xref: /openbmc/linux/drivers/power/supply/da9150-fg.c (revision a34a9f1a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DA9150 Fuel-Gauge Driver
4  *
5  * Copyright (c) 2015 Dialog Semiconductor
6  *
7  * Author: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/of.h>
14 #include <linux/slab.h>
15 #include <linux/interrupt.h>
16 #include <linux/delay.h>
17 #include <linux/power_supply.h>
18 #include <linux/list.h>
19 #include <asm/div64.h>
20 #include <linux/mfd/da9150/core.h>
21 #include <linux/mfd/da9150/registers.h>
22 #include <linux/devm-helpers.h>
23 
24 /* Core2Wire */
25 #define DA9150_QIF_READ		(0x0 << 7)
26 #define DA9150_QIF_WRITE	(0x1 << 7)
27 #define DA9150_QIF_CODE_MASK	0x7F
28 
29 #define DA9150_QIF_BYTE_SIZE	8
30 #define DA9150_QIF_BYTE_MASK	0xFF
31 #define DA9150_QIF_SHORT_SIZE	2
32 #define DA9150_QIF_LONG_SIZE	4
33 
34 /* QIF Codes */
35 #define DA9150_QIF_UAVG			6
36 #define DA9150_QIF_UAVG_SIZE		DA9150_QIF_LONG_SIZE
37 #define DA9150_QIF_IAVG			8
38 #define DA9150_QIF_IAVG_SIZE		DA9150_QIF_LONG_SIZE
39 #define DA9150_QIF_NTCAVG		12
40 #define DA9150_QIF_NTCAVG_SIZE		DA9150_QIF_LONG_SIZE
41 #define DA9150_QIF_SHUNT_VAL		36
42 #define DA9150_QIF_SHUNT_VAL_SIZE	DA9150_QIF_SHORT_SIZE
43 #define DA9150_QIF_SD_GAIN		38
44 #define DA9150_QIF_SD_GAIN_SIZE		DA9150_QIF_LONG_SIZE
45 #define DA9150_QIF_FCC_MAH		40
46 #define DA9150_QIF_FCC_MAH_SIZE		DA9150_QIF_SHORT_SIZE
47 #define DA9150_QIF_SOC_PCT		43
48 #define DA9150_QIF_SOC_PCT_SIZE		DA9150_QIF_SHORT_SIZE
49 #define DA9150_QIF_CHARGE_LIMIT		44
50 #define DA9150_QIF_CHARGE_LIMIT_SIZE	DA9150_QIF_SHORT_SIZE
51 #define DA9150_QIF_DISCHARGE_LIMIT	45
52 #define DA9150_QIF_DISCHARGE_LIMIT_SIZE	DA9150_QIF_SHORT_SIZE
53 #define DA9150_QIF_FW_MAIN_VER		118
54 #define DA9150_QIF_FW_MAIN_VER_SIZE	DA9150_QIF_SHORT_SIZE
55 #define DA9150_QIF_E_FG_STATUS		126
56 #define DA9150_QIF_E_FG_STATUS_SIZE	DA9150_QIF_SHORT_SIZE
57 #define DA9150_QIF_SYNC			127
58 #define DA9150_QIF_SYNC_SIZE		DA9150_QIF_SHORT_SIZE
59 #define DA9150_QIF_MAX_CODES		128
60 
61 /* QIF Sync Timeout */
62 #define DA9150_QIF_SYNC_TIMEOUT		1000
63 #define DA9150_QIF_SYNC_RETRIES		10
64 
65 /* QIF E_FG_STATUS */
66 #define DA9150_FG_IRQ_LOW_SOC_MASK	(1 << 0)
67 #define DA9150_FG_IRQ_HIGH_SOC_MASK	(1 << 1)
68 #define DA9150_FG_IRQ_SOC_MASK	\
