Merge tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux...
[linux-2.6.git] / drivers / power / jz4740-battery.c
1 /*
2  * Battery measurement code for Ingenic JZ SOC.
3  *
4  * Copyright (C) 2009 Jiejing Zhang <kzjeef@gmail.com>
5  * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
6  *
7  * based on tosa_battery.c
8  *
9  * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>
10 *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  *
15  */
16
17 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/slab.h>
22 #include <linux/io.h>
23
24 #include <linux/delay.h>
25 #include <linux/gpio.h>
26 #include <linux/mfd/core.h>
27 #include <linux/power_supply.h>
28
29 #include <linux/power/jz4740-battery.h>
30 #include <linux/jz4740-adc.h>
31
32 struct jz_battery {
33         struct jz_battery_platform_data *pdata;
34         struct platform_device *pdev;
35
36         struct resource *mem;
37         void __iomem *base;
38
39         int irq;
40         int charge_irq;
41
42         const struct mfd_cell *cell;
43
44         int status;
45         long voltage;
46
47         struct completion read_completion;
48
49         struct power_supply battery;
50         struct delayed_work work;
51
52         struct mutex lock;
53 };
54
55 static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
56 {
57         return container_of(psy, struct jz_battery, battery);
58 }
59
60 static irqreturn_t jz_battery_irq_handler(int irq, void *devid)
61 {
62         struct jz_battery *battery = devid;
63
64         complete(&battery->read_completion);
65         return IRQ_HANDLED;
66 }
67
68 static long jz_battery_read_voltage(struct jz_battery *battery)
69 {
70         long t;
71         unsigned long val;
72         long voltage;
73
74         mutex_lock(&battery->lock);
75
76         INIT_COMPLETION(battery->read_completion);
77
78         enable_irq(battery->irq);
79         battery->cell->enable(battery->pdev);
80
81         t = wait_for_completion_interruptible_timeout(&battery->read_completion,
82                 HZ);
83
84         if (t > 0) {
85                 val = readw(battery->base) & 0xfff;
86
87                 if (battery->pdata->info.voltage_max_design <= 2500000)
88                         val = (val * 78125UL) >> 7UL;
89                 else
90                         val = ((val * 924375UL) >> 9UL) + 33000;
91                 voltage = (long)val;
92         } else {
93                 voltage = t ? t : -ETIMEDOUT;
94         }
95
96         battery->cell->disable(battery->pdev);
97         disable_irq(battery->irq);
98
99         mutex_unlock(&battery->lock);
100
101         return voltage;
102 }
103
104 static int jz_battery_get_capacity(struct power_supply *psy)
105 {
106         struct jz_battery *jz_battery = psy_to_jz_battery(psy);
107         struct power_supply_info *info = &jz_battery->pdata->info;
108         long voltage;
109         int ret;
110         int voltage_span;
111
112         voltage = jz_battery_read_voltage(jz_battery);
113
114         if (voltage < 0)
115                 return voltage;
116
117         voltage_span = info->voltage_max_design - info->voltage_min_design;
118         ret = ((voltage - info->voltage_min_design) * 100) / voltage_span;
119
120         if (ret > 100)
121                 ret = 100;
122         else if (ret < 0)
123                 ret = 0;
124
125         return ret;
126 }
127
128 static int jz_battery_get_property(struct power_supply *psy,
129         enum power_supply_property psp, union power_supply_propval *val)
130 {
131         struct jz_battery *jz_battery = psy_to_jz_battery(psy);
132         struct power_supply_info *info = &jz_battery->pdata->info;
133         long voltage;
134
135         switch (psp) {
136         case POWER_SUPPLY_PROP_STATUS:
137                 val->intval = jz_battery->status;
138                 break;
139         case POWER_SUPPLY_PROP_TECHNOLOGY:
140                 val->intval = jz_battery->pdata->info.technology;
141                 break;
142         case POWER_SUPPLY_PROP_HEALTH:
143                 voltage = jz_battery_read_voltage(jz_battery);
144                 if (voltage < info->voltage_min_design)
145                         val->intval = POWER_SUPPLY_HEALTH_DEAD;
146                 else
147                         val->intval = POWER_SUPPLY_HEALTH_GOOD;
148                 break;
149         case POWER_SUPPLY_PROP_CAPACITY:
150                 val->intval = jz_battery_get_capacity(psy);
151                 break;
152         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
153                 val->intval = jz_battery_read_voltage(jz_battery);
154                 if (val->intval < 0)
155                         return val->intval;
156                 break;
157         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
158                 val->intval = info->voltage_max_design;
159                 break;
160         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
161                 val->intval = info->voltage_min_design;
162                 break;
163         case POWER_SUPPLY_PROP_PRESENT:
164                 val->intval = 1;
165                 break;
166         default:
167                 return -EINVAL;
