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/platform_device.h>
27 #include <linux/pm_runtime.h>
28 #include <linux/reboot.h>
29 #include <linux/slab.h>
30 #include <linux/spinlock.h>
31 #include <linux/thermal.h>
32 
33 #define IDLE_INTERVAL	5000
34 
35 #define COMMON_STR	0x00
36 #define COMMON_ENR	0x04
37 #define COMMON_INTMSK	0x0c
38 
39 #define REG_POSNEG	0x20
40 #define REG_FILONOFF	0x28
41 #define REG_THSCR	0x2c
42 #define REG_THSSR	0x30
43 #define REG_INTCTRL	0x34
44 
45 /* THSCR */
46 #define CPCTL	(1 << 12)
47 
48 /* THSSR */
49 #define CTEMP	0x3f
50 
51 struct rcar_thermal_common {
52 	void __iomem *base;
53 	struct device *dev;
54 	struct list_head head;
55 	spinlock_t lock;
56 };
57 
58 struct rcar_thermal_priv {
59 	void __iomem *base;
60 	struct rcar_thermal_common *common;
61 	struct thermal_zone_device *zone;
62 	struct delayed_work work;
63 	struct mutex lock;
64 	struct list_head list;
65 	int id;
66 	int ctemp;
67 };
68 
69 #define rcar_thermal_for_each_priv(pos, common)	\
70 	list_for_each_entry(pos, &common->head, list)
71 
72 #define MCELSIUS(temp)			((temp) * 1000)
73 #define rcar_zone_to_priv(zone)		((zone)->devdata)
74 #define rcar_priv_to_dev(priv)		((priv)->common->dev)
75 #define rcar_has_irq_support(priv)	((priv)->common->base)
76 #define rcar_id_to_shift(priv)		((priv)->id * 8)
77 
78 #ifdef DEBUG
79 # define rcar_force_update_temp(priv)	1
80 #else
81 # define rcar_force_update_temp(priv)	0
82 #endif
83 
84 /*
85  *		basic functions
86  */
87 #define rcar_thermal_common_read(c, r) \
88 	_rcar_thermal_common_read(c, COMMON_ ##r)
89 static u32 _rcar_thermal_common_read(struct rcar_thermal_common *common,
90 				     u32 reg)
91 {
92 	return ioread32(common->base + reg);
93 }
94 
95 #define rcar_thermal_common_write(c, r, d) \
96 	_rcar_thermal_common_write(c, COMMON_ ##r, d)
97 static void _rcar_thermal_common_write(struct rcar_thermal_common *common,
98 				       u32 reg, u32 data)
99 {
100 	iowrite32(data, common->base + reg);
101 }
102 
103 #define rcar_thermal_common_bset(c, r, m, d) \
104 	_rcar_thermal_common_bset(c, COMMON_ ##r, m, d)
105 static void _rcar_thermal_common_bset(struct rcar_thermal_common *common,
106 				      u32 reg, u32 mask, u32 data)
107 {
108 	u32 val;
109 
110 	val = ioread32(common->base + reg);
111 	val &= ~mask;
112 	val |= (data & mask);
113 	iowrite32(val, common->base + reg);
114 }
115 
116 #define rcar_thermal_read(p, r) _rcar_thermal_read(p, REG_ ##r)
117 static u32 _rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg)
118 {
119 	return ioread32(priv->base + reg);
120 }
121 
122 #define rcar_thermal_write(p, r, d) _rcar_thermal_write(p, REG_ ##r, d)
123 static void _rcar_thermal_write(struct rcar_thermal_priv *priv,
124 				u32 reg, u32 data)
125 {
126 	iowrite32(data, priv->base + reg);
127 }
128 
129 #define rcar_thermal_bset(p, r, m, d) _rcar_thermal_bset(p, REG_ ##r, m, d)
130 static void _rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg,
131 			       u32 mask, u32 data)
132 {
133 	u32 val;
134 
135 	val = ioread32(priv->base + reg);
136 	val &= ~mask;
137 	val |= (data & mask);
138 	iowrite32(val, priv->base + reg);
139 }
140 
141 /*
142  *		zone device functions
143  */
144 static int rcar_thermal_update_temp(struct rcar_thermal_priv *priv)
145 {
146 	struct device *dev = rcar_priv_to_dev(priv);
147 	int i;
148 	int ctemp, old, new;
149 	int ret = -EINVAL;
150 
151 	mutex_lock(&priv->lock);
152 
153 	/*
154 	 * TSC decides a value of CPTAP automatically,
155 	 * and this is the conditions which validate interrupt.
