1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2011-2015, 2017, 2020, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/bitops.h>
7 #include <linux/delay.h>
8 #include <linux/err.h>
9 #include <linux/iio/consumer.h>
10 #include <linux/interrupt.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/of_device.h>
14 #include <linux/platform_device.h>
15 #include <linux/regmap.h>
16 #include <linux/thermal.h>
17 
18 #include "../thermal_hwmon.h"
19 
20 #define QPNP_TM_REG_DIG_MAJOR		0x01
21 #define QPNP_TM_REG_TYPE		0x04
22 #define QPNP_TM_REG_SUBTYPE		0x05
23 #define QPNP_TM_REG_STATUS		0x08
24 #define QPNP_TM_REG_SHUTDOWN_CTRL1	0x40
25 #define QPNP_TM_REG_ALARM_CTRL		0x46
26 
27 #define QPNP_TM_TYPE			0x09
28 #define QPNP_TM_SUBTYPE_GEN1		0x08
29 #define QPNP_TM_SUBTYPE_GEN2		0x09
30 
31 #define STATUS_GEN1_STAGE_MASK		GENMASK(1, 0)
32 #define STATUS_GEN2_STATE_MASK		GENMASK(6, 4)
33 #define STATUS_GEN2_STATE_SHIFT		4
34 
35 #define SHUTDOWN_CTRL1_OVERRIDE_S2	BIT(6)
36 #define SHUTDOWN_CTRL1_THRESHOLD_MASK	GENMASK(1, 0)
37 
38 #define SHUTDOWN_CTRL1_RATE_25HZ	BIT(3)
39 
40 #define ALARM_CTRL_FORCE_ENABLE		BIT(7)
41 
42 #define THRESH_COUNT			4
43 #define STAGE_COUNT			3
44 
45 /* Over-temperature trip point values in mC */
46 static const long temp_map_gen1[THRESH_COUNT][STAGE_COUNT] = {
47 	{ 105000, 125000, 145000 },
48 	{ 110000, 130000, 150000 },
49 	{ 115000, 135000, 155000 },
50 	{ 120000, 140000, 160000 },
51 };
52 
53 static const long temp_map_gen2_v1[THRESH_COUNT][STAGE_COUNT] = {
54 	{  90000, 110000, 140000 },
55 	{  95000, 115000, 145000 },
56 	{ 100000, 120000, 150000 },
57 	{ 105000, 125000, 155000 },
58 };
59 
60 #define TEMP_THRESH_STEP		5000 /* Threshold step: 5 C */
61 
62 #define THRESH_MIN			0
63 #define THRESH_MAX			3
64 
65 #define TEMP_STAGE_HYSTERESIS		2000
66 
67 /* Temperature in Milli Celsius reported during stage 0 if no ADC is present */
68 #define DEFAULT_TEMP			37000
69 
70 struct qpnp_tm_chip {
71 	struct regmap			*map;
72 	struct device			*dev;
73 	struct thermal_zone_device	*tz_dev;
74 	unsigned int			subtype;
75 	long				temp;
76 	unsigned int			thresh;
77 	unsigned int			stage;
78 	unsigned int			prev_stage;
79 	unsigned int			base;
80 	/* protects .thresh, .stage and chip registers */
81 	struct mutex			lock;
82 	bool				initialized;
83 
84 	struct iio_channel		*adc;
85 	const long			(*temp_map)[THRESH_COUNT][STAGE_COUNT];
86 };
87 
88 /* This array maps from GEN2 alarm state to GEN1 alarm stage */
89 static const unsigned int alarm_state_map[8] = {0, 1, 1, 2, 2, 3, 3, 3};
90 
91 static int qpnp_tm_read(struct qpnp_tm_chip *chip, u16 addr, u8 *data)
92 {
93 	unsigned int val;
94 	int ret;
95 
96 	ret = regmap_read(chip->map, chip->base + addr, &val);
97 	if (ret < 0)
98 		return ret;
99 
100 	*data = val;
101 	return 0;
102 }
103 
104 static int qpnp_tm_write(struct qpnp_tm_chip *chip, u16 addr, u8 data)
105 {
106 	return regmap_write(chip->map, chip->base + addr, data);
107 }
108 
109 /**
110  * qpnp_tm_decode_temp() - return temperature in mC corresponding to the
111  *		specified over-temperature stage
112  * @chip:		Pointer to the qpnp_tm chip
113  * @stage:		Over-temperature stage
114  *
115  * Return: temperature in mC
116  */
117 static long qpnp_tm_decode_temp(struct qpnp_tm_chip *chip, unsigned int stage)
118 {
119 	if (!chip->temp_map || chip->thresh >= THRESH_COUNT || stage == 0 ||
120 	    stage > STAGE_COUNT)
121 		return 0;
122 
123 	return (*chip->temp_map)[chip->thresh][stage - 1];
124 }
125 
126 /**
127  * qpnp_tm_get_temp_stage() - return over-temperature stage
128  * @chip:		Pointer to the qpnp_tm chip
129  *
130  * Return: stage (GEN1) or state (GEN2) on success, or errno on failure.
