xref: /linux/drivers/net/phy/sfp.c (revision 2bd87951de659df3381ce083342aaf5b1ea24689)
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		25
195 
196 /* SFP module presence detection is poor: the three MOD DEF signals are
197  * the same length on the PCB, which means it's possible for MOD DEF 0 to
198  * connect before the I2C bus on MOD DEF 1/2.
199  *
200  * The SFF-8472 specifies t_serial ("Time from power on until module is
201  * ready for data transmission over the two wire serial bus.") as 300ms.
202  */
203 #define T_SERIAL		msecs_to_jiffies(300)
204 #define T_HPOWER_LEVEL		msecs_to_jiffies(300)
205 #define T_PROBE_RETRY_INIT	msecs_to_jiffies(100)
206 #define R_PROBE_RETRY_INIT	10
207 #define T_PROBE_RETRY_SLOW	msecs_to_jiffies(5000)
208 #define R_PROBE_RETRY_SLOW	12
209 
210 /* 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_ignore_mask;
261 	unsigned int state;
262 
263 	struct delayed_work poll;
264 	struct delayed_work timeout;
265 	struct mutex sm_mutex;			/* Protects state machine */
266 	unsigned char sm_mod_state;
267 	unsigned char sm_mod_tries_init;
268 	unsigned char sm_mod_tries;
269 	unsigned char sm_dev_state;
270 	unsigned short sm_state;
271 	unsigned char sm_fault_retries;
272 	unsigned char sm_phy_retries;
273 
274 	struct sfp_eeprom_id id;
275 	unsigned int module_power_mW;
276 	unsigned int module_t_start_up;
277 	unsigned int module_t_wait;
278 	unsigned int phy_t_retry;
279 
280 	unsigned int rate_kbd;
281 	unsigned int rs_threshold_kbd;
282 	unsigned int rs_state_mask;
283 
284 	bool have_a2;
285 
286 	const struct sfp_quirk *quirk;
287 
288 #if IS_ENABLED(CONFIG_HWMON)
289 	struct sfp_diag diag;
290 	struct delayed_work hwmon_probe;
291 	unsigned int hwmon_tries;
292 	struct device *hwmon_dev;
293 	char *hwmon_name;
294 #endif
295 
296 #if IS_ENABLED(CONFIG_DEBUG_FS)
297 	struct dentry *debugfs_dir;
298 #endif
299 };
300 
301 static bool sff_module_supported(const struct sfp_eeprom_id *id)
302 {
303 	return id->base.phys_id == SFF8024_ID_SFF_8472 &&
304 	       id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
305 }
306 
307 static const struct sff_data sff_data = {
308 	.gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
309 	.module_supported = sff_module_supported,
310 };
311 
312 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
313 {
314 	if (id->base.phys_id == SFF8024_ID_SFP &&
315 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP)
316 		return true;
317 
318 	/* SFP GPON module Ubiquiti U-Fiber Instant has in its EEPROM stored
319 	 * phys id SFF instead of SFP. Therefore mark this module explicitly
320 	 * as supported based on vendor name and pn match.
321 	 */
322 	if (id->base.phys_id == SFF8024_ID_SFF_8472 &&
323 	    id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP &&
324 	    !memcmp(id->base.vendor_name, "UBNT            ", 16) &&
325 	    !memcmp(id->base.vendor_pn, "UF-INSTANT      ", 16))
326 		return true;
327 
328 	return false;
329 }
330 
331 static const struct sff_data sfp_data = {
332 	.gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
333 		 SFP_F_TX_DISABLE | SFP_F_RS0 | SFP_F_RS1,
334 	.module_supported = sfp_module_supported,
335 };
336 
337 static const struct of_device_id sfp_of_match[] = {
338 	{ .compatible = "sff,sff", .data = &sff_data, },
339 	{ .compatible = "sff,sfp", .data = &sfp_data, },
340 	{ },
341 };
342 MODULE_DEVICE_TABLE(of, sfp_of_match);
343 
344 static void sfp_fixup_long_startup(struct sfp *sfp)
345 {
346 	sfp->module_t_start_up = T_START_UP_BAD_GPON;
347 }
348 
349 static void sfp_fixup_ignore_los(struct sfp *sfp)
350 {
351 	/* This forces LOS to zero, so we ignore transitions */
352 	sfp->state_ignore_mask |= SFP_F_LOS;
353 	/* Make sure that LOS options are clear */
354 	sfp->id.ext.options &= ~cpu_to_be16(SFP_OPTIONS_LOS_INVERTED |
355 					    SFP_OPTIONS_LOS_NORMAL);
356 }
357 
358 static void sfp_fixup_ignore_tx_fault(struct sfp *sfp)
359 {
360 	sfp->state_ignore_mask |= SFP_F_TX_FAULT;
361 }
362 
363 static void sfp_fixup_nokia(struct sfp *sfp)
364 {
365 	sfp_fixup_long_startup(sfp);
366 	sfp_fixup_ignore_los(sfp);
367 }
368 
369 // For 10GBASE-T short-reach modules
370 static void sfp_fixup_10gbaset_30m(struct sfp *sfp)
371 {
372 	sfp->id.base.connector = SFF8024_CONNECTOR_RJ45;
373 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SR;
374 }
375 
376 static void sfp_fixup_rollball(struct sfp *sfp)
377 {
378 	sfp->mdio_protocol = MDIO_I2C_ROLLBALL;
379 
380 	/* RollBall modules may disallow access to PHY registers for up to 25
381 	 * seconds, and the reads return 0xffff before that. Increase the time
382 	 * between PHY probe retries from 50ms to 1s so that we will wait for
383 	 * the PHY for a sufficient amount of time.
384 	 */
385 	sfp->phy_t_retry = msecs_to_jiffies(1000);
386 }
387 
388 static void sfp_fixup_fs_10gt(struct sfp *sfp)
389 {
390 	sfp_fixup_10gbaset_30m(sfp);
391 	sfp_fixup_rollball(sfp);
392 
393 	/* The RollBall fixup is not enough for FS modules, the AQR chip inside
394 	 * them does not return 0xffff for PHY ID registers in all MMDs for the
395 	 * while initializing. They need a 4 second wait before accessing PHY.
396 	 */
397 	sfp->module_t_wait = msecs_to_jiffies(4000);
398 }
399 
400 static void sfp_fixup_halny_gsfp(struct sfp *sfp)
401 {
402 	/* Ignore the TX_FAULT and LOS signals on this module.
403 	 * these are possibly used for other purposes on this
404 	 * module, e.g. a serial port.
405 	 */
406 	sfp->state_hw_mask &= ~(SFP_F_TX_FAULT | SFP_F_LOS);
407 }
408 
409 static void sfp_fixup_rollball_cc(struct sfp *sfp)
410 {
411 	sfp_fixup_rollball(sfp);
412 
413 	/* Some RollBall SFPs may have wrong (zero) extended compliance code
414 	 * burned in EEPROM. For PHY probing we need the correct one.
415 	 */
416 	sfp->id.base.extended_cc = SFF8024_ECC_10GBASE_T_SFI;
417 }
418 
419 static void sfp_quirk_2500basex(const struct sfp_eeprom_id *id,
420 				unsigned long *modes,
421 				unsigned long *interfaces)
422 {
423 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseX_Full_BIT, modes);
424 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
425 }
426 
427 static void sfp_quirk_disable_autoneg(const struct sfp_eeprom_id *id,
428 				      unsigned long *modes,
429 				      unsigned long *interfaces)
430 {
431 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, modes);
432 }
433 
434 static void sfp_quirk_oem_2_5g(const struct sfp_eeprom_id *id,
435 			       unsigned long *modes,
436 			       unsigned long *interfaces)
437 {
438 	/* Copper 2.5G SFP */
439 	linkmode_set_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT, modes);
440 	__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
441 	sfp_quirk_disable_autoneg(id, modes, interfaces);
442 }
443 
444 static void sfp_quirk_ubnt_uf_instant(const struct sfp_eeprom_id *id,
445 				      unsigned long *modes,
446 				      unsigned long *interfaces)
447 {
448 	/* Ubiquiti U-Fiber Instant module claims that support all transceiver
449 	 * types including 10G Ethernet which is not truth. So clear all claimed
450 	 * modes and set only one mode which module supports: 1000baseX_Full.
451 	 */
452 	linkmode_zero(modes);
453 	linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT, modes);
454 }
455 
456 #define SFP_QUIRK(_v, _p, _m, _f) \
457 	{ .vendor = _v, .part = _p, .modes = _m, .fixup = _f, }
458 #define SFP_QUIRK_M(_v, _p, _m) SFP_QUIRK(_v, _p, _m, NULL)
459 #define SFP_QUIRK_F(_v, _p, _f) SFP_QUIRK(_v, _p, NULL, _f)
460 
461 static const struct sfp_quirk sfp_quirks[] = {
462 	// Alcatel Lucent G-010S-P can operate at 2500base-X, but incorrectly
463 	// report 2500MBd NRZ in their EEPROM
464 	SFP_QUIRK_M("ALCATELLUCENT", "G010SP", sfp_quirk_2500basex),
465 
466 	// Alcatel Lucent G-010S-A can operate at 2500base-X, but report 3.2GBd
467 	// NRZ in their EEPROM
468 	SFP_QUIRK("ALCATELLUCENT", "3FE46541AA", sfp_quirk_2500basex,
469 		  sfp_fixup_nokia),
470 
471 	// Fiberstore SFP-10G-T doesn't identify as copper, and uses the
472 	// Rollball protocol to talk to the PHY.
473 	SFP_QUIRK_F("FS", "SFP-10G-T", sfp_fixup_fs_10gt),
474 
475 	// Fiberstore GPON-ONU-34-20BI can operate at 2500base-X, but report 1.2GBd
476 	// NRZ in their EEPROM
477 	SFP_QUIRK("FS", "GPON-ONU-34-20BI", sfp_quirk_2500basex,
478 		  sfp_fixup_ignore_tx_fault),
479 
480 	SFP_QUIRK_F("HALNy", "HL-GSFP", sfp_fixup_halny_gsfp),
481 
482 	// HG MXPD-483II-F 2.5G supports 2500Base-X, but incorrectly reports
483 	// 2600MBd in their EERPOM
484 	SFP_QUIRK_M("HG GENUINE", "MXPD-483II", sfp_quirk_2500basex),
485 
486 	// Huawei MA5671A can operate at 2500base-X, but report 1.2GBd NRZ in
487 	// their EEPROM
488 	SFP_QUIRK("HUAWEI", "MA5671A", sfp_quirk_2500basex,
489 		  sfp_fixup_ignore_tx_fault),
490 
491 	// FS 2.5G Base-T
492 	SFP_QUIRK_M("FS", "SFP-2.5G-T", sfp_quirk_oem_2_5g),
493 
494 	// Lantech 8330-262D-E can operate at 2500base-X, but incorrectly report
495 	// 2500MBd NRZ in their EEPROM
496 	SFP_QUIRK_M("Lantech", "8330-262D-E", sfp_quirk_2500basex),
497 
498 	SFP_QUIRK_M("UBNT", "UF-INSTANT", sfp_quirk_ubnt_uf_instant),
499 
500 	// Walsun HXSX-ATR[CI]-1 don't identify as copper, and use the
501 	// Rollball protocol to talk to the PHY.
