xref: /linux/drivers/net/phy/sfp.c (revision 1553a1c48281243359a9529a10ddb551f3b967ab)
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-10", sfp_fixup_rollball),
510 	SFP_QUIRK_F("Turris", "RTSFP-10G", sfp_fixup_rollball),
511 };
512 
513 static size_t sfp_strlen(const char *str, size_t maxlen)
514 {
515 	size_t size, i;
516 
517 	/* Trailing characters should be filled with space chars, but
518 	 * some manufacturers can't read SFF-8472 and use NUL.
519 	 */
520 	for (i = 0, size = 0; i < maxlen; i++)
521 		if (str[i] != ' ' && str[i] != '\0')
522 			size = i + 1;
523 
524 	return size;
525 }
526 
527 static bool sfp_match(const char *qs, const char *str, size_t len)
528 {
529 	if (!qs)
530 		return true;
531 	if (strlen(qs) != len)
532 		return false;
533 	return !strncmp(qs, str, len);
534 }
535 
536 static const struct sfp_quirk *sfp_lookup_quirk(const struct sfp_eeprom_id *id)
537 {
538 	const struct sfp_quirk *q;
539 	unsigned int i;
540 	size_t vs, ps;
541 
542 	vs = sfp_strlen(id->base.vendor_name, ARRAY_SIZE(id->base.vendor_name));
543 	ps = sfp_strlen(id->base.vendor_pn, ARRAY_SIZE(id->base.vendor_pn));
544 
545 	for (i = 0, q = sfp_quirks; i < ARRAY_SIZE(sfp_quirks); i++, q++)
546 		if (sfp_match(q->vendor, id->base.vendor_name, vs) &&
547 		    sfp_match(q->part, id->base.vendor_pn, ps))
548 			return q;
549 
550 	return NULL;
551 }
552 
553 static unsigned long poll_jiffies;
554 
555 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
556 {
557 	unsigned int i, state, v;
558 
559 	for (i = state = 0; i < GPIO_MAX; i++) {
560 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
561 			continue;
562 
563 		v = gpiod_get_value_cansleep(sfp->gpio[i]);
564 		if (v)
565 			state |= BIT(i);
566 	}
567 
568 	return state;
569 }
570 
571 static unsigned int sff_gpio_get_state(struct sfp *sfp)
572 {
573 	return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
574 }
575 
576 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
577 {
578 	unsigned int drive;
579 
580 	if (state & SFP_F_PRESENT)
581 		/* If the module is present, drive the requested signals */
582 		drive = sfp->state_hw_drive;
583 	else
584 		/* Otherwise, let them float to the pull-ups */
585 		drive = 0;
586 
587 	if (sfp->gpio[GPIO_TX_DISABLE]) {
588 		if (drive & SFP_F_TX_DISABLE)
589 			gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
590 					       state & SFP_F_TX_DISABLE);
591 		else
592 			gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
593 	}
594 
595 	if (sfp->gpio[GPIO_RS0]) {
596 		if (drive & SFP_F_RS0)
597 			gpiod_direction_output(sfp->gpio[GPIO_RS0],
598 					       state & SFP_F_RS0);
599 		else
600 			gpiod_direction_input(sfp->gpio[GPIO_RS0]);
601 	}
602 
603 	if (sfp->gpio[GPIO_RS1]) {
604 		if (drive & SFP_F_RS1)
605 			gpiod_direction_output(sfp->gpio[GPIO_RS1],
606 					       state & SFP_F_RS1);
607 		else
608 			gpiod_direction_input(sfp->gpio[GPIO_RS1]);
609 	}
610 }
611 
612 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
613 			size_t len)
614 {
615 	struct i2c_msg msgs[2];
616 	u8 bus_addr = a2 ? 0x51 : 0x50;
617 	size_t block_size = sfp->i2c_block_size;
618 	size_t this_len;
619 	int ret;
620 
621 	msgs[0].addr = bus_addr;
622 	msgs[0].flags = 0;
623 	msgs[0].len = 1;
624 	msgs[0].buf = &dev_addr;
625 	msgs[1].addr = bus_addr;
626 	msgs[1].flags = I2C_M_RD;
627 	msgs[1].len = len;
628 	msgs[1].buf = buf;
629 
630 	while (len) {
631 		this_len = len;
632 		if (this_len > block_size)
633 			this_len = block_size;
634 
635 		msgs[1].len = this_len;
636 
637 		ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
638 		if (ret < 0)
639 			return ret;
640 
641 		if (ret != ARRAY_SIZE(msgs))
642 			break;
643 
644 		msgs[1].buf += this_len;
645 		dev_addr += this_len;
646 		len -= this_len;
647 	}
648 
649 	return msgs[1].buf - (u8 *)buf;
650 }
651 
652 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
653 	size_t len)
654 {
655 	struct i2c_msg msgs[1];
656 	u8 bus_addr = a2 ? 0x51 : 0x50;
657 	int ret;
658 
659 	msgs[0].addr = bus_addr;
660 	msgs[0].flags = 0;
661 	msgs[0].len = 1 + len;
662 	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
663 	if (!msgs[0].buf)
664 		return -ENOMEM;
665 
666 	msgs[0].buf[0] = dev_addr;
667 	memcpy(&msgs[0].buf[1], buf, len);
668 
669 	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
670 
671 	kfree(msgs[0].buf);
672 
673 	if (ret < 0)
674 		return ret;
675 
676 	return ret == ARRAY_SIZE(msgs) ? len : 0;
677 }
678 
679 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
680 {
681 	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
682 		return -EINVAL;
683 
684 	sfp->i2c = i2c;
685 	sfp->read = sfp_i2c_read;
686 	sfp->write = sfp_i2c_write;
687 
688 	return 0;
689 }
690 
691 static int sfp_i2c_mdiobus_create(struct sfp *sfp)
692 {
693 	struct mii_bus *i2c_mii;
694 	int ret;
695 
696 	i2c_mii = mdio_i2c_alloc(sfp->dev, sfp->i2c, sfp->mdio_protocol);
697 	if (IS_ERR(i2c_mii))
698 		return PTR_ERR(i2c_mii);
699 
700 	i2c_mii->name = "SFP I2C Bus";
701 	i2c_mii->phy_mask = ~0;
702 
703 	ret = mdiobus_register(i2c_mii);
704 	if (ret < 0) {
705 		mdiobus_free(i2c_mii);
706 		return ret;
707 	}
708 
709 	sfp->i2c_mii = i2c_mii;
710 
711 	return 0;
712 }
713 
714 static void sfp_i2c_mdiobus_destroy(struct sfp *sfp)
715 {
716 	mdiobus_unregister(sfp->i2c_mii);
717 	sfp->i2c_mii = NULL;
718 }
719 
720 /* Interface */
721 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
722 {
723 	return sfp->read(sfp, a2, addr, buf, len);
724 }
725 
726 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
727 {
728 	return sfp->write(sfp, a2, addr, buf, len);
729 }
730 
731 static int sfp_modify_u8(struct sfp *sfp, bool a2, u8 addr, u8 mask, u8 val)
732 {
733 	int ret;
734 	u8 old, v;
735 
736 	ret = sfp_read(sfp, a2, addr, &old, sizeof(old));
737 	if (ret != sizeof(old))
738 		return ret;
739 
740 	v = (old & ~mask) | (val & mask);
741 	if (v == old)
742 		return sizeof(v);
743 
744 	return sfp_write(sfp, a2, addr, &v, sizeof(v));
745 }
746 
747 static unsigned int sfp_soft_get_state(struct sfp *sfp)
748 {
749 	unsigned int state = 0;
750 	u8 status;
751 	int ret;
752 
753 	ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
754 	if (ret == sizeof(status)) {
755 		if (status & SFP_STATUS_RX_LOS)
756 			state |= SFP_F_LOS;
757 		if (status & SFP_STATUS_TX_FAULT)
758 			state |= SFP_F_TX_FAULT;
759 	} else {
760 		dev_err_ratelimited(sfp->dev,
761 				    "failed to read SFP soft status: %pe\n",
762 				    ERR_PTR(ret));
763 		/* Preserve the current state */
764 		state = sfp->state;
765 	}
766 
767 	return state & sfp->state_soft_mask;
768 }
769 
770 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state,
771 			       unsigned int soft)
772 {
773 	u8 mask = 0;
774 	u8 val = 0;
775 
776 	if (soft & SFP_F_TX_DISABLE)
777 		mask |= SFP_STATUS_TX_DISABLE_FORCE;
778 	if (state & SFP_F_TX_DISABLE)
779 		val |= SFP_STATUS_TX_DISABLE_FORCE;
780 
781 	if (soft & SFP_F_RS0)
782 		mask |= SFP_STATUS_RS0_SELECT;
783 	if (state & SFP_F_RS0)
784 		val |= SFP_STATUS_RS0_SELECT;
785 
786 	if (mask)
787 		sfp_modify_u8(sfp, true, SFP_STATUS, mask, val);
788 
789 	val = mask = 0;
790 	if (soft & SFP_F_RS1)
791 		mask |= SFP_EXT_STATUS_RS1_SELECT;
792 	if (state & SFP_F_RS1)
793 		val |= SFP_EXT_STATUS_RS1_SELECT;
794 
795 	if (mask)
796 		sfp_modify_u8(sfp, true, SFP_EXT_STATUS, mask, val);
797 }
798 
799 static void sfp_soft_start_poll(struct sfp *sfp)
800 {
801 	const struct sfp_eeprom_id *id = &sfp->id;
802 	unsigned int mask = 0;
803 
804 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE)
805 		mask |= SFP_F_TX_DISABLE;
806 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT)
807 		mask |= SFP_F_TX_FAULT;
808 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS)
809 		mask |= SFP_F_LOS;
810 	if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RATE_SELECT)
811 		mask |= sfp->rs_state_mask;
812 
813 	mutex_lock(&sfp->st_mutex);
814 	// Poll the soft state for hardware pins we want to ignore
815 	sfp->state_soft_mask = ~sfp->state_hw_mask & ~sfp->state_ignore_mask &
816 			       mask;
817 
818 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
819 	    !sfp->need_poll)
820 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
821 	mutex_unlock(&sfp->st_mutex);
822 }
823 
824 static void sfp_soft_stop_poll(struct sfp *sfp)
825 {
826 	mutex_lock(&sfp->st_mutex);
827 	sfp->state_soft_mask = 0;
828 	mutex_unlock(&sfp->st_mutex);
829 }
830 
831 /* sfp_get_state() - must be called with st_mutex held, or in the
832  * initialisation path.
833  */
834 static unsigned int sfp_get_state(struct sfp *sfp)
835 {
836 	unsigned int soft = sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT);
837 	unsigned int state;
838 
839 	state = sfp->get_state(sfp) & sfp->state_hw_mask;
840 	if (state & SFP_F_PRESENT && soft)
841 		state |= sfp_soft_get_state(sfp);
842 
843 	return state;
844 }
845 
846 /* sfp_set_state() - must be called with st_mutex held, or in the
847  * initialisation path.