69 	(DA9150_FG_IRQ_LOW_SOC_MASK | DA9150_FG_IRQ_HIGH_SOC_MASK)
70 
71 /* Private data */
72 struct da9150_fg {
73 	struct da9150 *da9150;
74 	struct device *dev;
75 
76 	struct mutex io_lock;
77 
78 	struct power_supply *battery;
79 	struct delayed_work work;
80 	u32 interval;
81 
82 	int warn_soc;
83 	int crit_soc;
84 	int soc;
85 };
86 
87 /* Battery Properties */
88 static u32 da9150_fg_read_attr(struct da9150_fg *fg, u8 code, u8 size)
89 
90 {
91 	u8 buf[DA9150_QIF_LONG_SIZE];
92 	u8 read_addr;
93 	u32 res = 0;
94 	int i;
95 
96 	/* Set QIF code (READ mode) */
97 	read_addr = (code & DA9150_QIF_CODE_MASK) | DA9150_QIF_READ;
98 
99 	da9150_read_qif(fg->da9150, read_addr, size, buf);
100 	for (i = 0; i < size; ++i)
101 		res |= (buf[i] << (i * DA9150_QIF_BYTE_SIZE));
102 
103 	return res;
104 }
105 
106 static void da9150_fg_write_attr(struct da9150_fg *fg, u8 code, u8 size,
107 				 u32 val)
108 
109 {
110 	u8 buf[DA9150_QIF_LONG_SIZE];
111 	u8 write_addr;
112 	int i;
113 
114 	/* Set QIF code (WRITE mode) */
115 	write_addr = (code & DA9150_QIF_CODE_MASK) | DA9150_QIF_WRITE;
116 
117 	for (i = 0; i < size; ++i) {
118 		buf[i] = (val >> (i * DA9150_QIF_BYTE_SIZE)) &
119 			 DA9150_QIF_BYTE_MASK;
120 	}
121 	da9150_write_qif(fg->da9150, write_addr, size, buf);
122 }
123 
124 /* Trigger QIF Sync to update QIF readable data */
125 static void da9150_fg_read_sync_start(struct da9150_fg *fg)
126 {
127 	int i = 0;
128 	u32 res = 0;
129 
130 	mutex_lock(&fg->io_lock);
131 
132 	/* Check if QIF sync already requested, and write to sync if not */
133 	res = da9150_fg_read_attr(fg, DA9150_QIF_SYNC,
134 				  DA9150_QIF_SYNC_SIZE);
135 	if (res > 0)
136 		da9150_fg_write_attr(fg, DA9150_QIF_SYNC,
137 				     DA9150_QIF_SYNC_SIZE, 0);
138 
139 	/* Wait for sync to complete */
140 	res = 0;
141 	while ((res == 0) && (i++ < DA9150_QIF_SYNC_RETRIES)) {
142 		usleep_range(DA9150_QIF_SYNC_TIMEOUT,
143 			     DA9150_QIF_SYNC_TIMEOUT * 2);
144 		res = da9150_fg_read_attr(fg, DA9150_QIF_SYNC,
145 					  DA9150_QIF_SYNC_SIZE);
146 	}
147 
148 	/* Check if sync completed */
149 	if (res == 0)
150 		dev_err(fg->dev, "Failed to perform QIF read sync!\n");
151 }
152 
153 /*
154  * Should always be called after QIF sync read has been performed, and all
155  * attributes required have been accessed.
