1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // iPAQ h1930/h1940/rx1950 battery controller driver
4 // Copyright (c) Vasily Khoruzhick
5 // Based on h1940_battery.c by Arnaud Patard
6
7 #include <linux/interrupt.h>
8 #include <linux/platform_device.h>
9 #include <linux/power_supply.h>
10 #include <linux/leds.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/err.h>
13 #include <linux/timer.h>
14 #include <linux/jiffies.h>
15 #include <linux/s3c_adc_battery.h>
16 #include <linux/errno.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19
20 #include <linux/soc/samsung/s3c-adc.h>
21
22 #define BAT_POLL_INTERVAL 10000 /* ms */
23 #define JITTER_DELAY 500 /* ms */
24
25 struct s3c_adc_bat {
26 struct power_supply *psy;
27 struct s3c_adc_client *client;
28 struct s3c_adc_bat_pdata *pdata;
29 struct gpio_desc *charge_finished;
30 int volt_value;
31 int cur_value;
32 unsigned int timestamp;
33 int level;
34 int status;
35 int cable_plugged:1;
36 };
37
38 static struct delayed_work bat_work;
39
s3c_adc_bat_ext_power_changed(struct power_supply * psy)40 static void s3c_adc_bat_ext_power_changed(struct power_supply *psy)
41 {
42 schedule_delayed_work(&bat_work,
43 msecs_to_jiffies(JITTER_DELAY));
44 }
45
gather_samples(struct s3c_adc_client * client,int num,int channel)46 static int gather_samples(struct s3c_adc_client *client, int num, int channel)
47 {
48 int value, i;
49
50 /* default to 1 if nothing is set */
51 if (num < 1)
52 num = 1;
53
54 value = 0;
55 for (i = 0; i < num; i++)
56 value += s3c_adc_read(client, channel);
57 value /= num;
58
59 return value;
60 }
61
62 static enum power_supply_property s3c_adc_backup_bat_props[] = {
63 POWER_SUPPLY_PROP_VOLTAGE_NOW,
64 POWER_SUPPLY_PROP_VOLTAGE_MIN,
65 POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
66 };
67
s3c_adc_backup_bat_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)68 static int s3c_adc_backup_bat_get_property(struct power_supply *psy,
69 enum power_supply_property psp,
70 union power_supply_propval *val)
71 {
72 struct s3c_adc_bat *bat = power_supply_get_drvdata(psy);
73
74 if (!bat) {
75 dev_err(&psy->dev, "%s: no battery infos ?!\n", __func__);
76 return -EINVAL;
77 }
78
79 if (bat->volt_value < 0 ||
80 jiffies_to_msecs(jiffies - bat->timestamp) >
81 BAT_POLL_INTERVAL) {
82 bat->volt_value = gather_samples(bat->client,
83 bat->pdata->backup_volt_samples,
84 bat->pdata->backup_volt_channel);
85 bat->volt_value *= bat->pdata->backup_volt_mult;
86 bat->timestamp = jiffies;
87 }
88
89 switch (psp) {
90 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
91 val->intval = bat->volt_value;
92 return 0;
93 case POWER_SUPPLY_PROP_VOLTAGE_MIN:
94 val->intval = bat->pdata->backup_volt_min;
95 return 0;
96 case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
97 val->intval = bat->pdata->backup_volt_max;
98 return 0;
99 default:
100 return -EINVAL;
101 }
102 }
103
104 static const struct power_supply_desc backup_bat_desc = {
105 .name = "backup-battery",
106 .type = POWER_SUPPLY_TYPE_BATTERY,
