1 /*
2  * TWL4030/TPS65950 BCI (Battery Charger Interface) driver
3  *
4  * Copyright (C) 2010 Gražvydas Ignotas <notasas@gmail.com>
5  *
6  * based on twl4030_bci_battery.c by TI
7  * Copyright (C) 2008 Texas Instruments, Inc.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/err.h>
19 #include <linux/platform_device.h>
20 #include <linux/interrupt.h>
21 #include <linux/i2c/twl.h>
22 #include <linux/power_supply.h>
23 #include <linux/notifier.h>
24 #include <linux/usb/otg.h>
25 #include <linux/iio/consumer.h>
26 
27 #define TWL4030_BCIMDEN		0x00
28 #define TWL4030_BCIMDKEY	0x01
29 #define TWL4030_BCIMSTATEC	0x02
30 #define TWL4030_BCIICHG		0x08
31 #define TWL4030_BCIVAC		0x0a
32 #define TWL4030_BCIVBUS		0x0c
33 #define TWL4030_BCIMFSTS3	0x0F
34 #define TWL4030_BCIMFSTS4	0x10
35 #define TWL4030_BCICTL1		0x23
36 #define TWL4030_BB_CFG		0x12
37 #define TWL4030_BCIIREF1	0x27
38 #define TWL4030_BCIIREF2	0x28
39 #define TWL4030_BCIMFKEY	0x11
40 #define TWL4030_BCIMFEN3	0x14
41 #define TWL4030_BCIMFTH8	0x1d
42 #define TWL4030_BCIMFTH9	0x1e
43 #define TWL4030_BCIWDKEY	0x21
44 
45 #define TWL4030_BCIMFSTS1	0x01
46 
47 #define TWL4030_BCIAUTOWEN	BIT(5)
48 #define TWL4030_CONFIG_DONE	BIT(4)
49 #define TWL4030_CVENAC		BIT(2)
50 #define TWL4030_BCIAUTOUSB	BIT(1)
51 #define TWL4030_BCIAUTOAC	BIT(0)
52 #define TWL4030_CGAIN		BIT(5)
53 #define TWL4030_USBFASTMCHG	BIT(2)
54 #define TWL4030_STS_VBUS	BIT(7)
55 #define TWL4030_STS_USB_ID	BIT(2)
56 #define TWL4030_BBCHEN		BIT(4)
57 #define TWL4030_BBSEL_MASK	0x0c
58 #define TWL4030_BBSEL_2V5	0x00
59 #define TWL4030_BBSEL_3V0	0x04
60 #define TWL4030_BBSEL_3V1	0x08
61 #define TWL4030_BBSEL_3V2	0x0c
62 #define TWL4030_BBISEL_MASK	0x03
63 #define TWL4030_BBISEL_25uA	0x00
64 #define TWL4030_BBISEL_150uA	0x01
65 #define TWL4030_BBISEL_500uA	0x02
66 #define TWL4030_BBISEL_1000uA	0x03
67 
68 #define TWL4030_BATSTSPCHG	BIT(2)
69 #define TWL4030_BATSTSMCHG	BIT(6)
70 
71 /* BCI interrupts */
72 #define TWL4030_WOVF		BIT(0) /* Watchdog overflow */
73 #define TWL4030_TMOVF		BIT(1) /* Timer overflow */
74 #define TWL4030_ICHGHIGH	BIT(2) /* Battery charge current high */
75 #define TWL4030_ICHGLOW		BIT(3) /* Battery cc. low / FSM state change */
76 #define TWL4030_ICHGEOC		BIT(4) /* Battery current end-of-charge */
77 #define TWL4030_TBATOR2		BIT(5) /* Battery temperature out of range 2 */
78 #define TWL4030_TBATOR1		BIT(6) /* Battery temperature out of range 1 */
79 #define TWL4030_BATSTS		BIT(7) /* Battery status */
80 
81 #define TWL4030_VBATLVL		BIT(0) /* VBAT level */
82 #define TWL4030_VBATOV		BIT(1) /* VBAT overvoltage */
83 #define TWL4030_VBUSOV		BIT(2) /* VBUS overvoltage */
84 #define TWL4030_ACCHGOV		BIT(3) /* Ac charger overvoltage */
85 
86 #define TWL4030_MSTATEC_USB		BIT(4)
87 #define TWL4030_MSTATEC_AC		BIT(5)
88 #define TWL4030_MSTATEC_MASK		0x0f
89 #define TWL4030_MSTATEC_QUICK1		0x02
90 #define TWL4030_MSTATEC_QUICK7		0x07
91 #define TWL4030_MSTATEC_COMPLETE1	0x0b
92 #define TWL4030_MSTATEC_COMPLETE4	0x0e
93 
94 /*
95  * If AC (Accessory Charger) voltage exceeds 4.5V (MADC 11)
96  * then AC is available.
97  */
98 static inline int ac_available(struct iio_channel *channel_vac)
99 {
100 	int val, err;
101 
102 	if (!channel_vac)
103 		return 0;
104 
105 	err = iio_read_channel_processed(channel_vac, &val);
106 	if (err < 0)
107 		return 0;
108 	return val > 4500;
109 }
110 
111 static bool allow_usb;
112 module_param(allow_usb, bool, 0644);
113 MODULE_PARM_DESC(allow_usb, "Allow USB charge drawing default current");
114 
115 struct twl4030_bci {
116 	struct device		*dev;
117 	struct power_supply	*ac;
118 	struct power_supply	*usb;
119 	struct usb_phy		*transceiver;
120 	struct notifier_block	usb_nb;
121 	struct work_struct	work;
122 	int			irq_chg;
123 	int			irq_bci;
124 	int			usb_enabled;
125 
126 	/*
127 	 * ichg_* and *_cur values in uA. If any are 'large', we set
128 	 * CGAIN to '1' which doubles the range for half the
129 	 * precision.
