arch/arm/mach-omap2/smartreflex.c

   1 /*
   2  * OMAP SmartReflex Voltage Control
   3  *
   4  * Author: Thara Gopinath       <thara@ti.com>
   5  *
   6  * Copyright (C) 2010 Texas Instruments, Inc.
   7  * Thara Gopinath <thara@ti.com>
   8  *
   9  * Copyright (C) 2008 Nokia Corporation
  10  * Kalle Jokiniemi
  11  *
  12  * Copyright (C) 2007 Texas Instruments, Inc.
  13  * Lesly A M <x0080970@ti.com>
  14  *
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License version 2 as
  17  * published by the Free Software Foundation.
  18  */
  19
  20 #include <linux/interrupt.h>
  21 #include <linux/clk.h>
  22 #include <linux/io.h>
  23 #include <linux/debugfs.h>
  24 #include <linux/delay.h>
  25 #include <linux/slab.h>
  26 #include <linux/pm_runtime.h>
  27
  28 #include <plat/common.h>
  29
  30 #include "pm.h"
  31 #include "smartreflex.h"
  32
  33 #define SMARTREFLEX_NAME_LEN    16
  34 #define NVALUE_NAME_LEN         40
  35 #define SR_DISABLE_TIMEOUT      200
  36
  37 struct omap_sr {
  38         int                             srid;
  39         int                             ip_type;
  40         int                             nvalue_count;
  41         bool                            autocomp_active;
  42         u32                             clk_length;
  43         u32                             err_weight;
  44         u32                             err_minlimit;
  45         u32                             err_maxlimit;
  46         u32                             accum_data;
  47         u32                             senn_avgweight;
  48         u32                             senp_avgweight;
  49         u32                             senp_mod;
  50         u32                             senn_mod;
  51         unsigned int                    irq;
  52         void __iomem                    *base;
  53         struct platform_device          *pdev;
  54         struct list_head                node;
  55         struct omap_sr_nvalue_table     *nvalue_table;
  56         struct voltagedomain            *voltdm;
  57         struct dentry                   *dbg_dir;
  58 };
  59
  60 /* sr_list contains all the instances of smartreflex module */
  61 static LIST_HEAD(sr_list);
  62
  63 static struct omap_sr_class_data *sr_class;
  64 static struct omap_sr_pmic_data *sr_pmic_data;
  65
  66 static inline void sr_write_reg(struct omap_sr *sr, unsigned offset, u32 value)
  67 {
  68         __raw_writel(value, (sr->base + offset));
  69 }
  70
  71 static inline void sr_modify_reg(struct omap_sr *sr, unsigned offset, u32 mask,
  72                                         u32 value)
  73 {
  74         u32 reg_val;
  75         u32 errconfig_offs = 0, errconfig_mask = 0;
  76
  77         reg_val = __raw_readl(sr->base + offset);
  78         reg_val &= ~mask;
  79
  80         /*
  81          * Smartreflex error config register is special as it contains
  82          * certain status bits which if written a 1 into means a clear
  83          * of those bits. So in order to make sure no accidental write of
  84          * 1 happens to those status bits, do a clear of them in the read
  85          * value. This mean this API doesn't rewrite values in these bits
  86          * if they are currently set, but does allow the caller to write
  87          * those bits.
  88          */
  89         if (sr->ip_type == SR_TYPE_V1) {
  90                 errconfig_offs = ERRCONFIG_V1;
  91                 errconfig_mask = ERRCONFIG_STATUS_V1_MASK;
  92         } else if (sr->ip_type == SR_TYPE_V2) {
  93                 errconfig_offs = ERRCONFIG_V2;
  94                 errconfig_mask = ERRCONFIG_VPBOUNDINTST_V2;
  95         }
  96
  97         if (offset == errconfig_offs)
  98                 reg_val &= ~errconfig_mask;
  99
 100         reg_val |= value;
 101
 102         __raw_writel(reg_val, (sr->base + offset));
 103 }
 104
 105 static inline u32 sr_read_reg(struct omap_sr *sr, unsigned offset)
 106 {
 107         return __raw_readl(sr->base + offset);
 108 }
 109
 110 static struct omap_sr *_sr_lookup(struct voltagedomain *voltdm)
 111 {
 112         struct omap_sr *sr_info;
 113
 114         if (!voltdm) {
 115                 pr_err("%s: Null voltage domain passed!\n", __func__);
 116                 return ERR_PTR(-EINVAL);
 117         }
 118
 119         list_for_each_entry(sr_info, &sr_list, node) {
 120                 if (voltdm == sr_info->voltdm)
 121                         return sr_info;
 122         }
 123
 124         return ERR_PTR(-ENODATA);
 125 }
 126
 127 static irqreturn_t sr_interrupt(int irq, void *data)
 128 {
 129         struct omap_sr *sr_info = (struct omap_sr *)data;
 130         u32 status = 0;
 131
 132         if (sr_info->ip_type == SR_TYPE_V1) {
