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_priv {
62 	void __iomem *base;
63 	struct rcar_thermal_common *common;
64 	struct thermal_zone_device *zone;
65 	struct delayed_work work;
66 	struct mutex lock;
67 	struct list_head list;
68 	int id;
69 	u32 ctemp;
70 };
71 
72 #define rcar_thermal_for_each_priv(pos, common)	\
73 	list_for_each_entry(pos, &common->head, list)
74 
75 #define MCELSIUS(temp)			((temp) * 1000)
76 #define rcar_zone_to_priv(zone)		((zone)->devdata)
77 #define rcar_priv_to_dev(priv)		((priv)->common->dev)
78 #define rcar_has_irq_support(priv)	((priv)->common->base)
79 #define rcar_id_to_shift(priv)		((priv)->id * 8)
80 #define rcar_of_data(dev)		((unsigned long)of_device_get_match_data(dev))
81 #define rcar_use_of_thermal(dev)	(rcar_of_data(dev) == USE_OF_THERMAL)
82 
83 #define USE_OF_THERMAL	1
84 static const struct of_device_id rcar_thermal_dt_ids[] = {
85 	{ .compatible = "renesas,rcar-thermal", },
86 	{ .compatible = "renesas,rcar-gen2-thermal", .data = (void *)USE_OF_THERMAL },
87 	{},
88 };
89 MODULE_DEVICE_TABLE(of, rcar_thermal_dt_ids);
90 
91 /*
92  *		basic functions
93  */
94 #define rcar_thermal_common_read(c, r) \
95 	_rcar_thermal_common_read(c, COMMON_ ##r)
96 static u32 _rcar_thermal_common_read(struct rcar_thermal_common *common,
97 				     u32 reg)
98 {
99 	return ioread32(common->base + reg);
100 }
101 
102 #define rcar_thermal_common_write(c, r, d) \
103 	_rcar_thermal_common_write(c, COMMON_ ##r, d)
104 static void _rcar_thermal_common_write(struct rcar_thermal_common *common,
105 				       u32 reg, u32 data)
106 {
107 	iowrite32(data, common->base + reg);
108 }
109 
110 #define rcar_thermal_common_bset(c, r, m, d) \
111 	_rcar_thermal_common_bset(c, COMMON_ ##r, m, d)
112 static void _rcar_thermal_common_bset(struct rcar_thermal_common *common,
113 				      u32 reg, u32 mask, u32 data)
114 {
115 	u32 val;
116 
117 	val = ioread32(common->base + reg);
118 	val &= ~mask;
119 	val |= (data & mask);
120 	iowrite32(val, common->base + reg);
121 }
122 
123 #define rcar_thermal_read(p, r) _rcar_thermal_read(p, REG_ ##r)
124 static u32 _rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg)
125 {
126 	return ioread32(priv->base + reg);
127 }
128 
129 #define rcar_thermal_write(p, r, d) _rcar_thermal_write(p, REG_ ##r, d)
130 static void _rcar_thermal_write(struct rcar_thermal_priv *priv,
131 				u32 reg, u32 data)
132 {
133 	iowrite32(data, priv->base + reg);
134 }
135 
136 #define rcar_thermal_bset(p, r, m, d) _rcar_thermal_bset(p, REG_ ##r, m, d)
137 static void _rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg,
138 			       u32 mask, u32 data)
139 {
140 	u32 val;
141 
142 	val = ioread32(priv->base + reg);
143 	val &= ~mask;
144 	val |= (data & mask);
145 	iowrite32(val, priv->base + reg);
146 }
147 
148 /*
149  *		zone device functions
150  */
151 static int rcar_thermal_update_temp(struct rcar_thermal_priv *priv)
152 {
153 	struct device *dev = rcar_priv_to_dev(priv);
154 	int i;
155 	u32 ctemp, old, new;
156 	int ret = -EINVAL;
157 
158 	mutex_lock(&priv->lock);
159 
160 	/*
161 	 * TSC decides a value of CPTAP automatically,
162 	 * and this is the conditions which validate interrupt.
163 	 */
164 	rcar_thermal_bset(priv, THSCR, CPCTL, CPCTL);
165 
166 	ctemp = 0;
167 	old = ~0;
168 	for (i = 0; i < 128; i++) {
169 		/*
170 		 * we need to wait 300us after changing comparator offset
171 		 * to get stable temperature.
