1 /*
2  * exynos4_tmu.c - Samsung EXYNOS4 TMU (Thermal Management Unit)
3  *
4  *  Copyright (C) 2011 Samsung Electronics
5  *  Donggeun Kim <dg77.kim@samsung.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; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  *
21  */
22 
23 #include <linux/module.h>
24 #include <linux/err.h>
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
27 #include <linux/platform_device.h>
28 #include <linux/interrupt.h>
29 #include <linux/clk.h>
30 #include <linux/workqueue.h>
31 #include <linux/sysfs.h>
32 #include <linux/kobject.h>
33 #include <linux/io.h>
34 #include <linux/mutex.h>
35 
36 #include <linux/hwmon.h>
37 #include <linux/hwmon-sysfs.h>
38 
39 #include <linux/platform_data/exynos4_tmu.h>
40 
41 #define EXYNOS4_TMU_REG_TRIMINFO	0x0
42 #define EXYNOS4_TMU_REG_CONTROL		0x20
43 #define EXYNOS4_TMU_REG_STATUS		0x28
44 #define EXYNOS4_TMU_REG_CURRENT_TEMP	0x40
45 #define EXYNOS4_TMU_REG_THRESHOLD_TEMP	0x44
46 #define EXYNOS4_TMU_REG_TRIG_LEVEL0	0x50
47 #define EXYNOS4_TMU_REG_TRIG_LEVEL1	0x54
48 #define EXYNOS4_TMU_REG_TRIG_LEVEL2	0x58
49 #define EXYNOS4_TMU_REG_TRIG_LEVEL3	0x5C
50 #define EXYNOS4_TMU_REG_PAST_TEMP0	0x60
51 #define EXYNOS4_TMU_REG_PAST_TEMP1	0x64
52 #define EXYNOS4_TMU_REG_PAST_TEMP2	0x68
53 #define EXYNOS4_TMU_REG_PAST_TEMP3	0x6C
54 #define EXYNOS4_TMU_REG_INTEN		0x70
55 #define EXYNOS4_TMU_REG_INTSTAT		0x74
56 #define EXYNOS4_TMU_REG_INTCLEAR	0x78
57 
58 #define EXYNOS4_TMU_GAIN_SHIFT		8
59 #define EXYNOS4_TMU_REF_VOLTAGE_SHIFT	24
60 
61 #define EXYNOS4_TMU_TRIM_TEMP_MASK	0xff
62 #define EXYNOS4_TMU_CORE_ON	3
63 #define EXYNOS4_TMU_CORE_OFF	2
64 #define EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET	50
65 #define EXYNOS4_TMU_TRIG_LEVEL0_MASK	0x1
66 #define EXYNOS4_TMU_TRIG_LEVEL1_MASK	0x10
67 #define EXYNOS4_TMU_TRIG_LEVEL2_MASK	0x100
68 #define EXYNOS4_TMU_TRIG_LEVEL3_MASK	0x1000
69 #define EXYNOS4_TMU_INTCLEAR_VAL	0x1111
70 
71 struct exynos4_tmu_data {
72 	struct exynos4_tmu_platform_data *pdata;
73 	struct device *hwmon_dev;
74 	struct resource *mem;
75 	void __iomem *base;
76 	int irq;
77 	struct work_struct irq_work;
78 	struct mutex lock;
79 	struct clk *clk;
80 	u8 temp_error1, temp_error2;
81 };
82 
83 /*
84  * TMU treats temperature as a mapped temperature code.
85  * The temperature is converted differently depending on the calibration type.
