xref: /linux/drivers/power/supply/twl4030_charger.c (revision 448ecd5771e255629bef0fb16c9b78c4bbd7bd56)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * TWL4030/TPS65950 BCI (Battery Charger Interface) driver
4  *
5  * Copyright (C) 2010 Gražvydas Ignotas <notasas@gmail.com>
6  *
7  * based on twl4030_bci_battery.c by TI
8  * Copyright (C) 2008 Texas Instruments, Inc.
9  */
10 
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/err.h>
15 #include <linux/of.h>
16 #include <linux/platform_device.h>
17 #include <linux/interrupt.h>
18 #include <linux/mfd/twl.h>
19 #include <linux/power_supply.h>
20 #include <linux/notifier.h>
21 #include <linux/usb/otg.h>
22 #include <linux/iio/consumer.h>
23 
24 #define TWL4030_BCIMDEN		0x00
25 #define TWL4030_BCIMDKEY	0x01
26 #define TWL4030_BCIMSTATEC	0x02
27 #define TWL4030_BCIICHG		0x08
28 #define TWL4030_BCIVAC		0x0a
29 #define TWL4030_BCIVBUS		0x0c
30 #define TWL4030_BCIMFSTS3	0x0F
31 #define TWL4030_BCIMFSTS4	0x10
32 #define TWL4030_BCICTL1		0x23
33 #define TWL4030_BB_CFG		0x12
34 #define TWL4030_BCIIREF1	0x27
35 #define TWL4030_BCIIREF2	0x28
36 #define TWL4030_BCIMFKEY	0x11
37 #define TWL4030_BCIMFEN3	0x14
38 #define TWL4030_BCIMFTH8	0x1d
39 #define TWL4030_BCIMFTH9	0x1e
40 #define TWL4030_BCIWDKEY	0x21
41 
42 #define TWL4030_BCIMFSTS1	0x01
43 
44 #define TWL4030_BCIAUTOWEN	BIT(5)
45 #define TWL4030_CONFIG_DONE	BIT(4)
46 #define TWL4030_CVENAC		BIT(2)
47 #define TWL4030_BCIAUTOUSB	BIT(1)
48 #define TWL4030_BCIAUTOAC	BIT(0)
49 #define TWL4030_CGAIN		BIT(5)
50 #define TWL4030_USBFASTMCHG	BIT(2)
51 #define TWL4030_STS_VBUS	BIT(7)
52 #define TWL4030_STS_USB_ID	BIT(2)
53 #define TWL4030_BBCHEN		BIT(4)
54 #define TWL4030_BBSEL_MASK	0x0c
55 #define TWL4030_BBSEL_2V5	0x00
56 #define TWL4030_BBSEL_3V0	0x04
57 #define TWL4030_BBSEL_3V1	0x08
58 #define TWL4030_BBSEL_3V2	0x0c
59 #define TWL4030_BBISEL_MASK	0x03
60 #define TWL4030_BBISEL_25uA	0x00
61 #define TWL4030_BBISEL_150uA	0x01
62 #define TWL4030_BBISEL_500uA	0x02
63 #define TWL4030_BBISEL_1000uA	0x03
64 
65 #define TWL4030_BATSTSPCHG	BIT(2)
66 #define TWL4030_BATSTSMCHG	BIT(6)
67 
68 /* BCI interrupts */
69 #define TWL4030_WOVF		BIT(0) /* Watchdog overflow */
70 #define TWL4030_TMOVF		BIT(1) /* Timer overflow */
71 #define TWL4030_ICHGHIGH	BIT(2) /* Battery charge current high */
72 #define TWL4030_ICHGLOW		BIT(3) /* Battery cc. low / FSM state change */
73 #define TWL4030_ICHGEOC		BIT(4) /* Battery current end-of-charge */
74 #define TWL4030_TBATOR2		BIT(5) /* Battery temperature out of range 2 */
75 #define TWL4030_TBATOR1		BIT(6) /* Battery temperature out of range 1 */
76 #define TWL4030_BATSTS		BIT(7) /* Battery status */
77 
78 #define TWL4030_VBATLVL		BIT(0) /* VBAT level */
79 #define TWL4030_VBATOV		BIT(1) /* VBAT overvoltage */
80 #define TWL4030_VBUSOV		BIT(2) /* VBUS overvoltage */
81 #define TWL4030_ACCHGOV		BIT(3) /* Ac charger overvoltage */
82 
83 #define TWL4030_MSTATEC_USB		BIT(4)
84 #define TWL4030_MSTATEC_AC		BIT(5)
85 #define TWL4030_MSTATEC_MASK		0x0f
86 #define TWL4030_MSTATEC_QUICK1		0x02
87 #define TWL4030_MSTATEC_QUICK7		0x07
88 #define TWL4030_MSTATEC_COMPLETE1	0x0b
89 #define TWL4030_MSTATEC_COMPLETE4	0x0e
90 
91 /*
92  * If AC (Accessory Charger) voltage exceeds 4.5V (MADC 11)
93  * then AC is available.
94  */
ac_available(struct iio_channel * channel_vac)95 static inline int ac_available(struct iio_channel *channel_vac)
96 {
97 	int val, err;
98 
99 	if (!channel_vac)
100 		return 0;
101 
102 	err = iio_read_channel_processed(channel_vac, &val);
103 	if (err < 0)
104 		return 0;
105 	return val > 4500;
106 }
107 
108 static bool allow_usb;
109 module_param(allow_usb, bool, 0644);
110 MODULE_PARM_DESC(allow_usb, "Allow USB charge drawing default current");
111 
112 struct twl4030_bci {
113 	struct device		*dev;
114 	struct power_supply	*ac;
115 	struct power_supply	*usb;
116 	struct usb_phy		*transceiver;
117 	struct notifier_block	usb_nb;
118 	struct work_struct	work;
119 	int			irq_chg;
120 	int			irq_bci;
121 	int			usb_enabled;
122 
123 	/*
124 	 * ichg_* and *_cur values in uA. If any are 'large', we set
125 	 * CGAIN to '1' which doubles the range for half the
126 	 * precision.
