summaryrefslogtreecommitdiff
path: root/drivers/extcon/extcon-usbc-tusb320.c
blob: b408ce989c223900878be758ba44c9237a47966c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
// SPDX-License-Identifier: GPL-2.0
/*
 * drivers/extcon/extcon-tusb320.c - TUSB320 extcon driver
 *
 * Copyright (C) 2020 National Instruments Corporation
 * Author: Michael Auchter <michael.auchter@ni.com>
 */

#include <linux/bitfield.h>
#include <linux/extcon-provider.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/usb/typec.h>

#define TUSB320_REG8				0x8
#define TUSB320_REG8_CURRENT_MODE_ADVERTISE	GENMASK(7, 6)
#define TUSB320_REG8_CURRENT_MODE_ADVERTISE_USB	0x0
#define TUSB320_REG8_CURRENT_MODE_ADVERTISE_15A	0x1
#define TUSB320_REG8_CURRENT_MODE_ADVERTISE_30A	0x2
#define TUSB320_REG8_CURRENT_MODE_DETECT	GENMASK(5, 4)
#define TUSB320_REG8_CURRENT_MODE_DETECT_DEF	0x0
#define TUSB320_REG8_CURRENT_MODE_DETECT_MED	0x1
#define TUSB320_REG8_CURRENT_MODE_DETECT_ACC	0x2
#define TUSB320_REG8_CURRENT_MODE_DETECT_HI	0x3
#define TUSB320_REG8_ACCESSORY_CONNECTED	GENMASK(3, 2)
#define TUSB320_REG8_ACCESSORY_CONNECTED_NONE	0x0
#define TUSB320_REG8_ACCESSORY_CONNECTED_AUDIO	0x4
#define TUSB320_REG8_ACCESSORY_CONNECTED_ACC	0x5
#define TUSB320_REG8_ACCESSORY_CONNECTED_DEBUG	0x6
#define TUSB320_REG8_ACTIVE_CABLE_DETECTION	BIT(0)

#define TUSB320_REG9				0x9
#define TUSB320_REG9_ATTACHED_STATE_SHIFT	6
#define TUSB320_REG9_ATTACHED_STATE_MASK	0x3
#define TUSB320_REG9_CABLE_DIRECTION		BIT(5)
#define TUSB320_REG9_INTERRUPT_STATUS		BIT(4)

#define TUSB320_REGA				0xa
#define TUSB320L_REGA_DISABLE_TERM		BIT(0)
#define TUSB320_REGA_I2C_SOFT_RESET		BIT(3)
#define TUSB320_REGA_MODE_SELECT_SHIFT		4
#define TUSB320_REGA_MODE_SELECT_MASK		0x3

#define TUSB320L_REGA0_REVISION			0xa0

enum tusb320_attached_state {
	TUSB320_ATTACHED_STATE_NONE,
	TUSB320_ATTACHED_STATE_DFP,
	TUSB320_ATTACHED_STATE_UFP,
	TUSB320_ATTACHED_STATE_ACC,
};

enum tusb320_mode {
	TUSB320_MODE_PORT,
	TUSB320_MODE_UFP,
	TUSB320_MODE_DFP,
	TUSB320_MODE_DRP,
};

struct tusb320_priv;

struct tusb320_ops {
	int (*set_mode)(struct tusb320_priv *priv, enum tusb320_mode mode);
	int (*get_revision)(struct tusb320_priv *priv, unsigned int *revision);
};

struct tusb320_priv {
	struct device *dev;
	struct regmap *regmap;
	struct extcon_dev *edev;
	struct tusb320_ops *ops;
	enum tusb320_attached_state state;
	struct typec_port *port;
	struct typec_capability	cap;
	enum typec_port_type port_type;
	enum typec_pwr_opmode pwr_opmode;
};

static const char * const tusb_attached_states[] = {
	[TUSB320_ATTACHED_STATE_NONE] = "not attached",
	[TUSB320_ATTACHED_STATE_DFP]  = "downstream facing port",
	[TUSB320_ATTACHED_STATE_UFP]  = "upstream facing port",
	[TUSB320_ATTACHED_STATE_ACC]  = "accessory",
};

static const unsigned int tusb320_extcon_cable[] = {
	EXTCON_USB,
	EXTCON_USB_HOST,
	EXTCON_NONE,
};

static int tusb320_check_signature(struct tusb320_priv *priv)
{
	static const char sig[] = { '\0', 'T', 'U', 'S', 'B', '3', '2', '0' };
	unsigned val;
	int i, ret;

	for (i = 0; i < sizeof(sig); i++) {
		ret = regmap_read(priv->regmap, sizeof(sig) - 1 - i, &val);
		if (ret < 0)
			return ret;
		if (val != sig[i]) {
			dev_err(priv->dev, "signature mismatch!\n");
			return -ENODEV;
		}
	}

	return 0;
}

static int tusb320_set_mode(struct tusb320_priv *priv, enum tusb320_mode mode)
{
	int ret;