86  */
temp_to_code(struct exynos4_tmu_data * data,u8 temp)87 static int temp_to_code(struct exynos4_tmu_data *data, u8 temp)
88 {
89 	struct exynos4_tmu_platform_data *pdata = data->pdata;
90 	int temp_code;
91 
92 	/* temp should range between 25 and 125 */
93 	if (temp < 25 || temp > 125) {
94 		temp_code = -EINVAL;
95 		goto out;
96 	}
97 
98 	switch (pdata->cal_type) {
99 	case TYPE_TWO_POINT_TRIMMING:
100 		temp_code = (temp - 25) *
101 		    (data->temp_error2 - data->temp_error1) /
102 		    (85 - 25) + data->temp_error1;
103 		break;
104 	case TYPE_ONE_POINT_TRIMMING:
105 		temp_code = temp + data->temp_error1 - 25;
106 		break;
107 	default:
108 		temp_code = temp + EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
109 		break;
110 	}
111 out:
112 	return temp_code;
113 }
114 
115 /*
116  * Calculate a temperature value from a temperature code.
117  * The unit of the temperature is degree Celsius.
118  */
code_to_temp(struct exynos4_tmu_data * data,u8 temp_code)119 static int code_to_temp(struct exynos4_tmu_data *data, u8 temp_code)
120 {
121 	struct exynos4_tmu_platform_data *pdata = data->pdata;
122 	int temp;
123 
124 	/* temp_code should range between 75 and 175 */
125 	if (temp_code < 75 || temp_code > 175) {
126 		temp = -ENODATA;
127 		goto out;
128 	}
129 
130 	switch (pdata->cal_type) {
131 	case TYPE_TWO_POINT_TRIMMING:
132 		temp = (temp_code - data->temp_error1) * (85 - 25) /
133 		    (data->temp_error2 - data->temp_error1) + 25;
134 		break;
135 	case TYPE_ONE_POINT_TRIMMING:
136 		temp = temp_code - data->temp_error1 + 25;
137 		break;
138 	default:
139 		temp = temp_code - EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
140 		break;
141 	}
142 out:
143 	return temp;
144 }
145 
exynos4_tmu_initialize(struct platform_device * pdev)146 static int exynos4_tmu_initialize(struct platform_device *pdev)
147 {
148 	struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
149 	struct exynos4_tmu_platform_data *pdata = data->pdata;
150 	unsigned int status, trim_info;
151 	int ret = 0, threshold_code;
152 
153 	mutex_lock(&data->lock);
154 	clk_enable(data->clk);
155 
156 	status = readb(data->base + EXYNOS4_TMU_REG_STATUS);
157 	if (!status) {
158 		ret = -EBUSY;
159 		goto out;
160 	}
161 
162 	/* Save trimming info in order to perform calibration */
163 	trim_info = readl(data->base + EXYNOS4_TMU_REG_TRIMINFO);
164 	data->temp_error1 = trim_info & EXYNOS4_TMU_TRIM_TEMP_MASK;
165 	data->temp_error2 = ((trim_info >> 8) & EXYNOS4_TMU_TRIM_TEMP_MASK);
166 
167 	/* Write temperature code for threshold */
168 	threshold_code = temp_to_code(data, pdata->threshold);
169 	if (threshold_code < 0) {
170 		ret = threshold_code;
171 		goto out;
172 	}
173 	writeb(threshold_code,
174 		data->base + EXYNOS4_TMU_REG_THRESHOLD_TEMP);
175 
176 	writeb(pdata->trigger_levels[0],
177 		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL0);
178 	writeb(pdata->trigger_levels[1],
179 		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL1);
180 	writeb(pdata->trigger_levels[2],
181 		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL2);
182 	writeb(pdata->trigger_levels[3],
183 		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL3);
184 
185 	writel(EXYNOS4_TMU_INTCLEAR_VAL,
186 		data->base + EXYNOS4_TMU_REG_INTCLEAR);
187 out:
188 	clk_disable(data->clk);
189 	mutex_unlock(&data->lock);
190 
191 	return ret;
192 }
193 