172 		 * see "Usage Notes" on datasheet
173 		 */
174 		udelay(300);
175 
176 		new = rcar_thermal_read(priv, THSSR) & CTEMP;
177 		if (new == old) {
178 			ctemp = new;
179 			break;
180 		}
181 		old = new;
182 	}
183 
184 	if (!ctemp) {
185 		dev_err(dev, "thermal sensor was broken\n");
186 		goto err_out_unlock;
187 	}
188 
189 	/*
190 	 * enable IRQ
191 	 */
192 	if (rcar_has_irq_support(priv)) {
193 		rcar_thermal_write(priv, FILONOFF, 0);
194 
195 		/* enable Rising/Falling edge interrupt */
196 		rcar_thermal_write(priv, POSNEG,  0x1);
197 		rcar_thermal_write(priv, INTCTRL, (((ctemp - 0) << 8) |
198 						   ((ctemp - 1) << 0)));
199 	}
200 
201 	dev_dbg(dev, "thermal%d  %d -> %d\n", priv->id, priv->ctemp, ctemp);
202 
203 	priv->ctemp = ctemp;
204 	ret = 0;
205 err_out_unlock:
206 	mutex_unlock(&priv->lock);
207 	return ret;
208 }
209 
210 static int rcar_thermal_get_current_temp(struct rcar_thermal_priv *priv,
211 					 int *temp)
212 {
213 	int tmp;
214 	int ret;
215 
216 	ret = rcar_thermal_update_temp(priv);
217 	if (ret < 0)
218 		return ret;
219 
220 	mutex_lock(&priv->lock);
221 	tmp =  MCELSIUS((priv->ctemp * 5) - 65);
222 	mutex_unlock(&priv->lock);
223 
224 	if ((tmp < MCELSIUS(-45)) || (tmp > MCELSIUS(125))) {
225 		struct device *dev = rcar_priv_to_dev(priv);
226 
227 		dev_err(dev, "it couldn't measure temperature correctly\n");
228 		return -EIO;
229 	}
230 
231 	*temp = tmp;
232 
233 	return 0;
234 }
235 
236 static int rcar_thermal_of_get_temp(void *data, int *temp)
237 {
238 	struct rcar_thermal_priv *priv = data;
239 
240 	return rcar_thermal_get_current_temp(priv, temp);
241 }
242 
243 static int rcar_thermal_get_temp(struct thermal_zone_device *zone, int *temp)
244 {
245 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
246 
247 	return rcar_thermal_get_current_temp(priv, temp);
248 }
249 
250 static int rcar_thermal_get_trip_type(struct thermal_zone_device *zone,
251 				      int trip, enum thermal_trip_type *type)
252 {
253 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
254 	struct device *dev = rcar_priv_to_dev(priv);
255 
256 	/* see rcar_thermal_get_temp() */
257 	switch (trip) {
258 	case 0: /* +90 <= temp */
259 		*type = THERMAL_TRIP_CRITICAL;
260 		break;
261 	default:
262 		dev_err(dev, "rcar driver trip error\n");
263 		return -EINVAL;
264 	}
265 
266 	return 0;
267 }
268 
269 static int rcar_thermal_get_trip_temp(struct thermal_zone_device *zone,
270 				      int trip, int *temp)
271 {
272 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
273 	struct device *dev = rcar_priv_to_dev(priv);
274 
275 	/* see rcar_thermal_get_temp() */
276 	switch (trip) {
277 	case 0: /* +90 <= temp */
278 		*temp = MCELSIUS(90);
279 		break;
280 	default:
281 		dev_err(dev, "rcar driver trip error\n");
282 		return -EINVAL;
283 	}
284 
285 	return 0;
286 }
287 
288 static int rcar_thermal_notify(struct thermal_zone_device *zone,
289 			       int trip, enum thermal_trip_type type)
290 {
291 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
292 	struct device *dev = rcar_priv_to_dev(priv);
293 
294 	switch (type) {
295 	case THERMAL_TRIP_CRITICAL:
296 		/* FIXME */
297 		dev_warn(dev, "Thermal reached to critical temperature\n");
298 		break;
299 	default:
300 		break;
301 	}
302 
303 	return 0;
304 }
305 
306 static const struct thermal_zone_of_device_ops rcar_thermal_zone_of_ops = {
307 	.get_temp	= rcar_thermal_of_get_temp,
308 };
309 
310 static struct thermal_zone_device_ops rcar_thermal_zone_ops = {
311 	.get_temp	= rcar_thermal_get_temp,
312 	.get_trip_type	= rcar_thermal_get_trip_type,
313 	.get_trip_temp	= rcar_thermal_get_trip_temp,
314 	.notify		= rcar_thermal_notify,
315 };
316 
317 /*
318  *		interrupt
319  */
320 #define rcar_thermal_irq_enable(p)	_rcar_thermal_irq_ctrl(p, 1)