156  */
157 static inline void da9150_fg_read_sync_end(struct da9150_fg *fg)
158 {
159 	mutex_unlock(&fg->io_lock);
160 }
161 
162 /* Sync read of single QIF attribute */
163 static u32 da9150_fg_read_attr_sync(struct da9150_fg *fg, u8 code, u8 size)
164 {
165 	u32 val;
166 
167 	da9150_fg_read_sync_start(fg);
168 	val = da9150_fg_read_attr(fg, code, size);
169 	da9150_fg_read_sync_end(fg);
170 
171 	return val;
172 }
173 
174 /* Wait for QIF Sync, write QIF data and wait for ack */
175 static void da9150_fg_write_attr_sync(struct da9150_fg *fg, u8 code, u8 size,
176 				      u32 val)
177 {
178 	int i = 0;
179 	u32 res = 0, sync_val;
180 
181 	mutex_lock(&fg->io_lock);
182 
183 	/* Check if QIF sync already requested */
184 	res = da9150_fg_read_attr(fg, DA9150_QIF_SYNC,
185 				  DA9150_QIF_SYNC_SIZE);
186 
187 	/* Wait for an existing sync to complete */
188 	while ((res == 0) && (i++ < DA9150_QIF_SYNC_RETRIES)) {
189 		usleep_range(DA9150_QIF_SYNC_TIMEOUT,
190 			     DA9150_QIF_SYNC_TIMEOUT * 2);
191 		res = da9150_fg_read_attr(fg, DA9150_QIF_SYNC,
192 					  DA9150_QIF_SYNC_SIZE);
193 	}
194 
195 	if (res == 0) {
196 		dev_err(fg->dev, "Timeout waiting for existing QIF sync!\n");
197 		mutex_unlock(&fg->io_lock);
198 		return;
199 	}
200 
201 	/* Write value for QIF code */
202 	da9150_fg_write_attr(fg, code, size, val);
203 
204 	/* Wait for write acknowledgment */
205 	i = 0;
206 	sync_val = res;
207 	while ((res == sync_val) && (i++ < DA9150_QIF_SYNC_RETRIES)) {
208 		usleep_range(DA9150_QIF_SYNC_TIMEOUT,
209 			     DA9150_QIF_SYNC_TIMEOUT * 2);
210 		res = da9150_fg_read_attr(fg, DA9150_QIF_SYNC,
211 					  DA9150_QIF_SYNC_SIZE);
212 	}
213 
214 	mutex_unlock(&fg->io_lock);
215 
216 	/* Check write was actually successful */
217 	if (res != (sync_val + 1))
218 		dev_err(fg->dev, "Error performing QIF sync write for code %d\n",
219 			code);
220 }
221 
222 /* Power Supply attributes */
223 static int da9150_fg_capacity(struct da9150_fg *fg,
224 			      union power_supply_propval *val)
225 {
226 	val->intval = da9150_fg_read_attr_sync(fg, DA9150_QIF_SOC_PCT,
227 					       DA9150_QIF_SOC_PCT_SIZE);
228 
229 	if (val->intval > 100)
230 		val->intval = 100;
231 
232 	return 0;
233 }
234 
235 static int da9150_fg_current_avg(struct da9150_fg *fg,
236 				 union power_supply_propval *val)
237 {
238 	u32 iavg, sd_gain, shunt_val;
239 	u64 div, res;
240 
241 	da9150_fg_read_sync_start(fg);
242 	iavg = da9150_fg_read_attr(fg, DA9150_QIF_IAVG,
243 				   DA9150_QIF_IAVG_SIZE);
244 	shunt_val = da9150_fg_read_attr(fg, DA9150_QIF_SHUNT_VAL,
245 					DA9150_QIF_SHUNT_VAL_SIZE);
246 	sd_gain = da9150_fg_read_attr(fg, DA9150_QIF_SD_GAIN,
247 				      DA9150_QIF_SD_GAIN_SIZE);
248 	da9150_fg_read_sync_end(fg);
249 
250 	div = (u64) (sd_gain * shunt_val * 65536ULL);
251 	do_div(div, 1000000);
252 	res = (u64) (iavg * 1000000ULL);
253 	do_div(res, div);
254 
255 	val->intval = (int) res;
256 
257 	return 0;
258 }
259 
260 static int da9150_fg_voltage_avg(struct da9150_fg *fg,
261 				 union power_supply_propval *val)
262 {
263 	u64 res;
264 
265 	val->intval = da9150_fg_read_attr_sync(fg, DA9150_QIF_UAVG,
266 					       DA9150_QIF_UAVG_SIZE);
267 
268 	res = (u64) (val->intval * 186ULL);
269 	do_div(res, 10000);
270 	val->intval = (int) res;
271 
272 	return 0;
273 }
274 
275 static int da9150_fg_charge_full(struct da9150_fg *fg,
276 				 union power_supply_propval *val)
277 {
278 	val->intval = da9150_fg_read_attr_sync(fg, DA9150_QIF_FCC_MAH,
279 					       DA9150_QIF_FCC_MAH_SIZE);
280 
281 	val->intval = val->intval * 1000;
282 
283 	return 0;
284 }
285 
286 /*
287  * Temperature reading from device is only valid if battery/system provides
288  * valid NTC to associated pin of DA9150 chip.