127 	 */
128 	unsigned int		ichg_eoc, ichg_lo, ichg_hi;
129 	unsigned int		usb_cur, ac_cur;
130 	struct iio_channel	*channel_vac;
131 	bool			ac_is_active;
132 	int			usb_mode, ac_mode; /* charging mode requested */
133 #define	CHARGE_OFF	0
134 #define	CHARGE_AUTO	1
135 #define	CHARGE_LINEAR	2
136 
137 	/* When setting the USB current we slowly increase the
138 	 * requested current until target is reached or the voltage
139 	 * drops below 4.75V.  In the latter case we step back one
140 	 * step.
141 	 */
142 	unsigned int		usb_cur_target;
143 	struct delayed_work	current_worker;
144 #define	USB_CUR_STEP	20000	/* 20mA at a time */
145 #define	USB_MIN_VOLT	4750000	/* 4.75V */
146 #define	USB_CUR_DELAY	msecs_to_jiffies(100)
147 #define	USB_MAX_CURRENT	1700000 /* TWL4030 caps at 1.7A */
148 
149 	unsigned long		event;
150 };
151 
152 /* strings for 'usb_mode' values */
153 static const char *modes[] = { "off", "auto", "continuous" };
154 
155 /*
156  * clear and set bits on an given register on a given module
157  */
twl4030_clear_set(u8 mod_no,u8 clear,u8 set,u8 reg)158 static int twl4030_clear_set(u8 mod_no, u8 clear, u8 set, u8 reg)
159 {
160 	u8 val = 0;
161 	int ret;
162 
163 	ret = twl_i2c_read_u8(mod_no, &val, reg);
164 	if (ret)
165 		return ret;
166 
167 	val &= ~clear;
168 	val |= set;
169 
170 	return twl_i2c_write_u8(mod_no, val, reg);
171 }
172 
twl4030_bci_read(u8 reg,u8 * val)173 static int twl4030_bci_read(u8 reg, u8 *val)
174 {
175 	return twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, val, reg);
176 }
177 
twl4030_clear_set_boot_bci(u8 clear,u8 set)178 static int twl4030_clear_set_boot_bci(u8 clear, u8 set)
179 {
180 	return twl4030_clear_set(TWL_MODULE_PM_MASTER, clear,
181 			TWL4030_CONFIG_DONE | TWL4030_BCIAUTOWEN | set,
182 			TWL4030_PM_MASTER_BOOT_BCI);
183 }
184 
twl4030bci_read_adc_val(u8 reg)185 static int twl4030bci_read_adc_val(u8 reg)
186 {
187 	int ret, temp;
188 	u8 val;
189 
190 	/* read MSB */
191 	ret = twl4030_bci_read(reg + 1, &val);
192 	if (ret)
193 		return ret;
194 
195 	temp = (int)(val & 0x03) << 8;
196 
197 	/* read LSB */
198 	ret = twl4030_bci_read(reg, &val);
199 	if (ret)
200 		return ret;
201 
202 	return temp | val;
203 }
204 
205 /*
206  * TI provided formulas:
207  * CGAIN == 0: ICHG = (BCIICHG * 1.7) / (2^10 - 1) - 0.85
208  * CGAIN == 1: ICHG = (BCIICHG * 3.4) / (2^10 - 1) - 1.7
209  * Here we use integer approximation of:
210  * CGAIN == 0: val * 1.6618 - 0.85 * 1000
211  * CGAIN == 1: (val * 1.6618 - 0.85 * 1000) * 2
212  */
213 /*
214  * convert twl register value for currents into uA
215  */
regval2ua(int regval,bool cgain)216 static int regval2ua(int regval, bool cgain)
217 {
218 	if (cgain)
219 		return (regval * 16618 - 8500 * 1000) / 5;
220 	else
221 		return (regval * 16618 - 8500 * 1000) / 10;
222 }
223 
224 /*
225  * convert uA currents into twl register value
226  */
ua2regval(int ua,bool cgain)227 static int ua2regval(int ua, bool cgain)
228 {
229 	int ret;
230 	if (cgain)
231 		ua /= 2;
232 	ret = (ua * 10 + 8500 * 1000) / 16618;
233 	/* rounding problems */
234 	if (ret < 512)
235 		ret = 512;
236 	return ret;
237 }
238 
twl4030_charger_update_current(struct twl4030_bci * bci)239 static int twl4030_charger_update_current(struct twl4030_bci *bci)
240 {
241 	int status;
242 	int cur;
243 	unsigned reg, cur_reg;
244 	u8 bcictl1, oldreg, fullreg;
245 	bool cgain = false;
246 	u8 boot_bci;
247 
248 	/*
249 	 * If AC (Accessory Charger) voltage exceeds 4.5V (MADC 11)
250 	 * and AC is enabled, set current for 'ac'
251 	 */
252 	if (ac_available(bci->channel_vac)) {
253 		cur = bci->ac_cur;
254 		bci->ac_is_active = true;
255 	} else {
256 		cur = bci->usb_cur;
257 		bci->ac_is_active = false;
258 		if (cur > bci->usb_cur_target) {
259 			cur = bci->usb_cur_target;
260 			bci->usb_cur = cur;
261 		}
262 		if (cur < bci->usb_cur_target)
263 			schedule_delayed_work(&bci->current_worker, USB_CUR_DELAY);
264 	}
265 
266 	/* First, check thresholds and see if cgain is needed */
267 	if (bci->ichg_eoc >= 200000)
268 		cgain = true;
269 	if (bci->ichg_lo >= 400000)
270 		cgain = true;
271 	if (bci->ichg_hi >= 820000)
272 		cgain = true;
273 	if (cur > 852000)
274 		cgain = true;
275 
276 	status = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1);
277 	if (status < 0)
278 		return status;
279 	if (twl_i2c_read_u8(TWL_MODULE_PM_MASTER, &boot_bci,
280 			    TWL4030_PM_MASTER_BOOT_BCI) < 0)
281 		boot_bci = 0;
282 	boot_bci &= 7;
283 
284 	if ((!!cgain) != !!(bcictl1 & TWL4030_CGAIN))
285 		/* Need to turn for charging while we change the
286 		 * CGAIN bit.  Leave it off while everything is
287 		 * updated.
