drivers/mfd/wm831x-irq.c

   1 /*
   2  * wm831x-irq.c  --  Interrupt controller support for Wolfson WM831x PMICs
   3  *
   4  * Copyright 2009 Wolfson Microelectronics PLC.
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/i2c.h>
  18 #include <linux/mfd/core.h>
  19 #include <linux/interrupt.h>
  20
  21 #include <linux/mfd/wm831x/core.h>
  22 #include <linux/mfd/wm831x/pdata.h>
  23 #include <linux/mfd/wm831x/irq.h>
  24
  25 #include <linux/delay.h>
  26
  27 /*
  28  * Since generic IRQs don't currently support interrupt controllers on
  29  * interrupt driven buses we don't use genirq but instead provide an
  30  * interface that looks very much like the standard ones.  This leads
  31  * to some bodges, including storing interrupt handler information in
  32  * the static irq_data table we use to look up the data for individual
  33  * interrupts, but hopefully won't last too long.
  34  */
  35
  36 struct wm831x_irq_data {
  37         int primary;
  38         int reg;
  39         int mask;
  40         irq_handler_t handler;
  41         void *handler_data;
  42 };
  43
  44 static struct wm831x_irq_data wm831x_irqs[] = {
  45         [WM831X_IRQ_TEMP_THW] = {
  46                 .primary = WM831X_TEMP_INT,
  47                 .reg = 1,
  48                 .mask = WM831X_TEMP_THW_EINT,
  49         },
  50         [WM831X_IRQ_GPIO_1] = {
  51                 .primary = WM831X_GP_INT,
  52                 .reg = 5,
  53                 .mask = WM831X_GP1_EINT,
  54         },
  55         [WM831X_IRQ_GPIO_2] = {
  56                 .primary = WM831X_GP_INT,
  57                 .reg = 5,
  58                 .mask = WM831X_GP2_EINT,
  59         },
  60         [WM831X_IRQ_GPIO_3] = {
  61                 .primary = WM831X_GP_INT,
  62                 .reg = 5,
  63                 .mask = WM831X_GP3_EINT,
  64         },
  65         [WM831X_IRQ_GPIO_4] = {
  66                 .primary = WM831X_GP_INT,
  67                 .reg = 5,
  68                 .mask = WM831X_GP4_EINT,
  69         },
  70         [WM831X_IRQ_GPIO_5] = {
  71                 .primary = WM831X_GP_INT,
  72                 .reg = 5,
  73                 .mask = WM831X_GP5_EINT,
  74         },
  75         [WM831X_IRQ_GPIO_6] = {
  76                 .primary = WM831X_GP_INT,
  77                 .reg = 5,
  78                 .mask = WM831X_GP6_EINT,
  79         },
  80         [WM831X_IRQ_GPIO_7] = {
  81                 .primary = WM831X_GP_INT,
  82                 .reg = 5,
  83                 .mask = WM831X_GP7_EINT,
  84         },
  85         [WM831X_IRQ_GPIO_8] = {
  86                 .primary = WM831X_GP_INT,
  87                 .reg = 5,
  88                 .mask = WM831X_GP8_EINT,
  89         },
  90         [WM831X_IRQ_GPIO_9] = {
  91                 .primary = WM831X_GP_INT,
  92                 .reg = 5,
  93                 .mask = WM831X_GP9_EINT,
  94         },
  95         [WM831X_IRQ_GPIO_10] = {
  96                 .primary = WM831X_GP_INT,
  97                 .reg = 5,
  98                 .mask = WM831X_GP10_EINT,
  99         },
 100         [WM831X_IRQ_GPIO_11] = {
 101                 .primary = WM831X_GP_INT,
 102                 .reg = 5,
 103                 .mask = WM831X_GP11_EINT,
 104         },
 105         [WM831X_IRQ_GPIO_12] = {
 106                 .primary = WM831X_GP_INT,
 107                 .reg = 5,
 108                 .mask = WM831X_GP12_EINT,
 109         },
 110         [WM831X_IRQ_GPIO_13] = {
 111                 .primary = WM831X_GP_INT,
 112                 .reg = 5,
 113                 .mask = WM831X_GP13_EINT,
 114         },
 115         [WM831X_IRQ_GPIO_14] = {
 116                 .primary = WM831X_GP_INT,
 117                 .reg = 5,
 118                 .mask = WM831X_GP14_EINT,
 119         },
 120         [WM831X_IRQ_GPIO_15] = {
 121                 .primary = WM831X_GP_INT,
 122                 .reg = 5,
 123                 .mask = WM831X_GP15_EINT,