 133                 /* Read the status bits */
 134                 status = sr_read_reg(sr_info, ERRCONFIG_V1);
 135
 136                 /* Clear them by writing back */
 137                 sr_write_reg(sr_info, ERRCONFIG_V1, status);
 138         } else if (sr_info->ip_type == SR_TYPE_V2) {
 139                 /* Read the status bits */
 140                 sr_read_reg(sr_info, IRQSTATUS);
 141
 142                 /* Clear them by writing back */
 143                 sr_write_reg(sr_info, IRQSTATUS, status);
 144         }
 145
 146         if (sr_class->notify)
 147                 sr_class->notify(sr_info->voltdm, status);
 148
 149         return IRQ_HANDLED;
 150 }
 151
 152 static void sr_set_clk_length(struct omap_sr *sr)
 153 {
 154         struct clk *sys_ck;
 155         u32 sys_clk_speed;
 156
 157         if (cpu_is_omap34xx())
 158                 sys_ck = clk_get(NULL, "sys_ck");
 159         else
 160                 sys_ck = clk_get(NULL, "sys_clkin_ck");
 161
 162         if (IS_ERR(sys_ck)) {
 163                 dev_err(&sr->pdev->dev, "%s: unable to get sys clk\n",
 164                         __func__);
 165                 return;
 166         }
 167         sys_clk_speed = clk_get_rate(sys_ck);
 168         clk_put(sys_ck);
 169
 170         switch (sys_clk_speed) {
 171         case 12000000:
 172                 sr->clk_length = SRCLKLENGTH_12MHZ_SYSCLK;
 173                 break;
 174         case 13000000:
 175                 sr->clk_length = SRCLKLENGTH_13MHZ_SYSCLK;
 176                 break;
 177         case 19200000:
 178                 sr->clk_length = SRCLKLENGTH_19MHZ_SYSCLK;
 179                 break;
 180         case 26000000:
 181                 sr->clk_length = SRCLKLENGTH_26MHZ_SYSCLK;
 182                 break;
 183         case 38400000:
 184                 sr->clk_length = SRCLKLENGTH_38MHZ_SYSCLK;
 185                 break;
 186         default:
 187                 dev_err(&sr->pdev->dev, "%s: Invalid sysclk value: %d\n",
 188                         __func__, sys_clk_speed);
 189                 break;
 190         }
 191 }
 192
 193 static void sr_set_regfields(struct omap_sr *sr)
 194 {
 195         /*
 196          * For time being these values are defined in smartreflex.h
 197          * and populated during init. May be they can be moved to board
 198          * file or pmic specific data structure. In that case these structure
 199          * fields will have to be populated using the pdata or pmic structure.
 200          */
 201         if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
 202                 sr->err_weight = OMAP3430_SR_ERRWEIGHT;
 203                 sr->err_maxlimit = OMAP3430_SR_ERRMAXLIMIT;
 204                 sr->accum_data = OMAP3430_SR_ACCUMDATA;
 205                 if (!(strcmp(sr->voltdm->name, "mpu"))) {
 206                         sr->senn_avgweight = OMAP3430_SR1_SENNAVGWEIGHT;
 207                         sr->senp_avgweight = OMAP3430_SR1_SENPAVGWEIGHT;
 208                 } else {
 209                         sr->senn_avgweight = OMAP3430_SR2_SENNAVGWEIGHT;
 210                         sr->senp_avgweight = OMAP3430_SR2_SENPAVGWEIGHT;
 211                 }
 212         }
 213 }
 214
 215 static void sr_start_vddautocomp(struct omap_sr *sr)
 216 {
 217         if (!sr_class || !(sr_class->enable) || !(sr_class->configure)) {
 218                 dev_warn(&sr->pdev->dev,
 219                         "%s: smartreflex class driver not registered\n",
 220                         __func__);
 221                 return;
 222         }
 223
 224         if (!sr_class->enable(sr->voltdm))
 225                 sr->autocomp_active = true;
 226 }
 227
 228 static void sr_stop_vddautocomp(struct omap_sr *sr)
 229 {
 230         if (!sr_class || !(sr_class->disable)) {
 231                 dev_warn(&sr->pdev->dev,
 232                         "%s: smartreflex class driver not registered\n",
 233                         __func__);
 234                 return;
 235         }
 236
 237         if (sr->autocomp_active) {
 238                 sr_class->disable(sr->voltdm, 1);
 239                 sr->autocomp_active = false;
 240         }
 241 }
 242
 243 /*
 244  * This function handles the intializations which have to be done
 245  * only when both sr device and class driver regiter has
 246  * completed. This will be attempted to be called from both sr class
 247  * driver register and sr device intializtion API's. Only one call
 248  * will ultimately succeed.
 249  *
 250  * Currently this function registers interrupt handler for a particular SR
 251  * if smartreflex class driver is already registered and has
 252  * requested for interrupts and the SR interrupt line in present.