289  */
290 static int da9150_fg_temp(struct da9150_fg *fg,
291 			  union power_supply_propval *val)
292 {
293 	val->intval = da9150_fg_read_attr_sync(fg, DA9150_QIF_NTCAVG,
294 					       DA9150_QIF_NTCAVG_SIZE);
295 
296 	val->intval = (val->intval * 10) / 1048576;
297 
298 	return 0;
299 }
300 
301 static enum power_supply_property da9150_fg_props[] = {
302 	POWER_SUPPLY_PROP_CAPACITY,
303 	POWER_SUPPLY_PROP_CURRENT_AVG,
304 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
305 	POWER_SUPPLY_PROP_CHARGE_FULL,
306 	POWER_SUPPLY_PROP_TEMP,
307 };
308 
309 static int da9150_fg_get_prop(struct power_supply *psy,
310 			      enum power_supply_property psp,
311 			      union power_supply_propval *val)
312 {
313 	struct da9150_fg *fg = dev_get_drvdata(psy->dev.parent);
314 	int ret;
315 
316 	switch (psp) {
317 	case POWER_SUPPLY_PROP_CAPACITY:
318 		ret = da9150_fg_capacity(fg, val);
319 		break;
320 	case POWER_SUPPLY_PROP_CURRENT_AVG:
321 		ret = da9150_fg_current_avg(fg, val);
322 		break;
323 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
324 		ret = da9150_fg_voltage_avg(fg, val);
325 		break;
326 	case POWER_SUPPLY_PROP_CHARGE_FULL:
327 		ret = da9150_fg_charge_full(fg, val);
328 		break;
329 	case POWER_SUPPLY_PROP_TEMP:
330 		ret = da9150_fg_temp(fg, val);
331 		break;
332 	default:
333 		ret = -EINVAL;
334 		break;
335 	}
336 
337 	return ret;
338 }
339 
340 /* Repeated SOC check */
341 static bool da9150_fg_soc_changed(struct da9150_fg *fg)
342 {
343 	union power_supply_propval val;
344 
345 	da9150_fg_capacity(fg, &val);
346 	if (val.intval != fg->soc) {
347 		fg->soc = val.intval;
348 		return true;
349 	}
350 
351 	return false;
352 }
353 
354 static void da9150_fg_work(struct work_struct *work)
355 {
356 	struct da9150_fg *fg = container_of(work, struct da9150_fg, work.work);
357 
358 	/* Report if SOC has changed */
359 	if (da9150_fg_soc_changed(fg))
360 		power_supply_changed(fg->battery);
361 
362 	schedule_delayed_work(&fg->work, msecs_to_jiffies(fg->interval));
363 }
364 
365 /* SOC level event configuration */
366 static void da9150_fg_soc_event_config(struct da9150_fg *fg)
367 {
368 	int soc;
369 
370 	soc = da9150_fg_read_attr_sync(fg, DA9150_QIF_SOC_PCT,
371 				       DA9150_QIF_SOC_PCT_SIZE);
372 
373 	if (soc > fg->warn_soc) {
374 		/* If SOC > warn level, set discharge warn level event */
375 		da9150_fg_write_attr_sync(fg, DA9150_QIF_DISCHARGE_LIMIT,
376 					  DA9150_QIF_DISCHARGE_LIMIT_SIZE,
377 					  fg->warn_soc + 1);
378 	} else if ((soc <= fg->warn_soc) && (soc > fg->crit_soc)) {
379 		/*
380 		 * If SOC <= warn level, set discharge crit level event,
381 		 * and set charge warn level event.