 124         },
 125         [WM831X_IRQ_GPIO_16] = {
 126                 .primary = WM831X_GP_INT,
 127                 .reg = 5,
 128                 .mask = WM831X_GP16_EINT,
 129         },
 130         [WM831X_IRQ_ON] = {
 131                 .primary = WM831X_ON_PIN_INT,
 132                 .reg = 1,
 133                 .mask = WM831X_ON_PIN_EINT,
 134         },
 135         [WM831X_IRQ_PPM_SYSLO] = {
 136                 .primary = WM831X_PPM_INT,
 137                 .reg = 1,
 138                 .mask = WM831X_PPM_SYSLO_EINT,
 139         },
 140         [WM831X_IRQ_PPM_PWR_SRC] = {
 141                 .primary = WM831X_PPM_INT,
 142                 .reg = 1,
 143                 .mask = WM831X_PPM_PWR_SRC_EINT,
 144         },
 145         [WM831X_IRQ_PPM_USB_CURR] = {
 146                 .primary = WM831X_PPM_INT,
 147                 .reg = 1,
 148                 .mask = WM831X_PPM_USB_CURR_EINT,
 149         },
 150         [WM831X_IRQ_WDOG_TO] = {
 151                 .primary = WM831X_WDOG_INT,
 152                 .reg = 1,
 153                 .mask = WM831X_WDOG_TO_EINT,
 154         },
 155         [WM831X_IRQ_RTC_PER] = {
 156                 .primary = WM831X_RTC_INT,
 157                 .reg = 1,
 158                 .mask = WM831X_RTC_PER_EINT,
 159         },
 160         [WM831X_IRQ_RTC_ALM] = {
 161                 .primary = WM831X_RTC_INT,
 162                 .reg = 1,
 163                 .mask = WM831X_RTC_ALM_EINT,
 164         },
 165         [WM831X_IRQ_CHG_BATT_HOT] = {
 166                 .primary = WM831X_CHG_INT,
 167                 .reg = 2,
 168                 .mask = WM831X_CHG_BATT_HOT_EINT,
 169         },
 170         [WM831X_IRQ_CHG_BATT_COLD] = {
 171                 .primary = WM831X_CHG_INT,
 172                 .reg = 2,
 173                 .mask = WM831X_CHG_BATT_COLD_EINT,
 174         },
 175         [WM831X_IRQ_CHG_BATT_FAIL] = {
 176                 .primary = WM831X_CHG_INT,
 177                 .reg = 2,
 178                 .mask = WM831X_CHG_BATT_FAIL_EINT,
 179         },
 180         [WM831X_IRQ_CHG_OV] = {
 181                 .primary = WM831X_CHG_INT,
 182                 .reg = 2,
 183                 .mask = WM831X_CHG_OV_EINT,
 184         },
 185         [WM831X_IRQ_CHG_END] = {
 186                 .primary = WM831X_CHG_INT,
 187                 .reg = 2,
 188                 .mask = WM831X_CHG_END_EINT,
 189         },
 190         [WM831X_IRQ_CHG_TO] = {
 191                 .primary = WM831X_CHG_INT,
 192                 .reg = 2,
 193                 .mask = WM831X_CHG_TO_EINT,
 194         },
 195         [WM831X_IRQ_CHG_MODE] = {
 196                 .primary = WM831X_CHG_INT,
 197                 .reg = 2,
 198                 .mask = WM831X_CHG_MODE_EINT,
 199         },
 200         [WM831X_IRQ_CHG_START] = {
 201                 .primary = WM831X_CHG_INT,
 202                 .reg = 2,
 203                 .mask = WM831X_CHG_START_EINT,
 204         },
 205         [WM831X_IRQ_TCHDATA] = {
 206                 .primary = WM831X_TCHDATA_INT,
 207                 .reg = 1,
 208                 .mask = WM831X_TCHDATA_EINT,
 209         },
 210         [WM831X_IRQ_TCHPD] = {
 211                 .primary = WM831X_TCHPD_INT,
 212                 .reg = 1,
 213                 .mask = WM831X_TCHPD_EINT,
 214         },
 215         [WM831X_IRQ_AUXADC_DATA] = {
 216                 .primary = WM831X_AUXADC_INT,
 217                 .reg = 1,
 218                 .mask = WM831X_AUXADC_DATA_EINT,
 219         },
 220         [WM831X_IRQ_AUXADC_DCOMP1] = {
 221                 .primary = WM831X_AUXADC_INT,
 222                 .reg = 1,
 223                 .mask = WM831X_AUXADC_DCOMP1_EINT,
 224         },
 225         [WM831X_IRQ_AUXADC_DCOMP2] = {
 226                 .primary = WM831X_AUXADC_INT,
 227                 .reg = 1,
 228                 .mask = WM831X_AUXADC_DCOMP2_EINT,
 229         },