848  */
849 static void sfp_set_state(struct sfp *sfp, unsigned int state)
850 {
851 	unsigned int soft;
852 
853 	sfp->set_state(sfp, state);
854 
855 	soft = sfp->state_soft_mask & SFP_F_OUTPUTS;
856 	if (state & SFP_F_PRESENT && soft)
857 		sfp_soft_set_state(sfp, state, soft);
858 }
859 
860 static void sfp_mod_state(struct sfp *sfp, unsigned int mask, unsigned int set)
861 {
862 	mutex_lock(&sfp->st_mutex);
863 	sfp->state = (sfp->state & ~mask) | set;
864 	sfp_set_state(sfp, sfp->state);
865 	mutex_unlock(&sfp->st_mutex);
866 }
867 
868 static unsigned int sfp_check(void *buf, size_t len)
869 {
870 	u8 *p, check;
871 
872 	for (p = buf, check = 0; len; p++, len--)
873 		check += *p;
874 
875 	return check;
876 }
877 
878 /* hwmon */
879 #if IS_ENABLED(CONFIG_HWMON)
880 static umode_t sfp_hwmon_is_visible(const void *data,
881 				    enum hwmon_sensor_types type,
882 				    u32 attr, int channel)
883 {
884 	const struct sfp *sfp = data;
885 
886 	switch (type) {
887 	case hwmon_temp:
888 		switch (attr) {
889 		case hwmon_temp_min_alarm:
890 		case hwmon_temp_max_alarm:
891 		case hwmon_temp_lcrit_alarm:
892 		case hwmon_temp_crit_alarm:
893 		case hwmon_temp_min:
894 		case hwmon_temp_max:
895 		case hwmon_temp_lcrit:
896 		case hwmon_temp_crit:
897 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
898 				return 0;
899 			fallthrough;
900 		case hwmon_temp_input:
901 		case hwmon_temp_label:
902 			return 0444;
903 		default:
904 			return 0;
905 		}
906 	case hwmon_in:
907 		switch (attr) {
908 		case hwmon_in_min_alarm:
909 		case hwmon_in_max_alarm:
910 		case hwmon_in_lcrit_alarm:
911 		case hwmon_in_crit_alarm:
912 		case hwmon_in_min:
913 		case hwmon_in_max:
914 		case hwmon_in_lcrit:
915 		case hwmon_in_crit:
916 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
917 				return 0;
918 			fallthrough;
919 		case hwmon_in_input:
920 		case hwmon_in_label:
921 			return 0444;
922 		default:
923 			return 0;
924 		}
925 	case hwmon_curr:
926 		switch (attr) {
927 		case hwmon_curr_min_alarm:
928 		case hwmon_curr_max_alarm:
929 		case hwmon_curr_lcrit_alarm:
930 		case hwmon_curr_crit_alarm:
931 		case hwmon_curr_min:
932 		case hwmon_curr_max:
933 		case hwmon_curr_lcrit:
934 		case hwmon_curr_crit:
935 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
936 				return 0;
937 			fallthrough;
938 		case hwmon_curr_input:
939 		case hwmon_curr_label:
940 			return 0444;
941 		default:
942 			return 0;
943 		}
944 	case hwmon_power:
945 		/* External calibration of receive power requires
946 		 * floating point arithmetic. Doing that in the kernel
947 		 * is not easy, so just skip it. If the module does
948 		 * not require external calibration, we can however
949 		 * show receiver power, since FP is then not needed.
950 		 */
951 		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
952 		    channel == 1)
953 			return 0;
954 		switch (attr) {
955 		case hwmon_power_min_alarm:
956 		case hwmon_power_max_alarm:
957 		case hwmon_power_lcrit_alarm:
958 		case hwmon_power_crit_alarm:
959 		case hwmon_power_min:
960 		case hwmon_power_max:
961 		case hwmon_power_lcrit:
962 		case hwmon_power_crit:
963 			if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
964 				return 0;
965 			fallthrough;
966 		case hwmon_power_input:
967 		case hwmon_power_label:
968 			return 0444;
969 		default:
970 			return 0;
971 		}
972 	default:
973 		return 0;
974 	}
975 }
976 
977 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
978 {
979 	__be16 val;
980 	int err;
981 
982 	err = sfp_read(sfp, true, reg, &val, sizeof(val));
983 	if (err < 0)
984 		return err;
985 
986 	*value = be16_to_cpu(val);
987 
988 	return 0;
989 }
990 
991 static void sfp_hwmon_to_rx_power(long *value)
992 {
993 	*value = DIV_ROUND_CLOSEST(*value, 10);
994 }
995 
996 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
997 				long *value)
998 {
999 	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
1000 		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
1001 }
1002 
1003 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
1004 {
1005 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
1006 			    be16_to_cpu(sfp->diag.cal_t_offset), value);
1007 
1008 	if (*value >= 0x8000)
1009 		*value -= 0x10000;
1010 
1011 	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
1012 }
1013 
1014 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
1015 {
1016 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
1017 			    be16_to_cpu(sfp->diag.cal_v_offset), value);
1018 
1019 	*value = DIV_ROUND_CLOSEST(*value, 10);
1020 }
1021 
1022 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
1023 {
1024 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
1025 			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
1026 
1027 	*value = DIV_ROUND_CLOSEST(*value, 500);
1028 }
1029 
1030 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
1031 {
1032 	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
1033 			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
1034 
1035 	*value = DIV_ROUND_CLOSEST(*value, 10);
1036 }
1037 
1038 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
1039 {
1040 	int err;
1041 
1042 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1043 	if (err < 0)
1044 		return err;
1045 
1046 	sfp_hwmon_calibrate_temp(sfp, value);
1047 
1048 	return 0;
1049 }
1050 
1051 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
1052 {
1053 	int err;
1054 
1055 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1056 	if (err < 0)
1057 		return err;
1058 
1059 	sfp_hwmon_calibrate_vcc(sfp, value);
1060 
1061 	return 0;
1062 }
1063 
1064 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
1065 {
1066 	int err;
1067 
1068 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1069 	if (err < 0)
1070 		return err;
1071 
1072 	sfp_hwmon_calibrate_bias(sfp, value);
1073 
1074 	return 0;
1075 }
1076 
1077 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
1078 {
1079 	int err;
1080 
1081 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1082 	if (err < 0)
1083 		return err;
1084 
1085 	sfp_hwmon_calibrate_tx_power(sfp, value);
1086 
1087 	return 0;
1088 }
1089 
1090 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
1091 {
1092 	int err;
1093 
1094 	err = sfp_hwmon_read_sensor(sfp, reg, value);
1095 	if (err < 0)
1096 		return err;
1097 
1098 	sfp_hwmon_to_rx_power(value);
1099 
1100 	return 0;
1101 }
1102 
1103 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
1104 {
1105 	u8 status;
1106 	int err;
1107 
1108 	switch (attr) {
1109 	case hwmon_temp_input:
1110 		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
1111 
1112 	case hwmon_temp_lcrit:
1113 		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
1114 		sfp_hwmon_calibrate_temp(sfp, value);
1115 		return 0;
1116 
1117 	case hwmon_temp_min:
1118 		*value = be16_to_cpu(sfp->diag.temp_low_warn);
1119 		sfp_hwmon_calibrate_temp(sfp, value);
1120 		return 0;
1121 	case hwmon_temp_max:
1122 		*value = be16_to_cpu(sfp->diag.temp_high_warn);
1123 		sfp_hwmon_calibrate_temp(sfp, value);
1124 		return 0;
1125 
1126 	case hwmon_temp_crit:
1127 		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
1128 		sfp_hwmon_calibrate_temp(sfp, value);
1129 		return 0;
1130 
1131 	case hwmon_temp_lcrit_alarm:
1132 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1133 		if (err < 0)
1134 			return err;
1135 
1136 		*value = !!(status & SFP_ALARM0_TEMP_LOW);
1137 		return 0;
1138 
1139 	case hwmon_temp_min_alarm:
1140 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1141 		if (err < 0)
1142 			return err;
1143 
1144 		*value = !!(status & SFP_WARN0_TEMP_LOW);
1145 		return 0;
1146 
1147 	case hwmon_temp_max_alarm:
1148 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1149 		if (err < 0)
1150 			return err;
1151 
1152 		*value = !!(status & SFP_WARN0_TEMP_HIGH);
1153 		return 0;
1154 
1155 	case hwmon_temp_crit_alarm:
1156 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1157 		if (err < 0)
1158 			return err;
1159 
1160 		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
1161 		return 0;
1162 	default:
1163 		return -EOPNOTSUPP;
1164 	}
1165 
1166 	return -EOPNOTSUPP;
1167 }
1168 
1169 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
1170 {
1171 	u8 status;
1172 	int err;
1173 
1174 	switch (attr) {
1175 	case hwmon_in_input:
1176 		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
1177 
1178 	case hwmon_in_lcrit:
1179 		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
1180 		sfp_hwmon_calibrate_vcc(sfp, value);
1181 		return 0;
1182 
1183 	case hwmon_in_min:
1184 		*value = be16_to_cpu(sfp->diag.volt_low_warn);
1185 		sfp_hwmon_calibrate_vcc(sfp, value);
1186 		return 0;
1187 
1188 	case hwmon_in_max:
1189 		*value = be16_to_cpu(sfp->diag.volt_high_warn);
1190 		sfp_hwmon_calibrate_vcc(sfp, value);
1191 		return 0;
1192 
1193 	case hwmon_in_crit:
1194 		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
1195 		sfp_hwmon_calibrate_vcc(sfp, value);
1196 		return 0;
1197 
1198 	case hwmon_in_lcrit_alarm:
1199 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1200 		if (err < 0)
1201 			return err;
1202 
1203 		*value = !!(status & SFP_ALARM0_VCC_LOW);
1204 		return 0;
1205 
1206 	case hwmon_in_min_alarm:
1207 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1208 		if (err < 0)
1209 			return err;
1210 
1211 		*value = !!(status & SFP_WARN0_VCC_LOW);
1212 		return 0;
1213 
1214 	case hwmon_in_max_alarm:
1215 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1216 		if (err < 0)
1217 			return err;
1218 
1219 		*value = !!(status & SFP_WARN0_VCC_HIGH);
1220 		return 0;
1221 
1222 	case hwmon_in_crit_alarm:
1223 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1224 		if (err < 0)
1225 			return err;
1226 
1227 		*value = !!(status & SFP_ALARM0_VCC_HIGH);
1228 		return 0;
1229 	default:
1230 		return -EOPNOTSUPP;
1231 	}
1232 
1233 	return -EOPNOTSUPP;
1234 }
1235 
1236 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
1237 {
1238 	u8 status;
1239 	int err;
1240 
1241 	switch (attr) {
1242 	case hwmon_curr_input:
1243 		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
1244 
1245 	case hwmon_curr_lcrit:
1246 		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
1247 		sfp_hwmon_calibrate_bias(sfp, value);
1248 		return 0;
1249 
1250 	case hwmon_curr_min:
1251 		*value = be16_to_cpu(sfp->diag.bias_low_warn);
1252 		sfp_hwmon_calibrate_bias(sfp, value);
1253 		return 0;
1254 
1255 	case hwmon_curr_max:
1256 		*value = be16_to_cpu(sfp->diag.bias_high_warn);
1257 		sfp_hwmon_calibrate_bias(sfp, value);
1258 		return 0;
1259 
1260 	case hwmon_curr_crit:
1261 		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
1262 		sfp_hwmon_calibrate_bias(sfp, value);
1263 		return 0;
1264 
1265 	case hwmon_curr_lcrit_alarm:
1266 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1267 		if (err < 0)
1268 			return err;
1269 
1270 		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
1271 		return 0;
1272 
1273 	case hwmon_curr_min_alarm:
1274 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1275 		if (err < 0)
1276 			return err;
1277 
1278 		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
1279 		return 0;
1280 
1281 	case hwmon_curr_max_alarm:
1282 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1283 		if (err < 0)
1284 			return err;
1285 
1286 		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
1287 		return 0;
1288 
1289 	case hwmon_curr_crit_alarm:
1290 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1291 		if (err < 0)
1292 			return err;
1293 
1294 		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
1295 		return 0;
1296 	default:
1297 		return -EOPNOTSUPP;
1298 	}
1299 
1300 	return -EOPNOTSUPP;
1301 }
1302 
1303 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
1304 {
1305 	u8 status;
1306 	int err;
1307 
1308 	switch (attr) {
1309 	case hwmon_power_input:
1310 		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
1311 
1312 	case hwmon_power_lcrit:
1313 		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
1314 		sfp_hwmon_calibrate_tx_power(sfp, value);
1315 		return 0;
1316 
1317 	case hwmon_power_min:
1318 		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
1319 		sfp_hwmon_calibrate_tx_power(sfp, value);
1320 		return 0;
1321 
1322 	case hwmon_power_max:
1323 		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
1324 		sfp_hwmon_calibrate_tx_power(sfp, value);
1325 		return 0;
1326 
1327 	case hwmon_power_crit:
1328 		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
1329 		sfp_hwmon_calibrate_tx_power(sfp, value);
1330 		return 0;
1331 
1332 	case hwmon_power_lcrit_alarm:
1333 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1334 		if (err < 0)
1335 			return err;
1336 
1337 		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
1338 		return 0;
1339 
1340 	case hwmon_power_min_alarm:
1341 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1342 		if (err < 0)
1343 			return err;
1344 
1345 		*value = !!(status & SFP_WARN0_TXPWR_LOW);
1346 		return 0;
1347 
1348 	case hwmon_power_max_alarm:
1349 		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
1350 		if (err < 0)
1351 			return err;
1352 
1353 		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
1354 		return 0;
1355 
1356 	case hwmon_power_crit_alarm:
1357 		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
1358 		if (err < 0)
1359 			return err;
1360 
1361 		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
1362 		return 0;
1363 	default:
1364 		return -EOPNOTSUPP;
1365 	}
1366 
1367 	return -EOPNOTSUPP;
1368 }
1369 
1370 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
1371 {
1372 	u8 status;
1373 	int err;
1374 
1375 	switch (attr) {
1376 	case hwmon_power_input:
1377 		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
1378 
1379 	case hwmon_power_lcrit:
1380 		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
1381 		sfp_hwmon_to_rx_power(value);
1382 		return 0;
1383 
1384 	case hwmon_power_min:
1385 		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
1386 		sfp_hwmon_to_rx_power(value);
1387 		return 0;
1388 
1389 	case hwmon_power_max:
1390 		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
1391 		sfp_hwmon_to_rx_power(value);
1392 		return 0;
1393 
1394 	case hwmon_power_crit:
1395 		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
1396 		sfp_hwmon_to_rx_power(value);
1397 		return 0;
1398 
1399 	case hwmon_power_lcrit_alarm:
1400 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1401 		if (err < 0)
1402 			return err;
1403 
1404 		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
1405 		return 0;
1406 
1407 	case hwmon_power_min_alarm:
1408 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1409 		if (err < 0)
1410 			return err;
1411 
1412 		*value = !!(status & SFP_WARN1_RXPWR_LOW);
1413 		return 0;
1414 
1415 	case hwmon_power_max_alarm:
1416 		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
1417 		if (err < 0)
1418 			return err;
1419 
1420 		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
1421 		return 0;
1422 
1423 	case hwmon_power_crit_alarm:
1424 		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
1425 		if (err < 0)
1426 			return err;
1427 
1428 		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
1429 		return 0;
1430 	default:
1431 		return -EOPNOTSUPP;
1432 	}
1433 
1434 	return -EOPNOTSUPP;
1435 }
1436 
1437 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
1438 			  u32 attr, int channel, long *value)
1439 {
1440 	struct sfp *sfp = dev_get_drvdata(dev);
1441 
1442 	switch (type) {
1443 	case hwmon_temp:
1444 		return sfp_hwmon_temp(sfp, attr, value);
1445 	case hwmon_in:
1446 		return sfp_hwmon_vcc(sfp, attr, value);
1447 	case hwmon_curr:
1448 		return sfp_hwmon_bias(sfp, attr, value);
1449 	case hwmon_power:
1450 		switch (channel) {
1451 		case 0:
1452 			return sfp_hwmon_tx_power(sfp, attr, value);
1453 		case 1:
1454 			return sfp_hwmon_rx_power(sfp, attr, value);
1455 		default:
1456 			return -EOPNOTSUPP;
1457 		}
1458 	default:
1459 		return -EOPNOTSUPP;
1460 	}
1461 }
1462 
1463 static const char *const sfp_hwmon_power_labels[] = {
1464 	"TX_power",
1465 	"RX_power",
1466 };
1467 
1468 static int sfp_hwmon_read_string(struct device *dev,
1469 				 enum hwmon_sensor_types type,
1470 				 u32 attr, int channel, const char **str)
1471 {
1472 	switch (type) {
1473 	case hwmon_curr:
1474 		switch (attr) {
1475 		case hwmon_curr_label:
1476 			*str = "bias";
1477 			return 0;
1478 		default:
1479 			return -EOPNOTSUPP;
1480 		}
1481 		break;
1482 	case hwmon_temp:
1483 		switch (attr) {
1484 		case hwmon_temp_label:
1485 			*str = "temperature";
1486 			return 0;
1487 		default:
1488 			return -EOPNOTSUPP;
1489 		}
1490 		break;
1491 	case hwmon_in:
1492 		switch (attr) {
1493 		case hwmon_in_label:
1494 			*str = "VCC";
1495 			return 0;
1496 		default:
1497 			return -EOPNOTSUPP;
1498 		}
1499 		break;
1500 	case hwmon_power:
1501 		switch (attr) {
1502 		case hwmon_power_label:
1503 			*str = sfp_hwmon_power_labels[channel];
1504 			return 0;
1505 		default:
1506 			return -EOPNOTSUPP;
1507 		}
1508 		break;
1509 	default:
1510 		return -EOPNOTSUPP;
1511 	}
1512 
1513 	return -EOPNOTSUPP;
1514 }
1515 
1516 static const struct hwmon_ops sfp_hwmon_ops = {
1517 	.is_visible = sfp_hwmon_is_visible,
1518 	.read = sfp_hwmon_read,
1519 	.read_string = sfp_hwmon_read_string,
1520 };
1521 
1522 static const struct hwmon_channel_info * const sfp_hwmon_info[] = {
1523 	HWMON_CHANNEL_INFO(chip,
1524 			   HWMON_C_REGISTER_TZ),
1525 	HWMON_CHANNEL_INFO(in,
1526 			   HWMON_I_INPUT |
1527 			   HWMON_I_MAX | HWMON_I_MIN |
1528 			   HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
1529 			   HWMON_I_CRIT | HWMON_I_LCRIT |
1530 			   HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
1531 			   HWMON_I_LABEL),
1532 	HWMON_CHANNEL_INFO(temp,
1533 			   HWMON_T_INPUT |
1534 			   HWMON_T_MAX | HWMON_T_MIN |
1535 			   HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
1536 			   HWMON_T_CRIT | HWMON_T_LCRIT |
1537 			   HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
1538 			   HWMON_T_LABEL),
1539 	HWMON_CHANNEL_INFO(curr,
1540 			   HWMON_C_INPUT |
1541 			   HWMON_C_MAX | HWMON_C_MIN |
1542 			   HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
1543 			   HWMON_C_CRIT | HWMON_C_LCRIT |
1544 			   HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
1545 			   HWMON_C_LABEL),
1546 	HWMON_CHANNEL_INFO(power,
1547 			   /* Transmit power */
1548 			   HWMON_P_INPUT |
1549 			   HWMON_P_MAX | HWMON_P_MIN |
1550 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1551 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1552 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1553 			   HWMON_P_LABEL,
1554 			   /* Receive power */
1555 			   HWMON_P_INPUT |
1556 			   HWMON_P_MAX | HWMON_P_MIN |
1557 			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1558 			   HWMON_P_CRIT | HWMON_P_LCRIT |
1559 			   HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
1560 			   HWMON_P_LABEL),
1561 	NULL,
1562 };
1563 
1564 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
1565 	.ops = &sfp_hwmon_ops,
1566 	.info = sfp_hwmon_info,
1567 };
1568 
1569 static void sfp_hwmon_probe(struct work_struct *work)
1570 {
1571 	struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
1572 	int err;
1573 
1574 	/* hwmon interface needs to access 16bit registers in atomic way to
1575 	 * guarantee coherency of the diagnostic monitoring data. If it is not
1576 	 * possible to guarantee coherency because EEPROM is broken in such way
1577 	 * that does not support atomic 16bit read operation then we have to
1578 	 * skip registration of hwmon device.