 253  */
 254 static int sr_late_init(struct omap_sr *sr_info)
 255 {
 256         char *name;
 257         struct omap_sr_data *pdata = sr_info->pdev->dev.platform_data;
 258         struct resource *mem;
 259         int ret = 0;
 260
 261         if (sr_class->notify && sr_class->notify_flags && sr_info->irq) {
 262                 name = kasprintf(GFP_KERNEL, "sr_%s", sr_info->voltdm->name);
 263                 if (name == NULL) {
 264                         ret = -ENOMEM;
 265                         goto error;
 266                 }
 267                 ret = request_irq(sr_info->irq, sr_interrupt,
 268                                 0, name, (void *)sr_info);
 269                 if (ret)
 270                         goto error;
 271                 disable_irq(sr_info->irq);
 272         }
 273
 274         if (pdata && pdata->enable_on_init)
 275                 sr_start_vddautocomp(sr_info);
 276
 277         return ret;
 278
 279 error:
 280         iounmap(sr_info->base);
 281         mem = platform_get_resource(sr_info->pdev, IORESOURCE_MEM, 0);
 282         release_mem_region(mem->start, resource_size(mem));
 283         list_del(&sr_info->node);
 284         dev_err(&sr_info->pdev->dev, "%s: ERROR in registering"
 285                 "interrupt handler. Smartreflex will"
 286                 "not function as desired\n", __func__);
 287         kfree(name);
 288         kfree(sr_info);
 289         return ret;
 290 }
 291
 292 static void sr_v1_disable(struct omap_sr *sr)
 293 {
 294         int timeout = 0;
 295
 296         /* Enable MCUDisableAcknowledge interrupt */
 297         sr_modify_reg(sr, ERRCONFIG_V1,
 298                         ERRCONFIG_MCUDISACKINTEN, ERRCONFIG_MCUDISACKINTEN);
 299
 300         /* SRCONFIG - disable SR */
 301         sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, 0x0);
 302
 303         /* Disable all other SR interrupts and clear the status */
 304         sr_modify_reg(sr, ERRCONFIG_V1,
 305                         (ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUVALIDINTEN |
 306                         ERRCONFIG_MCUBOUNDINTEN | ERRCONFIG_VPBOUNDINTEN_V1),
 307                         (ERRCONFIG_MCUACCUMINTST | ERRCONFIG_MCUVALIDINTST |
 308                         ERRCONFIG_MCUBOUNDINTST |
 309                         ERRCONFIG_VPBOUNDINTST_V1));
 310
 311         /*
 312          * Wait for SR to be disabled.
 313          * wait until ERRCONFIG.MCUDISACKINTST = 1. Typical latency is 1us.
 314          */
 315         omap_test_timeout((sr_read_reg(sr, ERRCONFIG_V1) &
 316                         ERRCONFIG_MCUDISACKINTST), SR_DISABLE_TIMEOUT,
 317                         timeout);
 318
 319         if (timeout >= SR_DISABLE_TIMEOUT)
 320                 dev_warn(&sr->pdev->dev, "%s: Smartreflex disable timedout\n",
 321                         __func__);
 322
 323         /* Disable MCUDisableAcknowledge interrupt & clear pending interrupt */
 324         sr_modify_reg(sr, ERRCONFIG_V1, ERRCONFIG_MCUDISACKINTEN,
 325                         ERRCONFIG_MCUDISACKINTST);
 326 }
 327
 328 static void sr_v2_disable(struct omap_sr *sr)
 329 {
 330         int timeout = 0;
 331
 332         /* Enable MCUDisableAcknowledge interrupt */
 333         sr_write_reg(sr, IRQENABLE_SET, IRQENABLE_MCUDISABLEACKINT);
 334
 335         /* SRCONFIG - disable SR */
 336         sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, 0x0);
 337
 338         /* Disable all other SR interrupts and clear the status */
 339         sr_modify_reg(sr, ERRCONFIG_V2, ERRCONFIG_VPBOUNDINTEN_V2,
 340                         ERRCONFIG_VPBOUNDINTST_V2);
 341         sr_write_reg(sr, IRQENABLE_CLR, (IRQENABLE_MCUACCUMINT |
 342                         IRQENABLE_MCUVALIDINT |
 343                         IRQENABLE_MCUBOUNDSINT));
 344         sr_write_reg(sr, IRQSTATUS, (IRQSTATUS_MCUACCUMINT |
 345                         IRQSTATUS_MCVALIDINT |
 346                         IRQSTATUS_MCBOUNDSINT));
 347
 348         /*
 349          * Wait for SR to be disabled.
 350          * wait until IRQSTATUS.MCUDISACKINTST = 1. Typical latency is 1us.
 351          */
 352         omap_test_timeout((sr_read_reg(sr, IRQSTATUS) &
 353                         IRQSTATUS_MCUDISABLEACKINT), SR_DISABLE_TIMEOUT,
 354                         timeout);
 355
 356         if (timeout >= SR_DISABLE_TIMEOUT)
 357                 dev_warn(&sr->pdev->dev, "%s: Smartreflex disable timedout\n",
 358                         __func__);
 359
 360         /* Disable MCUDisableAcknowledge interrupt & clear pending interrupt */
 361         sr_write_reg(sr, IRQENABLE_CLR, IRQENABLE_MCUDISABLEACKINT);
 362         sr_write_reg(sr, IRQSTATUS, IRQSTATUS_MCUDISABLEACKINT);
 363 }
 364
 365 static u32 sr_retrieve_nvalue(struct omap_sr *sr, u32 efuse_offs)
 366 {
 367         int i;
 368
 369         if (!sr->nvalue_table) {
 370                 dev_warn(&sr->pdev->dev, "%s: Missing ntarget value table\n",
 371                         __func__);
 372                 return 0;
 373         }
 374
 375         for (i = 0; i < sr->nvalue_count; i++) {
 376                 if (sr->nvalue_table[i].efuse_offs == efuse_offs)
 377                         return sr->nvalue_table[i].nvalue;
 378         }
 379
 380         return 0;
 381 }
 382
 383 /* Public Functions */
 384
 385 /**
 386  * sr_configure_errgen() - Configures the smrtreflex to perform AVS using the
 387  *                       error generator module.
 388  * @voltdm:     VDD pointer to which the SR module to be configured belongs to.
 389  *
 390  * This API is to be called from the smartreflex class driver to
 391  * configure the error generator module inside the smartreflex module.
 392  * SR settings if using the ERROR module inside Smartreflex.
