drivers/thermal/rcar_thermal.c

   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         u32 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         u32 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, int *temp)
 204 {
 205         struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
 206
 207         if (!rcar_has_irq_support(priv) || rcar_force_update_temp(priv))
 208                 rcar_thermal_update_temp(priv);
 209
 210         mutex_lock(&priv->lock);
 211         *temp =  MCELSIUS((priv->ctemp * 5) - 65);
 212         mutex_unlock(&priv->lock);
 213
 214         return 0;
 215 }
 216
 217 static int rcar_thermal_get_trip_type(struct thermal_zone_device *zone,
 218                                       int trip, enum thermal_trip_type *type)
 219 {
 220         struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
 221         struct device *dev = rcar_priv_to_dev(priv);
 222
 223         /* see rcar_thermal_get_temp() */
 224         switch (trip) {
 225         case 0: /* +90 <= temp */
 226                 *type = THERMAL_TRIP_CRITICAL;
 227                 break;
 228         default:
 229                 dev_err(dev, "rcar driver trip error\n");
 230                 return -EINVAL;
 231         }
 232
 233         return 0;
 234 }
 235
 236 static int rcar_thermal_get_trip_temp(struct thermal_zone_device *zone,
 237                                       int trip, int *temp)
 238 {
 239         struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
 240         struct device *dev = rcar_priv_to_dev(priv);
 241
 242         /* see rcar_thermal_get_temp() */
 243         switch (trip) {
 244         case 0: /* +90 <= temp */
 245                 *temp = MCELSIUS(90);
 246                 break;
 247         default:
 248                 dev_err(dev, "rcar driver trip error\n");
 249                 return -EINVAL;
 250         }
 251
 252         return 0;
 253 }
 254
 255 static int rcar_thermal_notify(struct thermal_zone_device *zone,
 256                                int trip, enum thermal_trip_type type)
 257 {
 258         struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
 259         struct device *dev = rcar_priv_to_dev(priv);
 260
 261         switch (type) {
 262         case THERMAL_TRIP_CRITICAL:
 263                 /* FIXME */
 264                 dev_warn(dev, "Thermal reached to critical temperature\n");
 265                 break;
 266         default:
 267                 break;
 268         }
 269
 270         return 0;
 271 }
 272
 273 static struct thermal_zone_device_ops rcar_thermal_zone_ops = {
 274         .get_temp       = rcar_thermal_get_temp,
 275         .get_trip_type  = rcar_thermal_get_trip_type,
 276         .get_trip_temp  = rcar_thermal_get_trip_temp,
 277         .notify         = rcar_thermal_notify,
 278 };
 279
 280 /*
 281  *              interrupt
 282  */
 283 #define rcar_thermal_irq_enable(p)      _rcar_thermal_irq_ctrl(p, 1)
 284 #define rcar_thermal_irq_disable(p)     _rcar_thermal_irq_ctrl(p, 0)
 285 static void _rcar_thermal_irq_ctrl(struct rcar_thermal_priv *priv, int enable)
 286 {
 287         struct rcar_thermal_common *common = priv->common;
 288         unsigned long flags;
 289         u32 mask = 0x3 << rcar_id_to_shift(priv); /* enable Rising/Falling */
 290
 291         spin_lock_irqsave(&common->lock, flags);
 292
 293         rcar_thermal_common_bset(common, INTMSK, mask, enable ? 0 : mask);
 294
 295         spin_unlock_irqrestore(&common->lock, flags);
 296 }
 297
 298 static void rcar_thermal_work(struct work_struct *work)
 299 {
 300         struct rcar_thermal_priv *priv;
 301         int cctemp, nctemp;
 302
 303         priv = container_of(work, struct rcar_thermal_priv, work.work);
 304
 305         rcar_thermal_get_temp(priv->zone, &cctemp);
 306         rcar_thermal_update_temp(priv);
 307         rcar_thermal_irq_enable(priv);
 308
 309         rcar_thermal_get_temp(priv->zone, &nctemp);
 310         if (nctemp != cctemp)
 311                 thermal_zone_device_update(priv->zone);
 312 }
 313
 314 static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
 315 {
 316         struct device *dev = rcar_priv_to_dev(priv);
 317
 318         status = (status >> rcar_id_to_shift(priv)) & 0x3;
 319
 320         if (status) {
 321                 dev_dbg(dev, "thermal%d %s%s\n",
 322                         priv->id,
 323                         (status & 0x2) ? "Rising " : "",
 324                         (status & 0x1) ? "Falling" : "");
 325         }
 326
 327         return status;
 328 }
 329
 330 static irqreturn_t rcar_thermal_irq(int irq, void *data)
 331 {
 332         struct rcar_thermal_common *common = data;
 333         struct rcar_thermal_priv *priv;
 334         unsigned long flags;
 335         u32 status, mask;
 336
 337         spin_lock_irqsave(&common->lock, flags);
 338
 339         mask    = rcar_thermal_common_read(common, INTMSK);
 340         status  = rcar_thermal_common_read(common, STR);
 341         rcar_thermal_common_write(common, STR, 0x000F0F0F & mask);
 342
 343         spin_unlock_irqrestore(&common->lock, flags);
 344
 345         status = status & ~mask;
 346
 347         /*
 348          * check the status
 349          */
 350         rcar_thermal_for_each_priv(priv, common) {
 351                 if (rcar_thermal_had_changed(priv, status)) {
 352                         rcar_thermal_irq_disable(priv);
 353                         schedule_delayed_work(&priv->work,
