xref: /linux/drivers/net/pse-pd/tps23881.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for the TI TPS23881 PoE PSE Controller driver (I2C bus)
4  *
5  * Copyright (c) 2023 Bootlin, Kory Maincent <kory.maincent@bootlin.com>
6  */
7 
8 #include <linux/delay.h>
9 #include <linux/firmware.h>
10 #include <linux/i2c.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/platform_device.h>
14 #include <linux/pse-pd/pse.h>
15 
16 #define TPS23881_MAX_CHANS 8
17 
18 #define TPS23881_REG_PW_STATUS	0x10
19 #define TPS23881_REG_OP_MODE	0x12
20 #define TPS23881_OP_MODE_SEMIAUTO	0xaaaa
21 #define TPS23881_REG_DIS_EN	0x13
22 #define TPS23881_REG_DET_CLA_EN	0x14
23 #define TPS23881_REG_GEN_MASK	0x17
24 #define TPS23881_REG_NBITACC	BIT(5)
25 #define TPS23881_REG_PW_EN	0x19
26 #define TPS23881_REG_PORT_MAP	0x26
27 #define TPS23881_REG_PORT_POWER	0x29
28 #define TPS23881_REG_POEPLUS	0x40
29 #define TPS23881_REG_TPON	BIT(0)
30 #define TPS23881_REG_FWREV	0x41
31 #define TPS23881_REG_DEVID	0x43
32 #define TPS23881_REG_SRAM_CTRL	0x60
33 #define TPS23881_REG_SRAM_DATA	0x61
34 
35 struct tps23881_port_desc {
36 	u8 chan[2];
37 	bool is_4p;
38 };
39 
40 struct tps23881_priv {
41 	struct i2c_client *client;
42 	struct pse_controller_dev pcdev;
43 	struct device_node *np;
44 	struct tps23881_port_desc port[TPS23881_MAX_CHANS];
45 };
46 
47 static struct tps23881_priv *to_tps23881_priv(struct pse_controller_dev *pcdev)
48 {
49 	return container_of(pcdev, struct tps23881_priv, pcdev);
50 }
51 
52 static int tps23881_pi_enable(struct pse_controller_dev *pcdev, int id)
53 {
54 	struct tps23881_priv *priv = to_tps23881_priv(pcdev);
55 	struct i2c_client *client = priv->client;
56 	u8 chan;
57 	u16 val;
58 	int ret;
59 
60 	if (id >= TPS23881_MAX_CHANS)
61 		return -ERANGE;
62 
63 	ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
64 	if (ret < 0)
65 		return ret;
66 
67 	chan = priv->port[id].chan[0];
68 	if (chan < 4)
69 		val = (u16)(ret | BIT(chan));
70 	else
71 		val = (u16)(ret | BIT(chan + 4));
72 
73 	if (priv->port[id].is_4p) {
74 		chan = priv->port[id].chan[1];
75 		if (chan < 4)
76 			val |= BIT(chan);
77 		else
78 			val |= BIT(chan + 4);
79 	}
80 
81 	ret = i2c_smbus_write_word_data(client, TPS23881_REG_PW_EN, val);
82 	if (ret)
83 		return ret;
84 
85 	return 0;
86 }
87 
88 static int tps23881_pi_disable(struct pse_controller_dev *pcdev, int id)
89 {
90 	struct tps23881_priv *priv = to_tps23881_priv(pcdev);
91 	struct i2c_client *client = priv->client;
92 	u8 chan;
93 	u16 val;
94 	int ret;
95 
96 	if (id >= TPS23881_MAX_CHANS)
97 		return -ERANGE;
98 
99 	ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
100 	if (ret < 0)
101 		return ret;
102 
103 	chan = priv->port[id].chan[0];
104 	if (chan < 4)
105 		val = (u16)(ret | BIT(chan + 4));
106 	else
107 		val = (u16)(ret | BIT(chan + 8));
108 
109 	if (priv->port[id].is_4p) {
110 		chan = priv->port[id].chan[1];
111 		if (chan < 4)
112 			val |= BIT(chan + 4);
113 		else
114 			val |= BIT(chan + 8);
115 	}
116 
117 	ret = i2c_smbus_write_word_data(client, TPS23881_REG_PW_EN, val);
118 	if (ret)
119 		return ret;
120 
121 	return 0;
122 }
123 
124 static int tps23881_pi_is_enabled(struct pse_controller_dev *pcdev, int id)
125 {
126 	struct tps23881_priv *priv = to_tps23881_priv(pcdev);
