aboutsummaryrefslogtreecommitdiff
path: root/drivers/power/isp1704_charger.c
blob: 1bb3a91b1acc2eb376d6460006218a7b1f4e1e76 (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
/*
 * ISP1704 USB Charger Detection driver
 *
 * Copyright (C) 2010 Nokia Corporation
 * Copyright (C) 2012 - 2013 Pali Rohár <pali.rohar@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/delay.h>

#include <linux/usb/otg.h>
#include <linux/usb/ulpi.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/power/isp1704_charger.h>

/* Vendor specific Power Control register */
#define ISP1704_PWR_CTRL		0x3d
#define ISP1704_PWR_CTRL_SWCTRL		(1 << 0)
#define ISP1704_PWR_CTRL_DET_COMP	(1 << 1)
#define ISP1704_PWR_CTRL_BVALID_RISE	(1 << 2)
#define ISP1704_PWR_CTRL_BVALID_FALL	(1 << 3)
#define ISP1704_PWR_CTRL_DP_WKPU_EN	(1 << 4)
#define ISP1704_PWR_CTRL_VDAT_DET	(1 << 5)
#define ISP1704_PWR_CTRL_DPVSRC_EN	(1 << 6)
#define ISP1704_PWR_CTRL_HWDETECT	(1 << 7)

#define NXP_VENDOR_ID			0x04cc

static u16 isp170x_id[] = {
	0x1704,
	0x1707,
};

struct isp1704_charger {
	struct device		*dev;
	struct power_supply	psy;
	struct usb_phy		*phy;
	struct notifier_block	nb;
	struct work_struct	work;

	/* properties */
	char			model[8];
	unsigned		present:1;
	unsigned		online:1;
	unsigned		current_max;
};

static inline int isp1704_read(struct isp1704_charger *isp, u32 reg)
{
	return usb_phy_io_read(isp->phy, reg);
}

static inline int isp1704_write(struct isp1704_charger *isp, u32 val, u32 reg)
{
	return usb_phy_io_write(isp->phy, val, reg);
}

/*
 * Disable/enable the power from the isp1704 if a function for it
 * has been provided with platform data.
 */
static void isp1704_charger_set_power(struct isp1704_charger *isp, bool on)
{
	struct isp1704_charger_data	*board = isp->dev->platform_data;

	if (board && board->set_power)
		board->set_power(on);
}

/*
 * Determine is the charging port DCP (dedicated charger) or CDP (Host/HUB
 * chargers).
 *
 * REVISIT: The method is defined in Battery Charging Specification and is
 * applicable to any ULPI transceiver. Nothing isp170x specific here.
 */
static inline int isp1704_charger_type(struct isp1704_charger *isp)
{
	u8 reg;
	u8 func_ctrl;
	u8 otg_ctrl;
	int type = POWER_SUPPLY_TYPE_USB_DCP;

	func_ctrl = isp1704_read(isp, ULPI_FUNC_CTRL);
	otg_ctrl = isp1704_read(isp, ULPI_OTG_CTRL);

	/* disable pulldowns */
	reg = ULPI_OTG_CTRL_DM_PULLDOWN | ULPI_OTG_CTRL_DP_PULLDOWN;
	isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), reg);

	/* full speed */
	isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
			ULPI_FUNC_CTRL_XCVRSEL_MASK);
	isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL),
			ULPI_FUNC_CTRL_FULL_SPEED);

	/* Enable strong pull-up on DP (1.5K) and reset */
	reg = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
	isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), reg);
	usleep_range(1000, 2000);

	reg = isp1704_read(isp, ULPI_DEBUG);
	if ((reg & 3) != 3)
		type = POWER_SUPPLY_TYPE_USB_CDP;

	/* recover original state */
	isp1704_write(isp, ULPI_FUNC_CTRL, func_ctrl);
	isp1704_write(isp, ULPI_OTG_CTRL, otg_ctrl);

	return type;
}

/*
 * ISP1704 detects PS/2 adapters as charger. To make sure the detected charger
 * is actually a dedicated charger, the following steps need to be taken.
 */
static inline int isp1704_charger_verify(struct isp1704_charger *isp)
{
	int	ret = 0;
	u8	r;

	/* Reset the transceiver */
	r = isp1704_read(isp, ULPI_FUNC_CTRL);
	r |= ULPI_FUNC_CTRL_RESET;
	isp1704_write(isp, ULPI_FUNC_CTRL, r);
	usleep_range(1000, 2000);

	/* Set normal mode */
	r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK);
	isp1704_write(isp, ULPI_FUNC_CTRL, r);

	/* Clear the DP and DM pull-down bits */
	r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN;
	isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), r);

	/* Enable strong pull-up on DP (1.5K) and reset */
	r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
	isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), r);
	usleep_range(1000, 2000);

	/* Read the line state */
	if (!isp1704_read(isp, ULPI_DEBUG)) {
		/* Disable strong pull-up on DP (1.5K) */
		isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
				ULPI_FUNC_CTRL_TERMSELECT);
		return 1;
	}