 230         [WM831X_IRQ_AUXADC_DCOMP3] = {
 231                 .primary = WM831X_AUXADC_INT,
 232                 .reg = 1,
 233                 .mask = WM831X_AUXADC_DCOMP3_EINT,
 234         },
 235         [WM831X_IRQ_AUXADC_DCOMP4] = {
 236                 .primary = WM831X_AUXADC_INT,
 237                 .reg = 1,
 238                 .mask = WM831X_AUXADC_DCOMP4_EINT,
 239         },
 240         [WM831X_IRQ_CS1] = {
 241                 .primary = WM831X_CS_INT,
 242                 .reg = 2,
 243                 .mask = WM831X_CS1_EINT,
 244         },
 245         [WM831X_IRQ_CS2] = {
 246                 .primary = WM831X_CS_INT,
 247                 .reg = 2,
 248                 .mask = WM831X_CS2_EINT,
 249         },
 250         [WM831X_IRQ_HC_DC1] = {
 251                 .primary = WM831X_HC_INT,
 252                 .reg = 4,
 253                 .mask = WM831X_HC_DC1_EINT,
 254         },
 255         [WM831X_IRQ_HC_DC2] = {
 256                 .primary = WM831X_HC_INT,
 257                 .reg = 4,
 258                 .mask = WM831X_HC_DC2_EINT,
 259         },
 260         [WM831X_IRQ_UV_LDO1] = {
 261                 .primary = WM831X_UV_INT,
 262                 .reg = 3,
 263                 .mask = WM831X_UV_LDO1_EINT,
 264         },
 265         [WM831X_IRQ_UV_LDO2] = {
 266                 .primary = WM831X_UV_INT,
 267                 .reg = 3,
 268                 .mask = WM831X_UV_LDO2_EINT,
 269         },
 270         [WM831X_IRQ_UV_LDO3] = {
 271                 .primary = WM831X_UV_INT,
 272                 .reg = 3,
 273                 .mask = WM831X_UV_LDO3_EINT,
 274         },
 275         [WM831X_IRQ_UV_LDO4] = {
 276                 .primary = WM831X_UV_INT,
 277                 .reg = 3,
 278                 .mask = WM831X_UV_LDO4_EINT,
 279         },
 280         [WM831X_IRQ_UV_LDO5] = {
 281                 .primary = WM831X_UV_INT,
 282                 .reg = 3,
 283                 .mask = WM831X_UV_LDO5_EINT,
 284         },
 285         [WM831X_IRQ_UV_LDO6] = {
 286                 .primary = WM831X_UV_INT,
 287                 .reg = 3,
 288                 .mask = WM831X_UV_LDO6_EINT,
 289         },
 290         [WM831X_IRQ_UV_LDO7] = {
 291                 .primary = WM831X_UV_INT,
 292                 .reg = 3,
 293                 .mask = WM831X_UV_LDO7_EINT,
 294         },
 295         [WM831X_IRQ_UV_LDO8] = {
 296                 .primary = WM831X_UV_INT,
 297                 .reg = 3,
 298                 .mask = WM831X_UV_LDO8_EINT,
 299         },
 300         [WM831X_IRQ_UV_LDO9] = {
 301                 .primary = WM831X_UV_INT,
 302                 .reg = 3,
 303                 .mask = WM831X_UV_LDO9_EINT,
 304         },
 305         [WM831X_IRQ_UV_LDO10] = {
 306                 .primary = WM831X_UV_INT,
 307                 .reg = 3,
 308                 .mask = WM831X_UV_LDO10_EINT,
 309         },
 310         [WM831X_IRQ_UV_DC1] = {
 311                 .primary = WM831X_UV_INT,
 312                 .reg = 4,
 313                 .mask = WM831X_UV_DC1_EINT,
 314         },
 315         [WM831X_IRQ_UV_DC2] = {
 316                 .primary = WM831X_UV_INT,
 317                 .reg = 4,
 318                 .mask = WM831X_UV_DC2_EINT,
 319         },
 320         [WM831X_IRQ_UV_DC3] = {
 321                 .primary = WM831X_UV_INT,
 322                 .reg = 4,
 323                 .mask = WM831X_UV_DC3_EINT,
 324         },
 325         [WM831X_IRQ_UV_DC4] = {
 326                 .primary = WM831X_UV_INT,
 327                 .reg = 4,
 328                 .mask = WM831X_UV_DC4_EINT,
 329         },
 330 };
 331
 332 static inline int irq_data_to_status_reg(struct wm831x_irq_data *irq_data)
 333 {
 334         return WM831X_INTERRUPT_STATUS_1 - 1 + irq_data->reg;
 335 }
 336
 337 static inline int irq_data_to_mask_reg(struct wm831x_irq_data *irq_data)
 338 {
 339         return WM831X_INTERRUPT_STATUS_1_MASK - 1 + irq_data->reg;
 340 }
 341