156 	 */
157 	rcar_thermal_bset(priv, THSCR, CPCTL, CPCTL);
158 
159 	ctemp = 0;
160 	old = ~0;
161 	for (i = 0; i < 128; i++) {
162 		/*
163 		 * we need to wait 300us after changing comparator offset
164 		 * to get stable temperature.
165 		 * see "Usage Notes" on datasheet
166 		 */
167 		udelay(300);
168 
169 		new = rcar_thermal_read(priv, THSSR) & CTEMP;
170 		if (new == old) {
171 			ctemp = new;
172 			break;
173 		}
174 		old = new;
175 	}
176 
177 	if (!ctemp) {
178 		dev_err(dev, "thermal sensor was broken\n");
179 		goto err_out_unlock;
180 	}
181 
182 	/*
183 	 * enable IRQ
184 	 */
185 	if (rcar_has_irq_support(priv)) {
186 		rcar_thermal_write(priv, FILONOFF, 0);
187 
188 		/* enable Rising/Falling edge interrupt */
189 		rcar_thermal_write(priv, POSNEG,  0x1);
190 		rcar_thermal_write(priv, INTCTRL, (((ctemp - 0) << 8) |
191 						   ((ctemp - 1) << 0)));
192 	}
193 
194 	dev_dbg(dev, "thermal%d  %d -> %d\n", priv->id, priv->ctemp, ctemp);
195 
196 	priv->ctemp = ctemp;
197 	ret = 0;
198 err_out_unlock:
199 	mutex_unlock(&priv->lock);
200 	return ret;
201 }
202 
203 static int rcar_thermal_get_temp(struct thermal_zone_device *zone,
204 				 unsigned long *temp)
205 {
206 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
207 
208 	if (!rcar_has_irq_support(priv) || rcar_force_update_temp(priv))
209 		rcar_thermal_update_temp(priv);
210 
211 	mutex_lock(&priv->lock);
212 	*temp =  MCELSIUS((priv->ctemp * 5) - 65);
213 	mutex_unlock(&priv->lock);
214 
215 	return 0;
216 }
217 
218 static int rcar_thermal_get_trip_type(struct thermal_zone_device *zone,
219 				      int trip, enum thermal_trip_type *type)
220 {
221 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
222 	struct device *dev = rcar_priv_to_dev(priv);
223 
224 	/* see rcar_thermal_get_temp() */
225 	switch (trip) {
226 	case 0: /* +90 <= temp */
227 		*type = THERMAL_TRIP_CRITICAL;
228 		break;
229 	default:
230 		dev_err(dev, "rcar driver trip error\n");
231 		return -EINVAL;
232 	}
233 
234 	return 0;
235 }
236 
237 static int rcar_thermal_get_trip_temp(struct thermal_zone_device *zone,
238 				      int trip, unsigned long *temp)
239 {
240 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
241 	struct device *dev = rcar_priv_to_dev(priv);
242 
243 	/* see rcar_thermal_get_temp() */
244 	switch (trip) {
245 	case 0: /* +90 <= temp */
246 		*temp = MCELSIUS(90);
247 		break;
248 	default:
249 		dev_err(dev, "rcar driver trip error\n");
250 		return -EINVAL;
251 	}
252 
253 	return 0;
254 }
255 
256 static int rcar_thermal_notify(struct thermal_zone_device *zone,
257 			       int trip, enum thermal_trip_type type)
258 {
259 	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
260 	struct device *dev = rcar_priv_to_dev(priv);
261 
262 	switch (type) {
263 	case THERMAL_TRIP_CRITICAL:
264 		/* FIXME */
265 		dev_warn(dev, "Thermal reached to critical temperature\n");
266 		break;
267 	default:
268 		break;
269 	}
270 
271 	return 0;
272 }
273 
274 static struct thermal_zone_device_ops rcar_thermal_zone_ops = {
275 	.get_temp	= rcar_thermal_get_temp,
