1 /*
2  *  R-Car THS/TSC thermal sensor driver
3  *
4  * Copyright (C) 2012 Renesas Solutions Corp.
5  * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; version 2 of the License.
10  *
11  *  This program is distributed in the hope that it will be useful, but
12  *  WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  *  General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License along
17  *  with this program; if not, write to the Free Software Foundation, Inc.,
18  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
19  */
20 #include <linux/delay.h>
21 #include <linux/err.h>
22 #include <linux/irq.h>
23 #include <linux/interrupt.h>
24 #include <linux/io.h>
25 #include <linux/module.h>
26 #include <linux/of_device.h>
27 #include <linux/platform_device.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/reboot.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <linux/thermal.h>
33 
34 #include "thermal_hwmon.h"
35 
36 #define IDLE_INTERVAL	5000
37 
38 #define COMMON_STR	0x00
39 #define COMMON_ENR	0x04
40 #define COMMON_INTMSK	0x0c
41 
42 #define REG_POSNEG	0x20
43 #define REG_FILONOFF	0x28
44 #define REG_THSCR	0x2c
45 #define REG_THSSR	0x30
46 #define REG_INTCTRL	0x34
47 
48 /* THSCR */
49 #define CPCTL	(1 << 12)
50 
51 /* THSSR */
52 #define CTEMP	0x3f
53 
54 struct rcar_thermal_common {
55 	void __iomem *base;
56 	struct device *dev;
57 	struct list_head head;
58 	spinlock_t lock;
59 };
60 
61 struct rcar_thermal_chip {
62 	unsigned int use_of_thermal : 1;
63 	unsigned int has_filonoff : 1;
64 	unsigned int irq_per_ch : 1;
65 	unsigned int needs_suspend_resume : 1;
66 	unsigned int nirqs;
67 };
68 
69 static const struct rcar_thermal_chip rcar_thermal = {
70 	.use_of_thermal = 0,
71 	.has_filonoff = 1,
72 	.irq_per_ch = 0,
73 	.needs_suspend_resume = 0,
74 	.nirqs = 1,
75 };
76 
77 static const struct rcar_thermal_chip rcar_gen2_thermal = {
78 	.use_of_thermal = 1,
79 	.has_filonoff = 1,
80 	.irq_per_ch = 0,
81 	.needs_suspend_resume = 0,
82 	.nirqs = 1,
83 };
84 
85 static const struct rcar_thermal_chip rcar_gen3_thermal = {
86 	.use_of_thermal = 1,
87 	.has_filonoff = 0,
88 	.irq_per_ch = 1,
89 	.needs_suspend_resume = 1,
90 	/*
91 	 * The Gen3 chip has 3 interrupts, but this driver uses only 2
92 	 * interrupts to detect a temperature change, rise or fall.
93 	 */
94 	.nirqs = 2,
95 };
96 
97 struct rcar_thermal_priv {
98 	void __iomem *base;
99 	struct rcar_thermal_common *common;
100 	struct thermal_zone_device *zone;
101 	const struct rcar_thermal_chip *chip;
102 	struct delayed_work work;
103 	struct mutex lock;
104 	struct list_head list;
105 	int id;
106 	u32 ctemp;
107 };
108 
109 #define rcar_thermal_for_each_priv(pos, common)	\
110 	list_for_each_entry(pos, &common->head, list)
111 
112 #define MCELSIUS(temp)			((temp) * 1000)
113 #define rcar_zone_to_priv(zone)		((zone)->devdata)
114 #define rcar_priv_to_dev(priv)		((priv)->common->dev)
115 #define rcar_has_irq_support(priv)	((priv)->common->base)
116 #define rcar_id_to_shift(priv)		((priv)->id * 8)
117 
118 static const struct of_device_id rcar_thermal_dt_ids[] = {
119 	{
120 		.compatible = "renesas,rcar-thermal",
121 		.data = &rcar_thermal,
122 	},
123 	{
124 		.compatible = "renesas,rcar-gen2-thermal",
125 		 .data = &rcar_gen2_thermal,
126 	},
127 	{
128 		.compatible = "renesas,thermal-r8a77995",
129 		.data = &rcar_gen3_thermal,
130 	},
131 	{},
132 };
