1 /*
2  * max8903_charger.c - Maxim 8903 USB/Adapter Charger Driver
3  *
4  * Copyright (C) 2011 Samsung Electronics
5  * MyungJoo Ham <myungjoo.ham@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  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  *
21  */
22 
23 #include <linux/gpio.h>
24 #include <linux/interrupt.h>
25 #include <linux/module.h>
26 #include <linux/slab.h>
27 #include <linux/power_supply.h>
28 #include <linux/platform_device.h>
29 #include <linux/power/max8903_charger.h>
30 
31 struct max8903_data {
32 	struct max8903_pdata pdata;
33 	struct device *dev;
34 	struct power_supply psy;
35 	bool fault;
36 	bool usb_in;
37 	bool ta_in;
38 };
39 
40 static enum power_supply_property max8903_charger_props[] = {
41 	POWER_SUPPLY_PROP_STATUS, /* Charger status output */
42 	POWER_SUPPLY_PROP_ONLINE, /* External power source */
43 	POWER_SUPPLY_PROP_HEALTH, /* Fault or OK */
44 };
45 
max8903_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)46 static int max8903_get_property(struct power_supply *psy,
47 		enum power_supply_property psp,
48 		union power_supply_propval *val)
49 {
50 	struct max8903_data *data = container_of(psy,
51 			struct max8903_data, psy);
52 
53 	switch (psp) {
54 	case POWER_SUPPLY_PROP_STATUS:
55 		val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
56 		if (data->pdata.chg) {
57 			if (gpio_get_value(data->pdata.chg) == 0)
58 				val->intval = POWER_SUPPLY_STATUS_CHARGING;
59 			else if (data->usb_in || data->ta_in)
60 				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
61 			else
62 				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
63 		}
64 		break;
65 	case POWER_SUPPLY_PROP_ONLINE:
66 		val->intval = 0;
67 		if (data->usb_in || data->ta_in)
68 			val->intval = 1;
69 		break;
70 	case POWER_SUPPLY_PROP_HEALTH:
71 		val->intval = POWER_SUPPLY_HEALTH_GOOD;
72 		if (data->fault)
73 			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
74 		break;
75 	default:
76 		return -EINVAL;
77 	}
78 	return 0;
79 }
80 
max8903_dcin(int irq,void * _data)81 static irqreturn_t max8903_dcin(int irq, void *_data)
82 {
83 	struct max8903_data *data = _data;
84 	struct max8903_pdata *pdata = &data->pdata;
85 	bool ta_in;
86 	enum power_supply_type old_type;
87 
88 	ta_in = gpio_get_value(pdata->dok) ? false : true;
89 
90 	if (ta_in == data->ta_in)
91 		return IRQ_HANDLED;
92 
93 	data->ta_in = ta_in;
94 
95 	/* Set Current-Limit-Mode 1:DC 0:USB */
96 	if (pdata->dcm)
97 		gpio_set_value(pdata->dcm, ta_in ? 1 : 0);
98 
99 	/* Charger Enable / Disable (cen is negated) */
100 	if (pdata->cen)
101 		gpio_set_value(pdata->cen, ta_in ? 0 :
102 				(data->usb_in ? 0 : 1));
103 
104 	dev_dbg(data->dev, "TA(DC-IN) Charger %s.\n", ta_in ?
105 			"Connected" : "Disconnected");
106 
107 	old_type = data->psy.type;
108 
109 	if (data->ta_in)
110 		data->psy.type = POWER_SUPPLY_TYPE_MAINS;
111 	else if (data->usb_in)
112 		data->psy.type = POWER_SUPPLY_TYPE_USB;
113 	else
114 		data->psy.type = POWER_SUPPLY_TYPE_BATTERY;
115 
116 	if (old_type != data->psy.type)
117 		power_supply_changed(&data->psy);
118 
119 	return IRQ_HANDLED;
120 }
121 
max8903_usbin(int irq,void * _data)122 static irqreturn_t max8903_usbin(int irq, void *_data)
123 {
124 	struct max8903_data *data = _data;
125 	struct max8903_pdata *pdata = &data->pdata;
126 	bool usb_in;
127 	enum power_supply_type old_type;
128 
129 	usb_in = gpio_get_value(pdata->uok) ? false : true;
130 
131 	if (usb_in == data->usb_in)
132 		return IRQ_HANDLED;
133 
134 	data->usb_in = usb_in;
135 
136 	/* Do not touch Current-Limit-Mode */
137 
138 	/* Charger Enable / Disable (cen is negated) */
139 	if (pdata->cen)
140 		gpio_set_value(pdata->cen, usb_in ? 0 :
141 				(data->ta_in ? 0 : 1));
142 
143 	dev_dbg(data->dev, "USB Charger %s.\n", usb_in ?