502 	SFP_QUIRK_F("Walsun", "HXSX-ATRC-1", sfp_fixup_fs_10gt),
503 	SFP_QUIRK_F("Walsun", "HXSX-ATRI-1", sfp_fixup_fs_10gt),
504 
505 	SFP_QUIRK_F("OEM", "SFP-10G-T", sfp_fixup_rollball_cc),
506 	SFP_QUIRK_M("OEM", "SFP-2.5G-T", sfp_quirk_oem_2_5g),
507 	SFP_QUIRK_F("OEM", "RTSFP-10", sfp_fixup_rollball_cc),
508 	SFP_QUIRK_F("OEM", "RTSFP-10G", sfp_fixup_rollball_cc),
509 	SFP_QUIRK_F("Turris", "RTSFP-2.5G", sfp_fixup_rollball),
510 	SFP_QUIRK_F("Turris", "RTSFP-10", sfp_fixup_rollball),
511 	SFP_QUIRK_F("Turris", "RTSFP-10G", sfp_fixup_rollball),
512 };
513 
514 static size_t sfp_strlen(const char *str, size_t maxlen)
515 {
516 	size_t size, i;
517 
518 	/* Trailing characters should be filled with space chars, but
519 	 * some manufacturers can't read SFF-8472 and use NUL.
520 	 */
521 	for (i = 0, size = 0; i < maxlen; i++)
522 		if (str[i] != ' ' && str[i] != '\0')
523 			size = i + 1;
524 
525 	return size;
526 }
527 
528 static bool sfp_match(const char *qs, const char *str, size_t len)
529 {
530 	if (!qs)
531 		return true;
532 	if (strlen(qs) != len)
533 		return false;
534 	return !strncmp(qs, str, len);
535 }
536 
537 static const struct sfp_quirk *sfp_lookup_quirk(const struct sfp_eeprom_id *id)
538 {
539 	const struct sfp_quirk *q;
540 	unsigned int i;
541 	size_t vs, ps;
542 
543 	vs = sfp_strlen(id->base.vendor_name, ARRAY_SIZE(id->base.vendor_name));
544 	ps = sfp_strlen(id->base.vendor_pn, ARRAY_SIZE(id->base.vendor_pn));
545 
546 	for (i = 0, q = sfp_quirks; i < ARRAY_SIZE(sfp_quirks); i++, q++)
547 		if (sfp_match(q->vendor, id->base.vendor_name, vs) &&
548 		    sfp_match(q->part, id->base.vendor_pn, ps))
549 			return q;
550 
551 	return NULL;
552 }
553 
554 static unsigned long poll_jiffies;
555 
556 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
557 {
558 	unsigned int i, state, v;
559 
560 	for (i = state = 0; i < GPIO_MAX; i++) {
561 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
562 			continue;
563 
564 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
565 		if (v)
566 			state |= BIT(i);
567 	}
568 
569 	return state;
570 }
571 
572 static unsigned int sff_gpio_get_state(struct sfp *sfp)
573 {
574 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
575 }
576 
577 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
578 {
579 	unsigned int drive;
580 
581 	if (state & SFP_F_PRESENT)
582 		/* If the module is present, drive the requested signals */
583 		drive = sfp->state_hw_drive;
584 	else
585 		/* Otherwise, let them float to the pull-ups */
586 		drive = 0;
587 
588 	if (sfp->gpio[GPIO_TX_DISABLE]) {
589 		if (drive & SFP_F_TX_DISABLE)
590 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
591 					       state & SFP_F_TX_DISABLE);
592 		else
593 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
594 	}
595 
596 	if (sfp->gpio[GPIO_RS0]) {
597 		if (drive & SFP_F_RS0)
598 			gpiod_direction_output(sfp->gpio[GPIO_RS0],
599 					       state & SFP_F_RS0);
600 		else
601 			gpiod_direction_input(sfp->gpio[GPIO_RS0]);
602 	}
603 
604 	if (sfp->gpio[GPIO_RS1]) {
605 		if (drive & SFP_F_RS1)
606 			gpiod_direction_output(sfp->gpio[GPIO_RS1],
607 					       state & SFP_F_RS1);
608 		else
609 			gpiod_direction_input(sfp->gpio[GPIO_RS1]);
610 	}
611 }
612 
613 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
614 			size_t len)
615 {
616 	struct i2c_msg msgs[2];
617 	u8 bus_addr = a2 ? 0x51 : 0x50;
618 	size_t block_size = sfp->i2c_block_size;
619 	size_t this_len;
620 	int ret;
621 
622 	msgs[0].addr = bus_addr;
623 	msgs[0].flags = 0;
624 	msgs[0].len = 1;
625 	msgs[0].buf = &dev_addr;
626 	msgs[1].addr = bus_addr;
627 	msgs[1].flags = I2C_M_RD;
628 	msgs[1].len = len;
629 	msgs[1].buf = buf;
630 
631 	while (len) {
632 		this_len = len;
633 		if (this_len > block_size)
634 			this_len = block_size;
635 
636 		msgs[1].len = this_len;
637 
638 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
639 		if (ret < 0)
640 			return ret;
641 
642 		if (ret != ARRAY_SIZE(msgs))
643 			break;
644 
645 		msgs[1].buf += this_len;
646 		dev_addr += this_len;
647 		len -= this_len;
648 	}
649 
650 	return msgs[1].buf - (u8 *)buf;
651 }
652 
653 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
654 	size_t len)
655 {
656 	struct i2c_msg msgs[1];
657 	u8 bus_addr = a2 ? 0x51 : 0x50;
658 	int ret;
659 
660 	msgs[0].addr = bus_addr;
661 	msgs[0].flags = 0;
662 	msgs[0].len = 1 + len;
663 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
664 	if (!msgs[0].buf)
665 		return -ENOMEM;
666 
667 	msgs[0].buf[0] = dev_addr;
668 	memcpy(&msgs[0].buf[1], buf, len);
669 
670 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
671 
672 	kfree(msgs[0].buf);
673 
674 	if (ret < 0)
675 		return ret;
676 
677 	return ret == ARRAY_SIZE(msgs) ? len : 0;
678 }
679 
680 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
681 {
682 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
683 		return -EINVAL;
684 
685 	sfp->i2c = i2c;
686 	sfp->read = sfp_i2c_read;
687 	sfp->write = sfp_i2c_write;
688 
689 	return 0;
690 }
691 
692 static int sfp_i2c_mdiobus_create(struct sfp *sfp)
693 {
694 	struct mii_bus *i2c_mii;
695 	int ret;
696 
697 	i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, sfp->mdio_protocol);
698 	if (IS_ERR(i2c_mii))
699 		return PTR_ERR(i2c_mii);
700 
701 	i2c_mii->name = "SFP I2C Bus";
702 	i2c_mii->phy_mask = ~0;
703 
704 	ret = mdiobus_register(i2c_mii);
705 	if (ret < 0) {
706 		mdiobus_free(i2c_mii);
707 		return ret;
708 	}
709 
710 	sfp->i2c_mii = i2c_mii;
711 
712 	return 0;
713 }
714 
715 static void sfp_i2c_mdiobus_destroy(struct sfp *sfp)
716 {
717 	mdiobus_unregister(sfp->i2c_mii);
718 	sfp->i2c_mii = NULL;
719 }
720 
721 /* Interface */
722 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
723 {
724 	return sfp->read(sfp, a2, addr, buf, len);
725 }
726 
727 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
728 {
729 	return sfp->write(sfp, a2, addr, buf, len);
730 }
731 
732 static int sfp_modify_u8(struct sfp *sfp, bool a2, u8 addr, u8 mask, u8 val)
733 {
734 	int ret;
735 	u8 old, v;
736 
737 	ret = sfp_read(sfp, a2, addr, &old, sizeof(old));
738 	if (ret != sizeof(old))
739 		return ret;
740 
741 	v = (old & ~mask) | (val & mask);
742 	if (v == old)
743 		return sizeof(v);
744 
745 	return sfp_write(sfp, a2, addr, &v, sizeof(v));
746 }
747 
748 static unsigned int sfp_soft_get_state(struct sfp *sfp)
749 {
750 	unsigned int state = 0;
751 	u8 status;
752 	int ret;
753 
754 	ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
755 	if (ret == sizeof(status)) {
756 		if (status & SFP_STATUS_RX_LOS)
757 			state |= SFP_F_LOS;
758 		if (status & SFP_STATUS_TX_FAULT)
759 			state |= SFP_F_TX_FAULT;
760 	} else {
761 		dev_err_ratelimited(sfp->dev,
762 				    "failed to read SFP soft status: %pe\n",
763 				    ERR_PTR(ret));
764 		/* Preserve the current state */
765 		state = sfp->state;
766 	}
767 
768 	return state & sfp->state_soft_mask;
769 }
770 
771 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state,
772 			       unsigned int soft)
773 {
774 	u8 mask = 0;
775 	u8 val = 0;
776 
777 	if (soft & SFP_F_TX_DISABLE)
778 		mask |= SFP_STATUS_TX_DISABLE_FORCE;
779 	if (state & SFP_F_TX_DISABLE)
780 		val |= SFP_STATUS_TX_DISABLE_FORCE;
781 
782 	if (soft & SFP_F_RS0)
783 		mask |= SFP_STATUS_RS0_SELECT;
784 	if (state & SFP_F_RS0)
785 		val |= SFP_STATUS_RS0_SELECT;
786 
787 	if (mask)
788 		sfp_modify_u8(sfp, true, SFP_STATUS, mask, val);
789 
790 	val = mask = 0;
791 	if (soft & SFP_F_RS1)
792 		mask |= SFP_EXT_STATUS_RS1_SELECT;
793 	if (state & SFP_F_RS1)
794 		val |= SFP_EXT_STATUS_RS1_SELECT;
795 
796 	if (mask)
797 		sfp_modify_u8(sfp, true, SFP_EXT_STATUS, mask, val);
798 }
799 
800 static void sfp_soft_start_poll(struct sfp *sfp)
801 {
802 	const struct sfp_eeprom_id *id = &sfp->id;
803 	unsigned int mask = 0;
804 
805 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE)
806 		mask |= SFP_F_TX_DISABLE;
807 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT)
808 		mask |= SFP_F_TX_FAULT;
809 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS)
810 		mask |= SFP_F_LOS;
811 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RATE_SELECT)
812 		mask |= sfp->rs_state_mask;
813 
814 	mutex_lock(&sfp->st_mutex);
815 	// Poll the soft state for hardware pins we want to ignore
816 	sfp->state_soft_mask = ~sfp->state_hw_mask & ~sfp->state_ignore_mask &
817 			       mask;
818 
819 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
820 	    !sfp->need_poll)
821 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
822 	mutex_unlock(&sfp->st_mutex);
823 }
824 
825 static void sfp_soft_stop_poll(struct sfp *sfp)
826 {
827 	mutex_lock(&sfp->st_mutex);
828 	sfp->state_soft_mask = 0;
829 	mutex_unlock(&sfp->st_mutex);
830 }
831 
832 /* sfp_get_state() - must be called with st_mutex held, or in the
833  * initialisation path.
834  */
835 static unsigned int sfp_get_state(struct sfp *sfp)
836 {
837 	unsigned int soft = sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT);
838 	unsigned int state;
839 
840 	state = sfp->get_state(sfp) & sfp->state_hw_mask;
841 	if (state & SFP_F_PRESENT && soft)
842 		state |= sfp_soft_get_state(sfp);
843 
844 	return state;
845 }
846 
847 /* sfp_set_state() - must be called with st_mutex held, or in the
848  * initialisation path.