133 MODULE_DEVICE_TABLE(of, rcar_thermal_dt_ids);
134 
135 /*
136  *		basic functions
137  */
138 #define rcar_thermal_common_read(c, r) \
139 	_rcar_thermal_common_read(c, COMMON_ ##r)
140 static u32 _rcar_thermal_common_read(struct rcar_thermal_common *common,
141 				     u32 reg)
142 {
143 	return ioread32(common->base + reg);
144 }
145 
146 #define rcar_thermal_common_write(c, r, d) \
147 	_rcar_thermal_common_write(c, COMMON_ ##r, d)
148 static void _rcar_thermal_common_write(struct rcar_thermal_common *common,
149 				       u32 reg, u32 data)
150 {
151 	iowrite32(data, common->base + reg);
152 }
153 
154 #define rcar_thermal_common_bset(c, r, m, d) \
155 	_rcar_thermal_common_bset(c, COMMON_ ##r, m, d)
156 static void _rcar_thermal_common_bset(struct rcar_thermal_common *common,
157 				      u32 reg, u32 mask, u32 data)
158 {
159 	u32 val;
160 
161 	val = ioread32(common->base + reg);
162 	val &= ~mask;
163 	val |= (data & mask);
164 	iowrite32(val, common->base + reg);
165 }
166 
167 #define rcar_thermal_read(p, r) _rcar_thermal_read(p, REG_ ##r)
168 static u32 _rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg)
169 {
170 	return ioread32(priv->base + reg);
171 }
172 
173 #define rcar_thermal_write(p, r, d) _rcar_thermal_write(p, REG_ ##r, d)
174 static void _rcar_thermal_write(struct rcar_thermal_priv *priv,
175 				u32 reg, u32 data)
176 {
177 	iowrite32(data, priv->base + reg);
178 }
179 
180 #define rcar_thermal_bset(p, r, m, d) _rcar_thermal_bset(p, REG_ ##r, m, d)
181 static void _rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg,
182 			       u32 mask, u32 data)
183 {
184 	u32 val;
185 
186 	val = ioread32(priv->base + reg);
187 	val &= ~mask;
188 	val |= (data & mask);
189 	iowrite32(val, priv->base + reg);
190 }
191 
192 /*
193  *		zone device functions
194  */
195 static int rcar_thermal_update_temp(struct rcar_thermal_priv *priv)
196 {
197 	struct device *dev = rcar_priv_to_dev(priv);
198 	int i;
199 	u32 ctemp, old, new;
200 	int ret = -EINVAL;
201 
202 	mutex_lock(&priv->lock);
203 
204 	/*
205 	 * TSC decides a value of CPTAP automatically,
206 	 * and this is the conditions which validate interrupt.
207 	 */
208 	rcar_thermal_bset(priv, THSCR, CPCTL, CPCTL);
209 
210 	ctemp = 0;
211 	old = ~0;
212 	for (i = 0; i < 128; i++) {
213 		/*
214 		 * we need to wait 300us after changing comparator offset
215 		 * to get stable temperature.
216 		 * see "Usage Notes" on datasheet
217 		 */
218 		udelay(300);
219 
220 		new = rcar_thermal_read(priv, THSSR) & CTEMP;
221 		if (new == old) {
222 			ctemp = new;
223 			break;
224 		}
225 		old = new;
226 	}
227 
228 	if (!ctemp) {
229 		dev_err(dev, "thermal sensor was broken\n");
230 		goto err_out_unlock;
231 	}
232 
233 	/*
234 	 * enable IRQ
235 	 */
236 	if (rcar_has_irq_support(priv)) {
237 		if (priv->chip->has_filonoff)
238 			rcar_thermal_write(priv, FILONOFF, 0);
239 
240 		/* enable Rising/Falling edge interrupt */
241 		rcar_thermal_write(priv, POSNEG,  0x1);
242 		rcar_thermal_write(priv, INTCTRL, (((ctemp - 0) << 8) |
243 						   ((ctemp - 1) << 0)));
244 	}
245 
246 	dev_dbg(dev, "thermal%d  %d -> %d\n", priv->id, priv->ctemp, ctemp);
247 
248 	priv->ctemp = ctemp;
249 	ret = 0;
250 err_out_unlock:
251 	mutex_unlock(&priv->lock);
252 	return ret;
253 }
254 
255 static int rcar_thermal_get_current_temp(struct rcar_thermal_priv *priv,
256 					 int *temp)
257 {