 354                                               msecs_to_jiffies(300));
 355                 }
 356         }
 357
 358         return IRQ_HANDLED;
 359 }
 360
 361 /*
 362  *              platform functions
 363  */
 364 static int rcar_thermal_remove(struct platform_device *pdev)
 365 {
 366         struct rcar_thermal_common *common = platform_get_drvdata(pdev);
 367         struct device *dev = &pdev->dev;
 368         struct rcar_thermal_priv *priv;
 369
 370         rcar_thermal_for_each_priv(priv, common) {
 371                 if (rcar_has_irq_support(priv))
 372                         rcar_thermal_irq_disable(priv);
 373                 thermal_zone_device_unregister(priv->zone);
 374         }
 375
 376         pm_runtime_put(dev);
 377         pm_runtime_disable(dev);
 378
 379         return 0;
 380 }
 381
 382 static int rcar_thermal_probe(struct platform_device *pdev)
 383 {
 384         struct rcar_thermal_common *common;
 385         struct rcar_thermal_priv *priv;
 386         struct device *dev = &pdev->dev;
 387         struct resource *res, *irq;
 388         int mres = 0;
 389         int i;
 390         int ret = -ENODEV;
 391         int idle = IDLE_INTERVAL;
 392         u32 enr_bits = 0;
 393
 394         common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
 395         if (!common)
 396                 return -ENOMEM;
 397
 398         platform_set_drvdata(pdev, common);
 399
 400         INIT_LIST_HEAD(&common->head);
 401         spin_lock_init(&common->lock);
 402         common->dev = dev;
 403
 404         pm_runtime_enable(dev);
 405         pm_runtime_get_sync(dev);
 406
 407         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 408         if (irq) {
 409                 /*
 410                  * platform has IRQ support.
 411                  * Then, driver uses common registers
 412                  * rcar_has_irq_support() will be enabled
 413                  */
 414                 res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
 415                 common->base = devm_ioremap_resource(dev, res);
 416                 if (IS_ERR(common->base))
 417                         return PTR_ERR(common->base);
 418
 419                 idle = 0; /* polling delay is not needed */
 420         }
 421
 422         for (i = 0;; i++) {
 423                 res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
 424                 if (!res)
 425                         break;
 426
 427                 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 428                 if (!priv) {
 429                         ret = -ENOMEM;
 430                         goto error_unregister;
 431                 }
 432
 433                 priv->base = devm_ioremap_resource(dev, res);
 434                 if (IS_ERR(priv->base)) {
 435                         ret = PTR_ERR(priv->base);
 436                         goto error_unregister;
 437                 }
 438
 439                 priv->common = common;
 440                 priv->id = i;
 441                 mutex_init(&priv->lock);
 442                 INIT_LIST_HEAD(&priv->list);
 443                 INIT_DELAYED_WORK(&priv->work, rcar_thermal_work);
 444                 rcar_thermal_update_temp(priv);
 445
 446                 priv->zone = thermal_zone_device_register("rcar_thermal",
 447                                                 1, 0, priv,
 448                                                 &rcar_thermal_zone_ops, NULL, 0,
 449                                                 idle);
 450                 if (IS_ERR(priv->zone)) {
 451                         dev_err(dev, "can't register thermal zone\n");
 452                         ret = PTR_ERR(priv->zone);
 453                         goto error_unregister;
 454                 }
 455
 456                 if (rcar_has_irq_support(priv))
 457                         rcar_thermal_irq_enable(priv);
 458
 459                 list_move_tail(&priv->list, &common->head);
 460
 461                 /* update ENR bits */
 462                 enr_bits |= 3 << (i * 8);
 463         }
 464
 465         /* enable temperature comparation */
 466         if (irq) {
 467                 ret = devm_request_irq(dev, irq->start, rcar_thermal_irq, 0,
 468                                        dev_name(dev), common);
 469                 if (ret) {
 470                         dev_err(dev, "irq request failed\n ");
 471                         goto error_unregister;
 472                 }
 473
 474                 rcar_thermal_common_write(common, ENR, enr_bits);
 475         }
 476
 477         dev_info(dev, "%d sensor probed\n", i);
 478
 479         return 0;
 480
 481 error_unregister:
 482         rcar_thermal_remove(pdev);
 483
 484         return ret;
 485 }
 486
 487 static const struct of_device_id rcar_thermal_dt_ids[] = {
 488         { .compatible = "renesas,rcar-thermal", },
 489         {},
 490 };
 491 MODULE_DEVICE_TABLE(of, rcar_thermal_dt_ids);
 492
 493 static struct platform_driver rcar_thermal_driver = {
 494         .driver = {
 495                 .name   = "rcar_thermal",
 496                 .of_match_table = rcar_thermal_dt_ids,
 497         },
 498         .probe          = rcar_thermal_probe,
 499         .remove         = rcar_thermal_remove,
 500 };
 501 module_platform_driver(rcar_thermal_driver);
 502
 503 MODULE_LICENSE("GPL");
 504 MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver");
 505 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");