powerpc/mm: Avoid calling arch_enter/leave_lazy_mmu() in set_ptes
[platform/kernel/linux-starfive.git] / drivers / power / supply / rk817_charger.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Charger Driver for Rockchip rk817
4  *
5  * Copyright (c) 2021 Maya Matuszczyk <maccraft123mc@gmail.com>
6  *
7  * Authors: Maya Matuszczyk <maccraft123mc@gmail.com>
8  *          Chris Morgan <macromorgan@hotmail.com>
9  */
10
11 #include <asm/unaligned.h>
12 #include <linux/devm-helpers.h>
13 #include <linux/mfd/rk808.h>
14 #include <linux/irq.h>
15 #include <linux/of.h>
16 #include <linux/platform_device.h>
17 #include <linux/power_supply.h>
18 #include <linux/regmap.h>
19
20 /* Charging statuses reported by hardware register */
21 enum rk817_charge_status {
22         CHRG_OFF,
23         DEAD_CHRG,
24         TRICKLE_CHRG,
25         CC_OR_CV_CHRG,
26         CHARGE_FINISH,
27         USB_OVER_VOL,
28         BAT_TMP_ERR,
29         BAT_TIM_ERR,
30 };
31
32 /*
33  * Max charging current read to/written from hardware register.
34  * Note how highest value corresponding to 0x7 is the lowest
35  * current, this is per the datasheet.
36  */
37 enum rk817_chg_cur {
38         CHG_1A,
39         CHG_1_5A,
40         CHG_2A,
41         CHG_2_5A,
42         CHG_2_75A,
43         CHG_3A,
44         CHG_3_5A,
45         CHG_0_5A,
46 };
47
48 struct rk817_charger {
49         struct device *dev;
50         struct rk808 *rk808;
51
52         struct power_supply *bat_ps;
53         struct power_supply *chg_ps;
54         bool plugged_in;
55         bool battery_present;
56
57         /*
58          * voltage_k and voltage_b values are used to calibrate the ADC
59          * voltage readings. While they are documented in the BSP kernel and
60          * datasheet as voltage_k and voltage_b, there is no further
61          * information explaining them in more detail.
62          */
63
64         uint32_t voltage_k;
65         uint32_t voltage_b;
66
67         /*
68          * soc - state of charge - like the BSP this is stored as a percentage,
69          * to the thousandth. BSP has a display state of charge (dsoc) and a
70          * remaining state of charge (rsoc). This value will be used for both
71          * purposes here so we don't do any fancy math to try and "smooth" the
72          * charge and just report it as it is. Note for example an soc of 100
73          * is stored as 100000, an soc of 50 is stored as 50000, etc.
74          */
75         int soc;
76
77         /*
78          * Capacity of battery when fully charged, equal or less than design
79          * capacity depending upon wear. BSP kernel saves to nvram in mAh,
80          * so this value is in mAh not the standard uAh.
81          */
82         int fcc_mah;
83
84         /*
85          * Calibrate the SOC on a fully charged battery, this way we can use
86          * the calibrated SOC value to correct for columb counter drift.
87          */
88         bool soc_cal;
89
90         /* Implementation specific immutable properties from device tree */
91         int res_div;
92         int sleep_enter_current_ua;
93         int sleep_filter_current_ua;
94         int bat_charge_full_design_uah;
95         int bat_voltage_min_design_uv;
96         int bat_voltage_max_design_uv;
97
98         /* Values updated periodically by driver for display. */
99         int charge_now_uah;
100         int volt_avg_uv;
101         int cur_avg_ua;
102         int max_chg_cur_ua;
103         int max_chg_volt_uv;
104         int charge_status;
105         int charger_input_volt_avg_uv;
106
107         /* Work queue to periodically update values. */
108         struct delayed_work work;
109 };
110
111 /* ADC coefficients extracted from BSP kernel */
112 #define ADC_TO_CURRENT(adc_value, res_div)      \
113         (adc_value * 172 / res_div)
114
115 #define CURRENT_TO_ADC(current, samp_res)       \
116         (current * samp_res / 172)
117
118 #define CHARGE_TO_ADC(capacity, res_div)        \
119         (capacity * res_div * 3600 / 172 * 1000)
120
121 #define ADC_TO_CHARGE_UAH(adc_value, res_div)   \
122         (adc_value / 3600 * 172 / res_div)
123
124 static int rk817_chg_cur_to_reg(u32 chg_cur_ma)
125 {
126         if (chg_cur_ma >= 3500)
127                 return CHG_3_5A;
128         else if (chg_cur_ma >= 3000)
129                 return CHG_3A;
130         else if (chg_cur_ma >= 2750)
131                 return CHG_2_75A;
132         else if (chg_cur_ma >= 2500)
133                 return CHG_2_5A;
134         else if (chg_cur_ma >= 2000)
135                 return CHG_2A;
136         else if (chg_cur_ma >= 1500)
137                 return CHG_1_5A;
138         else if (chg_cur_ma >= 1000)
139                 return CHG_1A;
140         else if (chg_cur_ma >= 500)
141                 return CHG_0_5A;
142         else
143                 return -EINVAL;
144 }
145
146 static int rk817_chg_cur_from_reg(u8 reg)
147 {
148         switch (reg) {
149         case CHG_0_5A:
150                 return 500000;
151         case CHG_1A:
152                 return 1000000;
153         case CHG_1_5A:
154                 return 1500000;
155         case CHG_2A:
156                 return 2000000;
157         case CHG_2_5A:
158                 return 2500000;
159         case CHG_2_75A:
160                 return 2750000;
161         case CHG_3A:
162                 return 3000000;
163         case CHG_3_5A:
164                 return 3500000;
165         default:
166                 return -EINVAL;
167         }
168 }
169
170 static void rk817_bat_calib_vol(struct rk817_charger *charger)
171 {
172         uint32_t vcalib0 = 0;
173         uint32_t vcalib1 = 0;
174         u8 bulk_reg[2];
175
176         /* calibrate voltage */
177         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB0_H,
178                          bulk_reg, 2);
179         vcalib0 = get_unaligned_be16(bulk_reg);
180
181         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB1_H,
182                          bulk_reg, 2);
183         vcalib1 = get_unaligned_be16(bulk_reg);
184
185         /* values were taken from BSP kernel */
186         charger->voltage_k = (4025 - 2300) * 1000 /
187                              ((vcalib1 - vcalib0) ? (vcalib1 - vcalib0) : 1);
188         charger->voltage_b = 4025 - (charger->voltage_k * vcalib1) / 1000;
189 }
190
191 static void rk817_bat_calib_cur(struct rk817_charger *charger)
192 {
193         u8 bulk_reg[2];
194
195         /* calibrate current */
196         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_IOFFSET_H,
197                          bulk_reg, 2);
198         regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_CAL_OFFSET_H,
199                           bulk_reg, 2);
200 }
201
202 /*
203  * note that only the fcc_mah is really used by this driver, the other values
204  * are to ensure we can remain backwards compatible with the BSP kernel.
