oem_2_5g),
479 	SFP_QUIRK_F("OEM", "RTSFP-10", sfp_fixup_rollball_cc),
480 	SFP_QUIRK_F("OEM", "RTSFP-10G", sfp_fixup_rollball_cc),
481 	SFP_QUIRK_F("Turris", "RTSFP-10", sfp_fixup_rollball),
482 	SFP_QUIRK_F("Turris", "RTSFP-10G", sfp_fixup_rollball),
483 };
484 
485 static size_t sfp_strlen(const char *str, size_t maxlen)
486 {
487 	size_t size, i;
488 
489 	/* Trailing characters should be filled with space chars, but
490 	 * some manufacturers can't read SFF-8472 and use NUL.
491 	 */
492 	for (i = 0, size = 0; i < maxlen; i++)
493 		if (str[i] != ' ' && str[i] != '\0')
494 			size = i + 1;
495 
496 	return size;
497 }
498 
499 static bool sfp_match(const char *qs, const char *str, size_t len)
500 {
501 	if (!qs)
502 		return true;
503 	if (strlen(qs) != len)
504 		return false;
505 	return !strncmp(qs, str, len);
506 }
507 
508 static const struct sfp_quirk *sfp_lookup_quirk(const struct sfp_eeprom_id *id)
509 {
510 	const struct sfp_quirk *q;
511 	unsigned int i;
512 	size_t vs, ps;
513 
514 	vs = sfp_strlen(id->base.vendor_name, ARRAY_SIZE(id->base.vendor_name));
515 	ps = sfp_strlen(id->base.vendor_pn, ARRAY_SIZE(id->base.vendor_pn));
516 
517 	for (i = 0, q = sfp_quirks; i < ARRAY_SIZE(sfp_quirks); i++, q++)
518 		if (sfp_match(q->vendor, id->base.vendor_name, vs) &&
519 		    sfp_match(q->part, id->base.vendor_pn, ps))
520 			return q;
521 
522 	return NULL;
523 }
524 
525 static unsigned long poll_jiffies;
526 
527 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
528 {
529 	unsigned int i, state, v;
530 
531 	for (i = state = 0; i < GPIO_MAX; i++) {
532 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
533 			continue;
534 
535 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
536 		if (v)
537 			state |= BIT(i);
538 	}
539 
540 	return state;
541 }
542 
543 static unsigned int sff_gpio_get_state(struct sfp *sfp)
544 {
545 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
546 }
547 
548 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
549 {
550 	unsigned int drive;
551 
552 	if (state & SFP_F_PRESENT)
553 		/* If the module is present, drive the requested signals */
554 		drive = sfp->state_hw_drive;
555 	else
556 		/* Otherwise, let them float to the pull-ups */
557 		drive = 0;
558 
559 	if (sfp->gpio[GPIO_TX_DISABLE]) {
560 		if (drive & SFP_F_TX_DISABLE)
561 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
562 					       state & SFP_F_TX_DISABLE);
563 		else
564 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
565 	}
566 
567 	if (sfp->gpio[GPIO_RS0]) {
568 		if (drive & SFP_F_RS0)
569 			gpiod_direction_output(sfp->gpio[GPIO_RS0],
570 					       state & SFP_F_RS0);
571 		else
572 			gpiod_direction_input(sfp->gpio[GPIO_RS0]);
573 	}
574 
575 	if (sfp->gpio[GPIO_RS1]) {
576 		if (drive & SFP_F_RS1)
577 			gpiod_direction_output(sfp->gpio[GPIO_RS1],
578 					       state & SFP_F_RS1);
579 		else
580 			gpiod_direction_input(sfp->gpio[GPIO_RS1]);
581 	}
582 }
583 
584 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
585 			size_t len)
586 {
587 	struct i2c_msg msgs[2];
588 	u8 bus_addr = a2 ? 0x51 : 0x50;
589 	size_t block_size = sfp->i2c_block_size;
590 	size_t this_len;
591 	int ret;
592 
593 	msgs[0].addr = bus_addr;
594 	msgs[0].flags = 0;
595 	msgs[0].len = 1;
596 	msgs[0].buf = &dev_addr;
597 	msgs[1].addr = bus_addr;
598 	msgs[1].flags = I2C_M_RD;
599 	msgs[1].len = len;
600 	msgs[1].buf = buf;
601 
602 	while (len) {
603 		this_len = len;
604 		if (this_len > block_size)
605 			this_len = block_size;
606 
607 		msgs[1].len = this_len;
608 
609 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
610 		if (ret < 0)
611 			return ret;
612 
613 		if (ret != ARRAY_SIZE(msgs))
614 			break;
615 
616 		msgs[1].buf += this_len;
617 		dev_addr += this_len;
618 		len -= this_len;
619 	}
620 
621 	return msgs[1].buf - (u8 *)buf;
622 }
623 
624 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
625 	size_t len)
626 {
627 	struct i2c_msg msgs[1];
628 	u8 bus_addr = a2 ? 0x51 : 0x50;
629 	int ret;
630 
631 	msgs[0].addr = bus_addr;
632 	msgs[0].flags = 0;
633 	msgs[0].len = 1 + len;
634 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
635 	if (!msgs[0].buf)
636 		return -ENOMEM;
637 
638 	msgs[0].buf[0] = dev_addr;
639 	memcpy(&msgs[0].buf[1], buf, len);
640 
641 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
642 
643 	kfree(msgs[0].buf);
644 
645 	if (ret < 0)
646 		return ret;
647 
648 	return ret == ARRAY_SIZE(msgs) ? len : 0;
649 }
650 
651 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
652 {
653 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
654 		return -EINVAL;
655 
656 	sfp->i2c = i2c;
657 	sfp->read = sfp_i2c_read;
658 	sfp->write = sfp_i2c_write;
659 
660 	return 0;
661 }
662 
663 static int sfp_i2c_mdiobus_create(struct sfp *sfp)
664 {
665 	struct mii_bus *i2c_mii;
666 	int ret;
667 
668 	i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, sfp->mdio_protocol);
669 	if (IS_ERR(i2c_mii))
670 		return PTR_ERR(i2c_mii);
671 
672 	i2c_mii->name = "SFP I2C Bus";
673 	i2c_mii->phy_mask = ~0;
674 
675 	ret = mdiobus_register(i2c_mii);
676 	if (ret < 0) {
677 		mdiobus_free(i2c_mii);
678 		return ret;
679 	}
680 
681 	sfp->i2c_mii = i2c_mii;
682 
683 	return 0;
684 }
685 
686 static void sfp_i2c_mdiobus_destroy(struct sfp *sfp)
687 {
688 	mdiobus_unregister(sfp->i2c_mii);
689 	sfp->i2c_mii = NULL;
690 }
691 
692 /* Interface */
693 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
694 {
695 	return sfp->read(sfp, a2, addr, buf, len);
696 }
697 
698 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
699 {
700 	return sfp->write(sfp, a2, addr, buf, len);
701 }
702 
703 static int sfp_modify_u8(struct sfp *sfp, bool a2, u8 addr, u8 mask, u8 val)
704 {
705 	int ret;
706 	u8 old, v;
707 
708 	ret = sfp_read(sfp, a2, addr, &old, sizeof(old));
709 	if (ret != sizeof(old))
710 		return ret;
711 
712 	v = (old & ~mask) | (val & mask);
713 	if (v == old)
714 		return sizeof(v);
715 
716 	return sfp_write(sfp, a2, addr, &v, sizeof(v));
717 }
718 
719 static unsigned int sfp_soft_get_state(struct sfp *sfp)
720 {
721 	unsigned int state = 0;
722 	u8 status;
723 	int ret;
724 
725 	ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
726 	if (ret == sizeof(status)) {
727 		if (status & SFP_STATUS_RX_LOS)
728 			state |= SFP_F_LOS;
729 		if (status & SFP_STATUS_TX_FAULT)
730 			state |= SFP_F_TX_FAULT;
731 	} else {
732 		dev_err_ratelimited(sfp->dev,
733 				    "failed to read SFP soft status: %pe\n",
734 				    ERR_PTR(ret));
735 		/* Preserve the current state */
736 		state = sfp->state;
737 	}
738 
739 	return state & sfp->state_soft_mask;
740 }
741 
742 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state,
743 			       unsigned int soft)
744 {
745 	u8 mask = 0;
746 	u8 val = 0;
747 
748 	if (soft & SFP_F_TX_DISABLE)
749 		mask |= SFP_STATUS_TX_DISABLE_FORCE;
750 	if (state & SFP_F_TX_DISABLE)
751 		val |= SFP_STATUS_TX_DISABLE_FORCE;
752 
753 	if (soft & SFP_F_RS0)
754 		mask |= SFP_STATUS_RS0_SELECT;
755 	if (state & SFP_F_RS0)
756 		val |= SFP_STATUS_RS0_SELECT;
757 
758 	if (mask)
759 		sfp_modify_u8(sfp, true, SFP_STATUS, mask, val);
760 
761 	val = mask = 0;
762 	if (soft & SFP_F_RS1)
763 		mask |= SFP_EXT_STATUS_RS1_SELECT;
764 	if (state & SFP_F_RS1)
765 		val |= SFP_EXT_STATUS_RS1_SELECT;
766 
767 	if (mask)
768 		sfp_modify_u8(sfp, true, SFP_EXT_STATUS, mask, val);
769 }
770 
771 static void sfp_soft_start_poll(struct sfp *sfp)
772 {
773 	const struct sfp_eeprom_id *id = &sfp->id;
774 	unsigned int mask = 0;
775 
776 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE)
777 		mask |= SFP_F_TX_DISABLE;
778 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT)
779 		mask |= SFP_F_TX_FAULT;
780 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS)
781 		mask |= SFP_F_LOS;
782 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RATE_SELECT)
783 		mask |= sfp->rs_state_mask;
784 
785 	mutex_lock(&sfp->st_mutex);
786 	// Poll the soft state for hardware pins we want to ignore
787 	sfp->state_soft_mask = ~sfp->state_hw_mask & mask;
788 
789 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
790 	    !sfp->need_poll)
791 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
792 	mutex_unlock(&sfp->st_mutex);
793 }
794 
795 static void sfp_soft_stop_poll(struct sfp *sfp)
796 {
797 	mutex_lock(&sfp->st_mutex);
798 	sfp->state_soft_mask = 0;
799 	mutex_unlock(&sfp->st_mutex);
800 }
801 
802 /* sfp_get_state() - must be called with st_mutex held, or in the
803  * initialisation path.