321 #define rcar_thermal_irq_disable(p)	_rcar_thermal_irq_ctrl(p, 0)
322 static void _rcar_thermal_irq_ctrl(struct rcar_thermal_priv *priv, int enable)
323 {
324 	struct rcar_thermal_common *common = priv->common;
325 	unsigned long flags;
326 	u32 mask = 0x3 << rcar_id_to_shift(priv); /* enable Rising/Falling */
327 
328 	if (!rcar_has_irq_support(priv))
329 		return;
330 
331 	spin_lock_irqsave(&common->lock, flags);
332 
333 	rcar_thermal_common_bset(common, INTMSK, mask, enable ? 0 : mask);
334 
335 	spin_unlock_irqrestore(&common->lock, flags);
336 }
337 
338 static void rcar_thermal_work(struct work_struct *work)
339 {
340 	struct rcar_thermal_priv *priv;
341 	int cctemp, nctemp;
342 	int ret;
343 
344 	priv = container_of(work, struct rcar_thermal_priv, work.work);
345 
346 	ret = rcar_thermal_get_current_temp(priv, &cctemp);
347 	if (ret < 0)
348 		return;
349 
350 	ret = rcar_thermal_update_temp(priv);
351 	if (ret < 0)
352 		return;
353 
354 	rcar_thermal_irq_enable(priv);
355 
356 	ret = rcar_thermal_get_current_temp(priv, &nctemp);
357 	if (ret < 0)
358 		return;
359 
360 	if (nctemp != cctemp)
361 		thermal_zone_device_update(priv->zone,
362 					   THERMAL_EVENT_UNSPECIFIED);
363 }
364 
365 static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
366 {
367 	struct device *dev = rcar_priv_to_dev(priv);
368 
369 	status = (status >> rcar_id_to_shift(priv)) & 0x3;
370 
371 	if (status) {
372 		dev_dbg(dev, "thermal%d %s%s\n",
373 			priv->id,
374 			(status & 0x2) ? "Rising " : "",
375 			(status & 0x1) ? "Falling" : "");
376 	}
377 
378 	return status;
379 }
380 
381 static irqreturn_t rcar_thermal_irq(int irq, void *data)
382 {
383 	struct rcar_thermal_common *common = data;
384 	struct rcar_thermal_priv *priv;
385 	unsigned long flags;
386 	u32 status, mask;
387 
388 	spin_lock_irqsave(&common->lock, flags);
389 
390 	mask	= rcar_thermal_common_read(common, INTMSK);
391 	status	= rcar_thermal_common_read(common, STR);
392 	rcar_thermal_common_write(common, STR, 0x000F0F0F & mask);
393 
394 	spin_unlock_irqrestore(&common->lock, flags);
395 
396 	status = status & ~mask;
397 
398 	/*
399 	 * check the status
400 	 */
401 	rcar_thermal_for_each_priv(priv, common) {
402 		if (rcar_thermal_had_changed(priv, status)) {
403 			rcar_thermal_irq_disable(priv);
404 			schedule_delayed_work(&priv->work,
405 					      msecs_to_jiffies(300));
406 		}
407 	}
408 
409 	return IRQ_HANDLED;
410 }
411 
412 /*
413  *		platform functions
414  */
415 static int rcar_thermal_remove(struct platform_device *pdev)
416 {
417 	struct rcar_thermal_common *common = platform_get_drvdata(pdev);
418 	struct device *dev = &pdev->dev;
419 	struct rcar_thermal_priv *priv;
420 
421 	rcar_thermal_for_each_priv(priv, common) {
422 		rcar_thermal_irq_disable(priv);
423 		if (rcar_use_of_thermal(dev))
424 			thermal_remove_hwmon_sysfs(priv->zone);
425 		else
426 			thermal_zone_device_unregister(priv->zone);
427 	}
428 
429 	pm_runtime_put(dev);
430 	pm_runtime_disable(dev);
431 
432 	return 0;
433 }
434 
435 static int rcar_thermal_probe(struct platform_device *pdev)
436 {
437 	struct rcar_thermal_common *common;
438 	struct rcar_thermal_priv *priv;
439 	struct device *dev = &pdev->dev;
440 	struct resource *res, *irq;
441 	int mres = 0;
442 	int i;
443 	int ret = -ENODEV;
444 	int idle = IDLE_INTERVAL;
445 	u32 enr_bits = 0;
446 
447 	common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
448 	if (!common)
449 		return -ENOMEM;
450 
451 	platform_set_drvdata(pdev, common);
452 
453 	INIT_LIST_HEAD(&common->head);
454 	spin_lock_init(&common->lock);
455 	common->dev = dev;
456 
457 	pm_runtime_enable(dev);
458 	pm_runtime_get_sync(dev);
459 
460 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
461 	if (irq) {
462 		/*
463 		 * platform has IRQ support.
