1 /*
2 * Generic battery driver code using IIO
3 * Copyright (C) 2012, Anish Kumar <anish198519851985@gmail.com>
4 * based on jz4740-battery.c
5 * based on s3c_adc_battery.c
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License. See the file COPYING in the main directory of this archive for
9 * more details.
10 *
11 */
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/power_supply.h>
15 #include <linux/gpio.h>
16 #include <linux/err.h>
17 #include <linux/timer.h>
18 #include <linux/jiffies.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/iio/consumer.h>
24 #include <linux/iio/types.h>
25 #include <linux/power/generic-adc-battery.h>
26
27 #define JITTER_DEFAULT 10 /* hope 10ms is enough */
28
29 enum gab_chan_type {
30 GAB_VOLTAGE = 0,
31 GAB_CURRENT,
32 GAB_POWER,
33 GAB_MAX_CHAN_TYPE
34 };
35
36 /*
37 * gab_chan_name suggests the standard channel names for commonly used
38 * channel types.
39 */
40 static const char *const gab_chan_name[] = {
41 [GAB_VOLTAGE] = "voltage",
42 [GAB_CURRENT] = "current",
43 [GAB_POWER] = "power",
44 };
45
46 struct gab {
47 struct power_supply *psy;
48 struct power_supply_desc psy_desc;
49 struct iio_channel *channel[GAB_MAX_CHAN_TYPE];
50 struct gab_platform_data *pdata;
51 struct delayed_work bat_work;
52 int level;
53 int status;
54 bool cable_plugged;
55 };
56
to_generic_bat(struct power_supply * psy)57 static struct gab *to_generic_bat(struct power_supply *psy)
58 {
59 return power_supply_get_drvdata(psy);
60 }
61
gab_ext_power_changed(struct power_supply * psy)62 static void gab_ext_power_changed(struct power_supply *psy)
63 {
64 struct gab *adc_bat = to_generic_bat(psy);
65
66 schedule_delayed_work(&adc_bat->bat_work, msecs_to_jiffies(0));
67 }
68
69 static const enum power_supply_property gab_props[] = {
70 POWER_SUPPLY_PROP_STATUS,
71 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
72 POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
73 POWER_SUPPLY_PROP_CHARGE_NOW,
74 POWER_SUPPLY_PROP_VOLTAGE_NOW,
75 POWER_SUPPLY_PROP_CURRENT_NOW,
76 POWER_SUPPLY_PROP_TECHNOLOGY,
77 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
78 POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
79 POWER_SUPPLY_PROP_MODEL_NAME,
80 };
81
82 /*
83 * This properties are set based on the received platform data and this
84 * should correspond one-to-one with enum chan_type.
85 */
86 static const enum power_supply_property gab_dyn_props[] = {
87 POWER_SUPPLY_PROP_VOLTAGE_NOW,
88 POWER_SUPPLY_PROP_CURRENT_NOW,
89 POWER_SUPPLY_PROP_POWER_NOW,
90 };
91
gab_charge_finished(struct gab * adc_bat)92 static bool gab_charge_finished(struct gab *adc_bat)
93 {
94 struct gab_platform_data *pdata = adc_bat->pdata;
95 bool ret = gpio_get_value(pdata->gpio_charge_finished);
96 bool inv = pdata->gpio_inverted;
97
98 if (!gpio_is_valid(pdata->gpio_charge_finished))
99 return false;
100 return ret ^ inv;
101 }
102
gab_get_status(struct gab * adc_bat)103 static int gab_get_status(struct gab *adc_bat)
104 {
105 struct gab_platform_data *pdata = adc_bat->pdata;
106 struct power_supply_info *bat_info;
107
108 bat_info = &pdata->battery_info;
109 if (adc_bat->level == bat_info->charge_full_design)
110 return POWER_SUPPLY_STATUS_FULL;
111 return adc_bat->status;
112 }
113
gab_prop_to_chan(enum power_supply_property psp)114 static enum gab_chan_type gab_prop_to_chan(enum power_supply_property psp)
115 {
116 switch (psp) {
117 case POWER_SUPPLY_PROP_POWER_NOW:
118 return GAB_POWER;
119 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
120 return GAB_VOLTAGE;
121 case POWER_SUPPLY_PROP_CURRENT_NOW:
122 return GAB_CURRENT;
123 default:
124 WARN_ON(1);
125 break;
126 }
127 return GAB_POWER;
128 }
129
read_channel(struct gab * adc_bat,enum power_supply_property psp,int * result)130 static int read_channel(struct gab *adc_bat, enum power_supply_property psp,
131 int *result)
132 {
133 int ret;
134 int chan_index;
135
136 chan_index = gab_prop_to_chan(psp);
137 ret = iio_read_channel_processed(adc_bat->channel[chan_index],
138 result);
139 if (ret < 0)
140 pr_err("read channel error\n");
141 else
142 *result *= 1000;
143
144 return ret;
145 }
146
gab_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)147 static int gab_get_property(struct power_supply *psy,