144 			"Connected" : "Disconnected");
145 
146 	old_type = data->psy.type;
147 
148 	if (data->ta_in)
149 		data->psy.type = POWER_SUPPLY_TYPE_MAINS;
150 	else if (data->usb_in)
151 		data->psy.type = POWER_SUPPLY_TYPE_USB;
152 	else
153 		data->psy.type = POWER_SUPPLY_TYPE_BATTERY;
154 
155 	if (old_type != data->psy.type)
156 		power_supply_changed(&data->psy);
157 
158 	return IRQ_HANDLED;
159 }
160 
max8903_fault(int irq,void * _data)161 static irqreturn_t max8903_fault(int irq, void *_data)
162 {
163 	struct max8903_data *data = _data;
164 	struct max8903_pdata *pdata = &data->pdata;
165 	bool fault;
166 
167 	fault = gpio_get_value(pdata->flt) ? false : true;
168 
169 	if (fault == data->fault)
170 		return IRQ_HANDLED;
171 
172 	data->fault = fault;
173 
174 	if (fault)
175 		dev_err(data->dev, "Charger suffers a fault and stops.\n");
176 	else
177 		dev_err(data->dev, "Charger recovered from a fault.\n");
178 
179 	return IRQ_HANDLED;
180 }
181 
max8903_probe(struct platform_device * pdev)182 static __devinit int max8903_probe(struct platform_device *pdev)
183 {
184 	struct max8903_data *data;
185 	struct device *dev = &pdev->dev;
186 	struct max8903_pdata *pdata = pdev->dev.platform_data;
187 	int ret = 0;
188 	int gpio;
189 	int ta_in = 0;
190 	int usb_in = 0;
191 
192 	data = kzalloc(sizeof(struct max8903_data), GFP_KERNEL);
193 	if (data == NULL) {
194 		dev_err(dev, "Cannot allocate memory.\n");
195 		return -ENOMEM;
196 	}
197 	memcpy(&data->pdata, pdata, sizeof(struct max8903_pdata));
198 	data->dev = dev;
199 	platform_set_drvdata(pdev, data);
200 
201 	if (pdata->dc_valid == false && pdata->usb_valid == false) {
202 		dev_err(dev, "No valid power sources.\n");
203 		ret = -EINVAL;
204 		goto err;
205 	}
206 
207 	if (pdata->dc_valid) {
208 		if (pdata->dok && gpio_is_valid(pdata->dok) &&
209 				pdata->dcm && gpio_is_valid(pdata->dcm)) {
210 			gpio = pdata->dok; /* PULL_UPed Interrupt */
211 			ta_in = gpio_get_value(gpio) ? 0 : 1;
212 
213 			gpio = pdata->dcm; /* Output */
214 			gpio_set_value(gpio, ta_in);
215 		} else {
216 			dev_err(dev, "When DC is wired, DOK and DCM should"
217 					" be wired as well.\n");
218 			ret = -EINVAL;
219 			goto err;
220 		}
221 	} else {
222 		if (pdata->dcm) {
223 			if (gpio_is_valid(pdata->dcm))
224 				gpio_set_value(pdata->dcm, 0);
225 			else {
226 				dev_err(dev, "Invalid pin: dcm.\n");
227 				ret = -EINVAL;
228 				goto err;
229 			}
230 		}
231 	}
232 
233 	if (pdata->usb_valid) {
234 		if (pdata->uok && gpio_is_valid(pdata->uok)) {
235 			gpio = pdata->uok;
236 			usb_in = gpio_get_value(gpio) ? 0 : 1;
237 		} else {
238 			dev_err(dev, "When USB is wired, UOK should be wired."