168         }
169         return 0;
170 }
171
172 static void jz_battery_external_power_changed(struct power_supply *psy)
173 {
174         struct jz_battery *jz_battery = psy_to_jz_battery(psy);
175
176         cancel_delayed_work(&jz_battery->work);
177         schedule_delayed_work(&jz_battery->work, 0);
178 }
179
180 static irqreturn_t jz_battery_charge_irq(int irq, void *data)
181 {
182         struct jz_battery *jz_battery = data;
183
184         cancel_delayed_work(&jz_battery->work);
185         schedule_delayed_work(&jz_battery->work, 0);
186
187         return IRQ_HANDLED;
188 }
189
190 static void jz_battery_update(struct jz_battery *jz_battery)
191 {
192         int status;
193         long voltage;
194         bool has_changed = false;
195         int is_charging;
196
197         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
198                 is_charging = gpio_get_value(jz_battery->pdata->gpio_charge);
199                 is_charging ^= jz_battery->pdata->gpio_charge_active_low;
200                 if (is_charging)
201                         status = POWER_SUPPLY_STATUS_CHARGING;
202                 else
203                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
204
205                 if (status != jz_battery->status) {
206                         jz_battery->status = status;
207                         has_changed = true;
208                 }
209         }
210
211         voltage = jz_battery_read_voltage(jz_battery);
212         if (abs(voltage - jz_battery->voltage) < 50000) {
213                 jz_battery->voltage = voltage;
214                 has_changed = true;
215         }
216
217         if (has_changed)
218                 power_supply_changed(&jz_battery->battery);
219 }
220
221 static enum power_supply_property jz_battery_properties[] = {
222         POWER_SUPPLY_PROP_STATUS,
223         POWER_SUPPLY_PROP_TECHNOLOGY,
224         POWER_SUPPLY_PROP_HEALTH,
225         POWER_SUPPLY_PROP_CAPACITY,
226         POWER_SUPPLY_PROP_VOLTAGE_NOW,
227         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
228         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
229         POWER_SUPPLY_PROP_PRESENT,
230 };
231
232 static void jz_battery_work(struct work_struct *work)
233 {
234         /* Too small interval will increase system workload */
235         const int interval = HZ * 30;
236         struct jz_battery *jz_battery = container_of(work, struct jz_battery,
237                                             work.work);
238
239         jz_battery_update(jz_battery);
240         schedule_delayed_work(&jz_battery->work, interval);
241 }
242
243 static int __devinit jz_battery_probe(struct platform_device *pdev)
244 {
245         int ret = 0;
246         struct jz_battery_platform_data *pdata = pdev->dev.parent->platform_data;
247         struct jz_battery *jz_battery;
248         struct power_supply *battery;
249
250         if (!pdata) {
251                 dev_err(&pdev->dev, "No platform_data supplied\n");
252                 return -ENXIO;
253         }
254
255         jz_battery = kzalloc(sizeof(*jz_battery), GFP_KERNEL);
256         if (!jz_battery) {
257                 dev_err(&pdev->dev, "Failed to allocate driver structure\n");
258                 return -ENOMEM;
259         }
260
261         jz_battery->cell = mfd_get_cell(pdev);
262
263         jz_battery->irq = platform_get_irq(pdev, 0);
264         if (jz_battery->irq < 0) {
265                 ret = jz_battery->irq;
266                 dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
267                 goto err_free;
268         }
269
270         jz_battery->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
271         if (!jz_battery->mem) {
272                 ret = -ENOENT;
273                 dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
274                 goto err_free;
275         }
276
277         jz_battery->mem = request_mem_region(jz_battery->mem->start,
278                                 resource_size(jz_battery->mem), pdev->name);
279         if (!jz_battery->mem) {
280                 ret = -EBUSY;
281                 dev_err(&pdev->dev, "Failed to request mmio memory region\n");
282                 goto err_free;
283         }
284
285         jz_battery->base = ioremap_nocache(jz_battery->mem->start,
286                                 resource_size(jz_battery->mem));
287         if (!jz_battery->base) {
288                 ret = -EBUSY;
289                 dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
290                 goto err_release_mem_region;
291         }
292
293         battery = &jz_battery->battery;
294         battery->name = pdata->info.name;
295         battery->type = POWER_SUPPLY_TYPE_BATTERY;
296         battery->properties     = jz_battery_properties;
297         battery->num_properties = ARRAY_SIZE(jz_battery_properties);
298         battery->get_property = jz_battery_get_property;
299         battery->external_power_changed = jz_battery_external_power_changed;
300         battery->use_for_apm = 1;
301
302         jz_battery->pdata = pdata;
303         jz_battery->pdev = pdev;
304
305         init_completion(&jz_battery->read_completion);
