aboutsummaryrefslogtreecommitdiff
path: root/drivers/hwmon/exynos4_tmu.c
blob: e912059140cd492306b607a7a108931107bf9168 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
/*
 * exynos4_tmu.c - Samsung EXYNOS4 TMU (Thermal Management Unit)
 *
 *  Copyright (C) 2011 Samsung Electronics
 *  Donggeun Kim <dg77.kim@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/workqueue.h>
#include <linux/sysfs.h>
#include <linux/kobject.h>
#include <linux/io.h>
#include <linux/mutex.h>

#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>

#include <linux/platform_data/exynos4_tmu.h>

#define EXYNOS4_TMU_REG_TRIMINFO	0x0
#define EXYNOS4_TMU_REG_CONTROL		0x20
#define EXYNOS4_TMU_REG_STATUS		0x28
#define EXYNOS4_TMU_REG_CURRENT_TEMP	0x40
#define EXYNOS4_TMU_REG_THRESHOLD_TEMP	0x44
#define EXYNOS4_TMU_REG_TRIG_LEVEL0	0x50
#define EXYNOS4_TMU_REG_TRIG_LEVEL1	0x54
#define EXYNOS4_TMU_REG_TRIG_LEVEL2	0x58
#define EXYNOS4_TMU_REG_TRIG_LEVEL3	0x5C
#define EXYNOS4_TMU_REG_PAST_TEMP0	0x60
#define EXYNOS4_TMU_REG_PAST_TEMP1	0x64
#define EXYNOS4_TMU_REG_PAST_TEMP2	0x68
#define EXYNOS4_TMU_REG_PAST_TEMP3	0x6C
#define EXYNOS4_TMU_REG_INTEN		0x70
#define EXYNOS4_TMU_REG_INTSTAT		0x74
#define EXYNOS4_TMU_REG_INTCLEAR	0x78

#define EXYNOS4_TMU_GAIN_SHIFT		8
#define EXYNOS4_TMU_REF_VOLTAGE_SHIFT	24

#define EXYNOS4_TMU_TRIM_TEMP_MASK	0xff
#define EXYNOS4_TMU_CORE_ON	3
#define EXYNOS4_TMU_CORE_OFF	2
#define EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET	50
#define EXYNOS4_TMU_TRIG_LEVEL0_MASK	0x1
#define EXYNOS4_TMU_TRIG_LEVEL1_MASK	0x10
#define EXYNOS4_TMU_TRIG_LEVEL2_MASK	0x100
#define EXYNOS4_TMU_TRIG_LEVEL3_MASK	0x1000
#define EXYNOS4_TMU_INTCLEAR_VAL	0x1111

struct exynos4_tmu_data {
	struct exynos4_tmu_platform_data *pdata;
	struct device *hwmon_dev;
	struct resource *mem;
	void __iomem *base;
	int irq;
	struct work_struct irq_work;
	struct mutex lock;
	struct clk *clk;
	u8 temp_error1, temp_error2;
};

/*
 * TMU treats temperature as a mapped temperature code.
 * The temperature is converted differently depending on the calibration type.
 */
static int temp_to_code(struct exynos4_tmu_data *data, u8 temp)
{
	struct exynos4_tmu_platform_data *pdata = data->pdata;
	int temp_code;

	/* temp should range between 25 and 125 */
	if (temp < 25 || temp > 125) {
		temp_code = -EINVAL;
		goto out;
	}

	switch (pdata->cal_type) {
	case TYPE_TWO_POINT_TRIMMING:
		temp_code = (temp - 25) *
		    (data->temp_error2 - data->temp_error1) /
		    (85 - 25) + data->temp_error1;
		break;
	case TYPE_ONE_POINT_TRIMMING:
		temp_code = temp + data->temp_error1 - 25;
		break;
	default:
		temp_code = temp + EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
		break;
	}
out:
	return temp_code;
}