205  */
206 static int rk817_record_battery_nvram_values(struct rk817_charger *charger)
207 {
208         u8 bulk_reg[3];
209         int ret, rsoc;
210
211         /*
212          * write the soc value to the nvram location used by the BSP kernel
213          * for the dsoc value.
214          */
215         put_unaligned_le24(charger->soc, bulk_reg);
216         ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_R1,
217                                 bulk_reg, 3);
218         if (ret < 0)
219                 return ret;
220         /*
221          * write the remaining capacity in mah to the nvram location used by
222          * the BSP kernel for the rsoc value.
223          */
224         rsoc = (charger->soc * charger->fcc_mah) / 100000;
225         put_unaligned_le24(rsoc, bulk_reg);
226         ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA0,
227                                 bulk_reg, 3);
228         if (ret < 0)
229                 return ret;
230         /* write the fcc_mah in mAh, just as the BSP kernel does. */
231         put_unaligned_le24(charger->fcc_mah, bulk_reg);
232         ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA3,
233                                 bulk_reg, 3);
234         if (ret < 0)
235                 return ret;
236
237         return 0;
238 }
239
240 static int rk817_bat_calib_cap(struct rk817_charger *charger)
241 {
242         struct rk808 *rk808 = charger->rk808;
243         int tmp, charge_now, charge_now_adc, volt_avg;
244         u8 bulk_reg[4];
245
246         /* Calibrate the soc and fcc on a fully charged battery */
247
248         if (charger->charge_status == CHARGE_FINISH && (!charger->soc_cal)) {
249                 /*
250                  * soc should be 100000 and columb counter should show the full
251                  * charge capacity. Note that if the device is unplugged for a
252                  * period of several days the columb counter will have a large
253                  * margin of error, so setting it back to the full charge on
254                  * a completed charge cycle should correct this (my device was
255                  * showing 33% battery after 3 days unplugged when it should
256                  * have been closer to 95% based on voltage and charge
257                  * current).
258                  */
259
260                 charger->soc = 100000;
261                 charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah,
262                                                charger->res_div);
263                 put_unaligned_be32(charge_now_adc, bulk_reg);
264                 regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3,
265                                   bulk_reg, 4);
266
267                 charger->soc_cal = 1;
268                 dev_dbg(charger->dev,
269                         "Fully charged. SOC is %d, full capacity is %d\n",
270                         charger->soc, charger->fcc_mah * 1000);
271         }
272
273         /*
274          * The columb counter can drift up slightly, so we should correct for
275          * it. But don't correct it until we're at 100% soc.
276          */
277         if (charger->charge_status == CHARGE_FINISH && charger->soc_cal) {
278                 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
279                                  bulk_reg, 4);
280                 charge_now_adc = get_unaligned_be32(bulk_reg);
281                 if (charge_now_adc < 0)
282                         return charge_now_adc;
283                 charge_now = ADC_TO_CHARGE_UAH(charge_now_adc,
284                                                charger->res_div);
285
286                 /*
287                  * Re-init columb counter with updated values to correct drift.
288                  */
289                 if (charge_now / 1000 > charger->fcc_mah) {
290                         dev_dbg(charger->dev,
291                                 "Recalibrating columb counter to %d uah\n",
292                                 charge_now);
293                         /*
294                          * Order of operations matters here to ensure we keep
295                          * enough precision until the last step to keep from
296                          * making needless updates to columb counter.
297                          */
298                         charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah,
299                                          charger->res_div);
300                         put_unaligned_be32(charge_now_adc, bulk_reg);
301                         regmap_bulk_write(rk808->regmap,
302                                           RK817_GAS_GAUGE_Q_INIT_H3,
303                                           bulk_reg, 4);
304                 }
305         }
306
307         /*
308          * Calibrate the fully charged capacity when we previously had a full
309          * battery (soc_cal = 1) and are now empty (at or below minimum design
310          * voltage). If our columb counter is still positive, subtract that
311          * from our fcc value to get a calibrated fcc, and if our columb
312          * counter is negative add that to our fcc (but not to exceed our
313          * design capacity).
314          */
315         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H,
316                          bulk_reg, 2);
317         tmp = get_unaligned_be16(bulk_reg);
318         volt_avg = (charger->voltage_k * tmp) + 1000 * charger->voltage_b;
319         if (volt_avg <= charger->bat_voltage_min_design_uv &&
320             charger->soc_cal) {
321                 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
322                                  bulk_reg, 4);
323                 charge_now_adc = get_unaligned_be32(bulk_reg);
324                 charge_now = ADC_TO_CHARGE_UAH(charge_now_adc,
325                                                charger->res_div);
326                 /*
327                  * Note, if charge_now is negative this will add it (what we
328                  * want) and if it's positive this will subtract (also what
329                  * we want).