804  */
805 static unsigned int sfp_get_state(struct sfp *sfp)
806 {
807 	unsigned int soft = sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT);
808 	unsigned int state;
809 
810 	state = sfp->get_state(sfp) & sfp->state_hw_mask;
811 	if (state & SFP_F_PRESENT && soft)
812 		state |= sfp_soft_get_state(sfp);
813 
814 	return state;
815 }
816 
817 /* sfp_set_state() - must be called with st_mutex held, or in the
818  * initialisation path.
819  */
820 static void sfp_set_state(struct sfp *sfp, unsigned int state)
821 {
822 	unsigned int soft;
823 
824 	sfp->set_state(sfp, state);
825 
826 	soft = sfp->state_soft_mask & SFP_F_OUTPUTS;
827 	if (state & SFP_F_PRESENT && soft)
828 		sfp_soft_set_state(sfp, state, soft);
829 }
830 
831 static void sfp_mod_state(struct sfp *sfp, unsigned int mask, unsigned int set)
832 {
833 	mutex_lock(&sfp->st_mutex);
834 	sfp->state = (sfp->state & ~mask) | set;
835 	sfp_set_state(sfp, sfp->state);
836 	mutex_unlock(&sfp->st_mutex);
837 }
838 
839 static unsigned int sfp_check(void *buf, size_t len)
840 {
841 	u8 *p, check;
842 
843 	for (p = buf, check = 0; len; p++, len--)
844 		check += *p;
845 
846 	return check;
847 }
848 
849 /* hwmon */
850 #if IS_ENABLED(CONFIG_HWMON)
851 static umode_t sfp_hwmon_is_visible(const void *data,
852 				    enum hwmon_sensor_types type,
853 				    u32 attr, int channel)
854 {
855 	const struct sfp *sfp = data;
856 
857 	switch (type) {
858 	case hwmon_temp:
859 		switch (attr) {
860 		case hwmon_temp_min_alarm:
861 		case hwmon_temp_max_alarm:
862 		case hwmon_temp_lcrit_alarm:
863 		case hwmon_temp_crit_alarm:
864 		case hwmon_temp_min:
865 		case hwmon_temp_max:
866 		case hwmon_temp_lcrit:
867 		case hwmon_temp_crit:
868 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
869 				return 0;
870 			fallthrough;
871 		case hwmon_temp_input:
872 		case hwmon_temp_label:
873 			return 0444;
874 		default:
875 			return 0;
876 		}
877 	case hwmon_in:
878 		switch (attr) {
879 		case hwmon_in_min_alarm:
880 		case hwmon_in_max_alarm:
881 		case hwmon_in_lcrit_alarm:
882 		case hwmon_in_crit_alarm:
883 		case hwmon_in_min:
884 		case hwmon_in_max:
885 		case hwmon_in_lcrit:
886 		case hwmon_in_crit:
887 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
888 				return 0;
889 			fallthrough;
890 		case hwmon_in_input:
891 		case hwmon_in_label:
892 			return 0444;
893 		default:
894 			return 0;
895 		}
896 	case hwmon_curr:
897 		switch (attr) {
898 		case hwmon_curr_min_alarm:
899 		case hwmon_curr_max_alarm:
900 		case hwmon_curr_lcrit_alarm:
901 		case hwmon_curr_crit_alarm:
902 		case hwmon_curr_min:
903 		case hwmon_curr_max:
904 		case hwmon_curr_lcrit:
905 		case hwmon_curr_crit:
906 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
907 				return 0;
908 			fallthrough;
909 		case hwmon_curr_input:
910 		case hwmon_curr_label:
911 			return 0444;
912 		default:
913 			return 0;
914 		}
915 	case hwmon_power:
916 		/* External calibration of receive power requires
917 		 * floating point arithmetic. Doing that in the kernel
918 		 * is not easy, so just skip it. If the module does
919 		 * not require external calibration, we can however
920 		 * show receiver power, since FP is then not needed.
921 		 */
922 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
923 		    channel == 1)
924 			return 0;
925 		switch (attr) {
926 		case hwmon_power_min_alarm:
927 		case hwmon_power_max_alarm:
928 		case hwmon_power_lcrit_alarm:
929 		case hwmon_power_crit_alarm:
930 		case hwmon_power_min:
931 		case hwmon_power_max:
932 		case hwmon_power_lcrit:
933 		case hwmon_power_crit:
934 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
935 				return 0;
936 			fallthrough;
937 		case hwmon_power_input:
938 		case hwmon_power_label:
939 			return 0444;
940 		default:
941 			return 0;
942 		}
943 	default:
944 		return 0;
945 	}
946 }
947 
948 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
949 {
950 	__be16 val;
951 	int err;
952 
953 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
954 	if (err < 0)
955 		return err;
956 
957 	*value = be16_to_cpu(val);
958 
959 	return 0;
960 }
961 
962 static void sfp_hwmon_to_rx_power(long *value)
963 {
964 	*value = DIV_ROUND_CLOSEST(*value, 10);
965 }
966 
967 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
968 				long *value)
969 {
970 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
971 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
972 }
973 
974 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
975 {
976 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
977 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
978 
979 	if (*value >= 0x8000)
980 		*value -= 0x10000;
981 
982 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
983 }
984 
985 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
986 {
987 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
988 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
989 
990 	*value = DIV_ROUND_CLOSEST(*value, 10);
991 }
992 
993 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
994 {
995 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
996 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
997 
998 	*value = DIV_ROUND_CLOSEST(*value, 500);
999 }
1000 
1001 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
1002 {
1003 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
1004 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
1005 
1006 	*value = DIV_ROUND_CLOSEST(*value, 10);
1007 }
1008 
1009 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
1010 {
1011 	int err;
1012 
1013 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1014 	if (err < 0)
1015 		return err;
1016 
1017 	sfp_hwmon_calibrate_temp(sfp, value);
1018 
1019 	return 0;
1020 }
1021 
1022 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
1023 {
1024 	int err;
1025 
1026 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1027 	if (err < 0)
1028 		return err;
1029 
1030 	sfp_hwmon_calibrate_vcc(sfp, value);
1031 
1032 	return 0;
1033 }
1034 
1035 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
1036 {
1037 	int err;
1038 
1039 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1040 	if (err < 0)
1041 		return err;
1042 
1043 	sfp_hwmon_calibrate_bias(sfp, value);
1044 
1045 	return 0;
1046 }
1047 
1048 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
1049 {
1050 	int err;
1051 
1052 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1053 	if (err < 0)
1054 		return err;
1055 
1056 	sfp_hwmon_calibrate_tx_power(sfp, value);
1057 
1058 	return 0;
1059 }
1060 
1061 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
1062 {
1063 	int err;
1064 
1065 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1066 	if (err < 0)
1067 		return err;
1068 
1069 	sfp_hwmon_to_rx_power(value);
1070 
1071 	return 0;
1072 }
1073 
1074 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
1075 {
1076 	u8 status;
1077 	int err;
1078 
1079 	switch (attr) {
1080 	case hwmon_temp_input:
1081 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
1082 
1083 	case hwmon_temp_lcrit:
1084 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
1085 		sfp_hwmon_calibrate_temp(sfp, value);
1086 		return 0;
1087 
1088 	case hwmon_temp_min:
1089 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
1090 		sfp_hwmon_calibrate_temp(sfp, value);
1091 		return 0;
1092 	case hwmon_temp_max:
1093 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
1094 		sfp_hwmon_calibrate_temp(sfp, value);
1095 		return 0;
1096 
1097 	case hwmon_temp_crit:
1098 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
1099 		sfp_hwmon_calibrate_temp(sfp, value);
1100 		return 0;
1101 
1102 	case hwmon_temp_lcrit_alarm:
1103 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1104 		if (err < 0)
1105 			return err;
1106 
1107 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
1108 		return 0;
1109 
1110 	case hwmon_temp_min_alarm:
1111 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1112 		if (err < 0)
1113 			return err;
1114 
1115 		*value = !!(status & SFP_WARN0_TEMP_LOW);
1116 		return 0;
1117 
1118 	case hwmon_temp_max_alarm:
1119 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1120 		if (err < 0)
1121 			return err;
1122 
1123 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
1124 		return 0;
1125 
1126 	case hwmon_temp_crit_alarm:
1127 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1128 		if (err < 0)
1129 			return err;
1130 
1131 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
1132 		return 0;
1133 	default:
1134 		return -EOPNOTSUPP;
1135 	}
1136 
1137 	return -EOPNOTSUPP;
1138 }
1139 
1140 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
1141 {
1142 	u8 status;
1143 	int err;
1144 
1145 	switch (attr) {
1146 	case hwmon_in_input:
1147 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
1148 
1149 	case hwmon_in_lcrit:
1150 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
1151 		sfp_hwmon_calibrate_vcc(sfp, value);
1152 		return 0;
1153 
1154 	case hwmon_in_min:
1155 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
1156 		sfp_hwmon_calibrate_vcc(sfp, value);
1157 		return 0;
1158 
1159 	case hwmon_in_max:
1160 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
1161 		sfp_hwmon_calibrate_vcc(sfp, value);
1162 		return 0;
1163 
1164 	case hwmon_in_crit:
1165 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
1166 		sfp_hwmon_calibrate_vcc(sfp, value);
1167 		return 0;
1168 
1169 	case hwmon_in_lcrit_alarm:
1170 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1171 		if (err < 0)
1172 			return err;
1173 
1174 		*value = !!(status & SFP_ALARM0_VCC_LOW);
1175 		return 0;
1176 
1177 	case hwmon_in_min_alarm:
1178 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1179 		if (err < 0)
1180 			return err;
1181 
1182 		*value = !!(status & SFP_WARN0_VCC_LOW);
1183 		return 0;
1184 
1185 	case hwmon_in_max_alarm:
1186 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1187 		if (err < 0)
1188 			return err;
1189 
1190 		*value = !!(status & SFP_WARN0_VCC_HIGH);
