1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for TI TPS6598x USB Power Delivery controller family
4  *
5  * Copyright (C) 2017, Intel Corporation
6  * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
7  */
8 
9 #include <linux/i2c.h>
10 #include <linux/acpi.h>
11 #include <linux/module.h>
12 #include <linux/regmap.h>
13 #include <linux/interrupt.h>
14 #include <linux/usb/typec.h>
15 
16 /* Register offsets */
17 #define TPS_REG_VID			0x00
18 #define TPS_REG_MODE			0x03
19 #define TPS_REG_CMD1			0x08
20 #define TPS_REG_DATA1			0x09
21 #define TPS_REG_INT_EVENT1		0x14
22 #define TPS_REG_INT_EVENT2		0x15
23 #define TPS_REG_INT_MASK1		0x16
24 #define TPS_REG_INT_MASK2		0x17
25 #define TPS_REG_INT_CLEAR1		0x18
26 #define TPS_REG_INT_CLEAR2		0x19
27 #define TPS_REG_STATUS			0x1a
28 #define TPS_REG_SYSTEM_CONF		0x28
29 #define TPS_REG_CTRL_CONF		0x29
30 #define TPS_REG_POWER_STATUS		0x3f
31 #define TPS_REG_RX_IDENTITY_SOP		0x48
32 
33 /* TPS_REG_INT_* bits */
34 #define TPS_REG_INT_PLUG_EVENT		BIT(3)
35 
36 /* TPS_REG_STATUS bits */
37 #define TPS_STATUS_PLUG_PRESENT		BIT(0)
38 #define TPS_STATUS_ORIENTATION		BIT(4)
39 #define TPS_STATUS_PORTROLE(s)		(!!((s) & BIT(5)))
40 #define TPS_STATUS_DATAROLE(s)		(!!((s) & BIT(6)))
41 #define TPS_STATUS_VCONN(s)		(!!((s) & BIT(7)))
42 
43 /* TPS_REG_SYSTEM_CONF bits */
44 #define TPS_SYSCONF_PORTINFO(c)		((c) & 7)
45 
46 enum {
47 	TPS_PORTINFO_SINK,
48 	TPS_PORTINFO_SINK_ACCESSORY,
49 	TPS_PORTINFO_DRP_UFP,
50 	TPS_PORTINFO_DRP_UFP_DRD,
51 	TPS_PORTINFO_DRP_DFP,
52 	TPS_PORTINFO_DRP_DFP_DRD,
53 	TPS_PORTINFO_SOURCE,
54 };
55 
56 /* TPS_REG_POWER_STATUS bits */
57 #define TPS_POWER_STATUS_SOURCESINK	BIT(1)
58 #define TPS_POWER_STATUS_PWROPMODE(p)	(((p) & GENMASK(3, 2)) >> 2)
59 
60 /* TPS_REG_RX_IDENTITY_SOP */
61 struct tps6598x_rx_identity_reg {
62 	u8 status;
63 	struct usb_pd_identity identity;
64 	u32 vdo[3];
65 } __packed;
66 
67 /* Standard Task return codes */
68 #define TPS_TASK_TIMEOUT		1
69 #define TPS_TASK_REJECTED		3
70 
71 enum {
72 	TPS_MODE_APP,
73 	TPS_MODE_BOOT,
74 	TPS_MODE_BIST,
75 	TPS_MODE_DISC,
76 };
77 
78 static const char *const modes[] = {
79 	[TPS_MODE_APP]	= "APP ",
80 	[TPS_MODE_BOOT]	= "BOOT",
81 	[TPS_MODE_BIST]	= "BIST",
82 	[TPS_MODE_DISC]	= "DISC",
83 };
84 
85 /* Unrecognized commands will be replaced with "!CMD" */
86 #define INVALID_CMD(_cmd_)		(_cmd_ == 0x444d4321)
87 
88 struct tps6598x {
89 	struct device *dev;
90 	struct regmap *regmap;
91 	struct mutex lock; /* device lock */
92 	u8 i2c_protocol:1;
93 
94 	struct typec_port *port;
95 	struct typec_partner *partner;
96 	struct usb_pd_identity partner_identity;
97 	struct typec_capability typec_cap;
98 };
99 
100 /*