330                  */
331                 charger->fcc_mah = charger->fcc_mah - (charge_now / 1000);
332
333                 dev_dbg(charger->dev,
334                         "Recalibrating full charge capacity to %d uah\n",
335                         charger->fcc_mah * 1000);
336         }
337
338         /*
339          * Set the SOC to 0 if we are below the minimum system voltage.
340          */
341         if (volt_avg <= charger->bat_voltage_min_design_uv) {
342                 charger->soc = 0;
343                 charge_now_adc = CHARGE_TO_ADC(0, charger->res_div);
344                 put_unaligned_be32(charge_now_adc, bulk_reg);
345                 regmap_bulk_write(rk808->regmap,
346                                   RK817_GAS_GAUGE_Q_INIT_H3, bulk_reg, 4);
347                 dev_warn(charger->dev,
348                          "Battery voltage %d below minimum voltage %d\n",
349                          volt_avg, charger->bat_voltage_min_design_uv);
350                 }
351
352         rk817_record_battery_nvram_values(charger);
353
354         return 0;
355 }
356
357 static void rk817_read_props(struct rk817_charger *charger)
358 {
359         int tmp, reg;
360         u8 bulk_reg[4];
361
362         /*
363          * Recalibrate voltage and current readings if we need to BSP does both
364          * on CUR_CALIB_UPD, ignoring VOL_CALIB_UPD. Curiously enough, both
365          * documentation and the BSP show that you perform an update if bit 7
366          * is 1, but you clear the status by writing a 1 to bit 7.
367          */
368         regmap_read(charger->rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG1, &reg);
369         if (reg & RK817_VOL_CUR_CALIB_UPD) {
370                 rk817_bat_calib_cur(charger);
371                 rk817_bat_calib_vol(charger);
372                 regmap_write_bits(charger->rk808->regmap,
373                                   RK817_GAS_GAUGE_ADC_CONFIG1,
374                                   RK817_VOL_CUR_CALIB_UPD,
375                                   RK817_VOL_CUR_CALIB_UPD);
376         }
377
378         /* Update reported charge. */
379         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
380                          bulk_reg, 4);
381         tmp = get_unaligned_be32(bulk_reg);
382         charger->charge_now_uah = ADC_TO_CHARGE_UAH(tmp, charger->res_div);
383         if (charger->charge_now_uah < 0)
384                 charger->charge_now_uah = 0;
385         if (charger->charge_now_uah > charger->fcc_mah * 1000)
386                 charger->charge_now_uah = charger->fcc_mah * 1000;
387
388         /* Update soc based on reported charge. */
389         charger->soc = charger->charge_now_uah * 100 / charger->fcc_mah;
390
391         /* Update reported voltage. */
392         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H,
393                          bulk_reg, 2);
394         tmp = get_unaligned_be16(bulk_reg);
395         charger->volt_avg_uv = (charger->voltage_k * tmp) + 1000 *
396                                 charger->voltage_b;
397
398         /*
399          * Update reported current. Note value from registers is a signed 16
400          * bit int.
401          */
402         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_CUR_H,
403                          bulk_reg, 2);
404         tmp = (short int)get_unaligned_be16(bulk_reg);
405         charger->cur_avg_ua = ADC_TO_CURRENT(tmp, charger->res_div);
406
407         /*
408          * Update the max charge current. This value shouldn't change, but we
409          * can read it to report what the PMIC says it is instead of simply
410          * returning the default value.
411          */
412         regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, &reg);
413         charger->max_chg_cur_ua =
414                 rk817_chg_cur_from_reg(reg & RK817_CHRG_CUR_SEL);
415
416         /*
417          * Update max charge voltage. Like the max charge current this value
418          * shouldn't change, but we can report what the PMIC says.
419          */
420         regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, &reg);
421         charger->max_chg_volt_uv = ((((reg & RK817_CHRG_VOL_SEL) >> 4) *
422                                     50000) + 4100000);
423
424         /* Check if battery still present. */
425         regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, &reg);
426         charger->battery_present = (reg & RK817_BAT_EXS);
427
428         /* Get which type of charge we are using (if any). */
429         regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, &reg);
430         charger->charge_status = (reg >> 4) & 0x07;
431
432         /*
433          * Get charger input voltage. Note that on my example hardware (an
434          * Odroid Go Advance) the voltage of the power connector is measured
435          * on the register labelled USB in the datasheet; I don't know if this
436          * is how it is designed or just a quirk of the implementation. I
437          * believe this will also measure the voltage of the USB output when in
438          * OTG mode, if that is the case we may need to change this in the
439          * future to return 0 if the power supply status is offline (I can't
440          * test this with my current implementation. Also, when the voltage
441          * should be zero sometimes the ADC still shows a single bit (which
442          * would register as 20000uv). When this happens set it to 0.
443          */
444         regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_USB_VOL_H,
445                          bulk_reg, 2);
446         reg = get_unaligned_be16(bulk_reg);
447         if (reg > 1) {
448                 tmp = ((charger->voltage_k * reg / 1000 + charger->voltage_b) *
449                        60 / 46);
450                 charger->charger_input_volt_avg_uv = tmp * 1000;
451         } else {
452                 charger->charger_input_volt_avg_uv = 0;
453         }
454
455         /* Calibrate battery capacity and soc. */
456         rk817_bat_calib_cap(charger);
457 }
458
459 static int rk817_bat_get_prop(struct power_supply *ps,
460                 enum power_supply_property prop,
461                 union power_supply_propval *val)
462 {
463         struct rk817_charger *charger = power_supply_get_drvdata(ps);
464
465         switch (prop) {
466         case POWER_SUPPLY_PROP_PRESENT:
467                 val->intval = charger->battery_present;
468                 break;
469         case POWER_SUPPLY_PROP_STATUS:
470                 if (charger->cur_avg_ua < 0) {
471                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
472                         break;
473                 }
474                 switch (charger->charge_status) {
475                 case CHRG_OFF:
476                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
477                         break;
478                 /*
479                  * Dead charge is documented, but not explained. I never
480                  * observed it but assume it's a pre-charge for a dead
481                  * battery.