1191 		return 0;
1192 
1193 	case hwmon_in_crit_alarm:
1194 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1195 		if (err < 0)
1196 			return err;
1197 
1198 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
1199 		return 0;
1200 	default:
1201 		return -EOPNOTSUPP;
1202 	}
1203 
1204 	return -EOPNOTSUPP;
1205 }
1206 
1207 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
1208 {
1209 	u8 status;
1210 	int err;
1211 
1212 	switch (attr) {
1213 	case hwmon_curr_input:
1214 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
1215 
1216 	case hwmon_curr_lcrit:
1217 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
1218 		sfp_hwmon_calibrate_bias(sfp, value);
1219 		return 0;
1220 
1221 	case hwmon_curr_min:
1222 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
1223 		sfp_hwmon_calibrate_bias(sfp, value);
1224 		return 0;
1225 
1226 	case hwmon_curr_max:
1227 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
1228 		sfp_hwmon_calibrate_bias(sfp, value);
1229 		return 0;
1230 
1231 	case hwmon_curr_crit:
1232 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
1233 		sfp_hwmon_calibrate_bias(sfp, value);
1234 		return 0;
1235 
1236 	case hwmon_curr_lcrit_alarm:
1237 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1238 		if (err < 0)
1239 			return err;
1240 
1241 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
1242 		return 0;
1243 
1244 	case hwmon_curr_min_alarm:
1245 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1246 		if (err < 0)
1247 			return err;
1248 
1249 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
1250 		return 0;
1251 
1252 	case hwmon_curr_max_alarm:
1253 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1254 		if (err < 0)
1255 			return err;
1256 
1257 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
1258 		return 0;
1259 
1260 	case hwmon_curr_crit_alarm:
1261 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1262 		if (err < 0)
1263 			return err;
1264 
1265 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
1266 		return 0;
1267 	default:
1268 		return -EOPNOTSUPP;
1269 	}
1270 
1271 	return -EOPNOTSUPP;
1272 }
1273 
1274 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
1275 {
1276 	u8 status;
1277 	int err;
1278 
1279 	switch (attr) {
1280 	case hwmon_power_input:
1281 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
1282 
1283 	case hwmon_power_lcrit:
1284 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
1285 		sfp_hwmon_calibrate_tx_power(sfp, value);
1286 		return 0;
1287 
1288 	case hwmon_power_min:
1289 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
1290 		sfp_hwmon_calibrate_tx_power(sfp, value);
1291 		return 0;
1292 
1293 	case hwmon_power_max:
1294 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
1295 		sfp_hwmon_calibrate_tx_power(sfp, value);
1296 		return 0;
1297 
1298 	case hwmon_power_crit:
1299 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
1300 		sfp_hwmon_calibrate_tx_power(sfp, value);
1301 		return 0;
1302 
1303 	case hwmon_power_lcrit_alarm:
1304 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1305 		if (err < 0)
1306 			return err;
1307 
1308 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
1309 		return 0;
1310 
1311 	case hwmon_power_min_alarm:
1312 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1313 		if (err < 0)
1314 			return err;
1315 
1316 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
1317 		return 0;
1318 
1319 	case hwmon_power_max_alarm:
1320 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1321 		if (err < 0)
1322 			return err;
1323 
1324 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1325 		return 0;
1326 
1327 	case hwmon_power_crit_alarm:
1328 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1329 		if (err < 0)
1330 			return err;
1331 
1332 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1333 		return 0;
1334 	default:
1335 		return -EOPNOTSUPP;
1336 	}
1337 
1338 	return -EOPNOTSUPP;
1339 }
1340 
1341 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1342 {
1343 	u8 status;
1344 	int err;
1345 
1346 	switch (attr) {
1347 	case hwmon_power_input:
1348 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1349 
1350 	case hwmon_power_lcrit:
1351 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1352 		sfp_hwmon_to_rx_power(value);
1353 		return 0;
1354 
1355 	case hwmon_power_min:
1356 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1357 		sfp_hwmon_to_rx_power(value);
1358 		return 0;
1359 
1360 	case hwmon_power_max:
1361 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1362 		sfp_hwmon_to_rx_power(value);
1363 		return 0;
1364 
1365 	case hwmon_power_crit:
1366 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1367 		sfp_hwmon_to_rx_power(value);
1368 		return 0;
1369 
1370 	case hwmon_power_lcrit_alarm:
1371 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1372 		if (err < 0)
1373 			return err;
1374 
1375 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1376 		return 0;
1377 
1378 	case hwmon_power_min_alarm:
1379 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1380 		if (err < 0)
1381 			return err;
1382 
1383 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1384 		return 0;
1385 
1386 	case hwmon_power_max_alarm:
1387 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1388 		if (err < 0)
1389 			return err;
1390 
1391 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1392 		return 0;
1393 
1394 	case hwmon_power_crit_alarm:
1395 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1396 		if (err < 0)
1397 			return err;
1398 
1399 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1400 		return 0;
1401 	default:
1402 		return -EOPNOTSUPP;
1403 	}
1404 
1405 	return -EOPNOTSUPP;
1406 }
1407 
1408 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1409 			  u32 attr, int channel, long *value)
1410 {
1411 	struct sfp *sfp = dev_get_drvdata(dev);
1412 
1413 	switch (type) {
1414 	case hwmon_temp:
1415 		return sfp_hwmon_temp(sfp, attr, value);
1416 	case hwmon_in:
1417 		return sfp_hwmon_vcc(sfp, attr, value);
1418 	case hwmon_curr:
1419 		return sfp_hwmon_bias(sfp, attr, value);
1420 	case hwmon_power:
1421 		switch (channel) {
1422 		case 0:
1423 			return sfp_hwmon_tx_power(sfp, attr, value);
1424 		case 1:
1425 			return sfp_hwmon_rx_power(sfp, attr, value);
1426 		default:
1427 			return -EOPNOTSUPP;
1428 		}
1429 	default:
1430 		return -EOPNOTSUPP;
1431 	}
1432 }
1433 
1434 static const char *const sfp_hwmon_power_labels[] = {
1435 	"TX_power",
1436 	"RX_power",
1437 };
1438 
1439 static int sfp_hwmon_read_string(struct device *dev,
1440 				 enum hwmon_sensor_types type,
1441 				 u32 attr, int channel, const char **str)
1442 {
1443 	switch (type) {
1444 	case hwmon_curr:
1445 		switch (attr) {
1446 		case hwmon_curr_label:
1447 			*str = "bias";
1448 			return 0;
1449 		default:
1450 			return -EOPNOTSUPP;
1451 		}
1452 		break;
1453 	case hwmon_temp:
1454 		switch (attr) {
1455 		case hwmon_temp_label:
1456 			*str = "temperature";
1457 			return 0;
1458 		default:
1459 			return -EOPNOTSUPP;
1460 		}
1461 		break;
1462 	case hwmon_in:
1463 		switch (attr) {
1464 		case hwmon_in_label:
1465 			*str = "VCC";
1466 			return 0;
1467 		default:
1468 			return -EOPNOTSUPP;
1469 		}
1470 		break;
1471 	case hwmon_power:
1472 		switch (attr) {
1473 		case hwmon_power_label:
1474 			*str = sfp_hwmon_power_labels[channel];
1475 			return 0;
1476 		default:
1477 			return -EOPNOTSUPP;
1478 		}
1479 		break;
1480 	default:
1481 		return -EOPNOTSUPP;
1482 	}
1483 
1484 	return -EOPNOTSUPP;
1485 }
1486 
1487 static const struct hwmon_ops sfp_hwmon_ops = {
1488 	.is_visible = sfp_hwmon_is_visible,
1489 	.read = sfp_hwmon_read,
1490 	.read_string = sfp_hwmon_read_string,
1491 };
1492 
1493 static const struct hwmon_channel_info * const sfp_hwmon_info[] = {
1494 	HWMON_CHANNEL_INFO(chip,
1495 			   HWMON_C_REGISTER_TZ),
1496 	HWMON_CHANNEL_INFO(in,
1497 			   HWMON_I_INPUT |
1498 			   HWMON_I_MAX | HWMON_I_MIN |
1499 			   HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1500 			   HWMON_I_CRIT | HWMON_I_LCRIT |
1501 			   HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1502 			   HWMON_I_LABEL),
1503 	HWMON_CHANNEL_INFO(temp,
1504 			   HWMON_T_INPUT |
1505 			   HWMON_T_MAX | HWMON_T_MIN |
1506 			   HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1507 			   HWMON_T_CRIT | HWMON_T_LCRIT |
1508 			   HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1509 			   HWMON_T_LABEL),
1510 	HWMON_CHANNEL_INFO(curr,
1511 			   HWMON_C_INPUT |
1512 			   HWMON_C_MAX | HWMON_C_MIN |
1513 			   HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1514 			   HWMON_C_CRIT | HWMON_C_LCRIT |
1515 			   HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1516 			   HWMON_C_LABEL),
1517 	HWMON_CHANNEL_INFO(power,
1518 			   /* Transmit power */
1519 			   HWMON_P_INPUT |
1520 			   HWMON_P_MAX | HWMON_P_MIN |
1521 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1522 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1523 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1524 			   HWMON_P_LABEL,
1525 			   /* Receive power */
1526 			   HWMON_P_INPUT |
1527 			   HWMON_P_MAX | HWMON_P_MIN |
1528 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1529 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1530 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1531 			   HWMON_P_LABEL),
1532 	NULL,
1533 };
1534 
1535 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1536 	.ops = &sfp_hwmon_ops,
1537 	.info = sfp_hwmon_info,
1538 };
1539 
1540 static void sfp_hwmon_probe(struct work_struct *work)
1541 {
1542 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1543 	int err;
1544 
1545 	/* hwmon interface needs to access 16bit registers in atomic way to
1546 	 * guarantee coherency of the diagnostic monitoring data. If it is not
1547 	 * possible to guarantee coherency because EEPROM is broken in such way
1548 	 * that does not support atomic 16bit read operation then we have to
1549 	 * skip registration of hwmon device.