 342 static void __wm831x_enable_irq(struct wm831x *wm831x, int irq)
 343 {
 344         struct wm831x_irq_data *irq_data = &wm831x_irqs[irq];
 345
 346         wm831x->irq_masks[irq_data->reg - 1] &= ~irq_data->mask;
 347         wm831x_reg_write(wm831x, irq_data_to_mask_reg(irq_data),
 348                          wm831x->irq_masks[irq_data->reg - 1]);
 349 }
 350
 351 void wm831x_enable_irq(struct wm831x *wm831x, int irq)
 352 {
 353         mutex_lock(&wm831x->irq_lock);
 354         __wm831x_enable_irq(wm831x, irq);
 355         mutex_unlock(&wm831x->irq_lock);
 356 }
 357 EXPORT_SYMBOL_GPL(wm831x_enable_irq);
 358
 359 static void __wm831x_disable_irq(struct wm831x *wm831x, int irq)
 360 {
 361         struct wm831x_irq_data *irq_data = &wm831x_irqs[irq];
 362
 363         wm831x->irq_masks[irq_data->reg - 1] |= irq_data->mask;
 364         wm831x_reg_write(wm831x, irq_data_to_mask_reg(irq_data),
 365                          wm831x->irq_masks[irq_data->reg - 1]);
 366 }
 367
 368 void wm831x_disable_irq(struct wm831x *wm831x, int irq)
 369 {
 370         mutex_lock(&wm831x->irq_lock);
 371         __wm831x_disable_irq(wm831x, irq);
 372         mutex_unlock(&wm831x->irq_lock);
 373 }
 374 EXPORT_SYMBOL_GPL(wm831x_disable_irq);
 375
 376 int wm831x_request_irq(struct wm831x *wm831x,
 377                        unsigned int irq, irq_handler_t handler,
 378                        unsigned long flags, const char *name,
 379                        void *dev)
 380 {
 381         int ret = 0;
 382
 383         if (irq < 0 || irq >= WM831X_NUM_IRQS)
 384                 return -EINVAL;
 385
 386         mutex_lock(&wm831x->irq_lock);
 387
 388         if (wm831x_irqs[irq].handler) {
 389                 dev_err(wm831x->dev, "Already have handler for IRQ %d\n", irq);
 390                 ret = -EINVAL;
 391                 goto out;
 392         }
 393
 394         wm831x_irqs[irq].handler = handler;
 395         wm831x_irqs[irq].handler_data = dev;
 396
 397         __wm831x_enable_irq(wm831x, irq);
 398
 399 out:
 400         mutex_unlock(&wm831x->irq_lock);
 401
 402         return ret;
 403 }
 404 EXPORT_SYMBOL_GPL(wm831x_request_irq);
 405
 406 void wm831x_free_irq(struct wm831x *wm831x, unsigned int irq, void *data)
 407 {
 408         if (irq < 0 || irq >= WM831X_NUM_IRQS)
 409                 return;
 410
 411         mutex_lock(&wm831x->irq_lock);
 412
 413         wm831x_irqs[irq].handler = NULL;
 414         wm831x_irqs[irq].handler_data = NULL;
 415
 416         __wm831x_disable_irq(wm831x, irq);
 417
 418         mutex_unlock(&wm831x->irq_lock);
 419 }
 420 EXPORT_SYMBOL_GPL(wm831x_free_irq);
 421
 422
 423 static void wm831x_handle_irq(struct wm831x *wm831x, int irq, int status)
 424 {
 425         struct wm831x_irq_data *irq_data = &wm831x_irqs[irq];
 426
 427         if (irq_data->handler) {
 428                 irq_data->handler(irq, irq_data->handler_data);
 429                 wm831x_reg_write(wm831x, irq_data_to_status_reg(irq_data),
 430                                  irq_data->mask);
 431         } else {
 432                 dev_err(wm831x->dev, "Unhandled IRQ %d, masking\n", irq);
 433                 __wm831x_disable_irq(wm831x, irq);
 434         }
 435 }
 436
 437 /* Main interrupt handling occurs in a workqueue since we need
 438  * interrupts enabled to interact with the chip. */
 439 static void wm831x_irq_worker(struct work_struct *work)
 440 {
 441         struct wm831x *wm831x = container_of(work, struct wm831x, irq_work);
 442         unsigned int i;
 443         int primary;
 444         int status_regs[5];
 445         int read[5] = { 0 };
 446         int *status;
 447
 448         primary = wm831x_reg_read(wm831x, WM831X_SYSTEM_INTERRUPTS);
 449         if (primary < 0) {
 450                 dev_err(wm831x->dev, "Failed to read system interrupt: %d\n",
 451                         primary);
 452                 goto out;
 453         }
 454
 455         mutex_lock(&wm831x->irq_lock);
