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 #define IDLE_INTERVAL	5000
35 
36 #define COMMON_STR	0x00
37 #define COMMON_ENR	0x04
38 #define COMMON_INTMSK	0x0c
39 
40 #define REG_POSNEG	0x20
41 #define REG_FILONOFF	0x28
42 #define REG_THSCR	0x2c
43 #define REG_THSSR	0x30
44 #define REG_INTCTRL	0x34
45 
46 /* THSCR */
47 #define CPCTL	(1 << 12)
48 
49 /* THSSR */
50 #define CTEMP	0x3f
51 
52 struct rcar_thermal_common {
53 	void __iomem *base;
54 	struct device *dev;
55 	struct list_head head;
56 	spinlock_t lock;
57 };
58 
59 struct rcar_thermal_priv {
60 	void __iomem *base;
61 	struct rcar_thermal_common *common;
62 	struct thermal_zone_device *zone;
63 	struct delayed_work work;
64 	struct mutex lock;
65 	struct list_head list;
66 	int id;
67 	u32 ctemp;
68 };
69 
70 #define rcar_thermal_for_each_priv(pos, common)	\
71 	list_for_each_entry(pos, &common->head, list)
72 
73 #define MCELSIUS(temp)			((temp) * 1000)
74 #define rcar_zone_to_priv(zone)		((zone)->devdata)
75 #define rcar_priv_to_dev(priv)		((priv)->common->dev)
76 #define rcar_has_irq_support(priv)	((priv)->common->base)
77 #define rcar_id_to_shift(priv)		((priv)->id * 8)
78 
79 #define USE_OF_THERMAL	1
80 static const struct of_device_id rcar_thermal_dt_ids[] = {
81 	{ .compatible = "renesas,rcar-thermal", },
82 	{ .compatible = "renesas,rcar-gen2-thermal", .data = (void *)USE_OF_THERMAL },
83 	{},
84 };
85 MODULE_DEVICE_TABLE(of, rcar_thermal_dt_ids);
86 
87 /*
88  *		basic functions
89  */
90 #define rcar_thermal_common_read(c, r) \
91 	_rcar_thermal_common_read(c, COMMON_ ##r)
92 static u32 _rcar_thermal_common_read(struct rcar_thermal_common *common,
93 				     u32 reg)
94 {
95 	return ioread32(common->base + reg);
96 }
97 
98 #define rcar_thermal_common_write(c, r, d) \
99 	_rcar_thermal_common_write(c, COMMON_ ##r, d)
100 static void _rcar_thermal_common_write(struct rcar_thermal_common *common,
101 				       u32 reg, u32 data)
102 {
103 	iowrite32(data, common->base + reg);
104 }
105 
106 #define rcar_thermal_common_bset(c, r, m, d) \
107 	_rcar_thermal_common_bset(c, COMMON_ ##r, m, d)
108 static void _rcar_thermal_common_bset(struct rcar_thermal_common *common,
109 				      u32 reg, u32 mask, u32 data)
110 {
111 	u32 val;
112 
113 	val = ioread32(common->base + reg);
114 	val &= ~mask;
115 	val |= (data & mask);
116 	iowrite32(val, common->base + reg);
117 }
118 
119 #define rcar_thermal_read(p, r) _rcar_thermal_read(p, REG_ ##r)
120 static u32 _rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg)
121 {
122 	return ioread32(priv->base + reg);
123 }
124 
125 #define rcar_thermal_write(p, r, d) _rcar_thermal_write(p, REG_ ##r, d)
126 static void _rcar_thermal_write(struct rcar_thermal_priv *priv,
127 				u32 reg, u32 data)
128 {
129 	iowrite32(data, priv->base + reg);
130 }
131 
132 #define rcar_thermal_bset(p, r, m, d) _rcar_thermal_bset(p, REG_ ##r, m, d)
133 static void _rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg,
134 			       u32 mask, u32 data)
135 {
136 	u32 val;
137 
138 	val = ioread32(priv->base + reg);
139 	val &= ~mask;
140 	val |= (data & mask);
141 	iowrite32(val, priv->base + reg);
142 }
143 
144 /*
145  *		zone device functions
146  */
147 static int rcar_thermal_update_temp(struct rcar_thermal_priv *priv)
148 {
149 	struct device *dev = rcar_priv_to_dev(priv);
150 	int i;
151 	u32 ctemp, old, new;
152 	int ret = -EINVAL;
153 
154 	mutex_lock(&priv->lock);
155 
156 	/*
157 	 * TSC decides a value of CPTAP automatically,
158 	 * and this is the conditions which validate interrupt.