exynos4_tmu_control(struct platform_device * pdev,bool on)194 static void exynos4_tmu_control(struct platform_device *pdev, bool on)
195 {
196 	struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
197 	struct exynos4_tmu_platform_data *pdata = data->pdata;
198 	unsigned int con, interrupt_en;
199 
200 	mutex_lock(&data->lock);
201 	clk_enable(data->clk);
202 
203 	con = pdata->reference_voltage << EXYNOS4_TMU_REF_VOLTAGE_SHIFT |
204 		pdata->gain << EXYNOS4_TMU_GAIN_SHIFT;
205 	if (on) {
206 		con |= EXYNOS4_TMU_CORE_ON;
207 		interrupt_en = pdata->trigger_level3_en << 12 |
208 			pdata->trigger_level2_en << 8 |
209 			pdata->trigger_level1_en << 4 |
210 			pdata->trigger_level0_en;
211 	} else {
212 		con |= EXYNOS4_TMU_CORE_OFF;
213 		interrupt_en = 0; /* Disable all interrupts */
214 	}
215 	writel(interrupt_en, data->base + EXYNOS4_TMU_REG_INTEN);
216 	writel(con, data->base + EXYNOS4_TMU_REG_CONTROL);
217 
218 	clk_disable(data->clk);
219 	mutex_unlock(&data->lock);
220 }
221 
exynos4_tmu_read(struct exynos4_tmu_data * data)222 static int exynos4_tmu_read(struct exynos4_tmu_data *data)
223 {
224 	u8 temp_code;
225 	int temp;
226 
227 	mutex_lock(&data->lock);
228 	clk_enable(data->clk);
229 
230 	temp_code = readb(data->base + EXYNOS4_TMU_REG_CURRENT_TEMP);
231 	temp = code_to_temp(data, temp_code);
232 
233 	clk_disable(data->clk);
234 	mutex_unlock(&data->lock);
235 
236 	return temp;
237 }
238 
exynos4_tmu_work(struct work_struct * work)239 static void exynos4_tmu_work(struct work_struct *work)
240 {
241 	struct exynos4_tmu_data *data = container_of(work,
242 			struct exynos4_tmu_data, irq_work);
243 
244 	mutex_lock(&data->lock);
245 	clk_enable(data->clk);
246 
247 	writel(EXYNOS4_TMU_INTCLEAR_VAL, data->base + EXYNOS4_TMU_REG_INTCLEAR);
248 
249 	kobject_uevent(&data->hwmon_dev->kobj, KOBJ_CHANGE);
250 
251 	enable_irq(data->irq);
252 
253 	clk_disable(data->clk);
254 	mutex_unlock(&data->lock);
255 }
256 
exynos4_tmu_irq(int irq,void * id)257 static irqreturn_t exynos4_tmu_irq(int irq, void *id)
258 {
259 	struct exynos4_tmu_data *data = id;
260 
261 	disable_irq_nosync(irq);
262 	schedule_work(&data->irq_work);
263 
264 	return IRQ_HANDLED;
265 }
266 
exynos4_tmu_show_name(struct device * dev,struct device_attribute * attr,char * buf)267 static ssize_t exynos4_tmu_show_name(struct device *dev,
268 		struct device_attribute *attr, char *buf)
269 {
270 	return sprintf(buf, "exynos4-tmu\n");
271 }
272 
exynos4_tmu_show_temp(struct device * dev,struct device_attribute * attr,char * buf)273 static ssize_t exynos4_tmu_show_temp(struct device *dev,
274 		struct device_attribute *attr, char *buf)
275 {
276 	struct exynos4_tmu_data *data = dev_get_drvdata(dev);
277 	int ret;
278 
279 	ret = exynos4_tmu_read(data);
280 	if (ret < 0)
281 		return ret;
282 
283 	/* convert from degree Celsius to millidegree Celsius */
284 	return sprintf(buf, "%d\n", ret * 1000);
285 }
286 
exynos4_tmu_show_alarm(struct device * dev,struct device_attribute * devattr,char * buf)287 static ssize_t exynos4_tmu_show_alarm(struct device *dev,
288 		struct device_attribute *devattr, char *buf)
289 {
290 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
291 	struct exynos4_tmu_data *data = dev_get_drvdata(dev);
292 	struct exynos4_tmu_platform_data *pdata = data->pdata;
293 	int temp;
294 	unsigned int trigger_level;
295 
296 	temp = exynos4_tmu_read(data);