	/* Mode cannot be changed while cable is attached */
	if (priv->state != TUSB320_ATTACHED_STATE_NONE)
		return -EBUSY;

	/* Write mode */
	ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
		TUSB320_REGA_MODE_SELECT_MASK << TUSB320_REGA_MODE_SELECT_SHIFT,
		mode << TUSB320_REGA_MODE_SELECT_SHIFT);
	if (ret) {
		dev_err(priv->dev, "failed to write mode: %d\n", ret);
		return ret;
	}

	return 0;
}

static int tusb320l_set_mode(struct tusb320_priv *priv, enum tusb320_mode mode)
{
	int ret;

	/* Disable CC state machine */
	ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
		TUSB320L_REGA_DISABLE_TERM, 1);
	if (ret) {
		dev_err(priv->dev,
			"failed to disable CC state machine: %d\n", ret);
		return ret;
	}

	/* Write mode */
	ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
		TUSB320_REGA_MODE_SELECT_MASK << TUSB320_REGA_MODE_SELECT_SHIFT,
		mode << TUSB320_REGA_MODE_SELECT_SHIFT);
	if (ret) {
		dev_err(priv->dev, "failed to write mode: %d\n", ret);
		goto err;
	}

	msleep(5);
err:
	/* Re-enable CC state machine */
	ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
		TUSB320L_REGA_DISABLE_TERM, 0);
	if (ret)
		dev_err(priv->dev,
			"failed to re-enable CC state machine: %d\n", ret);

	return ret;
}

static int tusb320_reset(struct tusb320_priv *priv)
{
	int ret;

	/* Set mode to default (follow PORT pin) */
	ret = priv->ops->set_mode(priv, TUSB320_MODE_PORT);
	if (ret && ret != -EBUSY) {
		dev_err(priv->dev,
			"failed to set mode to PORT: %d\n", ret);
		return ret;
	}

	/* Perform soft reset */
	ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
			TUSB320_REGA_I2C_SOFT_RESET, 1);
	if (ret) {
		dev_err(priv->dev,
			"failed to write soft reset bit: %d\n", ret);
		return ret;
	}

	/* Wait for chip to go through reset */
	msleep(95);

	return 0;
}

static int tusb320l_get_revision(struct tusb320_priv *priv, unsigned int *revision)
{
	return regmap_read(priv->regmap, TUSB320L_REGA0_REVISION, revision);
}

static struct tusb320_ops tusb320_ops = {
	.set_mode = tusb320_set_mode,
};

static struct tusb320_ops tusb320l_ops = {
	.set_mode = tusb320l_set_mode,
	.get_revision = tusb320l_get_revision,
};

static int tusb320_set_adv_pwr_mode(struct tusb320_priv *priv)
{
	u8 mode;

	if (priv->pwr_opmode == TYPEC_PWR_MODE_USB)
		mode = TUSB320_REG8_CURRENT_MODE_ADVERTISE_USB;
	else if (priv->pwr_opmode == TYPEC_PWR_MODE_1_5A)
		mode = TUSB320_REG8_CURRENT_MODE_ADVERTISE_15A;
	else if (priv->pwr_opmode == TYPEC_PWR_MODE_3_0A)
		mode = TUSB320_REG8_CURRENT_MODE_ADVERTISE_30A;
	else	/* No other mode is supported. */
		return -EINVAL;

	return regmap_write_bits(priv->regmap, TUSB320_REG8,
				 TUSB320_REG8_CURRENT_MODE_ADVERTISE,
				 FIELD_PREP(TUSB320_REG8_CURRENT_MODE_ADVERTISE,
					    mode));
}

static int tusb320_port_type_set(struct typec_port *port,
				 enum typec_port_type type)
{
	struct tusb320_priv *priv = typec_get_drvdata(port);

	if (type == TYPEC_PORT_SRC)
		return priv->ops->set_mode(priv, TUSB320_MODE_DFP);
	else if (type == TYPEC_PORT_SNK)
		return priv->ops->set_mode(priv, TUSB320_MODE_UFP);
	else if (type == TYPEC_PORT_DRP)
		return priv->ops->set_mode(priv, TUSB320_MODE_DRP);
	else
		return priv->ops->set_mode(priv, TUSB320_MODE_PORT);
}

static const struct typec_operations tusb320_typec_ops = {
	.port_type_set	= tusb320_port_type_set,
};