288 		 */
289 		twl4030_clear_set_boot_bci(boot_bci, 0);
290 
291 	/*
292 	 * For ichg_eoc, the hardware only supports reg values matching
293 	 * 100XXXX000, and requires the XXXX be stored in the high nibble
294 	 * of TWL4030_BCIMFTH8.
295 	 */
296 	reg = ua2regval(bci->ichg_eoc, cgain);
297 	if (reg > 0x278)
298 		reg = 0x278;
299 	if (reg < 0x200)
300 		reg = 0x200;
301 	reg = (reg >> 3) & 0xf;
302 	fullreg = reg << 4;
303 
304 	/*
305 	 * For ichg_lo, reg value must match 10XXXX0000.
306 	 * XXXX is stored in low nibble of TWL4030_BCIMFTH8.
307 	 */
308 	reg = ua2regval(bci->ichg_lo, cgain);
309 	if (reg > 0x2F0)
310 		reg = 0x2F0;
311 	if (reg < 0x200)
312 		reg = 0x200;
313 	reg = (reg >> 4) & 0xf;
314 	fullreg |= reg;
315 
316 	/* ichg_eoc and ichg_lo live in same register */
317 	status = twl4030_bci_read(TWL4030_BCIMFTH8, &oldreg);
318 	if (status < 0)
319 		return status;
320 	if (oldreg != fullreg) {
321 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xF4,
322 					  TWL4030_BCIMFKEY);
323 		if (status < 0)
324 			return status;
325 		twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
326 				 fullreg, TWL4030_BCIMFTH8);
327 	}
328 
329 	/* ichg_hi threshold must be 1XXXX01100 (I think) */
330 	reg = ua2regval(bci->ichg_hi, cgain);
331 	if (reg > 0x3E0)
332 		reg = 0x3E0;
333 	if (reg < 0x200)
334 		reg = 0x200;
335 	fullreg = (reg >> 5) & 0xF;
336 	fullreg <<= 4;
337 	status = twl4030_bci_read(TWL4030_BCIMFTH9, &oldreg);
338 	if (status < 0)
339 		return status;
340 	if ((oldreg & 0xF0) != fullreg) {
341 		fullreg |= (oldreg & 0x0F);
342 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xE7,
343 					  TWL4030_BCIMFKEY);
344 		if (status < 0)
345 			return status;
346 		twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
347 				 fullreg, TWL4030_BCIMFTH9);
348 	}
349 
350 	/*
351 	 * And finally, set the current.  This is stored in
352 	 * two registers.
353 	 */
354 	reg = ua2regval(cur, cgain);
355 	/* we have only 10 bits */
356 	if (reg > 0x3ff)
357 		reg = 0x3ff;
358 	status = twl4030_bci_read(TWL4030_BCIIREF1, &oldreg);
359 	if (status < 0)
360 		return status;
361 	cur_reg = oldreg;
362 	status = twl4030_bci_read(TWL4030_BCIIREF2, &oldreg);
363 	if (status < 0)
364 		return status;
365 	cur_reg |= oldreg << 8;
366 	if (reg != cur_reg) {
367 		/* disable write protection for one write access for
368 		 * BCIIREF */
369 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xE7,
370 					  TWL4030_BCIMFKEY);
371 		if (status < 0)
372 			return status;
373 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
374 					  (reg & 0x100) ? 3 : 2,
375 					  TWL4030_BCIIREF2);
376 		if (status < 0)
377 			return status;
378 		/* disable write protection for one write access for
379 		 * BCIIREF */
380 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xE7,
381 					  TWL4030_BCIMFKEY);
382 		if (status < 0)
383 			return status;
384 		status = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
385 					  reg & 0xff,
386 					  TWL4030_BCIIREF1);
387 	}
388 	if ((!!cgain) != !!(bcictl1 & TWL4030_CGAIN)) {
389 		/* Flip CGAIN and re-enable charging */
390 		bcictl1 ^= TWL4030_CGAIN;
391 		twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
392 				 bcictl1, TWL4030_BCICTL1);
393 		twl4030_clear_set_boot_bci(0, boot_bci);
394 	}
395 	return 0;
396 }
397 
398 static int twl4030_charger_get_current(void);
399 
twl4030_current_worker(struct work_struct * data)400 static void twl4030_current_worker(struct work_struct *data)
401 {
402 	int v, curr;
403 	int res;
404 	struct twl4030_bci *bci = container_of(data, struct twl4030_bci,
405 					       current_worker.work);
406 
407 	res = twl4030bci_read_adc_val(TWL4030_BCIVBUS);
408 	if (res < 0)
409 		v = 0;
410 	else
411 		/* BCIVBUS uses ADCIN8, 7/1023 V/step */
412 		v = res * 6843;
413 	curr = twl4030_charger_get_current();
414 
415 	dev_dbg(bci->dev, "v=%d cur=%d limit=%d target=%d\n", v, curr,
416 		bci->usb_cur, bci->usb_cur_target);
417 
418 	if (v < USB_MIN_VOLT) {
419 		/* Back up and stop adjusting. */
420 		if (bci->usb_cur >= USB_CUR_STEP)
421 			bci->usb_cur -= USB_CUR_STEP;
422 		bci->usb_cur_target = bci->usb_cur;
423 	} else if (bci->usb_cur >= bci->usb_cur_target ||
424 		   bci->usb_cur + USB_CUR_STEP > USB_MAX_CURRENT) {
425 		/* Reached target and voltage is OK - stop */
426 		return;
427 	} else {
428 		bci->usb_cur += USB_CUR_STEP;
429 		schedule_delayed_work(&bci->current_worker, USB_CUR_DELAY);
430 	}
431 	twl4030_charger_update_current(bci);
432 }
433 
434 /*
435  * Enable/Disable USB Charge functionality.