 456
 457         for (i = 0; i < ARRAY_SIZE(wm831x_irqs); i++) {
 458                 int offset = wm831x_irqs[i].reg - 1;
 459
 460                 if (!(primary & wm831x_irqs[i].primary))
 461                         continue;
 462
 463                 status = &status_regs[offset];
 464
 465                 /* Hopefully there should only be one register to read
 466                  * each time otherwise we ought to do a block read. */
 467                 if (!read[offset]) {
 468                         *status = wm831x_reg_read(wm831x,
 469                                      irq_data_to_status_reg(&wm831x_irqs[i]));
 470                         if (*status < 0) {
 471                                 dev_err(wm831x->dev,
 472                                         "Failed to read IRQ status: %d\n",
 473                                         *status);
 474                                 goto out_lock;
 475                         }
 476
 477                         /* Mask out the disabled IRQs */
 478                         *status &= ~wm831x->irq_masks[offset];
 479                         read[offset] = 1;
 480                 }
 481
 482                 if (*status & wm831x_irqs[i].mask)
 483                         wm831x_handle_irq(wm831x, i, *status);
 484         }
 485
 486 out_lock:
 487         mutex_unlock(&wm831x->irq_lock);
 488 out:
 489         enable_irq(wm831x->irq);
 490 }
 491
 492
 493 static irqreturn_t wm831x_cpu_irq(int irq, void *data)
 494 {
 495         struct wm831x *wm831x = data;
 496
 497         /* Shut the interrupt to the CPU up and schedule the actual
 498          * handler; we can't check that the IRQ is asserted. */
 499         disable_irq_nosync(irq);
 500
 501         queue_work(wm831x->irq_wq, &wm831x->irq_work);
 502
 503         return IRQ_HANDLED;
 504 }
 505
 506 int wm831x_irq_init(struct wm831x *wm831x, int irq)
 507 {
 508         int i, ret;
 509
 510         mutex_init(&wm831x->irq_lock);
 511
 512         if (!irq) {
 513                 dev_warn(wm831x->dev,
 514                          "No interrupt specified - functionality limited\n");
 515                 return 0;
 516         }
 517
 518
 519         wm831x->irq_wq = create_singlethread_workqueue("wm831x-irq");
 520         if (!wm831x->irq_wq) {
 521                 dev_err(wm831x->dev, "Failed to allocate IRQ worker\n");
 522                 return -ESRCH;
 523         }
 524
 525         wm831x->irq = irq;
 526         INIT_WORK(&wm831x->irq_work, wm831x_irq_worker);
 527
 528         /* Mask the individual interrupt sources */
 529         for (i = 0; i < ARRAY_SIZE(wm831x->irq_masks); i++) {
 530                 wm831x->irq_masks[i] = 0xffff;
 531                 wm831x_reg_write(wm831x, WM831X_INTERRUPT_STATUS_1_MASK + i,
 532                                  0xffff);
 533         }
 534
 535         /* Enable top level interrupts, we mask at secondary level */
 536         wm831x_reg_write(wm831x, WM831X_SYSTEM_INTERRUPTS_MASK, 0);
 537
 538         /* We're good to go.  We set IRQF_SHARED since there's a
 539          * chance the driver will interoperate with another driver but
 540          * the need to disable the IRQ while handing via I2C/SPI means
 541          * that this may break and performance will be impacted.  If
 542          * this does happen it's a hardware design issue and the only
 543          * other alternative would be polling.
 544          */
 545         ret = request_irq(irq, wm831x_cpu_irq, IRQF_TRIGGER_LOW | IRQF_SHARED,
 546                           "wm831x", wm831x);
 547         if (ret != 0) {
 548                 dev_err(wm831x->dev, "Failed to request IRQ %d: %d\n",
 549                         irq, ret);
 550                 return ret;
 551         }
 552
 553         return 0;
 554 }
 555
 556 void wm831x_irq_exit(struct wm831x *wm831x)
 557 {
 558         if (wm831x->irq)
 559                 free_irq(wm831x->irq, wm831x);
 560 }