linux/drivers/thermal/rcar_thermal.c
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   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/reboot.h>
  28#include <linux/slab.h>
  29#include <linux/spinlock.h>
  30#include <linux/thermal.h>
  31
  32#define IDLE_INTERVAL   5000
  33
  34#define COMMON_STR      0x00
  35#define COMMON_ENR      0x04
  36#define COMMON_INTMSK   0x0c
  37
  38#define REG_POSNEG      0x20
  39#define REG_FILONOFF    0x28
  40#define REG_THSCR       0x2c
  41#define REG_THSSR       0x30
  42#define REG_INTCTRL     0x34
  43
  44/* THSCR */
  45#define CPCTL   (1 << 12)
  46
  47/* THSSR */
  48#define CTEMP   0x3f
  49
  50struct rcar_thermal_common {
  51        void __iomem *base;
  52        struct device *dev;
  53        struct list_head head;
  54        spinlock_t lock;
  55};
  56
  57struct rcar_thermal_priv {
  58        void __iomem *base;
  59        struct rcar_thermal_common *common;
  60        struct thermal_zone_device *zone;
  61        struct delayed_work work;
  62        struct mutex lock;
  63        struct list_head list;
  64        int id;
  65        int ctemp;
  66};
  67
  68#define rcar_thermal_for_each_priv(pos, common) \
  69        list_for_each_entry(pos, &common->head, list)
  70
  71#define MCELSIUS(temp)                  ((temp) * 1000)
  72#define rcar_zone_to_priv(zone)         ((zone)->devdata)
  73#define rcar_priv_to_dev(priv)          ((priv)->common->dev)
  74#define rcar_has_irq_support(priv)      ((priv)->common->base)
  75#define rcar_id_to_shift(priv)          ((priv)->id * 8)
  76
  77#ifdef DEBUG
  78# define rcar_force_update_temp(priv)   1
  79#else
  80# define rcar_force_update_temp(priv)   0
  81#endif
  82
  83/*
  84 *              basic functions
  85 */
  86#define rcar_thermal_common_read(c, r) \
  87        _rcar_thermal_common_read(c, COMMON_ ##r)
  88static u32 _rcar_thermal_common_read(struct rcar_thermal_common *common,
  89                                     u32 reg)
  90{
  91        return ioread32(common->base + reg);
  92}
  93
  94#define rcar_thermal_common_write(c, r, d) \
  95        _rcar_thermal_common_write(c, COMMON_ ##r, d)
  96static void _rcar_thermal_common_write(struct rcar_thermal_common *common,
  97                                       u32 reg, u32 data)
  98{
  99        iowrite32(data, common->base + reg);
 100}
 101
 102#define rcar_thermal_common_bset(c, r, m, d) \
 103        _rcar_thermal_common_bset(c, COMMON_ ##r, m, d)
 104static void _rcar_thermal_common_bset(struct rcar_thermal_common *common,
 105                                      u32 reg, u32 mask, u32 data)
 106{
 107        u32 val;
 108
 109        val = ioread32(common->base + reg);
 110        val &= ~mask;
 111        val |= (data & mask);
 112        iowrite32(val, common->base + reg);
 113}
 114
 115#define rcar_thermal_read(p, r) _rcar_thermal_read(p, REG_ ##r)
 116static u32 _rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg)
 117{
 118        return ioread32(priv->base + reg);
 119}
 120
 121#define rcar_thermal_write(p, r, d) _rcar_thermal_write(p, REG_ ##r, d)
 122static void _rcar_thermal_write(struct rcar_thermal_priv *priv,
 123                                u32 reg, u32 data)
 124{
 125        iowrite32(data, priv->base + reg);
 126}
 127
 128#define rcar_thermal_bset(p, r, m, d) _rcar_thermal_bset(p, REG_ ##r, m, d)
 129static void _rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg,
 130                               u32 mask, u32 data)
 131{
 132        u32 val;
 133
 134        val = ioread32(priv->base + reg);
 135        val &= ~mask;
 136        val |= (data & mask);
 137        iowrite32(val, priv->base + reg);
 138}
 139
 140/*
 141 *              zone device functions
 142 */
 143static int rcar_thermal_update_temp(struct rcar_thermal_priv *priv)
 144{
 145        struct device *dev = rcar_priv_to_dev(priv);
 146        int i;
 147        int ctemp, old, new;
 148        int ret = -EINVAL;
 149
 150        mutex_lock(&priv->lock);
 151
 152        /*
 153         * TSC decides a value of CPTAP automatically,
 154         * and this is the conditions which validate interrupt.
