drivers/gpio/gpio-ab8500.c

   1 /*
   2  * Copyright (C) ST-Ericsson SA 2011
   3  *
   4  * Author: BIBEK BASU <bibek.basu@stericsson.com>
   5  * License terms: GNU General Public License (GPL) version 2
   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 version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/types.h>
  13 #include <linux/slab.h>
  14 #include <linux/init.h>
  15 #include <linux/module.h>
  16 #include <linux/err.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/gpio.h>
  19 #include <linux/irq.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/mfd/ab8500.h>
  22 #include <linux/mfd/abx500.h>
  23 #include <linux/mfd/ab8500/gpio.h>
  24
  25 /*
  26  * GPIO registers offset
  27  * Bank: 0x10
  28  */
  29 #define AB8500_GPIO_SEL1_REG    0x00
  30 #define AB8500_GPIO_SEL2_REG    0x01
  31 #define AB8500_GPIO_SEL3_REG    0x02
  32 #define AB8500_GPIO_SEL4_REG    0x03
  33 #define AB8500_GPIO_SEL5_REG    0x04
  34 #define AB8500_GPIO_SEL6_REG    0x05
  35
  36 #define AB8500_GPIO_DIR1_REG    0x10
  37 #define AB8500_GPIO_DIR2_REG    0x11
  38 #define AB8500_GPIO_DIR3_REG    0x12
  39 #define AB8500_GPIO_DIR4_REG    0x13
  40 #define AB8500_GPIO_DIR5_REG    0x14
  41 #define AB8500_GPIO_DIR6_REG    0x15
  42
  43 #define AB8500_GPIO_OUT1_REG    0x20
  44 #define AB8500_GPIO_OUT2_REG    0x21
  45 #define AB8500_GPIO_OUT3_REG    0x22
  46 #define AB8500_GPIO_OUT4_REG    0x23
  47 #define AB8500_GPIO_OUT5_REG    0x24
  48 #define AB8500_GPIO_OUT6_REG    0x25
  49
  50 #define AB8500_GPIO_PUD1_REG    0x30
  51 #define AB8500_GPIO_PUD2_REG    0x31
  52 #define AB8500_GPIO_PUD3_REG    0x32
  53 #define AB8500_GPIO_PUD4_REG    0x33
  54 #define AB8500_GPIO_PUD5_REG    0x34
  55 #define AB8500_GPIO_PUD6_REG    0x35
  56
  57 #define AB8500_GPIO_IN1_REG     0x40
  58 #define AB8500_GPIO_IN2_REG     0x41
  59 #define AB8500_GPIO_IN3_REG     0x42
  60 #define AB8500_GPIO_IN4_REG     0x43
  61 #define AB8500_GPIO_IN5_REG     0x44
  62 #define AB8500_GPIO_IN6_REG     0x45
  63 #define AB8500_GPIO_ALTFUN_REG  0x45
  64 #define ALTFUN_REG_INDEX        6
  65 #define AB8500_NUM_GPIO         42
  66 #define AB8500_NUM_VIR_GPIO_IRQ 16
  67
  68 enum ab8500_gpio_action {
  69         NONE,
  70         STARTUP,
  71         SHUTDOWN,
  72         MASK,
  73         UNMASK
  74 };
  75
  76 struct ab8500_gpio {
  77         struct gpio_chip chip;
  78         struct ab8500 *parent;
  79         struct device *dev;
  80         struct mutex lock;
  81         u32 irq_base;
  82         enum ab8500_gpio_action irq_action;
  83         u16 rising;
  84         u16 falling;
  85 };
  86 /**
  87  * to_ab8500_gpio() - get the pointer to ab8500_gpio
  88  * @chip:       Member of the structure ab8500_gpio
  89  */
  90 static inline struct ab8500_gpio *to_ab8500_gpio(struct gpio_chip *chip)
  91 {
  92         return container_of(chip, struct ab8500_gpio, chip);
  93 }
  94
  95 static int ab8500_gpio_set_bits(struct gpio_chip *chip, u8 reg,
  96                                         unsigned offset, int val)
  97 {
  98         struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip);
  99         u8 pos = offset % 8;
 100         int ret;
 101
 102         reg = reg + (offset / 8);
 103         ret = abx500_mask_and_set_register_interruptible(ab8500_gpio->dev,
 104                                 AB8500_MISC, reg, 1 << pos, val << pos);
 105         if (ret < 0)
 106                 dev_err(ab8500_gpio->dev, "%s write failed\n", __func__);
 107         return ret;
 108 }
 109 /**
 110  * ab8500_gpio_get() - Get the particular GPIO value
 111  * @chip: Gpio device
 112  * @offset: GPIO number to read
 113  */
 114 static int ab8500_gpio_get(struct gpio_chip *chip, unsigned offset)
 115 {