436  */
twl4030_charger_enable_usb(struct twl4030_bci * bci,bool enable)437 static int twl4030_charger_enable_usb(struct twl4030_bci *bci, bool enable)
438 {
439 	int ret;
440 	u32 reg;
441 
442 	if (bci->usb_mode == CHARGE_OFF)
443 		enable = false;
444 	if (enable && !IS_ERR_OR_NULL(bci->transceiver)) {
445 
446 		twl4030_charger_update_current(bci);
447 
448 		/* Need to keep phy powered */
449 		if (!bci->usb_enabled) {
450 			pm_runtime_get_sync(bci->transceiver->dev);
451 			bci->usb_enabled = 1;
452 		}
453 
454 		if (bci->usb_mode == CHARGE_AUTO) {
455 			/* Enable interrupts now. */
456 			reg = ~(u32)(TWL4030_ICHGLOW | TWL4030_ICHGEOC |
457 					TWL4030_TBATOR2 | TWL4030_TBATOR1 |
458 					TWL4030_BATSTS);
459 			ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg,
460 				       TWL4030_INTERRUPTS_BCIIMR1A);
461 			if (ret < 0) {
462 				dev_err(bci->dev,
463 					"failed to unmask interrupts: %d\n",
464 					ret);
465 				return ret;
466 			}
467 			/* forcing the field BCIAUTOUSB (BOOT_BCI[1]) to 1 */
468 			ret = twl4030_clear_set_boot_bci(0, TWL4030_BCIAUTOUSB);
469 		}
470 
471 		/* forcing USBFASTMCHG(BCIMFSTS4[2]) to 1 */
472 		ret = twl4030_clear_set(TWL_MODULE_MAIN_CHARGE, 0,
473 			TWL4030_USBFASTMCHG, TWL4030_BCIMFSTS4);
474 		if (bci->usb_mode == CHARGE_LINEAR) {
475 			/* Enable interrupts now. */
476 			reg = ~(u32)(TWL4030_ICHGLOW | TWL4030_TBATOR2 |
477 					TWL4030_TBATOR1 | TWL4030_BATSTS);
478 			ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg,
479 				       TWL4030_INTERRUPTS_BCIIMR1A);
480 			if (ret < 0) {
481 				dev_err(bci->dev,
482 					"failed to unmask interrupts: %d\n",
483 					ret);
484 				return ret;
485 			}
486 			twl4030_clear_set_boot_bci(TWL4030_BCIAUTOAC|TWL4030_CVENAC, 0);
487 			/* Watch dog key: WOVF acknowledge */
488 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x33,
489 					       TWL4030_BCIWDKEY);
490 			/* 0x24 + EKEY6: off mode */
491 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x2a,
492 					       TWL4030_BCIMDKEY);
493 			/* EKEY2: Linear charge: USB path */
494 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x26,
495 					       TWL4030_BCIMDKEY);
496 			/* WDKEY5: stop watchdog count */
497 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xf3,
498 					       TWL4030_BCIWDKEY);
499 			/* enable MFEN3 access */
500 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x9c,
501 					       TWL4030_BCIMFKEY);
502 			 /* ICHGEOCEN - end-of-charge monitor (current < 80mA)
503 			  *                      (charging continues)
504 			  * ICHGLOWEN - current level monitor (charge continues)
505 			  * don't monitor over-current or heat save
506 			  */
507 			ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0xf0,
508 					       TWL4030_BCIMFEN3);
509 		}
510 	} else {
511 		ret = twl4030_clear_set_boot_bci(TWL4030_BCIAUTOUSB, 0);
512 		ret |= twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 0x2a,
513 					TWL4030_BCIMDKEY);
514 		if (bci->usb_enabled) {
515 			pm_runtime_mark_last_busy(bci->transceiver->dev);
516 			pm_runtime_put_autosuspend(bci->transceiver->dev);
517 			bci->usb_enabled = 0;
518 		}
519 		bci->usb_cur = 0;
520 	}
521 
522 	return ret;
523 }
524 
525 /*
526  * Enable/Disable AC Charge funtionality.
527  */
twl4030_charger_enable_ac(struct twl4030_bci * bci,bool enable)528 static int twl4030_charger_enable_ac(struct twl4030_bci *bci, bool enable)
529 {
530 	int ret;
531 
532 	if (bci->ac_mode == CHARGE_OFF)
533 		enable = false;
534 
535 	if (enable)
536 		ret = twl4030_clear_set_boot_bci(0, TWL4030_BCIAUTOAC);
537 	else
538 		ret = twl4030_clear_set_boot_bci(TWL4030_BCIAUTOAC, 0);
539 
540 	return ret;
541 }
542 
543 /*
544  * Enable/Disable charging of Backup Battery.