101  * Max data bytes for Data1, Data2, and other registers. See ch 1.3.2:
102  * http://www.ti.com/lit/ug/slvuan1a/slvuan1a.pdf
103  */
104 #define TPS_MAX_LEN	64
105 
106 static int
tps6598x_block_read(struct tps6598x * tps,u8 reg,void * val,size_t len)107 tps6598x_block_read(struct tps6598x *tps, u8 reg, void *val, size_t len)
108 {
109 	u8 data[TPS_MAX_LEN + 1];
110 	int ret;
111 
112 	if (WARN_ON(len + 1 > sizeof(data)))
113 		return -EINVAL;
114 
115 	if (!tps->i2c_protocol)
116 		return regmap_raw_read(tps->regmap, reg, val, len);
117 
118 	ret = regmap_raw_read(tps->regmap, reg, data, sizeof(data));
119 	if (ret)
120 		return ret;
121 
122 	if (data[0] < len)
123 		return -EIO;
124 
125 	memcpy(val, &data[1], len);
126 	return 0;
127 }
128 
tps6598x_block_write(struct tps6598x * tps,u8 reg,const void * val,size_t len)129 static int tps6598x_block_write(struct tps6598x *tps, u8 reg,
130 				const void *val, size_t len)
131 {
132 	u8 data[TPS_MAX_LEN + 1];
133 
134 	if (!tps->i2c_protocol)
135 		return regmap_raw_write(tps->regmap, reg, val, len);
136 
137 	data[0] = len;
138 	memcpy(&data[1], val, len);
139 
140 	return regmap_raw_write(tps->regmap, reg, data, sizeof(data));
141 }
142 
tps6598x_read16(struct tps6598x * tps,u8 reg,u16 * val)143 static inline int tps6598x_read16(struct tps6598x *tps, u8 reg, u16 *val)
144 {
145 	return tps6598x_block_read(tps, reg, val, sizeof(u16));
146 }
147 
tps6598x_read32(struct tps6598x * tps,u8 reg,u32 * val)148 static inline int tps6598x_read32(struct tps6598x *tps, u8 reg, u32 *val)
149 {
150 	return tps6598x_block_read(tps, reg, val, sizeof(u32));
151 }
152 
tps6598x_read64(struct tps6598x * tps,u8 reg,u64 * val)153 static inline int tps6598x_read64(struct tps6598x *tps, u8 reg, u64 *val)
154 {
155 	return tps6598x_block_read(tps, reg, val, sizeof(u64));
156 }
157 
tps6598x_write16(struct tps6598x * tps,u8 reg,u16 val)158 static inline int tps6598x_write16(struct tps6598x *tps, u8 reg, u16 val)
159 {
160 	return tps6598x_block_write(tps, reg, &val, sizeof(u16));
161 }
162 
tps6598x_write32(struct tps6598x * tps,u8 reg,u32 val)163 static inline int tps6598x_write32(struct tps6598x *tps, u8 reg, u32 val)
164 {
165 	return tps6598x_block_write(tps, reg, &val, sizeof(u32));
166 }
167 
tps6598x_write64(struct tps6598x * tps,u8 reg,u64 val)168 static inline int tps6598x_write64(struct tps6598x *tps, u8 reg, u64 val)
169 {
170 	return tps6598x_block_write(tps, reg, &val, sizeof(u64));
171 }
172 
173 static inline int
tps6598x_write_4cc(struct tps6598x * tps,u8 reg,const char * val)174 tps6598x_write_4cc(struct tps6598x *tps, u8 reg, const char *val)
175 {
176 	return tps6598x_block_write(tps, reg, val, 4);
177 }
178 
tps6598x_read_partner_identity(struct tps6598x * tps)179 static int tps6598x_read_partner_identity(struct tps6598x *tps)