 116         struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip);
 117         u8 mask = 1 << (offset % 8);
 118         u8 reg = AB8500_GPIO_OUT1_REG + (offset / 8);
 119         int ret;
 120         u8 data;
 121         ret = abx500_get_register_interruptible(ab8500_gpio->dev, AB8500_MISC,
 122                                                 reg, &data);
 123         if (ret < 0) {
 124                 dev_err(ab8500_gpio->dev, "%s read failed\n", __func__);
 125                 return ret;
 126         }
 127         return (data & mask) >> (offset % 8);
 128 }
 129
 130 static void ab8500_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
 131 {
 132         struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip);
 133         int ret;
 134         /* Write the data */
 135         ret = ab8500_gpio_set_bits(chip, AB8500_GPIO_OUT1_REG, offset, 1);
 136         if (ret < 0)
 137                 dev_err(ab8500_gpio->dev, "%s write failed\n", __func__);
 138 }
 139
 140 static int ab8500_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 141                                         int val)
 142 {
 143         int ret;
 144         /* set direction as output */
 145         ret = ab8500_gpio_set_bits(chip, AB8500_GPIO_DIR1_REG, offset, 1);
 146         if (ret < 0)
 147                 return ret;
 148         /* disable pull down */
 149         ret = ab8500_gpio_set_bits(chip, AB8500_GPIO_PUD1_REG, offset, 1);
 150         if (ret < 0)
 151                 return ret;
 152         /* set the output as 1 or 0 */
 153         return ab8500_gpio_set_bits(chip, AB8500_GPIO_OUT1_REG, offset, val);
 154
 155 }
 156
 157 static int ab8500_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 158 {
 159         /* set the register as input */
 160         return ab8500_gpio_set_bits(chip, AB8500_GPIO_DIR1_REG, offset, 0);
 161 }
 162
 163 static int ab8500_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 164 {
 165         /*
 166          * Only some GPIOs are interrupt capable, and they are
 167          * organized in discontiguous clusters:
 168          *
 169          *      GPIO6 to GPIO13
 170          *      GPIO24 and GPIO25
 171          *      GPIO36 to GPIO41
 172          */
 173         static struct ab8500_gpio_irq_cluster {
 174                 int start;
 175                 int end;
 176         } clusters[] = {
 177                 {.start = 6,  .end = 13},
 178                 {.start = 24, .end = 25},
 179                 {.start = 36, .end = 41},
 180         };
 181         struct ab8500_gpio *ab8500_gpio = to_ab8500_gpio(chip);
 182         int base = ab8500_gpio->irq_base;
 183         int i;
 184
 185         for (i = 0; i < ARRAY_SIZE(clusters); i++) {
 186                 struct ab8500_gpio_irq_cluster *cluster = &clusters[i];
 187
 188                 if (offset >= cluster->start && offset <= cluster->end)
 189                         return base + offset - cluster->start;
 190
 191                 /* Advance by the number of gpios in this cluster */
 192                 base += cluster->end - cluster->start + 1;
 193         }
 194
 195         return -EINVAL;
 196 }
 197
 198 static struct gpio_chip ab8500gpio_chip = {
 199         .label                  = "ab8500_gpio",
 200         .owner                  = THIS_MODULE,
 201         .direction_input        = ab8500_gpio_direction_input,
 202         .get                    = ab8500_gpio_get,
 203         .direction_output       = ab8500_gpio_direction_output,
 204         .set                    = ab8500_gpio_set,
 205         .to_irq                 = ab8500_gpio_to_irq,
 206 };
 207
 208 static unsigned int irq_to_rising(unsigned int irq)
 209 {
 210         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 211         int offset = irq - ab8500_gpio->irq_base;