306         mutex_init(&jz_battery->lock);
307
308         INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
309
310         ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
311                         jz_battery);
312         if (ret) {
313                 dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
314                 goto err_iounmap;
315         }
316         disable_irq(jz_battery->irq);
317
318         if (gpio_is_valid(pdata->gpio_charge)) {
319                 ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
320                 if (ret) {
321                         dev_err(&pdev->dev, "charger state gpio request failed.\n");
322                         goto err_free_irq;
323                 }
324                 ret = gpio_direction_input(pdata->gpio_charge);
325                 if (ret) {
326                         dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
327                         goto err_free_gpio;
328                 }
329
330                 jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
331
332                 if (jz_battery->charge_irq >= 0) {
333                         ret = request_irq(jz_battery->charge_irq,
334                                     jz_battery_charge_irq,
335                                     IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
336                                     dev_name(&pdev->dev), jz_battery);
337                         if (ret) {
338                                 dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
339                                 goto err_free_gpio;
340                         }
341                 }
342         } else {
343                 jz_battery->charge_irq = -1;
344         }
345
346         if (jz_battery->pdata->info.voltage_max_design <= 2500000)
347                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
348                         JZ_ADC_CONFIG_BAT_MB);
349         else
350                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
351
352         ret = power_supply_register(&pdev->dev, &jz_battery->battery);
353         if (ret) {
354                 dev_err(&pdev->dev, "power supply battery register failed.\n");
355                 goto err_free_charge_irq;
356         }
357
358         platform_set_drvdata(pdev, jz_battery);
359         schedule_delayed_work(&jz_battery->work, 0);
360
361         return 0;
362
363 err_free_charge_irq:
364         if (jz_battery->charge_irq >= 0)
365                 free_irq(jz_battery->charge_irq, jz_battery);
366 err_free_gpio:
367         if (gpio_is_valid(pdata->gpio_charge))
368                 gpio_free(jz_battery->pdata->gpio_charge);
369 err_free_irq:
370         free_irq(jz_battery->irq, jz_battery);
371 err_iounmap:
372         platform_set_drvdata(pdev, NULL);
373         iounmap(jz_battery->base);
374 err_release_mem_region:
375         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
376 err_free:
377         kfree(jz_battery);
378         return ret;
379 }
380
381 static int __devexit jz_battery_remove(struct platform_device *pdev)
382 {
383         struct jz_battery *jz_battery = platform_get_drvdata(pdev);
384
385         cancel_delayed_work_sync(&jz_battery->work);
386
387         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
388                 if (jz_battery->charge_irq >= 0)
389                         free_irq(jz_battery->charge_irq, jz_battery);
390                 gpio_free(jz_battery->pdata->gpio_charge);
391         }
392
393         power_supply_unregister(&jz_battery->battery);
394
395         free_irq(jz_battery->irq, jz_battery);
396
397         iounmap(jz_battery->base);
398         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
399         kfree(jz_battery);
400
401         return 0;
402 }
403
404 #ifdef CONFIG_PM
405 static int jz_battery_suspend(struct device *dev)
406 {
407         struct jz_battery *jz_battery = dev_get_drvdata(dev);
408
409         cancel_delayed_work_sync(&jz_battery->work);
410         jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
411
412         return 0;
413 }
414
415 static int jz_battery_resume(struct device *dev)
416 {
417         struct jz_battery *jz_battery = dev_get_drvdata(dev);
418
419         schedule_delayed_work(&jz_battery->work, 0);
420
421         return 0;
422 }
423
424 static const struct dev_pm_ops jz_battery_pm_ops = {
425         .suspend        = jz_battery_suspend,
426         .resume         = jz_battery_resume,
427 };
428
429 #define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
430 #else
431 #define JZ_BATTERY_PM_OPS NULL
432 #endif
433
434 static struct platform_driver jz_battery_driver = {
435         .probe          = jz_battery_probe,
436         .remove         = __devexit_p(jz_battery_remove),
437         .driver = {
438                 .name = "jz4740-battery",
439                 .owner = THIS_MODULE,
440                 .pm = JZ_BATTERY_PM_OPS,
441         },
442 };
443
444 module_platform_driver(jz_battery_driver);
445
446 MODULE_ALIAS("platform:jz4740-battery");
447 MODULE_LICENSE("GPL");
448 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
449 MODULE_DESCRIPTION("JZ4740 SoC battery driver");