159 	 */
160 	rcar_thermal_bset(priv, THSCR, CPCTL, CPCTL);
161 
162 	ctemp = 0;
163 	old = ~0;
164 	for (i = 0; i < 128; i++) {
165 		/*
166 		 * we need to wait 300us after changing comparator offset
167 		 * to get stable temperature.
168 		 * see "Usage Notes" on datasheet
169 		 */
170 		udelay(300);
171 
172 		new = rcar_thermal_read(priv, THSSR) & CTEMP;
173 		if (new == old) {
174 			ctemp = new;
175 			break;
176 		}
177 		old = new;
178 	}
179 
180 	if (!ctemp) {
181 		dev_err(dev, "thermal sensor was broken\n");
182 		goto err_out_unlock;
183 	}
184 
185 	/*
186 	 * enable IRQ
187 	 */
188 	if (rcar_has_irq_support(priv)) {
189 		rcar_thermal_write(priv, FILONOFF, 0);
190 
191 		/* enable Rising/Falling edge interrupt */
192 		rcar_thermal_write(priv, POSNEG,  0x1);
193 		rcar_thermal_write(priv, INTCTRL, (((ctemp - 0) << 8) |
194 						   ((ctemp - 1) << 0)));
195 	}
196 
197 	dev_dbg(dev, "thermal%d  %d -> %d\n", priv->id, priv->ctemp, ctemp);
198 
199 	priv->ctemp = ctemp;
200 	ret = 0;
201 err_out_unlock:
202 	mutex_unlock(&priv->lock);
203 	return ret;
204 }
205 
206 static int rcar_thermal_get_current_temp(struct rcar_thermal_priv *priv,
207 					 int *temp)
208 {
209 	int tmp;
210 	int ret;
211 
212 	ret = rcar_thermal_update_temp(priv);
213 	if (ret < 0)
214 		return ret;
215 
216 	mutex_lock(&priv->lock);
217 	tmp =  MCELSIUS((priv->ctemp * 5) - 65);
218 	mutex_unlock(&priv->lock);
219 
220 	if ((tmp < MCELSIUS(-45)) || (tmp > MCELSIUS(125))) {
221 		struct device *dev = rcar_priv_to_dev(priv);
222 
223 		dev_err(dev, "it couldn't measure temperature correctly\n");
224 		return -EIO;
225 	}
226 
227 	*temp = tmp;
228 
229 	return 0;
230 }
231 
232 static int rcar_thermal_of_get_temp(void *data, int *temp)
233 {
234 	struct rcar_thermal_priv *priv = data;
235 
236 	return rcar_thermal_get_current_temp(priv, temp);
237 }
238 
239 static int rcar_thermal_get_temp(struct thermal_zone_device *zone, int *temp)
240 {
241 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
242 
243 	return rcar_thermal_get_current_temp(priv, temp);
244 }
245 
246 static int rcar_thermal_get_trip_type(struct thermal_zone_device *zone,
247 				      int trip, enum thermal_trip_type *type)
248 {
249 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
250 	struct device *dev = rcar_priv_to_dev(priv);
251 
252 	/* see rcar_thermal_get_temp() */
253 	switch (trip) {
254 	case 0: /* +90 <= temp */
255 		*type = THERMAL_TRIP_CRITICAL;
256 		break;
257 	default:
258 		dev_err(dev, "rcar driver trip error\n");
259 		return -EINVAL;
260 	}
261 
262 	return 0;
263 }
264 
265 static int rcar_thermal_get_trip_temp(struct thermal_zone_device *zone,
266 				      int trip, int *temp)
267 {
268 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
269 	struct device *dev = rcar_priv_to_dev(priv);
270 
271 	/* see rcar_thermal_get_temp() */
272 	switch (trip) {
273 	case 0: /* +90 <= temp */
274 		*temp = MCELSIUS(90);
275 		break;
276 	default:
277 		dev_err(dev, "rcar driver trip error\n");
278 		return -EINVAL;
279 	}
280 
281 	return 0;
282 }
283 
284 static int rcar_thermal_notify(struct thermal_zone_device *zone,
285 			       int trip, enum thermal_trip_type type)
286 {
287 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
288 	struct device *dev = rcar_priv_to_dev(priv);
289 
290 	switch (type) {
291 	case THERMAL_TRIP_CRITICAL:
292 		/* FIXME */
293 		dev_warn(dev, "Thermal reached to critical temperature\n");
294 		break;
295 	default:
296 		break;
297 	}
298 
299 	return 0;
300 }
301 
302 static const struct thermal_zone_of_device_ops rcar_thermal_zone_of_ops = {
303 	.get_temp	= rcar_thermal_of_get_temp,
304 };
305 
306 static struct thermal_zone_device_ops rcar_thermal_zone_ops = {
307 	.get_temp	= rcar_thermal_get_temp,
308 	.get_trip_type	= rcar_thermal_get_trip_type,
309 	.get_trip_temp	= rcar_thermal_get_trip_temp,