130 	 */
131 	unsigned int		ichg_eoc, ichg_lo, ichg_hi;
132 	unsigned int		usb_cur, ac_cur;
133 	struct iio_channel	*channel_vac;
134 	bool			ac_is_active;
135 	int			usb_mode, ac_mode; /* charging mode requested */
136 #define	CHARGE_OFF	0
137 #define	CHARGE_AUTO	1
138 #define	CHARGE_LINEAR	2
139 
140 	/* When setting the USB current we slowly increase the
141 	 * requested current until target is reached or the voltage
142 	 * drops below 4.75V.  In the latter case we step back one
143 	 * step.
144 	 */
145 	unsigned int		usb_cur_target;
146 	struct delayed_work	current_worker;
147 #define	USB_CUR_STEP	20000	/* 20mA at a time */
148 #define	USB_MIN_VOLT	4750000	/* 4.75V */
149 #define	USB_CUR_DELAY	msecs_to_jiffies(100)
150 #define	USB_MAX_CURRENT	1700000 /* TWL4030 caps at 1.7A */
151 
152 	unsigned long		event;
153 };
154 
155 /* strings for 'usb_mode' values */
156 static char *modes[] = { "off", "auto", "continuous" };
157 
158 /*
159  * clear and set bits on an given register on a given module
160  */
161 static int twl4030_clear_set(u8 mod_no, u8 clear, u8 set, u8 reg)
162 {
163 	u8 val = 0;
164 	int ret;
165 
166 	ret = twl_i2c_read_u8(mod_no, &val, reg);
167 	if (ret)
168 		return ret;
169 
170 	val &= ~clear;
171 	val |= set;
172 
173 	return twl_i2c_write_u8(mod_no, val, reg);
174 }
175 
176 static int twl4030_bci_read(u8 reg, u8 *val)
177 {
178 	return twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, val, reg);
179 }
180 
181 static int twl4030_clear_set_boot_bci(u8 clear, u8 set)
182 {
183 	return twl4030_clear_set(TWL_MODULE_PM_MASTER, clear,
184 			TWL4030_CONFIG_DONE | TWL4030_BCIAUTOWEN | set,
185 			TWL4030_PM_MASTER_BOOT_BCI);
186 }
187 
188 static int twl4030bci_read_adc_val(u8 reg)
189 {
190 	int ret, temp;
191 	u8 val;
192 
193 	/* read MSB */
194 	ret = twl4030_bci_read(reg + 1, &val);
195 	if (ret)
196 		return ret;
197 
198 	temp = (int)(val & 0x03) << 8;
199 
200 	/* read LSB */
201 	ret = twl4030_bci_read(reg, &val);
202 	if (ret)
203 		return ret;
204 
205 	return temp | val;
206 }
207 
208 /*
209  * TI provided formulas:
210  * CGAIN == 0: ICHG = (BCIICHG * 1.7) / (2^10 - 1) - 0.85
211  * CGAIN == 1: ICHG = (BCIICHG * 3.4) / (2^10 - 1) - 1.7
212  * Here we use integer approximation of:
213  * CGAIN == 0: val * 1.6618 - 0.85 * 1000
214  * CGAIN == 1: (val * 1.6618 - 0.85 * 1000) * 2
215  */
216 /*
217  * convert twl register value for currents into uA
218  */
219 static int regval2ua(int regval, bool cgain)
220 {
221 	if (cgain)
222 		return (regval * 16618 - 8500 * 1000) / 5;
223 	else
224 		return (regval * 16618 - 8500 * 1000) / 10;
225 }
226 
227 /*
228  * convert uA currents into twl register value
229  */
230 static int ua2regval(int ua, bool cgain)
231 {
232 	int ret;
233 	if (cgain)
234 		ua /= 2;
235 	ret = (ua * 10 + 8500 * 1000) / 16618;
236 	/* rounding problems */
237 	if (ret < 512)
238 		ret = 512;
239 	return ret;
240 }
241 
242 static int twl4030_charger_update_current(struct twl4030_bci *bci)
243 {
244 	int status;
245 	int cur;
246 	unsigned reg, cur_reg;
247 	u8 bcictl1, oldreg, fullreg;
248 	bool cgain = false;
249 	u8 boot_bci;
250 
251 	/*
252 	 * If AC (Accessory Charger) voltage exceeds 4.5V (MADC 11)
253 	 * and AC is enabled, set current for 'ac'
254 	 */
255 	if (ac_available(bci->channel_vac)) {
256 		cur = bci->ac_cur;
257 		bci->ac_is_active = true;
258 	} else {
259 		cur = bci->usb_cur;
260 		bci->ac_is_active = false;
261 		if (cur > bci->usb_cur_target) {
262 			cur = bci->usb_cur_target;
263 			bci->usb_cur = cur;
264 		}
265 		if (cur < bci->usb_cur_target)
266 			schedule_delayed_work(&bci->current_worker, USB_CUR_DELAY);
267 	}
268 
269 	/* First, check thresholds and see if cgain is needed */
270 	if (bci->ichg_eoc >= 200000)
271 		cgain = true;
272 	if (bci->ichg_lo >= 400000)
273 		cgain = true;
274 	if (bci->ichg_hi >= 820000)
275 		cgain = true;
276 	if (cur > 852000)
277 		cgain = true;
278 
279 	status = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1);
280 	if (status < 0)
281 		return status;
282 	if (twl_i2c_read_u8(TWL_MODULE_PM_MASTER, &boot_bci,
283 			    TWL4030_PM_MASTER_BOOT_BCI) < 0)
284 		boot_bci = 0;
285 	boot_bci &= 7;
286 
287 	if ((!!cgain) != !!(bcictl1 & TWL4030_CGAIN))
288 		/* Need to turn for charging while we change the
289 		 * CGAIN bit.  Leave it off while everything is
290 		 * updated.