 393  * SR CLASS 3 by default uses only the ERROR module where as
 394  * SR CLASS 2 can choose between ERROR module and MINMAXAVG
 395  * module. Returns 0 on success and error value in case of failure.
 396  */
 397 int sr_configure_errgen(struct voltagedomain *voltdm)
 398 {
 399         u32 sr_config, sr_errconfig, errconfig_offs, vpboundint_en;
 400         u32 vpboundint_st, senp_en = 0, senn_en = 0;
 401         u8 senp_shift, senn_shift;
 402         struct omap_sr *sr = _sr_lookup(voltdm);
 403
 404         if (IS_ERR(sr)) {
 405                 pr_warning("%s: omap_sr struct for sr_%s not found\n",
 406                         __func__, voltdm->name);
 407                 return -EINVAL;
 408         }
 409
 410         if (!sr->clk_length)
 411                 sr_set_clk_length(sr);
 412
 413         senp_en = sr->senp_mod;
 414         senn_en = sr->senn_mod;
 415
 416         sr_config = (sr->clk_length << SRCONFIG_SRCLKLENGTH_SHIFT) |
 417                 SRCONFIG_SENENABLE | SRCONFIG_ERRGEN_EN;
 418
 419         if (sr->ip_type == SR_TYPE_V1) {
 420                 sr_config |= SRCONFIG_DELAYCTRL;
 421                 senn_shift = SRCONFIG_SENNENABLE_V1_SHIFT;
 422                 senp_shift = SRCONFIG_SENPENABLE_V1_SHIFT;
 423                 errconfig_offs = ERRCONFIG_V1;
 424                 vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V1;
 425                 vpboundint_st = ERRCONFIG_VPBOUNDINTST_V1;
 426         } else if (sr->ip_type == SR_TYPE_V2) {
 427                 senn_shift = SRCONFIG_SENNENABLE_V2_SHIFT;
 428                 senp_shift = SRCONFIG_SENPENABLE_V2_SHIFT;
 429                 errconfig_offs = ERRCONFIG_V2;
 430                 vpboundint_en = ERRCONFIG_VPBOUNDINTEN_V2;
 431                 vpboundint_st = ERRCONFIG_VPBOUNDINTST_V2;
 432         } else {
 433                 dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex"
 434                         "module without specifying the ip\n", __func__);
 435                 return -EINVAL;
 436         }
 437
 438         sr_config |= ((senn_en << senn_shift) | (senp_en << senp_shift));
 439         sr_write_reg(sr, SRCONFIG, sr_config);
 440         sr_errconfig = (sr->err_weight << ERRCONFIG_ERRWEIGHT_SHIFT) |
 441                 (sr->err_maxlimit << ERRCONFIG_ERRMAXLIMIT_SHIFT) |
 442                 (sr->err_minlimit <<  ERRCONFIG_ERRMINLIMIT_SHIFT);
 443         sr_modify_reg(sr, errconfig_offs, (SR_ERRWEIGHT_MASK |
 444                 SR_ERRMAXLIMIT_MASK | SR_ERRMINLIMIT_MASK),
 445                 sr_errconfig);
 446
 447         /* Enabling the interrupts if the ERROR module is used */
 448         sr_modify_reg(sr, errconfig_offs,
 449                 vpboundint_en, (vpboundint_en | vpboundint_st));
 450
 451         return 0;
 452 }
 453
 454 /**
 455  * sr_configure_minmax() - Configures the smrtreflex to perform AVS using the
 456  *                       minmaxavg module.
 457  * @voltdm:     VDD pointer to which the SR module to be configured belongs to.
 458  *
 459  * This API is to be called from the smartreflex class driver to
 460  * configure the minmaxavg module inside the smartreflex module.
 461  * SR settings if using the ERROR module inside Smartreflex.
 462  * SR CLASS 3 by default uses only the ERROR module where as
 463  * SR CLASS 2 can choose between ERROR module and MINMAXAVG
 464  * module. Returns 0 on success and error value in case of failure.
 465  */
 466 int sr_configure_minmax(struct voltagedomain *voltdm)
 467 {
 468         u32 sr_config, sr_avgwt;
 469         u32 senp_en = 0, senn_en = 0;
 470         u8 senp_shift, senn_shift;
 471         struct omap_sr *sr = _sr_lookup(voltdm);
 472
 473         if (IS_ERR(sr)) {
 474                 pr_warning("%s: omap_sr struct for sr_%s not found\n",
 475                         __func__, voltdm->name);
 476                 return -EINVAL;
 477         }
 478
 479         if (!sr->clk_length)
 480                 sr_set_clk_length(sr);
 481
 482         senp_en = sr->senp_mod;
 483         senn_en = sr->senn_mod;
 484
 485         sr_config = (sr->clk_length << SRCONFIG_SRCLKLENGTH_SHIFT) |
 486                 SRCONFIG_SENENABLE |
 487                 (sr->accum_data << SRCONFIG_ACCUMDATA_SHIFT);
 488
 489         if (sr->ip_type == SR_TYPE_V1) {
 490                 sr_config |= SRCONFIG_DELAYCTRL;
 491                 senn_shift = SRCONFIG_SENNENABLE_V1_SHIFT;
 492                 senp_shift = SRCONFIG_SENPENABLE_V1_SHIFT;
 493         } else if (sr->ip_type == SR_TYPE_V2) {
 494                 senn_shift = SRCONFIG_SENNENABLE_V2_SHIFT;
 495                 senp_shift = SRCONFIG_SENPENABLE_V2_SHIFT;
 496         } else {
 497                 dev_err(&sr->pdev->dev, "%s: Trying to Configure smartreflex"
 498                         "module without specifying the ip\n", __func__);
 499                 return -EINVAL;
 500         }
 501
 502         sr_config |= ((senn_en << senn_shift) | (senp_en << senp_shift));
 503         sr_write_reg(sr, SRCONFIG, sr_config);
 504         sr_avgwt = (sr->senp_avgweight << AVGWEIGHT_SENPAVGWEIGHT_SHIFT) |
 505                 (sr->senn_avgweight << AVGWEIGHT_SENNAVGWEIGHT_SHIFT);
 506         sr_write_reg(sr, AVGWEIGHT, sr_avgwt);
 507
 508         /*
 509          * Enabling the interrupts if MINMAXAVG module is used.