258 	int tmp;
259 	int ret;
260 
261 	ret = rcar_thermal_update_temp(priv);
262 	if (ret < 0)
263 		return ret;
264 
265 	mutex_lock(&priv->lock);
266 	tmp =  MCELSIUS((priv->ctemp * 5) - 65);
267 	mutex_unlock(&priv->lock);
268 
269 	if ((tmp < MCELSIUS(-45)) || (tmp > MCELSIUS(125))) {
270 		struct device *dev = rcar_priv_to_dev(priv);
271 
272 		dev_err(dev, "it couldn't measure temperature correctly\n");
273 		return -EIO;
274 	}
275 
276 	*temp = tmp;
277 
278 	return 0;
279 }
280 
281 static int rcar_thermal_of_get_temp(void *data, int *temp)
282 {
283 	struct rcar_thermal_priv *priv = data;
284 
285 	return rcar_thermal_get_current_temp(priv, temp);
286 }
287 
288 static int rcar_thermal_get_temp(struct thermal_zone_device *zone, int *temp)
289 {
290 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
291 
292 	return rcar_thermal_get_current_temp(priv, temp);
293 }
294 
295 static int rcar_thermal_get_trip_type(struct thermal_zone_device *zone,
296 				      int trip, enum thermal_trip_type *type)
297 {
298 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
299 	struct device *dev = rcar_priv_to_dev(priv);
300 
301 	/* see rcar_thermal_get_temp() */
302 	switch (trip) {
303 	case 0: /* +90 <= temp */
304 		*type = THERMAL_TRIP_CRITICAL;
305 		break;
306 	default:
307 		dev_err(dev, "rcar driver trip error\n");
308 		return -EINVAL;
309 	}
310 
311 	return 0;
312 }
313 
314 static int rcar_thermal_get_trip_temp(struct thermal_zone_device *zone,
315 				      int trip, int *temp)
316 {
317 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
318 	struct device *dev = rcar_priv_to_dev(priv);
319 
320 	/* see rcar_thermal_get_temp() */
321 	switch (trip) {
322 	case 0: /* +90 <= temp */
323 		*temp = MCELSIUS(90);
324 		break;
325 	default:
326 		dev_err(dev, "rcar driver trip error\n");
327 		return -EINVAL;
328 	}
329 
330 	return 0;
331 }
332 
333 static int rcar_thermal_notify(struct thermal_zone_device *zone,
334 			       int trip, enum thermal_trip_type type)
335 {
336 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
337 	struct device *dev = rcar_priv_to_dev(priv);
338 
339 	switch (type) {
340 	case THERMAL_TRIP_CRITICAL:
341 		/* FIXME */
342 		dev_warn(dev, "Thermal reached to critical temperature\n");
343 		break;
344 	default:
345 		break;
346 	}
347 
348 	return 0;
349 }
350 
351 static const struct thermal_zone_of_device_ops rcar_thermal_zone_of_ops = {
352 	.get_temp	= rcar_thermal_of_get_temp,
353 };
354 
355 static struct thermal_zone_device_ops rcar_thermal_zone_ops = {
356 	.get_temp	= rcar_thermal_get_temp,
357 	.get_trip_type	= rcar_thermal_get_trip_type,
358 	.get_trip_temp	= rcar_thermal_get_trip_temp,
359 	.notify		= rcar_thermal_notify,
360 };
361 
362 /*
363  *		interrupt
364  */
365 #define rcar_thermal_irq_enable(p)	_rcar_thermal_irq_ctrl(p, 1)
366 #define rcar_thermal_irq_disable(p)	_rcar_thermal_irq_ctrl(p, 0)
367 static void _rcar_thermal_irq_ctrl(struct rcar_thermal_priv *priv, int enable)
368 {
369 	struct rcar_thermal_common *common = priv->common;
370 	unsigned long flags;
371 	u32 mask = 0x3 << rcar_id_to_shift(priv); /* enable Rising/Falling */
372 
373 	if (!rcar_has_irq_support(priv))
374 		return;
375 
376 	spin_lock_irqsave(&common->lock, flags);
377 
378 	rcar_thermal_common_bset(common, INTMSK, mask, enable ? 0 : mask);
379 
380 	spin_unlock_irqrestore(&common->lock, flags);
381 }
382 