849  */
850 static void sfp_set_state(struct sfp *sfp, unsigned int state)
851 {
852 	unsigned int soft;
853 
854 	sfp->set_state(sfp, state);
855 
856 	soft = sfp->state_soft_mask & SFP_F_OUTPUTS;
857 	if (state & SFP_F_PRESENT && soft)
858 		sfp_soft_set_state(sfp, state, soft);
859 }
860 
861 static void sfp_mod_state(struct sfp *sfp, unsigned int mask, unsigned int set)
862 {
863 	mutex_lock(&sfp->st_mutex);
864 	sfp->state = (sfp->state & ~mask) | set;
865 	sfp_set_state(sfp, sfp->state);
866 	mutex_unlock(&sfp->st_mutex);
867 }
868 
869 static unsigned int sfp_check(void *buf, size_t len)
870 {
871 	u8 *p, check;
872 
873 	for (p = buf, check = 0; len; p++, len--)
874 		check += *p;
875 
876 	return check;
877 }
878 
879 /* hwmon */
880 #if IS_ENABLED(CONFIG_HWMON)
881 static umode_t sfp_hwmon_is_visible(const void *data,
882 				    enum hwmon_sensor_types type,
883 				    u32 attr, int channel)
884 {
885 	const struct sfp *sfp = data;
886 
887 	switch (type) {
888 	case hwmon_temp:
889 		switch (attr) {
890 		case hwmon_temp_min_alarm:
891 		case hwmon_temp_max_alarm:
892 		case hwmon_temp_lcrit_alarm:
893 		case hwmon_temp_crit_alarm:
894 		case hwmon_temp_min:
895 		case hwmon_temp_max:
896 		case hwmon_temp_lcrit:
897 		case hwmon_temp_crit:
898 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
899 				return 0;
900 			fallthrough;
901 		case hwmon_temp_input:
902 		case hwmon_temp_label:
903 			return 0444;
904 		default:
905 			return 0;
906 		}
907 	case hwmon_in:
908 		switch (attr) {
909 		case hwmon_in_min_alarm:
910 		case hwmon_in_max_alarm:
911 		case hwmon_in_lcrit_alarm:
912 		case hwmon_in_crit_alarm:
913 		case hwmon_in_min:
914 		case hwmon_in_max:
915 		case hwmon_in_lcrit:
916 		case hwmon_in_crit:
917 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
918 				return 0;
919 			fallthrough;
920 		case hwmon_in_input:
921 		case hwmon_in_label:
922 			return 0444;
923 		default:
924 			return 0;
925 		}
926 	case hwmon_curr:
927 		switch (attr) {
928 		case hwmon_curr_min_alarm:
929 		case hwmon_curr_max_alarm:
930 		case hwmon_curr_lcrit_alarm:
931 		case hwmon_curr_crit_alarm:
932 		case hwmon_curr_min:
933 		case hwmon_curr_max:
934 		case hwmon_curr_lcrit:
935 		case hwmon_curr_crit:
936 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
937 				return 0;
938 			fallthrough;
939 		case hwmon_curr_input:
940 		case hwmon_curr_label:
941 			return 0444;
942 		default:
943 			return 0;
944 		}
945 	case hwmon_power:
946 		/* External calibration of receive power requires
947 		 * floating point arithmetic. Doing that in the kernel
948 		 * is not easy, so just skip it. If the module does
949 		 * not require external calibration, we can however
950 		 * show receiver power, since FP is then not needed.
951 		 */
952 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
953 		    channel == 1)
954 			return 0;
955 		switch (attr) {
956 		case hwmon_power_min_alarm:
957 		case hwmon_power_max_alarm:
958 		case hwmon_power_lcrit_alarm:
959 		case hwmon_power_crit_alarm:
960 		case hwmon_power_min:
961 		case hwmon_power_max:
962 		case hwmon_power_lcrit:
963 		case hwmon_power_crit:
964 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
965 				return 0;
966 			fallthrough;
967 		case hwmon_power_input:
968 		case hwmon_power_label:
969 			return 0444;
970 		default:
971 			return 0;
972 		}
973 	default:
974 		return 0;
975 	}
976 }
977 
978 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
979 {
980 	__be16 val;
981 	int err;
982 
983 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
984 	if (err < 0)
985 		return err;
986 
987 	*value = be16_to_cpu(val);
988 
989 	return 0;
990 }
991 
992 static void sfp_hwmon_to_rx_power(long *value)
993 {
994 	*value = DIV_ROUND_CLOSEST(*value, 10);
995 }
996 
997 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
998 				long *value)
999 {
1000 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
1001 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
1002 }
1003 
1004 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
1005 {
1006 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
1007 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
1008 
1009 	if (*value >= 0x8000)
1010 		*value -= 0x10000;
1011 
1012 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
1013 }
1014 
1015 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
1016 {
1017 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
1018 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
1019 
1020 	*value = DIV_ROUND_CLOSEST(*value, 10);
1021 }
1022 
1023 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
1024 {
1025 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
1026 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
1027 
1028 	*value = DIV_ROUND_CLOSEST(*value, 500);
1029 }
1030 
1031 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
1032 {
1033 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
1034 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
1035 
1036 	*value = DIV_ROUND_CLOSEST(*value, 10);
1037 }
1038 
1039 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
1040 {
1041 	int err;
1042 
1043 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1044 	if (err < 0)
1045 		return err;
1046 
1047 	sfp_hwmon_calibrate_temp(sfp, value);
1048 
1049 	return 0;
1050 }
1051 
1052 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
1053 {
1054 	int err;
1055 
1056 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1057 	if (err < 0)
1058 		return err;
1059 
1060 	sfp_hwmon_calibrate_vcc(sfp, value);
1061 
1062 	return 0;
1063 }
1064 
1065 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
1066 {
1067 	int err;
1068 
1069 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1070 	if (err < 0)
1071 		return err;
1072 
1073 	sfp_hwmon_calibrate_bias(sfp, value);
1074 
1075 	return 0;
1076 }
1077 
1078 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
1079 {
1080 	int err;
1081 
1082 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1083 	if (err < 0)
1084 		return err;
1085 
1086 	sfp_hwmon_calibrate_tx_power(sfp, value);
1087 
1088 	return 0;
1089 }
1090 
1091 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
1092 {
1093 	int err;
1094 
1095 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1096 	if (err < 0)
1097 		return err;
1098 
1099 	sfp_hwmon_to_rx_power(value);
1100 
1101 	return 0;
1102 }
1103 
1104 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
1105 {
1106 	u8 status;
1107 	int err;
1108 
1109 	switch (attr) {
1110 	case hwmon_temp_input:
1111 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
1112 
1113 	case hwmon_temp_lcrit:
1114 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
1115 		sfp_hwmon_calibrate_temp(sfp, value);
1116 		return 0;
1117 
1118 	case hwmon_temp_min:
1119 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
1120 		sfp_hwmon_calibrate_temp(sfp, value);
1121 		return 0;
1122 	case hwmon_temp_max:
1123 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
1124 		sfp_hwmon_calibrate_temp(sfp, value);
1125 		return 0;
1126 
1127 	case hwmon_temp_crit:
1128 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
1129 		sfp_hwmon_calibrate_temp(sfp, value);
1130 		return 0;
1131 
1132 	case hwmon_temp_lcrit_alarm:
1133 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1134 		if (err < 0)
1135 			return err;
1136 
1137 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
1138 		return 0;
1139 
1140 	case hwmon_temp_min_alarm:
1141 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1142 		if (err < 0)
1143 			return err;
1144 
1145 		*value = !!(status & SFP_WARN0_TEMP_LOW);
1146 		return 0;
1147 
1148 	case hwmon_temp_max_alarm:
1149 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1150 		if (err < 0)
1151 			return err;
1152 
1153 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
1154 		return 0;
1155 
1156 	case hwmon_temp_crit_alarm:
1157 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1158 		if (err < 0)
1159 			return err;
1160 
1161 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
1162 		return 0;
1163 	default:
1164 		return -EOPNOTSUPP;
1165 	}
1166 
1167 	return -EOPNOTSUPP;
1168 }
1169 
1170 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
1171 {
1172 	u8 status;
1173 	int err;
1174 
1175 	switch (attr) {
1176 	case hwmon_in_input:
1177 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
1178 
1179 	case hwmon_in_lcrit:
1180 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
1181 		sfp_hwmon_calibrate_vcc(sfp, value);
1182 		return 0;
1183 
1184 	case hwmon_in_min:
1185 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
1186 		sfp_hwmon_calibrate_vcc(sfp, value);
1187 		return 0;
1188 
1189 	case hwmon_in_max:
1190 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
1191 		sfp_hwmon_calibrate_vcc(sfp, value);
1192 		return 0;
1193 
1194 	case hwmon_in_crit:
1195 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
1196 		sfp_hwmon_calibrate_vcc(sfp, value);
1197 		return 0;
1198 
1199 	case hwmon_in_lcrit_alarm:
1200 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1201 		if (err < 0)
1202 			return err;
1203 
1204 		*value = !!(status & SFP_ALARM0_VCC_LOW);
1205 		return 0;
1206 
1207 	case hwmon_in_min_alarm:
1208 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1209 		if (err < 0)
1210 			return err;
1211 
1212 		*value = !!(status & SFP_WARN0_VCC_LOW);
1213 		return 0;
1214 
1215 	case hwmon_in_max_alarm:
1216 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1217 		if (err < 0)
1218 			return err;
1219 
1220 		*value = !!(status & SFP_WARN0_VCC_HIGH);
1221 		return 0;
1222 
1223 	case hwmon_in_crit_alarm:
1224 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1225 		if (err < 0)
1226 			return err;
1227 
1228 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
1229 		return 0;
1230 	default:
1231 		return -EOPNOTSUPP;
1232 	}
1233 
1234 	return -EOPNOTSUPP;
1235 }
1236 
1237 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
1238 {
1239 	u8 status;
1240 	int err;
1241 
1242 	switch (attr) {
1243 	case hwmon_curr_input:
1244 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
1245 
1246 	case hwmon_curr_lcrit:
1247 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
1248 		sfp_hwmon_calibrate_bias(sfp, value);
1249 		return 0;
1250 
1251 	case hwmon_curr_min:
1252 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
1253 		sfp_hwmon_calibrate_bias(sfp, value);
1254 		return 0;
1255 
1256 	case hwmon_curr_max:
1257 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
1258 		sfp_hwmon_calibrate_bias(sfp, value);
1259 		return 0;
1260 
1261 	case hwmon_curr_crit:
1262 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
1263 		sfp_hwmon_calibrate_bias(sfp, value);
1264 		return 0;
1265 
1266 	case hwmon_curr_lcrit_alarm:
1267 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1268 		if (err < 0)
1269 			return err;
1270 
1271 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
1272 		return 0;
1273 
1274 	case hwmon_curr_min_alarm:
1275 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1276 		if (err < 0)
1277 			return err;
1278 
1279 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
1280 		return 0;
1281 
1282 	case hwmon_curr_max_alarm:
1283 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1284 		if (err < 0)
1285 			return err;
1286 
1287 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
1288 		return 0;
1289 
1290 	case hwmon_curr_crit_alarm:
1291 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1292 		if (err < 0)
1293 			return err;
1294 
1295 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
1296 		return 0;
1297 	default:
1298 		return -EOPNOTSUPP;
1299 	}
1300 
1301 	return -EOPNOTSUPP;
1302 }
1303 
1304 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
1305 {
1306 	u8 status;
1307 	int err;
1308 
1309 	switch (attr) {
1310 	case hwmon_power_input:
1311 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
1312 
1313 	case hwmon_power_lcrit:
1314 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
1315 		sfp_hwmon_calibrate_tx_power(sfp, value);
1316 		return 0;
1317 
1318 	case hwmon_power_min:
1319 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
1320 		sfp_hwmon_calibrate_tx_power(sfp, value);
1321 		return 0;
1322 
1323 	case hwmon_power_max:
1324 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
1325 		sfp_hwmon_calibrate_tx_power(sfp, value);
1326 		return 0;
1327 
1328 	case hwmon_power_crit:
1329 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
1330 		sfp_hwmon_calibrate_tx_power(sfp, value);
1331 		return 0;
1332 
1333 	case hwmon_power_lcrit_alarm:
1334 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1335 		if (err < 0)
1336 			return err;
1337 
1338 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
1339 		return 0;
1340 
1341 	case hwmon_power_min_alarm:
1342 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1343 		if (err < 0)
1344 			return err;
1345 
1346 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
1347 		return 0;
1348 
1349 	case hwmon_power_max_alarm:
1350 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1351 		if (err < 0)
1352 			return err;
1353 
1354 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1355 		return 0;
1356 
1357 	case hwmon_power_crit_alarm:
1358 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1359 		if (err < 0)
1360 			return err;
1361 
1362 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1363 		return 0;
1364 	default:
1365 		return -EOPNOTSUPP;
1366 	}
1367 
1368 	return -EOPNOTSUPP;
1369 }
1370 
1371 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1372 {
