/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
 32struct 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
 55static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
 56{
 57	return container_of(psy, struct jz_battery, battery);
 58}
 59
 60static 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
 68static long jz_battery_read_voltage(struct jz_battery *battery)
 69{
 70	unsigned 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
104static 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
128static 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
172static 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
180static 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
190static 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
221static 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
232static 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
243static 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
363err_free_charge_irq:
364	if (jz_battery->charge_irq >= 0)
365		free_irq(jz_battery->charge_irq, jz_battery);
366err_free_gpio:
367	if (gpio_is_valid(pdata->gpio_charge))
368		gpio_free(jz_battery->pdata->gpio_charge);
369err_free_irq:
370	free_irq(jz_battery->irq, jz_battery);
371err_iounmap:
372	platform_set_drvdata(pdev, NULL);
373	iounmap(jz_battery->base);
374err_release_mem_region:
375	release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
376err_free:
377	kfree(jz_battery);
378	return ret;
379}
380
381static 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
405static 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
415static 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
424static 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
434static 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
444static int __init jz_battery_init(void)
445{
446	return platform_driver_register(&jz_battery_driver);
447}
448module_init(jz_battery_init);
449
450static void __exit jz_battery_exit(void)
451{
452	platform_driver_unregister(&jz_battery_driver);
453}
454module_exit(jz_battery_exit);
455
456MODULE_ALIAS("platform:jz4740-battery");
457MODULE_LICENSE("GPL");
458MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
459MODULE_DESCRIPTION("JZ4740 SoC battery driver");