383 static void rcar_thermal_work(struct work_struct *work)
384 {
385 	struct rcar_thermal_priv *priv;
386 	int cctemp, nctemp;
387 	int ret;
388 
389 	priv = container_of(work, struct rcar_thermal_priv, work.work);
390 
391 	ret = rcar_thermal_get_current_temp(priv, &cctemp);
392 	if (ret < 0)
393 		return;
394 
395 	ret = rcar_thermal_update_temp(priv);
396 	if (ret < 0)
397 		return;
398 
399 	rcar_thermal_irq_enable(priv);
400 
401 	ret = rcar_thermal_get_current_temp(priv, &nctemp);
402 	if (ret < 0)
403 		return;
404 
405 	if (nctemp != cctemp)
406 		thermal_zone_device_update(priv->zone,
407 					   THERMAL_EVENT_UNSPECIFIED);
408 }
409 
410 static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
411 {
412 	struct device *dev = rcar_priv_to_dev(priv);
413 
414 	status = (status >> rcar_id_to_shift(priv)) & 0x3;
415 
416 	if (status) {
417 		dev_dbg(dev, "thermal%d %s%s\n",
418 			priv->id,
419 			(status & 0x2) ? "Rising " : "",
420 			(status & 0x1) ? "Falling" : "");
421 	}
422 
423 	return status;
424 }
425 
426 static irqreturn_t rcar_thermal_irq(int irq, void *data)
427 {
428 	struct rcar_thermal_common *common = data;
429 	struct rcar_thermal_priv *priv;
430 	unsigned long flags;
431 	u32 status, mask;
432 
433 	spin_lock_irqsave(&common->lock, flags);
434 
435 	mask	= rcar_thermal_common_read(common, INTMSK);
436 	status	= rcar_thermal_common_read(common, STR);
437 	rcar_thermal_common_write(common, STR, 0x000F0F0F & mask);
438 
439 	spin_unlock_irqrestore(&common->lock, flags);
440 
441 	status = status & ~mask;
442 
443 	/*
444 	 * check the status
445 	 */
446 	rcar_thermal_for_each_priv(priv, common) {
447 		if (rcar_thermal_had_changed(priv, status)) {
448 			rcar_thermal_irq_disable(priv);
449 			schedule_delayed_work(&priv->work,
450 					      msecs_to_jiffies(300));
451 		}
452 	}
453 
454 	return IRQ_HANDLED;
455 }
456 
457 /*
458  *		platform functions
459  */
460 static int rcar_thermal_remove(struct platform_device *pdev)
461 {
462 	struct rcar_thermal_common *common = platform_get_drvdata(pdev);
463 	struct device *dev = &pdev->dev;
464 	struct rcar_thermal_priv *priv;
465 
466 	rcar_thermal_for_each_priv(priv, common) {
467 		rcar_thermal_irq_disable(priv);
468 		if (priv->chip->use_of_thermal)
469 			thermal_remove_hwmon_sysfs(priv->zone);
470 		else
471 			thermal_zone_device_unregister(priv->zone);
472 	}
473 
474 	pm_runtime_put(dev);
475 	pm_runtime_disable(dev);
476 
477 	return 0;
478 }
479 
480 static int rcar_thermal_probe(struct platform_device *pdev)
481 {
482 	struct rcar_thermal_common *common;
483 	struct rcar_thermal_priv *priv;
484 	struct device *dev = &pdev->dev;
485 	struct resource *res, *irq;
486 	const struct rcar_thermal_chip *chip = of_device_get_match_data(dev);
487 	int mres = 0;
488 	int i;
489 	int ret = -ENODEV;
490 	int idle = IDLE_INTERVAL;
491 	u32 enr_bits = 0;
492 
493 	common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
494 	if (!common)
495 		return -ENOMEM;
496 
497 	platform_set_drvdata(pdev, common);
498 
499 	INIT_LIST_HEAD(&common->head);
500 	spin_lock_init(&common->lock);
501 	common->dev = dev;
502 
503 	pm_runtime_enable(dev);
504 	pm_runtime_get_sync(dev);
505 
506 	for (i = 0; i < chip->nirqs; i++) {
507 		irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
508 		if (!irq)
509 			continue;
510 		if (!common->base) {
511 			/*
512 			 * platform has IRQ support.