1373 	u8 status;
1374 	int err;
1375 
1376 	switch (attr) {
1377 	case hwmon_power_input:
1378 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1379 
1380 	case hwmon_power_lcrit:
1381 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1382 		sfp_hwmon_to_rx_power(value);
1383 		return 0;
1384 
1385 	case hwmon_power_min:
1386 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1387 		sfp_hwmon_to_rx_power(value);
1388 		return 0;
1389 
1390 	case hwmon_power_max:
1391 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1392 		sfp_hwmon_to_rx_power(value);
1393 		return 0;
1394 
1395 	case hwmon_power_crit:
1396 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1397 		sfp_hwmon_to_rx_power(value);
1398 		return 0;
1399 
1400 	case hwmon_power_lcrit_alarm:
1401 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1402 		if (err < 0)
1403 			return err;
1404 
1405 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1406 		return 0;
1407 
1408 	case hwmon_power_min_alarm:
1409 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1410 		if (err < 0)
1411 			return err;
1412 
1413 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1414 		return 0;
1415 
1416 	case hwmon_power_max_alarm:
1417 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1418 		if (err < 0)
1419 			return err;
1420 
1421 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1422 		return 0;
1423 
1424 	case hwmon_power_crit_alarm:
1425 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1426 		if (err < 0)
1427 			return err;
1428 
1429 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1430 		return 0;
1431 	default:
1432 		return -EOPNOTSUPP;
1433 	}
1434 
1435 	return -EOPNOTSUPP;
1436 }
1437 
1438 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1439 			  u32 attr, int channel, long *value)
1440 {
1441 	struct sfp *sfp = dev_get_drvdata(dev);
1442 
1443 	switch (type) {
1444 	case hwmon_temp:
1445 		return sfp_hwmon_temp(sfp, attr, value);
1446 	case hwmon_in:
1447 		return sfp_hwmon_vcc(sfp, attr, value);
1448 	case hwmon_curr:
1449 		return sfp_hwmon_bias(sfp, attr, value);
1450 	case hwmon_power:
1451 		switch (channel) {
1452 		case 0:
1453 			return sfp_hwmon_tx_power(sfp, attr, value);
1454 		case 1:
1455 			return sfp_hwmon_rx_power(sfp, attr, value);
1456 		default:
1457 			return -EOPNOTSUPP;
1458 		}
1459 	default:
1460 		return -EOPNOTSUPP;
1461 	}
1462 }
1463 
1464 static const char *const sfp_hwmon_power_labels[] = {
1465 	"TX_power",
1466 	"RX_power",
1467 };
1468 
1469 static int sfp_hwmon_read_string(struct device *dev,
1470 				 enum hwmon_sensor_types type,
1471 				 u32 attr, int channel, const char **str)
1472 {
1473 	switch (type) {
1474 	case hwmon_curr:
1475 		switch (attr) {
1476 		case hwmon_curr_label:
1477 			*str = "bias";
1478 			return 0;
1479 		default:
1480 			return -EOPNOTSUPP;
1481 		}
1482 		break;
1483 	case hwmon_temp:
1484 		switch (attr) {
1485 		case hwmon_temp_label:
1486 			*str = "temperature";
1487 			return 0;
1488 		default:
1489 			return -EOPNOTSUPP;
1490 		}
1491 		break;
1492 	case hwmon_in:
1493 		switch (attr) {
1494 		case hwmon_in_label:
1495 			*str = "VCC";
1496 			return 0;
1497 		default:
1498 			return -EOPNOTSUPP;
1499 		}
1500 		break;
1501 	case hwmon_power:
1502 		switch (attr) {
1503 		case hwmon_power_label:
1504 			*str = sfp_hwmon_power_labels[channel];
1505 			return 0;
1506 		default:
1507 			return -EOPNOTSUPP;
1508 		}
1509 		break;
1510 	default:
1511 		return -EOPNOTSUPP;
1512 	}
1513 
1514 	return -EOPNOTSUPP;
1515 }
1516 
1517 static const struct hwmon_ops sfp_hwmon_ops = {
1518 	.is_visible = sfp_hwmon_is_visible,
1519 	.read = sfp_hwmon_read,
1520 	.read_string = sfp_hwmon_read_string,
1521 };
1522 
1523 static const struct hwmon_channel_info * const sfp_hwmon_info[] = {
1524 	HWMON_CHANNEL_INFO(chip,
1525 			   HWMON_C_REGISTER_TZ),
1526 	HWMON_CHANNEL_INFO(in,
1527 			   HWMON_I_INPUT |
1528 			   HWMON_I_MAX | HWMON_I_MIN |
1529 			   HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1530 			   HWMON_I_CRIT | HWMON_I_LCRIT |
1531 			   HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1532 			   HWMON_I_LABEL),
1533 	HWMON_CHANNEL_INFO(temp,
1534 			   HWMON_T_INPUT |
1535 			   HWMON_T_MAX | HWMON_T_MIN |
1536 			   HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1537 			   HWMON_T_CRIT | HWMON_T_LCRIT |
1538 			   HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1539 			   HWMON_T_LABEL),
1540 	HWMON_CHANNEL_INFO(curr,
1541 			   HWMON_C_INPUT |
1542 			   HWMON_C_MAX | HWMON_C_MIN |
1543 			   HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1544 			   HWMON_C_CRIT | HWMON_C_LCRIT |
1545 			   HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1546 			   HWMON_C_LABEL),
1547 	HWMON_CHANNEL_INFO(power,
1548 			   /* Transmit power */
1549 			   HWMON_P_INPUT |
1550 			   HWMON_P_MAX | HWMON_P_MIN |
1551 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1552 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1553 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1554 			   HWMON_P_LABEL,
1555 			   /* Receive power */
1556 			   HWMON_P_INPUT |
1557 			   HWMON_P_MAX | HWMON_P_MIN |
1558 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1559 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1560 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1561 			   HWMON_P_LABEL),
1562 	NULL,
1563 };
1564 
1565 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1566 	.ops = &sfp_hwmon_ops,
1567 	.info = sfp_hwmon_info,
1568 };
1569 
1570 static void sfp_hwmon_probe(struct work_struct *work)
1571 {
1572 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1573 	int err;
1574 
1575 	/* hwmon interface needs to access 16bit registers in atomic way to
1576 	 * guarantee coherency of the diagnostic monitoring data. If it is not
1577 	 * possible to guarantee coherency because EEPROM is broken in such way
1578 	 * that does not support atomic 16bit read operation then we have to
1579 	 * skip registration of hwmon device.
1580 	 */
1581 	if (sfp->i2c_block_size < 2) {
1582 		dev_info(sfp->dev,
1583 			 "skipping hwmon device registration due to broken EEPROM\n");
1584 		dev_info(sfp->dev,
1585 			 "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
1586 		return;
1587 	}
1588 
1589 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1590 	if (err < 0) {
1591 		if (sfp->hwmon_tries--) {
1592 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1593 					 T_PROBE_RETRY_SLOW);
1594 		} else {
1595 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
1596 				 ERR_PTR(err));
1597 		}
1598 		return;
1599 	}
1600 
1601 	sfp->hwmon_name = hwmon_sanitize_name(dev_name(sfp->dev));
1602 	if (IS_ERR(sfp->hwmon_name)) {
1603 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1604 		return;
1605 	}
1606 
1607 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1608 							 sfp->hwmon_name, sfp,
1609 							 &sfp_hwmon_chip_info,
1610 							 NULL);
1611 	if (IS_ERR(sfp->hwmon_dev))
1612 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1613 			PTR_ERR(sfp->hwmon_dev));
1614 }
1615 
1616 static int sfp_hwmon_insert(struct sfp *sfp)
1617 {
1618 	if (sfp->have_a2 && sfp->id.ext.diagmon & SFP_DIAGMON_DDM) {
1619 		mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1620 		sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1621 	}
1622 
1623 	return 0;
1624 }
1625 
1626 static void sfp_hwmon_remove(struct sfp *sfp)
1627 {
1628 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1629 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1630 		hwmon_device_unregister(sfp->hwmon_dev);
1631 		sfp->hwmon_dev = NULL;
1632 		kfree(sfp->hwmon_name);
1633 	}
1634 }
1635 
1636 static int sfp_hwmon_init(struct sfp *sfp)
1637 {
1638 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1639 
1640 	return 0;
1641 }
1642 
1643 static void sfp_hwmon_exit(struct sfp *sfp)
1644 {
1645 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1646 }
1647 #else
1648 static int sfp_hwmon_insert(struct sfp *sfp)
1649 {
1650 	return 0;
1651 }
1652 
1653 static void sfp_hwmon_remove(struct sfp *sfp)
1654 {
1655 }
1656 
1657 static int sfp_hwmon_init(struct sfp *sfp)
1658 {
1659 	return 0;
1660 }
1661 
1662 static void sfp_hwmon_exit(struct sfp *sfp)
1663 {
1664 }
1665 #endif
1666 
1667 /* Helpers */
1668 static void sfp_module_tx_disable(struct sfp *sfp)
1669 {
1670 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1671 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1672 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, SFP_F_TX_DISABLE);
1673 }
1674 
1675 static void sfp_module_tx_enable(struct sfp *sfp)
1676 {
1677 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1678 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1679 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, 0);
1680 }
1681 
1682 #if IS_ENABLED(CONFIG_DEBUG_FS)
1683 static int sfp_debug_state_show(struct seq_file *s, void *data)
1684 {
1685 	struct sfp *sfp = s->private;
1686 
1687 	seq_printf(s, "Module state: %s\n",
1688 		   mod_state_to_str(sfp->sm_mod_state));
1689 	seq_printf(s, "Module probe attempts: %d %d\n",
1690 		   R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
1691 		   R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
1692 	seq_printf(s, "Device state: %s\n",
1693 		   dev_state_to_str(sfp->sm_dev_state));
1694 	seq_printf(s, "Main state: %s\n",
1695 		   sm_state_to_str(sfp->sm_state));
1696 	seq_printf(s, "Fault recovery remaining retries: %d\n",
1697 		   sfp->sm_fault_retries);
1698 	seq_printf(s, "PHY probe remaining retries: %d\n",
1699 		   sfp->sm_phy_retries);
1700 	seq_printf(s, "Signalling rate: %u kBd\n", sfp->rate_kbd);
1701 	seq_printf(s, "Rate select threshold: %u kBd\n",
1702 		   sfp->rs_threshold_kbd);
1703 	seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
1704 	seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
1705 	seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
1706 	seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
1707 	seq_printf(s, "rs0: %d\n", !!(sfp->state & SFP_F_RS0));
1708 	seq_printf(s, "rs1: %d\n", !!(sfp->state & SFP_F_RS1));
1709 	return 0;
1710 }
1711 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
1712 
1713 static void sfp_debugfs_init(struct sfp *sfp)
1714 {
1715 	sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
1716 
1717 	debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
1718 			    &sfp_debug_state_fops);
1719 }
1720 
1721 static void sfp_debugfs_exit(struct sfp *sfp)
1722 {
1723 	debugfs_remove_recursive(sfp->debugfs_dir);
1724 }
1725 #else
1726 static void sfp_debugfs_init(struct sfp *sfp)
1727 {
1728 }
1729 
1730 static void sfp_debugfs_exit(struct sfp *sfp)
1731 {
1732 }
1733 #endif
1734 
1735 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1736 {
1737 	unsigned int state;
1738 
1739 	mutex_lock(&sfp->st_mutex);
1740 	state = sfp->state;
1741 	if (!(state & SFP_F_TX_DISABLE)) {
1742 		sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1743 
1744 		udelay(T_RESET_US);
1745 
1746 		sfp_set_state(sfp, state);
1747 	}
1748 	mutex_unlock(&sfp->st_mutex);
1749 }
1750 
1751 /* SFP state machine */
1752 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1753 {
1754 	if (timeout)
1755 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1756 				 timeout);
1757 	else
1758 		cancel_delayed_work(&sfp->timeout);
1759 }
1760 
1761 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1762 			unsigned int timeout)
1763 {
1764 	sfp->sm_state = state;
1765 	sfp_sm_set_timer(sfp, timeout);
1766 }
1767 
1768 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1769 			    unsigned int timeout)
1770 {
1771 	sfp->sm_mod_state = state;
1772 	sfp_sm_set_timer(sfp, timeout);
1773 }
1774 
1775 static void sfp_sm_phy_detach(struct sfp *sfp)
1776 {
1777 	sfp_remove_phy(sfp->sfp_bus);
1778 	phy_device_remove(sfp->mod_phy);
1779 	phy_device_free(sfp->mod_phy);
1780 	sfp->mod_phy = NULL;
1781 }
1782 
1783 static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
1784 {
1785 	struct phy_device *phy;
1786 	int err;
1787 
1788 	phy = get_phy_device(sfp->i2c_mii, addr, is_c45);
1789 	if (phy == ERR_PTR(-ENODEV))
1790 		return PTR_ERR(phy);
1791 	if (IS_ERR(phy)) {
1792 		dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
1793 		return PTR_ERR(phy);
1794 	}
1795 
1796 	/* Mark this PHY as being on a SFP module */
1797 	phy->is_on_sfp_module = true;
1798 
1799 	err = phy_device_register(phy);
1800 	if (err) {
1801 		phy_device_free(phy);
1802 		dev_err(sfp->dev, "phy_device_register failed: %pe\n",
1803 			ERR_PTR(err));
1804 		return err;
1805 	}
1806 
1807 	err = sfp_add_phy(sfp->sfp_bus, phy);
1808 	if (err) {
1809 		phy_device_remove(phy);
1810 		phy_device_free(phy);
1811 		dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
1812 		return err;
1813 	}
1814 
1815 	sfp->mod_phy = phy;
1816 
1817 	return 0;
1818 }
1819 
1820 static void sfp_sm_link_up(struct sfp *sfp)
1821 {
1822 	sfp_link_up(sfp->sfp_bus);
1823 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1824 }
1825 
1826 static void sfp_sm_link_down(struct sfp *sfp)
1827 {
1828 	sfp_link_down(sfp->sfp_bus);
1829 }
1830 
1831 static void sfp_sm_link_check_los(struct sfp *sfp)
1832 {
1833 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1834 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1835 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1836 	bool los = false;
1837 
1838 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1839 	 * are set, we assume that no LOS signal is available. If both are
1840 	 * set, we assume LOS is not implemented (and is meaningless.)
