drivers/hwmon/exynos4_tmu.c

   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");