 212         int new_irq = offset +  AB8500_INT_GPIO6R
 213                         + ab8500_gpio->parent->irq_base;
 214         return new_irq;
 215 }
 216
 217 static unsigned int irq_to_falling(unsigned int irq)
 218 {
 219         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 220         int offset = irq - ab8500_gpio->irq_base;
 221         int new_irq = offset +  AB8500_INT_GPIO6F
 222                         +  ab8500_gpio->parent->irq_base;
 223         return new_irq;
 224
 225 }
 226
 227 static unsigned int rising_to_irq(unsigned int irq, void *dev)
 228 {
 229         struct ab8500_gpio *ab8500_gpio = dev;
 230         int offset = irq - AB8500_INT_GPIO6R
 231                         - ab8500_gpio->parent->irq_base ;
 232         int new_irq = offset + ab8500_gpio->irq_base;
 233         return new_irq;
 234 }
 235
 236 static unsigned int falling_to_irq(unsigned int irq, void *dev)
 237 {
 238         struct ab8500_gpio *ab8500_gpio = dev;
 239         int offset = irq - AB8500_INT_GPIO6F
 240                         - ab8500_gpio->parent->irq_base ;
 241         int new_irq = offset + ab8500_gpio->irq_base;
 242         return new_irq;
 243
 244 }
 245
 246 /*
 247  * IRQ handler
 248  */
 249
 250 static irqreturn_t handle_rising(int irq, void *dev)
 251 {
 252
 253         handle_nested_irq(rising_to_irq(irq , dev));
 254         return IRQ_HANDLED;
 255 }
 256
 257 static irqreturn_t handle_falling(int irq, void *dev)
 258 {
 259
 260         handle_nested_irq(falling_to_irq(irq, dev));
 261         return IRQ_HANDLED;
 262 }
 263
 264 static void ab8500_gpio_irq_lock(unsigned int irq)
 265 {
 266         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 267         mutex_lock(&ab8500_gpio->lock);
 268 }
 269
 270 static void ab8500_gpio_irq_sync_unlock(unsigned int irq)
 271 {
 272         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 273         int offset = irq - ab8500_gpio->irq_base;
 274         bool rising = ab8500_gpio->rising & BIT(offset);
 275         bool falling = ab8500_gpio->falling & BIT(offset);
 276         int ret;
 277
 278         switch (ab8500_gpio->irq_action)        {
 279         case STARTUP:
 280                 if (rising)
 281                         ret = request_threaded_irq(irq_to_rising(irq),
 282                                         NULL, handle_rising,
 283                                         IRQF_TRIGGER_RISING,
 284                                         "ab8500-gpio-r", ab8500_gpio);
 285                 if (falling)
 286                         ret = request_threaded_irq(irq_to_falling(irq),
 287                                        NULL, handle_falling,
 288                                        IRQF_TRIGGER_FALLING,
 289                                        "ab8500-gpio-f", ab8500_gpio);
 290                 break;
 291         case SHUTDOWN:
 292                 if (rising)
 293                         free_irq(irq_to_rising(irq), ab8500_gpio);
 294                 if (falling)
 295                         free_irq(irq_to_falling(irq), ab8500_gpio);
 296                 break;
 297         case MASK:
 298                 if (rising)
 299                         disable_irq(irq_to_rising(irq));
 300                 if (falling)
 301                         disable_irq(irq_to_falling(irq));
 302                 break;
 303         case UNMASK:
 304                 if (rising)
 305                         enable_irq(irq_to_rising(irq));
 306                 if (falling)
 307                         enable_irq(irq_to_falling(irq));
 308                 break;
 309         case NONE:
 310                 break;
 311         }
 312         ab8500_gpio->irq_action = NONE;