/*
 * Calculate a temperature value from a temperature code.
 * The unit of the temperature is degree Celsius.
 */
static int code_to_temp(struct exynos4_tmu_data *data, u8 temp_code)
{
	struct exynos4_tmu_platform_data *pdata = data->pdata;
	int temp;

	/* temp_code should range between 75 and 175 */
	if (temp_code < 75 || temp_code > 175) {
		temp = -ENODATA;
		goto out;
	}

	switch (pdata->cal_type) {
	case TYPE_TWO_POINT_TRIMMING:
		temp = (temp_code - data->temp_error1) * (85 - 25) /
		    (data->temp_error2 - data->temp_error1) + 25;
		break;
	case TYPE_ONE_POINT_TRIMMING:
		temp = temp_code - data->temp_error1 + 25;
		break;
	default:
		temp = temp_code - EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
		break;
	}
out:
	return temp;
}

static int exynos4_tmu_initialize(struct platform_device *pdev)
{
	struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
	struct exynos4_tmu_platform_data *pdata = data->pdata;
	unsigned int status, trim_info;
	int ret = 0, threshold_code;

	mutex_lock(&data->lock);
	clk_enable(data->clk);

	status = readb(data->base + EXYNOS4_TMU_REG_STATUS);
	if (!status) {
		ret = -EBUSY;
		goto out;
	}

	/* Save trimming info in order to perform calibration */
	trim_info = readl(data->base + EXYNOS4_TMU_REG_TRIMINFO);
	data->temp_error1 = trim_info & EXYNOS4_TMU_TRIM_TEMP_MASK;
	data->temp_error2 = ((trim_info >> 8) & EXYNOS4_TMU_TRIM_TEMP_MASK);

	/* Write temperature code for threshold */
	threshold_code = temp_to_code(data, pdata->threshold);
	if (threshold_code < 0) {
		ret = threshold_code;
		goto out;
	}
	writeb(threshold_code,
		data->base + EXYNOS4_TMU_REG_THRESHOLD_TEMP);

	writeb(pdata->trigger_levels[0],
		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL0);
	writeb(pdata->trigger_levels[1],
		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL1);
	writeb(pdata->trigger_levels[2],
		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL2);
	writeb(pdata->trigger_levels[3],
		data->base + EXYNOS4_TMU_REG_TRIG_LEVEL3);

	writel(EXYNOS4_TMU_INTCLEAR_VAL,
		data->base + EXYNOS4_TMU_REG_INTCLEAR);
out:
	clk_disable(data->clk);
	mutex_unlock(&data->lock);

	return ret;
}

static void exynos4_tmu_control(struct platform_device *pdev, bool on)
{
	struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
	struct exynos4_tmu_platform_data *pdata = data->pdata;
	unsigned int con, interrupt_en;

	mutex_lock(&data->lock);
	clk_enable(data->clk);

	con = pdata->reference_voltage << EXYNOS4_TMU_REF_VOLTAGE_SHIFT |
		pdata->gain << EXYNOS4_TMU_GAIN_SHIFT;
	if (on) {
		con |= EXYNOS4_TMU_CORE_ON;
		interrupt_en = pdata->trigger_level3_en << 12 |
			pdata->trigger_level2_en << 8 |
			pdata->trigger_level1_en << 4 |
			pdata->trigger_level0_en;
	} else {
		con |= EXYNOS4_TMU_CORE_OFF;
		interrupt_en = 0; /* Disable all interrupts */
	}
	writel(interrupt_en, data->base + EXYNOS4_TMU_REG_INTEN);
	writel(con, data->base + EXYNOS4_TMU_REG_CONTROL);

	clk_disable(data->clk);
	mutex_unlock(&data->lock);
}

static int exynos4_tmu_read(struct exynos4_tmu_data *data)
{
	u8 temp_code;
	int temp;

	mutex_lock(&data->lock);
	clk_enable(data->clk);

	temp_code = readb(data->base + EXYNOS4_TMU_REG_CURRENT_TEMP);
	temp = code_to_temp(data, temp_code);