545  */
twl4030_charger_enable_backup(int uvolt,int uamp)546 static int twl4030_charger_enable_backup(int uvolt, int uamp)
547 {
548 	int ret;
549 	u8 flags;
550 
551 	if (uvolt < 2500000 ||
552 	    uamp < 25) {
553 		/* disable charging of backup battery */
554 		ret = twl4030_clear_set(TWL_MODULE_PM_RECEIVER,
555 					TWL4030_BBCHEN, 0, TWL4030_BB_CFG);
556 		return ret;
557 	}
558 
559 	flags = TWL4030_BBCHEN;
560 	if (uvolt >= 3200000)
561 		flags |= TWL4030_BBSEL_3V2;
562 	else if (uvolt >= 3100000)
563 		flags |= TWL4030_BBSEL_3V1;
564 	else if (uvolt >= 3000000)
565 		flags |= TWL4030_BBSEL_3V0;
566 	else
567 		flags |= TWL4030_BBSEL_2V5;
568 
569 	if (uamp >= 1000)
570 		flags |= TWL4030_BBISEL_1000uA;
571 	else if (uamp >= 500)
572 		flags |= TWL4030_BBISEL_500uA;
573 	else if (uamp >= 150)
574 		flags |= TWL4030_BBISEL_150uA;
575 	else
576 		flags |= TWL4030_BBISEL_25uA;
577 
578 	ret = twl4030_clear_set(TWL_MODULE_PM_RECEIVER,
579 				TWL4030_BBSEL_MASK | TWL4030_BBISEL_MASK,
580 				flags,
581 				TWL4030_BB_CFG);
582 
583 	return ret;
584 }
585 
586 /*
587  * TWL4030 CHG_PRES (AC charger presence) events
588  */
twl4030_charger_interrupt(int irq,void * arg)589 static irqreturn_t twl4030_charger_interrupt(int irq, void *arg)
590 {
591 	struct twl4030_bci *bci = arg;
592 
593 	dev_dbg(bci->dev, "CHG_PRES irq\n");
594 	/* reset current on each 'plug' event */
595 	bci->ac_cur = 500000;
596 	twl4030_charger_update_current(bci);
597 	power_supply_changed(bci->ac);
598 	power_supply_changed(bci->usb);
599 
600 	return IRQ_HANDLED;
601 }
602 
603 /*
604  * TWL4030 BCI monitoring events
605  */
twl4030_bci_interrupt(int irq,void * arg)606 static irqreturn_t twl4030_bci_interrupt(int irq, void *arg)
607 {
608 	struct twl4030_bci *bci = arg;
609 	u8 irqs1, irqs2;
610 	int ret;
611 
612 	ret = twl_i2c_read_u8(TWL4030_MODULE_INTERRUPTS, &irqs1,
613 			      TWL4030_INTERRUPTS_BCIISR1A);
614 	if (ret < 0)
615 		return IRQ_HANDLED;
616 
617 	ret = twl_i2c_read_u8(TWL4030_MODULE_INTERRUPTS, &irqs2,
618 			      TWL4030_INTERRUPTS_BCIISR2A);
619 	if (ret < 0)
620 		return IRQ_HANDLED;
621 
622 	dev_dbg(bci->dev, "BCI irq %02x %02x\n", irqs2, irqs1);
623 
624 	if (irqs1 & (TWL4030_ICHGLOW | TWL4030_ICHGEOC)) {
625 		/* charger state change, inform the core */
626 		power_supply_changed(bci->ac);
627 		power_supply_changed(bci->usb);
628 	}
629 	twl4030_charger_update_current(bci);
630 
631 	/* various monitoring events, for now we just log them here */
632 	if (irqs1 & (TWL4030_TBATOR2 | TWL4030_TBATOR1))
633 		dev_warn(bci->dev, "battery temperature out of range\n");
634 
635 	if (irqs1 & TWL4030_BATSTS)
636 		dev_crit(bci->dev, "battery disconnected\n");
637 
638 	if (irqs2 & TWL4030_VBATOV)
639 		dev_crit(bci->dev, "VBAT overvoltage\n");
640 
641 	if (irqs2 & TWL4030_VBUSOV)
642 		dev_crit(bci->dev, "VBUS overvoltage\n");
643 
644 	if (irqs2 & TWL4030_ACCHGOV)
645 		dev_crit(bci->dev, "Ac charger overvoltage\n");
646 
647 	return IRQ_HANDLED;
648 }
649 
twl4030_bci_usb_work(struct work_struct * data)650 static void twl4030_bci_usb_work(struct work_struct *data)
651 {
652 	struct twl4030_bci *bci = container_of(data, struct twl4030_bci, work);
653 
654 	switch (bci->event) {
655 	case USB_EVENT_VBUS:
656 	case USB_EVENT_CHARGER:
657 		twl4030_charger_enable_usb(bci, true);
658 		break;
659 	case USB_EVENT_NONE:
660 		twl4030_charger_enable_usb(bci, false);
661 		break;
662 	}
663 }
664 
twl4030_bci_usb_ncb(struct notifier_block * nb,unsigned long val,void * priv)665 static int twl4030_bci_usb_ncb(struct notifier_block *nb, unsigned long val,
666 			       void *priv)
667 {
668 	struct twl4030_bci *bci = container_of(nb, struct twl4030_bci, usb_nb);
669 
670 	dev_dbg(bci->dev, "OTG notify %lu\n", val);
671 
672 	/* reset current on each 'plug' event */
673 	if (allow_usb)
674 		bci->usb_cur_target = 500000;
675 	else
676 		bci->usb_cur_target = 100000;
677 
678 	bci->event = val;
679 	schedule_work(&bci->work);
680 
681 	return NOTIFY_OK;
682 }
683 
684 /*
685  * sysfs charger enabled store
686  */
687 static ssize_t
twl4030_bci_mode_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t n)688 twl4030_bci_mode_store(struct device *dev, struct device_attribute *attr,
689 			  const char *buf, size_t n)
690 {
691 	struct twl4030_bci *bci = dev_get_drvdata(dev->parent);
692 	int mode;
693 	int status;
694 
695 	mode = sysfs_match_string(modes, buf);
696 	if (mode < 0)
697 		return mode;
698 
699 	if (dev == &bci->ac->dev) {
700 		if (mode == 2)
701 			return -EINVAL;
702 		twl4030_charger_enable_ac(bci, false);
703 		bci->ac_mode = mode;
704 		status = twl4030_charger_enable_ac(bci, true);
705 	} else {
706 		twl4030_charger_enable_usb(bci, false);
707 		bci->usb_mode = mode;
708 		status = twl4030_charger_enable_usb(bci, true);
709 	}
710 	return (status == 0) ? n : status;
711 }
712 
713 /*
714  * sysfs charger enabled show
715  */
716 static ssize_t
twl4030_bci_mode_show(struct device * dev,struct device_attribute * attr,char * buf)717 twl4030_bci_mode_show(struct device *dev,
718 			     struct device_attribute *attr, char *buf)
719 {
720 	struct twl4030_bci *bci = dev_get_drvdata(dev->parent);
721 	int len = 0;
722 	int i;
723 	int mode = bci->usb_mode;
724 
725 	if (dev == &bci->ac->dev)
726 		mode = bci->ac_mode;
727 
728 	for (i = 0; i < ARRAY_SIZE(modes); i++)
729 		if (mode == i)
730 			len += sysfs_emit_at(buf, len, "[%s] ", modes[i]);
731 		else
732 			len += sysfs_emit_at(buf, len, "%s ", modes[i]);
733 	buf[len-1] = '\n';
734 	return len;
735 }
736 static DEVICE_ATTR(mode, 0644, twl4030_bci_mode_show,
737 		   twl4030_bci_mode_store);
738 
twl4030_charger_get_current(void)739 static int twl4030_charger_get_current(void)
740 {
741 	int curr;
742 	int ret;
743 	u8 bcictl1;
744 
745 	curr = twl4030bci_read_adc_val(TWL4030_BCIICHG);
746 	if (curr < 0)
747 		return curr;
748 
749 	ret = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1);
750 	if (ret)
751 		return ret;
752 
753 	return regval2ua(curr, bcictl1 & TWL4030_CGAIN);
754 }
755 
756 /*
757  * Returns the main charge FSM state
758  * Or < 0 on failure.