276 	.get_trip_type	= rcar_thermal_get_trip_type,
277 	.get_trip_temp	= rcar_thermal_get_trip_temp,
278 	.notify		= rcar_thermal_notify,
279 };
280 
281 /*
282  *		interrupt
283  */
284 #define rcar_thermal_irq_enable(p)	_rcar_thermal_irq_ctrl(p, 1)
285 #define rcar_thermal_irq_disable(p)	_rcar_thermal_irq_ctrl(p, 0)
286 static void _rcar_thermal_irq_ctrl(struct rcar_thermal_priv *priv, int enable)
287 {
288 	struct rcar_thermal_common *common = priv->common;
289 	unsigned long flags;
290 	u32 mask = 0x3 << rcar_id_to_shift(priv); /* enable Rising/Falling */
291 
292 	spin_lock_irqsave(&common->lock, flags);
293 
294 	rcar_thermal_common_bset(common, INTMSK, mask, enable ? 0 : mask);
295 
296 	spin_unlock_irqrestore(&common->lock, flags);
297 }
298 
299 static void rcar_thermal_work(struct work_struct *work)
300 {
301 	struct rcar_thermal_priv *priv;
302 
303 	priv = container_of(work, struct rcar_thermal_priv, work.work);
304 
305 	rcar_thermal_update_temp(priv);
306 	rcar_thermal_irq_enable(priv);
307 	thermal_zone_device_update(priv->zone);
308 }
309 
310 static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
311 {
312 	struct device *dev = rcar_priv_to_dev(priv);
313 
314 	status = (status >> rcar_id_to_shift(priv)) & 0x3;
315 
316 	if (status & 0x3) {
317 		dev_dbg(dev, "thermal%d %s%s\n",
318 			priv->id,
319 			(status & 0x2) ? "Rising " : "",
320 			(status & 0x1) ? "Falling" : "");
321 	}
322 
323 	return status;
324 }
325 
326 static irqreturn_t rcar_thermal_irq(int irq, void *data)
327 {
328 	struct rcar_thermal_common *common = data;
329 	struct rcar_thermal_priv *priv;
330 	unsigned long flags;
331 	u32 status, mask;
332 
333 	spin_lock_irqsave(&common->lock, flags);
334 
335 	mask	= rcar_thermal_common_read(common, INTMSK);
336 	status	= rcar_thermal_common_read(common, STR);
337 	rcar_thermal_common_write(common, STR, 0x000F0F0F & mask);
338 
339 	spin_unlock_irqrestore(&common->lock, flags);
340 
341 	status = status & ~mask;
342 
343 	/*
344 	 * check the status
345 	 */
346 	rcar_thermal_for_each_priv(priv, common) {
347 		if (rcar_thermal_had_changed(priv, status)) {
348 			rcar_thermal_irq_disable(priv);
349 			schedule_delayed_work(&priv->work,
350 					      msecs_to_jiffies(300));
351 		}
352 	}
353 
354 	return IRQ_HANDLED;
355 }
356 
357 /*
358  *		platform functions
359  */
360 static int rcar_thermal_probe(struct platform_device *pdev)
361 {
362 	struct rcar_thermal_common *common;
363 	struct rcar_thermal_priv *priv;
364 	struct device *dev = &pdev->dev;
365 	struct resource *res, *irq;
366 	int mres = 0;
367 	int i;
368 	int ret = -ENODEV;
369 	int idle = IDLE_INTERVAL;
370 
371 	common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
372 	if (!common) {
373 		dev_err(dev, "Could not allocate common\n");
374 		return -ENOMEM;
375 	}
376 
377 	INIT_LIST_HEAD(&common->head);
378 	spin_lock_init(&common->lock);
379 	common->dev = dev;
380 
381 	pm_runtime_enable(dev);
382 	pm_runtime_get_sync(dev);
383 
384 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
385 	if (irq) {
386 		int ret;
387 
388 		/*
389 		 * platform has IRQ support.
