2 * Battery measurement code for WM97xx
4 * based on tosa_battery.c
6 * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/platform_device.h>
18 #include <linux/power_supply.h>
19 #include <linux/wm97xx.h>
20 #include <linux/spinlock.h>
21 #include <linux/interrupt.h>
22 #include <linux/gpio.h>
23 #include <linux/irq.h>
24 #include <linux/slab.h>
26 static struct work_struct bat_work;
27 static DEFINE_MUTEX(work_lock);
28 static int bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
29 static enum power_supply_property *prop;
31 static unsigned long wm97xx_read_bat(struct power_supply *bat_ps)
33 struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps);
35 return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent),
36 pdata->batt_aux) * pdata->batt_mult /
40 static unsigned long wm97xx_read_temp(struct power_supply *bat_ps)
42 struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps);
44 return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent),
45 pdata->temp_aux) * pdata->temp_mult /
49 static int wm97xx_bat_get_property(struct power_supply *bat_ps,
50 enum power_supply_property psp,
51 union power_supply_propval *val)
53 struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps);
56 case POWER_SUPPLY_PROP_STATUS:
57 val->intval = bat_status;
59 case POWER_SUPPLY_PROP_TECHNOLOGY:
60 val->intval = pdata->batt_tech;
62 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
63 if (pdata->batt_aux >= 0)
64 val->intval = wm97xx_read_bat(bat_ps);
68 case POWER_SUPPLY_PROP_TEMP:
69 if (pdata->temp_aux >= 0)
70 val->intval = wm97xx_read_temp(bat_ps);
74 case POWER_SUPPLY_PROP_VOLTAGE_MAX:
75 if (pdata->max_voltage >= 0)
76 val->intval = pdata->max_voltage;
80 case POWER_SUPPLY_PROP_VOLTAGE_MIN:
81 if (pdata->min_voltage >= 0)
82 val->intval = pdata->min_voltage;
86 case POWER_SUPPLY_PROP_PRESENT:
95 static void wm97xx_bat_external_power_changed(struct power_supply *bat_ps)
97 schedule_work(&bat_work);
100 static void wm97xx_bat_update(struct power_supply *bat_ps)
102 int old_status = bat_status;
103 struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps);
105 mutex_lock(&work_lock);
107 bat_status = (pdata->charge_gpio >= 0) ?
108 (gpio_get_value(pdata->charge_gpio) ?
109 POWER_SUPPLY_STATUS_DISCHARGING :
110 POWER_SUPPLY_STATUS_CHARGING) :
111 POWER_SUPPLY_STATUS_UNKNOWN;
113 if (old_status != bat_status) {
114 pr_debug("%s: %i -> %i\n", bat_ps->desc->name, old_status,
116 power_supply_changed(bat_ps);
119 mutex_unlock(&work_lock);
122 static struct power_supply *bat_psy;
123 static struct power_supply_desc bat_psy_desc = {
124 .type = POWER_SUPPLY_TYPE_BATTERY,
125 .get_property = wm97xx_bat_get_property,
126 .external_power_changed = wm97xx_bat_external_power_changed,
130 static void wm97xx_bat_work(struct work_struct *work)
132 wm97xx_bat_update(bat_psy);
135 static irqreturn_t wm97xx_chrg_irq(int irq, void *data)
137 schedule_work(&bat_work);
142 static int wm97xx_bat_suspend(struct device *dev)
144 flush_work(&bat_work);
148 static int wm97xx_bat_resume(struct device *dev)
150 schedule_work(&bat_work);
154 static const struct dev_pm_ops wm97xx_bat_pm_ops = {
155 .suspend = wm97xx_bat_suspend,
156 .resume = wm97xx_bat_resume,
160 static int wm97xx_bat_probe(struct platform_device *dev)
163 int props = 1; /* POWER_SUPPLY_PROP_PRESENT */
165 struct wm97xx_batt_pdata *pdata = dev->dev.platform_data;
166 struct power_supply_config cfg = {};
169 dev_err(&dev->dev, "No platform data supplied\n");
173 cfg.drv_data = pdata;
178 if (gpio_is_valid(pdata->charge_gpio)) {
179 ret = gpio_request(pdata->charge_gpio, "BATT CHRG");
182 ret = gpio_direction_input(pdata->charge_gpio);
185 ret = request_irq(gpio_to_irq(pdata->charge_gpio),
190 props++; /* POWER_SUPPLY_PROP_STATUS */
193 if (pdata->batt_tech >= 0)
194 props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */
195 if (pdata->temp_aux >= 0)
196 props++; /* POWER_SUPPLY_PROP_TEMP */
197 if (pdata->batt_aux >= 0)
198 props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
199 if (pdata->max_voltage >= 0)
200 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
201 if (pdata->min_voltage >= 0)
202 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
204 prop = kcalloc(props, sizeof(*prop), GFP_KERNEL);
210 prop[i++] = POWER_SUPPLY_PROP_PRESENT;
211 if (pdata->charge_gpio >= 0)
212 prop[i++] = POWER_SUPPLY_PROP_STATUS;
213 if (pdata->batt_tech >= 0)
214 prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
215 if (pdata->temp_aux >= 0)
216 prop[i++] = POWER_SUPPLY_PROP_TEMP;
217 if (pdata->batt_aux >= 0)
218 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
219 if (pdata->max_voltage >= 0)
220 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
221 if (pdata->min_voltage >= 0)
222 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;
224 INIT_WORK(&bat_work, wm97xx_bat_work);
226 if (!pdata->batt_name) {
227 dev_info(&dev->dev, "Please consider setting proper battery "
228 "name in platform definition file, falling "
229 "back to name \"wm97xx-batt\"\n");
230 bat_psy_desc.name = "wm97xx-batt";
232 bat_psy_desc.name = pdata->batt_name;
234 bat_psy_desc.properties = prop;
235 bat_psy_desc.num_properties = props;
237 bat_psy = power_supply_register(&dev->dev, &bat_psy_desc, &cfg);
238 if (!IS_ERR(bat_psy)) {
239 schedule_work(&bat_work);
241 ret = PTR_ERR(bat_psy);
249 if (gpio_is_valid(pdata->charge_gpio))
250 free_irq(gpio_to_irq(pdata->charge_gpio), dev);
252 if (gpio_is_valid(pdata->charge_gpio))
253 gpio_free(pdata->charge_gpio);
258 static int wm97xx_bat_remove(struct platform_device *dev)
260 struct wm97xx_batt_pdata *pdata = dev->dev.platform_data;
262 if (pdata && gpio_is_valid(pdata->charge_gpio)) {
263 free_irq(gpio_to_irq(pdata->charge_gpio), dev);
264 gpio_free(pdata->charge_gpio);
266 cancel_work_sync(&bat_work);
267 power_supply_unregister(bat_psy);
272 static struct platform_driver wm97xx_bat_driver = {
274 .name = "wm97xx-battery",
276 .pm = &wm97xx_bat_pm_ops,
279 .probe = wm97xx_bat_probe,
280 .remove = wm97xx_bat_remove,
283 module_platform_driver(wm97xx_bat_driver);
285 MODULE_LICENSE("GPL");
286 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
287 MODULE_DESCRIPTION("WM97xx battery driver");