 510          * TODO: check if all the interrupts are mandatory
 511          */
 512         if (sr->ip_type == SR_TYPE_V1) {
 513                 sr_modify_reg(sr, ERRCONFIG_V1,
 514                         (ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUVALIDINTEN |
 515                         ERRCONFIG_MCUBOUNDINTEN),
 516                         (ERRCONFIG_MCUACCUMINTEN | ERRCONFIG_MCUACCUMINTST |
 517                          ERRCONFIG_MCUVALIDINTEN | ERRCONFIG_MCUVALIDINTST |
 518                          ERRCONFIG_MCUBOUNDINTEN | ERRCONFIG_MCUBOUNDINTST));
 519         } else if (sr->ip_type == SR_TYPE_V2) {
 520                 sr_write_reg(sr, IRQSTATUS,
 521                         IRQSTATUS_MCUACCUMINT | IRQSTATUS_MCVALIDINT |
 522                         IRQSTATUS_MCBOUNDSINT | IRQSTATUS_MCUDISABLEACKINT);
 523                 sr_write_reg(sr, IRQENABLE_SET,
 524                         IRQENABLE_MCUACCUMINT | IRQENABLE_MCUVALIDINT |
 525                         IRQENABLE_MCUBOUNDSINT | IRQENABLE_MCUDISABLEACKINT);
 526         }
 527
 528         return 0;
 529 }
 530
 531 /**
 532  * sr_enable() - Enables the smartreflex module.
 533  * @voltdm:     VDD pointer to which the SR module to be configured belongs to.
 534  * @volt:       The voltage at which the Voltage domain associated with
 535  *              the smartreflex module is operating at.
 536  *              This is required only to program the correct Ntarget value.
 537  *
 538  * This API is to be called from the smartreflex class driver to
 539  * enable a smartreflex module. Returns 0 on success. Returns error
 540  * value if the voltage passed is wrong or if ntarget value is wrong.
 541  */
 542 int sr_enable(struct voltagedomain *voltdm, unsigned long volt)
 543 {
 544         u32 nvalue_reciprocal;
 545         struct omap_volt_data *volt_data;
 546         struct omap_sr *sr = _sr_lookup(voltdm);
 547         int ret;
 548
 549         if (IS_ERR(sr)) {
 550                 pr_warning("%s: omap_sr struct for sr_%s not found\n",
 551                         __func__, voltdm->name);
 552                 return -EINVAL;
 553         }
 554
 555         volt_data = omap_voltage_get_voltdata(sr->voltdm, volt);
 556
 557         if (IS_ERR(volt_data)) {
 558                 dev_warn(&sr->pdev->dev, "%s: Unable to get voltage table"
 559                         "for nominal voltage %ld\n", __func__, volt);
 560                 return -ENODATA;
 561         }
 562
 563         nvalue_reciprocal = sr_retrieve_nvalue(sr, volt_data->sr_efuse_offs);
 564
 565         if (!nvalue_reciprocal) {
 566                 dev_warn(&sr->pdev->dev, "%s: NVALUE = 0 at voltage %ld\n",
 567                         __func__, volt);
 568                 return -ENODATA;
 569         }
 570
 571         /* errminlimit is opp dependent and hence linked to voltage */
 572         sr->err_minlimit = volt_data->sr_errminlimit;
 573
 574         pm_runtime_get_sync(&sr->pdev->dev);
 575
 576         /* Check if SR is already enabled. If yes do nothing */
 577         if (sr_read_reg(sr, SRCONFIG) & SRCONFIG_SRENABLE)
 578                 return 0;
 579
 580         /* Configure SR */
 581         ret = sr_class->configure(voltdm);
 582         if (ret)
 583                 return ret;
 584
 585         sr_write_reg(sr, NVALUERECIPROCAL, nvalue_reciprocal);
 586
 587         /* SRCONFIG - enable SR */
 588         sr_modify_reg(sr, SRCONFIG, SRCONFIG_SRENABLE, SRCONFIG_SRENABLE);
 589         return 0;
 590 }
 591
 592 /**
 593  * sr_disable() - Disables the smartreflex module.
 594  * @voltdm:     VDD pointer to which the SR module to be configured belongs to.
 595  *
 596  * This API is to be called from the smartreflex class driver to
 597  * disable a smartreflex module.
 598  */
 599 void sr_disable(struct voltagedomain *voltdm)
 600 {
 601         struct omap_sr *sr = _sr_lookup(voltdm);
 602
 603         if (IS_ERR(sr)) {
 604                 pr_warning("%s: omap_sr struct for sr_%s not found\n",
 605                         __func__, voltdm->name);
 606                 return;
 607         }
 608
 609         /* Check if SR clocks are already disabled. If yes do nothing */
 610         if (pm_runtime_suspended(&sr->pdev->dev))
 611                 return;
 612
 613         /*
 614          * Disable SR if only it is indeed enabled. Else just
 615          * disable the clocks.