127 	struct i2c_client *client = priv->client;
128 	bool enabled;
129 	u8 chan;
130 	int ret;
131 
132 	ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
133 	if (ret < 0)
134 		return ret;
135 
136 	chan = priv->port[id].chan[0];
137 	if (chan < 4)
138 		enabled = ret & BIT(chan);
139 	else
140 		enabled = ret & BIT(chan + 4);
141 
142 	if (priv->port[id].is_4p) {
143 		chan = priv->port[id].chan[1];
144 		if (chan < 4)
145 			enabled &= !!(ret & BIT(chan));
146 		else
147 			enabled &= !!(ret & BIT(chan + 4));
148 	}
149 
150 	/* Return enabled status only if both channel are on this state */
151 	return enabled;
152 }
153 
154 static int tps23881_ethtool_get_status(struct pse_controller_dev *pcdev,
155 				       unsigned long id,
156 				       struct netlink_ext_ack *extack,
157 				       struct pse_control_status *status)
158 {
159 	struct tps23881_priv *priv = to_tps23881_priv(pcdev);
160 	struct i2c_client *client = priv->client;
161 	bool enabled, delivering;
162 	u8 chan;
163 	int ret;
164 
165 	ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
166 	if (ret < 0)
167 		return ret;
168 
169 	chan = priv->port[id].chan[0];
170 	if (chan < 4) {
171 		enabled = ret & BIT(chan);
172 		delivering = ret & BIT(chan + 4);
173 	} else {
174 		enabled = ret & BIT(chan + 4);
175 		delivering = ret & BIT(chan + 8);
176 	}
177 
178 	if (priv->port[id].is_4p) {
179 		chan = priv->port[id].chan[1];
180 		if (chan < 4) {
181 			enabled &= !!(ret & BIT(chan));
182 			delivering &= !!(ret & BIT(chan + 4));
183 		} else {
184 			enabled &= !!(ret & BIT(chan + 4));
185 			delivering &= !!(ret & BIT(chan + 8));
186 		}
187 	}
188 
189 	/* Return delivering status only if both channel are on this state */
190 	if (delivering)
191 		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DELIVERING;
192 	else
193 		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DISABLED;
194 
195 	/* Return enabled status only if both channel are on this state */
196 	if (enabled)
197 		status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED;
198 	else
199 		status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED;
200 
201 	return 0;
202 }
203 
204 /* Parse managers subnode into a array of device node */
205 static int
206 tps23881_get_of_channels(struct tps23881_priv *priv,
207 			 struct device_node *chan_node[TPS23881_MAX_CHANS])
208 {
209 	struct device_node *channels_node, *node;
210 	int i, ret;
211 
212 	if (!priv->np)
213 		return -EINVAL;
214 
215 	channels_node = of_find_node_by_name(priv->np, "channels");
216 	if (!channels_node)
217 		return -EINVAL;
218 
219 	for_each_child_of_node(channels_node, node) {
220 		u32 chan_id;
221 
222 		if (!of_node_name_eq(node, "channel"))
223 			continue;
224 
225 		ret = of_property_read_u32(node, "reg", &chan_id);
226 		if (ret) {
227 			ret = -EINVAL;
228 			goto out;
229 		}
230 
231 		if (chan_id >= TPS23881_MAX_CHANS || chan_node[chan_id]) {
232 			dev_err(&priv->client->dev,
233 				"wrong number of port (%d)\n", chan_id);
234 			ret = -EINVAL;
235 			goto out;
236 		}
237 
238 		of_node_get(node);
239 		chan_node[chan_id] = node;
240 	}
241 
242 	of_node_put(channels_node);
243 	return 0;
244 
245 out:
246 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
247 		of_node_put(chan_node[i]);