482                  */
483                 case DEAD_CHRG:
484                 case TRICKLE_CHRG:
485                 case CC_OR_CV_CHRG:
486                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
487                         break;
488                 case CHARGE_FINISH:
489                         val->intval = POWER_SUPPLY_STATUS_FULL;
490                         break;
491                 default:
492                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
493                         return -EINVAL;
494
495                 }
496                 break;
497         case POWER_SUPPLY_PROP_CHARGE_TYPE:
498                 switch (charger->charge_status) {
499                 case CHRG_OFF:
500                 case CHARGE_FINISH:
501                         val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
502                         break;
503                 case TRICKLE_CHRG:
504                         val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
505                         break;
506                 case DEAD_CHRG:
507                 case CC_OR_CV_CHRG:
508                         val->intval = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
509                         break;
510                 default:
511                         val->intval = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
512                         break;
513                 }
514                 break;
515         case POWER_SUPPLY_PROP_CHARGE_FULL:
516                 val->intval = charger->fcc_mah * 1000;
517                 break;
518         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
519                 val->intval = charger->bat_charge_full_design_uah;
520                 break;
521         case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
522                 val->intval = 0;
523                 break;
524         case POWER_SUPPLY_PROP_CHARGE_NOW:
525                 val->intval = charger->charge_now_uah;
526                 break;
527         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
528                 val->intval = charger->bat_voltage_min_design_uv;
529                 break;
530         case POWER_SUPPLY_PROP_CAPACITY:
531                 /* Add 500 so that values like 99999 are 100% not 99%. */
532                 val->intval = (charger->soc + 500) / 1000;
533                 if (val->intval > 100)
534                         val->intval = 100;
535                 if (val->intval < 0)
536                         val->intval = 0;
537                 break;
538         case POWER_SUPPLY_PROP_VOLTAGE_AVG:
539                 val->intval = charger->volt_avg_uv;
540                 break;
541         case POWER_SUPPLY_PROP_CURRENT_AVG:
542                 val->intval = charger->cur_avg_ua;
543                 break;
544         case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
545                 val->intval = charger->max_chg_cur_ua;
546                 break;
547         case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
548                 val->intval = charger->max_chg_volt_uv;
549                 break;
550         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
551                 val->intval = charger->bat_voltage_max_design_uv;
552                 break;
553         default:
554                 return -EINVAL;
555         }
556         return 0;
557 }
558
559 static int rk817_chg_get_prop(struct power_supply *ps,
560                               enum power_supply_property prop,
561                               union power_supply_propval *val)
562 {
563         struct rk817_charger *charger = power_supply_get_drvdata(ps);
564
565         switch (prop) {
566         case POWER_SUPPLY_PROP_ONLINE:
567                 val->intval = charger->plugged_in;
568                 break;
569         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
570                 /* max voltage from datasheet at 5.5v (default 5.0v) */
571                 val->intval = 5500000;
572                 break;
573         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
574                 /* min voltage from datasheet at 3.8v (default 5.0v) */
575                 val->intval = 3800000;
576                 break;
577         case POWER_SUPPLY_PROP_VOLTAGE_AVG:
578                 val->intval = charger->charger_input_volt_avg_uv;
579                 break;
580         /*
581          * While it's possible that other implementations could use different
582          * USB types, the current implementation for this PMIC (the Odroid Go
583          * Advance) only uses a dedicated charging port with no rx/tx lines.
584          */
585         case POWER_SUPPLY_PROP_USB_TYPE:
586                 val->intval = POWER_SUPPLY_USB_TYPE_DCP;
587                 break;
588         default:
589                 return -EINVAL;
590         }
591         return 0;
592
593 }
594
595 static irqreturn_t rk817_plug_in_isr(int irq, void *cg)
596 {
597         struct rk817_charger *charger;
598
599         charger = (struct rk817_charger *)cg;
600         charger->plugged_in = 1;
601         power_supply_changed(charger->chg_ps);
602         power_supply_changed(charger->bat_ps);
603         /* try to recalibrate capacity if we hit full charge. */
604         charger->soc_cal = 0;
605
606         rk817_read_props(charger);
607
608         dev_dbg(charger->dev, "Power Cord Inserted\n");
609
610         return IRQ_HANDLED;
611 }
612
613 static irqreturn_t rk817_plug_out_isr(int irq, void *cg)
614 {
615         struct rk817_charger *charger;
616         struct rk808 *rk808;
617
618         charger = (struct rk817_charger *)cg;
619         rk808 = charger->rk808;
620         charger->plugged_in = 0;
621         power_supply_changed(charger->bat_ps);
622         power_supply_changed(charger->chg_ps);
623
624         /*
625          * For some reason the bits of RK817_PMIC_CHRG_IN reset whenever the
626          * power cord is unplugged. This was not documented in the BSP kernel
627          * or the datasheet and only discovered by trial and error. Set minimum
628          * USB input voltage to 4.5v and enable USB voltage input limit.
629          */
630         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
631                           RK817_USB_VLIM_SEL, (0x05 << 4));
632         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN,
633                           (0x01 << 7));
634
635         /*
636          * Set average USB input current limit to 1.5A and enable USB current
637          * input limit.