180 {
181 	struct tps6598x_rx_identity_reg id;
182 	int ret;
183 
184 	ret = tps6598x_block_read(tps, TPS_REG_RX_IDENTITY_SOP,
185 				  &id, sizeof(id));
186 	if (ret)
187 		return ret;
188 
189 	tps->partner_identity = id.identity;
190 
191 	return 0;
192 }
193 
tps6598x_connect(struct tps6598x * tps,u32 status)194 static int tps6598x_connect(struct tps6598x *tps, u32 status)
195 {
196 	struct typec_partner_desc desc;
197 	enum typec_pwr_opmode mode;
198 	u16 pwr_status;
199 	int ret;
200 
201 	if (tps->partner)
202 		return 0;
203 
204 	ret = tps6598x_read16(tps, TPS_REG_POWER_STATUS, &pwr_status);
205 	if (ret < 0)
206 		return ret;
207 
208 	mode = TPS_POWER_STATUS_PWROPMODE(pwr_status);
209 
210 	desc.usb_pd = mode == TYPEC_PWR_MODE_PD;
211 	desc.accessory = TYPEC_ACCESSORY_NONE; /* XXX: handle accessories */
212 	desc.identity = NULL;
213 
214 	if (desc.usb_pd) {
215 		ret = tps6598x_read_partner_identity(tps);
216 		if (ret)
217 			return ret;
218 		desc.identity = &tps->partner_identity;
219 	}
220 
221 	typec_set_pwr_opmode(tps->port, mode);
222 	typec_set_pwr_role(tps->port, TPS_STATUS_PORTROLE(status));
223 	typec_set_vconn_role(tps->port, TPS_STATUS_VCONN(status));
224 	typec_set_data_role(tps->port, TPS_STATUS_DATAROLE(status));
225 
226 	tps->partner = typec_register_partner(tps->port, &desc);
227 	if (IS_ERR(tps->partner))
228 		return PTR_ERR(tps->partner);
229 
230 	if (desc.identity)
231 		typec_partner_set_identity(tps->partner);
232 
233 	return 0;
234 }
235 
tps6598x_disconnect(struct tps6598x * tps,u32 status)236 static void tps6598x_disconnect(struct tps6598x *tps, u32 status)
237 {
238 	if (!IS_ERR(tps->partner))
239 		typec_unregister_partner(tps->partner);
240 	tps->partner = NULL;
241 	typec_set_pwr_opmode(tps->port, TYPEC_PWR_MODE_USB);
242 	typec_set_pwr_role(tps->port, TPS_STATUS_PORTROLE(status));
243 	typec_set_vconn_role(tps->port, TPS_STATUS_VCONN(status));
244 	typec_set_data_role(tps->port, TPS_STATUS_DATAROLE(status));
245 }
246 
tps6598x_exec_cmd(struct tps6598x * tps,const char * cmd,size_t in_len,u8 * in_data,size_t out_len,u8 * out_data)247 static int tps6598x_exec_cmd(struct tps6598x *tps, const char *cmd,
248 			     size_t in_len, u8 *in_data,
249 			     size_t out_len, u8 *out_data)
250 {
251 	unsigned long timeout;
252 	u32 val;
253 	int ret;
254 
255 	ret = tps6598x_read32(tps, TPS_REG_CMD1, &val);
256 	if (ret)
257 		return ret;
258 	if (val && !INVALID_CMD(val))
259 		return -EBUSY;
260 
261 	if (in_len) {
262 		ret = tps6598x_block_write(tps, TPS_REG_DATA1,
263 					   in_data, in_len);
264 		if (ret)
265 			return ret;
266 	}
267 
268 	ret = tps6598x_write_4cc(tps, TPS_REG_CMD1, cmd);