248 		chan_node[i] = NULL;
249 	}
250 
251 	of_node_put(node);
252 	of_node_put(channels_node);
253 	return ret;
254 }
255 
256 struct tps23881_port_matrix {
257 	u8 pi_id;
258 	u8 lgcl_chan[2];
259 	u8 hw_chan[2];
260 	bool is_4p;
261 	bool exist;
262 };
263 
264 static int
265 tps23881_match_channel(const struct pse_pi_pairset *pairset,
266 		       struct device_node *chan_node[TPS23881_MAX_CHANS])
267 {
268 	int i;
269 
270 	/* Look on every channels */
271 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
272 		if (pairset->np == chan_node[i])
273 			return i;
274 	}
275 
276 	return -ENODEV;
277 }
278 
279 static bool
280 tps23881_is_chan_free(struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS],
281 		      int chan)
282 {
283 	int i;
284 
285 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
286 		if (port_matrix[i].exist &&
287 		    (port_matrix[i].hw_chan[0] == chan ||
288 		    port_matrix[i].hw_chan[1] == chan))
289 			return false;
290 	}
291 
292 	return true;
293 }
294 
295 /* Fill port matrix with the matching channels */
296 static int
297 tps23881_match_port_matrix(struct pse_pi *pi, int pi_id,
298 			   struct device_node *chan_node[TPS23881_MAX_CHANS],
299 			   struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS])
300 {
301 	int ret;
302 
303 	if (!pi->pairset[0].np)
304 		return 0;
305 
306 	ret = tps23881_match_channel(&pi->pairset[0], chan_node);
307 	if (ret < 0)
308 		return ret;
309 
310 	if (!tps23881_is_chan_free(port_matrix, ret)) {
311 		pr_err("tps23881: channel %d already used\n", ret);
312 		return -ENODEV;
313 	}
314 
315 	port_matrix[pi_id].hw_chan[0] = ret;
316 	port_matrix[pi_id].exist = true;
317 
318 	if (!pi->pairset[1].np)
319 		return 0;
320 
321 	ret = tps23881_match_channel(&pi->pairset[1], chan_node);
322 	if (ret < 0)
323 		return ret;
324 
325 	if (!tps23881_is_chan_free(port_matrix, ret)) {
326 		pr_err("tps23881: channel %d already used\n", ret);
327 		return -ENODEV;
328 	}
329 
330 	if (port_matrix[pi_id].hw_chan[0] / 4 != ret / 4) {
331 		pr_err("tps23881: 4-pair PSE can only be set within the same 4 ports group");
332 		return -ENODEV;
333 	}
334 
335 	port_matrix[pi_id].hw_chan[1] = ret;
336 	port_matrix[pi_id].is_4p = true;
337 
338 	return 0;
339 }
340 
341 static int
342 tps23881_get_unused_chan(struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS],
343 			 int port_cnt)
344 {
345 	bool used;
346 	int i, j;
347 
348 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
349 		used = false;
350 
351 		for (j = 0; j < port_cnt; j++) {
352 			if (port_matrix[j].hw_chan[0] == i) {
353 				used = true;
354 				break;
355 			}
356 
357 			if (port_matrix[j].is_4p &&
358 			    port_matrix[j].hw_chan[1] == i) {
359 				used = true;
360 				break;
361 			}
362 		}
363 
364 		if (!used)
365 			return i;
366 	}
367 
368 	return -ENODEV;
369 }
370 
371 /* Sort the port matrix to following particular hardware ports matrix
372  * specification of the tps23881. The device has two 4-ports groups and
373  * each 4-pair powered device has to be configured to use two consecutive
374  * logical channel in each 4 ports group (1 and 2 or 3 and 4). Also the
375  * hardware matrix has to be fully configured even with unused chan to be
376  * valid.