759  */
twl4030bci_state(struct twl4030_bci * bci)760 static int twl4030bci_state(struct twl4030_bci *bci)
761 {
762 	int ret;
763 	u8 state;
764 
765 	ret = twl4030_bci_read(TWL4030_BCIMSTATEC, &state);
766 	if (ret) {
767 		dev_err(bci->dev, "error reading BCIMSTATEC\n");
768 		return ret;
769 	}
770 
771 	dev_dbg(bci->dev, "state: %02x\n", state);
772 
773 	return state;
774 }
775 
twl4030_bci_state_to_status(int state)776 static int twl4030_bci_state_to_status(int state)
777 {
778 	state &= TWL4030_MSTATEC_MASK;
779 	if (TWL4030_MSTATEC_QUICK1 <= state && state <= TWL4030_MSTATEC_QUICK7)
780 		return POWER_SUPPLY_STATUS_CHARGING;
781 	else if (TWL4030_MSTATEC_COMPLETE1 <= state &&
782 					state <= TWL4030_MSTATEC_COMPLETE4)
783 		return POWER_SUPPLY_STATUS_FULL;
784 	else
785 		return POWER_SUPPLY_STATUS_NOT_CHARGING;
786 }
787 
twl4030_bci_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)788 static int twl4030_bci_get_property(struct power_supply *psy,
789 				    enum power_supply_property psp,
790 				    union power_supply_propval *val)
791 {
792 	struct twl4030_bci *bci = dev_get_drvdata(psy->dev.parent);
793 	int is_charging;
794 	int state;
795 	int ret;
796 
797 	state = twl4030bci_state(bci);
798 	if (state < 0)
799 		return state;
800 
801 	if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
802 		is_charging = state & TWL4030_MSTATEC_USB;
803 	else
804 		is_charging = state & TWL4030_MSTATEC_AC;
805 	if (!is_charging) {
806 		u8 s;
807 		ret = twl4030_bci_read(TWL4030_BCIMDEN, &s);
808 		if (ret < 0)
809 			return ret;
810 		if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
811 			is_charging = s & 1;
812 		else
813 			is_charging = s & 2;
814 		if (is_charging)
815 			/* A little white lie */
816 			state = TWL4030_MSTATEC_QUICK1;
817 	}
818 
819 	switch (psp) {
820 	case POWER_SUPPLY_PROP_STATUS:
821 		if (is_charging)
822 			val->intval = twl4030_bci_state_to_status(state);
823 		else
824 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
825 		break;
826 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
827 		/* charging must be active for meaningful result */
828 		if (!is_charging)
829 			return -ENODATA;
830 		if (psy->desc->type == POWER_SUPPLY_TYPE_USB) {
831 			ret = twl4030bci_read_adc_val(TWL4030_BCIVBUS);
832 			if (ret < 0)
833 				return ret;
834 			/* BCIVBUS uses ADCIN8, 7/1023 V/step */
835 			val->intval = ret * 6843;
836 		} else {
837 			ret = twl4030bci_read_adc_val(TWL4030_BCIVAC);
838 			if (ret < 0)
839 				return ret;
840 			/* BCIVAC uses ADCIN11, 10/1023 V/step */
841 			val->intval = ret * 9775;
842 		}
843 		break;
844 	case POWER_SUPPLY_PROP_CURRENT_NOW:
845 		if (!is_charging)
846 			return -ENODATA;
847 		/* current measurement is shared between AC and USB */
848 		ret = twl4030_charger_get_current();
849 		if (ret < 0)
850 			return ret;
851 		val->intval = ret;
852 		break;
853 	case POWER_SUPPLY_PROP_ONLINE:
854 		val->intval = is_charging &&
855 			twl4030_bci_state_to_status(state) !=
856 				POWER_SUPPLY_STATUS_NOT_CHARGING;
857 		break;
858 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
859 		val->intval = -1;
860 		if (psy->desc->type != POWER_SUPPLY_TYPE_USB) {
861 			if (!bci->ac_is_active)
862 				val->intval = bci->ac_cur;
863 		} else {
864 			if (bci->ac_is_active)
865 				val->intval = bci->usb_cur_target;
866 		}
867 		if (val->intval < 0) {
868 			u8 bcictl1;
869 
870 			val->intval = twl4030bci_read_adc_val(TWL4030_BCIIREF1);
871 			if (val->intval < 0)
872 				return val->intval;
873 			ret = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1);
874 			if (ret < 0)
875 				return ret;
876 			val->intval = regval2ua(val->intval, bcictl1 &
877 							TWL4030_CGAIN);
878 		}
879 		break;
880 	default:
881 		return -EINVAL;
882 	}
883 
884 	return 0;
885 }
886 
twl4030_bci_set_property(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val)887 static int twl4030_bci_set_property(struct power_supply *psy,
888 				    enum power_supply_property psp,
889 				    const union power_supply_propval *val)
890 {
891 	struct twl4030_bci *bci = dev_get_drvdata(psy->dev.parent);
892 
893 	switch (psp) {
894 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
895 		if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