131  */
132 static int qpnp_tm_get_temp_stage(struct qpnp_tm_chip *chip)
133 {
134 	int ret;
135 	u8 reg = 0;
136 
137 	ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
138 	if (ret < 0)
139 		return ret;
140 
141 	if (chip->subtype == QPNP_TM_SUBTYPE_GEN1)
142 		ret = reg & STATUS_GEN1_STAGE_MASK;
143 	else
144 		ret = (reg & STATUS_GEN2_STATE_MASK) >> STATUS_GEN2_STATE_SHIFT;
145 
146 	return ret;
147 }
148 
149 /*
150  * This function updates the internal temp value based on the
151  * current thermal stage and threshold as well as the previous stage
152  */
153 static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
154 {
155 	unsigned int stage, stage_new, stage_old;
156 	int ret;
157 
158 	WARN_ON(!mutex_is_locked(&chip->lock));
159 
160 	ret = qpnp_tm_get_temp_stage(chip);
161 	if (ret < 0)
162 		return ret;
163 	stage = ret;
164 
165 	if (chip->subtype == QPNP_TM_SUBTYPE_GEN1) {
166 		stage_new = stage;
167 		stage_old = chip->stage;
168 	} else {
169 		stage_new = alarm_state_map[stage];
170 		stage_old = alarm_state_map[chip->stage];
171 	}
172 
173 	if (stage_new > stage_old) {
174 		/* increasing stage, use lower bound */
175 		chip->temp = qpnp_tm_decode_temp(chip, stage_new)
176 				+ TEMP_STAGE_HYSTERESIS;
177 	} else if (stage_new < stage_old) {
178 		/* decreasing stage, use upper bound */
179 		chip->temp = qpnp_tm_decode_temp(chip, stage_new + 1)
180 				- TEMP_STAGE_HYSTERESIS;
181 	}
182 
183 	chip->stage = stage;
184 
185 	return 0;
186 }
187 
188 static int qpnp_tm_get_temp(struct thermal_zone_device *tz, int *temp)
189 {
190 	struct qpnp_tm_chip *chip = tz->devdata;
191 	int ret, mili_celsius;
192 
193 	if (!temp)
194 		return -EINVAL;
195 
196 	if (!chip->initialized) {
197 		*temp = DEFAULT_TEMP;
198 		return 0;
199 	}
200 
201 	if (!chip->adc) {
202 		mutex_lock(&chip->lock);
203 		ret = qpnp_tm_update_temp_no_adc(chip);
204 		mutex_unlock(&chip->lock);
205 		if (ret < 0)
206 			return ret;
207 	} else {
208 		ret = iio_read_channel_processed(chip->adc, &mili_celsius);
209 		if (ret < 0)
210 			return ret;
211 
212 		chip->temp = mili_celsius;
213 	}
214 
215 	*temp = chip->temp;
216 
217 	return 0;
218 }
219 
220 static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
221 					     int temp)
222 {
223 	long stage2_threshold_min = (*chip->temp_map)[THRESH_MIN][1];
224 	long stage2_threshold_max = (*chip->temp_map)[THRESH_MAX][1];
225 	bool disable_s2_shutdown = false;
226 	u8 reg;
227 
228 	WARN_ON(!mutex_is_locked(&chip->lock));
229 
230 	/*
231 	 * Default: S2 and S3 shutdown enabled, thresholds at
232 	 * lowest threshold set, monitoring at 25Hz
233 	 */
234 	reg = SHUTDOWN_CTRL1_RATE_25HZ;
235 
236 	if (temp == THERMAL_TEMP_INVALID ||
237 	    temp < stage2_threshold_min) {
238 		chip->thresh = THRESH_MIN;
239 		goto skip;
240 	}
241 
242 	if (temp <= stage2_threshold_max) {
243 		chip->thresh = THRESH_MAX -
244 			((stage2_threshold_max - temp) /
245 			 TEMP_THRESH_STEP);
246 		disable_s2_shutdown = true;
247 	} else {
248 		chip->thresh = THRESH_MAX;
249 
250 		if (chip->adc)
251 			disable_s2_shutdown = true;
252 		else
253 			dev_warn(chip->dev,
254 				 "No ADC is configured and critical temperature %d mC is above the maximum stage 2 threshold of %ld mC! Configuring stage 2 shutdown at %ld mC.\n",