638          */
639         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
640                           RK817_USB_ILIM_SEL, 0x03);
641         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN,
642                           (0x01 << 3));
643
644         rk817_read_props(charger);
645
646         dev_dbg(charger->dev, "Power Cord Removed\n");
647
648         return IRQ_HANDLED;
649 }
650
651 static enum power_supply_property rk817_bat_props[] = {
652         POWER_SUPPLY_PROP_PRESENT,
653         POWER_SUPPLY_PROP_STATUS,
654         POWER_SUPPLY_PROP_CHARGE_TYPE,
655         POWER_SUPPLY_PROP_CHARGE_FULL,
656         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
657         POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
658         POWER_SUPPLY_PROP_CHARGE_NOW,
659         POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
660         POWER_SUPPLY_PROP_VOLTAGE_AVG,
661         POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
662         POWER_SUPPLY_PROP_CURRENT_AVG,
663         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
664         POWER_SUPPLY_PROP_CAPACITY,
665         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
666 };
667
668 static enum power_supply_property rk817_chg_props[] = {
669         POWER_SUPPLY_PROP_ONLINE,
670         POWER_SUPPLY_PROP_USB_TYPE,
671         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
672         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
673         POWER_SUPPLY_PROP_VOLTAGE_AVG,
674 };
675
676 static enum power_supply_usb_type rk817_usb_type[] = {
677         POWER_SUPPLY_USB_TYPE_DCP,
678         POWER_SUPPLY_USB_TYPE_UNKNOWN,
679 };
680
681 static const struct power_supply_desc rk817_bat_desc = {
682         .name = "rk817-battery",
683         .type = POWER_SUPPLY_TYPE_BATTERY,
684         .properties = rk817_bat_props,
685         .num_properties = ARRAY_SIZE(rk817_bat_props),
686         .get_property = rk817_bat_get_prop,
687 };
688
689 static const struct power_supply_desc rk817_chg_desc = {
690         .name = "rk817-charger",
691         .type = POWER_SUPPLY_TYPE_USB,
692         .usb_types = rk817_usb_type,
693         .num_usb_types = ARRAY_SIZE(rk817_usb_type),
694         .properties = rk817_chg_props,
695         .num_properties = ARRAY_SIZE(rk817_chg_props),
696         .get_property = rk817_chg_get_prop,
697 };
698
699 static int rk817_read_battery_nvram_values(struct rk817_charger *charger)
700 {
701         u8 bulk_reg[3];
702         int ret;
703
704         /* Read the nvram data for full charge capacity. */
705         ret = regmap_bulk_read(charger->rk808->regmap,
706                                RK817_GAS_GAUGE_DATA3, bulk_reg, 3);
707         if (ret < 0)
708                 return ret;
709         charger->fcc_mah = get_unaligned_le24(bulk_reg);
710
711         /*
712          * Sanity checking for values equal to zero or less than would be
713          * practical for this device (BSP Kernel assumes 500mAH or less) for
714          * practicality purposes. Also check if the value is too large and
715          * correct it.
716          */
717         if ((charger->fcc_mah < 500) ||
718            ((charger->fcc_mah * 1000) > charger->bat_charge_full_design_uah)) {
719                 dev_info(charger->dev,
720                          "Invalid NVRAM max charge, setting to %u uAH\n",
721                          charger->bat_charge_full_design_uah);
722                 charger->fcc_mah = charger->bat_charge_full_design_uah / 1000;
723         }
724
725         /*
726          * Read the nvram for state of charge. Sanity check for values greater
727          * than 100 (10000) or less than 0, because other things (BSP kernels,
728          * U-Boot, or even i2cset) can write to this register. If the value is
729          * off it should get corrected automatically when the voltage drops to
730          * the min (soc is 0) or when the battery is full (soc is 100).
731          */
732         ret = regmap_bulk_read(charger->rk808->regmap,
733                                RK817_GAS_GAUGE_BAT_R1, bulk_reg, 3);
734         if (ret < 0)
735                 return ret;
736         charger->soc = get_unaligned_le24(bulk_reg);
737         if (charger->soc > 10000)
738                 charger->soc = 10000;
739         if (charger->soc < 0)
740                 charger->soc = 0;
741
742         return 0;
743 }
744
745 static int
746 rk817_read_or_set_full_charge_on_boot(struct rk817_charger *charger,
747                                 struct power_supply_battery_info *bat_info)
748 {
749         struct rk808 *rk808 = charger->rk808;
750         u8 bulk_reg[4];
751         u32 boot_voltage, boot_charge_mah;
752         int ret, reg, off_time, tmp;
753         bool first_boot;
754
755         /*
756          * Check if the battery is uninitalized. If it is, the columb counter
757          * needs to be set up.
758          */
759         ret = regmap_read(rk808->regmap, RK817_GAS_GAUGE_GG_STS, &reg);
760         if (ret < 0)
761                 return ret;
762         first_boot = reg & RK817_BAT_CON;
763         /*
764          * If the battery is uninitialized, use the poweron voltage and an ocv
765          * lookup to guess our charge. The number won't be very accurate until
766          * we hit either our minimum voltage (0%) or full charge (100%).
767          */
768         if (first_boot) {
769                 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_PWRON_VOL_H,
770                                  bulk_reg, 2);
771                 tmp = get_unaligned_be16(bulk_reg);
772                 boot_voltage = (charger->voltage_k * tmp) +
773                                 1000 * charger->voltage_b;
774                 /*
775                  * Since only implementation has no working thermistor, assume
776                  * 20C for OCV lookup. If lookup fails, report error with OCV
777                  * table.