310 	.notify		= rcar_thermal_notify,
311 };
312 
313 /*
314  *		interrupt
315  */
316 #define rcar_thermal_irq_enable(p)	_rcar_thermal_irq_ctrl(p, 1)
317 #define rcar_thermal_irq_disable(p)	_rcar_thermal_irq_ctrl(p, 0)
318 static void _rcar_thermal_irq_ctrl(struct rcar_thermal_priv *priv, int enable)
319 {
320 	struct rcar_thermal_common *common = priv->common;
321 	unsigned long flags;
322 	u32 mask = 0x3 << rcar_id_to_shift(priv); /* enable Rising/Falling */
323 
324 	if (!rcar_has_irq_support(priv))
325 		return;
326 
327 	spin_lock_irqsave(&common->lock, flags);
328 
329 	rcar_thermal_common_bset(common, INTMSK, mask, enable ? 0 : mask);
330 
331 	spin_unlock_irqrestore(&common->lock, flags);
332 }
333 
334 static void rcar_thermal_work(struct work_struct *work)
335 {
336 	struct rcar_thermal_priv *priv;
337 	int cctemp, nctemp;
338 	int ret;
339 
340 	priv = container_of(work, struct rcar_thermal_priv, work.work);
341 
342 	ret = rcar_thermal_get_current_temp(priv, &cctemp);
343 	if (ret < 0)
344 		return;
345 
346 	ret = rcar_thermal_update_temp(priv);
347 	if (ret < 0)
348 		return;
349 
350 	rcar_thermal_irq_enable(priv);
351 
352 	ret = rcar_thermal_get_current_temp(priv, &nctemp);
353 	if (ret < 0)
354 		return;
355 
356 	if (nctemp != cctemp)
357 		thermal_zone_device_update(priv->zone);
358 }
359 
360 static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
361 {
362 	struct device *dev = rcar_priv_to_dev(priv);
363 
364 	status = (status >> rcar_id_to_shift(priv)) & 0x3;
365 
366 	if (status) {
367 		dev_dbg(dev, "thermal%d %s%s\n",
368 			priv->id,
369 			(status & 0x2) ? "Rising " : "",
370 			(status & 0x1) ? "Falling" : "");
371 	}
372 
373 	return status;
374 }
375 
376 static irqreturn_t rcar_thermal_irq(int irq, void *data)
377 {
378 	struct rcar_thermal_common *common = data;
379 	struct rcar_thermal_priv *priv;
380 	unsigned long flags;
381 	u32 status, mask;
382 
383 	spin_lock_irqsave(&common->lock, flags);
384 
385 	mask	= rcar_thermal_common_read(common, INTMSK);
386 	status	= rcar_thermal_common_read(common, STR);
387 	rcar_thermal_common_write(common, STR, 0x000F0F0F & mask);
388 
389 	spin_unlock_irqrestore(&common->lock, flags);
390 
391 	status = status & ~mask;
392 
393 	/*
394 	 * check the status
395 	 */
396 	rcar_thermal_for_each_priv(priv, common) {
397 		if (rcar_thermal_had_changed(priv, status)) {
398 			rcar_thermal_irq_disable(priv);
399 			schedule_delayed_work(&priv->work,
400 					      msecs_to_jiffies(300));
401 		}
402 	}
403 
404 	return IRQ_HANDLED;
405 }
406 
407 /*
408  *		platform functions
409  */
410 static int rcar_thermal_remove(struct platform_device *pdev)
411 {
412 	struct rcar_thermal_common *common = platform_get_drvdata(pdev);
413 	struct device *dev = &pdev->dev;
414 	struct rcar_thermal_priv *priv;
415 
416 	rcar_thermal_for_each_priv(priv, common) {
417 		rcar_thermal_irq_disable(priv);
418 		thermal_zone_device_unregister(priv->zone);
419 	}
420 
421 	pm_runtime_put(dev);
422 	pm_runtime_disable(dev);
423 
424 	return 0;
425 }
426 
427 static int rcar_thermal_probe(struct platform_device *pdev)
428 {
429 	struct rcar_thermal_common *common;
430 	struct rcar_thermal_priv *priv;
431 	struct device *dev = &pdev->dev;
432 	struct resource *res, *irq;
433 	unsigned long of_data = (unsigned long)of_device_get_match_data(dev);
434 	int mres = 0;
435 	int i;
436 	int ret = -ENODEV;
437 	int idle = IDLE_INTERVAL;
438 	u32 enr_bits = 0;
439 
440 	common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
441 	if (!common)
442 		return -ENOMEM;
443 
444 	platform_set_drvdata(pdev, common);
445 
446 	INIT_LIST_HEAD(&common->head);
447 	spin_lock_init(&common->lock);
448 	common->dev = dev;
449 
450 	pm_runtime_enable(dev);
451 	pm_runtime_get_sync(dev);
452 
453 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
454 	if (irq) {
455 		/*
456 		 * platform has IRQ support.