1550 	 */
1551 	if (sfp->i2c_block_size < 2) {
1552 		dev_info(sfp->dev,
1553 			 "skipping hwmon device registration due to broken EEPROM\n");
1554 		dev_info(sfp->dev,
1555 			 "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
1556 		return;
1557 	}
1558 
1559 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1560 	if (err < 0) {
1561 		if (sfp->hwmon_tries--) {
1562 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1563 					 T_PROBE_RETRY_SLOW);
1564 		} else {
1565 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
1566 				 ERR_PTR(err));
1567 		}
1568 		return;
1569 	}
1570 
1571 	sfp->hwmon_name = hwmon_sanitize_name(dev_name(sfp->dev));
1572 	if (IS_ERR(sfp->hwmon_name)) {
1573 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1574 		return;
1575 	}
1576 
1577 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1578 							 sfp->hwmon_name, sfp,
1579 							 &sfp_hwmon_chip_info,
1580 							 NULL);
1581 	if (IS_ERR(sfp->hwmon_dev))
1582 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1583 			PTR_ERR(sfp->hwmon_dev));
1584 }
1585 
1586 static int sfp_hwmon_insert(struct sfp *sfp)
1587 {
1588 	if (sfp->have_a2 && sfp->id.ext.diagmon & SFP_DIAGMON_DDM) {
1589 		mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1590 		sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1591 	}
1592 
1593 	return 0;
1594 }
1595 
1596 static void sfp_hwmon_remove(struct sfp *sfp)
1597 {
1598 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1599 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1600 		hwmon_device_unregister(sfp->hwmon_dev);
1601 		sfp->hwmon_dev = NULL;
1602 		kfree(sfp->hwmon_name);
1603 	}
1604 }
1605 
1606 static int sfp_hwmon_init(struct sfp *sfp)
1607 {
1608 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1609 
1610 	return 0;
1611 }
1612 
1613 static void sfp_hwmon_exit(struct sfp *sfp)
1614 {
1615 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1616 }
1617 #else
1618 static int sfp_hwmon_insert(struct sfp *sfp)
1619 {
1620 	return 0;
1621 }
1622 
1623 static void sfp_hwmon_remove(struct sfp *sfp)
1624 {
1625 }
1626 
1627 static int sfp_hwmon_init(struct sfp *sfp)
1628 {
1629 	return 0;
1630 }
1631 
1632 static void sfp_hwmon_exit(struct sfp *sfp)
1633 {
1634 }
1635 #endif
1636 
1637 /* Helpers */
1638 static void sfp_module_tx_disable(struct sfp *sfp)
1639 {
1640 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1641 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1642 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, SFP_F_TX_DISABLE);
1643 }
1644 
1645 static void sfp_module_tx_enable(struct sfp *sfp)
1646 {
1647 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1648 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1649 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, 0);
1650 }
1651 
1652 #if IS_ENABLED(CONFIG_DEBUG_FS)
1653 static int sfp_debug_state_show(struct seq_file *s, void *data)
1654 {
1655 	struct sfp *sfp = s->private;
1656 
1657 	seq_printf(s, "Module state: %s\n",
1658 		   mod_state_to_str(sfp->sm_mod_state));
1659 	seq_printf(s, "Module probe attempts: %d %d\n",
1660 		   R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
1661 		   R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
1662 	seq_printf(s, "Device state: %s\n",
1663 		   dev_state_to_str(sfp->sm_dev_state));
1664 	seq_printf(s, "Main state: %s\n",
1665 		   sm_state_to_str(sfp->sm_state));
1666 	seq_printf(s, "Fault recovery remaining retries: %d\n",
1667 		   sfp->sm_fault_retries);
1668 	seq_printf(s, "PHY probe remaining retries: %d\n",
1669 		   sfp->sm_phy_retries);
1670 	seq_printf(s, "Signalling rate: %u kBd\n", sfp->rate_kbd);
1671 	seq_printf(s, "Rate select threshold: %u kBd\n",
1672 		   sfp->rs_threshold_kbd);
1673 	seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
1674 	seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
1675 	seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
1676 	seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
1677 	seq_printf(s, "rs0: %d\n", !!(sfp->state & SFP_F_RS0));
1678 	seq_printf(s, "rs1: %d\n", !!(sfp->state & SFP_F_RS1));
1679 	return 0;
1680 }
1681 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
1682 
1683 static void sfp_debugfs_init(struct sfp *sfp)
1684 {
1685 	sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
1686 
1687 	debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
1688 			    &sfp_debug_state_fops);
1689 }
1690 
1691 static void sfp_debugfs_exit(struct sfp *sfp)
1692 {
1693 	debugfs_remove_recursive(sfp->debugfs_dir);
1694 }
1695 #else
1696 static void sfp_debugfs_init(struct sfp *sfp)
1697 {
1698 }
1699 
1700 static void sfp_debugfs_exit(struct sfp *sfp)
1701 {
1702 }
1703 #endif
1704 
1705 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1706 {
1707 	unsigned int state;
1708 
1709 	mutex_lock(&sfp->st_mutex);
1710 	state = sfp->state;
1711 	if (!(state & SFP_F_TX_DISABLE)) {
1712 		sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1713 
1714 		udelay(T_RESET_US);
1715 
1716 		sfp_set_state(sfp, state);
1717 	}
1718 	mutex_unlock(&sfp->st_mutex);
1719 }
1720 
1721 /* SFP state machine */
1722 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1723 {
1724 	if (timeout)
1725 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1726 				 timeout);
1727 	else
1728 		cancel_delayed_work(&sfp->timeout);
1729 }
1730 
1731 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1732 			unsigned int timeout)
1733 {
1734 	sfp->sm_state = state;
1735 	sfp_sm_set_timer(sfp, timeout);
1736 }
1737 
1738 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1739 			    unsigned int timeout)
1740 {
1741 	sfp->sm_mod_state = state;
1742 	sfp_sm_set_timer(sfp, timeout);
1743 }
1744 
1745 static void sfp_sm_phy_detach(struct sfp *sfp)
1746 {
1747 	sfp_remove_phy(sfp->sfp_bus);
1748 	phy_device_remove(sfp->mod_phy);
1749 	phy_device_free(sfp->mod_phy);
1750 	sfp->mod_phy = NULL;
1751 }
1752 
1753 static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
1754 {
1755 	struct phy_device *phy;
1756 	int err;
1757 
1758 	phy = get_phy_device(sfp->i2c_mii, addr, is_c45);
1759 	if (phy == ERR_PTR(-ENODEV))
1760 		return PTR_ERR(phy);
1761 	if (IS_ERR(phy)) {
1762 		dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
1763 		return PTR_ERR(phy);
1764 	}
1765 
1766 	/* Mark this PHY as being on a SFP module */
1767 	phy->is_on_sfp_module = true;
1768 
1769 	err = phy_device_register(phy);
1770 	if (err) {
1771 		phy_device_free(phy);
1772 		dev_err(sfp->dev, "phy_device_register failed: %pe\n",
1773 			ERR_PTR(err));
1774 		return err;
1775 	}
1776 
1777 	err = sfp_add_phy(sfp->sfp_bus, phy);
1778 	if (err) {
1779 		phy_device_remove(phy);
1780 		phy_device_free(phy);
1781 		dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
1782 		return err;
1783 	}
1784 
1785 	sfp->mod_phy = phy;
1786 
1787 	return 0;
1788 }
1789 
1790 static void sfp_sm_link_up(struct sfp *sfp)
1791 {
1792 	sfp_link_up(sfp->sfp_bus);
1793 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1794 }
1795 
1796 static void sfp_sm_link_down(struct sfp *sfp)
1797 {
1798 	sfp_link_down(sfp->sfp_bus);
1799 }
1800 
1801 static void sfp_sm_link_check_los(struct sfp *sfp)
1802 {
1803 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1804 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1805 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1806 	bool los = false;
1807 
1808 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1809 	 * are set, we assume that no LOS signal is available. If both are
1810 	 * set, we assume LOS is not implemented (and is meaningless.)
1811 	 */
1812 	if (los_options == los_inverted)
1813 		los = !(sfp->state & SFP_F_LOS);
1814 	else if (los_options == los_normal)
1815 		los = !!(sfp->state & SFP_F_LOS);
1816 
1817 	if (los)
1818 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1819 	else
1820 		sfp_sm_link_up(sfp);
1821 }
1822 
1823 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1824 {
1825 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1826 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1827 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1828 
1829 	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
1830 	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
1831 }
1832 
1833 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1834 {
1835 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1836 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1837 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1838 
1839 	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
1840 	       (los_options == los_normal && event == SFP_E_LOS_LOW);
1841 }
1842 
1843 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1844 {
1845 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
1846 		dev_err(sfp->dev,
1847 			"module persistently indicates fault, disabling\n");
1848 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1849 	} else {
1850 		if (warn)
1851 			dev_err(sfp->dev, "module transmit fault indicated\n");
1852 
1853 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1854 	}
1855 }
1856 
1857 static int sfp_sm_add_mdio_bus(struct sfp *sfp)
1858 {
1859 	if (sfp->mdio_protocol != MDIO_I2C_NONE)
1860 		return sfp_i2c_mdiobus_create(sfp);
1861 
1862 	return 0;
1863 }
1864 
1865 /* Probe a SFP for a PHY device if the module supports copper - the PHY
1866  * normally sits at I2C bus address 0x56, and may either be a clause 22
1867  * or clause 45 PHY.
1868  *
1869  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
1870  * negotiation enabled, but some may be in 1000base-X - which is for the
1871  * PHY driver to determine.
1872  *
1873  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
1874  * mode according to the negotiated line speed.
1875  */
1876 static int sfp_sm_probe_for_phy(struct sfp *sfp)
1877 {
1878 	int err = 0;
1879 
1880 	switch (sfp->mdio_protocol) {
1881 	case MDIO_I2C_NONE:
1882 		break;
1883 
1884 	case MDIO_I2C_MARVELL_C22:
1885 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, false);
1886 		break;
1887 
1888 	case MDIO_I2C_C45:
1889 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, true);
1890 		break;
1891 
1892 	case MDIO_I2C_ROLLBALL:
1893 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR_ROLLBALL, true);
1894 		break;
1895 	}
1896 
1897 	return err;
1898 }
1899 
1900 static int sfp_module_parse_power(struct sfp *sfp)
1901 {
1902 	u32 power_mW = 1000;
1903 	bool supports_a2;
1904 
1905 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
1906 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1907 		power_mW = 1500;
1908 	/* Added in Rev 11.9, but there is no compliance code for this */
1909 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV11_4 &&
1910 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1911 		power_mW = 2000;
1912 
1913 	/* Power level 1 modules (max. 1W) are always supported. */
1914 	if (power_mW <= 1000) {
1915 		sfp->module_power_mW = power_mW;
1916 		return 0;
1917 	}
1918 
1919 	supports_a2 = sfp->id.ext.sff8472_compliance !=
1920 				SFP_SFF8472_COMPLIANCE_NONE ||
1921 		      sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
1922 
1923 	if (power_mW > sfp->max_power_mW) {
1924 		/* Module power specification exceeds the allowed maximum. */
1925 		if (!supports_a2) {
1926 			/* The module appears not to implement bus address
1927 			 * 0xa2, so assume that the module powers up in the
1928 			 * indicated mode.