255 				 temp, stage2_threshold_max, stage2_threshold_max);
256 	}
257 
258 skip:
259 	reg |= chip->thresh;
260 	if (disable_s2_shutdown)
261 		reg |= SHUTDOWN_CTRL1_OVERRIDE_S2;
262 
263 	return qpnp_tm_write(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, reg);
264 }
265 
266 static int qpnp_tm_set_trip_temp(struct thermal_zone_device *tz, int trip_id, int temp)
267 {
268 	struct qpnp_tm_chip *chip = tz->devdata;
269 	struct thermal_trip trip;
270 	int ret;
271 
272 	ret = __thermal_zone_get_trip(chip->tz_dev, trip_id, &trip);
273 	if (ret)
274 		return ret;
275 
276 	if (trip.type != THERMAL_TRIP_CRITICAL)
277 		return 0;
278 
279 	mutex_lock(&chip->lock);
280 	ret = qpnp_tm_update_critical_trip_temp(chip, temp);
281 	mutex_unlock(&chip->lock);
282 
283 	return ret;
284 }
285 
286 static const struct thermal_zone_device_ops qpnp_tm_sensor_ops = {
287 	.get_temp = qpnp_tm_get_temp,
288 	.set_trip_temp = qpnp_tm_set_trip_temp,
289 };
290 
291 static irqreturn_t qpnp_tm_isr(int irq, void *data)
292 {
293 	struct qpnp_tm_chip *chip = data;
294 
295 	thermal_zone_device_update(chip->tz_dev, THERMAL_EVENT_UNSPECIFIED);
296 
297 	return IRQ_HANDLED;
298 }
299 
300 static int qpnp_tm_get_critical_trip_temp(struct qpnp_tm_chip *chip)
301 {
302 	struct thermal_trip trip;
303 	int i, ret;
304 
305 	for (i = 0; i < thermal_zone_get_num_trips(chip->tz_dev); i++) {
306 
307 		ret = thermal_zone_get_trip(chip->tz_dev, i, &trip);
308 		if (ret)
309 			continue;
310 
311 		if (trip.type == THERMAL_TRIP_CRITICAL)
312 			return trip.temperature;
313 	}
314 
315 	return THERMAL_TEMP_INVALID;
316 }
317 
318 /*
319  * This function initializes the internal temp value based on only the
320  * current thermal stage and threshold. Setup threshold control and
321  * disable shutdown override.
322  */
323 static int qpnp_tm_init(struct qpnp_tm_chip *chip)
324 {
325 	unsigned int stage;
326 	int ret;
327 	u8 reg = 0;
328 	int crit_temp;
329 
330 	mutex_lock(&chip->lock);
331 
332 	ret = qpnp_tm_read(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, &reg);
333 	if (ret < 0)
334 		goto out;
335 
336 	chip->thresh = reg & SHUTDOWN_CTRL1_THRESHOLD_MASK;
337 	chip->temp = DEFAULT_TEMP;
338 
339 	ret = qpnp_tm_get_temp_stage(chip);
340 	if (ret < 0)
341 		goto out;
342 	chip->stage = ret;
343 
344 	stage = chip->subtype == QPNP_TM_SUBTYPE_GEN1
345 		? chip->stage : alarm_state_map[chip->stage];
346 
347 	if (stage)
348 		chip->temp = qpnp_tm_decode_temp(chip, stage);
349 
350 	mutex_unlock(&chip->lock);
351 
352 	crit_temp = qpnp_tm_get_critical_trip_temp(chip);
353 
354 	mutex_lock(&chip->lock);
355 
356 	ret = qpnp_tm_update_critical_trip_temp(chip, crit_temp);
357 	if (ret < 0)
358 		goto out;
359 
360 	/* Enable the thermal alarm PMIC module in always-on mode. */
361 	reg = ALARM_CTRL_FORCE_ENABLE;
362 	ret = qpnp_tm_write(chip, QPNP_TM_REG_ALARM_CTRL, reg);
363 
364 	chip->initialized = true;
365 
366 out:
367 	mutex_unlock(&chip->lock);
368 	return ret;
369 }
370 
371 static int qpnp_tm_probe(struct platform_device *pdev)
372 {
373 	struct qpnp_tm_chip *chip;
374 	struct device_node *node;
375 	u8 type, subtype, dig_major;
376 	u32 res;
377 	int ret, irq;
378 
379 	node = pdev->dev.of_node;