896 			bci->usb_cur_target = val->intval;
897 		else
898 			bci->ac_cur = val->intval;
899 		twl4030_charger_update_current(bci);
900 		break;
901 	default:
902 		return -EINVAL;
903 	}
904 
905 	return 0;
906 }
907 
twl4030_bci_property_is_writeable(struct power_supply * psy,enum power_supply_property psp)908 static int twl4030_bci_property_is_writeable(struct power_supply *psy,
909 				      enum power_supply_property psp)
910 {
911 	switch (psp) {
912 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
913 		return true;
914 	default:
915 		return false;
916 	}
917 }
918 
919 static enum power_supply_property twl4030_charger_props[] = {
920 	POWER_SUPPLY_PROP_STATUS,
921 	POWER_SUPPLY_PROP_ONLINE,
922 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
923 	POWER_SUPPLY_PROP_CURRENT_NOW,
924 	POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
925 };
926 
927 #ifdef CONFIG_OF
928 static const struct twl4030_bci_platform_data *
twl4030_bci_parse_dt(struct device * dev)929 twl4030_bci_parse_dt(struct device *dev)
930 {
931 	struct device_node *np = dev->of_node;
932 	struct twl4030_bci_platform_data *pdata;
933 	u32 num;
934 
935 	if (!np)
936 		return NULL;
937 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
938 	if (!pdata)
939 		return pdata;
940 
941 	if (of_property_read_u32(np, "ti,bb-uvolt", &num) == 0)
942 		pdata->bb_uvolt = num;
943 	if (of_property_read_u32(np, "ti,bb-uamp", &num) == 0)
944 		pdata->bb_uamp = num;
945 	return pdata;
946 }
947 #else
948 static inline const struct twl4030_bci_platform_data *
twl4030_bci_parse_dt(struct device * dev)949 twl4030_bci_parse_dt(struct device *dev)
950 {
951 	return NULL;
952 }
953 #endif
954 
955 static const struct power_supply_desc twl4030_bci_ac_desc = {
956 	.name		= "twl4030_ac",
957 	.type		= POWER_SUPPLY_TYPE_MAINS,
958 	.properties	= twl4030_charger_props,
959 	.num_properties	= ARRAY_SIZE(twl4030_charger_props),
960 	.get_property	= twl4030_bci_get_property,
961 	.set_property	= twl4030_bci_set_property,
962 	.property_is_writeable	= twl4030_bci_property_is_writeable,
963 };
964 
965 static const struct power_supply_desc twl4030_bci_usb_desc = {
966 	.name		= "twl4030_usb",
967 	.type		= POWER_SUPPLY_TYPE_USB,
968 	.properties	= twl4030_charger_props,
969 	.num_properties	= ARRAY_SIZE(twl4030_charger_props),
970 	.get_property	= twl4030_bci_get_property,
971 	.set_property	= twl4030_bci_set_property,
972 	.property_is_writeable	= twl4030_bci_property_is_writeable,
973 };
974 
twl4030_bci_probe(struct platform_device * pdev)975 static int twl4030_bci_probe(struct platform_device *pdev)
976 {
977 	struct twl4030_bci *bci;
978 	const struct twl4030_bci_platform_data *pdata = pdev->dev.platform_data;
979 	int ret;
980 	u32 reg;
981 
982 	bci = devm_kzalloc(&pdev->dev, sizeof(*bci), GFP_KERNEL);
983 	if (bci == NULL)
984 		return -ENOMEM;
985 
986 	if (!pdata)
987 		pdata = twl4030_bci_parse_dt(&pdev->dev);
988 
989 	bci->ichg_eoc = 80100; /* Stop charging when current drops to here */
990 	bci->ichg_lo = 241000; /* Low threshold */
991 	bci->ichg_hi = 500000; /* High threshold */
992 	bci->ac_cur = 500000; /* 500mA */
993 	if (allow_usb)
994 		bci->usb_cur_target = 500000;  /* 500mA */
995 	else
996 		bci->usb_cur_target = 100000;  /* 100mA */
997 	bci->usb_mode = CHARGE_AUTO;
998 	bci->ac_mode = CHARGE_AUTO;
999 
1000 	bci->dev = &pdev->dev;
1001 	bci->irq_chg = platform_get_irq(pdev, 0);
1002 	bci->irq_bci = platform_get_irq(pdev, 1);
1003 
1004 	platform_set_drvdata(pdev, bci);
1005 
1006 	INIT_WORK(&bci->work, twl4030_bci_usb_work);
1007 	INIT_DELAYED_WORK(&bci->current_worker, twl4030_current_worker);
1008 
1009 	bci->channel_vac = devm_iio_channel_get(&pdev->dev, "vac");
1010 	if (IS_ERR(bci->channel_vac)) {
1011 		ret = PTR_ERR(bci->channel_vac);
1012 		if (ret == -EPROBE_DEFER)
1013 			return ret;	/* iio not ready */
1014 		dev_warn(&pdev->dev, "could not request vac iio channel (%d)",
1015 			ret);
1016 		bci->channel_vac = NULL;
1017 	}
1018 
1019 	if (bci->dev->of_node) {
1020 		struct device_node *phynode;
1021 
1022 		phynode = of_get_compatible_child(bci->dev->of_node->parent,
1023 						  "ti,twl4030-usb");
1024 		if (phynode) {
1025 			bci->usb_nb.notifier_call = twl4030_bci_usb_ncb;
1026 			bci->transceiver = devm_usb_get_phy_by_node(