1929 			 */
1930 			dev_err(sfp->dev,
1931 				"Host does not support %u.%uW modules\n",
1932 				power_mW / 1000, (power_mW / 100) % 10);
1933 			return -EINVAL;
1934 		} else {
1935 			dev_warn(sfp->dev,
1936 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1937 				 power_mW / 1000, (power_mW / 100) % 10);
1938 			return 0;
1939 		}
1940 	}
1941 
1942 	if (!supports_a2) {
1943 		/* The module power level is below the host maximum and the
1944 		 * module appears not to implement bus address 0xa2, so assume
1945 		 * that the module powers up in the indicated mode.
1946 		 */
1947 		return 0;
1948 	}
1949 
1950 	/* If the module requires a higher power mode, but also requires
1951 	 * an address change sequence, warn the user that the module may
1952 	 * not be functional.
1953 	 */
1954 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
1955 		dev_warn(sfp->dev,
1956 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1957 			 power_mW / 1000, (power_mW / 100) % 10);
1958 		return 0;
1959 	}
1960 
1961 	sfp->module_power_mW = power_mW;
1962 
1963 	return 0;
1964 }
1965 
1966 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1967 {
1968 	int err;
1969 
1970 	err = sfp_modify_u8(sfp, true, SFP_EXT_STATUS,
1971 			    SFP_EXT_STATUS_PWRLVL_SELECT,
1972 			    enable ? SFP_EXT_STATUS_PWRLVL_SELECT : 0);
1973 	if (err != sizeof(u8)) {
1974 		dev_err(sfp->dev, "failed to %sable high power: %pe\n",
1975 			enable ? "en" : "dis", ERR_PTR(err));
1976 		return -EAGAIN;
1977 	}
1978 
1979 	if (enable)
1980 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
1981 			 sfp->module_power_mW / 1000,
1982 			 (sfp->module_power_mW / 100) % 10);
1983 
1984 	return 0;
1985 }
1986 
1987 static void sfp_module_parse_rate_select(struct sfp *sfp)
1988 {
1989 	u8 rate_id;
1990 
1991 	sfp->rs_threshold_kbd = 0;
1992 	sfp->rs_state_mask = 0;
1993 
1994 	if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_RATE_SELECT)))
1995 		/* No support for RateSelect */
1996 		return;
1997 
1998 	/* Default to INF-8074 RateSelect operation. The signalling threshold
1999 	 * rate is not well specified, so always select "Full Bandwidth", but
2000 	 * SFF-8079 reveals that it is understood that RS0 will be low for
2001 	 * 1.0625Gb/s and high for 2.125Gb/s. Choose a value half-way between.
2002 	 * This method exists prior to SFF-8472.
2003 	 */
2004 	sfp->rs_state_mask = SFP_F_RS0;
2005 	sfp->rs_threshold_kbd = 1594;
2006 
2007 	/* Parse the rate identifier, which is complicated due to history:
2008 	 * SFF-8472 rev 9.5 marks this field as reserved.
2009 	 * SFF-8079 references SFF-8472 rev 9.5 and defines bit 0. SFF-8472
2010 	 *  compliance is not required.
2011 	 * SFF-8472 rev 10.2 defines this field using values 0..4
2012 	 * SFF-8472 rev 11.0 redefines this field with bit 0 for SFF-8079
2013 	 * and even values.
2014 	 */
2015 	rate_id = sfp->id.base.rate_id;
2016 	if (rate_id == 0)
2017 		/* Unspecified */
2018 		return;
2019 
2020 	/* SFF-8472 rev 10.0..10.4 did not account for SFF-8079 using bit 0,
2021 	 * and allocated value 3 to SFF-8431 independent tx/rx rate select.
2022 	 * Convert this to a SFF-8472 rev 11.0 rate identifier.
2023 	 */
2024 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
2025 	    sfp->id.ext.sff8472_compliance < SFP_SFF8472_COMPLIANCE_REV11_0 &&
2026 	    rate_id == 3)
2027 		rate_id = SFF_RID_8431;
2028 
2029 	if (rate_id & SFF_RID_8079) {
2030 		/* SFF-8079 RateSelect / Application Select in conjunction with
2031 		 * SFF-8472 rev 9.5. SFF-8079 defines rate_id as a bitfield
2032 		 * with only bit 0 used, which takes precedence over SFF-8472.
2033 		 */
2034 		if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_APP_SELECT_SFF8079)) {
2035 			/* SFF-8079 Part 1 - rate selection between Fibre
2036 			 * Channel 1.0625/2.125/4.25 Gbd modes. Note that RS0
2037 			 * is high for 2125, so we have to subtract 1 to
2038 			 * include it.
2039 			 */
2040 			sfp->rs_threshold_kbd = 2125 - 1;
2041 			sfp->rs_state_mask = SFP_F_RS0;
2042 		}
2043 		return;
2044 	}
2045 
2046 	/* SFF-8472 rev 9.5 does not define the rate identifier */
2047 	if (sfp->id.ext.sff8472_compliance <= SFP_SFF8472_COMPLIANCE_REV9_5)
2048 		return;
2049 
2050 	/* SFF-8472 rev 11.0 defines rate_id as a numerical value which will
2051 	 * always have bit 0 clear due to SFF-8079's bitfield usage of rate_id.
2052 	 */
2053 	switch (rate_id) {
2054 	case SFF_RID_8431_RX_ONLY:
2055 		sfp->rs_threshold_kbd = 4250;
2056 		sfp->rs_state_mask = SFP_F_RS0;
2057 		break;
2058 
2059 	case SFF_RID_8431_TX_ONLY:
2060 		sfp->rs_threshold_kbd = 4250;
2061 		sfp->rs_state_mask = SFP_F_RS1;
2062 		break;
2063 
2064 	case SFF_RID_8431:
2065 		sfp->rs_threshold_kbd = 4250;
2066 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2067 		break;
2068 
2069 	case SFF_RID_10G8G:
2070 		sfp->rs_threshold_kbd = 9000;
2071 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2072 		break;
2073 	}
2074 }
2075 
2076 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
2077  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
2078  * not support multibyte reads from the EEPROM. Each multi-byte read
2079  * operation returns just one byte of EEPROM followed by zeros. There is
2080  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
2081  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
2082  * name and vendor id into EEPROM, so there is even no way to detect if
2083  * module is V-SOL V2801F. Therefore check for those zeros in the read
2084  * data and then based on check switch to reading EEPROM to one byte
2085  * at a time.
2086  */
2087 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
2088 {
2089 	size_t i, block_size = sfp->i2c_block_size;
2090 
2091 	/* Already using byte IO */
2092 	if (block_size == 1)
2093 		return false;
2094 
2095 	for (i = 1; i < len; i += block_size) {
2096 		if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
2097 			return false;
2098 	}
2099 	return true;
2100 }
2101 
2102 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
2103 {
2104 	u8 check;
2105 	int err;
2106 
2107 	if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
2108 	    id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
2109 	    id->base.connector != SFF8024_CONNECTOR_LC) {
2110 		dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
2111 		id->base.phys_id = SFF8024_ID_SFF_8472;
2112 		id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
2113 		id->base.connector = SFF8024_CONNECTOR_LC;
2114 		err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
2115 		if (err != 3) {
2116 			dev_err(sfp->dev,
2117 				"Failed to rewrite module EEPROM: %pe\n",
2118 				ERR_PTR(err));
2119 			return err;
2120 		}
2121 
2122 		/* Cotsworks modules have been found to require a delay between write operations. */
2123 		mdelay(50);
2124 
2125 		/* Update base structure checksum */
2126 		check = sfp_check(&id->base, sizeof(id->base) - 1);
2127 		err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
2128 		if (err != 1) {
2129 			dev_err(sfp->dev,
2130 				"Failed to update base structure checksum in fiber module EEPROM: %pe\n",
2131 				ERR_PTR(err));
2132 			return err;
2133 		}
2134 	}
2135 	return 0;
2136 }
2137 
2138 static int sfp_module_parse_sff8472(struct sfp *sfp)
2139 {
2140 	/* If the module requires address swap mode, warn about it */
2141 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
2142 		dev_warn(sfp->dev,
2143 			 "module address swap to access page 0xA2 is not supported.\n");
2144 	else
2145 		sfp->have_a2 = true;
2146 
2147 	return 0;
2148 }
2149 
2150 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
2151 {
2152 	/* SFP module inserted - read I2C data */
2153 	struct sfp_eeprom_id id;
2154 	bool cotsworks_sfbg;
2155 	unsigned int mask;
2156 	bool cotsworks;
2157 	u8 check;
2158 	int ret;
2159 
2160 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2161 
2162 	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2163 	if (ret < 0) {
2164 		if (report)
2165 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2166 				ERR_PTR(ret));
2167 		return -EAGAIN;
2168 	}
2169 
2170 	if (ret != sizeof(id.base)) {
2171 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2172 		return -EAGAIN;
2173 	}
2174 
2175 	/* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
2176 	 * address 0x51 is just one byte at a time. Also SFF-8472 requires
2177 	 * that EEPROM supports atomic 16bit read operation for diagnostic
2178 	 * fields, so do not switch to one byte reading at a time unless it
2179 	 * is really required and we have no other option.
2180 	 */
2181 	if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
2182 		dev_info(sfp->dev,
2183 			 "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
2184 		dev_info(sfp->dev,
2185 			 "Switching to reading EEPROM to one byte at a time\n");
2186 		sfp->i2c_block_size = 1;
2187 
2188 		ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2189 		if (ret < 0) {
2190 			if (report)
2191 				dev_err(sfp->dev,
2192 					"failed to read EEPROM: %pe\n",
2193 					ERR_PTR(ret));
2194 			return -EAGAIN;
2195 		}
2196 
2197 		if (ret != sizeof(id.base)) {
2198 			dev_err(sfp->dev, "EEPROM short read: %pe\n",
2199 				ERR_PTR(ret));
2200 			return -EAGAIN;
2201 		}
2202 	}
2203 
2204 	/* Cotsworks do not seem to update the checksums when they
2205 	 * do the final programming with the final module part number,
2206 	 * serial number and date code.