 155         */
 156        rcar_thermal_bset(priv, THSCR, CPCTL, CPCTL);
 157
 158        ctemp = 0;
 159        old = ~0;
 160        for (i = 0; i < 128; i++) {
 161                /*
 162                 * we need to wait 300us after changing comparator offset
 163                 * to get stable temperature.
 164                 * see "Usage Notes" on datasheet
 165                 */
 166                udelay(300);
 167
 168                new = rcar_thermal_read(priv, THSSR) & CTEMP;
 169                if (new == old) {
 170                        ctemp = new;
 171                        break;
 172                }
 173                old = new;
 174        }
 175
 176        if (!ctemp) {
 177                dev_err(dev, "thermal sensor was broken\n");
 178                goto err_out_unlock;
 179        }
 180
 181        /*
 182         * enable IRQ
 183         */
 184        if (rcar_has_irq_support(priv)) {
 185                rcar_thermal_write(priv, FILONOFF, 0);
 186
 187                /* enable Rising/Falling edge interrupt */
 188                rcar_thermal_write(priv, POSNEG,  0x1);
 189                rcar_thermal_write(priv, INTCTRL, (((ctemp - 0) << 8) |
 190                                                   ((ctemp - 1) << 0)));
 191        }
 192
 193        dev_dbg(dev, "thermal%d  %d -> %d\n", priv->id, priv->ctemp, ctemp);
 194
 195        priv->ctemp = ctemp;
 196        ret = 0;
 197err_out_unlock:
 198        mutex_unlock(&priv->lock);
 199        return ret;
 200}
 201
 202static int rcar_thermal_get_temp(struct thermal_zone_device *zone,
 203                                 unsigned long *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
 217static 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
 236static int rcar_thermal_get_trip_temp(struct thermal_zone_device *zone,
 237                                      int trip, unsigned long *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
 255static 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
 273static 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)
 285static 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
 298static void rcar_thermal_work(struct work_struct *work)
 299{
 300        struct rcar_thermal_priv *priv;
 301
 302        priv = container_of(work, struct rcar_thermal_priv, work.work);
 303
 304        rcar_thermal_update_temp(priv);
 305        rcar_thermal_irq_enable(priv);
 306        thermal_zone_device_update(priv->zone);
 307}
 308
 309static u32 rcar_thermal_had_changed(struct rcar_thermal_priv *priv, u32 status)
 310{
 311        struct device *dev = rcar_priv_to_dev(priv);
 312
 313        status = (status >> rcar_id_to_shift(priv)) & 0x3;
 314
 315        if (status & 0x3) {
 316                dev_dbg(dev, "thermal%d %s%s\n",
 317                        priv->id,
 318                        (status & 0x2) ? "Rising " : "",
 319                        (status & 0x1) ? "Falling" : "");
 320        }
 321
 322        return status;
 323}
 324
 325static irqreturn_t rcar_thermal_irq(int irq, void *data)
 326{
 327        struct rcar_thermal_common *common = data;
 328        struct rcar_thermal_priv *priv;
 329        unsigned long flags;
 330        u32 status, mask;
 331
 332        spin_lock_irqsave(&common->lock, flags);
 333
 334        mask    = rcar_thermal_common_read(common, INTMSK);
 335        status  = rcar_thermal_common_read(common, STR);
 336        rcar_thermal_common_write(common, STR, 0x000F0F0F & mask);
 337
 338        spin_unlock_irqrestore(&common->lock, flags);
 339
 340        status = status & ~mask;
 341
 342        /*
 343         * check the status
 344         */
 345        rcar_thermal_for_each_priv(priv, common) {
 346                if (rcar_thermal_had_changed(priv, status)) {
 347                        rcar_thermal_irq_disable(priv);
 348                        schedule_delayed_work(&priv->work,
 349                                              msecs_to_jiffies(300));
 350                }
 351        }
 352
 353        return IRQ_HANDLED;
 354}
 355
 356/*
 357 *              platform functions
 358 */
 359static int rcar_thermal_probe(struct platform_device *pdev)
 360{
 361        struct rcar_thermal_common *common;
 362        struct rcar_thermal_priv *priv;
 363        struct device *dev = &pdev->dev;
 364        struct resource *res, *irq;
 365        int mres = 0;
 366        int i;
 367        int ret = -ENODEV;
 368        int idle = IDLE_INTERVAL;
 369
 370        common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
 371        if (!common) {
 372                dev_err(dev, "Could not allocate common\n");
 373                return -ENOMEM;
 374        }
 375
 376        INIT_LIST_HEAD(&common->head);
 377        spin_lock_init(&common->lock);
 378        common->dev = dev;
 379
 380        irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 381        if (irq) {
 382                int ret;
 383
 384                /*
 385                 * platform has IRQ support.