457 		 * Then, driver uses common registers
458 		 * rcar_has_irq_support() will be enabled
459 		 */
460 		res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
461 		common->base = devm_ioremap_resource(dev, res);
462 		if (IS_ERR(common->base))
463 			return PTR_ERR(common->base);
464 
465 		idle = 0; /* polling delay is not needed */
466 	}
467 
468 	for (i = 0;; i++) {
469 		res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
470 		if (!res)
471 			break;
472 
473 		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
474 		if (!priv) {
475 			ret = -ENOMEM;
476 			goto error_unregister;
477 		}
478 
479 		priv->base = devm_ioremap_resource(dev, res);
480 		if (IS_ERR(priv->base)) {
481 			ret = PTR_ERR(priv->base);
482 			goto error_unregister;
483 		}
484 
485 		priv->common = common;
486 		priv->id = i;
487 		mutex_init(&priv->lock);
488 		INIT_LIST_HEAD(&priv->list);
489 		INIT_DELAYED_WORK(&priv->work, rcar_thermal_work);
490 		ret = rcar_thermal_update_temp(priv);
491 		if (ret < 0)
492 			goto error_unregister;
493 
494 		if (of_data == USE_OF_THERMAL)
495 			priv->zone = devm_thermal_zone_of_sensor_register(
496 						dev, i, priv,
497 						&rcar_thermal_zone_of_ops);
498 		else
499 			priv->zone = thermal_zone_device_register(
500 						"rcar_thermal",
501 						1, 0, priv,
502 						&rcar_thermal_zone_ops, NULL, 0,
503 						idle);
504 		if (IS_ERR(priv->zone)) {
505 			dev_err(dev, "can't register thermal zone\n");
506 			ret = PTR_ERR(priv->zone);
507 			goto error_unregister;
508 		}
509 
510 		rcar_thermal_irq_enable(priv);
511 
512 		list_move_tail(&priv->list, &common->head);
513 
514 		/* update ENR bits */
515 		enr_bits |= 3 << (i * 8);
516 	}
517 
518 	/* enable temperature comparation */
519 	if (irq) {
520 		ret = devm_request_irq(dev, irq->start, rcar_thermal_irq, 0,
521 				       dev_name(dev), common);
522 		if (ret) {
523 			dev_err(dev, "irq request failed\n ");
524 			goto error_unregister;
525 		}
526 
527 		rcar_thermal_common_write(common, ENR, enr_bits);
528 	}
529 
530 	dev_info(dev, "%d sensor probed\n", i);
531 
532 	return 0;
533 
534 error_unregister:
535 	rcar_thermal_remove(pdev);
536 
537 	return ret;
538 }
539 
540 static struct platform_driver rcar_thermal_driver = {
541 	.driver	= {
542 		.name	= "rcar_thermal",
543 		.of_match_table = rcar_thermal_dt_ids,
544 	},
545 	.probe		= rcar_thermal_probe,
546 	.remove		= rcar_thermal_remove,
547 };
548 module_platform_driver(rcar_thermal_driver);
549 
550 MODULE_LICENSE("GPL");
551 MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver");
552 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
553