2207 	 */
2208 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
2209 	cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
2210 
2211 	/* Cotsworks SFF module EEPROM do not always have valid phys_id,
2212 	 * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
2213 	 * Cotsworks PN matches and bytes are not correct.
2214 	 */
2215 	if (cotsworks && cotsworks_sfbg) {
2216 		ret = sfp_cotsworks_fixup_check(sfp, &id);
2217 		if (ret < 0)
2218 			return ret;
2219 	}
2220 
2221 	/* Validate the checksum over the base structure */
2222 	check = sfp_check(&id.base, sizeof(id.base) - 1);
2223 	if (check != id.base.cc_base) {
2224 		if (cotsworks) {
2225 			dev_warn(sfp->dev,
2226 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
2227 				 check, id.base.cc_base);
2228 		} else {
2229 			dev_err(sfp->dev,
2230 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
2231 				check, id.base.cc_base);
2232 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2233 				       16, 1, &id, sizeof(id), true);
2234 			return -EINVAL;
2235 		}
2236 	}
2237 
2238 	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
2239 	if (ret < 0) {
2240 		if (report)
2241 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2242 				ERR_PTR(ret));
2243 		return -EAGAIN;
2244 	}
2245 
2246 	if (ret != sizeof(id.ext)) {
2247 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2248 		return -EAGAIN;
2249 	}
2250 
2251 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
2252 	if (check != id.ext.cc_ext) {
2253 		if (cotsworks) {
2254 			dev_warn(sfp->dev,
2255 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
2256 				 check, id.ext.cc_ext);
2257 		} else {
2258 			dev_err(sfp->dev,
2259 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
2260 				check, id.ext.cc_ext);
2261 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2262 				       16, 1, &id, sizeof(id), true);
2263 			memset(&id.ext, 0, sizeof(id.ext));
2264 		}
2265 	}
2266 
2267 	sfp->id = id;
2268 
2269 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
2270 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
2271 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
2272 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
2273 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
2274 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
2275 
2276 	/* Check whether we support this module */
2277 	if (!sfp->type->module_supported(&id)) {
2278 		dev_err(sfp->dev,
2279 			"module is not supported - phys id 0x%02x 0x%02x\n",
2280 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
2281 		return -EINVAL;
2282 	}
2283 
2284 	if (sfp->id.ext.sff8472_compliance != SFP_SFF8472_COMPLIANCE_NONE) {
2285 		ret = sfp_module_parse_sff8472(sfp);
2286 		if (ret < 0)
2287 			return ret;
2288 	}
2289 
2290 	/* Parse the module power requirement */
2291 	ret = sfp_module_parse_power(sfp);
2292 	if (ret < 0)
2293 		return ret;
2294 
2295 	sfp_module_parse_rate_select(sfp);
2296 
2297 	mask = SFP_F_PRESENT;
2298 	if (sfp->gpio[GPIO_TX_DISABLE])
2299 		mask |= SFP_F_TX_DISABLE;
2300 	if (sfp->gpio[GPIO_TX_FAULT])
2301 		mask |= SFP_F_TX_FAULT;
2302 	if (sfp->gpio[GPIO_LOS])
2303 		mask |= SFP_F_LOS;
2304 	if (sfp->gpio[GPIO_RS0])
2305 		mask |= SFP_F_RS0;
2306 	if (sfp->gpio[GPIO_RS1])
2307 		mask |= SFP_F_RS1;
2308 
2309 	sfp->module_t_start_up = T_START_UP;
2310 	sfp->module_t_wait = T_WAIT;
2311 
2312 	sfp->tx_fault_ignore = false;
2313 
2314 	if (sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SFI ||
2315 	    sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SR ||
2316 	    sfp->id.base.extended_cc == SFF8024_ECC_5GBASE_T ||
2317 	    sfp->id.base.extended_cc == SFF8024_ECC_2_5GBASE_T)
2318 		sfp->mdio_protocol = MDIO_I2C_C45;
2319 	else if (sfp->id.base.e1000_base_t)
2320 		sfp->mdio_protocol = MDIO_I2C_MARVELL_C22;
2321 	else
2322 		sfp->mdio_protocol = MDIO_I2C_NONE;
2323 
2324 	sfp->quirk = sfp_lookup_quirk(&id);
2325 
2326 	mutex_lock(&sfp->st_mutex);
2327 	/* Initialise state bits to use from hardware */
2328 	sfp->state_hw_mask = mask;
2329 
2330 	/* We want to drive the rate select pins that the module is using */
2331 	sfp->state_hw_drive |= sfp->rs_state_mask;
2332 
2333 	if (sfp->quirk && sfp->quirk->fixup)
2334 		sfp->quirk->fixup(sfp);
2335 	mutex_unlock(&sfp->st_mutex);
2336 
2337 	return 0;
2338 }
2339 
2340 static void sfp_sm_mod_remove(struct sfp *sfp)
2341 {
2342 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
2343 		sfp_module_remove(sfp->sfp_bus);
2344 
2345 	sfp_hwmon_remove(sfp);
2346 
2347 	memset(&sfp->id, 0, sizeof(sfp->id));
2348 	sfp->module_power_mW = 0;
2349 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
2350 	sfp->have_a2 = false;
2351 
2352 	dev_info(sfp->dev, "module removed\n");
2353 }
2354 
2355 /* This state machine tracks the upstream's state */
2356 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
2357 {
2358 	switch (sfp->sm_dev_state) {
2359 	default:
2360 		if (event == SFP_E_DEV_ATTACH)
2361 			sfp->sm_dev_state = SFP_DEV_DOWN;
2362 		break;
2363 
2364 	case SFP_DEV_DOWN:
2365 		if (event == SFP_E_DEV_DETACH)
2366 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2367 		else if (event == SFP_E_DEV_UP)
2368 			sfp->sm_dev_state = SFP_DEV_UP;
2369 		break;
2370 
2371 	case SFP_DEV_UP:
2372 		if (event == SFP_E_DEV_DETACH)
2373 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2374 		else if (event == SFP_E_DEV_DOWN)
2375 			sfp->sm_dev_state = SFP_DEV_DOWN;
2376 		break;
2377 	}
2378 }
2379 
2380 /* This state machine tracks the insert/remove state of the module, probes
2381  * the on-board EEPROM, and sets up the power level.
2382  */
2383 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
2384 {
2385 	int err;
2386 
2387 	/* Handle remove event globally, it resets this state machine */
2388 	if (event == SFP_E_REMOVE) {
2389 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
2390 			sfp_sm_mod_remove(sfp);
2391 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
2392 		return;
2393 	}
2394 
2395 	/* Handle device detach globally */
2396 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
2397 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
2398 		if (sfp->module_power_mW > 1000 &&
2399 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
2400 			sfp_sm_mod_hpower(sfp, false);
2401 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2402 		return;
2403 	}
2404 
2405 	switch (sfp->sm_mod_state) {
2406 	default:
2407 		if (event == SFP_E_INSERT) {
2408 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
2409 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
2410 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
2411 		}
2412 		break;
2413 
2414 	case SFP_MOD_PROBE:
2415 		/* Wait for T_PROBE_INIT to time out */
2416 		if (event != SFP_E_TIMEOUT)
2417 			break;
2418 
2419 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
2420 		if (err == -EAGAIN) {
2421 			if (sfp->sm_mod_tries_init &&
2422 			   --sfp->sm_mod_tries_init) {
2423 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2424 				break;
2425 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
2426 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
2427 					dev_warn(sfp->dev,
2428 						 "please wait, module slow to respond\n");
2429 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
2430 				break;
2431 			}
2432 		}
2433 		if (err < 0) {
2434 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2435 			break;
2436 		}
2437 
2438 		/* Force a poll to re-read the hardware signal state after
2439 		 * sfp_sm_mod_probe() changed state_hw_mask.
2440 		 */
2441 		mod_delayed_work(system_wq, &sfp->poll, 1);
2442 
2443 		err = sfp_hwmon_insert(sfp);
2444 		if (err)
2445 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
2446 				 ERR_PTR(err));
2447 
2448 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2449 		fallthrough;
2450 	case SFP_MOD_WAITDEV:
2451 		/* Ensure that the device is attached before proceeding */
2452 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
2453 			break;
2454 
2455 		/* Report the module insertion to the upstream device */
2456 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id,
2457 					sfp->quirk);
2458 		if (err < 0) {
2459 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2460 			break;
2461 		}
2462 
2463 		/* If this is a power level 1 module, we are done */
2464 		if (sfp->module_power_mW <= 1000)
2465 			goto insert;
2466 
2467 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
2468 		fallthrough;
2469 	case SFP_MOD_HPOWER:
2470 		/* Enable high power mode */
2471 		err = sfp_sm_mod_hpower(sfp, true);
2472 		if (err < 0) {
2473 			if (err != -EAGAIN) {
2474 				sfp_module_remove(sfp->sfp_bus);
2475 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2476 			} else {
2477 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2478 			}
2479 			break;
2480 		}
2481 
2482 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
2483 		break;
2484 
2485 	case SFP_MOD_WAITPWR:
2486 		/* Wait for T_HPOWER_LEVEL to time out */
2487 		if (event != SFP_E_TIMEOUT)
2488 			break;
2489 
2490 	insert:
2491 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
2492 		break;
2493 
2494 	case SFP_MOD_PRESENT:
2495 	case SFP_MOD_ERROR:
2496 		break;
2497 	}
2498 }
2499 
2500 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
2501 {
2502 	unsigned long timeout;
2503 	int ret;
2504 
2505 	/* Some events are global */
2506 	if (sfp->sm_state != SFP_S_DOWN &&
2507 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2508 	     sfp->sm_dev_state != SFP_DEV_UP)) {
2509 		if (sfp->sm_state == SFP_S_LINK_UP &&
2510 		    sfp->sm_dev_state == SFP_DEV_UP)
2511 			sfp_sm_link_down(sfp);
2512 		if (sfp->sm_state > SFP_S_INIT)
2513 			sfp_module_stop(sfp->sfp_bus);
2514 		if (sfp->mod_phy)
2515 			sfp_sm_phy_detach(sfp);
2516 		if (sfp->i2c_mii)
2517 			sfp_i2c_mdiobus_destroy(sfp);
2518 		sfp_module_tx_disable(sfp);
2519 		sfp_soft_stop_poll(sfp);
2520 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
2521 		return;
2522 	}
2523 
2524 	/* The main state machine */
2525 	switch (sfp->sm_state) {
2526 	case SFP_S_DOWN:
2527 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2528 		    sfp->sm_dev_state != SFP_DEV_UP)
2529 			break;
2530 
2531 		/* Only use the soft state bits if we have access to the A2h
2532 		 * memory, which implies that we have some level of SFF-8472
2533 		 * compliance.