	/* Is it a charger or PS/2 connection */

	/* Enable weak pull-up resistor on DP */
	isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
			ISP1704_PWR_CTRL_DP_WKPU_EN);

	/* Disable strong pull-up on DP (1.5K) */
	isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
			ULPI_FUNC_CTRL_TERMSELECT);

	/* Enable weak pull-down resistor on DM */
	isp1704_write(isp, ULPI_SET(ULPI_OTG_CTRL),
			ULPI_OTG_CTRL_DM_PULLDOWN);

	/* It's a charger if the line states are clear */
	if (!(isp1704_read(isp, ULPI_DEBUG)))
		ret = 1;

	/* Disable weak pull-up resistor on DP */
	isp1704_write(isp, ULPI_CLR(ISP1704_PWR_CTRL),
			ISP1704_PWR_CTRL_DP_WKPU_EN);

	return ret;
}

static inline int isp1704_charger_detect(struct isp1704_charger *isp)
{
	unsigned long	timeout;
	u8		pwr_ctrl;
	int		ret = 0;

	pwr_ctrl = isp1704_read(isp, ISP1704_PWR_CTRL);

	/* set SW control bit in PWR_CTRL register */
	isp1704_write(isp, ISP1704_PWR_CTRL,
			ISP1704_PWR_CTRL_SWCTRL);

	/* enable manual charger detection */
	isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
			ISP1704_PWR_CTRL_SWCTRL
			| ISP1704_PWR_CTRL_DPVSRC_EN);
	usleep_range(1000, 2000);

	timeout = jiffies + msecs_to_jiffies(300);
	do {
		/* Check if there is a charger */
		if (isp1704_read(isp, ISP1704_PWR_CTRL)
				& ISP1704_PWR_CTRL_VDAT_DET) {
			ret = isp1704_charger_verify(isp);
			break;
		}
	} while (!time_after(jiffies, timeout) && isp->online);

	/* recover original state */
	isp1704_write(isp, ISP1704_PWR_CTRL, pwr_ctrl);

	return ret;
}

static inline int isp1704_charger_detect_dcp(struct isp1704_charger *isp)
{
	if (isp1704_charger_detect(isp) &&
			isp1704_charger_type(isp) == POWER_SUPPLY_TYPE_USB_DCP)
		return true;
	else
		return false;
}

static void isp1704_charger_work(struct work_struct *data)
{
	struct isp1704_charger	*isp =
		container_of(data, struct isp1704_charger, work);
	static DEFINE_MUTEX(lock);

	mutex_lock(&lock);

	switch (isp->phy->last_event) {
	case USB_EVENT_VBUS:
		/* do not call wall charger detection more times */
		if (!isp->present) {
			isp->online = true;
			isp->present = 1;
			isp1704_charger_set_power(isp, 1);

			/* detect wall charger */
			if (isp1704_charger_detect_dcp(isp)) {
				isp->psy.type = POWER_SUPPLY_TYPE_USB_DCP;
				isp->current_max = 1800;
			} else {
				isp->psy.type = POWER_SUPPLY_TYPE_USB;
				isp->current_max = 500;
			}

			/* enable data pullups */
			if (isp->phy->otg->gadget)
				usb_gadget_connect(isp->phy->otg->gadget);
		}

		if (isp->psy.type != POWER_SUPPLY_TYPE_USB_DCP) {
			/*
			 * Only 500mA here or high speed chirp
			 * handshaking may break
			 */
			if (isp->current_max > 500)
				isp->current_max = 500;

			if (isp->current_max > 100)
				isp->psy.type = POWER_SUPPLY_TYPE_USB_CDP;
		}
		break;
	case USB_EVENT_NONE:
		isp->online = false;
		isp->present = 0;
		isp->current_max = 0;
		isp->psy.type = POWER_SUPPLY_TYPE_USB;

		/*
		 * Disable data pullups. We need to prevent the controller from
		 * enumerating.
		 *
		 * FIXME: This is here to allow charger detection with Host/HUB
		 * chargers. The pullups may be enabled elsewhere, so this can
		 * not be the final solution.
		 */
		if (isp->phy->otg->gadget)
			usb_gadget_disconnect(isp->phy->otg->gadget);

		isp1704_charger_set_power(isp, 0);
		break;
	default:
		goto out;
	}

	power_supply_changed(&isp->psy);
out:
	mutex_unlock(&lock);
}

static int isp1704_notifier_call(struct notifier_block *nb,
		unsigned long val, void *v)
{
	struct isp1704_charger *isp =
		container_of(nb, struct isp1704_charger, nb);

	schedule_work(&isp->work);

	return NOTIFY_OK;
}

static int isp1704_charger_get_property(struct power_supply *psy,
				enum power_supply_property psp,
				union power_supply_propval *val)
{
	struct isp1704_charger *isp =
		container_of(psy, struct isp1704_charger, psy);

