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Avoid beyond bounds copy while caching ACL
[zen-stable.git] / drivers / hwmon / exynos4_tmu.c
blobf2359a0093bd65e52c6985e6a06eef3a0cec8d37
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 */
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 */
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
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
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
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
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
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
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
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
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
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
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
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
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
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");