382 		 */
383 		da9150_fg_write_attr_sync(fg, DA9150_QIF_DISCHARGE_LIMIT,
384 					  DA9150_QIF_DISCHARGE_LIMIT_SIZE,
385 					  fg->crit_soc + 1);
386 
387 		da9150_fg_write_attr_sync(fg, DA9150_QIF_CHARGE_LIMIT,
388 					  DA9150_QIF_CHARGE_LIMIT_SIZE,
389 					  fg->warn_soc);
390 	} else if (soc <= fg->crit_soc) {
391 		/* If SOC <= crit level, set charge crit level event */
392 		da9150_fg_write_attr_sync(fg, DA9150_QIF_CHARGE_LIMIT,
393 					  DA9150_QIF_CHARGE_LIMIT_SIZE,
394 					  fg->crit_soc);
395 	}
396 }
397 
398 static irqreturn_t da9150_fg_irq(int irq, void *data)
399 {
400 	struct da9150_fg *fg = data;
401 	u32 e_fg_status;
402 
403 	/* Read FG IRQ status info */
404 	e_fg_status = da9150_fg_read_attr(fg, DA9150_QIF_E_FG_STATUS,
405 					  DA9150_QIF_E_FG_STATUS_SIZE);
406 
407 	/* Handle warning/critical threhold events */
408 	if (e_fg_status & DA9150_FG_IRQ_SOC_MASK)
409 		da9150_fg_soc_event_config(fg);
410 
411 	/* Clear any FG IRQs */
412 	da9150_fg_write_attr(fg, DA9150_QIF_E_FG_STATUS,
413 			     DA9150_QIF_E_FG_STATUS_SIZE, e_fg_status);
414 
415 	return IRQ_HANDLED;
416 }
417 
418 static struct da9150_fg_pdata *da9150_fg_dt_pdata(struct device *dev)
419 {
420 	struct device_node *fg_node = dev->of_node;
421 	struct da9150_fg_pdata *pdata;
422 
423 	pdata = devm_kzalloc(dev, sizeof(struct da9150_fg_pdata), GFP_KERNEL);
424 	if (!pdata)
425 		return NULL;
426 
427 	of_property_read_u32(fg_node, "dlg,update-interval",
428 			     &pdata->update_interval);
429 	of_property_read_u8(fg_node, "dlg,warn-soc-level",
430 			    &pdata->warn_soc_lvl);
431 	of_property_read_u8(fg_node, "dlg,crit-soc-level",
432 			    &pdata->crit_soc_lvl);
433 
434 	return pdata;
435 }
436 
437 static const struct power_supply_desc fg_desc = {
438 	.name		= "da9150-fg",
439 	.type		= POWER_SUPPLY_TYPE_BATTERY,
440 	.properties	= da9150_fg_props,
441 	.num_properties	= ARRAY_SIZE(da9150_fg_props),
442 	.get_property	= da9150_fg_get_prop,
443 };
444 
445 static int da9150_fg_probe(struct platform_device *pdev)
446 {
447 	struct device *dev = &pdev->dev;
448 	struct da9150 *da9150 = dev_get_drvdata(dev->parent);
449 	struct da9150_fg_pdata *fg_pdata = dev_get_platdata(dev);
450 	struct da9150_fg *fg;
451 	int ver, irq, ret = 0;
452 
453 	fg = devm_kzalloc(dev, sizeof(*fg), GFP_KERNEL);
454 	if (fg == NULL)
455 		return -ENOMEM;
456 
457 	platform_set_drvdata(pdev, fg);
458 	fg->da9150 = da9150;
459 	fg->dev = dev;
460 
461 	mutex_init(&fg->io_lock);
462 
463 	/* Enable QIF */
464 	da9150_set_bits(da9150, DA9150_CORE2WIRE_CTRL_A, DA9150_FG_QIF_EN_MASK,
465 			DA9150_FG_QIF_EN_MASK);
466 