148 enum power_supply_property psp, union power_supply_propval *val)
149 {
150 struct gab *adc_bat;
151 struct gab_platform_data *pdata;
152 struct power_supply_info *bat_info;
153 int result = 0;
154 int ret = 0;
155
156 adc_bat = to_generic_bat(psy);
157 if (!adc_bat) {
158 dev_err(&psy->dev, "no battery infos ?!\n");
159 return -EINVAL;
160 }
161 pdata = adc_bat->pdata;
162 bat_info = &pdata->battery_info;
163
164 switch (psp) {
165 case POWER_SUPPLY_PROP_STATUS:
166 val->intval = gab_get_status(adc_bat);
167 break;
168 case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
169 val->intval = 0;
170 break;
171 case POWER_SUPPLY_PROP_CHARGE_NOW:
172 val->intval = pdata->cal_charge(result);
173 break;
174 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
175 case POWER_SUPPLY_PROP_CURRENT_NOW:
176 case POWER_SUPPLY_PROP_POWER_NOW:
177 ret = read_channel(adc_bat, psp, &result);
178 if (ret < 0)
179 goto err;
180 val->intval = result;
181 break;
182 case POWER_SUPPLY_PROP_TECHNOLOGY:
183 val->intval = bat_info->technology;
184 break;
185 case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
186 val->intval = bat_info->voltage_min_design;
187 break;
188 case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
189 val->intval = bat_info->voltage_max_design;
190 break;
191 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
192 val->intval = bat_info->charge_full_design;
193 break;
194 case POWER_SUPPLY_PROP_MODEL_NAME:
195 val->strval = bat_info->name;
196 break;
197 default:
198 return -EINVAL;
199 }
200 err:
201 return ret;
202 }
203
gab_work(struct work_struct * work)204 static void gab_work(struct work_struct *work)
205 {
206 struct gab *adc_bat;
207 struct delayed_work *delayed_work;
208 bool is_plugged;
209 int status;
210
211 delayed_work = to_delayed_work(work);
212 adc_bat = container_of(delayed_work, struct gab, bat_work);
213 status = adc_bat->status;
214
215 is_plugged = power_supply_am_i_supplied(adc_bat->psy);
216 adc_bat->cable_plugged = is_plugged;
217
218 if (!is_plugged)
219 adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
220 else if (gab_charge_finished(adc_bat))
221 adc_bat->status = POWER_SUPPLY_STATUS_NOT_CHARGING;
222 else
223 adc_bat->status = POWER_SUPPLY_STATUS_CHARGING;
224
225 if (status != adc_bat->status)
226 power_supply_changed(adc_bat->psy);
227 }
228
gab_charged(int irq,void * dev_id)229 static irqreturn_t gab_charged(int irq, void *dev_id)
230 {
231 struct gab *adc_bat = dev_id;
232 struct gab_platform_data *pdata = adc_bat->pdata;
233 int delay;
234
235 delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
236 schedule_delayed_work(&adc_bat->bat_work,
237 msecs_to_jiffies(delay));
238 return IRQ_HANDLED;
239 }
240
gab_probe(struct platform_device * pdev)241 static int gab_probe(struct platform_device *pdev)
242 {
243 struct gab *adc_bat;
244 struct power_supply_desc *psy_desc;
245 struct power_supply_config psy_cfg = {};
246 struct gab_platform_data *pdata = pdev->dev.platform_data;
247 enum power_supply_property *properties;
248 int ret = 0;
249 int chan;
250 int index = ARRAY_SIZE(gab_props);
251 bool any = false;
252
253 adc_bat = devm_kzalloc(&pdev->dev, sizeof(*adc_bat), GFP_KERNEL);
254 if (!adc_bat) {
255 dev_err(&pdev->dev, "failed to allocate memory\n");
256 return -ENOMEM;
257 }
258
259 psy_cfg.drv_data = adc_bat;
260 psy_desc = &adc_bat->psy_desc;
261 psy_desc->name = pdata->battery_info.name;
262
263 /* bootup default values for the battery */
264 adc_bat->cable_plugged = false;
265 adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
266 psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
267 psy_desc->get_property = gab_get_property;
268 psy_desc->external_power_changed = gab_ext_power_changed;
269 adc_bat->pdata = pdata;
270
271 /*
272 * copying the static properties and allocating extra memory for holding
273 * the extra configurable properties received from platform data.
274 */
275 properties = kcalloc(ARRAY_SIZE(gab_props) +
276 ARRAY_SIZE(gab_chan_name),
277 sizeof(*properties),
278 GFP_KERNEL);
279 if (!properties) {
280 ret = -ENOMEM;
281 goto first_mem_fail;
282 }
283
284 memcpy(properties, gab_props, sizeof(gab_props));
285
286 /*
287 * getting channel from iio and copying the battery properties
288 * based on the channel supported by consumer device.