 386                 * Then, drier use common register
 387                 */
 388                res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
 389                if (!res) {
 390                        dev_err(dev, "Could not get platform resource\n");
 391                        return -ENODEV;
 392                }
 393
 394                ret = devm_request_irq(dev, irq->start, rcar_thermal_irq, 0,
 395                                       dev_name(dev), common);
 396                if (ret) {
 397                        dev_err(dev, "irq request failed\n ");
 398                        return ret;
 399                }
 400
 401                /*
 402                 * rcar_has_irq_support() will be enabled
 403                 */
 404                common->base = devm_ioremap_resource(dev, res);
 405                if (IS_ERR(common->base))
 406                        return PTR_ERR(common->base);
 407
 408                /* enable temperature comparation */
 409                rcar_thermal_common_write(common, ENR, 0x00030303);
 410
 411                idle = 0; /* polling delaye is not needed */
 412        }
 413
 414        for (i = 0;; i++) {
 415                res = platform_get_resource(pdev, IORESOURCE_MEM, mres++);
 416                if (!res)
 417                        break;
 418
 419                priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 420                if (!priv) {
 421                        dev_err(dev, "Could not allocate priv\n");
 422                        return -ENOMEM;
 423                }
 424
 425                priv->base = devm_ioremap_resource(dev, res);
 426                if (IS_ERR(priv->base))
 427                        return PTR_ERR(priv->base);
 428
 429                priv->common = common;
 430                priv->id = i;
 431                mutex_init(&priv->lock);
 432                INIT_LIST_HEAD(&priv->list);
 433                INIT_DELAYED_WORK(&priv->work, rcar_thermal_work);
 434                rcar_thermal_update_temp(priv);
 435
 436                priv->zone = thermal_zone_device_register("rcar_thermal",
 437                                                1, 0, priv,
 438                                                &rcar_thermal_zone_ops, NULL, 0,
 439                                                idle);
 440                if (IS_ERR(priv->zone)) {
 441                        dev_err(dev, "can't register thermal zone\n");
 442                        ret = PTR_ERR(priv->zone);
 443                        goto error_unregister;
 444                }
 445
 446                list_move_tail(&priv->list, &common->head);
 447
 448                if (rcar_has_irq_support(priv))
 449                        rcar_thermal_irq_enable(priv);
 450        }
 451
 452        platform_set_drvdata(pdev, common);
 453
 454        dev_info(dev, "%d sensor proved\n", i);
 455
 456        return 0;
 457
 458error_unregister:
 459        rcar_thermal_for_each_priv(priv, common)
 460                thermal_zone_device_unregister(priv->zone);
 461
 462        return ret;
 463}
 464
 465static int rcar_thermal_remove(struct platform_device *pdev)
 466{
 467        struct rcar_thermal_common *common = platform_get_drvdata(pdev);
 468        struct rcar_thermal_priv *priv;
 469
 470        rcar_thermal_for_each_priv(priv, common)
 471                thermal_zone_device_unregister(priv->zone);
 472
 473        platform_set_drvdata(pdev, NULL);
 474
 475        return 0;
 476}
 477
 478static const struct of_device_id rcar_thermal_dt_ids[] = {
 479        { .compatible = "renesas,rcar-thermal", },
 480        {},
 481};
 482MODULE_DEVICE_TABLE(of, rcar_thermal_dt_ids);
 483
 484static struct platform_driver rcar_thermal_driver = {
 485        .driver = {
 486                .name   = "rcar_thermal",
 487                .of_match_table = rcar_thermal_dt_ids,
 488        },
 489        .probe          = rcar_thermal_probe,
 490        .remove         = rcar_thermal_remove,
 491};
 492module_platform_driver(rcar_thermal_driver);
 493
 494MODULE_LICENSE("GPL");
 495MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver");
 496MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
 497
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