1579 	 */
1580 	if (sfp->i2c_block_size < 2) {
1581 		dev_info(sfp->dev,
1582 			 "skipping hwmon device registration due to broken EEPROM\n");
1583 		dev_info(sfp->dev,
1584 			 "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
1585 		return;
1586 	}
1587 
1588 	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
1589 	if (err < 0) {
1590 		if (sfp->hwmon_tries--) {
1591 			mod_delayed_work(system_wq, &sfp->hwmon_probe,
1592 					 T_PROBE_RETRY_SLOW);
1593 		} else {
1594 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
1595 				 ERR_PTR(err));
1596 		}
1597 		return;
1598 	}
1599 
1600 	sfp->hwmon_name = hwmon_sanitize_name(dev_name(sfp->dev));
1601 	if (IS_ERR(sfp->hwmon_name)) {
1602 		dev_err(sfp->dev, "out of memory for hwmon name\n");
1603 		return;
1604 	}
1605 
1606 	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
1607 							 sfp->hwmon_name, sfp,
1608 							 &sfp_hwmon_chip_info,
1609 							 NULL);
1610 	if (IS_ERR(sfp->hwmon_dev))
1611 		dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
1612 			PTR_ERR(sfp->hwmon_dev));
1613 }
1614 
1615 static int sfp_hwmon_insert(struct sfp *sfp)
1616 {
1617 	if (sfp->have_a2 && sfp->id.ext.diagmon & SFP_DIAGMON_DDM) {
1618 		mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
1619 		sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
1620 	}
1621 
1622 	return 0;
1623 }
1624 
1625 static void sfp_hwmon_remove(struct sfp *sfp)
1626 {
1627 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1628 	if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
1629 		hwmon_device_unregister(sfp->hwmon_dev);
1630 		sfp->hwmon_dev = NULL;
1631 		kfree(sfp->hwmon_name);
1632 	}
1633 }
1634 
1635 static int sfp_hwmon_init(struct sfp *sfp)
1636 {
1637 	INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
1638 
1639 	return 0;
1640 }
1641 
1642 static void sfp_hwmon_exit(struct sfp *sfp)
1643 {
1644 	cancel_delayed_work_sync(&sfp->hwmon_probe);
1645 }
1646 #else
1647 static int sfp_hwmon_insert(struct sfp *sfp)
1648 {
1649 	return 0;
1650 }
1651 
1652 static void sfp_hwmon_remove(struct sfp *sfp)
1653 {
1654 }
1655 
1656 static int sfp_hwmon_init(struct sfp *sfp)
1657 {
1658 	return 0;
1659 }
1660 
1661 static void sfp_hwmon_exit(struct sfp *sfp)
1662 {
1663 }
1664 #endif
1665 
1666 /* Helpers */
1667 static void sfp_module_tx_disable(struct sfp *sfp)
1668 {
1669 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1670 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
1671 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, SFP_F_TX_DISABLE);
1672 }
1673 
1674 static void sfp_module_tx_enable(struct sfp *sfp)
1675 {
1676 	dev_dbg(sfp->dev, "tx disable %u -> %u\n",
1677 		sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
1678 	sfp_mod_state(sfp, SFP_F_TX_DISABLE, 0);
1679 }
1680 
1681 #if IS_ENABLED(CONFIG_DEBUG_FS)
1682 static int sfp_debug_state_show(struct seq_file *s, void *data)
1683 {
1684 	struct sfp *sfp = s->private;
1685 
1686 	seq_printf(s, "Module state: %s\n",
1687 		   mod_state_to_str(sfp->sm_mod_state));
1688 	seq_printf(s, "Module probe attempts: %d %d\n",
1689 		   R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
1690 		   R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
1691 	seq_printf(s, "Device state: %s\n",
1692 		   dev_state_to_str(sfp->sm_dev_state));
1693 	seq_printf(s, "Main state: %s\n",
1694 		   sm_state_to_str(sfp->sm_state));
1695 	seq_printf(s, "Fault recovery remaining retries: %d\n",
1696 		   sfp->sm_fault_retries);
1697 	seq_printf(s, "PHY probe remaining retries: %d\n",
1698 		   sfp->sm_phy_retries);
1699 	seq_printf(s, "Signalling rate: %u kBd\n", sfp->rate_kbd);
1700 	seq_printf(s, "Rate select threshold: %u kBd\n",
1701 		   sfp->rs_threshold_kbd);
1702 	seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
1703 	seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
1704 	seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
1705 	seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
1706 	seq_printf(s, "rs0: %d\n", !!(sfp->state & SFP_F_RS0));
1707 	seq_printf(s, "rs1: %d\n", !!(sfp->state & SFP_F_RS1));
1708 	return 0;
1709 }
1710 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
1711 
1712 static void sfp_debugfs_init(struct sfp *sfp)
1713 {
1714 	sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
1715 
1716 	debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
1717 			    &sfp_debug_state_fops);
1718 }
1719 
1720 static void sfp_debugfs_exit(struct sfp *sfp)
1721 {
1722 	debugfs_remove_recursive(sfp->debugfs_dir);
1723 }
1724 #else
1725 static void sfp_debugfs_init(struct sfp *sfp)
1726 {
1727 }
1728 
1729 static void sfp_debugfs_exit(struct sfp *sfp)
1730 {
1731 }
1732 #endif
1733 
1734 static void sfp_module_tx_fault_reset(struct sfp *sfp)
1735 {
1736 	unsigned int state;
1737 
1738 	mutex_lock(&sfp->st_mutex);
1739 	state = sfp->state;
1740 	if (!(state & SFP_F_TX_DISABLE)) {
1741 		sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
1742 
1743 		udelay(T_RESET_US);
1744 
1745 		sfp_set_state(sfp, state);
1746 	}
1747 	mutex_unlock(&sfp->st_mutex);
1748 }
1749 
1750 /* SFP state machine */
1751 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
1752 {
1753 	if (timeout)
1754 		mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
1755 				 timeout);
1756 	else
1757 		cancel_delayed_work(&sfp->timeout);
1758 }
1759 
1760 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
1761 			unsigned int timeout)
1762 {
1763 	sfp->sm_state = state;
1764 	sfp_sm_set_timer(sfp, timeout);
1765 }
1766 
1767 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
1768 			    unsigned int timeout)
1769 {
1770 	sfp->sm_mod_state = state;
1771 	sfp_sm_set_timer(sfp, timeout);
1772 }
1773 
1774 static void sfp_sm_phy_detach(struct sfp *sfp)
1775 {
1776 	sfp_remove_phy(sfp->sfp_bus);
1777 	phy_device_remove(sfp->mod_phy);
1778 	phy_device_free(sfp->mod_phy);
1779 	sfp->mod_phy = NULL;
1780 }
1781 
1782 static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
1783 {
1784 	struct phy_device *phy;
1785 	int err;
1786 
1787 	phy = get_phy_device(sfp->i2c_mii, addr, is_c45);
1788 	if (phy == ERR_PTR(-ENODEV))
1789 		return PTR_ERR(phy);
1790 	if (IS_ERR(phy)) {
1791 		dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
1792 		return PTR_ERR(phy);
1793 	}
1794 
1795 	/* Mark this PHY as being on a SFP module */
1796 	phy->is_on_sfp_module = true;
1797 
1798 	err = phy_device_register(phy);
1799 	if (err) {
1800 		phy_device_free(phy);
1801 		dev_err(sfp->dev, "phy_device_register failed: %pe\n",
1802 			ERR_PTR(err));
1803 		return err;
1804 	}
1805 
1806 	err = sfp_add_phy(sfp->sfp_bus, phy);
1807 	if (err) {
1808 		phy_device_remove(phy);
1809 		phy_device_free(phy);
1810 		dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
1811 		return err;
1812 	}
1813 
1814 	sfp->mod_phy = phy;
1815 
1816 	return 0;
1817 }
1818 
1819 static void sfp_sm_link_up(struct sfp *sfp)
1820 {
1821 	sfp_link_up(sfp->sfp_bus);
1822 	sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
1823 }
1824 
1825 static void sfp_sm_link_down(struct sfp *sfp)
1826 {
1827 	sfp_link_down(sfp->sfp_bus);
1828 }
1829 
1830 static void sfp_sm_link_check_los(struct sfp *sfp)
1831 {
1832 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1833 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1834 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1835 	bool los = false;
1836 
1837 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
1838 	 * are set, we assume that no LOS signal is available. If both are
1839 	 * set, we assume LOS is not implemented (and is meaningless.)
1840 	 */
1841 	if (los_options == los_inverted)
1842 		los = !(sfp->state & SFP_F_LOS);
1843 	else if (los_options == los_normal)
1844 		los = !!(sfp->state & SFP_F_LOS);
1845 
1846 	if (los)
1847 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
1848 	else
1849 		sfp_sm_link_up(sfp);
1850 }
1851 
1852 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
1853 {
1854 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1855 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1856 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1857 
1858 	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
1859 	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
1860 }
1861 
1862 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
1863 {
1864 	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
1865 	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
1866 	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
1867 
1868 	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
1869 	       (los_options == los_normal && event == SFP_E_LOS_LOW);
1870 }
1871 
1872 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
1873 {
1874 	if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
1875 		dev_err(sfp->dev,
1876 			"module persistently indicates fault, disabling\n");
1877 		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
1878 	} else {
1879 		if (warn)
1880 			dev_err(sfp->dev, "module transmit fault indicated\n");
1881 
1882 		sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
1883 	}
1884 }
1885 
1886 static int sfp_sm_add_mdio_bus(struct sfp *sfp)
1887 {
1888 	if (sfp->mdio_protocol != MDIO_I2C_NONE)
1889 		return sfp_i2c_mdiobus_create(sfp);
1890 
1891 	return 0;
1892 }
1893 
1894 /* Probe a SFP for a PHY device if the module supports copper - the PHY
1895  * normally sits at I2C bus address 0x56, and may either be a clause 22
1896  * or clause 45 PHY.
1897  *
1898  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
1899  * negotiation enabled, but some may be in 1000base-X - which is for the
1900  * PHY driver to determine.
1901  *
1902  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
1903  * mode according to the negotiated line speed.
1904  */
1905 static int sfp_sm_probe_for_phy(struct sfp *sfp)
1906 {
1907 	int err = 0;
1908 
1909 	switch (sfp->mdio_protocol) {
1910 	case MDIO_I2C_NONE:
1911 		break;
1912 
1913 	case MDIO_I2C_MARVELL_C22:
1914 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, false);
1915 		break;
1916 
1917 	case MDIO_I2C_C45:
1918 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR, true);
1919 		break;
1920 
1921 	case MDIO_I2C_ROLLBALL:
1922 		err = sfp_sm_probe_phy(sfp, SFP_PHY_ADDR_ROLLBALL, true);
1923 		break;
1924 	}
1925 
1926 	return err;
1927 }
1928 
1929 static int sfp_module_parse_power(struct sfp *sfp)
1930 {
1931 	u32 power_mW = 1000;
1932 	bool supports_a2;
1933 
1934 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
1935 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
1936 		power_mW = 1500;
1937 	/* Added in Rev 11.9, but there is no compliance code for this */
1938 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV11_4 &&
1939 	    sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
1940 		power_mW = 2000;
1941 
1942 	/* Power level 1 modules (max. 1W) are always supported. */
1943 	if (power_mW <= 1000) {
1944 		sfp->module_power_mW = power_mW;
1945 		return 0;
1946 	}
1947 
1948 	supports_a2 = sfp->id.ext.sff8472_compliance !=
1949 				SFP_SFF8472_COMPLIANCE_NONE ||
1950 		      sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
1951 
1952 	if (power_mW > sfp->max_power_mW) {
1953 		/* Module power specification exceeds the allowed maximum. */
1954 		if (!supports_a2) {
1955 			/* The module appears not to implement bus address
1956 			 * 0xa2, so assume that the module powers up in the
1957 			 * indicated mode.