297 	if (temp < 0)
298 		return temp;
299 
300 	trigger_level = pdata->threshold + pdata->trigger_levels[attr->index];
301 
302 	return sprintf(buf, "%d\n", !!(temp > trigger_level));
303 }
304 
exynos4_tmu_show_level(struct device * dev,struct device_attribute * devattr,char * buf)305 static ssize_t exynos4_tmu_show_level(struct device *dev,
306 		struct device_attribute *devattr, char *buf)
307 {
308 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
309 	struct exynos4_tmu_data *data = dev_get_drvdata(dev);
310 	struct exynos4_tmu_platform_data *pdata = data->pdata;
311 	unsigned int temp = pdata->threshold +
312 			pdata->trigger_levels[attr->index];
313 
314 	return sprintf(buf, "%u\n", temp * 1000);
315 }
316 
317 static DEVICE_ATTR(name, S_IRUGO, exynos4_tmu_show_name, NULL);
318 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, exynos4_tmu_show_temp, NULL, 0);
319 
320 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO,
321 		exynos4_tmu_show_alarm, NULL, 1);
322 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO,
323 		exynos4_tmu_show_alarm, NULL, 2);
324 static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO,
325 		exynos4_tmu_show_alarm, NULL, 3);
326 
327 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, exynos4_tmu_show_level, NULL, 1);
328 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, exynos4_tmu_show_level, NULL, 2);
329 static SENSOR_DEVICE_ATTR(temp1_emergency, S_IRUGO,
330 		exynos4_tmu_show_level, NULL, 3);
331 
332 static struct attribute *exynos4_tmu_attributes[] = {
333 	&dev_attr_name.attr,
334 	&sensor_dev_attr_temp1_input.dev_attr.attr,
335 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
336 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
337 	&sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
338 	&sensor_dev_attr_temp1_max.dev_attr.attr,
339 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
340 	&sensor_dev_attr_temp1_emergency.dev_attr.attr,
341 	NULL,
342 };
343 
344 static const struct attribute_group exynos4_tmu_attr_group = {
345 	.attrs = exynos4_tmu_attributes,
346 };
347 
exynos4_tmu_probe(struct platform_device * pdev)348 static int __devinit exynos4_tmu_probe(struct platform_device *pdev)
349 {
350 	struct exynos4_tmu_data *data;
351 	struct exynos4_tmu_platform_data *pdata = pdev->dev.platform_data;
352 	int ret;
353 
354 	if (!pdata) {
355 		dev_err(&pdev->dev, "No platform init data supplied.\n");
356 		return -ENODEV;
357 	}
358 
359 	data = kzalloc(sizeof(struct exynos4_tmu_data), GFP_KERNEL);
360 	if (!data) {
361 		dev_err(&pdev->dev, "Failed to allocate driver structure\n");
362 		return -ENOMEM;
363 	}
364 
365 	data->irq = platform_get_irq(pdev, 0);
366 	if (data->irq < 0) {
367 		ret = data->irq;
368 		dev_err(&pdev->dev, "Failed to get platform irq\n");
369 		goto err_free;
370 	}
371 
372 	INIT_WORK(&data->irq_work, exynos4_tmu_work);
373 
374 	data->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
375 	if (!data->mem) {
376 		ret = -ENOENT;
377 		dev_err(&pdev->dev, "Failed to get platform resource\n");
378 		goto err_free;
379 	}
380 
381 	data->mem = request_mem_region(data->mem->start,
382 			resource_size(data->mem), pdev->name);
383 	if (!data->mem) {
384 		ret = -ENODEV;
385 		dev_err(&pdev->dev, "Failed to request memory region\n");
386 		goto err_free;
387 	}
388 
389 	data->base = ioremap(data->mem->start, resource_size(data->mem));