377  */
378 static int
379 tps23881_sort_port_matrix(struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS])
380 {
381 	struct tps23881_port_matrix tmp_port_matrix[TPS23881_MAX_CHANS] = {0};
382 	int i, ret, port_cnt = 0, cnt_4ch_grp1 = 0, cnt_4ch_grp2 = 4;
383 
384 	/* Configure 4p port matrix */
385 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
386 		int *cnt;
387 
388 		if (!port_matrix[i].exist || !port_matrix[i].is_4p)
389 			continue;
390 
391 		if (port_matrix[i].hw_chan[0] < 4)
392 			cnt = &cnt_4ch_grp1;
393 		else
394 			cnt = &cnt_4ch_grp2;
395 
396 		tmp_port_matrix[port_cnt].exist = true;
397 		tmp_port_matrix[port_cnt].is_4p = true;
398 		tmp_port_matrix[port_cnt].pi_id = i;
399 		tmp_port_matrix[port_cnt].hw_chan[0] = port_matrix[i].hw_chan[0];
400 		tmp_port_matrix[port_cnt].hw_chan[1] = port_matrix[i].hw_chan[1];
401 
402 		/* 4-pair ports have to be configured with consecutive
403 		 * logical channels 0 and 1, 2 and 3.
404 		 */
405 		tmp_port_matrix[port_cnt].lgcl_chan[0] = (*cnt)++;
406 		tmp_port_matrix[port_cnt].lgcl_chan[1] = (*cnt)++;
407 
408 		port_cnt++;
409 	}
410 
411 	/* Configure 2p port matrix */
412 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
413 		int *cnt;
414 
415 		if (!port_matrix[i].exist || port_matrix[i].is_4p)
416 			continue;
417 
418 		if (port_matrix[i].hw_chan[0] < 4)
419 			cnt = &cnt_4ch_grp1;
420 		else
421 			cnt = &cnt_4ch_grp2;
422 
423 		tmp_port_matrix[port_cnt].exist = true;
424 		tmp_port_matrix[port_cnt].pi_id = i;
425 		tmp_port_matrix[port_cnt].lgcl_chan[0] = (*cnt)++;
426 		tmp_port_matrix[port_cnt].hw_chan[0] = port_matrix[i].hw_chan[0];
427 
428 		port_cnt++;
429 	}
430 
431 	/* Complete the rest of the first 4 port group matrix even if
432 	 * channels are unused
433 	 */
434 	while (cnt_4ch_grp1 < 4) {
435 		ret = tps23881_get_unused_chan(tmp_port_matrix, port_cnt);
436 		if (ret < 0) {
437 			pr_err("tps23881: port matrix issue, no chan available\n");
438 			return ret;
439 		}
440 
441 		if (port_cnt >= TPS23881_MAX_CHANS) {
442 			pr_err("tps23881: wrong number of channels\n");
443 			return -ENODEV;
444 		}
445 		tmp_port_matrix[port_cnt].lgcl_chan[0] = cnt_4ch_grp1;
446 		tmp_port_matrix[port_cnt].hw_chan[0] = ret;
447 		cnt_4ch_grp1++;
448 		port_cnt++;
449 	}
450 
451 	/* Complete the rest of the second 4 port group matrix even if
452 	 * channels are unused
453 	 */
454 	while (cnt_4ch_grp2 < 8) {
455 		ret = tps23881_get_unused_chan(tmp_port_matrix, port_cnt);
456 		if (ret < 0) {
457 			pr_err("tps23881: port matrix issue, no chan available\n");
458 			return -ENODEV;
459 		}
460 
461 		if (port_cnt >= TPS23881_MAX_CHANS) {
462 			pr_err("tps23881: wrong number of channels\n");
463 			return -ENODEV;
464 		}
465 		tmp_port_matrix[port_cnt].lgcl_chan[0] = cnt_4ch_grp2;
466 		tmp_port_matrix[port_cnt].hw_chan[0] = ret;
467 		cnt_4ch_grp2++;
468 		port_cnt++;
469 	}
470 
471 	memcpy(port_matrix, tmp_port_matrix, sizeof(tmp_port_matrix));
472 
473 	return port_cnt;
474 }
475 
476 /* Write port matrix to the hardware port matrix and the software port
477  * matrix.