107 .properties = s3c_adc_backup_bat_props,
108 .num_properties = ARRAY_SIZE(s3c_adc_backup_bat_props),
109 .get_property = s3c_adc_backup_bat_get_property,
110 .use_for_apm = 1,
111 };
112
113 static struct s3c_adc_bat backup_bat;
114
115 static enum power_supply_property s3c_adc_main_bat_props[] = {
116 POWER_SUPPLY_PROP_STATUS,
117 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
118 POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
119 POWER_SUPPLY_PROP_CHARGE_NOW,
120 POWER_SUPPLY_PROP_VOLTAGE_NOW,
121 POWER_SUPPLY_PROP_CURRENT_NOW,
122 };
123
calc_full_volt(int volt_val,int cur_val,int impedance)124 static int calc_full_volt(int volt_val, int cur_val, int impedance)
125 {
126 return volt_val + cur_val * impedance / 1000;
127 }
128
charge_finished(struct s3c_adc_bat * bat)129 static int charge_finished(struct s3c_adc_bat *bat)
130 {
131 return gpiod_get_value(bat->charge_finished);
132 }
133
s3c_adc_bat_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)134 static int s3c_adc_bat_get_property(struct power_supply *psy,
135 enum power_supply_property psp,
136 union power_supply_propval *val)
137 {
138 struct s3c_adc_bat *bat = power_supply_get_drvdata(psy);
139
140 int new_level;
141 int full_volt;
142 const struct s3c_adc_bat_thresh *lut;
143 unsigned int lut_size;
144
145 if (!bat) {
146 dev_err(&psy->dev, "no battery infos ?!\n");
147 return -EINVAL;
148 }
149
150 lut = bat->pdata->lut_noac;
151 lut_size = bat->pdata->lut_noac_cnt;
152
153 if (bat->volt_value < 0 || bat->cur_value < 0 ||
154 jiffies_to_msecs(jiffies - bat->timestamp) >
155 BAT_POLL_INTERVAL) {
156 bat->volt_value = gather_samples(bat->client,
157 bat->pdata->volt_samples,
158 bat->pdata->volt_channel) * bat->pdata->volt_mult;
159 bat->cur_value = gather_samples(bat->client,
160 bat->pdata->current_samples,
161 bat->pdata->current_channel) * bat->pdata->current_mult;
162 bat->timestamp = jiffies;
163 }
164
165 if (bat->cable_plugged &&
166 (!bat->charge_finished ||
167 !charge_finished(bat))) {
168 lut = bat->pdata->lut_acin;
169 lut_size = bat->pdata->lut_acin_cnt;
170 }
171
172 new_level = 100000;
173 full_volt = calc_full_volt((bat->volt_value / 1000),
174 (bat->cur_value / 1000), bat->pdata->internal_impedance);
175
176 if (full_volt < calc_full_volt(lut->volt, lut->cur,
177 bat->pdata->internal_impedance)) {
178 lut_size--;
179 while (lut_size--) {
180 int lut_volt1;
181 int lut_volt2;
182
183 lut_volt1 = calc_full_volt(lut[0].volt, lut[0].cur,
184 bat->pdata->internal_impedance);
185 lut_volt2 = calc_full_volt(lut[1].volt, lut[1].cur,
186 bat->pdata->internal_impedance);
187 if (full_volt < lut_volt1 && full_volt >= lut_volt2) {
188 new_level = (lut[1].level +
189 (lut[0].level - lut[1].level) *
190 (full_volt - lut_volt2) /
191 (lut_volt1 - lut_volt2)) * 1000;
192 break;
193 }
194 new_level = lut[1].level * 1000;
195 lut++;
196 }
197 }
198
199 bat->level = new_level;
200
201 switch (psp) {
202 case POWER_SUPPLY_PROP_STATUS:
203 if (!bat->charge_finished)
204 val->intval = bat->level == 100000 ?