390 	if (!data->base) {
391 		ret = -ENODEV;
392 		dev_err(&pdev->dev, "Failed to ioremap memory\n");
393 		goto err_mem_region;
394 	}
395 
396 	ret = request_irq(data->irq, exynos4_tmu_irq,
397 		IRQF_TRIGGER_RISING,
398 		"exynos4-tmu", data);
399 	if (ret) {
400 		dev_err(&pdev->dev, "Failed to request irq: %d\n", data->irq);
401 		goto err_io_remap;
402 	}
403 
404 	data->clk = clk_get(NULL, "tmu_apbif");
405 	if (IS_ERR(data->clk)) {
406 		ret = PTR_ERR(data->clk);
407 		dev_err(&pdev->dev, "Failed to get clock\n");
408 		goto err_irq;
409 	}
410 
411 	data->pdata = pdata;
412 	platform_set_drvdata(pdev, data);
413 	mutex_init(&data->lock);
414 
415 	ret = exynos4_tmu_initialize(pdev);
416 	if (ret) {
417 		dev_err(&pdev->dev, "Failed to initialize TMU\n");
418 		goto err_clk;
419 	}
420 
421 	ret = sysfs_create_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
422 	if (ret) {
423 		dev_err(&pdev->dev, "Failed to create sysfs group\n");
424 		goto err_clk;
425 	}
426 
427 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
428 	if (IS_ERR(data->hwmon_dev)) {
429 		ret = PTR_ERR(data->hwmon_dev);
430 		dev_err(&pdev->dev, "Failed to register hwmon device\n");
431 		goto err_create_group;
432 	}
433 
434 	exynos4_tmu_control(pdev, true);
435 
436 	return 0;
437 
438 err_create_group:
439 	sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
440 err_clk:
441 	platform_set_drvdata(pdev, NULL);
442 	clk_put(data->clk);
443 err_irq:
444 	free_irq(data->irq, data);
445 err_io_remap:
446 	iounmap(data->base);
447 err_mem_region:
448 	release_mem_region(data->mem->start, resource_size(data->mem));
449 err_free:
450 	kfree(data);
451 
452 	return ret;
453 }
454 
exynos4_tmu_remove(struct platform_device * pdev)455 static int __devexit exynos4_tmu_remove(struct platform_device *pdev)
456 {
457 	struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
458 
459 	exynos4_tmu_control(pdev, false);
460 
461 	hwmon_device_unregister(data->hwmon_dev);
462 	sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
463 
464 	clk_put(data->clk);
465 
466 	free_irq(data->irq, data);
467 
468 	iounmap(data->base);
469 	release_mem_region(data->mem->start, resource_size(data->mem));
470 
471 	platform_set_drvdata(pdev, NULL);
472 
473 	kfree(data);
474 
475 	return 0;
476 }
477 
478 #ifdef CONFIG_PM
exynos4_tmu_suspend(struct platform_device * pdev,pm_message_t state)479 static int exynos4_tmu_suspend(struct platform_device *pdev, pm_message_t state)
480 {
481 	exynos4_tmu_control(pdev, false);
482 
483 	return 0;
484 }
485 
exynos4_tmu_resume(struct platform_device * pdev)486 static int exynos4_tmu_resume(struct platform_device *pdev)
487 {
488 	exynos4_tmu_initialize(pdev);
489 	exynos4_tmu_control(pdev, true);
490 
491 	return 0;
492 }
493 #else
494 #define exynos4_tmu_suspend NULL
495 #define exynos4_tmu_resume NULL
496 #endif
497 
498 static struct platform_driver exynos4_tmu_driver = {
499 	.driver = {
500 		.name   = "exynos4-tmu",
501 		.owner  = THIS_MODULE,
502 	},
503 	.probe = exynos4_tmu_probe,
504 	.remove	= __devexit_p(exynos4_tmu_remove),
505 	.suspend = exynos4_tmu_suspend,
506 	.resume = exynos4_tmu_resume,
507 };
508 
509 module_platform_driver(exynos4_tmu_driver);
510 
511 MODULE_DESCRIPTION("EXYNOS4 TMU Driver");
512 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
513 MODULE_LICENSE("GPL");
514 MODULE_ALIAS("platform:exynos4-tmu");
515