1958 			 */
1959 			dev_err(sfp->dev,
1960 				"Host does not support %u.%uW modules\n",
1961 				power_mW / 1000, (power_mW / 100) % 10);
1962 			return -EINVAL;
1963 		} else {
1964 			dev_warn(sfp->dev,
1965 				 "Host does not support %u.%uW modules, module left in power mode 1\n",
1966 				 power_mW / 1000, (power_mW / 100) % 10);
1967 			return 0;
1968 		}
1969 	}
1970 
1971 	if (!supports_a2) {
1972 		/* The module power level is below the host maximum and the
1973 		 * module appears not to implement bus address 0xa2, so assume
1974 		 * that the module powers up in the indicated mode.
1975 		 */
1976 		return 0;
1977 	}
1978 
1979 	/* If the module requires a higher power mode, but also requires
1980 	 * an address change sequence, warn the user that the module may
1981 	 * not be functional.
1982 	 */
1983 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
1984 		dev_warn(sfp->dev,
1985 			 "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
1986 			 power_mW / 1000, (power_mW / 100) % 10);
1987 		return 0;
1988 	}
1989 
1990 	sfp->module_power_mW = power_mW;
1991 
1992 	return 0;
1993 }
1994 
1995 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
1996 {
1997 	int err;
1998 
1999 	err = sfp_modify_u8(sfp, true, SFP_EXT_STATUS,
2000 			    SFP_EXT_STATUS_PWRLVL_SELECT,
2001 			    enable ? SFP_EXT_STATUS_PWRLVL_SELECT : 0);
2002 	if (err != sizeof(u8)) {
2003 		dev_err(sfp->dev, "failed to %sable high power: %pe\n",
2004 			enable ? "en" : "dis", ERR_PTR(err));
2005 		return -EAGAIN;
2006 	}
2007 
2008 	if (enable)
2009 		dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
2010 			 sfp->module_power_mW / 1000,
2011 			 (sfp->module_power_mW / 100) % 10);
2012 
2013 	return 0;
2014 }
2015 
2016 static void sfp_module_parse_rate_select(struct sfp *sfp)
2017 {
2018 	u8 rate_id;
2019 
2020 	sfp->rs_threshold_kbd = 0;
2021 	sfp->rs_state_mask = 0;
2022 
2023 	if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_RATE_SELECT)))
2024 		/* No support for RateSelect */
2025 		return;
2026 
2027 	/* Default to INF-8074 RateSelect operation. The signalling threshold
2028 	 * rate is not well specified, so always select "Full Bandwidth", but
2029 	 * SFF-8079 reveals that it is understood that RS0 will be low for
2030 	 * 1.0625Gb/s and high for 2.125Gb/s. Choose a value half-way between.
2031 	 * This method exists prior to SFF-8472.
2032 	 */
2033 	sfp->rs_state_mask = SFP_F_RS0;
2034 	sfp->rs_threshold_kbd = 1594;
2035 
2036 	/* Parse the rate identifier, which is complicated due to history:
2037 	 * SFF-8472 rev 9.5 marks this field as reserved.
2038 	 * SFF-8079 references SFF-8472 rev 9.5 and defines bit 0. SFF-8472
2039 	 *  compliance is not required.
2040 	 * SFF-8472 rev 10.2 defines this field using values 0..4
2041 	 * SFF-8472 rev 11.0 redefines this field with bit 0 for SFF-8079
2042 	 * and even values.
2043 	 */
2044 	rate_id = sfp->id.base.rate_id;
2045 	if (rate_id == 0)
2046 		/* Unspecified */
2047 		return;
2048 
2049 	/* SFF-8472 rev 10.0..10.4 did not account for SFF-8079 using bit 0,
2050 	 * and allocated value 3 to SFF-8431 independent tx/rx rate select.
2051 	 * Convert this to a SFF-8472 rev 11.0 rate identifier.
2052 	 */
2053 	if (sfp->id.ext.sff8472_compliance >= SFP_SFF8472_COMPLIANCE_REV10_2 &&
2054 	    sfp->id.ext.sff8472_compliance < SFP_SFF8472_COMPLIANCE_REV11_0 &&
2055 	    rate_id == 3)
2056 		rate_id = SFF_RID_8431;
2057 
2058 	if (rate_id & SFF_RID_8079) {
2059 		/* SFF-8079 RateSelect / Application Select in conjunction with
2060 		 * SFF-8472 rev 9.5. SFF-8079 defines rate_id as a bitfield
2061 		 * with only bit 0 used, which takes precedence over SFF-8472.
2062 		 */
2063 		if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_APP_SELECT_SFF8079)) {
2064 			/* SFF-8079 Part 1 - rate selection between Fibre
2065 			 * Channel 1.0625/2.125/4.25 Gbd modes. Note that RS0
2066 			 * is high for 2125, so we have to subtract 1 to
2067 			 * include it.
2068 			 */
2069 			sfp->rs_threshold_kbd = 2125 - 1;
2070 			sfp->rs_state_mask = SFP_F_RS0;
2071 		}
2072 		return;
2073 	}
2074 
2075 	/* SFF-8472 rev 9.5 does not define the rate identifier */
2076 	if (sfp->id.ext.sff8472_compliance <= SFP_SFF8472_COMPLIANCE_REV9_5)
2077 		return;
2078 
2079 	/* SFF-8472 rev 11.0 defines rate_id as a numerical value which will
2080 	 * always have bit 0 clear due to SFF-8079's bitfield usage of rate_id.
2081 	 */
2082 	switch (rate_id) {
2083 	case SFF_RID_8431_RX_ONLY:
2084 		sfp->rs_threshold_kbd = 4250;
2085 		sfp->rs_state_mask = SFP_F_RS0;
2086 		break;
2087 
2088 	case SFF_RID_8431_TX_ONLY:
2089 		sfp->rs_threshold_kbd = 4250;
2090 		sfp->rs_state_mask = SFP_F_RS1;
2091 		break;
2092 
2093 	case SFF_RID_8431:
2094 		sfp->rs_threshold_kbd = 4250;
2095 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2096 		break;
2097 
2098 	case SFF_RID_10G8G:
2099 		sfp->rs_threshold_kbd = 9000;
2100 		sfp->rs_state_mask = SFP_F_RS0 | SFP_F_RS1;
2101 		break;
2102 	}
2103 }
2104 
2105 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
2106  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
2107  * not support multibyte reads from the EEPROM. Each multi-byte read
2108  * operation returns just one byte of EEPROM followed by zeros. There is
2109  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
2110  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
2111  * name and vendor id into EEPROM, so there is even no way to detect if
2112  * module is V-SOL V2801F. Therefore check for those zeros in the read
2113  * data and then based on check switch to reading EEPROM to one byte
2114  * at a time.
2115  */
2116 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
2117 {
2118 	size_t i, block_size = sfp->i2c_block_size;
2119 
2120 	/* Already using byte IO */
2121 	if (block_size == 1)
2122 		return false;
2123 
2124 	for (i = 1; i < len; i += block_size) {
2125 		if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
2126 			return false;
2127 	}
2128 	return true;
2129 }
2130 
2131 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
2132 {
2133 	u8 check;
2134 	int err;
2135 
2136 	if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
2137 	    id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
2138 	    id->base.connector != SFF8024_CONNECTOR_LC) {
2139 		dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
2140 		id->base.phys_id = SFF8024_ID_SFF_8472;
2141 		id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
2142 		id->base.connector = SFF8024_CONNECTOR_LC;
2143 		err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
2144 		if (err != 3) {
2145 			dev_err(sfp->dev,
2146 				"Failed to rewrite module EEPROM: %pe\n",
2147 				ERR_PTR(err));
2148 			return err;
2149 		}
2150 
2151 		/* Cotsworks modules have been found to require a delay between write operations. */
2152 		mdelay(50);
2153 
2154 		/* Update base structure checksum */
2155 		check = sfp_check(&id->base, sizeof(id->base) - 1);
2156 		err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
2157 		if (err != 1) {
2158 			dev_err(sfp->dev,
2159 				"Failed to update base structure checksum in fiber module EEPROM: %pe\n",
2160 				ERR_PTR(err));
2161 			return err;
2162 		}
2163 	}
2164 	return 0;
2165 }
2166 
2167 static int sfp_module_parse_sff8472(struct sfp *sfp)
2168 {
2169 	/* If the module requires address swap mode, warn about it */
2170 	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
2171 		dev_warn(sfp->dev,
2172 			 "module address swap to access page 0xA2 is not supported.\n");
2173 	else
2174 		sfp->have_a2 = true;
2175 
2176 	return 0;
2177 }
2178 
2179 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
2180 {
2181 	/* SFP module inserted - read I2C data */
2182 	struct sfp_eeprom_id id;
2183 	bool cotsworks_sfbg;
2184 	unsigned int mask;
2185 	bool cotsworks;
2186 	u8 check;
2187 	int ret;
2188 
2189 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2190 
2191 	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2192 	if (ret < 0) {
2193 		if (report)
2194 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2195 				ERR_PTR(ret));
2196 		return -EAGAIN;
2197 	}
2198 
2199 	if (ret != sizeof(id.base)) {
2200 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2201 		return -EAGAIN;
2202 	}
2203 
2204 	/* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
2205 	 * address 0x51 is just one byte at a time. Also SFF-8472 requires
2206 	 * that EEPROM supports atomic 16bit read operation for diagnostic
2207 	 * fields, so do not switch to one byte reading at a time unless it
2208 	 * is really required and we have no other option.
2209 	 */
2210 	if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
2211 		dev_info(sfp->dev,
2212 			 "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
2213 		dev_info(sfp->dev,
2214 			 "Switching to reading EEPROM to one byte at a time\n");
2215 		sfp->i2c_block_size = 1;
2216 
2217 		ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
2218 		if (ret < 0) {
2219 			if (report)
2220 				dev_err(sfp->dev,
2221 					"failed to read EEPROM: %pe\n",
2222 					ERR_PTR(ret));
2223 			return -EAGAIN;
2224 		}
2225 
2226 		if (ret != sizeof(id.base)) {
2227 			dev_err(sfp->dev, "EEPROM short read: %pe\n",
2228 				ERR_PTR(ret));
2229 			return -EAGAIN;
2230 		}
2231 	}
2232 
2233 	/* Cotsworks do not seem to update the checksums when they
2234 	 * do the final programming with the final module part number,
2235 	 * serial number and date code.