269 	if (ret < 0)
270 		return ret;
271 
272 	/* XXX: Using 1s for now, but it may not be enough for every command. */
273 	timeout = jiffies + msecs_to_jiffies(1000);
274 
275 	do {
276 		ret = tps6598x_read32(tps, TPS_REG_CMD1, &val);
277 		if (ret)
278 			return ret;
279 		if (INVALID_CMD(val))
280 			return -EINVAL;
281 
282 		if (time_is_before_jiffies(timeout))
283 			return -ETIMEDOUT;
284 	} while (val);
285 
286 	if (out_len) {
287 		ret = tps6598x_block_read(tps, TPS_REG_DATA1,
288 					  out_data, out_len);
289 		if (ret)
290 			return ret;
291 		val = out_data[0];
292 	} else {
293 		ret = tps6598x_block_read(tps, TPS_REG_DATA1, &val, sizeof(u8));
294 		if (ret)
295 			return ret;
296 	}
297 
298 	switch (val) {
299 	case TPS_TASK_TIMEOUT:
300 		return -ETIMEDOUT;
301 	case TPS_TASK_REJECTED:
302 		return -EPERM;
303 	default:
304 		break;
305 	}
306 
307 	return 0;
308 }
309 
310 static int
tps6598x_dr_set(const struct typec_capability * cap,enum typec_data_role role)311 tps6598x_dr_set(const struct typec_capability *cap, enum typec_data_role role)
312 {
313 	struct tps6598x *tps = container_of(cap, struct tps6598x, typec_cap);
314 	const char *cmd = (role == TYPEC_DEVICE) ? "SWUF" : "SWDF";
315 	u32 status;
316 	int ret;
317 
318 	mutex_lock(&tps->lock);
319 
320 	ret = tps6598x_exec_cmd(tps, cmd, 0, NULL, 0, NULL);
321 	if (ret)
322 		goto out_unlock;
323 
324 	ret = tps6598x_read32(tps, TPS_REG_STATUS, &status);
325 	if (ret)
326 		goto out_unlock;
327 
328 	if (role != TPS_STATUS_DATAROLE(status)) {
329 		ret = -EPROTO;
330 		goto out_unlock;
331 	}
332 
333 	typec_set_data_role(tps->port, role);
334 
335 out_unlock:
336 	mutex_unlock(&tps->lock);
337 
338 	return ret;
339 }
340 
341 static int
tps6598x_pr_set(const struct typec_capability * cap,enum typec_role role)342 tps6598x_pr_set(const struct typec_capability *cap, enum typec_role role)
343 {
344 	struct tps6598x *tps = container_of(cap, struct tps6598x, typec_cap);
345 	const char *cmd = (role == TYPEC_SINK) ? "SWSk" : "SWSr";
346 	u32 status;
347 	int ret;
348 
349 	mutex_lock(&tps->lock);
350 
351 	ret = tps6598x_exec_cmd(tps, cmd, 0, NULL, 0, NULL);
352 	if (ret)
353 		goto out_unlock;
354 
355 	ret = tps6598x_read32(tps, TPS_REG_STATUS, &status);
356 	if (ret)
357 		goto out_unlock;
358 
359 	if (role != TPS_STATUS_PORTROLE(status)) {
360 		ret = -EPROTO;
361 		goto out_unlock;
362 	}
363 
364 	typec_set_pwr_role(tps->port, role);
365 
366 out_unlock:
367 	mutex_unlock(&tps->lock);
368 
369 	return ret;
370 }
371 
tps6598x_interrupt(int irq,void * data)372 static irqreturn_t tps6598x_interrupt(int irq, void *data)
373 {
374 	struct tps6598x *tps = data;
375 	u64 event1;
376 	u64 event2;
377 	u32 status;