	switch (psp) {
	case POWER_SUPPLY_PROP_PRESENT:
		val->intval = isp->present;
		break;
	case POWER_SUPPLY_PROP_ONLINE:
		val->intval = isp->online;
		break;
	case POWER_SUPPLY_PROP_CURRENT_MAX:
		val->intval = isp->current_max;
		break;
	case POWER_SUPPLY_PROP_MODEL_NAME:
		val->strval = isp->model;
		break;
	case POWER_SUPPLY_PROP_MANUFACTURER:
		val->strval = "NXP";
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static enum power_supply_property power_props[] = {
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_ONLINE,
	POWER_SUPPLY_PROP_CURRENT_MAX,
	POWER_SUPPLY_PROP_MODEL_NAME,
	POWER_SUPPLY_PROP_MANUFACTURER,
};

static inline int isp1704_test_ulpi(struct isp1704_charger *isp)
{
	int vendor;
	int product;
	int i;
	int ret = -ENODEV;

	/* Test ULPI interface */
	ret = isp1704_write(isp, ULPI_SCRATCH, 0xaa);
	if (ret < 0)
		return ret;

	ret = isp1704_read(isp, ULPI_SCRATCH);
	if (ret < 0)
		return ret;

	if (ret != 0xaa)
		return -ENODEV;

	/* Verify the product and vendor id matches */
	vendor = isp1704_read(isp, ULPI_VENDOR_ID_LOW);
	vendor |= isp1704_read(isp, ULPI_VENDOR_ID_HIGH) << 8;
	if (vendor != NXP_VENDOR_ID)
		return -ENODEV;

	product = isp1704_read(isp, ULPI_PRODUCT_ID_LOW);
	product |= isp1704_read(isp, ULPI_PRODUCT_ID_HIGH) << 8;

	for (i = 0; i < ARRAY_SIZE(isp170x_id); i++) {
		if (product == isp170x_id[i]) {
			sprintf(isp->model, "isp%x", product);
			return product;
		}
	}

	dev_err(isp->dev, "product id %x not matching known ids", product);

	return -ENODEV;
}

static int isp1704_charger_probe(struct platform_device *pdev)
{
	struct isp1704_charger	*isp;
	int			ret = -ENODEV;

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

	isp->phy = usb_get_phy(USB_PHY_TYPE_USB2);
	if (IS_ERR_OR_NULL(isp->phy))
		goto fail0;

	isp->dev = &pdev->dev;
	platform_set_drvdata(pdev, isp);

	isp1704_charger_set_power(isp, 1);

	ret = isp1704_test_ulpi(isp);
	if (ret < 0)
		goto fail1;

	isp->psy.name		= "isp1704";
	isp->psy.type		= POWER_SUPPLY_TYPE_USB;
	isp->psy.properties	= power_props;
	isp->psy.num_properties	= ARRAY_SIZE(power_props);
	isp->psy.get_property	= isp1704_charger_get_property;

	ret = power_supply_register(isp->dev, &isp->psy);
	if (ret)
		goto fail1;

	/*
	 * REVISIT: using work in order to allow the usb notifications to be
	 * made atomically in the future.
	 */
	INIT_WORK(&isp->work, isp1704_charger_work);

	isp->nb.notifier_call = isp1704_notifier_call;

	ret = usb_register_notifier(isp->phy, &isp->nb);
	if (ret)
		goto fail2;

	dev_info(isp->dev, "registered with product id %s\n", isp->model);

	/*
	 * Taking over the D+ pullup.
	 *
	 * FIXME: The device will be disconnected if it was already
	 * enumerated. The charger driver should be always loaded before any
	 * gadget is loaded.
	 */
	if (isp->phy->otg->gadget)
		usb_gadget_disconnect(isp->phy->otg->gadget);

	if (isp->phy->last_event == USB_EVENT_NONE)
		isp1704_charger_set_power(isp, 0);

	/* Detect charger if VBUS is valid (the cable was already plugged). */
	if (isp->phy->last_event == USB_EVENT_VBUS &&
			!isp->phy->otg->default_a)
		schedule_work(&isp->work);

	return 0;
fail2:
	power_supply_unregister(&isp->psy);
fail1:
	isp1704_charger_set_power(isp, 0);
	usb_put_phy(isp->phy);
fail0:
	dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret);

	return ret;
}

static int isp1704_charger_remove(struct platform_device *pdev)
{
	struct isp1704_charger *isp = platform_get_drvdata(pdev);

	usb_unregister_notifier(isp->phy, &isp->nb);
	power_supply_unregister(&isp->psy);
	usb_put_phy(isp->phy);
	isp1704_charger_set_power(isp, 0);

	return 0;
}

static struct platform_driver isp1704_charger_driver = {
	.driver = {
		.name = "isp1704_charger",
	},
	.probe = isp1704_charger_probe,
	.remove = isp1704_charger_remove,
};

module_platform_driver(isp1704_charger_driver);

MODULE_ALIAS("platform:isp1704_charger");
MODULE_AUTHOR("Nokia Corporation");
MODULE_DESCRIPTION("ISP170x USB Charger driver");
MODULE_LICENSE("GPL");