478  */
479 static int
480 tps23881_write_port_matrix(struct tps23881_priv *priv,
481 			   struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS],
482 			   int port_cnt)
483 {
484 	struct i2c_client *client = priv->client;
485 	u8 pi_id, lgcl_chan, hw_chan;
486 	u16 val = 0;
487 	int i, ret;
488 
489 	for (i = 0; i < port_cnt; i++) {
490 		pi_id = port_matrix[i].pi_id;
491 		lgcl_chan = port_matrix[i].lgcl_chan[0];
492 		hw_chan = port_matrix[i].hw_chan[0] % 4;
493 
494 		/* Set software port matrix for existing ports */
495 		if (port_matrix[i].exist)
496 			priv->port[pi_id].chan[0] = lgcl_chan;
497 
498 		/* Set hardware port matrix for all ports */
499 		val |= hw_chan << (lgcl_chan * 2);
500 
501 		if (!port_matrix[i].is_4p)
502 			continue;
503 
504 		lgcl_chan = port_matrix[i].lgcl_chan[1];
505 		hw_chan = port_matrix[i].hw_chan[1] % 4;
506 
507 		/* Set software port matrix for existing ports */
508 		if (port_matrix[i].exist) {
509 			priv->port[pi_id].is_4p = true;
510 			priv->port[pi_id].chan[1] = lgcl_chan;
511 		}
512 
513 		/* Set hardware port matrix for all ports */
514 		val |= hw_chan << (lgcl_chan * 2);
515 	}
516 
517 	/* Write hardware ports matrix */
518 	ret = i2c_smbus_write_word_data(client, TPS23881_REG_PORT_MAP, val);
519 	if (ret)
520 		return ret;
521 
522 	return 0;
523 }
524 
525 static int
526 tps23881_set_ports_conf(struct tps23881_priv *priv,
527 			struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS])
528 {
529 	struct i2c_client *client = priv->client;
530 	int i, ret;
531 	u16 val;
532 
533 	/* Set operating mode */
534 	ret = i2c_smbus_write_word_data(client, TPS23881_REG_OP_MODE,
535 					TPS23881_OP_MODE_SEMIAUTO);
536 	if (ret)
537 		return ret;
538 
539 	/* Disable DC disconnect */
540 	ret = i2c_smbus_write_word_data(client, TPS23881_REG_DIS_EN, 0x0);
541 	if (ret)
542 		return ret;
543 
544 	/* Set port power allocation */
545 	val = 0;
546 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
547 		if (!port_matrix[i].exist)
548 			continue;
549 
550 		if (port_matrix[i].is_4p)
551 			val |= 0xf << ((port_matrix[i].lgcl_chan[0] / 2) * 4);
552 		else
553 			val |= 0x3 << ((port_matrix[i].lgcl_chan[0] / 2) * 4);
554 	}
555 	ret = i2c_smbus_write_word_data(client, TPS23881_REG_PORT_POWER, val);
556 	if (ret)
557 		return ret;
558 
559 	/* Enable detection and classification */
560 	val = 0;
561 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
562 		if (!port_matrix[i].exist)
563 			continue;
564 
565 		val |= BIT(port_matrix[i].lgcl_chan[0]) |
566 		       BIT(port_matrix[i].lgcl_chan[0] + 4);
567 		if (port_matrix[i].is_4p)
568 			val |= BIT(port_matrix[i].lgcl_chan[1]) |
569 			       BIT(port_matrix[i].lgcl_chan[1] + 4);
570 	}
571 	ret = i2c_smbus_write_word_data(client, TPS23881_REG_DET_CLA_EN, val);
572 	if (ret)
573 		return ret;
574 
575 	return 0;
576 }
577 
578 static int
579 tps23881_set_ports_matrix(struct tps23881_priv *priv,
580 			  struct device_node *chan_node[TPS23881_MAX_CHANS])
581 {
582 	struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS] = {0};
583 	int i, ret;
584 
585 	/* Update with values for every PSE PIs */