778                  */
779                 charger->soc = power_supply_batinfo_ocv2cap(bat_info,
780                                                             boot_voltage,
781                                                             20) * 1000;
782                 if (charger->soc < 0)
783                         charger->soc = 0;
784
785                 /* Guess that full charge capacity is the design capacity */
786                 charger->fcc_mah = charger->bat_charge_full_design_uah / 1000;
787                 /*
788                  * Set battery as "set up". BSP driver uses this value even
789                  * though datasheet claims it's a read-only value.
790                  */
791                 regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS,
792                                   RK817_BAT_CON, 0);
793                 /* Save nvram values */
794                 ret = rk817_record_battery_nvram_values(charger);
795                 if (ret < 0)
796                         return ret;
797         } else {
798                 ret = rk817_read_battery_nvram_values(charger);
799                 if (ret < 0)
800                         return ret;
801
802                 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
803                                  bulk_reg, 4);
804                 tmp = get_unaligned_be32(bulk_reg);
805                 if (tmp < 0)
806                         tmp = 0;
807                 boot_charge_mah = ADC_TO_CHARGE_UAH(tmp,
808                                                     charger->res_div) / 1000;
809                 /*
810                  * Check if the columb counter has been off for more than 30
811                  * minutes as it tends to drift downward. If so, re-init soc
812                  * with the boot voltage instead. Note the unit values for the
813                  * OFF_CNT register appear to be in decaminutes and stops
814                  * counting at 2550 (0xFF) minutes. BSP kernel used OCV, but
815                  * for me occasionally that would show invalid values. Boot
816                  * voltage is only accurate for me on first poweron (not
817                  * reboots), but we shouldn't ever encounter an OFF_CNT more
818                  * than 0 on a reboot anyway.
819                  */
820                 regmap_read(rk808->regmap, RK817_GAS_GAUGE_OFF_CNT, &off_time);
821                 if (off_time >= 3) {
822                         regmap_bulk_read(rk808->regmap,
823                                          RK817_GAS_GAUGE_PWRON_VOL_H,
824                                          bulk_reg, 2);
825                         tmp = get_unaligned_be16(bulk_reg);
826                         boot_voltage = (charger->voltage_k * tmp) +
827                                         1000 * charger->voltage_b;
828                         charger->soc =
829                                 power_supply_batinfo_ocv2cap(bat_info,
830                                                              boot_voltage,
831                                                              20) * 1000;
832                 } else {
833                         charger->soc = (boot_charge_mah * 1000 * 100 /
834                                         charger->fcc_mah);
835                 }
836         }
837
838         /*
839          * Now we have our full charge capacity and soc, init the columb
840          * counter.
841          */
842         boot_charge_mah = charger->soc * charger->fcc_mah / 100 / 1000;
843         if (boot_charge_mah > charger->fcc_mah)
844                 boot_charge_mah = charger->fcc_mah;
845         tmp = CHARGE_TO_ADC(boot_charge_mah, charger->res_div);
846         put_unaligned_be32(tmp, bulk_reg);
847         ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3,
848                           bulk_reg, 4);
849         if (ret < 0)
850                 return ret;
851
852         /* Set QMAX value to max design capacity. */
853         tmp = CHARGE_TO_ADC((charger->bat_charge_full_design_uah / 1000),
854                             charger->res_div);
855         put_unaligned_be32(tmp, bulk_reg);
856         ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_MAX_H3,
857                                 bulk_reg, 4);
858         if (ret < 0)
859                 return ret;
860
861         return 0;
862 }
863
864 static int rk817_battery_init(struct rk817_charger *charger,
865                               struct power_supply_battery_info *bat_info)
866 {
867         struct rk808 *rk808 = charger->rk808;
868         u32 tmp, max_chg_vol_mv, max_chg_cur_ma;
869         u8 max_chg_vol_reg, chg_term_i_reg;
870         int ret, chg_term_ma, max_chg_cur_reg;
871         u8 bulk_reg[2];
872
873         /* Get initial plug state */
874         regmap_read(rk808->regmap, RK817_SYS_STS, &tmp);
875         charger->plugged_in = (tmp & RK817_PLUG_IN_STS);
876
877         /*
878          * Turn on all ADC functions to measure battery, USB, and sys voltage,
879          * as well as batt temp. Note only tested implementation so far does
880          * not use a battery with a thermistor.
881          */
882         regmap_write(rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG0, 0xfc);
883
884         /*
885          * Set relax mode voltage sampling interval and ADC offset calibration
886          * interval to 8 minutes to mirror BSP kernel. Set voltage and current
887          * modes to average to mirror BSP kernel.
888          */
889         regmap_write(rk808->regmap, RK817_GAS_GAUGE_GG_CON, 0x04);
890
891         /* Calibrate voltage like the BSP does here. */
892         rk817_bat_calib_vol(charger);
893
894         /* Write relax threshold, derived from sleep enter current. */
895         tmp = CURRENT_TO_ADC(charger->sleep_enter_current_ua,
896                              charger->res_div);
897         put_unaligned_be16(tmp, bulk_reg);
898         regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_RELAX_THRE_H,
899                           bulk_reg, 2);
900
901         /* Write sleep sample current, derived from sleep filter current. */
902         tmp = CURRENT_TO_ADC(charger->sleep_filter_current_ua,
903                              charger->res_div);
904         put_unaligned_be16(tmp, bulk_reg);
905         regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_SLEEP_CON_SAMP_CUR_H,
906                           bulk_reg, 2);
907
908         /* Restart battery relax voltage */
909         regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS,
910                           RK817_RELAX_VOL_UPD, (0x0 << 2));
911
912         /*
913          * Set OCV Threshold Voltage to 127.5mV. This was hard coded like this
914          * in the BSP.
915          */
916         regmap_write(rk808->regmap, RK817_GAS_GAUGE_OCV_THRE_VOL, 0xff);
917
918         /*
919          * Set maximum charging voltage to battery max voltage. Trying to be
920          * incredibly safe with these value, as setting them wrong could
921          * overcharge the battery, which would be very bad.