	clk_disable(data->clk);
	mutex_unlock(&data->lock);

	return temp;
}

static void exynos4_tmu_work(struct work_struct *work)
{
	struct exynos4_tmu_data *data = container_of(work,
			struct exynos4_tmu_data, irq_work);

	mutex_lock(&data->lock);
	clk_enable(data->clk);

	writel(EXYNOS4_TMU_INTCLEAR_VAL, data->base + EXYNOS4_TMU_REG_INTCLEAR);

	kobject_uevent(&data->hwmon_dev->kobj, KOBJ_CHANGE);

	enable_irq(data->irq);

	clk_disable(data->clk);
	mutex_unlock(&data->lock);
}

static irqreturn_t exynos4_tmu_irq(int irq, void *id)
{
	struct exynos4_tmu_data *data = id;

	disable_irq_nosync(irq);
	schedule_work(&data->irq_work);

	return IRQ_HANDLED;
}

static ssize_t exynos4_tmu_show_name(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "exynos4-tmu\n");
}

static ssize_t exynos4_tmu_show_temp(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct exynos4_tmu_data *data = dev_get_drvdata(dev);
	int ret;

	ret = exynos4_tmu_read(data);
	if (ret < 0)
		return ret;

	/* convert from degree Celsius to millidegree Celsius */
	return sprintf(buf, "%d\n", ret * 1000);
}

static ssize_t exynos4_tmu_show_alarm(struct device *dev,
		struct device_attribute *devattr, char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct exynos4_tmu_data *data = dev_get_drvdata(dev);
	struct exynos4_tmu_platform_data *pdata = data->pdata;
	int temp;
	unsigned int trigger_level;

	temp = exynos4_tmu_read(data);
	if (temp < 0)
		return temp;

	trigger_level = pdata->threshold + pdata->trigger_levels[attr->index];

	return sprintf(buf, "%d\n", !!(temp > trigger_level));
}

static ssize_t exynos4_tmu_show_level(struct device *dev,
		struct device_attribute *devattr, char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct exynos4_tmu_data *data = dev_get_drvdata(dev);
	struct exynos4_tmu_platform_data *pdata = data->pdata;
	unsigned int temp = pdata->threshold +
			pdata->trigger_levels[attr->index];

	return sprintf(buf, "%u\n", temp * 1000);
}

static DEVICE_ATTR(name, S_IRUGO, exynos4_tmu_show_name, NULL);
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, exynos4_tmu_show_temp, NULL, 0);

static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO,
		exynos4_tmu_show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO,
		exynos4_tmu_show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO,
		exynos4_tmu_show_alarm, NULL, 3);

static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, exynos4_tmu_show_level, NULL, 1);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, exynos4_tmu_show_level, NULL, 2);
static SENSOR_DEVICE_ATTR(temp1_emergency, S_IRUGO,
		exynos4_tmu_show_level, NULL, 3);

static struct attribute *exynos4_tmu_attributes[] = {
	&dev_attr_name.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_crit.dev_attr.attr,
	&sensor_dev_attr_temp1_emergency.dev_attr.attr,
	NULL,
};

static const struct attribute_group exynos4_tmu_attr_group = {
	.attrs = exynos4_tmu_attributes,
};

static int __devinit exynos4_tmu_probe(struct platform_device *pdev)
{
	struct exynos4_tmu_data *data;
	struct exynos4_tmu_platform_data *pdata = pdev->dev.platform_data;
	int ret;

	if (!pdata) {
		dev_err(&pdev->dev, "No platform init data supplied.\n");
		return -ENODEV;
	}

	data = kzalloc(sizeof(struct exynos4_tmu_data), GFP_KERNEL);
	if (!data) {
		dev_err(&pdev->dev, "Failed to allocate driver structure\n");
		return -ENOMEM;
	}

	data->irq = platform_get_irq(pdev, 0);
	if (data->irq < 0) {
		ret = data->irq;
		dev_err(&pdev->dev, "Failed to get platform irq\n");
		goto err_free;
	}