291 		 */
292 		twl4030_clear_set_boot_bci(boot_bci, 0);
293 
294 	/*
295 	 * For ichg_eoc, the hardware only supports reg values matching
296 	 * 100XXXX000, and requires the XXXX be stored in the high nibble
297 	 * of TWL4030_BCIMFTH8.
298 	 */
299 	reg = ua2regval(bci->ichg_eoc, cgain);
300 	if (reg > 0x278)
301 		reg = 0x278;
302 	if (reg < 0x200)
303 		reg = 0x200;
304 	reg = (reg >> 3) & 0xf;
305 	fullreg = reg << 4;
306 
307 	/*
308 	 * For ichg_lo, reg value must match 10XXXX0000.
309 	 * XXXX is stored in low nibble of TWL4030_BCIMFTH8.
310 	 */
311 	reg = ua2regval(bci->ichg_lo, cgain);
312 	if (reg > 0x2F0)
313 		reg = 0x2F0;
314 	if (reg < 0x200)
315 		reg = 0x200;
316 	reg = (reg >> 4) & 0xf;
317 	fullreg |= reg;
318 
319 	/* ichg_eoc and ichg_lo live in same register */
320 	status = twl4030_bci_read(TWL4030_BCIMFTH8, &oldreg);
321 	if (status < 0)
322 		return status;
323 	if (oldreg != fullreg) {
324 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xF4,
325 					  TWL4030_BCIMFKEY);
326 		if (status < 0)
327 			return status;
328 		twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
329 				 fullreg, TWL4030_BCIMFTH8);
330 	}
331 
332 	/* ichg_hi threshold must be 1XXXX01100 (I think) */
333 	reg = ua2regval(bci->ichg_hi, cgain);
334 	if (reg > 0x3E0)
335 		reg = 0x3E0;
336 	if (reg < 0x200)
337 		reg = 0x200;
338 	fullreg = (reg >> 5) & 0xF;
339 	fullreg <<= 4;
340 	status = twl4030_bci_read(TWL4030_BCIMFTH9, &oldreg);
341 	if (status < 0)
342 		return status;
343 	if ((oldreg & 0xF0) != fullreg) {
344 		fullreg |= (oldreg & 0x0F);
345 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xE7,
346 					  TWL4030_BCIMFKEY);
347 		if (status < 0)
348 			return status;
349 		twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
350 				 fullreg, TWL4030_BCIMFTH9);
351 	}
352 
353 	/*
354 	 * And finally, set the current.  This is stored in
355 	 * two registers.
356 	 */
357 	reg = ua2regval(cur, cgain);
358 	/* we have only 10 bits */
359 	if (reg > 0x3ff)
360 		reg = 0x3ff;
361 	status = twl4030_bci_read(TWL4030_BCIIREF1, &oldreg);
362 	if (status < 0)
363 		return status;
364 	cur_reg = oldreg;
365 	status = twl4030_bci_read(TWL4030_BCIIREF2, &oldreg);
366 	if (status < 0)
367 		return status;
368 	cur_reg |= oldreg << 8;
369 	if (reg != oldreg) {
370 		/* disable write protection for one write access for
371 		 * BCIIREF */
372 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xE7,
373 					  TWL4030_BCIMFKEY);
374 		if (status < 0)
375 			return status;
376 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
377 					  (reg & 0x100) ? 3 : 2,
378 					  TWL4030_BCIIREF2);
379 		if (status < 0)
380 			return status;
381 		/* disable write protection for one write access for
382 		 * BCIIREF */
383 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xE7,
384 					  TWL4030_BCIMFKEY);
385 		if (status < 0)
386 			return status;
387 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
388 					  reg & 0xff,
389 					  TWL4030_BCIIREF1);
390 	}
391 	if ((!!cgain) != !!(bcictl1 & TWL4030_CGAIN)) {
392 		/* Flip CGAIN and re-enable charging */
393 		bcictl1 ^= TWL4030_CGAIN;
394 		twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
395 				 bcictl1, TWL4030_BCICTL1);
396 		twl4030_clear_set_boot_bci(0, boot_bci);
397 	}
398 	return 0;
399 }
400 
401 static int twl4030_charger_get_current(void);
402 
403 static void twl4030_current_worker(struct work_struct *data)
404 {
405 	int v, curr;
406 	int res;
407 	struct twl4030_bci *bci = container_of(data, struct twl4030_bci,
408 					       current_worker.work);
409 
410 	res = twl4030bci_read_adc_val(TWL4030_BCIVBUS);
411 	if (res < 0)
412 		v = 0;
413 	else
414 		/* BCIVBUS uses ADCIN8, 7/1023 V/step */
415 		v = res * 6843;
416 	curr = twl4030_charger_get_current();
417 
418 	dev_dbg(bci->dev, "v=%d cur=%d limit=%d target=%d\n", v, curr,
419 		bci->usb_cur, bci->usb_cur_target);
420 
421 	if (v < USB_MIN_VOLT) {
422 		/* Back up and stop adjusting. */
423 		bci->usb_cur -= USB_CUR_STEP;
424 		bci->usb_cur_target = bci->usb_cur;
425 	} else if (bci->usb_cur >= bci->usb_cur_target ||
426 		   bci->usb_cur + USB_CUR_STEP > USB_MAX_CURRENT) {
427 		/* Reached target and voltage is OK - stop */
428 		return;
429 	} else {
430 		bci->usb_cur += USB_CUR_STEP;
431 		schedule_delayed_work(&bci->current_worker, USB_CUR_DELAY);
432 	}
433 	twl4030_charger_update_current(bci);
434 }
435 
436 /*
437  * Enable/Disable USB Charge functionality.