239 					"as well.\n");
240 			ret = -EINVAL;
241 			goto err;
242 		}
243 	}
244 
245 	if (pdata->cen) {
246 		if (gpio_is_valid(pdata->cen)) {
247 			gpio_set_value(pdata->cen, (ta_in || usb_in) ? 0 : 1);
248 		} else {
249 			dev_err(dev, "Invalid pin: cen.\n");
250 			ret = -EINVAL;
251 			goto err;
252 		}
253 	}
254 
255 	if (pdata->chg) {
256 		if (!gpio_is_valid(pdata->chg)) {
257 			dev_err(dev, "Invalid pin: chg.\n");
258 			ret = -EINVAL;
259 			goto err;
260 		}
261 	}
262 
263 	if (pdata->flt) {
264 		if (!gpio_is_valid(pdata->flt)) {
265 			dev_err(dev, "Invalid pin: flt.\n");
266 			ret = -EINVAL;
267 			goto err;
268 		}
269 	}
270 
271 	if (pdata->usus) {
272 		if (!gpio_is_valid(pdata->usus)) {
273 			dev_err(dev, "Invalid pin: usus.\n");
274 			ret = -EINVAL;
275 			goto err;
276 		}
277 	}
278 
279 	data->fault = false;
280 	data->ta_in = ta_in;
281 	data->usb_in = usb_in;
282 
283 	data->psy.name = "max8903_charger";
284 	data->psy.type = (ta_in) ? POWER_SUPPLY_TYPE_MAINS :
285 			((usb_in) ? POWER_SUPPLY_TYPE_USB :
286 			 POWER_SUPPLY_TYPE_BATTERY);
287 	data->psy.get_property = max8903_get_property;
288 	data->psy.properties = max8903_charger_props;
289 	data->psy.num_properties = ARRAY_SIZE(max8903_charger_props);
290 
291 	ret = power_supply_register(dev, &data->psy);
292 	if (ret) {
293 		dev_err(dev, "failed: power supply register.\n");
294 		goto err;
295 	}
296 
297 	if (pdata->dc_valid) {
298 		ret = request_threaded_irq(gpio_to_irq(pdata->dok),
299 				NULL, max8903_dcin,
300 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
301 				"MAX8903 DC IN", data);
302 		if (ret) {
303 			dev_err(dev, "Cannot request irq %d for DC (%d)\n",
304 					gpio_to_irq(pdata->dok), ret);
305 			goto err_psy;
306 		}
307 	}
308 
309 	if (pdata->usb_valid) {
310 		ret = request_threaded_irq(gpio_to_irq(pdata->uok),
311 				NULL, max8903_usbin,
312 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
313 				"MAX8903 USB IN", data);
314 		if (ret) {
315 			dev_err(dev, "Cannot request irq %d for USB (%d)\n",
316 					gpio_to_irq(pdata->uok), ret);
317 			goto err_dc_irq;
318 		}
319 	}
320 
321 	if (pdata->flt) {
322 		ret = request_threaded_irq(gpio_to_irq(pdata->flt),
323 				NULL, max8903_fault,
324 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
325 				"MAX8903 Fault", data);
326 		if (ret) {
327 			dev_err(dev, "Cannot request irq %d for Fault (%d)\n",
328 					gpio_to_irq(pdata->flt), ret);
329 			goto err_usb_irq;
330 		}
331 	}
332 
333 	return 0;
334 
335 err_usb_irq:
336 	if (pdata->usb_valid)
337 		free_irq(gpio_to_irq(pdata->uok), data);
338 err_dc_irq:
339 	if (pdata->dc_valid)
340 		free_irq(gpio_to_irq(pdata->dok), data);
341 err_psy:
342 	power_supply_unregister(&data->psy);
343 err:
344 	kfree(data);
345 	return ret;
346 }
347 
max8903_remove(struct platform_device * pdev)348 static __devexit int max8903_remove(struct platform_device *pdev)
349 {
350 	struct max8903_data *data = platform_get_drvdata(pdev);
351 
352 	if (data) {
353 		struct max8903_pdata *pdata = &data->pdata;
354 
355 		if (pdata->flt)
356 			free_irq(gpio_to_irq(pdata->flt), data);
357 		if (pdata->usb_valid)
358 			free_irq(gpio_to_irq(pdata->uok), data);
359 		if (pdata->dc_valid)
360 			free_irq(gpio_to_irq(pdata->dok), data);
361 		power_supply_unregister(&data->psy);
362 		kfree(data);
363 	}
364 
365 	return 0;
366 }
367 
368 static struct platform_driver max8903_driver = {
369 	.probe	= max8903_probe,
370 	.remove	= __devexit_p(max8903_remove),
371 	.driver = {
372 		.name	= "max8903-charger",
373 		.owner	= THIS_MODULE,
374 	},
375 };
376 
377 module_platform_driver(max8903_driver);
378 
379 MODULE_LICENSE("GPL");
380 MODULE_DESCRIPTION("MAX8903 Charger Driver");
381 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
382 MODULE_ALIAS("platform:max8903-charger");
383