2236 	 */
2237 	cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
2238 	cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
2239 
2240 	/* Cotsworks SFF module EEPROM do not always have valid phys_id,
2241 	 * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
2242 	 * Cotsworks PN matches and bytes are not correct.
2243 	 */
2244 	if (cotsworks && cotsworks_sfbg) {
2245 		ret = sfp_cotsworks_fixup_check(sfp, &id);
2246 		if (ret < 0)
2247 			return ret;
2248 	}
2249 
2250 	/* Validate the checksum over the base structure */
2251 	check = sfp_check(&id.base, sizeof(id.base) - 1);
2252 	if (check != id.base.cc_base) {
2253 		if (cotsworks) {
2254 			dev_warn(sfp->dev,
2255 				 "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
2256 				 check, id.base.cc_base);
2257 		} else {
2258 			dev_err(sfp->dev,
2259 				"EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
2260 				check, id.base.cc_base);
2261 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2262 				       16, 1, &id, sizeof(id), true);
2263 			return -EINVAL;
2264 		}
2265 	}
2266 
2267 	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
2268 	if (ret < 0) {
2269 		if (report)
2270 			dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
2271 				ERR_PTR(ret));
2272 		return -EAGAIN;
2273 	}
2274 
2275 	if (ret != sizeof(id.ext)) {
2276 		dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
2277 		return -EAGAIN;
2278 	}
2279 
2280 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
2281 	if (check != id.ext.cc_ext) {
2282 		if (cotsworks) {
2283 			dev_warn(sfp->dev,
2284 				 "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
2285 				 check, id.ext.cc_ext);
2286 		} else {
2287 			dev_err(sfp->dev,
2288 				"EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
2289 				check, id.ext.cc_ext);
2290 			print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
2291 				       16, 1, &id, sizeof(id), true);
2292 			memset(&id.ext, 0, sizeof(id.ext));
2293 		}
2294 	}
2295 
2296 	sfp->id = id;
2297 
2298 	dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
2299 		 (int)sizeof(id.base.vendor_name), id.base.vendor_name,
2300 		 (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
2301 		 (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
2302 		 (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
2303 		 (int)sizeof(id.ext.datecode), id.ext.datecode);
2304 
2305 	/* Check whether we support this module */
2306 	if (!sfp->type->module_supported(&id)) {
2307 		dev_err(sfp->dev,
2308 			"module is not supported - phys id 0x%02x 0x%02x\n",
2309 			sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
2310 		return -EINVAL;
2311 	}
2312 
2313 	if (sfp->id.ext.sff8472_compliance != SFP_SFF8472_COMPLIANCE_NONE) {
2314 		ret = sfp_module_parse_sff8472(sfp);
2315 		if (ret < 0)
2316 			return ret;
2317 	}
2318 
2319 	/* Parse the module power requirement */
2320 	ret = sfp_module_parse_power(sfp);
2321 	if (ret < 0)
2322 		return ret;
2323 
2324 	sfp_module_parse_rate_select(sfp);
2325 
2326 	mask = SFP_F_PRESENT;
2327 	if (sfp->gpio[GPIO_TX_DISABLE])
2328 		mask |= SFP_F_TX_DISABLE;
2329 	if (sfp->gpio[GPIO_TX_FAULT])
2330 		mask |= SFP_F_TX_FAULT;
2331 	if (sfp->gpio[GPIO_LOS])
2332 		mask |= SFP_F_LOS;
2333 	if (sfp->gpio[GPIO_RS0])
2334 		mask |= SFP_F_RS0;
2335 	if (sfp->gpio[GPIO_RS1])
2336 		mask |= SFP_F_RS1;
2337 
2338 	sfp->module_t_start_up = T_START_UP;
2339 	sfp->module_t_wait = T_WAIT;
2340 	sfp->phy_t_retry = T_PHY_RETRY;
2341 
2342 	sfp->state_ignore_mask = 0;
2343 
2344 	if (sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SFI ||
2345 	    sfp->id.base.extended_cc == SFF8024_ECC_10GBASE_T_SR ||
2346 	    sfp->id.base.extended_cc == SFF8024_ECC_5GBASE_T ||
2347 	    sfp->id.base.extended_cc == SFF8024_ECC_2_5GBASE_T)
2348 		sfp->mdio_protocol = MDIO_I2C_C45;
2349 	else if (sfp->id.base.e1000_base_t)
2350 		sfp->mdio_protocol = MDIO_I2C_MARVELL_C22;
2351 	else
2352 		sfp->mdio_protocol = MDIO_I2C_NONE;
2353 
2354 	sfp->quirk = sfp_lookup_quirk(&id);
2355 
2356 	mutex_lock(&sfp->st_mutex);
2357 	/* Initialise state bits to use from hardware */
2358 	sfp->state_hw_mask = mask;
2359 
2360 	/* We want to drive the rate select pins that the module is using */
2361 	sfp->state_hw_drive |= sfp->rs_state_mask;
2362 
2363 	if (sfp->quirk && sfp->quirk->fixup)
2364 		sfp->quirk->fixup(sfp);
2365 
2366 	sfp->state_hw_mask &= ~sfp->state_ignore_mask;
2367 	mutex_unlock(&sfp->st_mutex);
2368 
2369 	return 0;
2370 }
2371 
2372 static void sfp_sm_mod_remove(struct sfp *sfp)
2373 {
2374 	if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
2375 		sfp_module_remove(sfp->sfp_bus);
2376 
2377 	sfp_hwmon_remove(sfp);
2378 
2379 	memset(&sfp->id, 0, sizeof(sfp->id));
2380 	sfp->module_power_mW = 0;
2381 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
2382 	sfp->have_a2 = false;
2383 
2384 	dev_info(sfp->dev, "module removed\n");
2385 }
2386 
2387 /* This state machine tracks the upstream's state */
2388 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
2389 {
2390 	switch (sfp->sm_dev_state) {
2391 	default:
2392 		if (event == SFP_E_DEV_ATTACH)
2393 			sfp->sm_dev_state = SFP_DEV_DOWN;
2394 		break;
2395 
2396 	case SFP_DEV_DOWN:
2397 		if (event == SFP_E_DEV_DETACH)
2398 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2399 		else if (event == SFP_E_DEV_UP)
2400 			sfp->sm_dev_state = SFP_DEV_UP;
2401 		break;
2402 
2403 	case SFP_DEV_UP:
2404 		if (event == SFP_E_DEV_DETACH)
2405 			sfp->sm_dev_state = SFP_DEV_DETACHED;
2406 		else if (event == SFP_E_DEV_DOWN)
2407 			sfp->sm_dev_state = SFP_DEV_DOWN;
2408 		break;
2409 	}
2410 }
2411 
2412 /* This state machine tracks the insert/remove state of the module, probes
2413  * the on-board EEPROM, and sets up the power level.
2414  */
2415 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
2416 {
2417 	int err;
2418 
2419 	/* Handle remove event globally, it resets this state machine */
2420 	if (event == SFP_E_REMOVE) {
2421 		if (sfp->sm_mod_state > SFP_MOD_PROBE)
2422 			sfp_sm_mod_remove(sfp);
2423 		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
2424 		return;
2425 	}
2426 
2427 	/* Handle device detach globally */
2428 	if (sfp->sm_dev_state < SFP_DEV_DOWN &&
2429 	    sfp->sm_mod_state > SFP_MOD_WAITDEV) {
2430 		if (sfp->module_power_mW > 1000 &&
2431 		    sfp->sm_mod_state > SFP_MOD_HPOWER)
2432 			sfp_sm_mod_hpower(sfp, false);
2433 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2434 		return;
2435 	}
2436 
2437 	switch (sfp->sm_mod_state) {
2438 	default:
2439 		if (event == SFP_E_INSERT) {
2440 			sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
2441 			sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
2442 			sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
2443 		}
2444 		break;
2445 
2446 	case SFP_MOD_PROBE:
2447 		/* Wait for T_PROBE_INIT to time out */
2448 		if (event != SFP_E_TIMEOUT)
2449 			break;
2450 
2451 		err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
2452 		if (err == -EAGAIN) {
2453 			if (sfp->sm_mod_tries_init &&
2454 			   --sfp->sm_mod_tries_init) {
2455 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2456 				break;
2457 			} else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
2458 				if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
2459 					dev_warn(sfp->dev,
2460 						 "please wait, module slow to respond\n");
2461 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
2462 				break;
2463 			}
2464 		}
2465 		if (err < 0) {
2466 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2467 			break;
2468 		}
2469 
2470 		/* Force a poll to re-read the hardware signal state after
2471 		 * sfp_sm_mod_probe() changed state_hw_mask.
2472 		 */
2473 		mod_delayed_work(system_wq, &sfp->poll, 1);
2474 
2475 		err = sfp_hwmon_insert(sfp);
2476 		if (err)
2477 			dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
2478 				 ERR_PTR(err));
2479 
2480 		sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
2481 		fallthrough;
2482 	case SFP_MOD_WAITDEV:
2483 		/* Ensure that the device is attached before proceeding */
2484 		if (sfp->sm_dev_state < SFP_DEV_DOWN)
2485 			break;
2486 
2487 		/* Report the module insertion to the upstream device */
2488 		err = sfp_module_insert(sfp->sfp_bus, &sfp->id,
2489 					sfp->quirk);
2490 		if (err < 0) {
2491 			sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2492 			break;
2493 		}
2494 
2495 		/* If this is a power level 1 module, we are done */
2496 		if (sfp->module_power_mW <= 1000)
2497 			goto insert;
2498 
2499 		sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
2500 		fallthrough;
2501 	case SFP_MOD_HPOWER:
2502 		/* Enable high power mode */
2503 		err = sfp_sm_mod_hpower(sfp, true);
2504 		if (err < 0) {
2505 			if (err != -EAGAIN) {
2506 				sfp_module_remove(sfp->sfp_bus);
2507 				sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
2508 			} else {
2509 				sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
2510 			}
2511 			break;
2512 		}
2513 
2514 		sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
2515 		break;
2516 
2517 	case SFP_MOD_WAITPWR:
2518 		/* Wait for T_HPOWER_LEVEL to time out */
2519 		if (event != SFP_E_TIMEOUT)
2520 			break;
2521 
2522 	insert:
2523 		sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
2524 		break;
2525 
2526 	case SFP_MOD_PRESENT:
2527 	case SFP_MOD_ERROR:
2528 		break;
2529 	}
2530 }
2531 
2532 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
2533 {
2534 	unsigned long timeout;
2535 	int ret;
2536 
2537 	/* Some events are global */
2538 	if (sfp->sm_state != SFP_S_DOWN &&
2539 	    (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2540 	     sfp->sm_dev_state != SFP_DEV_UP)) {
2541 		if (sfp->sm_state == SFP_S_LINK_UP &&
2542 		    sfp->sm_dev_state == SFP_DEV_UP)
2543 			sfp_sm_link_down(sfp);
2544 		if (sfp->sm_state > SFP_S_INIT)
2545 			sfp_module_stop(sfp->sfp_bus);
2546 		if (sfp->mod_phy)
2547 			sfp_sm_phy_detach(sfp);
2548 		if (sfp->i2c_mii)
2549 			sfp_i2c_mdiobus_destroy(sfp);
2550 		sfp_module_tx_disable(sfp);
2551 		sfp_soft_stop_poll(sfp);
2552 		sfp_sm_next(sfp, SFP_S_DOWN, 0);
2553 		return;
2554 	}
2555 
2556 	/* The main state machine */
2557 	switch (sfp->sm_state) {
2558 	case SFP_S_DOWN:
2559 		if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
2560 		    sfp->sm_dev_state != SFP_DEV_UP)
2561 			break;
2562 
2563 		/* Only use the soft state bits if we have access to the A2h
2564 		 * memory, which implies that we have some level of SFF-8472
2565 		 * compliance.