380 
381 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
382 	if (!chip)
383 		return -ENOMEM;
384 
385 	dev_set_drvdata(&pdev->dev, chip);
386 	chip->dev = &pdev->dev;
387 
388 	mutex_init(&chip->lock);
389 
390 	chip->map = dev_get_regmap(pdev->dev.parent, NULL);
391 	if (!chip->map)
392 		return -ENXIO;
393 
394 	ret = of_property_read_u32(node, "reg", &res);
395 	if (ret < 0)
396 		return ret;
397 
398 	irq = platform_get_irq(pdev, 0);
399 	if (irq < 0)
400 		return irq;
401 
402 	/* ADC based measurements are optional */
403 	chip->adc = devm_iio_channel_get(&pdev->dev, "thermal");
404 	if (IS_ERR(chip->adc)) {
405 		ret = PTR_ERR(chip->adc);
406 		chip->adc = NULL;
407 		if (ret == -EPROBE_DEFER)
408 			return ret;
409 	}
410 
411 	chip->base = res;
412 
413 	ret = qpnp_tm_read(chip, QPNP_TM_REG_TYPE, &type);
414 	if (ret < 0) {
415 		dev_err(&pdev->dev, "could not read type\n");
416 		return ret;
417 	}
418 
419 	ret = qpnp_tm_read(chip, QPNP_TM_REG_SUBTYPE, &subtype);
420 	if (ret < 0) {
421 		dev_err(&pdev->dev, "could not read subtype\n");
422 		return ret;
423 	}
424 
425 	ret = qpnp_tm_read(chip, QPNP_TM_REG_DIG_MAJOR, &dig_major);
426 	if (ret < 0) {
427 		dev_err(&pdev->dev, "could not read dig_major\n");
428 		return ret;
429 	}
430 
431 	if (type != QPNP_TM_TYPE || (subtype != QPNP_TM_SUBTYPE_GEN1
432 				     && subtype != QPNP_TM_SUBTYPE_GEN2)) {
433 		dev_err(&pdev->dev, "invalid type 0x%02x or subtype 0x%02x\n",
434 			type, subtype);
435 		return -ENODEV;
436 	}
437 
438 	chip->subtype = subtype;
439 	if (subtype == QPNP_TM_SUBTYPE_GEN2 && dig_major >= 1)
440 		chip->temp_map = &temp_map_gen2_v1;
441 	else
442 		chip->temp_map = &temp_map_gen1;
443 
444 	/*
445 	 * Register the sensor before initializing the hardware to be able to
446 	 * read the trip points. get_temp() returns the default temperature
447 	 * before the hardware initialization is completed.
448 	 */
449 	chip->tz_dev = devm_thermal_of_zone_register(
450 		&pdev->dev, 0, chip, &qpnp_tm_sensor_ops);
451 	if (IS_ERR(chip->tz_dev)) {
452 		dev_err(&pdev->dev, "failed to register sensor\n");
453 		return PTR_ERR(chip->tz_dev);
454 	}
455 
456 	ret = qpnp_tm_init(chip);
457 	if (ret < 0) {
458 		dev_err(&pdev->dev, "init failed\n");
459 		return ret;
460 	}
461 
462 	if (devm_thermal_add_hwmon_sysfs(chip->tz_dev))
463 		dev_warn(&pdev->dev,
464 			 "Failed to add hwmon sysfs attributes\n");
465 
466 	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, qpnp_tm_isr,
467 					IRQF_ONESHOT, node->name, chip);
468 	if (ret < 0)
469 		return ret;
470 
471 	thermal_zone_device_update(chip->tz_dev, THERMAL_EVENT_UNSPECIFIED);
472 
473 	return 0;
474 }
475 
476 static const struct of_device_id qpnp_tm_match_table[] = {
477 	{ .compatible = "qcom,spmi-temp-alarm" },
478 	{ }
479 };
480 MODULE_DEVICE_TABLE(of, qpnp_tm_match_table);
481 
482 static struct platform_driver qpnp_tm_driver = {
483 	.driver = {
484 		.name = "spmi-temp-alarm",
485 		.of_match_table = qpnp_tm_match_table,
486 	},
487 	.probe  = qpnp_tm_probe,
488 };
489 module_platform_driver(qpnp_tm_driver);
490 
491 MODULE_ALIAS("platform:spmi-temp-alarm");
492 MODULE_DESCRIPTION("QPNP PMIC Temperature Alarm driver");
493 MODULE_LICENSE("GPL v2");
494