438  */
439 static int twl4030_charger_enable_usb(struct twl4030_bci *bci, bool enable)
440 {
441 	int ret;
442 
443 	if (bci->usb_mode == CHARGE_OFF)
444 		enable = false;
445 	if (enable && !IS_ERR_OR_NULL(bci->transceiver)) {
446 
447 		twl4030_charger_update_current(bci);
448 
449 		/* Need to keep phy powered */
450 		if (!bci->usb_enabled) {
451 			pm_runtime_get_sync(bci->transceiver->dev);
452 			bci->usb_enabled = 1;
453 		}
454 
455 		if (bci->usb_mode == CHARGE_AUTO)
456 			/* forcing the field BCIAUTOUSB (BOOT_BCI[1]) to 1 */
457 			ret = twl4030_clear_set_boot_bci(0, TWL4030_BCIAUTOUSB);
458 
459 		/* forcing USBFASTMCHG(BCIMFSTS4[2]) to 1 */
460 		ret = twl4030_clear_set(TWL_MODULE_MAIN_CHARGE, 0,
461 			TWL4030_USBFASTMCHG, TWL4030_BCIMFSTS4);
462 		if (bci->usb_mode == CHARGE_LINEAR) {
463 			twl4030_clear_set_boot_bci(TWL4030_BCIAUTOAC|TWL4030_CVENAC, 0);
464 			/* Watch dog key: WOVF acknowledge */
465 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x33,
466 					       TWL4030_BCIWDKEY);
467 			/* 0x24 + EKEY6: off mode */
468 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x2a,
469 					       TWL4030_BCIMDKEY);
470 			/* EKEY2: Linear charge: USB path */
471 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x26,
472 					       TWL4030_BCIMDKEY);
473 			/* WDKEY5: stop watchdog count */
474 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xf3,
475 					       TWL4030_BCIWDKEY);
476 			/* enable MFEN3 access */
477 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x9c,
478 					       TWL4030_BCIMFKEY);
479 			 /* ICHGEOCEN - end-of-charge monitor (current < 80mA)
480 			  *                      (charging continues)
481 			  * ICHGLOWEN - current level monitor (charge continues)
482 			  * don't monitor over-current or heat save
483 			  */
484 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xf0,
485 					       TWL4030_BCIMFEN3);
486 		}
487 	} else {
488 		ret = twl4030_clear_set_boot_bci(TWL4030_BCIAUTOUSB, 0);
489 		ret |= twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x2a,
490 					TWL4030_BCIMDKEY);
491 		if (bci->usb_enabled) {
492 			pm_runtime_mark_last_busy(bci->transceiver->dev);
493 			pm_runtime_put_autosuspend(bci->transceiver->dev);
494 			bci->usb_enabled = 0;
495 		}
496 		bci->usb_cur = 0;
497 	}
498 
499 	return ret;
500 }
501 
502 /*
503  * Enable/Disable AC Charge funtionality.
504  */
505 static int twl4030_charger_enable_ac(struct twl4030_bci *bci, bool enable)
506 {
507 	int ret;
508 
509 	if (bci->ac_mode == CHARGE_OFF)
510 		enable = false;
511 
512 	if (enable)
513 		ret = twl4030_clear_set_boot_bci(0, TWL4030_BCIAUTOAC);
514 	else
515 		ret = twl4030_clear_set_boot_bci(TWL4030_BCIAUTOAC, 0);
516 
517 	return ret;
518 }
519 
520 /*
521  * Enable/Disable charging of Backup Battery.
522  */
523 static int twl4030_charger_enable_backup(int uvolt, int uamp)
524 {
525 	int ret;
526 	u8 flags;
527 
528 	if (uvolt < 2500000 ||
529 	    uamp < 25) {
530 		/* disable charging of backup battery */
531 		ret = twl4030_clear_set(TWL_MODULE_PM_RECEIVER,
532 					TWL4030_BBCHEN, 0, TWL4030_BB_CFG);
533 		return ret;
534 	}
535 
536 	flags = TWL4030_BBCHEN;
537 	if (uvolt >= 3200000)
538 		flags |= TWL4030_BBSEL_3V2;
539 	else if (uvolt >= 3100000)
540 		flags |= TWL4030_BBSEL_3V1;
541 	else if (uvolt >= 3000000)
542 		flags |= TWL4030_BBSEL_3V0;
543 	else
544 		flags |= TWL4030_BBSEL_2V5;
545 
546 	if (uamp >= 1000)
547 		flags |= TWL4030_BBISEL_1000uA;
548 	else if (uamp >= 500)
549 		flags |= TWL4030_BBISEL_500uA;
550 	else if (uamp >= 150)
551 		flags |= TWL4030_BBISEL_150uA;
552 	else
553 		flags |= TWL4030_BBISEL_25uA;
554 
555 	ret = twl4030_clear_set(TWL_MODULE_PM_RECEIVER,
556 				TWL4030_BBSEL_MASK | TWL4030_BBISEL_MASK,
557 				flags,
558 				TWL4030_BB_CFG);
559 
560 	return ret;
561 }
562 
563 /*
564  * TWL4030 CHG_PRES (AC charger presence) events
565  */
566 static irqreturn_t twl4030_charger_interrupt(int irq, void *arg)
567 {
568 	struct twl4030_bci *bci = arg;
569 
570 	dev_dbg(bci->dev, "CHG_PRES irq\n");
571 	/* reset current on each 'plug' event */
572 	bci->ac_cur = 500000;
573 	twl4030_charger_update_current(bci);
574 	power_supply_changed(bci->ac);
575 	power_supply_changed(bci->usb);
576 
577 	return IRQ_HANDLED;
578 }
579 
580 /*
581  * TWL4030 BCI monitoring events
582  */
583 static irqreturn_t twl4030_bci_interrupt(int irq, void *arg)
584 {
585 	struct twl4030_bci *bci = arg;
586 	u8 irqs1, irqs2;
587 	int ret;
588 
589 	ret = twl_i2c_read_u8(TWL4030_MODULE_INTERRUPTS, &irqs1,
590 			      TWL4030_INTERRUPTS_BCIISR1A);
591 	if (ret < 0)
592 		return IRQ_HANDLED;
593 
594 	ret = twl_i2c_read_u8(TWL4030_MODULE_INTERRUPTS, &irqs2,
595 			      TWL4030_INTERRUPTS_BCIISR2A);
596 	if (ret < 0)
597 		return IRQ_HANDLED;
598 
599 	dev_dbg(bci->dev, "BCI irq %02x %02x\n", irqs2, irqs1);
600 
601 	if (irqs1 & (TWL4030_ICHGLOW | TWL4030_ICHGEOC)) {
602 		/* charger state change, inform the core */
603 		power_supply_changed(bci->ac);
604 		power_supply_changed(bci->usb);
605 	}
606 	twl4030_charger_update_current(bci);
607 
608 	/* various monitoring events, for now we just log them here */
609 	if (irqs1 & (TWL4030_TBATOR2 | TWL4030_TBATOR1))
610 		dev_warn(bci->dev, "battery temperature out of range\n");
611 
612 	if (irqs1 & TWL4030_BATSTS)
613 		dev_crit(bci->dev, "battery disconnected\n");
614 
615 	if (irqs2 & TWL4030_VBATOV)
616 		dev_crit(bci->dev, "VBAT overvoltage\n");
617 
618 	if (irqs2 & TWL4030_VBUSOV)
619 		dev_crit(bci->dev, "VBUS overvoltage\n");
620 
621 	if (irqs2 & TWL4030_ACCHGOV)
622 		dev_crit(bci->dev, "Ac charger overvoltage\n");
623 
624 	return IRQ_HANDLED;
625 }
626 
627 /*
628  * Provide "max_current" attribute in sysfs.
