1 /*
2  * extcon-max8997.c - MAX8997 extcon driver to support MAX8997 MUIC
3  *
4  *  Copyright (C) 2012 Samsung Electronics
5  *  Donggeun Kim <dg77.kim@samsung.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/i2c.h>
21 #include <linux/slab.h>
22 #include <linux/interrupt.h>
23 #include <linux/err.h>
24 #include <linux/platform_device.h>
25 #include <linux/kobject.h>
26 #include <linux/mfd/max8997.h>
27 #include <linux/mfd/max8997-private.h>
28 #include <linux/extcon.h>
29 #include <linux/irqdomain.h>
30 
31 #define	DEV_NAME			"max8997-muic"
32 
33 /* MAX8997-MUIC STATUS1 register */
34 #define STATUS1_ADC_SHIFT		0
35 #define STATUS1_ADCLOW_SHIFT		5
36 #define STATUS1_ADCERR_SHIFT		6
37 #define STATUS1_ADC_MASK		(0x1f << STATUS1_ADC_SHIFT)
38 #define STATUS1_ADCLOW_MASK		(0x1 << STATUS1_ADCLOW_SHIFT)
39 #define STATUS1_ADCERR_MASK		(0x1 << STATUS1_ADCERR_SHIFT)
40 
41 /* MAX8997-MUIC STATUS2 register */
42 #define STATUS2_CHGTYP_SHIFT		0
43 #define STATUS2_CHGDETRUN_SHIFT		3
44 #define STATUS2_DCDTMR_SHIFT		4
45 #define STATUS2_DBCHG_SHIFT		5
46 #define STATUS2_VBVOLT_SHIFT		6
47 #define STATUS2_CHGTYP_MASK		(0x7 << STATUS2_CHGTYP_SHIFT)
48 #define STATUS2_CHGDETRUN_MASK		(0x1 << STATUS2_CHGDETRUN_SHIFT)
49 #define STATUS2_DCDTMR_MASK		(0x1 << STATUS2_DCDTMR_SHIFT)
50 #define STATUS2_DBCHG_MASK		(0x1 << STATUS2_DBCHG_SHIFT)
51 #define STATUS2_VBVOLT_MASK		(0x1 << STATUS2_VBVOLT_SHIFT)
52 
53 /* MAX8997-MUIC STATUS3 register */
54 #define STATUS3_OVP_SHIFT		2
55 #define STATUS3_OVP_MASK		(0x1 << STATUS3_OVP_SHIFT)
56 
57 /* MAX8997-MUIC CONTROL1 register */
58 #define COMN1SW_SHIFT			0
59 #define COMP2SW_SHIFT			3
60 #define COMN1SW_MASK			(0x7 << COMN1SW_SHIFT)
61 #define COMP2SW_MASK			(0x7 << COMP2SW_SHIFT)
62 #define SW_MASK				(COMP2SW_MASK | COMN1SW_MASK)
63 
64 #define MAX8997_SW_USB		((1 << COMP2SW_SHIFT) | (1 << COMN1SW_SHIFT))
65 #define MAX8997_SW_AUDIO	((2 << COMP2SW_SHIFT) | (2 << COMN1SW_SHIFT))
66 #define MAX8997_SW_UART		((3 << COMP2SW_SHIFT) | (3 << COMN1SW_SHIFT))
67 #define MAX8997_SW_OPEN		((0 << COMP2SW_SHIFT) | (0 << COMN1SW_SHIFT))
68 
69 #define	MAX8997_ADC_GROUND		0x00
70 #define	MAX8997_ADC_MHL			0x01
71 #define	MAX8997_ADC_JIG_USB_1		0x18
72 #define	MAX8997_ADC_JIG_USB_2		0x19
73 #define	MAX8997_ADC_DESKDOCK		0x1a
74 #define	MAX8997_ADC_JIG_UART		0x1c
75 #define	MAX8997_ADC_CARDOCK		0x1d
76 #define	MAX8997_ADC_OPEN		0x1f
77 
78 struct max8997_muic_irq {
79 	unsigned int irq;
80 	const char *name;
81 	unsigned int virq;
82 };
83 
84 static struct max8997_muic_irq muic_irqs[] = {
85 	{ MAX8997_MUICIRQ_ADCError, "muic-ADC_error" },
86 	{ MAX8997_MUICIRQ_ADCLow, "muic-ADC_low" },
87 	{ MAX8997_MUICIRQ_ADC, "muic-ADC" },
88 	{ MAX8997_MUICIRQ_VBVolt, "muic-VB_voltage" },
89 	{ MAX8997_MUICIRQ_DBChg, "muic-DB_charger" },
90 	{ MAX8997_MUICIRQ_DCDTmr, "muic-DCD_timer" },
91 	{ MAX8997_MUICIRQ_ChgDetRun, "muic-CDR_status" },
92 	{ MAX8997_MUICIRQ_ChgTyp, "muic-charger_type" },
93 	{ MAX8997_MUICIRQ_OVP, "muic-over_voltage" },