 616          */
 617         if (sr_read_reg(sr, SRCONFIG) & SRCONFIG_SRENABLE) {
 618                 if (sr->ip_type == SR_TYPE_V1)
 619                         sr_v1_disable(sr);
 620                 else if (sr->ip_type == SR_TYPE_V2)
 621                         sr_v2_disable(sr);
 622         }
 623
 624         pm_runtime_put_sync_suspend(&sr->pdev->dev);
 625 }
 626
 627 /**
 628  * sr_register_class() - API to register a smartreflex class parameters.
 629  * @class_data: The structure containing various sr class specific data.
 630  *
 631  * This API is to be called by the smartreflex class driver to register itself
 632  * with the smartreflex driver during init. Returns 0 on success else the
 633  * error value.
 634  */
 635 int sr_register_class(struct omap_sr_class_data *class_data)
 636 {
 637         struct omap_sr *sr_info;
 638
 639         if (!class_data) {
 640                 pr_warning("%s:, Smartreflex class data passed is NULL\n",
 641                         __func__);
 642                 return -EINVAL;
 643         }
 644
 645         if (sr_class) {
 646                 pr_warning("%s: Smartreflex class driver already registered\n",
 647                         __func__);
 648                 return -EBUSY;
 649         }
 650
 651         sr_class = class_data;
 652
 653         /*
 654          * Call into late init to do intializations that require
 655          * both sr driver and sr class driver to be initiallized.
 656          */
 657         list_for_each_entry(sr_info, &sr_list, node)
 658                 sr_late_init(sr_info);
 659
 660         return 0;
 661 }
 662
 663 /**
 664  * omap_sr_enable() -  API to enable SR clocks and to call into the
 665  *                      registered smartreflex class enable API.
 666  * @voltdm:     VDD pointer to which the SR module to be configured belongs to.
 667  *
 668  * This API is to be called from the kernel in order to enable
 669  * a particular smartreflex module. This API will do the initial
 670  * configurations to turn on the smartreflex module and in turn call
 671  * into the registered smartreflex class enable API.
 672  */
 673 void omap_sr_enable(struct voltagedomain *voltdm)
 674 {
 675         struct omap_sr *sr = _sr_lookup(voltdm);
 676
 677         if (IS_ERR(sr)) {
 678                 pr_warning("%s: omap_sr struct for sr_%s not found\n",
 679                         __func__, voltdm->name);
 680                 return;
 681         }
 682
 683         if (!sr->autocomp_active)
 684                 return;
 685
 686         if (!sr_class || !(sr_class->enable) || !(sr_class->configure)) {
 687                 dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not"
 688                         "registered\n", __func__);
 689                 return;
 690         }
 691
 692         sr_class->enable(voltdm);
 693 }
 694
 695 /**
 696  * omap_sr_disable() - API to disable SR without resetting the voltage
 697  *                      processor voltage
 698  * @voltdm:     VDD pointer to which the SR module to be configured belongs to.
 699  *
 700  * This API is to be called from the kernel in order to disable
 701  * a particular smartreflex module. This API will in turn call
 702  * into the registered smartreflex class disable API. This API will tell
 703  * the smartreflex class disable not to reset the VP voltage after
 704  * disabling smartreflex.
 705  */
 706 void omap_sr_disable(struct voltagedomain *voltdm)
 707 {
 708         struct omap_sr *sr = _sr_lookup(voltdm);
 709
 710         if (IS_ERR(sr)) {
 711                 pr_warning("%s: omap_sr struct for sr_%s not found\n",
 712                         __func__, voltdm->name);
 713                 return;
 714         }
 715
 716         if (!sr->autocomp_active)
 717                 return;
 718
 719         if (!sr_class || !(sr_class->disable)) {
 720                 dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not"
 721                         "registered\n", __func__);
 722                 return;
 723         }
 724
 725         sr_class->disable(voltdm, 0);
 726 }
 727
 728 /**
 729  * omap_sr_disable_reset_volt() - API to disable SR and reset the
 730  *                              voltage processor voltage
 731  * @voltdm:     VDD pointer to which the SR module to be configured belongs to.
 732  *
 733  * This API is to be called from the kernel in order to disable
 734  * a particular smartreflex module. This API will in turn call
 735  * into the registered smartreflex class disable API. This API will tell
 736  * the smartreflex class disable to reset the VP voltage after
 737  * disabling smartreflex.
 738  */
 739 void omap_sr_disable_reset_volt(struct voltagedomain *voltdm)
 740 {
 741         struct omap_sr *sr = _sr_lookup(voltdm);
 742
 743         if (IS_ERR(sr)) {
 744                 pr_warning("%s: omap_sr struct for sr_%s not found\n",
 745                         __func__, voltdm->name);
 746                 return;
 747         }
 748
 749         if (!sr->autocomp_active)
 750                 return;
 751
 752         if (!sr_class || !(sr_class->disable)) {
 753                 dev_warn(&sr->pdev->dev, "%s: smartreflex class driver not"
 754                         "registered\n", __func__);
 755                 return;
 756         }
 757
 758         sr_class->disable(voltdm, 1);
 759 }
 760
 761 /**
 762  * omap_sr_register_pmic() - API to register pmic specific info.