629  */
630 static ssize_t
631 twl4030_bci_max_current_store(struct device *dev, struct device_attribute *attr,
632 	const char *buf, size_t n)
633 {
634 	struct twl4030_bci *bci = dev_get_drvdata(dev->parent);
635 	int cur = 0;
636 	int status = 0;
637 	status = kstrtoint(buf, 10, &cur);
638 	if (status)
639 		return status;
640 	if (cur < 0)
641 		return -EINVAL;
642 	if (dev == &bci->ac->dev)
643 		bci->ac_cur = cur;
644 	else
645 		bci->usb_cur_target = cur;
646 
647 	twl4030_charger_update_current(bci);
648 	return n;
649 }
650 
651 /*
652  * sysfs max_current show
653  */
654 static ssize_t twl4030_bci_max_current_show(struct device *dev,
655 	struct device_attribute *attr, char *buf)
656 {
657 	int status = 0;
658 	int cur = -1;
659 	u8 bcictl1;
660 	struct twl4030_bci *bci = dev_get_drvdata(dev->parent);
661 
662 	if (dev == &bci->ac->dev) {
663 		if (!bci->ac_is_active)
664 			cur = bci->ac_cur;
665 	} else {
666 		if (bci->ac_is_active)
667 			cur = bci->usb_cur_target;
668 	}
669 	if (cur < 0) {
670 		cur = twl4030bci_read_adc_val(TWL4030_BCIIREF1);
671 		if (cur < 0)
672 			return cur;
673 		status = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1);
674 		if (status < 0)
675 			return status;
676 		cur = regval2ua(cur, bcictl1 & TWL4030_CGAIN);
677 	}
678 	return scnprintf(buf, PAGE_SIZE, "%u\n", cur);
679 }
680 
681 static DEVICE_ATTR(max_current, 0644, twl4030_bci_max_current_show,
682 			twl4030_bci_max_current_store);
683 
684 static void twl4030_bci_usb_work(struct work_struct *data)
685 {
686 	struct twl4030_bci *bci = container_of(data, struct twl4030_bci, work);
687 
688 	switch (bci->event) {
689 	case USB_EVENT_VBUS:
690 	case USB_EVENT_CHARGER:
691 		twl4030_charger_enable_usb(bci, true);
692 		break;
693 	case USB_EVENT_NONE:
694 		twl4030_charger_enable_usb(bci, false);
695 		break;
696 	}
697 }
698 
699 static int twl4030_bci_usb_ncb(struct notifier_block *nb, unsigned long val,
700 			       void *priv)
701 {
702 	struct twl4030_bci *bci = container_of(nb, struct twl4030_bci, usb_nb);
703 
704 	dev_dbg(bci->dev, "OTG notify %lu\n", val);
705 
706 	/* reset current on each 'plug' event */
707 	if (allow_usb)
708 		bci->usb_cur_target = 500000;
709 	else
710 		bci->usb_cur_target = 100000;
711 
712 	bci->event = val;
713 	schedule_work(&bci->work);
714 
715 	return NOTIFY_OK;
716 }
717 
718 /*
719  * sysfs charger enabled store
720  */
721 static ssize_t
722 twl4030_bci_mode_store(struct device *dev, struct device_attribute *attr,
723 			  const char *buf, size_t n)
724 {
725 	struct twl4030_bci *bci = dev_get_drvdata(dev->parent);
726 	int mode;
727 	int status;
728 
729 	if (sysfs_streq(buf, modes[0]))
730 		mode = 0;
731 	else if (sysfs_streq(buf, modes[1]))
732 		mode = 1;
733 	else if (sysfs_streq(buf, modes[2]))
734 		mode = 2;
735 	else
736 		return -EINVAL;
737 	if (dev == &bci->ac->dev) {
738 		if (mode == 2)
739 			return -EINVAL;
740 		twl4030_charger_enable_ac(bci, false);
741 		bci->ac_mode = mode;
742 		status = twl4030_charger_enable_ac(bci, true);
743 	} else {
744 		twl4030_charger_enable_usb(bci, false);
745 		bci->usb_mode = mode;
746 		status = twl4030_charger_enable_usb(bci, true);
747 	}
748 	return (status == 0) ? n : status;
749 }
750 
751 /*
752  * sysfs charger enabled show
753  */
754 static ssize_t
755 twl4030_bci_mode_show(struct device *dev,
756 			     struct device_attribute *attr, char *buf)
757 {
758 	struct twl4030_bci *bci = dev_get_drvdata(dev->parent);
759 	int len = 0;
760 	int i;
761 	int mode = bci->usb_mode;
762 
763 	if (dev == &bci->ac->dev)
764 		mode = bci->ac_mode;
765 
766 	for (i = 0; i < ARRAY_SIZE(modes); i++)
767 		if (mode == i)
768 			len += snprintf(buf+len, PAGE_SIZE-len,
769 					"[%s] ", modes[i]);
770 		else
771 			len += snprintf(buf+len, PAGE_SIZE-len,
772 					"%s ", modes[i]);
773 	buf[len-1] = '\n';
774 	return len;
775 }
776 static DEVICE_ATTR(mode, 0644, twl4030_bci_mode_show,
777 		   twl4030_bci_mode_store);
778 
779 static int twl4030_charger_get_current(void)
780 {
781 	int curr;
782 	int ret;
783 	u8 bcictl1;
784 
785 	curr = twl4030bci_read_adc_val(TWL4030_BCIICHG);
786 	if (curr < 0)
787 		return curr;
788 
789 	ret = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1);
790 	if (ret)
791 		return ret;
792 
793 	return regval2ua(curr, bcictl1 & TWL4030_CGAIN);
794 }
795 
796 /*
797  * Returns the main charge FSM state
798  * Or < 0 on failure.