1841 	 */
1842 	if (los_options == los_inverted)
1843 		los = !(sfp->state & SFP_F_LOS);
1844 	else if (los_options == los_normal)
1845 		los = !!(sfp->state & SFP_F_LOS);
1846 
1847 	if (los)
1848 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1849 	else
1850 		sfp_sm_link_up(sfp);
1851 }
1852 
1853 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1854 {
1855 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1856 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1857 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1858 
1859 	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
1860 	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
1861 }
1862 
1863 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1864 {
1865 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1866 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1867 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1868 
1869 	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
1870 	       (los_options == los_normal && event == SFP_E_LOS_LOW);
1871 }
1872 
1873 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1874 {
1875 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
1876 		dev_err(sfp->dev,
1877 			"module persistently indicates fault, disabling\n");
1878 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1879 	} else {
1880 		if (warn)
1881 			dev_err(sfp->dev, "module transmit fault indicated\n");
1882 
1883 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1884 	}
1885 }
1886 
1887 static int sfp_sm_add_mdio_bus(struct sfp *sfp)
1888 {
1889 	if (sfp->mdio_protocol != MDIO_I2C_NONE)
1890 		return sfp_i2c_mdiobus_create(sfp);
1891 
1892 	return 0;
1893 }
1894 
1895 /* Probe a SFP for a PHY device if the module supports copper - the PHY
1896  * normally sits at I2C bus address 0x56, and may either be a clause 22
1897  * or clause 45 PHY.
1898  *
1899  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
1900  * negotiation enabled, but some may be in 1000base-X - which is for the
1901  * PHY driver to determine.
1902  *
1903  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
1904  * mode according to the negotiated line speed.
1905  */
1906 static int sfp_sm_probe_for_phy(struct sfp *sfp)
1907 {
1908 	int err = 0;
1909 
1910 	switch (sfp->mdio_protocol) {
1911 	case MDIO_I2C_NONE:
1912 		break;
1913 
1914 	case MDIO_I2C_MARVELL_C22:
1915 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, false);
1916 		break;
1917 
1918 	case MDIO_I2C_C45:
1919 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, true);
1920 		break;
1921 
1922 	case MDIO_I2C_ROLLBALL:
1923 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR_ROLLBALL, true);
1924 		break;
1925 	}
1926 
1927 	return err;
1928 }
1929 
1930 static int sfp_module_parse_power(struct sfp *sfp)
1931 {
1932 	u32 power_mW = 1000;
1933 	bool supports_a2;
1934 
1935 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
1936 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1937 		power_mW = 1500;
1938 	/* Added in Rev 11.9, but there is no compliance code for this */
1939 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV11_4 &&
1940 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1941 		power_mW = 2000;
1942 
1943 	/* Power level 1 modules (max. 1W) are always supported. */
1944 	if (power_mW <= 1000) {
1945 		sfp->module_power_mW = power_mW;
1946 		return 0;
1947 	}
1948 
1949 	supports_a2 = sfp->id.ext.sff8472_compliance !=
1950 				SFP_SFF8472_COMPLIANCE_NONE ||
1951 		      sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
1952 
1953 	if (power_mW > sfp->max_power_mW) {
1954 		/* Module power specification exceeds the allowed maximum. */
1955 		if (!supports_a2) {
1956 			/* The module appears not to implement bus address
1957 			 * 0xa2, so assume that the module powers up in the
1958 			 * indicated mode.
1959 			 */
1960 			dev_err(sfp->dev,
1961 				"Host does not support %u.%uW modules\n",
1962 				power_mW / 1000, (power_mW / 100) % 10);
1963 			return -EINVAL;
1964 		} else {
1965 			dev_warn(sfp->dev,
1966 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1967 				 power_mW / 1000, (power_mW / 100) % 10);
1968 			return 0;
1969 		}
1970 	}
1971 
1972 	if (!supports_a2) {
1973 		/* The module power level is below the host maximum and the
1974 		 * module appears not to implement bus address 0xa2, so assume
1975 		 * that the module powers up in the indicated mode.
1976 		 */
1977 		return 0;
1978 	}
1979 
1980 	/* If the module requires a higher power mode, but also requires
1981 	 * an address change sequence, warn the user that the module may
1982 	 * not be functional.
1983 	 */
1984 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
1985 		dev_warn(sfp->dev,
1986 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1987 			 power_mW / 1000, (power_mW / 100) % 10);
1988 		return 0;
1989 	}
1990 
1991 	sfp->module_power_mW = power_mW;
1992 
1993 	return 0;
1994 }
1995 
1996 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1997 {
1998 	int err;
1999 
2000 	err = sfp_modify_u8(sfp, true, SFP_EXT_STATUS,
2001 			    SFP_EXT_STATUS_PWRLVL_SELECT,
2002 			    enable ? SFP_EXT_STATUS_PWRLVL_SELECT : 0);
2003 	if (err != sizeof(u8)) {
2004 		dev_err(sfp->dev, "failed to %sable high power: %pe\n",
2005 			enable ? "en" : "dis", ERR_PTR(err));
2006 		return -EAGAIN;
2007 	}
2008 
2009 	if (enable)
2010 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
2011 			 sfp->module_power_mW / 1000,
2012 			 (sfp->module_power_mW / 100) % 10);
2013 
2014 	return 0;
2015 }
2016 
2017 static void sfp_module_parse_rate_select(struct sfp *sfp)
2018 {
2019 	u8 rate_id;
2020 
2021 	sfp->rs_threshold_kbd = 0;
2022 	sfp->rs_state_mask = 0;
2023 
2024 	if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_RATE_SELECT)))
2025 		/* No support for RateSelect */
2026 		return;
2027 
2028 	/* Default to INF-8074 RateSelect operation. The signalling threshold
2029 	 * rate is not well specified, so always select "Full Bandwidth", but
2030 	 * SFF-8079 reveals that it is understood that RS0 will be low for
2031 	 * 1.0625Gb/s and high for 2.125Gb/s. Choose a value half-way between.
2032 	 * This method exists prior to SFF-8472.
2033 	 */
2034 	sfp->rs_state_mask = SFP_F_RS0;
2035 	sfp->rs_threshold_kbd = 1594;
2036 
2037 	/* Parse the rate identifier, which is complicated due to history:
2038 	 * SFF-8472 rev 9.5 marks this field as reserved.
2039 	 * SFF-8079 references SFF-8472 rev 9.5 and defines bit 0. SFF-8472
2040 	 *  compliance is not required.
2041 	 * SFF-8472 rev 10.2 defines this field using values 0..4
2042 	 * SFF-8472 rev 11.0 redefines this field with bit 0 for SFF-8079
2043 	 * and even values.
2044 	 */
2045 	rate_id = sfp->id.base.rate_id;
2046 	if (rate_id == 0)
2047 		/* Unspecified */
2048 		return;
2049 
2050 	/* SFF-8472 rev 10.0..10.4 did not account for SFF-8079 using bit 0,
2051 	 * and allocated value 3 to SFF-8431 independent tx/rx rate select.
2052 	 * Convert this to a SFF-8472 rev 11.0 rate identifier.
2053 	 */
2054 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
2055 	    sfp->id.ext.sff8472_compliance < SFP_SFF8472_COMPLIANCE_REV11_0 &&
2056 	    rate_id == 3)
2057 		rate_id = SFF_RID_8431;
2058 
2059 	if (rate_id & SFF_RID_8079) {
2060 		/* SFF-8079 RateSelect / Application Select in conjunction with
2061 		 * SFF-8472 rev 9.5. SFF-8079 defines rate_id as a bitfield
2062 		 * with only bit 0 used, which takes precedence over SFF-8472.
2063 		 */
2064 		if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_APP_SELECT_SFF8079)) {
2065 			/* SFF-8079 Part 1 - rate selection between Fibre
2066 			 * Channel 1.0625/2.125/4.25 Gbd modes. Note that RS0
2067 			 * is high for 2125, so we have to subtract 1 to
2068 			 * include it.
2069 			 */
2070 			sfp->rs_threshold_kbd = 2125 - 1;
2071 			sfp->rs_state_mask = SFP_F_RS0;
2072 		}
2073 		return;
2074 	}
2075 
2076 	/* SFF-8472 rev 9.5 does not define the rate identifier */
2077 	if (sfp->id.ext.sff8472_compliance <= SFP_SFF8472_COMPLIANCE_REV9_5)
2078 		return;
2079 
2080 	/* SFF-8472 rev 11.0 defines rate_id as a numerical value which will
2081 	 * always have bit 0 clear due to SFF-8079's bitfield usage of rate_id.