 763  * @pmic_data:  The structure containing pmic specific data.
 764  *
 765  * This API is to be called from the PMIC specific code to register with
 766  * smartreflex driver pmic specific info. Currently the only info required
 767  * is the smartreflex init on the PMIC side.
 768  */
 769 void omap_sr_register_pmic(struct omap_sr_pmic_data *pmic_data)
 770 {
 771         if (!pmic_data) {
 772                 pr_warning("%s: Trying to register NULL PMIC data structure"
 773                         "with smartreflex\n", __func__);
 774                 return;
 775         }
 776
 777         sr_pmic_data = pmic_data;
 778 }
 779
 780 /* PM Debug Fs enteries to enable disable smartreflex. */
 781 static int omap_sr_autocomp_show(void *data, u64 *val)
 782 {
 783         struct omap_sr *sr_info = (struct omap_sr *) data;
 784
 785         if (!sr_info) {
 786                 pr_warning("%s: omap_sr struct not found\n", __func__);
 787                 return -EINVAL;
 788         }
 789
 790         *val = sr_info->autocomp_active;
 791
 792         return 0;
 793 }
 794
 795 static int omap_sr_autocomp_store(void *data, u64 val)
 796 {
 797         struct omap_sr *sr_info = (struct omap_sr *) data;
 798
 799         if (!sr_info) {
 800                 pr_warning("%s: omap_sr struct not found\n", __func__);
 801                 return -EINVAL;
 802         }
 803
 804         /* Sanity check */
 805         if (val && (val != 1)) {
 806                 pr_warning("%s: Invalid argument %lld\n", __func__, val);
 807                 return -EINVAL;
 808         }
 809
 810         /* control enable/disable only if there is a delta in value */
 811         if (sr_info->autocomp_active != val) {
 812                 if (!val)
 813                         sr_stop_vddautocomp(sr_info);
 814                 else
 815                         sr_start_vddautocomp(sr_info);
 816         }
 817
 818         return 0;
 819 }
 820
 821 DEFINE_SIMPLE_ATTRIBUTE(pm_sr_fops, omap_sr_autocomp_show,
 822                 omap_sr_autocomp_store, "%llu\n");
 823
 824 static int __init omap_sr_probe(struct platform_device *pdev)
 825 {
 826         struct omap_sr *sr_info = kzalloc(sizeof(struct omap_sr), GFP_KERNEL);
 827         struct omap_sr_data *pdata = pdev->dev.platform_data;
 828         struct resource *mem, *irq;
 829         struct dentry *vdd_dbg_dir, *nvalue_dir;
 830         struct omap_volt_data *volt_data;
 831         int i, ret = 0;
 832
 833         if (!sr_info) {
 834                 dev_err(&pdev->dev, "%s: unable to allocate sr_info\n",
 835                         __func__);
 836                 return -ENOMEM;
 837         }
 838
 839         if (!pdata) {
 840                 dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
 841                 ret = -EINVAL;
 842                 goto err_free_devinfo;
 843         }
 844
 845         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 846         if (!mem) {
 847                 dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
 848                 ret = -ENODEV;
 849                 goto err_free_devinfo;
 850         }
 851
 852         mem = request_mem_region(mem->start, resource_size(mem),
 853                                         dev_name(&pdev->dev));
 854         if (!mem) {
 855                 dev_err(&pdev->dev, "%s: no mem region\n", __func__);
 856                 ret = -EBUSY;
 857                 goto err_free_devinfo;
 858         }
 859
 860         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 861
 862         pm_runtime_enable(&pdev->dev);
 863         pm_runtime_irq_safe(&pdev->dev);
 864
 865         sr_info->pdev = pdev;
 866         sr_info->srid = pdev->id;
 867         sr_info->voltdm = pdata->voltdm;
 868         sr_info->nvalue_table = pdata->nvalue_table;
 869         sr_info->nvalue_count = pdata->nvalue_count;
 870         sr_info->senn_mod = pdata->senn_mod;
 871         sr_info->senp_mod = pdata->senp_mod;
 872         sr_info->autocomp_active = false;
 873         sr_info->ip_type = pdata->ip_type;
 874         sr_info->base = ioremap(mem->start, resource_size(mem));
 875         if (!sr_info->base) {
 876                 dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
 877                 ret = -ENOMEM;
 878                 goto err_release_region;
 879         }
 880
 881         if (irq)
 882                 sr_info->irq = irq->start;
 883
 884         sr_set_clk_length(sr_info);
 885         sr_set_regfields(sr_info);
 886
 887         list_add(&sr_info->node, &sr_list);
 888
 889         /*
 890          * Call into late init to do intializations that require
 891          * both sr driver and sr class driver to be initiallized.
 892          */
 893         if (sr_class) {
 894                 ret = sr_late_init(sr_info);
 895                 if (ret) {
 896                         pr_warning("%s: Error in SR late init\n", __func__);
 897                         return ret;
 898                 }
 899         }
 900
 901         dev_info(&pdev->dev, "%s: SmartReflex driver initialized\n", __func__);
 902
 903         /*
 904          * If the voltage domain debugfs directory is not created, do
 905          * not try to create rest of the debugfs entries.