513 			 * Then, driver uses common registers
514 			 * rcar_has_irq_support() will be enabled
515 			 */
516 			res = platform_get_resource(pdev, IORESOURCE_MEM,
517 						    mres++);
518 			common->base = devm_ioremap_resource(dev, res);
519 			if (IS_ERR(common->base))
520 				return PTR_ERR(common->base);
521 
522 			idle = 0; /* polling delay is not needed */
523 		}
524 
525 		ret = devm_request_irq(dev, irq->start, rcar_thermal_irq,
526 				       IRQF_SHARED, dev_name(dev), common);
527 		if (ret) {
528 			dev_err(dev, "irq request failed\n ");
529 			goto error_unregister;
530 		}
531 
532 		/* update ENR bits */
533 		if (chip->irq_per_ch)
534 			enr_bits |= 1 << i;
535 	}
536 
537 	for (i = 0;; i++) {
538 		res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
539 		if (!res)
540 			break;
541 
542 		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
543 		if (!priv) {
544 			ret = -ENOMEM;
545 			goto error_unregister;
546 		}
547 
548 		priv->base = devm_ioremap_resource(dev, res);
549 		if (IS_ERR(priv->base)) {
550 			ret = PTR_ERR(priv->base);
551 			goto error_unregister;
552 		}
553 
554 		priv->common = common;
555 		priv->id = i;
556 		priv->chip = chip;
557 		mutex_init(&priv->lock);
558 		INIT_LIST_HEAD(&priv->list);
559 		INIT_DELAYED_WORK(&priv->work, rcar_thermal_work);
560 		ret = rcar_thermal_update_temp(priv);
561 		if (ret < 0)
562 			goto error_unregister;
563 
564 		if (chip->use_of_thermal)
565 			priv->zone = devm_thermal_zone_of_sensor_register(
566 						dev, i, priv,
567 						&rcar_thermal_zone_of_ops);
568 		else
569 			priv->zone = thermal_zone_device_register(
570 						"rcar_thermal",
571 						1, 0, priv,
572 						&rcar_thermal_zone_ops, NULL, 0,
573 						idle);
574 		if (IS_ERR(priv->zone)) {
575 			dev_err(dev, "can't register thermal zone\n");
576 			ret = PTR_ERR(priv->zone);
577 			priv->zone = NULL;
578 			goto error_unregister;
579 		}
580 
581 		if (chip->use_of_thermal) {
582 			/*
583 			 * thermal_zone doesn't enable hwmon as default,
584 			 * but, enable it here to keep compatible
585 			 */
586 			priv->zone->tzp->no_hwmon = false;
587 			ret = thermal_add_hwmon_sysfs(priv->zone);
588 			if (ret)
589 				goto error_unregister;
590 		}
591 
592 		rcar_thermal_irq_enable(priv);
593 
594 		list_move_tail(&priv->list, &common->head);
595 
596 		/* update ENR bits */
597 		if (!chip->irq_per_ch)
598 			enr_bits |= 3 << (i * 8);
599 	}
600 
601 	if (enr_bits)
602 		rcar_thermal_common_write(common, ENR, enr_bits);
603 
604 	dev_info(dev, "%d sensor probed\n", i);
605 
606 	return 0;
607 
608 error_unregister:
609 	rcar_thermal_remove(pdev);
610 
611 	return ret;
612 }
613 
614 #ifdef CONFIG_PM_SLEEP
615 static int rcar_thermal_suspend(struct device *dev)
616 {
617 	struct rcar_thermal_common *common = dev_get_drvdata(dev);
618 	struct rcar_thermal_priv *priv = list_first_entry(&common->head,
619 							  typeof(*priv), list);
620 
621 	if (priv->chip->needs_suspend_resume) {
622 		rcar_thermal_common_write(common, ENR, 0);
623 		rcar_thermal_irq_disable(priv);
624 		rcar_thermal_bset(priv, THSCR, CPCTL, 0);
625 	}
626 
627 	return 0;
628 }
629 
630 static int rcar_thermal_resume(struct device *dev)
631 {
632 	struct rcar_thermal_common *common = dev_get_drvdata(dev);
633 	struct rcar_thermal_priv *priv = list_first_entry(&common->head,
634 							  typeof(*priv), list);
635 	int ret;
636 
637 	if (priv->chip->needs_suspend_resume) {
638 		ret = rcar_thermal_update_temp(priv);
639 		if (ret < 0)
640 			return ret;
641 		rcar_thermal_irq_enable(priv);
642 		rcar_thermal_common_write(common, ENR, 0x03);
643 	}
644 
645 	return 0;
646 }
647 #endif
648 
649 static SIMPLE_DEV_PM_OPS(rcar_thermal_pm_ops, rcar_thermal_suspend,
650 			 rcar_thermal_resume);
651 
652 static struct platform_driver rcar_thermal_driver = {
653 	.driver	= {
654 		.name	= "rcar_thermal",
655 		.pm = &rcar_thermal_pm_ops,
656 		.of_match_table = rcar_thermal_dt_ids,
657 	},
658 	.probe		= rcar_thermal_probe,
659 	.remove		= rcar_thermal_remove,
660 };
661 module_platform_driver(rcar_thermal_driver);
662 
663 MODULE_LICENSE("GPL");
664 MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver");
665 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
666