2566 		 */
2567 		if (sfp->have_a2)
2568 			sfp_soft_start_poll(sfp);
2569 
2570 		sfp_module_tx_enable(sfp);
2571 
2572 		/* Initialise the fault clearance retries */
2573 		sfp->sm_fault_retries = N_FAULT_INIT;
2574 
2575 		/* We need to check the TX_FAULT state, which is not defined
2576 		 * while TX_DISABLE is asserted. The earliest we want to do
2577 		 * anything (such as probe for a PHY) is 50ms (or more on
2578 		 * specific modules).
2579 		 */
2580 		sfp_sm_next(sfp, SFP_S_WAIT, sfp->module_t_wait);
2581 		break;
2582 
2583 	case SFP_S_WAIT:
2584 		if (event != SFP_E_TIMEOUT)
2585 			break;
2586 
2587 		if (sfp->state & SFP_F_TX_FAULT) {
2588 			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
2589 			 * from the TX_DISABLE deassertion for the module to
2590 			 * initialise, which is indicated by TX_FAULT
2591 			 * deasserting.
2592 			 */
2593 			timeout = sfp->module_t_start_up;
2594 			if (timeout > sfp->module_t_wait)
2595 				timeout -= sfp->module_t_wait;
2596 			else
2597 				timeout = 1;
2598 
2599 			sfp_sm_next(sfp, SFP_S_INIT, timeout);
2600 		} else {
2601 			/* TX_FAULT is not asserted, assume the module has
2602 			 * finished initialising.
2603 			 */
2604 			goto init_done;
2605 		}
2606 		break;
2607 
2608 	case SFP_S_INIT:
2609 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2610 			/* TX_FAULT is still asserted after t_init
2611 			 * or t_start_up, so assume there is a fault.
2612 			 */
2613 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
2614 				     sfp->sm_fault_retries == N_FAULT_INIT);
2615 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2616 	init_done:
2617 			/* Create mdiobus and start trying for PHY */
2618 			ret = sfp_sm_add_mdio_bus(sfp);
2619 			if (ret < 0) {
2620 				sfp_sm_next(sfp, SFP_S_FAIL, 0);
2621 				break;
2622 			}
2623 			sfp->sm_phy_retries = R_PHY_RETRY;
2624 			goto phy_probe;
2625 		}
2626 		break;
2627 
2628 	case SFP_S_INIT_PHY:
2629 		if (event != SFP_E_TIMEOUT)
2630 			break;
2631 	phy_probe:
2632 		/* TX_FAULT deasserted or we timed out with TX_FAULT
2633 		 * clear.  Probe for the PHY and check the LOS state.
2634 		 */
2635 		ret = sfp_sm_probe_for_phy(sfp);
2636 		if (ret == -ENODEV) {
2637 			if (--sfp->sm_phy_retries) {
2638 				sfp_sm_next(sfp, SFP_S_INIT_PHY,
2639 					    sfp->phy_t_retry);
2640 				dev_dbg(sfp->dev,
2641 					"no PHY detected, %u tries left\n",
2642 					sfp->sm_phy_retries);
2643 				break;
2644 			} else {
2645 				dev_info(sfp->dev, "no PHY detected\n");
2646 			}
2647 		} else if (ret) {
2648 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2649 			break;
2650 		}
2651 		if (sfp_module_start(sfp->sfp_bus)) {
2652 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
2653 			break;
2654 		}
2655 		sfp_sm_link_check_los(sfp);
2656 
2657 		/* Reset the fault retry count */
2658 		sfp->sm_fault_retries = N_FAULT;
2659 		break;
2660 
2661 	case SFP_S_INIT_TX_FAULT:
2662 		if (event == SFP_E_TIMEOUT) {
2663 			sfp_module_tx_fault_reset(sfp);
2664 			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
2665 		}
2666 		break;
2667 
2668 	case SFP_S_WAIT_LOS:
2669 		if (event == SFP_E_TX_FAULT)
2670 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2671 		else if (sfp_los_event_inactive(sfp, event))
2672 			sfp_sm_link_up(sfp);
2673 		break;
2674 
2675 	case SFP_S_LINK_UP:
2676 		if (event == SFP_E_TX_FAULT) {
2677 			sfp_sm_link_down(sfp);
2678 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
2679 		} else if (sfp_los_event_active(sfp, event)) {
2680 			sfp_sm_link_down(sfp);
2681 			sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
2682 		}
2683 		break;
2684 
2685 	case SFP_S_TX_FAULT:
2686 		if (event == SFP_E_TIMEOUT) {
2687 			sfp_module_tx_fault_reset(sfp);
2688 			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
2689 		}
2690 		break;
2691 
2692 	case SFP_S_REINIT:
2693 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
2694 			sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
2695 		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
2696 			dev_info(sfp->dev, "module transmit fault recovered\n");
2697 			sfp_sm_link_check_los(sfp);
2698 		}
2699 		break;
2700 
2701 	case SFP_S_TX_DISABLE:
2702 		break;
2703 	}
2704 }
2705 
2706 static void __sfp_sm_event(struct sfp *sfp, unsigned int event)
2707 {
2708 	dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
2709 		mod_state_to_str(sfp->sm_mod_state),
2710 		dev_state_to_str(sfp->sm_dev_state),
2711 		sm_state_to_str(sfp->sm_state),
2712 		event_to_str(event));
2713 
2714 	sfp_sm_device(sfp, event);
2715 	sfp_sm_module(sfp, event);
2716 	sfp_sm_main(sfp, event);
2717 
2718 	dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
2719 		mod_state_to_str(sfp->sm_mod_state),
2720 		dev_state_to_str(sfp->sm_dev_state),
2721 		sm_state_to_str(sfp->sm_state));
2722 }
2723 
2724 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
2725 {
2726 	mutex_lock(&sfp->sm_mutex);
2727 	__sfp_sm_event(sfp, event);
2728 	mutex_unlock(&sfp->sm_mutex);
2729 }
2730 
2731 static void sfp_attach(struct sfp *sfp)
2732 {
2733 	sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
2734 }
2735 
2736 static void sfp_detach(struct sfp *sfp)
2737 {
2738 	sfp_sm_event(sfp, SFP_E_DEV_DETACH);
2739 }
2740 
2741 static void sfp_start(struct sfp *sfp)
2742 {
2743 	sfp_sm_event(sfp, SFP_E_DEV_UP);
2744 }
2745 
2746 static void sfp_stop(struct sfp *sfp)
2747 {
2748 	sfp_sm_event(sfp, SFP_E_DEV_DOWN);
2749 }
2750 
2751 static void sfp_set_signal_rate(struct sfp *sfp, unsigned int rate_kbd)
2752 {
2753 	unsigned int set;
2754 
2755 	sfp->rate_kbd = rate_kbd;
2756 
2757 	if (rate_kbd > sfp->rs_threshold_kbd)
2758 		set = sfp->rs_state_mask;
2759 	else
2760 		set = 0;
2761 
2762 	sfp_mod_state(sfp, SFP_F_RS0 | SFP_F_RS1, set);
2763 }
2764 
2765 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
2766 {
2767 	/* locking... and check module is present */
2768 
2769 	if (sfp->id.ext.sff8472_compliance &&
2770 	    !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
2771 		modinfo->type = ETH_MODULE_SFF_8472;
2772 		modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
2773 	} else {
2774 		modinfo->type = ETH_MODULE_SFF_8079;
2775 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
2776 	}
2777 	return 0;
2778 }
2779 
2780 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
2781 			     u8 *data)
2782 {
2783 	unsigned int first, last, len;
2784 	int ret;
2785 
2786 	if (!(sfp->state & SFP_F_PRESENT))
2787 		return -ENODEV;
2788 
2789 	if (ee->len == 0)
2790 		return -EINVAL;
2791 
2792 	first = ee->offset;
2793 	last = ee->offset + ee->len;
2794 	if (first < ETH_MODULE_SFF_8079_LEN) {
2795 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
2796 		len -= first;
2797 
2798 		ret = sfp_read(sfp, false, first, data, len);
2799 		if (ret < 0)
2800 			return ret;
2801 
2802 		first += len;
2803 		data += len;
2804 	}
2805 	if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
2806 		len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
2807 		len -= first;
2808 		first -= ETH_MODULE_SFF_8079_LEN;
2809 
2810 		ret = sfp_read(sfp, true, first, data, len);
2811 		if (ret < 0)
2812 			return ret;
2813 	}
2814 	return 0;
2815 }
2816 
2817 static int sfp_module_eeprom_by_page(struct sfp *sfp,
2818 				     const struct ethtool_module_eeprom *page,
2819 				     struct netlink_ext_ack *extack)
2820 {
2821 	if (!(sfp->state & SFP_F_PRESENT))
2822 		return -ENODEV;
2823 
2824 	if (page->bank) {
2825 		NL_SET_ERR_MSG(extack, "Banks not supported");
2826 		return -EOPNOTSUPP;
2827 	}
2828 
2829 	if (page->page) {
2830 		NL_SET_ERR_MSG(extack, "Only page 0 supported");
2831 		return -EOPNOTSUPP;
2832 	}
2833 
2834 	if (page->i2c_address != 0x50 &&
2835 	    page->i2c_address != 0x51) {
2836 		NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
2837 		return -EOPNOTSUPP;
2838 	}
2839 
2840 	return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
2841 			page->data, page->length);
2842 };
2843 
2844 static const struct sfp_socket_ops sfp_module_ops = {
2845 	.attach = sfp_attach,
2846 	.detach = sfp_detach,
2847 	.start = sfp_start,
2848 	.stop = sfp_stop,
2849 	.set_signal_rate = sfp_set_signal_rate,
2850 	.module_info = sfp_module_info,
2851 	.module_eeprom = sfp_module_eeprom,
2852 	.module_eeprom_by_page = sfp_module_eeprom_by_page,
2853 };
2854 
2855 static void sfp_timeout(struct work_struct *work)
2856 {
2857 	struct sfp *sfp = container_of(work, struct sfp, timeout.work);
2858 
2859 	rtnl_lock();
2860 	sfp_sm_event(sfp, SFP_E_TIMEOUT);
2861 	rtnl_unlock();
2862 }
2863 
2864 static void sfp_check_state(struct sfp *sfp)
2865 {
2866 	unsigned int state, i, changed;
2867 
2868 	rtnl_lock();
2869 	mutex_lock(&sfp->st_mutex);
2870 	state = sfp_get_state(sfp);
2871 	changed = state ^ sfp->state;
2872 	changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
2873 
2874 	for (i = 0; i < GPIO_MAX; i++)
2875 		if (changed & BIT(i))
2876 			dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_names[i],
2877 				!!(sfp->state & BIT(i)), !!(state & BIT(i)));
2878 
2879 	state |= sfp->state & SFP_F_OUTPUTS;
2880 	sfp->state = state;
2881 	mutex_unlock(&sfp->st_mutex);
2882 
2883 	mutex_lock(&sfp->sm_mutex);
2884 	if (changed & SFP_F_PRESENT)
2885 		__sfp_sm_event(sfp, state & SFP_F_PRESENT ?