378 	int ret;
379 
380 	mutex_lock(&tps->lock);
381 
382 	ret = tps6598x_read64(tps, TPS_REG_INT_EVENT1, &event1);
383 	ret |= tps6598x_read64(tps, TPS_REG_INT_EVENT2, &event2);
384 	if (ret) {
385 		dev_err(tps->dev, "%s: failed to read events\n", __func__);
386 		goto err_unlock;
387 	}
388 
389 	ret = tps6598x_read32(tps, TPS_REG_STATUS, &status);
390 	if (ret) {
391 		dev_err(tps->dev, "%s: failed to read status\n", __func__);
392 		goto err_clear_ints;
393 	}
394 
395 	/* Handle plug insert or removal */
396 	if ((event1 | event2) & TPS_REG_INT_PLUG_EVENT) {
397 		if (status & TPS_STATUS_PLUG_PRESENT) {
398 			ret = tps6598x_connect(tps, status);
399 			if (ret)
400 				dev_err(tps->dev,
401 					"failed to register partner\n");
402 		} else {
403 			tps6598x_disconnect(tps, status);
404 		}
405 	}
406 
407 err_clear_ints:
408 	tps6598x_write64(tps, TPS_REG_INT_CLEAR1, event1);
409 	tps6598x_write64(tps, TPS_REG_INT_CLEAR2, event2);
410 
411 err_unlock:
412 	mutex_unlock(&tps->lock);
413 
414 	return IRQ_HANDLED;
415 }
416 
tps6598x_check_mode(struct tps6598x * tps)417 static int tps6598x_check_mode(struct tps6598x *tps)
418 {
419 	char mode[5] = { };
420 	int ret;
421 
422 	ret = tps6598x_read32(tps, TPS_REG_MODE, (void *)mode);
423 	if (ret)
424 		return ret;
425 
426 	switch (match_string(modes, ARRAY_SIZE(modes), mode)) {
427 	case TPS_MODE_APP:
428 		return 0;
429 	case TPS_MODE_BOOT:
430 		dev_warn(tps->dev, "dead-battery condition\n");
431 		return 0;
432 	case TPS_MODE_BIST:
433 	case TPS_MODE_DISC:
434 	default:
435 		dev_err(tps->dev, "controller in unsupported mode \"%s\"\n",
436 			mode);
437 		break;
438 	}
439 
440 	return -ENODEV;
441 }
442 
443 static const struct regmap_config tps6598x_regmap_config = {
444 	.reg_bits = 8,
445 	.val_bits = 8,
446 	.max_register = 0x7F,
447 };
448 
tps6598x_probe(struct i2c_client * client)449 static int tps6598x_probe(struct i2c_client *client)
450 {
451 	struct tps6598x *tps;
452 	u32 status;
453 	u32 conf;
454 	u32 vid;
455 	int ret;
456 
457 	tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
458 	if (!tps)
459 		return -ENOMEM;
460 
461 	mutex_init(&tps->lock);
462 	tps->dev = &client->dev;
463 
464 	tps->regmap = devm_regmap_init_i2c(client, &tps6598x_regmap_config);
465 	if (IS_ERR(tps->regmap))
466 		return PTR_ERR(tps->regmap);
467 
468 	ret = tps6598x_read32(tps, TPS_REG_VID, &vid);
469 	if (ret < 0 || !vid)
470 		return -ENODEV;
471 
472 	/*
473 	 * Checking can the adapter handle SMBus protocol. If it can not, the
474 	 * driver needs to take care of block reads separately.
475 	 *
476 	 * FIXME: Testing with I2C_FUNC_I2C. regmap-i2c uses I2C protocol
477 	 * unconditionally if the adapter has I2C_FUNC_I2C set.