2082 	 */
2083 	switch (rate_id) {
2084 	case SFF_RID_8431_RX_ONLY:
2085 		sfp->rs_threshold_kbd = 4250;
2086 		sfp->rs_state_mask = SFP_F_RS0;
2087 		break;
2088 
2089 	case SFF_RID_8431_TX_ONLY:
2090 		sfp->rs_threshold_kbd = 4250;
2091 		sfp->rs_state_mask = SFP_F_RS1;
2092 		break;
2093 
2094 	case SFF_RID_8431:
2095 		sfp->rs_threshold_kbd = 4250;
2096 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2097 		break;
2098 
2099 	case SFF_RID_10G8G:
2100 		sfp->rs_threshold_kbd = 9000;
2101 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2102 		break;
2103 	}
2104 }
2105 
2106 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
2107  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
2108  * not support multibyte reads from the EEPROM. Each multi-byte read
2109  * operation returns just one byte of EEPROM followed by zeros. There is
2110  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
2111  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
2112  * name and vendor id into EEPROM, so there is even no way to detect if
2113  * module is V-SOL V2801F. Therefore check for those zeros in the read
2114  * data and then based on check switch to reading EEPROM to one byte
2115  * at a time.
2116  */
2117 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
2118 {
2119 	size_t i, block_size = sfp->i2c_block_size;
2120 
2121 	/* Already using byte IO */
2122 	if (block_size == 1)
2123 		return false;
2124 
2125 	for (i = 1; i < len; i += block_size) {
2126 		if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
2127 			return false;
2128 	}
2129 	return true;
2130 }
2131 
2132 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
2133 {
2134 	u8 check;
2135 	int err;
2136 
2137 	if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
2138 	    id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
2139 	    id->base.connector != SFF8024_CONNECTOR_LC) {
2140 		dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
2141 		id->base.phys_id = SFF8024_ID_SFF_8472;
2142 		id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
2143 		id->base.connector = SFF8024_CONNECTOR_LC;
2144 		err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
2145 		if (err != 3) {
2146 			dev_err(sfp->dev,
2147 				"Failed to rewrite module EEPROM: %pe\n",
2148 				ERR_PTR(err));
2149 			return err;
2150 		}
2151 
2152 		/* Cotsworks modules have been found to require a delay between write operations. */
2153 		mdelay(50);
2154 
2155 		/* Update base structure checksum */
2156 		check = sfp_check(&id->base, sizeof(id->base) - 1);
2157 		err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
2158 		if (err != 1) {
2159 			dev_err(sfp->dev,
2160 				"Failed to update base structure checksum in fiber module EEPROM: %pe\n",
2161 				ERR_PTR(err));
2162 			return err;
2163 		}
2164 	}
2165 	return 0;
2166 }
2167 
2168 static int sfp_module_parse_sff8472(struct sfp *sfp)
2169 {
2170 	/* If the module requires address swap mode, warn about it */
2171 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
2172 		dev_warn(sfp->dev,
2173 			 "module address swap to access page 0xA2 is not supported.\n");
2174 	else
2175 		sfp->have_a2 = true;
2176 
2177 	return 0;
2178 }
2179 
2180 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
2181 {
2182 	/* SFP module inserted - read I2C data */
2183 	struct sfp_eeprom_id id;
2184 	bool cotsworks_sfbg;
2185 	unsigned int mask;
2186 	bool cotsworks;
2187 	u8 check;
2188 	int ret;
2189 
2190 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2191 
2192 	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2193 	if (ret < 0) {
2194 		if (report)
2195 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2196 				ERR_PTR(ret));
2197 		return -EAGAIN;
2198 	}
2199 
2200 	if (ret != sizeof(id.base)) {
2201 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2202 		return -EAGAIN;
2203 	}
2204 
2205 	/* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
2206 	 * address 0x51 is just one byte at a time. Also SFF-8472 requires
2207 	 * that EEPROM supports atomic 16bit read operation for diagnostic
2208 	 * fields, so do not switch to one byte reading at a time unless it
2209 	 * is really required and we have no other option.
2210 	 */
2211 	if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
2212 		dev_info(sfp->dev,
2213 			 "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
2214 		dev_info(sfp->dev,
2215 			 "Switching to reading EEPROM to one byte at a time\n");
2216 		sfp->i2c_block_size = 1;
2217 
2218 		ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2219 		if (ret < 0) {
2220 			if (report)
2221 				dev_err(sfp->dev,
2222 					"failed to read EEPROM: %pe\n",
2223 					ERR_PTR(ret));
2224 			return -EAGAIN;
2225 		}
2226 
2227 		if (ret != sizeof(id.base)) {
2228 			dev_err(sfp->dev, "EEPROM short read: %pe\n",
2229 				ERR_PTR(ret));
2230 			return -EAGAIN;
2231 		}
2232 	}
2233 
2234 	/* Cotsworks do not seem to update the checksums when they
2235 	 * do the final programming with the final module part number,
2236 	 * serial number and date code.
2237 	 */
2238 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
2239 	cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
2240 
2241 	/* Cotsworks SFF module EEPROM do not always have valid phys_id,
2242 	 * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
2243 	 * Cotsworks PN matches and bytes are not correct.
2244 	 */
2245 	if (cotsworks && cotsworks_sfbg) {
2246 		ret = sfp_cotsworks_fixup_check(sfp, &id);
2247 		if (ret < 0)
2248 			return ret;
2249 	}
2250 
2251 	/* Validate the checksum over the base structure */
2252 	check = sfp_check(&id.base, sizeof(id.base) - 1);
2253 	if (check != id.base.cc_base) {
2254 		if (cotsworks) {
2255 			dev_warn(sfp->dev,
2256 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
2257 				 check, id.base.cc_base);
2258 		} else {
2259 			dev_err(sfp->dev,
2260 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
2261 				check, id.base.cc_base);
2262 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2263 				       16, 1, &id, sizeof(id), true);
2264 			return -EINVAL;
2265 		}
2266 	}
2267 
2268 	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
2269 	if (ret < 0) {
2270 		if (report)
2271 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2272 				ERR_PTR(ret));
2273 		return -EAGAIN;
2274 	}
2275 
2276 	if (ret != sizeof(id.ext)) {
2277 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2278 		return -EAGAIN;
2279 	}
2280 
2281 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
2282 	if (check != id.ext.cc_ext) {
2283 		if (cotsworks) {
2284 			dev_warn(sfp->dev,
2285 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
2286 				 check, id.ext.cc_ext);
2287 		} else {
2288 			dev_err(sfp->dev,
2289 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
2290 				check, id.ext.cc_ext);
2291 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2292 				       16, 1, &id, sizeof(id), true);
2293 			memset(&id.ext, 0, sizeof(id.ext));
2294 		}
2295 	}
2296 
2297 	sfp->id = id;
2298 
2299 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
2300 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
2301 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
2302 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
2303 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
2304 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
2305 
2306 	/* Check whether we support this module */
2307 	if (!sfp->type->module_supported(&id)) {
2308 		dev_err(sfp->dev,
2309 			"module is not supported - phys id 0x%02x 0x%02x\n",
2310 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
2311 		return -EINVAL;
2312 	}
2313 
2314 	if (sfp->id.ext.sff8472_compliance != SFP_SFF8472_COMPLIANCE_NONE) {
2315 		ret = sfp_module_parse_sff8472(sfp);
2316 		if (ret < 0)
2317 			return ret;
2318 	}
2319 
2320 	/* Parse the module power requirement */
2321 	ret = sfp_module_parse_power(sfp);
2322 	if (ret < 0)
2323 		return ret;
2324 
2325 	sfp_module_parse_rate_select(sfp);
2326 
2327 	mask = SFP_F_PRESENT;
2328 	if (sfp->gpio[GPIO_TX_DISABLE])
2329 		mask |= SFP_F_TX_DISABLE;
2330 	if (sfp->gpio[GPIO_TX_FAULT])
2331 		mask |= SFP_F_TX_FAULT;
2332 	if (sfp->gpio[GPIO_LOS])
2333 		mask |= SFP_F_LOS;
2334 	if (sfp->gpio[GPIO_RS0])
2335 		mask |= SFP_F_RS0;
2336 	if (sfp->gpio[GPIO_RS1])
2337 		mask |= SFP_F_RS1;
2338 
2339 	sfp->module_t_start_up = T_START_UP;
2340 	sfp->module_t_wait = T_WAIT;
2341 	sfp->phy_t_retry = T_PHY_RETRY;
2342 
2343 	sfp->state_ignore_mask = 0;
2344 
2345 	if (sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SFI ||
2346 	    sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SR ||
2347 	    sfp->id.base.extended_cc == SFF8024_ECC_5GBASE_T ||
2348 	    sfp->id.base.extended_cc == SFF8024_ECC_2_5GBASE_T)
2349 		sfp->mdio_protocol = MDIO_I2C_C45;
2350 	else if (sfp->id.base.e1000_base_t)
2351 		sfp->mdio_protocol = MDIO_I2C_MARVELL_C22;
2352 	else
2353 		sfp->mdio_protocol = MDIO_I2C_NONE;
2354 
2355 	sfp->quirk = sfp_lookup_quirk(&id);
2356 
2357 	mutex_lock(&sfp->st_mutex);
2358 	/* Initialise state bits to use from hardware */
2359 	sfp->state_hw_mask = mask;
2360 
2361 	/* We want to drive the rate select pins that the module is using */
2362 	sfp->state_hw_drive |= sfp->rs_state_mask;
2363 
2364 	if (sfp->quirk && sfp->quirk->fixup)
2365 		sfp->quirk->fixup(sfp);
2366 
2367 	sfp->state_hw_mask &= ~sfp->state_ignore_mask;
2368 	mutex_unlock(&sfp->st_mutex);
2369 
2370 	return 0;
2371 }
2372 
2373 static void sfp_sm_mod_remove(struct sfp *sfp)
2374 {
2375 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
2376 		sfp_module_remove(sfp->sfp_bus);
2377 
2378 	sfp_hwmon_remove(sfp);
2379 
2380 	memset(&sfp->id, 0, sizeof(sfp->id));
2381 	sfp->module_power_mW = 0;
2382 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
2383 	sfp->have_a2 = false;
2384 
2385 	dev_info(sfp->dev, "module removed\n");
2386 }
2387 
2388 /* This state machine tracks the upstream's state */
2389 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
2390 {
2391 	switch (sfp->sm_dev_state) {
2392 	default:
2393 		if (event == SFP_E_DEV_ATTACH)
2394 			sfp->sm_dev_state = SFP_DEV_DOWN;
2395 		break;
2396 
2397 	case SFP_DEV_DOWN:
2398 		if (event == SFP_E_DEV_DETACH)
2399 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2400 		else if (event == SFP_E_DEV_UP)
2401 			sfp->sm_dev_state = SFP_DEV_UP;
2402 		break;
2403 
2404 	case SFP_DEV_UP:
2405 		if (event == SFP_E_DEV_DETACH)
2406 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2407 		else if (event == SFP_E_DEV_DOWN)
2408 			sfp->sm_dev_state = SFP_DEV_DOWN;
2409 		break;
2410 	}
2411 }
2412 
2413 /* This state machine tracks the insert/remove state of the module, probes
2414  * the on-board EEPROM, and sets up the power level.