2886 				    SFP_E_INSERT : SFP_E_REMOVE);
2887 
2888 	if (changed & SFP_F_TX_FAULT)
2889 		__sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
2890 				    SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
2891 
2892 	if (changed & SFP_F_LOS)
2893 		__sfp_sm_event(sfp, state & SFP_F_LOS ?
2894 				    SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
2895 	mutex_unlock(&sfp->sm_mutex);
2896 	rtnl_unlock();
2897 }
2898 
2899 static irqreturn_t sfp_irq(int irq, void *data)
2900 {
2901 	struct sfp *sfp = data;
2902 
2903 	sfp_check_state(sfp);
2904 
2905 	return IRQ_HANDLED;
2906 }
2907 
2908 static void sfp_poll(struct work_struct *work)
2909 {
2910 	struct sfp *sfp = container_of(work, struct sfp, poll.work);
2911 
2912 	sfp_check_state(sfp);
2913 
2914 	// st_mutex doesn't need to be held here for state_soft_mask,
2915 	// it's unimportant if we race while reading this.
2916 	if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
2917 	    sfp->need_poll)
2918 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
2919 }
2920 
2921 static struct sfp *sfp_alloc(struct device *dev)
2922 {
2923 	struct sfp *sfp;
2924 
2925 	sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
2926 	if (!sfp)
2927 		return ERR_PTR(-ENOMEM);
2928 
2929 	sfp->dev = dev;
2930 	sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE;
2931 
2932 	mutex_init(&sfp->sm_mutex);
2933 	mutex_init(&sfp->st_mutex);
2934 	INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
2935 	INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
2936 
2937 	sfp_hwmon_init(sfp);
2938 
2939 	return sfp;
2940 }
2941 
2942 static void sfp_cleanup(void *data)
2943 {
2944 	struct sfp *sfp = data;
2945 
2946 	sfp_hwmon_exit(sfp);
2947 
2948 	cancel_delayed_work_sync(&sfp->poll);
2949 	cancel_delayed_work_sync(&sfp->timeout);
2950 	if (sfp->i2c_mii) {
2951 		mdiobus_unregister(sfp->i2c_mii);
2952 		mdiobus_free(sfp->i2c_mii);
2953 	}
2954 	if (sfp->i2c)
2955 		i2c_put_adapter(sfp->i2c);
2956 	kfree(sfp);
2957 }
2958 
2959 static int sfp_i2c_get(struct sfp *sfp)
2960 {
2961 	struct fwnode_handle *h;
2962 	struct i2c_adapter *i2c;
2963 	int err;
2964 
2965 	h = fwnode_find_reference(dev_fwnode(sfp->dev), "i2c-bus", 0);
2966 	if (IS_ERR(h)) {
2967 		dev_err(sfp->dev, "missing 'i2c-bus' property\n");
2968 		return -ENODEV;
2969 	}
2970 
2971 	i2c = i2c_get_adapter_by_fwnode(h);
2972 	if (!i2c) {
2973 		err = -EPROBE_DEFER;
2974 		goto put;
2975 	}
2976 
2977 	err = sfp_i2c_configure(sfp, i2c);
2978 	if (err)
2979 		i2c_put_adapter(i2c);
2980 put:
2981 	fwnode_handle_put(h);
2982 	return err;
2983 }
2984 
2985 static int sfp_probe(struct platform_device *pdev)
2986 {
2987 	const struct sff_data *sff;
2988 	char *sfp_irq_name;
2989 	struct sfp *sfp;
2990 	int err, i;
2991 
2992 	sfp = sfp_alloc(&pdev->dev);
2993 	if (IS_ERR(sfp))
2994 		return PTR_ERR(sfp);
2995 
2996 	platform_set_drvdata(pdev, sfp);
2997 
2998 	err = devm_add_action_or_reset(sfp->dev, sfp_cleanup, sfp);
2999 	if (err < 0)
3000 		return err;
3001 
3002 	sff = device_get_match_data(sfp->dev);
3003 	if (!sff)
3004 		sff = &sfp_data;
3005 
3006 	sfp->type = sff;
3007 
3008 	err = sfp_i2c_get(sfp);
3009 	if (err)
3010 		return err;
3011 
3012 	for (i = 0; i < GPIO_MAX; i++)
3013 		if (sff->gpios & BIT(i)) {
3014 			sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
3015 					   gpio_names[i], gpio_flags[i]);
3016 			if (IS_ERR(sfp->gpio[i]))
3017 				return PTR_ERR(sfp->gpio[i]);
3018 		}
3019 
3020 	sfp->state_hw_mask = SFP_F_PRESENT;
3021 	sfp->state_hw_drive = SFP_F_TX_DISABLE;
3022 
3023 	sfp->get_state = sfp_gpio_get_state;
3024 	sfp->set_state = sfp_gpio_set_state;
3025 
3026 	/* Modules that have no detect signal are always present */
3027 	if (!(sfp->gpio[GPIO_MODDEF0]))
3028 		sfp->get_state = sff_gpio_get_state;
3029 
3030 	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
3031 				 &sfp->max_power_mW);
3032 	if (sfp->max_power_mW < 1000) {
3033 		if (sfp->max_power_mW)
3034 			dev_warn(sfp->dev,
3035 				 "Firmware bug: host maximum power should be at least 1W\n");
3036 		sfp->max_power_mW = 1000;
3037 	}
3038 
3039 	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
3040 		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
3041 
3042 	/* Get the initial state, and always signal TX disable,
3043 	 * since the network interface will not be up.
3044 	 */
3045 	sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
3046 
3047 	if (sfp->gpio[GPIO_RS0] &&
3048 	    gpiod_get_value_cansleep(sfp->gpio[GPIO_RS0]))
3049 		sfp->state |= SFP_F_RS0;
3050 	sfp_set_state(sfp, sfp->state);
3051 	sfp_module_tx_disable(sfp);
3052 	if (sfp->state & SFP_F_PRESENT) {
3053 		rtnl_lock();
3054 		sfp_sm_event(sfp, SFP_E_INSERT);
3055 		rtnl_unlock();
3056 	}
3057 
3058 	for (i = 0; i < GPIO_MAX; i++) {
3059 		if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
3060 			continue;
3061 
3062 		sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
3063 		if (sfp->gpio_irq[i] < 0) {
3064 			sfp->gpio_irq[i] = 0;
3065 			sfp->need_poll = true;
3066 			continue;
3067 		}
3068 
3069 		sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
3070 					      "%s-%s", dev_name(sfp->dev),
3071 					      gpio_names[i]);
3072 
3073 		if (!sfp_irq_name)
3074 			return -ENOMEM;
3075 
3076 		err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
3077 						NULL, sfp_irq,
3078 						IRQF_ONESHOT |
3079 						IRQF_TRIGGER_RISING |
3080 						IRQF_TRIGGER_FALLING,
3081 						sfp_irq_name, sfp);
3082 		if (err) {
3083 			sfp->gpio_irq[i] = 0;
3084 			sfp->need_poll = true;
3085 		}
3086 	}
3087 
3088 	if (sfp->need_poll)
3089 		mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
3090 
3091 	/* We could have an issue in cases no Tx disable pin is available or
3092 	 * wired as modules using a laser as their light source will continue to
3093 	 * be active when the fiber is removed. This could be a safety issue and
3094 	 * we should at least warn the user about that.
3095 	 */
3096 	if (!sfp->gpio[GPIO_TX_DISABLE])
3097 		dev_warn(sfp->dev,
3098 			 "No tx_disable pin: SFP modules will always be emitting.\n");
3099 
3100 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
3101 	if (!sfp->sfp_bus)
3102 		return -ENOMEM;
3103 
3104 	sfp_debugfs_init(sfp);
3105 
3106 	return 0;
3107 }
3108 
3109 static void sfp_remove(struct platform_device *pdev)
3110 {
3111 	struct sfp *sfp = platform_get_drvdata(pdev);
3112 
3113 	sfp_debugfs_exit(sfp);
3114 	sfp_unregister_socket(sfp->sfp_bus);
3115 
3116 	rtnl_lock();
3117 	sfp_sm_event(sfp, SFP_E_REMOVE);
3118 	rtnl_unlock();
3119 }
3120 
3121 static void sfp_shutdown(struct platform_device *pdev)
3122 {
3123 	struct sfp *sfp = platform_get_drvdata(pdev);
3124 	int i;
3125 
3126 	for (i = 0; i < GPIO_MAX; i++) {
3127 		if (!sfp->gpio_irq[i])
3128 			continue;
3129 
3130 		devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
3131 	}
3132 
3133 	cancel_delayed_work_sync(&sfp->poll);
3134 	cancel_delayed_work_sync(&sfp->timeout);
3135 }
3136 
3137 static struct platform_driver sfp_driver = {
3138 	.probe = sfp_probe,
3139 	.remove_new = sfp_remove,
3140 	.shutdown = sfp_shutdown,
3141 	.driver = {
3142 		.name = "sfp",
3143 		.of_match_table = sfp_of_match,
3144 	},
3145 };
3146 
3147 static int sfp_init(void)
3148 {
3149 	poll_jiffies = msecs_to_jiffies(100);
3150 
3151 	return platform_driver_register(&sfp_driver);
3152 }
3153 module_init(sfp_init);
3154 
3155 static void sfp_exit(void)
3156 {
3157 	platform_driver_unregister(&sfp_driver);
3158 }
3159 module_exit(sfp_exit);
3160 
3161 MODULE_ALIAS("platform:sfp");
3162 MODULE_AUTHOR("Russell King");
3163 MODULE_LICENSE("GPL v2");
3164 MODULE_DESCRIPTION("SFP cage support");
3165