static void tusb320_extcon_irq_handler(struct tusb320_priv *priv, u8 reg)
{
	int state, polarity;

	state = (reg >> TUSB320_REG9_ATTACHED_STATE_SHIFT) &
		TUSB320_REG9_ATTACHED_STATE_MASK;
	polarity = !!(reg & TUSB320_REG9_CABLE_DIRECTION);

	dev_dbg(priv->dev, "attached state: %s, polarity: %d\n",
		tusb_attached_states[state], polarity);

	extcon_set_state(priv->edev, EXTCON_USB,
			 state == TUSB320_ATTACHED_STATE_UFP);
	extcon_set_state(priv->edev, EXTCON_USB_HOST,
			 state == TUSB320_ATTACHED_STATE_DFP);
	extcon_set_property(priv->edev, EXTCON_USB,
			    EXTCON_PROP_USB_TYPEC_POLARITY,
			    (union extcon_property_value)polarity);
	extcon_set_property(priv->edev, EXTCON_USB_HOST,
			    EXTCON_PROP_USB_TYPEC_POLARITY,
			    (union extcon_property_value)polarity);
	extcon_sync(priv->edev, EXTCON_USB);
	extcon_sync(priv->edev, EXTCON_USB_HOST);

	priv->state = state;
}

static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
{
	struct typec_port *port = priv->port;
	struct device *dev = priv->dev;
	u8 mode, role, state;
	int ret, reg8;
	bool ori;

	ori = reg9 & TUSB320_REG9_CABLE_DIRECTION;
	typec_set_orientation(port, ori ? TYPEC_ORIENTATION_REVERSE :
					  TYPEC_ORIENTATION_NORMAL);

	state = (reg9 >> TUSB320_REG9_ATTACHED_STATE_SHIFT) &
		TUSB320_REG9_ATTACHED_STATE_MASK;
	if (state == TUSB320_ATTACHED_STATE_DFP)
		role = TYPEC_SOURCE;
	else
		role = TYPEC_SINK;

	typec_set_vconn_role(port, role);
	typec_set_pwr_role(port, role);
	typec_set_data_role(port, role == TYPEC_SOURCE ?
				  TYPEC_HOST : TYPEC_DEVICE);

	ret = regmap_read(priv->regmap, TUSB320_REG8, &reg8);
	if (ret) {
		dev_err(dev, "error during reg8 i2c read, ret=%d!\n", ret);
		return;
	}

	mode = FIELD_GET(TUSB320_REG8_CURRENT_MODE_DETECT, reg8);
	if (mode == TUSB320_REG8_CURRENT_MODE_DETECT_DEF)
		typec_set_pwr_opmode(port, TYPEC_PWR_MODE_USB);
	else if (mode == TUSB320_REG8_CURRENT_MODE_DETECT_MED)
		typec_set_pwr_opmode(port, TYPEC_PWR_MODE_1_5A);
	else if (mode == TUSB320_REG8_CURRENT_MODE_DETECT_HI)
		typec_set_pwr_opmode(port, TYPEC_PWR_MODE_3_0A);
	else	/* Charge through accessory */
		typec_set_pwr_opmode(port, TYPEC_PWR_MODE_USB);
}

static irqreturn_t tusb320_state_update_handler(struct tusb320_priv *priv,
						bool force_update)
{
	unsigned int reg;

	if (regmap_read(priv->regmap, TUSB320_REG9, &reg)) {
		dev_err(priv->dev, "error during i2c read!\n");
		return IRQ_NONE;
	}

	if (!force_update && !(reg & TUSB320_REG9_INTERRUPT_STATUS))
		return IRQ_NONE;

	tusb320_extcon_irq_handler(priv, reg);

	/*
	 * Type-C support is optional. Only call the Type-C handler if a
	 * port had been registered previously.
	 */
	if (priv->port)
		tusb320_typec_irq_handler(priv, reg);

	regmap_write(priv->regmap, TUSB320_REG9, reg);

	return IRQ_HANDLED;
}

static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
{
	struct tusb320_priv *priv = dev_id;

	return tusb320_state_update_handler(priv, false);
}

static const struct regmap_config tusb320_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
};

static int tusb320_extcon_probe(struct tusb320_priv *priv)
{
	int ret;

	priv->edev = devm_extcon_dev_allocate(priv->dev, tusb320_extcon_cable);
	if (IS_ERR(priv->edev)) {
		dev_err(priv->dev, "failed to allocate extcon device\n");
		return PTR_ERR(priv->edev);
	}

	ret = devm_extcon_dev_register(priv->dev, priv->edev);
	if (ret < 0) {
		dev_err(priv->dev, "failed to register extcon device\n");
		return ret;
	}

	extcon_set_property_capability(priv->edev, EXTCON_USB,
				       EXTCON_PROP_USB_TYPEC_POLARITY);
	extcon_set_property_capability(priv->edev, EXTCON_USB_HOST,
				       EXTCON_PROP_USB_TYPEC_POLARITY);

	return 0;
}

static int tusb320_typec_probe(struct i2c_client *client,
			       struct tusb320_priv *priv)
{
	struct fwnode_handle *connector;
	const char *cap_str;
	int ret;