390 		 * Then, drier use common register
391 		 */
392 
393 		ret = devm_request_irq(dev, irq->start, rcar_thermal_irq, 0,
394 				       dev_name(dev), common);
395 		if (ret) {
396 			dev_err(dev, "irq request failed\n ");
397 			return ret;
398 		}
399 
400 		/*
401 		 * rcar_has_irq_support() will be enabled
402 		 */
403 		res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
404 		common->base = devm_ioremap_resource(dev, res);
405 		if (IS_ERR(common->base))
406 			return PTR_ERR(common->base);
407 
408 		/* enable temperature comparation */
409 		rcar_thermal_common_write(common, ENR, 0x00030303);
410 
411 		idle = 0; /* polling delaye is not needed */
412 	}
413 
414 	for (i = 0;; i++) {
415 		res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
416 		if (!res)
417 			break;
418 
419 		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
420 		if (!priv) {
421 			dev_err(dev, "Could not allocate priv\n");
422 			ret = -ENOMEM;
423 			goto error_unregister;
424 		}
425 
426 		priv->base = devm_ioremap_resource(dev, res);
427 		if (IS_ERR(priv->base)) {
428 			ret = PTR_ERR(priv->base);
429 			goto error_unregister;
430 		}
431 
432 		priv->common = common;
433 		priv->id = i;
434 		mutex_init(&priv->lock);
435 		INIT_LIST_HEAD(&priv->list);
436 		INIT_DELAYED_WORK(&priv->work, rcar_thermal_work);
437 		rcar_thermal_update_temp(priv);
438 
439 		priv->zone = thermal_zone_device_register("rcar_thermal",
440 						1, 0, priv,
441 						&rcar_thermal_zone_ops, NULL, 0,
442 						idle);
443 		if (IS_ERR(priv->zone)) {
444 			dev_err(dev, "can't register thermal zone\n");
445 			ret = PTR_ERR(priv->zone);
446 			goto error_unregister;
447 		}
448 
449 		if (rcar_has_irq_support(priv))
450 			rcar_thermal_irq_enable(priv);
451 
452 		list_move_tail(&priv->list, &common->head);
453 	}
454 
455 	platform_set_drvdata(pdev, common);
456 
457 	dev_info(dev, "%d sensor probed\n", i);
458 
459 	return 0;
460 
461 error_unregister:
462 	rcar_thermal_for_each_priv(priv, common) {
463 		thermal_zone_device_unregister(priv->zone);
464 		if (rcar_has_irq_support(priv))
465 			rcar_thermal_irq_disable(priv);
466 	}
467 
468 	pm_runtime_put_sync(dev);
469 	pm_runtime_disable(dev);
470 
471 	return ret;
472 }
473 
474 static int rcar_thermal_remove(struct platform_device *pdev)
475 {
476 	struct rcar_thermal_common *common = platform_get_drvdata(pdev);
477 	struct device *dev = &pdev->dev;
478 	struct rcar_thermal_priv *priv;
479 
480 	rcar_thermal_for_each_priv(priv, common) {
481 		thermal_zone_device_unregister(priv->zone);
482 		if (rcar_has_irq_support(priv))
483 			rcar_thermal_irq_disable(priv);
484 	}
485 
486 	pm_runtime_put_sync(dev);
487 	pm_runtime_disable(dev);
488 
489 	return 0;
490 }
491 
492 static const struct of_device_id rcar_thermal_dt_ids[] = {
493 	{ .compatible = "renesas,rcar-thermal", },
494 	{},
495 };
496 MODULE_DEVICE_TABLE(of, rcar_thermal_dt_ids);
497 
498 static struct platform_driver rcar_thermal_driver = {
499 	.driver	= {
500 		.name	= "rcar_thermal",
501 		.of_match_table = rcar_thermal_dt_ids,
502 	},
503 	.probe		= rcar_thermal_probe,
504 	.remove		= rcar_thermal_remove,
505 };
506 module_platform_driver(rcar_thermal_driver);
507 
508 MODULE_LICENSE("GPL");
509 MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver");
510 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
511