2534 		 */
2535 		if (sfp->have_a2)
2536 			sfp_soft_start_poll(sfp);
2537 
2538 		sfp_module_tx_enable(sfp);
2539 
2540 		/* Initialise the fault clearance retries */
2541 		sfp->sm_fault_retries = N_FAULT_INIT;
2542 
2543 		/* We need to check the TX_FAULT state, which is not defined
2544 		 * while TX_DISABLE is asserted. The earliest we want to do
2545 		 * anything (such as probe for a PHY) is 50ms (or more on
2546 		 * specific modules).
2547 		 */
2548 		sfp_sm_next(sfp, SFP_S_WAIT, sfp->module_t_wait);
2549 		break;
2550 
2551 	case SFP_S_WAIT:
2552 		if (event != SFP_E_TIMEOUT)
2553 			break;
2554 
2555 		if (sfp->state & SFP_F_TX_FAULT) {
2556 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
2557 			 * from the TX_DISABLE deassertion for the module to
2558 			 * initialise, which is indicated by TX_FAULT
2559 			 * deasserting.
2560 			 */
2561 			timeout = sfp->module_t_start_up;
2562 			if (timeout > sfp->module_t_wait)
2563 				timeout -= sfp->module_t_wait;
2564 			else
2565 				timeout = 1;
2566 
2567 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
2568 		} else {
2569 			/* TX_FAULT is not asserted, assume the module has
2570 			 * finished initialising.
2571 			 */
2572 			goto init_done;
2573 		}
2574 		break;
2575 
2576 	case SFP_S_INIT:
2577 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2578 			/* TX_FAULT is still asserted after t_init
2579 			 * or t_start_up, so assume there is a fault.
2580 			 */
2581 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
2582 				     sfp->sm_fault_retries == N_FAULT_INIT);
2583 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2584 	init_done:
2585 			/* Create mdiobus and start trying for PHY */
2586 			ret = sfp_sm_add_mdio_bus(sfp);
2587 			if (ret < 0) {
2588 				sfp_sm_next(sfp, SFP_S_FAIL, 0);
2589 				break;
2590 			}
2591 			sfp->sm_phy_retries = R_PHY_RETRY;
2592 			goto phy_probe;
2593 		}
2594 		break;
2595 
2596 	case SFP_S_INIT_PHY:
2597 		if (event != SFP_E_TIMEOUT)
2598 			break;
2599 	phy_probe:
2600 		/* TX_FAULT deasserted or we timed out with TX_FAULT
2601 		 * clear.  Probe for the PHY and check the LOS state.
2602 		 */
2603 		ret = sfp_sm_probe_for_phy(sfp);
2604 		if (ret == -ENODEV) {
2605 			if (--sfp->sm_phy_retries) {
2606 				sfp_sm_next(sfp, SFP_S_INIT_PHY, T_PHY_RETRY);
2607 				break;
2608 			} else {
2609 				dev_info(sfp->dev, "no PHY detected\n");
2610 			}
2611 		} else if (ret) {
2612 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2613 			break;
2614 		}
2615 		if (sfp_module_start(sfp->sfp_bus)) {
2616 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2617 			break;
2618 		}
2619 		sfp_sm_link_check_los(sfp);
2620 
2621 		/* Reset the fault retry count */
2622 		sfp->sm_fault_retries = N_FAULT;
2623 		break;
2624 
2625 	case SFP_S_INIT_TX_FAULT:
2626 		if (event == SFP_E_TIMEOUT) {
2627 			sfp_module_tx_fault_reset(sfp);
2628 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
2629 		}
2630 		break;
2631 
2632 	case SFP_S_WAIT_LOS:
2633 		if (event == SFP_E_TX_FAULT)
2634 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2635 		else if (sfp_los_event_inactive(sfp, event))
2636 			sfp_sm_link_up(sfp);
2637 		break;
2638 
2639 	case SFP_S_LINK_UP:
2640 		if (event == SFP_E_TX_FAULT) {
2641 			sfp_sm_link_down(sfp);
2642 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2643 		} else if (sfp_los_event_active(sfp, event)) {
2644 			sfp_sm_link_down(sfp);
2645 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2646 		}
2647 		break;
2648 
2649 	case SFP_S_TX_FAULT:
2650 		if (event == SFP_E_TIMEOUT) {
2651 			sfp_module_tx_fault_reset(sfp);
2652 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2653 		}
2654 		break;
2655 
2656 	case SFP_S_REINIT:
2657 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2658 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2659 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2660 			dev_info(sfp->dev, "module transmit fault recovered\n");
2661 			sfp_sm_link_check_los(sfp);
2662 		}
2663 		break;
2664 
2665 	case SFP_S_TX_DISABLE:
2666 		break;
2667 	}
2668 }
2669 
2670 static void __sfp_sm_event(struct sfp *sfp, unsigned int event)
2671 {
2672 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
2673 		mod_state_to_str(sfp->sm_mod_state),
2674 		dev_state_to_str(sfp->sm_dev_state),
2675 		sm_state_to_str(sfp->sm_state),
2676 		event_to_str(event));
2677 
2678 	sfp_sm_device(sfp, event);
2679 	sfp_sm_module(sfp, event);
2680 	sfp_sm_main(sfp, event);
2681 
2682 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
2683 		mod_state_to_str(sfp->sm_mod_state),
2684 		dev_state_to_str(sfp->sm_dev_state),
2685 		sm_state_to_str(sfp->sm_state));
2686 }
2687 
2688 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
2689 {
2690 	mutex_lock(&sfp->sm_mutex);
2691 	__sfp_sm_event(sfp, event);
2692 	mutex_unlock(&sfp->sm_mutex);
2693 }
2694 
2695 static void sfp_attach(struct sfp *sfp)
2696 {
2697 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
2698 }
2699 
2700 static void sfp_detach(struct sfp *sfp)
2701 {
2702 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
2703 }
2704 
2705 static void sfp_start(struct sfp *sfp)
2706 {
2707 	sfp_sm_event(sfp, SFP_E_DEV_UP);
2708 }
2709 
2710 static void sfp_stop(struct sfp *sfp)
2711 {
2712 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
2713 }
2714 
2715 static void sfp_set_signal_rate(struct sfp *sfp, unsigned int rate_kbd)
2716 {
2717 	unsigned int set;
2718 
2719 	sfp->rate_kbd = rate_kbd;
2720 
2721 	if (rate_kbd > sfp->rs_threshold_kbd)
2722 		set = sfp->rs_state_mask;
2723 	else
2724 		set = 0;
2725 
2726 	sfp_mod_state(sfp, SFP_F_RS0 | SFP_F_RS1, set);
2727 }
2728 
2729 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2730 {
2731 	/* locking... and check module is present */
2732 
2733 	if (sfp->id.ext.sff8472_compliance &&
2734 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2735 		modinfo->type = ETH_MODULE_SFF_8472;
2736 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2737 	} else {
2738 		modinfo->type = ETH_MODULE_SFF_8079;
2739 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2740 	}
2741 	return 0;
2742 }
2743 
2744 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2745 			     u8 *data)
2746 {
2747 	unsigned int first, last, len;
2748 	int ret;
2749 
2750 	if (!(sfp->state & SFP_F_PRESENT))
2751 		return -ENODEV;
2752 
2753 	if (ee->len == 0)
2754 		return -EINVAL;
2755 
2756 	first = ee->offset;
2757 	last = ee->offset + ee->len;
2758 	if (first < ETH_MODULE_SFF_8079_LEN) {
2759 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2760 		len -= first;
2761 
2762 		ret = sfp_read(sfp, false, first, data, len);
2763 		if (ret < 0)
2764 			return ret;
2765 
2766 		first += len;
2767 		data += len;
2768 	}
2769 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2770 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2771 		len -= first;
2772 		first -= ETH_MODULE_SFF_8079_LEN;
2773 
2774 		ret = sfp_read(sfp, true, first, data, len);
2775 		if (ret < 0)
2776 			return ret;
2777 	}
2778 	return 0;
2779 }
2780 
2781 static int sfp_module_eeprom_by_page(struct sfp *sfp,
2782 				     const struct ethtool_module_eeprom *page,
2783 				     struct netlink_ext_ack *extack)
2784 {
2785 	if (!(sfp->state & SFP_F_PRESENT))
2786 		return -ENODEV;
2787 
2788 	if (page->bank) {
2789 		NL_SET_ERR_MSG(extack, "Banks not supported");
2790 		return -EOPNOTSUPP;
2791 	}
2792 
2793 	if (page->page) {
2794 		NL_SET_ERR_MSG(extack, "Only page 0 supported");
2795 		return -EOPNOTSUPP;
2796 	}
2797 
2798 	if (page->i2c_address != 0x50 &&
2799 	    page->i2c_address != 0x51) {
2800 		NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
2801 		return -EOPNOTSUPP;
2802 	}
2803 
2804 	return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
2805 			page->data, page->length);
2806 };
2807 
2808 static const struct sfp_socket_ops sfp_module_ops = {
2809 	.attach = sfp_attach,
2810 	.detach = sfp_detach,
2811 	.start = sfp_start,
2812 	.stop = sfp_stop,
2813 	.set_signal_rate = sfp_set_signal_rate,
2814 	.module_info = sfp_module_info,
2815 	.module_eeprom = sfp_module_eeprom,
2816 	.module_eeprom_by_page = sfp_module_eeprom_by_page,
2817 };
2818 
2819 static void sfp_timeout(struct work_struct *work)
2820 {
2821 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2822 
2823 	rtnl_lock();
2824 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2825 	rtnl_unlock();
2826 }
2827 
2828 static void sfp_check_state(struct sfp *sfp)
2829 {
2830 	unsigned int state, i, changed;
2831 
2832 	rtnl_lock();
2833 	mutex_lock(&sfp->st_mutex);
2834 	state = sfp_get_state(sfp);
2835 	changed = state ^ sfp->state;
2836 	if (sfp->tx_fault_ignore)
2837 		changed &= SFP_F_PRESENT | SFP_F_LOS;
2838 	else
2839 		changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2840 
2841 	for (i = 0; i < GPIO_MAX; i++)
2842 		if (changed & BIT(i))
2843 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_names[i],
2844 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2845 
2846 	state |= sfp->state & SFP_F_OUTPUTS;
2847 	sfp->state = state;
2848 	mutex_unlock(&sfp->st_mutex);
2849 
2850 	mutex_lock(&sfp->sm_mutex);
2851 	if (changed & SFP_F_PRESENT)
2852 		__sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2853 				    SFP_E_INSERT : SFP_E_REMOVE);
2854 
2855 	if (changed & SFP_F_TX_FAULT)
2856 		__sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2857 				    SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2858 
2859 	if (changed & SFP_F_LOS)
2860 		__sfp_sm_event(sfp, state & SFP_F_LOS ?