922          */
923         max_chg_vol_mv = bat_info->constant_charge_voltage_max_uv / 1000;
924         max_chg_cur_ma = bat_info->constant_charge_current_max_ua / 1000;
925
926         if (max_chg_vol_mv < 4100) {
927                 return dev_err_probe(charger->dev, -EINVAL,
928                        "invalid max charger voltage, value %u unsupported\n",
929                         max_chg_vol_mv * 1000);
930         }
931         if (max_chg_vol_mv > 4450) {
932                 dev_info(charger->dev,
933                          "Setting max charge voltage to 4450000uv\n");
934                 max_chg_vol_mv = 4450;
935         }
936
937         if (max_chg_cur_ma < 500) {
938                 return dev_err_probe(charger->dev, -EINVAL,
939                        "invalid max charger current, value %u unsupported\n",
940                        max_chg_cur_ma * 1000);
941         }
942         if (max_chg_cur_ma > 3500)
943                 dev_info(charger->dev,
944                          "Setting max charge current to 3500000ua\n");
945
946         /*
947          * Now that the values are sanity checked, if we subtract 4100 from the
948          * max voltage and divide by 50, we conviently get the exact value for
949          * the registers, which are 4.1v, 4.15v, 4.2v, 4.25v, 4.3v, 4.35v,
950          * 4.4v, and 4.45v; these correspond to values 0x00 through 0x07.
951          */
952         max_chg_vol_reg = (max_chg_vol_mv - 4100) / 50;
953
954         max_chg_cur_reg = rk817_chg_cur_to_reg(max_chg_cur_ma);
955
956         if (max_chg_vol_reg < 0 || max_chg_vol_reg > 7) {
957                 return dev_err_probe(charger->dev, -EINVAL,
958                        "invalid max charger voltage, value %u unsupported\n",
959                        max_chg_vol_mv * 1000);
960         }
961         if (max_chg_cur_reg < 0 || max_chg_cur_reg > 7) {
962                 return dev_err_probe(charger->dev, -EINVAL,
963                        "invalid max charger current, value %u unsupported\n",
964                        max_chg_cur_ma * 1000);
965         }
966
967         /*
968          * Write the values to the registers, and deliver an emergency warning
969          * in the event they are not written correctly.
970          */
971         ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT,
972                                 RK817_CHRG_VOL_SEL, (max_chg_vol_reg << 4));
973         if (ret) {
974                 dev_emerg(charger->dev,
975                           "Danger, unable to set max charger voltage: %u\n",
976                           ret);
977         }
978
979         ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT,
980                                 RK817_CHRG_CUR_SEL, max_chg_cur_reg);
981         if (ret) {
982                 dev_emerg(charger->dev,
983                           "Danger, unable to set max charger current: %u\n",
984                           ret);
985         }
986
987         /* Set charge finishing mode to analog */
988         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM,
989                           RK817_CHRG_TERM_ANA_DIG, (0x0 << 2));
990
991         /*
992          * Set charge finish current, warn if value not in range and keep
993          * default.
994          */
995         chg_term_ma = bat_info->charge_term_current_ua / 1000;
996         if (chg_term_ma < 150 || chg_term_ma > 400) {
997                 dev_warn(charger->dev,
998                          "Invalid charge termination %u, keeping default\n",
999                          chg_term_ma * 1000);
1000                 chg_term_ma = 200;
1001         }
1002
1003         /*
1004          * Values of 150ma, 200ma, 300ma, and 400ma correspond to 00, 01, 10,
1005          * and 11.
1006          */
1007         chg_term_i_reg = (chg_term_ma - 100) / 100;
1008         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM,
1009                           RK817_CHRG_TERM_ANA_SEL, chg_term_i_reg);
1010
1011         ret = rk817_read_or_set_full_charge_on_boot(charger, bat_info);
1012         if (ret < 0)
1013                 return ret;
1014
1015         /*
1016          * Set minimum USB input voltage to 4.5v and enable USB voltage input
1017          * limit.
1018          */
1019         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
1020                           RK817_USB_VLIM_SEL, (0x05 << 4));
1021         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN,
1022                           (0x01 << 7));
1023
1024         /*
1025          * Set average USB input current limit to 1.5A and enable USB current
1026          * input limit.
1027          */
1028         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
1029                           RK817_USB_ILIM_SEL, 0x03);
1030         regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN,
1031                           (0x01 << 3));
1032
1033         return 0;
1034 }
1035
1036 static void rk817_charging_monitor(struct work_struct *work)
1037 {
1038         struct rk817_charger *charger;
1039
1040         charger = container_of(work, struct rk817_charger, work.work);
1041
1042         rk817_read_props(charger);
1043
1044         /* Run every 8 seconds like the BSP driver did. */
1045         queue_delayed_work(system_wq, &charger->work, msecs_to_jiffies(8000));
1046 }
1047
1048 static int rk817_charger_probe(struct platform_device *pdev)
1049 {
1050         struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
1051         struct rk817_charger *charger;
1052         struct device_node *node;
1053         struct power_supply_battery_info *bat_info;
1054         struct device *dev = &pdev->dev;
1055         struct power_supply_config pscfg = {};
1056         int plugin_irq, plugout_irq;
1057         int of_value;
1058         int ret;
1059
1060         node = of_get_child_by_name(dev->parent->of_node, "charger");
1061         if (!node)
1062                 return -ENODEV;
1063
1064         charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
1065         if (!charger) {
1066                 of_node_put(node);
1067                 return -ENOMEM;
1068         }
1069
1070         charger->rk808 = rk808;
1071
1072         charger->dev = &pdev->dev;
1073         platform_set_drvdata(pdev, charger);
1074
1075         rk817_bat_calib_vol(charger);
1076
1077         pscfg.drv_data = charger;
1078         pscfg.of_node = node;
1079
1080         /*
1081          * Get sample resistor value. Note only values of 10000 or 20000
1082          * microohms are allowed. Schematic for my test implementation (an
1083          * Odroid Go Advance) shows a 10 milliohm resistor for reference.