467 	fg->battery = devm_power_supply_register(dev, &fg_desc, NULL);
468 	if (IS_ERR(fg->battery)) {
469 		ret = PTR_ERR(fg->battery);
470 		return ret;
471 	}
472 
473 	ver = da9150_fg_read_attr(fg, DA9150_QIF_FW_MAIN_VER,
474 				  DA9150_QIF_FW_MAIN_VER_SIZE);
475 	dev_info(dev, "Version: 0x%x\n", ver);
476 
477 	/* Handle DT data if provided */
478 	if (dev->of_node) {
479 		fg_pdata = da9150_fg_dt_pdata(dev);
480 		dev->platform_data = fg_pdata;
481 	}
482 
483 	/* Handle any pdata provided */
484 	if (fg_pdata) {
485 		fg->interval = fg_pdata->update_interval;
486 
487 		if (fg_pdata->warn_soc_lvl > 100)
488 			dev_warn(dev, "Invalid SOC warning level provided, Ignoring");
489 		else
490 			fg->warn_soc = fg_pdata->warn_soc_lvl;
491 
492 		if ((fg_pdata->crit_soc_lvl > 100) ||
493 		    (fg_pdata->crit_soc_lvl >= fg_pdata->warn_soc_lvl))
494 			dev_warn(dev, "Invalid SOC critical level provided, Ignoring");
495 		else
496 			fg->crit_soc = fg_pdata->crit_soc_lvl;
497 
498 
499 	}
500 
501 	/* Configure initial SOC level events */
502 	da9150_fg_soc_event_config(fg);
503 
504 	/*
505 	 * If an interval period has been provided then setup repeating
506 	 * work for reporting data updates.
507 	 */
508 	if (fg->interval) {
509 		ret = devm_delayed_work_autocancel(dev, &fg->work,
510 						   da9150_fg_work);
511 		if (ret) {
512 			dev_err(dev, "Failed to init work\n");
513 			return ret;
514 		}
515 
516 		schedule_delayed_work(&fg->work,
517 				      msecs_to_jiffies(fg->interval));
518 	}
519 
520 	/* Register IRQ */
521 	irq = platform_get_irq_byname(pdev, "FG");
522 	if (irq < 0)
523 		return irq;
524 
525 	ret = devm_request_threaded_irq(dev, irq, NULL, da9150_fg_irq,
526 					IRQF_ONESHOT, "FG", fg);
527 	if (ret) {
528 		dev_err(dev, "Failed to request IRQ %d: %d\n", irq, ret);
529 		return ret;
530 	}
531 
532 	return 0;
533 }
534 
535 static int da9150_fg_resume(struct platform_device *pdev)
536 {
537 	struct da9150_fg *fg = platform_get_drvdata(pdev);
538 
539 	/*
540 	 * Trigger SOC check to happen now so as to indicate any value change
541 	 * since last check before suspend.
542 	 */
543 	if (fg->interval)
544 		flush_delayed_work(&fg->work);
545 
546 	return 0;
547 }
548 
549 static struct platform_driver da9150_fg_driver = {
550 	.driver = {
551 		.name = "da9150-fuel-gauge",
552 	},
553 	.probe = da9150_fg_probe,
554 	.resume = da9150_fg_resume,
555 };
556 
557 module_platform_driver(da9150_fg_driver);
558 
559 MODULE_DESCRIPTION("Fuel-Gauge Driver for DA9150");
560 MODULE_AUTHOR("Adam Thomson <Adam.Thomson.Opensource@diasemi.com>");
561 MODULE_LICENSE("GPL");
562