2415  */
2416 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
2417 {
2418 	int err;
2419 
2420 	/* Handle remove event globally, it resets this state machine */
2421 	if (event == SFP_E_REMOVE) {
2422 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
2423 			sfp_sm_mod_remove(sfp);
2424 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
2425 		return;
2426 	}
2427 
2428 	/* Handle device detach globally */
2429 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
2430 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
2431 		if (sfp->module_power_mW > 1000 &&
2432 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
2433 			sfp_sm_mod_hpower(sfp, false);
2434 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2435 		return;
2436 	}
2437 
2438 	switch (sfp->sm_mod_state) {
2439 	default:
2440 		if (event == SFP_E_INSERT) {
2441 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
2442 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
2443 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
2444 		}
2445 		break;
2446 
2447 	case SFP_MOD_PROBE:
2448 		/* Wait for T_PROBE_INIT to time out */
2449 		if (event != SFP_E_TIMEOUT)
2450 			break;
2451 
2452 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
2453 		if (err == -EAGAIN) {
2454 			if (sfp->sm_mod_tries_init &&
2455 			   --sfp->sm_mod_tries_init) {
2456 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2457 				break;
2458 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
2459 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
2460 					dev_warn(sfp->dev,
2461 						 "please wait, module slow to respond\n");
2462 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
2463 				break;
2464 			}
2465 		}
2466 		if (err < 0) {
2467 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2468 			break;
2469 		}
2470 
2471 		/* Force a poll to re-read the hardware signal state after
2472 		 * sfp_sm_mod_probe() changed state_hw_mask.
2473 		 */
2474 		mod_delayed_work(system_wq, &sfp->poll, 1);
2475 
2476 		err = sfp_hwmon_insert(sfp);
2477 		if (err)
2478 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
2479 				 ERR_PTR(err));
2480 
2481 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2482 		fallthrough;
2483 	case SFP_MOD_WAITDEV:
2484 		/* Ensure that the device is attached before proceeding */
2485 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
2486 			break;
2487 
2488 		/* Report the module insertion to the upstream device */
2489 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id,
2490 					sfp->quirk);
2491 		if (err < 0) {
2492 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2493 			break;
2494 		}
2495 
2496 		/* If this is a power level 1 module, we are done */
2497 		if (sfp->module_power_mW <= 1000)
2498 			goto insert;
2499 
2500 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
2501 		fallthrough;
2502 	case SFP_MOD_HPOWER:
2503 		/* Enable high power mode */
2504 		err = sfp_sm_mod_hpower(sfp, true);
2505 		if (err < 0) {
2506 			if (err != -EAGAIN) {
2507 				sfp_module_remove(sfp->sfp_bus);
2508 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2509 			} else {
2510 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2511 			}
2512 			break;
2513 		}
2514 
2515 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
2516 		break;
2517 
2518 	case SFP_MOD_WAITPWR:
2519 		/* Wait for T_HPOWER_LEVEL to time out */
2520 		if (event != SFP_E_TIMEOUT)
2521 			break;
2522 
2523 	insert:
2524 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
2525 		break;
2526 
2527 	case SFP_MOD_PRESENT:
2528 	case SFP_MOD_ERROR:
2529 		break;
2530 	}
2531 }
2532 
2533 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
2534 {
2535 	unsigned long timeout;
2536 	int ret;
2537 
2538 	/* Some events are global */
2539 	if (sfp->sm_state != SFP_S_DOWN &&
2540 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2541 	     sfp->sm_dev_state != SFP_DEV_UP)) {
2542 		if (sfp->sm_state == SFP_S_LINK_UP &&
2543 		    sfp->sm_dev_state == SFP_DEV_UP)
2544 			sfp_sm_link_down(sfp);
2545 		if (sfp->sm_state > SFP_S_INIT)
2546 			sfp_module_stop(sfp->sfp_bus);
2547 		if (sfp->mod_phy)
2548 			sfp_sm_phy_detach(sfp);
2549 		if (sfp->i2c_mii)
2550 			sfp_i2c_mdiobus_destroy(sfp);
2551 		sfp_module_tx_disable(sfp);
2552 		sfp_soft_stop_poll(sfp);
2553 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
2554 		return;
2555 	}
2556 
2557 	/* The main state machine */
2558 	switch (sfp->sm_state) {
2559 	case SFP_S_DOWN:
2560 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2561 		    sfp->sm_dev_state != SFP_DEV_UP)
2562 			break;
2563 
2564 		/* Only use the soft state bits if we have access to the A2h
2565 		 * memory, which implies that we have some level of SFF-8472
2566 		 * compliance.
2567 		 */
2568 		if (sfp->have_a2)
2569 			sfp_soft_start_poll(sfp);
2570 
2571 		sfp_module_tx_enable(sfp);
2572 
2573 		/* Initialise the fault clearance retries */
2574 		sfp->sm_fault_retries = N_FAULT_INIT;
2575 
2576 		/* We need to check the TX_FAULT state, which is not defined
2577 		 * while TX_DISABLE is asserted. The earliest we want to do
2578 		 * anything (such as probe for a PHY) is 50ms (or more on
2579 		 * specific modules).
2580 		 */
2581 		sfp_sm_next(sfp, SFP_S_WAIT, sfp->module_t_wait);
2582 		break;
2583 
2584 	case SFP_S_WAIT:
2585 		if (event != SFP_E_TIMEOUT)
2586 			break;
2587 
2588 		if (sfp->state & SFP_F_TX_FAULT) {
2589 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
2590 			 * from the TX_DISABLE deassertion for the module to
2591 			 * initialise, which is indicated by TX_FAULT
2592 			 * deasserting.
2593 			 */
2594 			timeout = sfp->module_t_start_up;
2595 			if (timeout > sfp->module_t_wait)
2596 				timeout -= sfp->module_t_wait;
2597 			else
2598 				timeout = 1;
2599 
2600 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
2601 		} else {
2602 			/* TX_FAULT is not asserted, assume the module has
2603 			 * finished initialising.
2604 			 */
2605 			goto init_done;
2606 		}
2607 		break;
2608 
2609 	case SFP_S_INIT:
2610 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2611 			/* TX_FAULT is still asserted after t_init
2612 			 * or t_start_up, so assume there is a fault.
2613 			 */
2614 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
2615 				     sfp->sm_fault_retries == N_FAULT_INIT);
2616 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2617 	init_done:
2618 			/* Create mdiobus and start trying for PHY */
2619 			ret = sfp_sm_add_mdio_bus(sfp);
2620 			if (ret < 0) {
2621 				sfp_sm_next(sfp, SFP_S_FAIL, 0);
2622 				break;
2623 			}
2624 			sfp->sm_phy_retries = R_PHY_RETRY;
2625 			goto phy_probe;
2626 		}
2627 		break;
2628 
2629 	case SFP_S_INIT_PHY:
2630 		if (event != SFP_E_TIMEOUT)
2631 			break;
2632 	phy_probe:
2633 		/* TX_FAULT deasserted or we timed out with TX_FAULT
2634 		 * clear.  Probe for the PHY and check the LOS state.
2635 		 */
2636 		ret = sfp_sm_probe_for_phy(sfp);
2637 		if (ret == -ENODEV) {
2638 			if (--sfp->sm_phy_retries) {
2639 				sfp_sm_next(sfp, SFP_S_INIT_PHY,
2640 					    sfp->phy_t_retry);
2641 				dev_dbg(sfp->dev,
2642 					"no PHY detected, %u tries left\n",
2643 					sfp->sm_phy_retries);
2644 				break;
2645 			} else {
2646 				dev_info(sfp->dev, "no PHY detected\n");
2647 			}
2648 		} else if (ret) {
2649 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2650 			break;
2651 		}
2652 		if (sfp_module_start(sfp->sfp_bus)) {
2653 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2654 			break;
2655 		}
2656 		sfp_sm_link_check_los(sfp);
2657 
2658 		/* Reset the fault retry count */
2659 		sfp->sm_fault_retries = N_FAULT;
2660 		break;
2661 
2662 	case SFP_S_INIT_TX_FAULT:
2663 		if (event == SFP_E_TIMEOUT) {
2664 			sfp_module_tx_fault_reset(sfp);
2665 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
2666 		}
2667 		break;
2668 
2669 	case SFP_S_WAIT_LOS:
2670 		if (event == SFP_E_TX_FAULT)
2671 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2672 		else if (sfp_los_event_inactive(sfp, event))
2673 			sfp_sm_link_up(sfp);
2674 		break;
2675 
2676 	case SFP_S_LINK_UP:
2677 		if (event == SFP_E_TX_FAULT) {
2678 			sfp_sm_link_down(sfp);
2679 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2680 		} else if (sfp_los_event_active(sfp, event)) {
2681 			sfp_sm_link_down(sfp);
2682 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2683 		}
2684 		break;
2685 
2686 	case SFP_S_TX_FAULT:
2687 		if (event == SFP_E_TIMEOUT) {
2688 			sfp_module_tx_fault_reset(sfp);
2689 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2690 		}
2691 		break;
2692 
2693 	case SFP_S_REINIT:
2694 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2695 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2696 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2697 			dev_info(sfp->dev, "module transmit fault recovered\n");
2698 			sfp_sm_link_check_los(sfp);
2699 		}
2700 		break;
2701 
2702 	case SFP_S_TX_DISABLE:
2703 		break;
2704 	}
2705 }
2706 
2707 static void __sfp_sm_event(struct sfp *sfp, unsigned int event)
2708 {
2709 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
2710 		mod_state_to_str(sfp->sm_mod_state),
2711 		dev_state_to_str(sfp->sm_dev_state),
2712 		sm_state_to_str(sfp->sm_state),
2713 		event_to_str(event));
2714 
2715 	sfp_sm_device(sfp, event);
2716 	sfp_sm_module(sfp, event);
2717 	sfp_sm_main(sfp, event);
2718 
2719 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
2720 		mod_state_to_str(sfp->sm_mod_state),
2721 		dev_state_to_str(sfp->sm_dev_state),
2722 		sm_state_to_str(sfp->sm_state));
2723 }
2724 
2725 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
2726 {
2727 	mutex_lock(&sfp->sm_mutex);
2728 	__sfp_sm_event(sfp, event);
2729 	mutex_unlock(&sfp->sm_mutex);
2730 }
2731 
2732 static void sfp_attach(struct sfp *sfp)
2733 {
2734 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
2735 }
2736 
2737 static void sfp_detach(struct sfp *sfp)
2738 {
2739 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
2740 }
2741 
2742 static void sfp_start(struct sfp *sfp)
2743 {
2744 	sfp_sm_event(sfp, SFP_E_DEV_UP);
2745 }
2746 
2747 static void sfp_stop(struct sfp *sfp)
2748 {
2749 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
2750 }
2751 
2752 static void sfp_set_signal_rate(struct sfp *sfp, unsigned int rate_kbd)
2753 {
2754 	unsigned int set;
2755 
2756 	sfp->rate_kbd = rate_kbd;
2757 
2758 	if (rate_kbd > sfp->rs_threshold_kbd)
2759 		set = sfp->rs_state_mask;
2760 	else
2761 		set = 0;
2762 
2763 	sfp_mod_state(sfp, SFP_F_RS0 | SFP_F_RS1, set);
2764 }
2765 
2766 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2767 {
2768 	/* locking... and check module is present */
2769 
2770 	if (sfp->id.ext.sff8472_compliance &&
2771 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2772 		modinfo->type = ETH_MODULE_SFF_8472;
2773 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2774 	} else {
2775 		modinfo->type = ETH_MODULE_SFF_8079;
2776 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2777 	}
2778 	return 0;
2779 }
2780 
2781 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2782 			     u8 *data)
2783 {
2784 	unsigned int first, last, len;
2785 	int ret;
2786 
2787 	if (!(sfp->state & SFP_F_PRESENT))
2788 		return -ENODEV;
2789 
2790 	if (ee->len == 0)
2791 		return -EINVAL;
2792 
2793 	first = ee->offset;
2794 	last = ee->offset + ee->len;
2795 	if (first < ETH_MODULE_SFF_8079_LEN) {
2796 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2797 		len -= first;
2798 
2799 		ret = sfp_read(sfp, false, first, data, len);
2800 		if (ret < 0)
2801 			return ret;
2802 
2803 		first += len;
2804 		data += len;
2805 	}
2806 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2807 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2808 		len -= first;
2809 		first -= ETH_MODULE_SFF_8079_LEN;
2810 
2811 		ret = sfp_read(sfp, true, first, data, len);
2812 		if (ret < 0)
2813 			return ret;
2814 	}
2815 	return 0;
2816 }
2817 
2818 static int sfp_module_eeprom_by_page(struct sfp *sfp,
2819 				     const struct ethtool_module_eeprom *page,
2820 				     struct netlink_ext_ack *extack)
2821 {
2822 	if (!(sfp->state & SFP_F_PRESENT))
2823 		return -ENODEV;
2824 
2825 	if (page->bank) {
2826 		NL_SET_ERR_MSG(extack, "Banks not supported");
2827 		return -EOPNOTSUPP;
2828 	}
2829 
2830 	if (page->page) {
2831 		NL_SET_ERR_MSG(extack, "Only page 0 supported");
2832 		return -EOPNOTSUPP;
2833 	}
2834 
2835 	if (page->i2c_address != 0x50 &&
2836 	    page->i2c_address != 0x51) {
2837 		NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
2838 		return -EOPNOTSUPP;
2839 	}
2840 
2841 	return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
2842 			page->data, page->length);
2843 };
2844 
2845 static const struct sfp_socket_ops sfp_module_ops = {
2846 	.attach = sfp_attach,
2847 	.detach = sfp_detach,
2848 	.start = sfp_start,
2849 	.stop = sfp_stop,
2850 	.set_signal_rate = sfp_set_signal_rate,
2851 	.module_info = sfp_module_info,
2852 	.module_eeprom = sfp_module_eeprom,
2853 	.module_eeprom_by_page = sfp_module_eeprom_by_page,
2854 };
2855 
2856 static void sfp_timeout(struct work_struct *work)
2857 {
2858 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2859 
2860 	rtnl_lock();
2861 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2862 	rtnl_unlock();
2863 }
2864 
2865 static void sfp_check_state(struct sfp *sfp)
2866 {
2867 	unsigned int state, i, changed;
2868 
2869 	rtnl_lock();
2870 	mutex_lock(&sfp->st_mutex);
2871 	state = sfp_get_state(sfp);
2872 	changed = state ^ sfp->state;
2873 	changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2874 
2875 	for (i = 0; i < GPIO_MAX; i++)
2876 		if (changed & BIT(i))
2877 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_names[i],
2878 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2879 
2880 	state |= sfp->state & SFP_F_OUTPUTS;
2881 	sfp->state = state;
2882 	mutex_unlock(&sfp->st_mutex);
2883 
2884 	mutex_lock(&sfp->sm_mutex);
2885 	if (changed & SFP_F_PRESENT)
2886 		__sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2887 				    SFP_E_INSERT : SFP_E_REMOVE);
2888 
2889 	if (changed & SFP_F_TX_FAULT)
2890 		__sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2891 				    SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2892 
2893 	if (changed & SFP_F_LOS)
2894 		__sfp_sm_event(sfp, state & SFP_F_LOS ?