	INIT_WORK(&data->irq_work, exynos4_tmu_work);

	data->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!data->mem) {
		ret = -ENOENT;
		dev_err(&pdev->dev, "Failed to get platform resource\n");
		goto err_free;
	}

	data->mem = request_mem_region(data->mem->start,
			resource_size(data->mem), pdev->name);
	if (!data->mem) {
		ret = -ENODEV;
		dev_err(&pdev->dev, "Failed to request memory region\n");
		goto err_free;
	}

	data->base = ioremap(data->mem->start, resource_size(data->mem));
	if (!data->base) {
		ret = -ENODEV;
		dev_err(&pdev->dev, "Failed to ioremap memory\n");
		goto err_mem_region;
	}

	ret = request_irq(data->irq, exynos4_tmu_irq,
		IRQF_TRIGGER_RISING,
		"exynos4-tmu", data);
	if (ret) {
		dev_err(&pdev->dev, "Failed to request irq: %d\n", data->irq);
		goto err_io_remap;
	}

	data->clk = clk_get(NULL, "tmu_apbif");
	if (IS_ERR(data->clk)) {
		ret = PTR_ERR(data->clk);
		dev_err(&pdev->dev, "Failed to get clock\n");
		goto err_irq;
	}

	data->pdata = pdata;
	platform_set_drvdata(pdev, data);
	mutex_init(&data->lock);

	ret = exynos4_tmu_initialize(pdev);
	if (ret) {
		dev_err(&pdev->dev, "Failed to initialize TMU\n");
		goto err_clk;
	}

	ret = sysfs_create_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
	if (ret) {
		dev_err(&pdev->dev, "Failed to create sysfs group\n");
		goto err_clk;
	}

	data->hwmon_dev = hwmon_device_register(&pdev->dev);
	if (IS_ERR(data->hwmon_dev)) {
		ret = PTR_ERR(data->hwmon_dev);
		dev_err(&pdev->dev, "Failed to register hwmon device\n");
		goto err_create_group;
	}

	exynos4_tmu_control(pdev, true);

	return 0;

err_create_group:
	sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
err_clk:
	platform_set_drvdata(pdev, NULL);
	clk_put(data->clk);
err_irq:
	free_irq(data->irq, data);
err_io_remap:
	iounmap(data->base);
err_mem_region:
	release_mem_region(data->mem->start, resource_size(data->mem));
err_free:
	kfree(data);

	return ret;
}

static int __devexit exynos4_tmu_remove(struct platform_device *pdev)
{
	struct exynos4_tmu_data *data = platform_get_drvdata(pdev);

	exynos4_tmu_control(pdev, false);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);

	clk_put(data->clk);

	free_irq(data->irq, data);

	iounmap(data->base);
	release_mem_region(data->mem->start, resource_size(data->mem));

	platform_set_drvdata(pdev, NULL);

	kfree(data);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int exynos4_tmu_suspend(struct device *dev)
{
	exynos4_tmu_control(to_platform_device(dev), false);

	return 0;
}

static int exynos4_tmu_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);

	exynos4_tmu_initialize(pdev);
	exynos4_tmu_control(pdev, true);

	return 0;
}

static SIMPLE_DEV_PM_OPS(exynos4_tmu_pm,
			 exynos4_tmu_suspend, exynos4_tmu_resume);
#define EXYNOS4_TMU_PM	&exynos4_tmu_pm
#else
#define EXYNOS4_TMU_PM	NULL
#endif

static struct platform_driver exynos4_tmu_driver = {
	.driver = {
		.name   = "exynos4-tmu",
		.owner  = THIS_MODULE,
		.pm     = EXYNOS4_TMU_PM,
	},
	.probe = exynos4_tmu_probe,
	.remove	= __devexit_p(exynos4_tmu_remove),
};

module_platform_driver(exynos4_tmu_driver);

MODULE_DESCRIPTION("EXYNOS4 TMU Driver");
MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:exynos4-tmu");