464 		 * Then, driver uses common registers
465 		 * rcar_has_irq_support() will be enabled
466 		 */
467 		res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
468 		common->base = devm_ioremap_resource(dev, res);
469 		if (IS_ERR(common->base))
470 			return PTR_ERR(common->base);
471 
472 		idle = 0; /* polling delay is not needed */
473 	}
474 
475 	for (i = 0;; i++) {
476 		res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
477 		if (!res)
478 			break;
479 
480 		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
481 		if (!priv) {
482 			ret = -ENOMEM;
483 			goto error_unregister;
484 		}
485 
486 		priv->base = devm_ioremap_resource(dev, res);
487 		if (IS_ERR(priv->base)) {
488 			ret = PTR_ERR(priv->base);
489 			goto error_unregister;
490 		}
491 
492 		priv->common = common;
493 		priv->id = i;
494 		mutex_init(&priv->lock);
495 		INIT_LIST_HEAD(&priv->list);
496 		INIT_DELAYED_WORK(&priv->work, rcar_thermal_work);
497 		ret = rcar_thermal_update_temp(priv);
498 		if (ret < 0)
499 			goto error_unregister;
500 
501 		if (rcar_use_of_thermal(dev))
502 			priv->zone = devm_thermal_zone_of_sensor_register(
503 						dev, i, priv,
504 						&rcar_thermal_zone_of_ops);
505 		else
506 			priv->zone = thermal_zone_device_register(
507 						"rcar_thermal",
508 						1, 0, priv,
509 						&rcar_thermal_zone_ops, NULL, 0,
510 						idle);
511 		if (IS_ERR(priv->zone)) {
512 			dev_err(dev, "can't register thermal zone\n");
513 			ret = PTR_ERR(priv->zone);
514 			priv->zone = NULL;
515 			goto error_unregister;
516 		}
517 
518 		if (rcar_use_of_thermal(dev)) {
519 			/*
520 			 * thermal_zone doesn't enable hwmon as default,
521 			 * but, enable it here to keep compatible
522 			 */
523 			priv->zone->tzp->no_hwmon = false;
524 			ret = thermal_add_hwmon_sysfs(priv->zone);
525 			if (ret)
526 				goto error_unregister;
527 		}
528 
529 		rcar_thermal_irq_enable(priv);
530 
531 		list_move_tail(&priv->list, &common->head);
532 
533 		/* update ENR bits */
534 		enr_bits |= 3 << (i * 8);
535 	}
536 
537 	/* enable temperature comparation */
538 	if (irq) {
539 		ret = devm_request_irq(dev, irq->start, rcar_thermal_irq, 0,
540 				       dev_name(dev), common);
541 		if (ret) {
542 			dev_err(dev, "irq request failed\n ");
543 			goto error_unregister;
544 		}
545 
546 		rcar_thermal_common_write(common, ENR, enr_bits);
547 	}
548 
549 	dev_info(dev, "%d sensor probed\n", i);
550 
551 	return 0;
552 
553 error_unregister:
554 	rcar_thermal_remove(pdev);
555 
556 	return ret;
557 }
558 
559 static struct platform_driver rcar_thermal_driver = {
560 	.driver	= {
561 		.name	= "rcar_thermal",
562 		.of_match_table = rcar_thermal_dt_ids,
563 	},
564 	.probe		= rcar_thermal_probe,
565 	.remove		= rcar_thermal_remove,
566 };
567 module_platform_driver(rcar_thermal_driver);
568 
569 MODULE_LICENSE("GPL");
570 MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver");
571 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
572