205 POWER_SUPPLY_STATUS_FULL : bat->status;
206 else
207 val->intval = bat->status;
208 return 0;
209 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
210 val->intval = 100000;
211 return 0;
212 case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
213 val->intval = 0;
214 return 0;
215 case POWER_SUPPLY_PROP_CHARGE_NOW:
216 val->intval = bat->level;
217 return 0;
218 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
219 val->intval = bat->volt_value;
220 return 0;
221 case POWER_SUPPLY_PROP_CURRENT_NOW:
222 val->intval = bat->cur_value;
223 return 0;
224 default:
225 return -EINVAL;
226 }
227 }
228
229 static const struct power_supply_desc main_bat_desc = {
230 .name = "main-battery",
231 .type = POWER_SUPPLY_TYPE_BATTERY,
232 .properties = s3c_adc_main_bat_props,
233 .num_properties = ARRAY_SIZE(s3c_adc_main_bat_props),
234 .get_property = s3c_adc_bat_get_property,
235 .external_power_changed = s3c_adc_bat_ext_power_changed,
236 .use_for_apm = 1,
237 };
238
239 static struct s3c_adc_bat main_bat;
240
s3c_adc_bat_work(struct work_struct * work)241 static void s3c_adc_bat_work(struct work_struct *work)
242 {
243 struct s3c_adc_bat *bat = &main_bat;
244 int is_charged;
245 int is_plugged;
246 static int was_plugged;
247
248 is_plugged = power_supply_am_i_supplied(bat->psy);
249 bat->cable_plugged = is_plugged;
250 if (is_plugged != was_plugged) {
251 was_plugged = is_plugged;
252 if (is_plugged) {
253 if (bat->pdata->enable_charger)
254 bat->pdata->enable_charger();
255 bat->status = POWER_SUPPLY_STATUS_CHARGING;
256 } else {
257 if (bat->pdata->disable_charger)
258 bat->pdata->disable_charger();
259 bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
260 }
261 } else {
262 if (bat->charge_finished && is_plugged) {
263 is_charged = charge_finished(&main_bat);
264 if (is_charged) {
265 if (bat->pdata->disable_charger)
266 bat->pdata->disable_charger();
267 bat->status = POWER_SUPPLY_STATUS_FULL;
268 } else {
269 if (bat->pdata->enable_charger)
270 bat->pdata->enable_charger();
271 bat->status = POWER_SUPPLY_STATUS_CHARGING;
272 }
273 }
274 }
275
276 power_supply_changed(bat->psy);
277 }
278
s3c_adc_bat_charged(int irq,void * dev_id)279 static irqreturn_t s3c_adc_bat_charged(int irq, void *dev_id)
280 {
281 schedule_delayed_work(&bat_work,
282 msecs_to_jiffies(JITTER_DELAY));
283 return IRQ_HANDLED;
284 }
285
s3c_adc_bat_probe(struct platform_device * pdev)286 static int s3c_adc_bat_probe(struct platform_device *pdev)
287 {
288 struct s3c_adc_client *client;
289 struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
290 struct power_supply_config psy_cfg = {};
291 struct gpio_desc *gpiod;
292 int ret;
293
294 client = s3c_adc_register(pdev, NULL, NULL, 0);
295 if (IS_ERR(client)) {
296 dev_err(&pdev->dev, "cannot register adc\n");
297 return PTR_ERR(client);
298 }
299
300 platform_set_drvdata(pdev, client);
301
302 gpiod = devm_gpiod_get_optional(&pdev->dev, "charge-status", GPIOD_IN);
303 if (IS_ERR(gpiod)) {
304 /* Could be probe deferral etc */
305 ret = PTR_ERR(gpiod);
306 dev_err(&pdev->dev, "no GPIO %d\n", ret);
307 return ret;
308 }
309
310 main_bat.client = client;
311 main_bat.pdata = pdata;
312 main_bat.charge_finished = gpiod;
313 main_bat.volt_value = -1;
314 main_bat.cur_value = -1;
315 main_bat.cable_plugged = 0;
316 main_bat.status = POWER_SUPPLY_STATUS_DISCHARGING;
317 psy_cfg.drv_data = &main_bat;
318
319 main_bat.psy = power_supply_register(&pdev->dev, &main_bat_desc, &psy_cfg);
320 if (IS_ERR(main_bat.psy)) {
321 ret = PTR_ERR(main_bat.psy);