 906          */
 907         vdd_dbg_dir = omap_voltage_get_dbgdir(sr_info->voltdm);
 908         if (!vdd_dbg_dir) {
 909                 ret = -EINVAL;
 910                 goto err_iounmap;
 911         }
 912
 913         sr_info->dbg_dir = debugfs_create_dir("smartreflex", vdd_dbg_dir);
 914         if (IS_ERR(sr_info->dbg_dir)) {
 915                 dev_err(&pdev->dev, "%s: Unable to create debugfs directory\n",
 916                         __func__);
 917                 ret = PTR_ERR(sr_info->dbg_dir);
 918                 goto err_iounmap;
 919         }
 920
 921         (void) debugfs_create_file("autocomp", S_IRUGO | S_IWUSR,
 922                         sr_info->dbg_dir, (void *)sr_info, &pm_sr_fops);
 923         (void) debugfs_create_x32("errweight", S_IRUGO, sr_info->dbg_dir,
 924                         &sr_info->err_weight);
 925         (void) debugfs_create_x32("errmaxlimit", S_IRUGO, sr_info->dbg_dir,
 926                         &sr_info->err_maxlimit);
 927         (void) debugfs_create_x32("errminlimit", S_IRUGO, sr_info->dbg_dir,
 928                         &sr_info->err_minlimit);
 929
 930         nvalue_dir = debugfs_create_dir("nvalue", sr_info->dbg_dir);
 931         if (IS_ERR(nvalue_dir)) {
 932                 dev_err(&pdev->dev, "%s: Unable to create debugfs directory"
 933                         "for n-values\n", __func__);
 934                 ret = PTR_ERR(nvalue_dir);
 935                 goto err_debugfs;
 936         }
 937
 938         omap_voltage_get_volttable(sr_info->voltdm, &volt_data);
 939         if (!volt_data) {
 940                 dev_warn(&pdev->dev, "%s: No Voltage table for the"
 941                         " corresponding vdd vdd_%s. Cannot create debugfs"
 942                         "entries for n-values\n",
 943                         __func__, sr_info->voltdm->name);
 944                 ret = -ENODATA;
 945                 goto err_debugfs;
 946         }
 947
 948         for (i = 0; i < sr_info->nvalue_count; i++) {
 949                 char name[NVALUE_NAME_LEN + 1];
 950
 951                 snprintf(name, sizeof(name), "volt_%d",
 952                          volt_data[i].volt_nominal);
 953                 (void) debugfs_create_x32(name, S_IRUGO | S_IWUSR, nvalue_dir,
 954                                 &(sr_info->nvalue_table[i].nvalue));
 955         }
 956
 957         return ret;
 958
 959 err_debugfs:
 960         debugfs_remove_recursive(sr_info->dbg_dir);
 961 err_iounmap:
 962         list_del(&sr_info->node);
 963         iounmap(sr_info->base);
 964 err_release_region:
 965         release_mem_region(mem->start, resource_size(mem));
 966 err_free_devinfo:
 967         kfree(sr_info);
 968
 969         return ret;
 970 }
 971
 972 static int __devexit omap_sr_remove(struct platform_device *pdev)
 973 {
 974         struct omap_sr_data *pdata = pdev->dev.platform_data;
 975         struct omap_sr *sr_info;
 976         struct resource *mem;
 977
 978         if (!pdata) {
 979                 dev_err(&pdev->dev, "%s: platform data missing\n", __func__);
 980                 return -EINVAL;
 981         }
 982
 983         sr_info = _sr_lookup(pdata->voltdm);
 984         if (IS_ERR(sr_info)) {
 985                 dev_warn(&pdev->dev, "%s: omap_sr struct not found\n",
 986                         __func__);
 987                 return -EINVAL;
 988         }
 989
 990         if (sr_info->autocomp_active)
 991                 sr_stop_vddautocomp(sr_info);
 992         if (sr_info->dbg_dir)
 993                 debugfs_remove_recursive(sr_info->dbg_dir);
 994
 995         list_del(&sr_info->node);
 996         iounmap(sr_info->base);
 997         kfree(sr_info);
 998         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 999         release_mem_region(mem->start, resource_size(mem));
1000
1001         return 0;
1002 }
1003
1004 static struct platform_driver smartreflex_driver = {
1005         .remove         = omap_sr_remove,
1006         .driver         = {
1007                 .name   = "smartreflex",
1008         },
1009 };
1010
1011 static int __init sr_init(void)
1012 {
1013         int ret = 0;
1014
1015         /*
1016          * sr_init is a late init. If by then a pmic specific API is not
1017          * registered either there is no need for anything to be done on
1018          * the PMIC side or somebody has forgotten to register a PMIC
1019          * handler. Warn for the second condition.
1020          */
1021         if (sr_pmic_data && sr_pmic_data->sr_pmic_init)
1022                 sr_pmic_data->sr_pmic_init();
1023         else
1024                 pr_warning("%s: No PMIC hook to init smartreflex\n", __func__);
1025
1026         ret = platform_driver_probe(&smartreflex_driver, omap_sr_probe);
1027         if (ret) {
1028                 pr_err("%s: platform driver register failed for SR\n",
1029                         __func__);
1030                 return ret;
1031         }
1032
1033         return 0;
1034 }
1035
1036 static void __exit sr_exit(void)
1037 {
1038         platform_driver_unregister(&smartreflex_driver);
1039 }
1040 late_initcall(sr_init);
1041 module_exit(sr_exit);
1042
1043 MODULE_DESCRIPTION("OMAP Smartreflex Driver");
1044 MODULE_LICENSE("GPL");
1045 MODULE_ALIAS("platform:" DRIVER_NAME);
1046 MODULE_AUTHOR("Texas Instruments Inc");