1027 				bci->dev, phynode, &bci->usb_nb);
1028 			of_node_put(phynode);
1029 			if (IS_ERR(bci->transceiver)) {
1030 				ret = PTR_ERR(bci->transceiver);
1031 				if (ret == -EPROBE_DEFER)
1032 					return ret;	/* phy not ready */
1033 				dev_warn(&pdev->dev, "could not request transceiver (%d)",
1034 					ret);
1035 				bci->transceiver = NULL;
1036 			}
1037 		}
1038 	}
1039 
1040 	bci->ac = devm_power_supply_register(&pdev->dev, &twl4030_bci_ac_desc,
1041 					     NULL);
1042 	if (IS_ERR(bci->ac)) {
1043 		ret = PTR_ERR(bci->ac);
1044 		dev_err(&pdev->dev, "failed to register ac: %d\n", ret);
1045 		return ret;
1046 	}
1047 
1048 	bci->usb = devm_power_supply_register(&pdev->dev, &twl4030_bci_usb_desc,
1049 					      NULL);
1050 	if (IS_ERR(bci->usb)) {
1051 		ret = PTR_ERR(bci->usb);
1052 		dev_err(&pdev->dev, "failed to register usb: %d\n", ret);
1053 		return ret;
1054 	}
1055 
1056 	ret = devm_request_threaded_irq(&pdev->dev, bci->irq_chg, NULL,
1057 			twl4030_charger_interrupt, IRQF_ONESHOT, pdev->name,
1058 			bci);
1059 	if (ret < 0) {
1060 		dev_err(&pdev->dev, "could not request irq %d, status %d\n",
1061 			bci->irq_chg, ret);
1062 		return ret;
1063 	}
1064 
1065 	ret = devm_request_threaded_irq(&pdev->dev, bci->irq_bci, NULL,
1066 			twl4030_bci_interrupt, IRQF_ONESHOT, pdev->name, bci);
1067 	if (ret < 0) {
1068 		dev_err(&pdev->dev, "could not request irq %d, status %d\n",
1069 			bci->irq_bci, ret);
1070 		return ret;
1071 	}
1072 
1073 	/* Enable interrupts now. */
1074 	reg = ~(u32)(TWL4030_ICHGLOW | TWL4030_ICHGEOC | TWL4030_TBATOR2 |
1075 		TWL4030_TBATOR1 | TWL4030_BATSTS);
1076 	ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg,
1077 			       TWL4030_INTERRUPTS_BCIIMR1A);
1078 	if (ret < 0) {
1079 		dev_err(&pdev->dev, "failed to unmask interrupts: %d\n", ret);
1080 		return ret;
1081 	}
1082 
1083 	reg = ~(u32)(TWL4030_VBATOV | TWL4030_VBUSOV | TWL4030_ACCHGOV);
1084 	ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg,
1085 			       TWL4030_INTERRUPTS_BCIIMR2A);
1086 	if (ret < 0)
1087 		dev_warn(&pdev->dev, "failed to unmask interrupts: %d\n", ret);
1088 
1089 	twl4030_charger_update_current(bci);
1090 	if (device_create_file(&bci->usb->dev, &dev_attr_mode))
1091 		dev_warn(&pdev->dev, "could not create sysfs file\n");
1092 	if (device_create_file(&bci->ac->dev, &dev_attr_mode))
1093 		dev_warn(&pdev->dev, "could not create sysfs file\n");
1094 
1095 	twl4030_charger_enable_ac(bci, true);
1096 	if (!IS_ERR_OR_NULL(bci->transceiver))
1097 		twl4030_bci_usb_ncb(&bci->usb_nb,
1098 				    bci->transceiver->last_event,
1099 				    NULL);
1100 	else
1101 		twl4030_charger_enable_usb(bci, false);
1102 	if (pdata)
1103 		twl4030_charger_enable_backup(pdata->bb_uvolt,
1104 					      pdata->bb_uamp);
1105 	else
1106 		twl4030_charger_enable_backup(0, 0);
1107 
1108 	return 0;
1109 }
1110 
twl4030_bci_remove(struct platform_device * pdev)1111 static void twl4030_bci_remove(struct platform_device *pdev)
1112 {
1113 	struct twl4030_bci *bci = platform_get_drvdata(pdev);
1114 
1115 	twl4030_charger_enable_ac(bci, false);
1116 	twl4030_charger_enable_usb(bci, false);
1117 	twl4030_charger_enable_backup(0, 0);
1118 
1119 	device_remove_file(&bci->usb->dev, &dev_attr_mode);
1120 	device_remove_file(&bci->ac->dev, &dev_attr_mode);
1121 	/* mask interrupts */
1122 	twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, 0xff,
1123 			 TWL4030_INTERRUPTS_BCIIMR1A);
1124 	twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, 0xff,
1125 			 TWL4030_INTERRUPTS_BCIIMR2A);
1126 }
1127 
1128 static const struct of_device_id twl_bci_of_match[] __maybe_unused = {
1129 	{.compatible = "ti,twl4030-bci", },
1130 	{ }
1131 };
1132 MODULE_DEVICE_TABLE(of, twl_bci_of_match);
1133 
1134 static struct platform_driver twl4030_bci_driver = {
1135 	.probe = twl4030_bci_probe,
1136 	.remove = twl4030_bci_remove,
1137 	.driver	= {
1138 		.name	= "twl4030_bci",
1139 		.of_match_table = of_match_ptr(twl_bci_of_match),
1140 	},
1141 };
1142 module_platform_driver(twl4030_bci_driver);
1143 
1144 MODULE_AUTHOR("Gražvydas Ignotas");
1145 MODULE_DESCRIPTION("TWL4030 Battery Charger Interface driver");
1146 MODULE_LICENSE("GPL");
1147 MODULE_ALIAS("platform:twl4030_bci");
1148