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max8903_charger.c
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1 /*
2  * max8903_charger.c - Maxim 8903 USB/Adapter Charger Driver
3  *
4  * Copyright (C) 2011 Samsung Electronics
5  * MyungJoo Ham <[email protected]>
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 
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 
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 
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 
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 
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 
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 <[email protected]>");
382 MODULE_ALIAS("platform:max8903-charger");
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