94 };
95 
96 struct max8997_muic_info {
97 	struct device *dev;
98 	struct i2c_client *muic;
99 	struct max8997_muic_platform_data *muic_pdata;
100 
101 	int irq;
102 	struct work_struct irq_work;
103 
104 	enum max8997_muic_charger_type pre_charger_type;
105 	int pre_adc;
106 
107 	struct mutex mutex;
108 
109 	struct extcon_dev	*edev;
110 };
111 
112 const char *max8997_extcon_cable[] = {
113 	[0] = "USB",
114 	[1] = "USB-Host",
115 	[2] = "TA",
116 	[3] = "Fast-charger",
117 	[4] = "Slow-charger",
118 	[5] = "Charge-downstream",
119 	[6] = "MHL",
120 	[7] = "Dock-desk",
121 	[8] = "Dock-card",
122 	[9] = "JIG",
123 
124 	NULL,
125 };
126 
127 static int max8997_muic_handle_usb(struct max8997_muic_info *info,
128 			enum max8997_muic_usb_type usb_type, bool attached)
129 {
130 	int ret = 0;
131 
132 	if (usb_type == MAX8997_USB_HOST) {
133 		/* switch to USB */
134 		ret = max8997_update_reg(info->muic, MAX8997_MUIC_REG_CONTROL1,
135 				attached ? MAX8997_SW_USB : MAX8997_SW_OPEN,
136 				SW_MASK);
137 		if (ret) {
138 			dev_err(info->dev, "failed to update muic register\n");
139 			goto out;
140 		}
141 	}
142 
143 	switch (usb_type) {
144 	case MAX8997_USB_HOST:
145 		extcon_set_cable_state(info->edev, "USB-Host", attached);
146 		break;
147 	case MAX8997_USB_DEVICE:
148 		extcon_set_cable_state(info->edev, "USB", attached);
149 		break;
150 	default:
151 		ret = -EINVAL;
152 		break;
153 	}
154 
155 out:
156 	return ret;
157 }
158 
159 static int max8997_muic_handle_dock(struct max8997_muic_info *info,
160 			int adc, bool attached)
161 {
162 	int ret = 0;
163 
164 	/* switch to AUDIO */
165 	ret = max8997_update_reg(info->muic, MAX8997_MUIC_REG_CONTROL1,
166 				attached ? MAX8997_SW_AUDIO : MAX8997_SW_OPEN,
167 				SW_MASK);
168 	if (ret) {
169 		dev_err(info->dev, "failed to update muic register\n");
170 		goto out;
171 	}
172 
173 	switch (adc) {
174 	case MAX8997_ADC_DESKDOCK:
175 		extcon_set_cable_state(info->edev, "Dock-desk", attached);
176 		break;
177 	case MAX8997_ADC_CARDOCK:
178 		extcon_set_cable_state(info->edev, "Dock-card", attached);
179 		break;
180 	default:
181 		ret = -EINVAL;
182 		break;
183 	}
184 out:
185 	return ret;
186 }
187 
188 static int max8997_muic_handle_jig_uart(struct max8997_muic_info *info,
189 			bool attached)
190 {
191 	int ret = 0;
192 
193 	/* switch to UART */
194 	ret = max8997_update_reg(info->muic, MAX8997_MUIC_REG_CONTROL1,
195 				attached ? MAX8997_SW_UART : MAX8997_SW_OPEN,
196 				SW_MASK);
197 	if (ret) {
198 		dev_err(info->dev, "failed to update muic register\n");
199 		goto out;
200 	}
201 
202 	extcon_set_cable_state(info->edev, "JIG", attached);
203 out:
204 	return ret;
205 }
206 
207 static int max8997_muic_handle_adc_detach(struct max8997_muic_info *info)
208 {
209 	int ret = 0;
210 
211 	switch (info->pre_adc) {
212 	case MAX8997_ADC_GROUND:
213 		ret = max8997_muic_handle_usb(info, MAX8997_USB_HOST, false);
214 		break;
215 	case MAX8997_ADC_MHL:
216 		extcon_set_cable_state(info->edev, "MHL", false);
217 		break;
218 	case MAX8997_ADC_JIG_USB_1:
219 	case MAX8997_ADC_JIG_USB_2:
220 		ret = max8997_muic_handle_usb(info, MAX8997_USB_DEVICE, false);
221 		break;
222 	case MAX8997_ADC_DESKDOCK:
223 	case MAX8997_ADC_CARDOCK:
224 		ret = max8997_muic_handle_dock(info, info->pre_adc, false);
225 		break;
226 	case MAX8997_ADC_JIG_UART:
227 		ret = max8997_muic_handle_jig_uart(info, false);
228 		break;
229 	default:
230 		break;
231 	}
232 
233 	return ret;
234 }
235 
236 static int max8997_muic_handle_adc(struct max8997_muic_info *info, int adc)
237 {
238 	int ret = 0;
239 
240 	switch (adc) {
241 	case MAX8997_ADC_GROUND:
242 		ret = max8997_muic_handle_usb(info, MAX8997_USB_HOST, true);
243 		break;
244 	case MAX8997_ADC_MHL:
245 		extcon_set_cable_state(info->edev, "MHL", true);
246 		break;
247 	case MAX8997_ADC_JIG_USB_1:
248 	case MAX8997_ADC_JIG_USB_2:
249 		ret = max8997_muic_handle_usb(info, MAX8997_USB_DEVICE, true);
250 		break;
251 	case MAX8997_ADC_DESKDOCK:
252 	case MAX8997_ADC_CARDOCK:
253 		ret = max8997_muic_handle_dock(info, adc, true);
254 		break;
255 	case MAX8997_ADC_JIG_UART:
256 		ret = max8997_muic_handle_jig_uart(info, true);
257 		break;
258 	case MAX8997_ADC_OPEN:
259 		ret = max8997_muic_handle_adc_detach(info);
260 		break;
261 	default:
262 		ret = -EINVAL;
263 		goto out;
264 	}
265 
266 	info->pre_adc = adc;
267 out:
268 	return ret;
269 }
270 
271 static int max8997_muic_handle_charger_type_detach(
272 				struct max8997_muic_info *info)
273 {
274 	switch (info->pre_charger_type) {
275 	case MAX8997_CHARGER_TYPE_USB:
276 		extcon_set_cable_state(info->edev, "USB", false);
277 		break;
278 	case MAX8997_CHARGER_TYPE_DOWNSTREAM_PORT:
279 		extcon_set_cable_state(info->edev, "Charge-downstream", false);
280 		break;
281 	case MAX8997_CHARGER_TYPE_DEDICATED_CHG:
282 		extcon_set_cable_state(info->edev, "TA", false);
283 		break;
284 	case MAX8997_CHARGER_TYPE_500MA:
285 		extcon_set_cable_state(info->edev, "Slow-charger", false);
286 		break;
287 	case MAX8997_CHARGER_TYPE_1A:
288 		extcon_set_cable_state(info->edev, "Fast-charger", false);
289 		break;
290 	default:
291 		return -EINVAL;
292 		break;
293 	}
294 
295 	return 0;
296 }
297 
298 static int max8997_muic_handle_charger_type(struct max8997_muic_info *info,
299 				enum max8997_muic_charger_type charger_type)
300 {
301 	u8 adc;
302 	int ret;
303 
304 	ret = max8997_read_reg(info->muic, MAX8997_MUIC_REG_STATUS1, &adc);
305 	if (ret) {
306 		dev_err(info->dev, "failed to read muic register\n");
307 		goto out;
308 	}
309 
310 	switch (charger_type) {
311 	case MAX8997_CHARGER_TYPE_NONE:
312 		ret = max8997_muic_handle_charger_type_detach(info);
313 		break;
314 	case MAX8997_CHARGER_TYPE_USB:
315 		if ((adc & STATUS1_ADC_MASK) == MAX8997_ADC_OPEN) {
316 			max8997_muic_handle_usb(info,
317 					MAX8997_USB_DEVICE, true);
318 		}
319 		break;
320 	case MAX8997_CHARGER_TYPE_DOWNSTREAM_PORT:
321 		extcon_set_cable_state(info->edev, "Charge-downstream", true);
322 		break;
323 	case MAX8997_CHARGER_TYPE_DEDICATED_CHG:
324 		extcon_set_cable_state(info->edev, "TA", true);
325 		break;
326 	case MAX8997_CHARGER_TYPE_500MA:
327 		extcon_set_cable_state(info->edev, "Slow-charger", true);
328 		break;
329 	case MAX8997_CHARGER_TYPE_1A:
330 		extcon_set_cable_state(info->edev, "Fast-charger", true);
331 		break;
332 	default:
333 		ret = -EINVAL;
334 		goto out;
335 	}
336 
337 	info->pre_charger_type = charger_type;
338 out:
339 	return ret;
340 }
341 
342 static void max8997_muic_irq_work(struct work_struct *work)
343 {
344 	struct max8997_muic_info *info = container_of(work,
345 			struct max8997_muic_info, irq_work);
346 	u8 status[2];
347 	u8 adc, chg_type;
348 	int irq_type = 0;
349 	int i, ret;
350 
351 	mutex_lock(&info->mutex);
352 
353 	ret = max8997_bulk_read(info->muic, MAX8997_MUIC_REG_STATUS1,
354 				2, status);
355 	if (ret) {
356 		dev_err(info->dev, "failed to read muic register\n");
357 		mutex_unlock(&info->mutex);
358 		return;
359 	}
360 
361 	dev_dbg(info->dev, "%s: STATUS1:0x%x, 2:0x%x\n", __func__,
362 			status[0], status[1]);
363 
364 	for (i = 0 ; i < ARRAY_SIZE(muic_irqs) ; i++)
365 		if (info->irq == muic_irqs[i].virq)
366 			irq_type = muic_irqs[i].irq;
367 
368 	switch (irq_type) {
369 	case MAX8997_MUICIRQ_ADC:
370 		adc = status[0] & STATUS1_ADC_MASK;
371 		adc >>= STATUS1_ADC_SHIFT;
372 
373 		max8997_muic_handle_adc(info, adc);
374 		break;
375 	case MAX8997_MUICIRQ_ChgTyp:
376 		chg_type = status[1] & STATUS2_CHGTYP_MASK;
377 		chg_type >>= STATUS2_CHGTYP_SHIFT;
378 
379 		max8997_muic_handle_charger_type(info, chg_type);
380 		break;
381 	default:
382 		dev_info(info->dev, "misc interrupt: irq %d occurred\n",
383 				irq_type);
384 		break;
385 	}
386 
387 	mutex_unlock(&info->mutex);
388 
389 	return;
390 }
391 
392 static irqreturn_t max8997_muic_irq_handler(int irq, void *data)
393 {
394 	struct max8997_muic_info *info = data;
395 
396 	dev_dbg(info->dev, "irq:%d\n", irq);
397 	info->irq = irq;
398 
399 	schedule_work(&info->irq_work);
400 
401 	return IRQ_HANDLED;
402 }
403 
404 static void max8997_muic_detect_dev(struct max8997_muic_info *info)
405 {
406 	int ret;
407 	u8 status[2], adc, chg_type;
408 
409 	ret = max8997_bulk_read(info->muic, MAX8997_MUIC_REG_STATUS1,
410 				2, status);
411 	if (ret) {
412 		dev_err(info->dev, "failed to read muic register\n");
413 		return;
414 	}
415 
416 	dev_info(info->dev, "STATUS1:0x%x, STATUS2:0x%x\n",
417 			status[0], status[1]);
418 
419 	adc = status[0] & STATUS1_ADC_MASK;
420 	adc >>= STATUS1_ADC_SHIFT;
421 
422 	chg_type = status[1] & STATUS2_CHGTYP_MASK;
423 	chg_type >>= STATUS2_CHGTYP_SHIFT;
424 
425 	max8997_muic_handle_adc(info, adc);
426 	max8997_muic_handle_charger_type(info, chg_type);
427 }
428 
429 static int max8997_muic_probe(struct platform_device *pdev)
430 {
431 	struct max8997_dev *max8997 = dev_get_drvdata(pdev->dev.parent);