289 */
290 for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
291 adc_bat->channel[chan] = iio_channel_get(&pdev->dev,
292 gab_chan_name[chan]);
293 if (IS_ERR(adc_bat->channel[chan])) {
294 ret = PTR_ERR(adc_bat->channel[chan]);
295 adc_bat->channel[chan] = NULL;
296 } else {
297 /* copying properties for supported channels only */
298 int index2;
299
300 for (index2 = 0; index2 < index; index2++) {
301 if (properties[index2] == gab_dyn_props[chan])
302 break; /* already known */
303 }
304 if (index2 == index) /* really new */
305 properties[index++] = gab_dyn_props[chan];
306 any = true;
307 }
308 }
309
310 /* none of the channels are supported so let's bail out */
311 if (!any) {
312 ret = -ENODEV;
313 goto second_mem_fail;
314 }
315
316 /*
317 * Total number of properties is equal to static properties
318 * plus the dynamic properties.Some properties may not be set
319 * as come channels may be not be supported by the device.So
320 * we need to take care of that.
321 */
322 psy_desc->properties = properties;
323 psy_desc->num_properties = index;
324
325 adc_bat->psy = power_supply_register(&pdev->dev, psy_desc, &psy_cfg);
326 if (IS_ERR(adc_bat->psy)) {
327 ret = PTR_ERR(adc_bat->psy);
328 goto err_reg_fail;
329 }
330
331 INIT_DELAYED_WORK(&adc_bat->bat_work, gab_work);
332
333 if (gpio_is_valid(pdata->gpio_charge_finished)) {
334 int irq;
335 ret = gpio_request(pdata->gpio_charge_finished, "charged");
336 if (ret)
337 goto gpio_req_fail;
338
339 irq = gpio_to_irq(pdata->gpio_charge_finished);
340 ret = request_any_context_irq(irq, gab_charged,
341 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
342 "battery charged", adc_bat);
343 if (ret < 0)
344 goto err_gpio;
345 }
346
347 platform_set_drvdata(pdev, adc_bat);
348
349 /* Schedule timer to check current status */
350 schedule_delayed_work(&adc_bat->bat_work,
351 msecs_to_jiffies(0));
352 return 0;
353
354 err_gpio:
355 gpio_free(pdata->gpio_charge_finished);
356 gpio_req_fail:
357 power_supply_unregister(adc_bat->psy);
358 err_reg_fail:
359 for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
360 if (adc_bat->channel[chan])
361 iio_channel_release(adc_bat->channel[chan]);
362 }
363 second_mem_fail:
364 kfree(properties);
365 first_mem_fail:
366 return ret;
367 }
368
gab_remove(struct platform_device * pdev)369 static int gab_remove(struct platform_device *pdev)
370 {
371 int chan;
372 struct gab *adc_bat = platform_get_drvdata(pdev);
373 struct gab_platform_data *pdata = adc_bat->pdata;
374
375 power_supply_unregister(adc_bat->psy);
376
377 if (gpio_is_valid(pdata->gpio_charge_finished)) {
378 free_irq(gpio_to_irq(pdata->gpio_charge_finished), adc_bat);
379 gpio_free(pdata->gpio_charge_finished);
380 }
381
382 for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
383 if (adc_bat->channel[chan])
384 iio_channel_release(adc_bat->channel[chan]);
385 }
386
387 kfree(adc_bat->psy_desc.properties);
388 cancel_delayed_work_sync(&adc_bat->bat_work);
389 return 0;
390 }
391
gab_suspend(struct device * dev)392 static int __maybe_unused gab_suspend(struct device *dev)
393 {
394 struct gab *adc_bat = dev_get_drvdata(dev);
395
396 cancel_delayed_work_sync(&adc_bat->bat_work);
397 adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
398 return 0;
399 }
400
gab_resume(struct device * dev)401 static int __maybe_unused gab_resume(struct device *dev)
402 {
403 struct gab *adc_bat = dev_get_drvdata(dev);
404 struct gab_platform_data *pdata = adc_bat->pdata;
405 int delay;
406
407 delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
408
409 /* Schedule timer to check current status */
410 schedule_delayed_work(&adc_bat->bat_work,
411 msecs_to_jiffies(delay));
412 return 0;
413 }
414
415 static SIMPLE_DEV_PM_OPS(gab_pm_ops, gab_suspend, gab_resume);
416
417 static struct platform_driver gab_driver = {
418 .driver = {
419 .name = "generic-adc-battery",
420 .pm = &gab_pm_ops,
421 },
422 .probe = gab_probe,
423 .remove = gab_remove,
424 };
425 module_platform_driver(gab_driver);
426
427 MODULE_AUTHOR("anish kumar <anish198519851985@gmail.com>");
428 MODULE_DESCRIPTION("generic battery driver using IIO");
429 MODULE_LICENSE("GPL");
430