586 	for (i = 0; i < TPS23881_MAX_CHANS; i++) {
587 		ret = tps23881_match_port_matrix(&priv->pcdev.pi[i], i,
588 						 chan_node, port_matrix);
589 		if (ret)
590 			return ret;
591 	}
592 
593 	ret = tps23881_sort_port_matrix(port_matrix);
594 	if (ret < 0)
595 		return ret;
596 
597 	ret = tps23881_write_port_matrix(priv, port_matrix, ret);
598 	if (ret)
599 		return ret;
600 
601 	ret = tps23881_set_ports_conf(priv, port_matrix);
602 	if (ret)
603 		return ret;
604 
605 	return 0;
606 }
607 
608 static int tps23881_setup_pi_matrix(struct pse_controller_dev *pcdev)
609 {
610 	struct device_node *chan_node[TPS23881_MAX_CHANS] = {NULL};
611 	struct tps23881_priv *priv = to_tps23881_priv(pcdev);
612 	int ret, i;
613 
614 	ret = tps23881_get_of_channels(priv, chan_node);
615 	if (ret < 0) {
616 		dev_warn(&priv->client->dev,
617 			 "Unable to parse port-matrix, default matrix will be used\n");
618 		return 0;
619 	}
620 
621 	ret = tps23881_set_ports_matrix(priv, chan_node);
622 
623 	for (i = 0; i < TPS23881_MAX_CHANS; i++)
624 		of_node_put(chan_node[i]);
625 
626 	return ret;
627 }
628 
629 static const struct pse_controller_ops tps23881_ops = {
630 	.setup_pi_matrix = tps23881_setup_pi_matrix,
631 	.pi_enable = tps23881_pi_enable,
632 	.pi_disable = tps23881_pi_disable,
633 	.pi_is_enabled = tps23881_pi_is_enabled,
634 	.ethtool_get_status = tps23881_ethtool_get_status,
635 };
636 
637 static const char fw_parity_name[] = "ti/tps23881/tps23881-parity-14.bin";
638 static const char fw_sram_name[] = "ti/tps23881/tps23881-sram-14.bin";
639 
640 struct tps23881_fw_conf {
641 	u8 reg;
642 	u8 val;
643 };
644 
645 static const struct tps23881_fw_conf tps23881_fw_parity_conf[] = {
646 	{.reg = 0x60, .val = 0x01},
647 	{.reg = 0x62, .val = 0x00},
648 	{.reg = 0x63, .val = 0x80},
649 	{.reg = 0x60, .val = 0xC4},
650 	{.reg = 0x1D, .val = 0xBC},
651 	{.reg = 0xD7, .val = 0x02},
652 	{.reg = 0x91, .val = 0x00},
653 	{.reg = 0x90, .val = 0x00},
654 	{.reg = 0xD7, .val = 0x00},
655 	{.reg = 0x1D, .val = 0x00},
656 	{ /* sentinel */ }
657 };
658 
659 static const struct tps23881_fw_conf tps23881_fw_sram_conf[] = {
660 	{.reg = 0x60, .val = 0xC5},
661 	{.reg = 0x62, .val = 0x00},
662 	{.reg = 0x63, .val = 0x80},
663 	{.reg = 0x60, .val = 0xC0},
664 	{.reg = 0x1D, .val = 0xBC},
665 	{.reg = 0xD7, .val = 0x02},
666 	{.reg = 0x91, .val = 0x00},
667 	{.reg = 0x90, .val = 0x00},
668 	{.reg = 0xD7, .val = 0x00},
669 	{.reg = 0x1D, .val = 0x00},
670 	{ /* sentinel */ }
671 };
672 
673 static int tps23881_flash_sram_fw_part(struct i2c_client *client,
674 				       const char *fw_name,
675 				       const struct tps23881_fw_conf *fw_conf)
676 {
677 	const struct firmware *fw = NULL;
678 	int i, ret;
679 
680 	ret = request_firmware(&fw, fw_name, &client->dev);
681 	if (ret)
682 		return ret;
683 
684 	dev_dbg(&client->dev, "Flashing %s\n", fw_name);
685 
686 	/* Prepare device for RAM download */
687 	while (fw_conf->reg) {
688 		ret = i2c_smbus_write_byte_data(client, fw_conf->reg,
689 						fw_conf->val);
690 		if (ret)
691 			goto out;
692 
693 		fw_conf++;
694 	}
695 
696 	/* Flash the firmware file */
697 	for (i = 0; i < fw->size; i++) {