799  */
800 static int twl4030bci_state(struct twl4030_bci *bci)
801 {
802 	int ret;
803 	u8 state;
804 
805 	ret = twl4030_bci_read(TWL4030_BCIMSTATEC, &state);
806 	if (ret) {
807 		pr_err("twl4030_bci: error reading BCIMSTATEC\n");
808 		return ret;
809 	}
810 
811 	dev_dbg(bci->dev, "state: %02x\n", state);
812 
813 	return state;
814 }
815 
816 static int twl4030_bci_state_to_status(int state)
817 {
818 	state &= TWL4030_MSTATEC_MASK;
819 	if (TWL4030_MSTATEC_QUICK1 <= state && state <= TWL4030_MSTATEC_QUICK7)
820 		return POWER_SUPPLY_STATUS_CHARGING;
821 	else if (TWL4030_MSTATEC_COMPLETE1 <= state &&
822 					state <= TWL4030_MSTATEC_COMPLETE4)
823 		return POWER_SUPPLY_STATUS_FULL;
824 	else
825 		return POWER_SUPPLY_STATUS_NOT_CHARGING;
826 }
827 
828 static int twl4030_bci_get_property(struct power_supply *psy,
829 				    enum power_supply_property psp,
830 				    union power_supply_propval *val)
831 {
832 	struct twl4030_bci *bci = dev_get_drvdata(psy->dev.parent);
833 	int is_charging;
834 	int state;
835 	int ret;
836 
837 	state = twl4030bci_state(bci);
838 	if (state < 0)
839 		return state;
840 
841 	if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
842 		is_charging = state & TWL4030_MSTATEC_USB;
843 	else
844 		is_charging = state & TWL4030_MSTATEC_AC;
845 	if (!is_charging) {
846 		u8 s;
847 		twl4030_bci_read(TWL4030_BCIMDEN, &s);
848 		if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
849 			is_charging = s & 1;
850 		else
851 			is_charging = s & 2;
852 		if (is_charging)
853 			/* A little white lie */
854 			state = TWL4030_MSTATEC_QUICK1;
855 	}
856 
857 	switch (psp) {
858 	case POWER_SUPPLY_PROP_STATUS:
859 		if (is_charging)
860 			val->intval = twl4030_bci_state_to_status(state);
861 		else
862 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
863 		break;
864 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
865 		/* charging must be active for meaningful result */
866 		if (!is_charging)
867 			return -ENODATA;
868 		if (psy->desc->type == POWER_SUPPLY_TYPE_USB) {
869 			ret = twl4030bci_read_adc_val(TWL4030_BCIVBUS);
870 			if (ret < 0)
871 				return ret;
872 			/* BCIVBUS uses ADCIN8, 7/1023 V/step */
873 			val->intval = ret * 6843;
874 		} else {
875 			ret = twl4030bci_read_adc_val(TWL4030_BCIVAC);
876 			if (ret < 0)
877 				return ret;
878 			/* BCIVAC uses ADCIN11, 10/1023 V/step */
879 			val->intval = ret * 9775;
880 		}
881 		break;
882 	case POWER_SUPPLY_PROP_CURRENT_NOW:
883 		if (!is_charging)
884 			return -ENODATA;
885 		/* current measurement is shared between AC and USB */
886 		ret = twl4030_charger_get_current();
887 		if (ret < 0)
888 			return ret;
889 		val->intval = ret;
890 		break;
891 	case POWER_SUPPLY_PROP_ONLINE:
892 		val->intval = is_charging &&
893 			twl4030_bci_state_to_status(state) !=
894 				POWER_SUPPLY_STATUS_NOT_CHARGING;
895 		break;
896 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
897 		val->intval = -1;
898 		if (psy->desc->type != POWER_SUPPLY_TYPE_USB) {
899 			if (!bci->ac_is_active)
900 				val->intval = bci->ac_cur;
901 		} else {
902 			if (bci->ac_is_active)
903 				val->intval = bci->usb_cur_target;
904 		}
905 		if (val->intval < 0) {
906 			u8 bcictl1;
907 
908 			val->intval = twl4030bci_read_adc_val(TWL4030_BCIIREF1);
909 			if (val->intval < 0)
910 				return val->intval;
911 			ret = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1);
912 			if (ret < 0)
913 				return ret;
914 			val->intval = regval2ua(val->intval, bcictl1 &
915 							TWL4030_CGAIN);
916 		}
917 		break;
918 	default:
919 		return -EINVAL;
920 	}
921 
922 	return 0;
923 }
924 
925 static int twl4030_bci_set_property(struct power_supply *psy,
926 				    enum power_supply_property psp,
927 				    const union power_supply_propval *val)
928 {
929 	struct twl4030_bci *bci = dev_get_drvdata(psy->dev.parent);
930 
931 	switch (psp) {
932 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
933 		if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
934 			bci->usb_cur_target = val->intval;
935 		else
936 			bci->ac_cur = val->intval;
937 		twl4030_charger_update_current(bci);