1084          */
1085         ret = of_property_read_u32(node, "rockchip,resistor-sense-micro-ohms",
1086                                    &of_value);
1087         if (ret < 0) {
1088                 return dev_err_probe(dev, ret,
1089                                      "Error reading sample resistor value\n");
1090         }
1091         /*
1092          * Store as a 1 or a 2, since all we really use the value for is as a
1093          * divisor in some calculations.
1094          */
1095         charger->res_div = (of_value == 20000) ? 2 : 1;
1096
1097         /*
1098          * Get sleep enter current value. Not sure what this value is for
1099          * other than to help calibrate the relax threshold.
1100          */
1101         ret = of_property_read_u32(node,
1102                                    "rockchip,sleep-enter-current-microamp",
1103                                    &of_value);
1104         if (ret < 0) {
1105                 return dev_err_probe(dev, ret,
1106                                      "Error reading sleep enter cur value\n");
1107         }
1108         charger->sleep_enter_current_ua = of_value;
1109
1110         /* Get sleep filter current value */
1111         ret = of_property_read_u32(node,
1112                                    "rockchip,sleep-filter-current-microamp",
1113                                    &of_value);
1114         if (ret < 0) {
1115                 return dev_err_probe(dev, ret,
1116                                      "Error reading sleep filter cur value\n");
1117         }
1118
1119         charger->sleep_filter_current_ua = of_value;
1120
1121         charger->bat_ps = devm_power_supply_register(&pdev->dev,
1122                                                      &rk817_bat_desc, &pscfg);
1123         if (IS_ERR(charger->bat_ps))
1124                 return dev_err_probe(dev, -EINVAL,
1125                                      "Battery failed to probe\n");
1126
1127         charger->chg_ps = devm_power_supply_register(&pdev->dev,
1128                                                      &rk817_chg_desc, &pscfg);
1129         if (IS_ERR(charger->chg_ps))
1130                 return dev_err_probe(dev, -EINVAL,
1131                                      "Charger failed to probe\n");
1132
1133         ret = power_supply_get_battery_info(charger->bat_ps,
1134                                             &bat_info);
1135         if (ret) {
1136                 return dev_err_probe(dev, ret,
1137                                      "Unable to get battery info\n");
1138         }
1139
1140         if ((bat_info->charge_full_design_uah <= 0) ||
1141             (bat_info->voltage_min_design_uv <= 0) ||
1142             (bat_info->voltage_max_design_uv <= 0) ||
1143             (bat_info->constant_charge_voltage_max_uv <= 0) ||
1144             (bat_info->constant_charge_current_max_ua <= 0) ||
1145             (bat_info->charge_term_current_ua <= 0)) {
1146                 return dev_err_probe(dev, -EINVAL,
1147                                      "Required bat info missing or invalid\n");
1148         }
1149
1150         charger->bat_charge_full_design_uah = bat_info->charge_full_design_uah;
1151         charger->bat_voltage_min_design_uv = bat_info->voltage_min_design_uv;
1152         charger->bat_voltage_max_design_uv = bat_info->voltage_max_design_uv;
1153
1154         /*
1155          * Has to run after power_supply_get_battery_info as it depends on some
1156          * values discovered from that routine.
1157          */
1158         ret = rk817_battery_init(charger, bat_info);
1159         if (ret)
1160                 return ret;
1161
1162         power_supply_put_battery_info(charger->bat_ps, bat_info);
1163
1164         plugin_irq = platform_get_irq(pdev, 0);
1165         if (plugin_irq < 0)
1166                 return plugin_irq;
1167
1168         plugout_irq = platform_get_irq(pdev, 1);
1169         if (plugout_irq < 0)
1170                 return plugout_irq;
1171
1172         ret = devm_request_threaded_irq(charger->dev, plugin_irq, NULL,
1173                                         rk817_plug_in_isr,
1174                                         IRQF_TRIGGER_RISING | IRQF_ONESHOT,
1175                                         "rk817_plug_in", charger);
1176         if (ret) {
1177                 return dev_err_probe(&pdev->dev, ret,
1178                                       "plug_in_irq request failed!\n");
1179         }
1180
1181         ret = devm_request_threaded_irq(charger->dev, plugout_irq, NULL,
1182                                         rk817_plug_out_isr,
1183                                         IRQF_TRIGGER_RISING | IRQF_ONESHOT,
1184                                         "rk817_plug_out", charger);
1185         if (ret) {
1186                 return dev_err_probe(&pdev->dev, ret,
1187                                      "plug_out_irq request failed!\n");
1188         }
1189
1190         ret = devm_delayed_work_autocancel(&pdev->dev, &charger->work,
1191                                            rk817_charging_monitor);
1192         if (ret)
1193                 return ret;
1194
1195         /* Force the first update immediately. */
1196         mod_delayed_work(system_wq, &charger->work, 0);
1197
1198         return 0;
1199 }
1200
1201
1202 static struct platform_driver rk817_charger_driver = {
1203         .probe    = rk817_charger_probe,
1204         .driver   = {
1205                 .name  = "rk817-charger",
1206         },
1207 };
1208 module_platform_driver(rk817_charger_driver);
1209
1210 MODULE_DESCRIPTION("Battery power supply driver for RK817 PMIC");
1211 MODULE_AUTHOR("Maya Matuszczyk <maccraft123mc@gmail.com>");
1212 MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
1213 MODULE_LICENSE("GPL");