2895 				    SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2896 	mutex_unlock(&sfp->sm_mutex);
2897 	rtnl_unlock();
2898 }
2899 
2900 static irqreturn_t sfp_irq(int irq, void *data)
2901 {
2902 	struct sfp *sfp = data;
2903 
2904 	sfp_check_state(sfp);
2905 
2906 	return IRQ_HANDLED;
2907 }
2908 
2909 static void sfp_poll(struct work_struct *work)
2910 {
2911 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2912 
2913 	sfp_check_state(sfp);
2914 
2915 	// st_mutex doesn't need to be held here for state_soft_mask,
2916 	// it's unimportant if we race while reading this.
2917 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2918 	    sfp->need_poll)
2919 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2920 }
2921 
2922 static struct sfp *sfp_alloc(struct device *dev)
2923 {
2924 	struct sfp *sfp;
2925 
2926 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2927 	if (!sfp)
2928 		return ERR_PTR(-ENOMEM);
2929 
2930 	sfp->dev = dev;
2931 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2932 
2933 	mutex_init(&sfp->sm_mutex);
2934 	mutex_init(&sfp->st_mutex);
2935 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2936 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2937 
2938 	sfp_hwmon_init(sfp);
2939 
2940 	return sfp;
2941 }
2942 
2943 static void sfp_cleanup(void *data)
2944 {
2945 	struct sfp *sfp = data;
2946 
2947 	sfp_hwmon_exit(sfp);
2948 
2949 	cancel_delayed_work_sync(&sfp->poll);
2950 	cancel_delayed_work_sync(&sfp->timeout);
2951 	if (sfp->i2c_mii) {
2952 		mdiobus_unregister(sfp->i2c_mii);
2953 		mdiobus_free(sfp->i2c_mii);
2954 	}
2955 	if (sfp->i2c)
2956 		i2c_put_adapter(sfp->i2c);
2957 	kfree(sfp);
2958 }
2959 
2960 static int sfp_i2c_get(struct sfp *sfp)
2961 {
2962 	struct fwnode_handle *h;
2963 	struct i2c_adapter *i2c;
2964 	int err;
2965 
2966 	h = fwnode_find_reference(dev_fwnode(sfp->dev), "i2c-bus", 0);
2967 	if (IS_ERR(h)) {
2968 		dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2969 		return -ENODEV;
2970 	}
2971 
2972 	i2c = i2c_get_adapter_by_fwnode(h);
2973 	if (!i2c) {
2974 		err = -EPROBE_DEFER;
2975 		goto put;
2976 	}
2977 
2978 	err = sfp_i2c_configure(sfp, i2c);
2979 	if (err)
2980 		i2c_put_adapter(i2c);
2981 put:
2982 	fwnode_handle_put(h);
2983 	return err;
2984 }
2985 
2986 static int sfp_probe(struct platform_device *pdev)
2987 {
2988 	const struct sff_data *sff;
2989 	char *sfp_irq_name;
2990 	struct sfp *sfp;
2991 	int err, i;
2992 
2993 	sfp = sfp_alloc(&pdev->dev);
2994 	if (IS_ERR(sfp))
2995 		return PTR_ERR(sfp);
2996 
2997 	platform_set_drvdata(pdev, sfp);
2998 
2999 	err = devm_add_action_or_reset(sfp->dev, sfp_cleanup, sfp);
3000 	if (err < 0)
3001 		return err;
3002 
3003 	sff = device_get_match_data(sfp->dev);
3004 	if (!sff)
3005 		sff = &sfp_data;
3006 
3007 	sfp->type = sff;
3008 
3009 	err = sfp_i2c_get(sfp);
3010 	if (err)
3011 		return err;
3012 
3013 	for (i = 0; i < GPIO_MAX; i++)
3014 		if (sff->gpios & BIT(i)) {
3015 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
3016 					   gpio_names[i], gpio_flags[i]);
3017 			if (IS_ERR(sfp->gpio[i]))
3018 				return PTR_ERR(sfp->gpio[i]);
3019 		}
3020 
3021 	sfp->state_hw_mask = SFP_F_PRESENT;
3022 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
3023 
3024 	sfp->get_state = sfp_gpio_get_state;
3025 	sfp->set_state = sfp_gpio_set_state;
3026 
3027 	/* Modules that have no detect signal are always present */
3028 	if (!(sfp->gpio[GPIO_MODDEF0]))
3029 		sfp->get_state = sff_gpio_get_state;
3030 
3031 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
3032 				 &sfp->max_power_mW);
3033 	if (sfp->max_power_mW < 1000) {
3034 		if (sfp->max_power_mW)
3035 			dev_warn(sfp->dev,
3036 				 "Firmware bug: host maximum power should be at least 1W\n");
3037 		sfp->max_power_mW = 1000;
3038 	}
3039 
3040 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
3041 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
3042 
3043 	/* Get the initial state, and always signal TX disable,
3044 	 * since the network interface will not be up.
3045 	 */
3046 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
3047 
3048 	if (sfp->gpio[GPIO_RS0] &&
3049 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RS0]))
3050 		sfp->state |= SFP_F_RS0;
3051 	sfp_set_state(sfp, sfp->state);
3052 	sfp_module_tx_disable(sfp);
3053 	if (sfp->state & SFP_F_PRESENT) {
3054 		rtnl_lock();
3055 		sfp_sm_event(sfp, SFP_E_INSERT);
3056 		rtnl_unlock();
3057 	}
3058 
3059 	for (i = 0; i < GPIO_MAX; i++) {
3060 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
3061 			continue;
3062 
3063 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
3064 		if (sfp->gpio_irq[i] < 0) {
3065 			sfp->gpio_irq[i] = 0;
3066 			sfp->need_poll = true;
3067 			continue;
3068 		}
3069 
3070 		sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
3071 					      "%s-%s", dev_name(sfp->dev),
3072 					      gpio_names[i]);
3073 
3074 		if (!sfp_irq_name)
3075 			return -ENOMEM;
3076 
3077 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
3078 						NULL, sfp_irq,
3079 						IRQF_ONESHOT |
3080 						IRQF_TRIGGER_RISING |
3081 						IRQF_TRIGGER_FALLING,
3082 						sfp_irq_name, sfp);
3083 		if (err) {
3084 			sfp->gpio_irq[i] = 0;
3085 			sfp->need_poll = true;
3086 		}
3087 	}
3088 
3089 	if (sfp->need_poll)
3090 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
3091 
3092 	/* We could have an issue in cases no Tx disable pin is available or
3093 	 * wired as modules using a laser as their light source will continue to
3094 	 * be active when the fiber is removed. This could be a safety issue and
3095 	 * we should at least warn the user about that.
3096 	 */
3097 	if (!sfp->gpio[GPIO_TX_DISABLE])
3098 		dev_warn(sfp->dev,
3099 			 "No tx_disable pin: SFP modules will always be emitting.\n");
3100 
3101 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
3102 	if (!sfp->sfp_bus)
3103 		return -ENOMEM;
3104 
3105 	sfp_debugfs_init(sfp);
3106 
3107 	return 0;
3108 }
3109 
3110 static void sfp_remove(struct platform_device *pdev)
3111 {
3112 	struct sfp *sfp = platform_get_drvdata(pdev);
3113 
3114 	sfp_debugfs_exit(sfp);
3115 	sfp_unregister_socket(sfp->sfp_bus);
3116 
3117 	rtnl_lock();
3118 	sfp_sm_event(sfp, SFP_E_REMOVE);
3119 	rtnl_unlock();
3120 }
3121 
3122 static void sfp_shutdown(struct platform_device *pdev)
3123 {
3124 	struct sfp *sfp = platform_get_drvdata(pdev);
3125 	int i;
3126 
3127 	for (i = 0; i < GPIO_MAX; i++) {
3128 		if (!sfp->gpio_irq[i])
3129 			continue;
3130 
3131 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
3132 	}
3133 
3134 	cancel_delayed_work_sync(&sfp->poll);
3135 	cancel_delayed_work_sync(&sfp->timeout);
3136 }
3137 
3138 static struct platform_driver sfp_driver = {
3139 	.probe = sfp_probe,
3140 	.remove_new = sfp_remove,
3141 	.shutdown = sfp_shutdown,
3142 	.driver = {
3143 		.name = "sfp",
3144 		.of_match_table = sfp_of_match,
3145 	},
3146 };
3147 
3148 static int sfp_init(void)
3149 {
3150 	poll_jiffies = msecs_to_jiffies(100);
3151 
3152 	return platform_driver_register(&sfp_driver);
3153 }
3154 module_init(sfp_init);
3155 
3156 static void sfp_exit(void)
3157 {
3158 	platform_driver_unregister(&sfp_driver);
3159 }
3160 module_exit(sfp_exit);
3161 
3162 MODULE_ALIAS("platform:sfp");
3163 MODULE_AUTHOR("Russell King");
3164 MODULE_LICENSE("GPL v2");
3165 MODULE_DESCRIPTION("SFP cage support");
3166