938 		break;
939 	default:
940 		return -EINVAL;
941 	}
942 
943 	return 0;
944 }
945 
946 static int twl4030_bci_property_is_writeable(struct power_supply *psy,
947 				      enum power_supply_property psp)
948 {
949 	switch (psp) {
950 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
951 		return true;
952 	default:
953 		return false;
954 	}
955 }
956 
957 static enum power_supply_property twl4030_charger_props[] = {
958 	POWER_SUPPLY_PROP_STATUS,
959 	POWER_SUPPLY_PROP_ONLINE,
960 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
961 	POWER_SUPPLY_PROP_CURRENT_NOW,
962 	POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
963 };
964 
965 #ifdef CONFIG_OF
966 static const struct twl4030_bci_platform_data *
967 twl4030_bci_parse_dt(struct device *dev)
968 {
969 	struct device_node *np = dev->of_node;
970 	struct twl4030_bci_platform_data *pdata;
971 	u32 num;
972 
973 	if (!np)
974 		return NULL;
975 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
976 	if (!pdata)
977 		return pdata;
978 
979 	if (of_property_read_u32(np, "ti,bb-uvolt", &num) == 0)
980 		pdata->bb_uvolt = num;
981 	if (of_property_read_u32(np, "ti,bb-uamp", &num) == 0)
982 		pdata->bb_uamp = num;
983 	return pdata;
984 }
985 #else
986 static inline const struct twl4030_bci_platform_data *
987 twl4030_bci_parse_dt(struct device *dev)
988 {
989 	return NULL;
990 }
991 #endif
992 
993 static const struct power_supply_desc twl4030_bci_ac_desc = {
994 	.name		= "twl4030_ac",
995 	.type		= POWER_SUPPLY_TYPE_MAINS,
996 	.properties	= twl4030_charger_props,
997 	.num_properties	= ARRAY_SIZE(twl4030_charger_props),
998 	.get_property	= twl4030_bci_get_property,
999 	.set_property	= twl4030_bci_set_property,
1000 	.property_is_writeable	= twl4030_bci_property_is_writeable,
1001 };
1002 
1003 static const struct power_supply_desc twl4030_bci_usb_desc = {
1004 	.name		= "twl4030_usb",
1005 	.type		= POWER_SUPPLY_TYPE_USB,
1006 	.properties	= twl4030_charger_props,
1007 	.num_properties	= ARRAY_SIZE(twl4030_charger_props),
1008 	.get_property	= twl4030_bci_get_property,
1009 	.set_property	= twl4030_bci_set_property,
1010 	.property_is_writeable	= twl4030_bci_property_is_writeable,
1011 };
1012 
1013 static int twl4030_bci_probe(struct platform_device *pdev)
1014 {
1015 	struct twl4030_bci *bci;
1016 	const struct twl4030_bci_platform_data *pdata = pdev->dev.platform_data;
1017 	int ret;
1018 	u32 reg;
1019 
1020 	bci = devm_kzalloc(&pdev->dev, sizeof(*bci), GFP_KERNEL);
1021 	if (bci == NULL)
1022 		return -ENOMEM;
1023 
1024 	if (!pdata)
1025 		pdata = twl4030_bci_parse_dt(&pdev->dev);
1026 
1027 	bci->ichg_eoc = 80100; /* Stop charging when current drops to here */
1028 	bci->ichg_lo = 241000; /* Low threshold */
1029 	bci->ichg_hi = 500000; /* High threshold */
1030 	bci->ac_cur = 500000; /* 500mA */
1031 	if (allow_usb)
1032 		bci->usb_cur_target = 500000;  /* 500mA */
1033 	else
1034 		bci->usb_cur_target = 100000;  /* 100mA */
1035 	bci->usb_mode = CHARGE_AUTO;
1036 	bci->ac_mode = CHARGE_AUTO;
1037 
1038 	bci->dev = &pdev->dev;
1039 	bci->irq_chg = platform_get_irq(pdev, 0);
1040 	bci->irq_bci = platform_get_irq(pdev, 1);
1041 
1042 	platform_set_drvdata(pdev, bci);
1043 
1044 	bci->ac = devm_power_supply_register(&pdev->dev, &twl4030_bci_ac_desc,
1045 					     NULL);
1046 	if (IS_ERR(bci->ac)) {
1047 		ret = PTR_ERR(bci->ac);
1048 		dev_err(&pdev->dev, "failed to register ac: %d\n", ret);
1049 		return ret;
1050 	}
1051 
1052 	bci->usb = devm_power_supply_register(&pdev->dev, &twl4030_bci_usb_desc,
1053 					      NULL);
1054 	if (IS_ERR(bci->usb)) {
1055 		ret = PTR_ERR(bci->usb);
1056 		dev_err(&pdev->dev, "failed to register usb: %d\n", ret);
1057 		return ret;
1058 	}
1059 
1060 	ret = devm_request_threaded_irq(&pdev->dev, bci->irq_chg, NULL,
1061 			twl4030_charger_interrupt, IRQF_ONESHOT, pdev->name,
1062 			bci);
1063 	if (ret < 0) {
1064 		dev_err(&pdev->dev, "could not request irq %d, status %d\n",
1065 			bci->irq_chg, ret);
1066 		return ret;
1067 	}
1068 
1069 	ret = devm_request_threaded_irq(&pdev->dev, bci->irq_bci, NULL,
1070 			twl4030_bci_interrupt, IRQF_ONESHOT, pdev->name, bci);