478 	 */
479 	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
480 		tps->i2c_protocol = true;
481 
482 	/* Make sure the controller has application firmware running */
483 	ret = tps6598x_check_mode(tps);
484 	if (ret)
485 		return ret;
486 
487 	ret = tps6598x_read32(tps, TPS_REG_STATUS, &status);
488 	if (ret < 0)
489 		return ret;
490 
491 	ret = tps6598x_read32(tps, TPS_REG_SYSTEM_CONF, &conf);
492 	if (ret < 0)
493 		return ret;
494 
495 	tps->typec_cap.revision = USB_TYPEC_REV_1_2;
496 	tps->typec_cap.pd_revision = 0x200;
497 	tps->typec_cap.prefer_role = TYPEC_NO_PREFERRED_ROLE;
498 	tps->typec_cap.pr_set = tps6598x_pr_set;
499 	tps->typec_cap.dr_set = tps6598x_dr_set;
500 
501 	switch (TPS_SYSCONF_PORTINFO(conf)) {
502 	case TPS_PORTINFO_SINK_ACCESSORY:
503 	case TPS_PORTINFO_SINK:
504 		tps->typec_cap.type = TYPEC_PORT_SNK;
505 		tps->typec_cap.data = TYPEC_PORT_UFP;
506 		break;
507 	case TPS_PORTINFO_DRP_UFP_DRD:
508 	case TPS_PORTINFO_DRP_DFP_DRD:
509 		tps->typec_cap.type = TYPEC_PORT_DRP;
510 		tps->typec_cap.data = TYPEC_PORT_DRD;
511 		break;
512 	case TPS_PORTINFO_DRP_UFP:
513 		tps->typec_cap.type = TYPEC_PORT_DRP;
514 		tps->typec_cap.data = TYPEC_PORT_UFP;
515 		break;
516 	case TPS_PORTINFO_DRP_DFP:
517 		tps->typec_cap.type = TYPEC_PORT_DRP;
518 		tps->typec_cap.data = TYPEC_PORT_DFP;
519 		break;
520 	case TPS_PORTINFO_SOURCE:
521 		tps->typec_cap.type = TYPEC_PORT_SRC;
522 		tps->typec_cap.data = TYPEC_PORT_DFP;
523 		break;
524 	default:
525 		return -ENODEV;
526 	}
527 
528 	tps->port = typec_register_port(&client->dev, &tps->typec_cap);
529 	if (IS_ERR(tps->port))
530 		return PTR_ERR(tps->port);
531 
532 	if (status & TPS_STATUS_PLUG_PRESENT) {
533 		ret = tps6598x_connect(tps, status);
534 		if (ret)
535 			dev_err(&client->dev, "failed to register partner\n");
536 	}
537 
538 	ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
539 					tps6598x_interrupt,
540 					IRQF_SHARED | IRQF_ONESHOT,
541 					dev_name(&client->dev), tps);
542 	if (ret) {
543 		tps6598x_disconnect(tps, 0);
544 		typec_unregister_port(tps->port);
545 		return ret;
546 	}
547 
548 	i2c_set_clientdata(client, tps);
549 
550 	return 0;
551 }
552 
tps6598x_remove(struct i2c_client * client)553 static int tps6598x_remove(struct i2c_client *client)
554 {
555 	struct tps6598x *tps = i2c_get_clientdata(client);
556 
557 	tps6598x_disconnect(tps, 0);
558 	typec_unregister_port(tps->port);
559 
560 	return 0;
561 }
562 
563 static const struct i2c_device_id tps6598x_id[] = {
564 	{ "tps6598x" },
565 	{ }
566 };
567 MODULE_DEVICE_TABLE(i2c, tps6598x_id);
568 
569 static struct i2c_driver tps6598x_i2c_driver = {
570 	.driver = {
571 		.name = "tps6598x",
572 	},
573 	.probe_new = tps6598x_probe,
574 	.remove = tps6598x_remove,
575 	.id_table = tps6598x_id,
576 };
577 module_i2c_driver(tps6598x_i2c_driver);
578 
579 MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
580 MODULE_LICENSE("GPL v2");
581 MODULE_DESCRIPTION("TI TPS6598x USB Power Delivery Controller Driver");
582