2861 				    SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2862 	mutex_unlock(&sfp->sm_mutex);
2863 	rtnl_unlock();
2864 }
2865 
2866 static irqreturn_t sfp_irq(int irq, void *data)
2867 {
2868 	struct sfp *sfp = data;
2869 
2870 	sfp_check_state(sfp);
2871 
2872 	return IRQ_HANDLED;
2873 }
2874 
2875 static void sfp_poll(struct work_struct *work)
2876 {
2877 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2878 
2879 	sfp_check_state(sfp);
2880 
2881 	// st_mutex doesn't need to be held here for state_soft_mask,
2882 	// it's unimportant if we race while reading this.
2883 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2884 	    sfp->need_poll)
2885 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2886 }
2887 
2888 static struct sfp *sfp_alloc(struct device *dev)
2889 {
2890 	struct sfp *sfp;
2891 
2892 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2893 	if (!sfp)
2894 		return ERR_PTR(-ENOMEM);
2895 
2896 	sfp->dev = dev;
2897 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2898 
2899 	mutex_init(&sfp->sm_mutex);
2900 	mutex_init(&sfp->st_mutex);
2901 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2902 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2903 
2904 	sfp_hwmon_init(sfp);
2905 
2906 	return sfp;
2907 }
2908 
2909 static void sfp_cleanup(void *data)
2910 {
2911 	struct sfp *sfp = data;
2912 
2913 	sfp_hwmon_exit(sfp);
2914 
2915 	cancel_delayed_work_sync(&sfp->poll);
2916 	cancel_delayed_work_sync(&sfp->timeout);
2917 	if (sfp->i2c_mii) {
2918 		mdiobus_unregister(sfp->i2c_mii);
2919 		mdiobus_free(sfp->i2c_mii);
2920 	}
2921 	if (sfp->i2c)
2922 		i2c_put_adapter(sfp->i2c);
2923 	kfree(sfp);
2924 }
2925 
2926 static int sfp_i2c_get(struct sfp *sfp)
2927 {
2928 	struct fwnode_handle *h;
2929 	struct i2c_adapter *i2c;
2930 	int err;
2931 
2932 	h = fwnode_find_reference(dev_fwnode(sfp->dev), "i2c-bus", 0);
2933 	if (IS_ERR(h)) {
2934 		dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2935 		return -ENODEV;
2936 	}
2937 
2938 	i2c = i2c_get_adapter_by_fwnode(h);
2939 	if (!i2c) {
2940 		err = -EPROBE_DEFER;
2941 		goto put;
2942 	}
2943 
2944 	err = sfp_i2c_configure(sfp, i2c);
2945 	if (err)
2946 		i2c_put_adapter(i2c);
2947 put:
2948 	fwnode_handle_put(h);
2949 	return err;
2950 }
2951 
2952 static int sfp_probe(struct platform_device *pdev)
2953 {
2954 	const struct sff_data *sff;
2955 	char *sfp_irq_name;
2956 	struct sfp *sfp;
2957 	int err, i;
2958 
2959 	sfp = sfp_alloc(&pdev->dev);
2960 	if (IS_ERR(sfp))
2961 		return PTR_ERR(sfp);
2962 
2963 	platform_set_drvdata(pdev, sfp);
2964 
2965 	err = devm_add_action_or_reset(sfp->dev, sfp_cleanup, sfp);
2966 	if (err < 0)
2967 		return err;
2968 
2969 	sff = device_get_match_data(sfp->dev);
2970 	if (!sff)
2971 		sff = &sfp_data;
2972 
2973 	sfp->type = sff;
2974 
2975 	err = sfp_i2c_get(sfp);
2976 	if (err)
2977 		return err;
2978 
2979 	for (i = 0; i < GPIO_MAX; i++)
2980 		if (sff->gpios & BIT(i)) {
2981 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
2982 					   gpio_names[i], gpio_flags[i]);
2983 			if (IS_ERR(sfp->gpio[i]))
2984 				return PTR_ERR(sfp->gpio[i]);
2985 		}
2986 
2987 	sfp->state_hw_mask = SFP_F_PRESENT;
2988 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
2989 
2990 	sfp->get_state = sfp_gpio_get_state;
2991 	sfp->set_state = sfp_gpio_set_state;
2992 
2993 	/* Modules that have no detect signal are always present */
2994 	if (!(sfp->gpio[GPIO_MODDEF0]))
2995 		sfp->get_state = sff_gpio_get_state;
2996 
2997 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
2998 				 &sfp->max_power_mW);
2999 	if (sfp->max_power_mW < 1000) {
3000 		if (sfp->max_power_mW)
3001 			dev_warn(sfp->dev,
3002 				 "Firmware bug: host maximum power should be at least 1W\n");
3003 		sfp->max_power_mW = 1000;
3004 	}
3005 
3006 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
3007 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
3008 
3009 	/* Get the initial state, and always signal TX disable,
3010 	 * since the network interface will not be up.
3011 	 */
3012 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
3013 
3014 	if (sfp->gpio[GPIO_RS0] &&
3015 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RS0]))
3016 		sfp->state |= SFP_F_RS0;
3017 	sfp_set_state(sfp, sfp->state);
3018 	sfp_module_tx_disable(sfp);
3019 	if (sfp->state & SFP_F_PRESENT) {
3020 		rtnl_lock();
3021 		sfp_sm_event(sfp, SFP_E_INSERT);
3022 		rtnl_unlock();
3023 	}
3024 
3025 	for (i = 0; i < GPIO_MAX; i++) {
3026 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
3027 			continue;
3028 
3029 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
3030 		if (sfp->gpio_irq[i] < 0) {
3031 			sfp->gpio_irq[i] = 0;
3032 			sfp->need_poll = true;
3033 			continue;
3034 		}
3035 
3036 		sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
3037 					      "%s-%s", dev_name(sfp->dev),
3038 					      gpio_names[i]);
3039 
3040 		if (!sfp_irq_name)
3041 			return -ENOMEM;
3042 
3043 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
3044 						NULL, sfp_irq,
3045 						IRQF_ONESHOT |
3046 						IRQF_TRIGGER_RISING |
3047 						IRQF_TRIGGER_FALLING,
3048 						sfp_irq_name, sfp);
3049 		if (err) {
3050 			sfp->gpio_irq[i] = 0;
3051 			sfp->need_poll = true;
3052 		}
3053 	}
3054 
3055 	if (sfp->need_poll)
3056 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
3057 
3058 	/* We could have an issue in cases no Tx disable pin is available or
3059 	 * wired as modules using a laser as their light source will continue to
3060 	 * be active when the fiber is removed. This could be a safety issue and
3061 	 * we should at least warn the user about that.
3062 	 */
3063 	if (!sfp->gpio[GPIO_TX_DISABLE])
3064 		dev_warn(sfp->dev,
3065 			 "No tx_disable pin: SFP modules will always be emitting.\n");
3066 
3067 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
3068 	if (!sfp->sfp_bus)
3069 		return -ENOMEM;
3070 
3071 	sfp_debugfs_init(sfp);
3072 
3073 	return 0;
3074 }
3075 
3076 static int sfp_remove(struct platform_device *pdev)
3077 {
3078 	struct sfp *sfp = platform_get_drvdata(pdev);
3079 
3080 	sfp_debugfs_exit(sfp);
3081 	sfp_unregister_socket(sfp->sfp_bus);
3082 
3083 	rtnl_lock();
3084 	sfp_sm_event(sfp, SFP_E_REMOVE);
3085 	rtnl_unlock();
3086 
3087 	return 0;
3088 }
3089 
3090 static void sfp_shutdown(struct platform_device *pdev)
3091 {
3092 	struct sfp *sfp = platform_get_drvdata(pdev);
3093 	int i;
3094 
3095 	for (i = 0; i < GPIO_MAX; i++) {
3096 		if (!sfp->gpio_irq[i])
3097 			continue;
3098 
3099 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
3100 	}
3101 
3102 	cancel_delayed_work_sync(&sfp->poll);
3103 	cancel_delayed_work_sync(&sfp->timeout);
3104 }
3105 
3106 static struct platform_driver sfp_driver = {
3107 	.probe = sfp_probe,
3108 	.remove = sfp_remove,
3109 	.shutdown = sfp_shutdown,
3110 	.driver = {
3111 		.name = "sfp",
3112 		.of_match_table = sfp_of_match,
3113 	},
3114 };
3115 
3116 static int sfp_init(void)
3117 {
3118 	poll_jiffies = msecs_to_jiffies(100);
3119 
3120 	return platform_driver_register(&sfp_driver);
3121 }
3122 module_init(sfp_init);
3123 
3124 static void sfp_exit(void)
3125 {
3126 	platform_driver_unregister(&sfp_driver);
3127 }
3128 module_exit(sfp_exit);
3129 
3130 MODULE_ALIAS("platform:sfp");
3131 MODULE_AUTHOR("Russell King");
3132 MODULE_LICENSE("GPL v2");
3133