1071 	if (ret < 0) {
1072 		dev_err(&pdev->dev, "could not request irq %d, status %d\n",
1073 			bci->irq_bci, ret);
1074 		return ret;
1075 	}
1076 
1077 	bci->channel_vac = iio_channel_get(&pdev->dev, "vac");
1078 	if (IS_ERR(bci->channel_vac)) {
1079 		bci->channel_vac = NULL;
1080 		dev_warn(&pdev->dev, "could not request vac iio channel");
1081 	}
1082 
1083 	INIT_WORK(&bci->work, twl4030_bci_usb_work);
1084 	INIT_DELAYED_WORK(&bci->current_worker, twl4030_current_worker);
1085 
1086 	bci->usb_nb.notifier_call = twl4030_bci_usb_ncb;
1087 	if (bci->dev->of_node) {
1088 		struct device_node *phynode;
1089 
1090 		phynode = of_find_compatible_node(bci->dev->of_node->parent,
1091 						  NULL, "ti,twl4030-usb");
1092 		if (phynode)
1093 			bci->transceiver = devm_usb_get_phy_by_node(
1094 				bci->dev, phynode, &bci->usb_nb);
1095 	}
1096 
1097 	/* Enable interrupts now. */
1098 	reg = ~(u32)(TWL4030_ICHGLOW | TWL4030_ICHGEOC | TWL4030_TBATOR2 |
1099 		TWL4030_TBATOR1 | TWL4030_BATSTS);
1100 	ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg,
1101 			       TWL4030_INTERRUPTS_BCIIMR1A);
1102 	if (ret < 0) {
1103 		dev_err(&pdev->dev, "failed to unmask interrupts: %d\n", ret);
1104 		goto fail;
1105 	}
1106 
1107 	reg = ~(u32)(TWL4030_VBATOV | TWL4030_VBUSOV | TWL4030_ACCHGOV);
1108 	ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg,
1109 			       TWL4030_INTERRUPTS_BCIIMR2A);
1110 	if (ret < 0)
1111 		dev_warn(&pdev->dev, "failed to unmask interrupts: %d\n", ret);
1112 
1113 	twl4030_charger_update_current(bci);
1114 	if (device_create_file(&bci->usb->dev, &dev_attr_max_current))
1115 		dev_warn(&pdev->dev, "could not create sysfs file\n");
1116 	if (device_create_file(&bci->usb->dev, &dev_attr_mode))
1117 		dev_warn(&pdev->dev, "could not create sysfs file\n");
1118 	if (device_create_file(&bci->ac->dev, &dev_attr_mode))
1119 		dev_warn(&pdev->dev, "could not create sysfs file\n");
1120 	if (device_create_file(&bci->ac->dev, &dev_attr_max_current))
1121 		dev_warn(&pdev->dev, "could not create sysfs file\n");
1122 
1123 	twl4030_charger_enable_ac(bci, true);
1124 	if (!IS_ERR_OR_NULL(bci->transceiver))
1125 		twl4030_bci_usb_ncb(&bci->usb_nb,
1126 				    bci->transceiver->last_event,
1127 				    NULL);
1128 	else
1129 		twl4030_charger_enable_usb(bci, false);
1130 	if (pdata)
1131 		twl4030_charger_enable_backup(pdata->bb_uvolt,
1132 					      pdata->bb_uamp);
1133 	else
1134 		twl4030_charger_enable_backup(0, 0);
1135 
1136 	return 0;
1137 fail:
1138 	iio_channel_release(bci->channel_vac);
1139 
1140 	return ret;
1141 }
1142 
1143 static int twl4030_bci_remove(struct platform_device *pdev)
1144 {
1145 	struct twl4030_bci *bci = platform_get_drvdata(pdev);
1146 
1147 	twl4030_charger_enable_ac(bci, false);
1148 	twl4030_charger_enable_usb(bci, false);
1149 	twl4030_charger_enable_backup(0, 0);
1150 
1151 	iio_channel_release(bci->channel_vac);
1152 
1153 	device_remove_file(&bci->usb->dev, &dev_attr_max_current);
1154 	device_remove_file(&bci->usb->dev, &dev_attr_mode);
1155 	device_remove_file(&bci->ac->dev, &dev_attr_max_current);
1156 	device_remove_file(&bci->ac->dev, &dev_attr_mode);
1157 	/* mask interrupts */
1158 	twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, 0xff,
1159 			 TWL4030_INTERRUPTS_BCIIMR1A);
1160 	twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, 0xff,
1161 			 TWL4030_INTERRUPTS_BCIIMR2A);
1162 
1163 	return 0;
1164 }
1165 
1166 static const struct of_device_id twl_bci_of_match[] = {
1167 	{.compatible = "ti,twl4030-bci", },
1168 	{ }
1169 };
1170 MODULE_DEVICE_TABLE(of, twl_bci_of_match);
1171 
1172 static struct platform_driver twl4030_bci_driver = {
1173 	.probe = twl4030_bci_probe,
1174 	.remove	= twl4030_bci_remove,
1175 	.driver	= {
1176 		.name	= "twl4030_bci",
1177 		.of_match_table = of_match_ptr(twl_bci_of_match),
1178 	},
1179 };
1180 module_platform_driver(twl4030_bci_driver);
1181 
1182 MODULE_AUTHOR("Gražvydas Ignotas");
1183 MODULE_DESCRIPTION("TWL4030 Battery Charger Interface driver");
1184 MODULE_LICENSE("GPL");
1185 MODULE_ALIAS("platform:twl4030_bci");
1186