432 	struct max8997_platform_data *pdata = dev_get_platdata(max8997->dev);
433 	struct max8997_muic_info *info;
434 	int ret, i;
435 
436 	info = devm_kzalloc(&pdev->dev, sizeof(struct max8997_muic_info),
437 			    GFP_KERNEL);
438 	if (!info) {
439 		dev_err(&pdev->dev, "failed to allocate memory\n");
440 		return -ENOMEM;
441 	}
442 
443 	info->dev = &pdev->dev;
444 	info->muic = max8997->muic;
445 
446 	platform_set_drvdata(pdev, info);
447 	mutex_init(&info->mutex);
448 
449 	INIT_WORK(&info->irq_work, max8997_muic_irq_work);
450 
451 	for (i = 0; i < ARRAY_SIZE(muic_irqs); i++) {
452 		struct max8997_muic_irq *muic_irq = &muic_irqs[i];
453 		unsigned int virq = 0;
454 
455 		virq = irq_create_mapping(max8997->irq_domain, muic_irq->irq);
456 		if (!virq) {
457 			ret = -EINVAL;
458 			goto err_irq;
459 		}
460 		muic_irq->virq = virq;
461 
462 		ret = request_threaded_irq(virq, NULL, max8997_muic_irq_handler,
463 				0, muic_irq->name, info);
464 		if (ret) {
465 			dev_err(&pdev->dev,
466 				"failed: irq request (IRQ: %d,"
467 				" error :%d)\n",
468 				muic_irq->irq, ret);
469 			goto err_irq;
470 		}
471 	}
472 
473 	/* External connector */
474 	info->edev = devm_kzalloc(&pdev->dev, sizeof(struct extcon_dev),
475 				  GFP_KERNEL);
476 	if (!info->edev) {
477 		dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
478 		ret = -ENOMEM;
479 		goto err_irq;
480 	}
481 	info->edev->name = DEV_NAME;
482 	info->edev->supported_cable = max8997_extcon_cable;
483 	ret = extcon_dev_register(info->edev, NULL);
484 	if (ret) {
485 		dev_err(&pdev->dev, "failed to register extcon device\n");
486 		goto err_irq;
487 	}
488 
489 	/* Initialize registers according to platform data */
490 	if (pdata->muic_pdata) {
491 		struct max8997_muic_platform_data *mdata = info->muic_pdata;
492 
493 		for (i = 0; i < mdata->num_init_data; i++) {
494 			max8997_write_reg(info->muic, mdata->init_data[i].addr,
495 					mdata->init_data[i].data);
496 		}
497 	}
498 
499 	/* Initial device detection */
500 	max8997_muic_detect_dev(info);
501 
502 	return ret;
503 
504 err_irq:
505 	while (--i >= 0)
506 		free_irq(muic_irqs[i].virq, info);
507 	return ret;
508 }
509 
510 static int max8997_muic_remove(struct platform_device *pdev)
511 {
512 	struct max8997_muic_info *info = platform_get_drvdata(pdev);
513 	int i;
514 
515 	for (i = 0; i < ARRAY_SIZE(muic_irqs); i++)
516 		free_irq(muic_irqs[i].virq, info);
517 	cancel_work_sync(&info->irq_work);
518 
519 	extcon_dev_unregister(info->edev);
520 
521 	return 0;
522 }
523 
524 static struct platform_driver max8997_muic_driver = {
525 	.driver		= {
526 		.name	= DEV_NAME,
527 		.owner	= THIS_MODULE,
528 	},
529 	.probe		= max8997_muic_probe,
530 	.remove		= max8997_muic_remove,
531 };
532 
533 module_platform_driver(max8997_muic_driver);
534 
535 MODULE_DESCRIPTION("Maxim MAX8997 Extcon driver");
536 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
537 MODULE_LICENSE("GPL");
538