	/* The Type-C connector is optional, for backward compatibility. */
	connector = device_get_named_child_node(&client->dev, "connector");
	if (!connector)
		return 0;

	/* Type-C connector found. */
	ret = typec_get_fw_cap(&priv->cap, connector);
	if (ret)
		return ret;

	priv->port_type = priv->cap.type;

	/* This goes into register 0x8 field CURRENT_MODE_ADVERTISE */
	ret = fwnode_property_read_string(connector, "typec-power-opmode", &cap_str);
	if (ret)
		return ret;

	ret = typec_find_pwr_opmode(cap_str);
	if (ret < 0)
		return ret;
	if (ret == TYPEC_PWR_MODE_PD)
		return -EINVAL;

	priv->pwr_opmode = ret;

	/* Initialize the hardware with the devicetree settings. */
	ret = tusb320_set_adv_pwr_mode(priv);
	if (ret)
		return ret;

	priv->cap.revision		= USB_TYPEC_REV_1_1;
	priv->cap.accessory[0]		= TYPEC_ACCESSORY_AUDIO;
	priv->cap.accessory[1]		= TYPEC_ACCESSORY_DEBUG;
	priv->cap.orientation_aware	= true;
	priv->cap.driver_data		= priv;
	priv->cap.ops			= &tusb320_typec_ops;
	priv->cap.fwnode		= connector;

	priv->port = typec_register_port(&client->dev, &priv->cap);
	if (IS_ERR(priv->port))
		return PTR_ERR(priv->port);

	return 0;
}

static int tusb320_probe(struct i2c_client *client)
{
	struct tusb320_priv *priv;
	const void *match_data;
	unsigned int revision;
	int ret;

	priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;
	priv->dev = &client->dev;

	priv->regmap = devm_regmap_init_i2c(client, &tusb320_regmap_config);
	if (IS_ERR(priv->regmap))
		return PTR_ERR(priv->regmap);

	ret = tusb320_check_signature(priv);
	if (ret)
		return ret;

	match_data = device_get_match_data(&client->dev);
	if (!match_data)
		return -EINVAL;

	priv->ops = (struct tusb320_ops*)match_data;

	if (priv->ops->get_revision) {
		ret = priv->ops->get_revision(priv, &revision);
		if (ret)
			dev_warn(priv->dev,
				"failed to read revision register: %d\n", ret);
		else
			dev_info(priv->dev, "chip revision %d\n", revision);
	}

	ret = tusb320_extcon_probe(priv);
	if (ret)
		return ret;

	ret = tusb320_typec_probe(client, priv);
	if (ret)
		return ret;

	/* update initial state */
	tusb320_state_update_handler(priv, true);

	/* Reset chip to its default state */
	ret = tusb320_reset(priv);
	if (ret)
		dev_warn(priv->dev, "failed to reset chip: %d\n", ret);
	else
		/*
		 * State and polarity might change after a reset, so update
		 * them again and make sure the interrupt status bit is cleared.
		 */
		tusb320_state_update_handler(priv, true);

	ret = devm_request_threaded_irq(priv->dev, client->irq, NULL,
					tusb320_irq_handler,
					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
					client->name, priv);

	return ret;
}

static const struct of_device_id tusb320_extcon_dt_match[] = {
	{ .compatible = "ti,tusb320", .data = &tusb320_ops, },
	{ .compatible = "ti,tusb320l", .data = &tusb320l_ops, },
	{ }
};
MODULE_DEVICE_TABLE(of, tusb320_extcon_dt_match);

static struct i2c_driver tusb320_extcon_driver = {
	.probe_new	= tusb320_probe,
	.driver		= {
		.name	= "extcon-tusb320",
		.of_match_table = tusb320_extcon_dt_match,
	},
};

static int __init tusb320_init(void)
{
	return i2c_add_driver(&tusb320_extcon_driver);
}
subsys_initcall(tusb320_init);

static void __exit tusb320_exit(void)
{
	i2c_del_driver(&tusb320_extcon_driver);
}
module_exit(tusb320_exit);

MODULE_AUTHOR("Michael Auchter <michael.auchter@ni.com>");
MODULE_DESCRIPTION("TI TUSB320 extcon driver");
MODULE_LICENSE("GPL v2");