322 goto err_reg_main;
323 }
324 if (pdata->backup_volt_mult) {
325 const struct power_supply_config backup_psy_cfg
326 = { .drv_data = &backup_bat, };
327
328 backup_bat.client = client;
329 backup_bat.pdata = pdev->dev.platform_data;
330 backup_bat.charge_finished = gpiod;
331 backup_bat.volt_value = -1;
332 backup_bat.psy = power_supply_register(&pdev->dev,
333 &backup_bat_desc,
334 &backup_psy_cfg);
335 if (IS_ERR(backup_bat.psy)) {
336 ret = PTR_ERR(backup_bat.psy);
337 goto err_reg_backup;
338 }
339 }
340
341 INIT_DELAYED_WORK(&bat_work, s3c_adc_bat_work);
342
343 if (gpiod) {
344 ret = request_irq(gpiod_to_irq(gpiod),
345 s3c_adc_bat_charged,
346 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
347 "battery charged", NULL);
348 if (ret)
349 goto err_irq;
350 }
351
352 if (pdata->init) {
353 ret = pdata->init();
354 if (ret)
355 goto err_platform;
356 }
357
358 dev_info(&pdev->dev, "successfully loaded\n");
359 device_init_wakeup(&pdev->dev, 1);
360
361 /* Schedule timer to check current status */
362 schedule_delayed_work(&bat_work,
363 msecs_to_jiffies(JITTER_DELAY));
364
365 return 0;
366
367 err_platform:
368 if (gpiod)
369 free_irq(gpiod_to_irq(gpiod), NULL);
370 err_irq:
371 if (pdata->backup_volt_mult)
372 power_supply_unregister(backup_bat.psy);
373 err_reg_backup:
374 power_supply_unregister(main_bat.psy);
375 err_reg_main:
376 return ret;
377 }
378
s3c_adc_bat_remove(struct platform_device * pdev)379 static int s3c_adc_bat_remove(struct platform_device *pdev)
380 {
381 struct s3c_adc_client *client = platform_get_drvdata(pdev);
382 struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
383
384 power_supply_unregister(main_bat.psy);
385 if (pdata->backup_volt_mult)
386 power_supply_unregister(backup_bat.psy);
387
388 s3c_adc_release(client);
389
390 if (main_bat.charge_finished)
391 free_irq(gpiod_to_irq(main_bat.charge_finished), NULL);
392
393 cancel_delayed_work_sync(&bat_work);
394
395 if (pdata->exit)
396 pdata->exit();
397
398 return 0;
399 }
400
401 #ifdef CONFIG_PM
s3c_adc_bat_suspend(struct platform_device * pdev,pm_message_t state)402 static int s3c_adc_bat_suspend(struct platform_device *pdev,
403 pm_message_t state)
404 {
405 if (main_bat.charge_finished) {
406 if (device_may_wakeup(&pdev->dev))
407 enable_irq_wake(
408 gpiod_to_irq(main_bat.charge_finished));
409 else {
410 disable_irq(gpiod_to_irq(main_bat.charge_finished));
411 main_bat.pdata->disable_charger();
412 }
413 }
414
415 return 0;
416 }
417
s3c_adc_bat_resume(struct platform_device * pdev)418 static int s3c_adc_bat_resume(struct platform_device *pdev)
419 {
420 if (main_bat.charge_finished) {
421 if (device_may_wakeup(&pdev->dev))
422 disable_irq_wake(
423 gpiod_to_irq(main_bat.charge_finished));
424 else
425 enable_irq(gpiod_to_irq(main_bat.charge_finished));
426 }
427
428 /* Schedule timer to check current status */
429 schedule_delayed_work(&bat_work,
430 msecs_to_jiffies(JITTER_DELAY));
431
432 return 0;
433 }
434 #else
435 #define s3c_adc_bat_suspend NULL
436 #define s3c_adc_bat_resume NULL
437 #endif
438
439 static struct platform_driver s3c_adc_bat_driver = {
440 .driver = {
441 .name = "s3c-adc-battery",
442 },
443 .probe = s3c_adc_bat_probe,
444 .remove = s3c_adc_bat_remove,
445 .suspend = s3c_adc_bat_suspend,
446 .resume = s3c_adc_bat_resume,
447 };
448
449 module_platform_driver(s3c_adc_bat_driver);
450
451 MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
452 MODULE_DESCRIPTION("iPAQ H1930/H1940/RX1950 battery controller driver");
453 MODULE_LICENSE("GPL");
454