698 		ret = i2c_smbus_write_byte_data(client,
699 						TPS23881_REG_SRAM_DATA,
700 						fw->data[i]);
701 		if (ret)
702 			goto out;
703 	}
704 
705 out:
706 	release_firmware(fw);
707 	return ret;
708 }
709 
710 static int tps23881_flash_sram_fw(struct i2c_client *client)
711 {
712 	int ret;
713 
714 	ret = tps23881_flash_sram_fw_part(client, fw_parity_name,
715 					  tps23881_fw_parity_conf);
716 	if (ret)
717 		return ret;
718 
719 	ret = tps23881_flash_sram_fw_part(client, fw_sram_name,
720 					  tps23881_fw_sram_conf);
721 	if (ret)
722 		return ret;
723 
724 	ret = i2c_smbus_write_byte_data(client, TPS23881_REG_SRAM_CTRL, 0x18);
725 	if (ret)
726 		return ret;
727 
728 	mdelay(12);
729 
730 	return 0;
731 }
732 
733 static int tps23881_i2c_probe(struct i2c_client *client)
734 {
735 	struct device *dev = &client->dev;
736 	struct tps23881_priv *priv;
737 	int ret;
738 	u8 val;
739 
740 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
741 		dev_err(dev, "i2c check functionality failed\n");
742 		return -ENXIO;
743 	}
744 
745 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
746 	if (!priv)
747 		return -ENOMEM;
748 
749 	ret = i2c_smbus_read_byte_data(client, TPS23881_REG_DEVID);
750 	if (ret < 0)
751 		return ret;
752 
753 	if (ret != 0x22) {
754 		dev_err(dev, "Wrong device ID\n");
755 		return -ENXIO;
756 	}
757 
758 	ret = tps23881_flash_sram_fw(client);
759 	if (ret < 0)
760 		return ret;
761 
762 	ret = i2c_smbus_read_byte_data(client, TPS23881_REG_FWREV);
763 	if (ret < 0)
764 		return ret;
765 
766 	dev_info(&client->dev, "Firmware revision 0x%x\n", ret);
767 
768 	/* Set configuration B, 16 bit access on a single device address */
769 	ret = i2c_smbus_read_byte_data(client, TPS23881_REG_GEN_MASK);
770 	if (ret < 0)
771 		return ret;
772 
773 	val = ret | TPS23881_REG_NBITACC;
774 	ret = i2c_smbus_write_byte_data(client, TPS23881_REG_GEN_MASK, val);
775 	if (ret)
776 		return ret;
777 
778 	priv->client = client;
779 	i2c_set_clientdata(client, priv);
780 	priv->np = dev->of_node;
781 
782 	priv->pcdev.owner = THIS_MODULE;
783 	priv->pcdev.ops = &tps23881_ops;
784 	priv->pcdev.dev = dev;
785 	priv->pcdev.types = ETHTOOL_PSE_C33;
786 	priv->pcdev.nr_lines = TPS23881_MAX_CHANS;
787 	ret = devm_pse_controller_register(dev, &priv->pcdev);
788 	if (ret) {
789 		return dev_err_probe(dev, ret,
790 				     "failed to register PSE controller\n");
791 	}
792 
793 	return ret;
794 }
795 
796 static const struct i2c_device_id tps23881_id[] = {
797 	{ "tps23881", 0 },
798 	{ },
799 };
800 MODULE_DEVICE_TABLE(i2c, tps23881_id);
801 
802 static const struct of_device_id tps23881_of_match[] = {
803 	{ .compatible = "ti,tps23881", },
804 	{ },
805 };
806 MODULE_DEVICE_TABLE(of, tps23881_of_match);
807 
808 static struct i2c_driver tps23881_driver = {
809 	.probe		= tps23881_i2c_probe,
810 	.id_table	= tps23881_id,
811 	.driver		= {
812 		.name		= "tps23881",
813 		.of_match_table = tps23881_of_match,
814 	},
815 };
816 module_i2c_driver(tps23881_driver);
817 
818 MODULE_AUTHOR("Kory Maincent <kory.maincent@bootlin.com>");
819 MODULE_DESCRIPTION("TI TPS23881 PoE PSE Controller driver");
820 MODULE_LICENSE("GPL");
821