 313         ab8500_gpio->rising &= ~(BIT(offset));
 314         ab8500_gpio->falling &= ~(BIT(offset));
 315         mutex_unlock(&ab8500_gpio->lock);
 316 }
 317
 318
 319 static void ab8500_gpio_irq_mask(unsigned int irq)
 320 {
 321         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 322         ab8500_gpio->irq_action = MASK;
 323 }
 324
 325 static void ab8500_gpio_irq_unmask(unsigned int irq)
 326 {
 327         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 328         ab8500_gpio->irq_action = UNMASK;
 329 }
 330
 331 static int ab8500_gpio_irq_set_type(unsigned int irq, unsigned int type)
 332 {
 333         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 334         int offset = irq - ab8500_gpio->irq_base;
 335
 336         if (type == IRQ_TYPE_EDGE_BOTH) {
 337                 ab8500_gpio->rising =  BIT(offset);
 338                 ab8500_gpio->falling = BIT(offset);
 339         } else if (type == IRQ_TYPE_EDGE_RISING) {
 340                 ab8500_gpio->rising =  BIT(offset);
 341         } else  {
 342                 ab8500_gpio->falling = BIT(offset);
 343         }
 344         return 0;
 345 }
 346
 347 unsigned int ab8500_gpio_irq_startup(unsigned int irq)
 348 {
 349         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 350         ab8500_gpio->irq_action = STARTUP;
 351         return 0;
 352 }
 353
 354 void ab8500_gpio_irq_shutdown(unsigned int irq)
 355 {
 356         struct ab8500_gpio *ab8500_gpio = get_irq_chip_data(irq);
 357         ab8500_gpio->irq_action = SHUTDOWN;
 358 }
 359
 360 static struct irq_chip ab8500_gpio_irq_chip = {
 361         .name                   = "ab8500-gpio",
 362         .startup                = ab8500_gpio_irq_startup,
 363         .shutdown               = ab8500_gpio_irq_shutdown,
 364         .bus_lock               = ab8500_gpio_irq_lock,
 365         .bus_sync_unlock        = ab8500_gpio_irq_sync_unlock,
 366         .mask                   = ab8500_gpio_irq_mask,
 367         .unmask                 = ab8500_gpio_irq_unmask,
 368         .set_type               = ab8500_gpio_irq_set_type,
 369 };
 370
 371 static int ab8500_gpio_irq_init(struct ab8500_gpio *ab8500_gpio)
 372 {
 373         u32 base = ab8500_gpio->irq_base;
 374         int irq;
 375
 376         for (irq = base; irq < base + AB8500_NUM_VIR_GPIO_IRQ ; irq++) {
 377                 set_irq_chip_data(irq, ab8500_gpio);
 378                 set_irq_chip_and_handler(irq, &ab8500_gpio_irq_chip,
 379                                 handle_simple_irq);
 380                 set_irq_nested_thread(irq, 1);
 381 #ifdef CONFIG_ARM
 382                 set_irq_flags(irq, IRQF_VALID);
 383 #else
 384                 set_irq_noprobe(irq);
 385 #endif
 386         }
 387
 388         return 0;
 389 }
 390
 391 static void ab8500_gpio_irq_remove(struct ab8500_gpio *ab8500_gpio)
 392 {
 393         int base = ab8500_gpio->irq_base;
 394         int irq;
 395
 396         for (irq = base; irq < base + AB8500_NUM_VIR_GPIO_IRQ; irq++) {
 397 #ifdef CONFIG_ARM
 398                 set_irq_flags(irq, 0);
 399 #endif
 400                 set_irq_chip_and_handler(irq, NULL, NULL);
 401                 set_irq_chip_data(irq, NULL);
 402         }
 403 }
 404
 405 static int __devinit ab8500_gpio_probe(struct platform_device *pdev)
 406 {
 407         struct ab8500_platform_data *ab8500_pdata =
 408                                 dev_get_platdata(pdev->dev.parent);
 409         struct ab8500_gpio_platform_data *pdata;
 410         struct ab8500_gpio *ab8500_gpio;
 411         int ret;
 412         int i;
 413
 414         pdata = ab8500_pdata->gpio;
 415         if (!pdata)     {
 416                 dev_err(&pdev->dev, "gpio platform data missing\n");
 417                 return -ENODEV;
 418         }
 419
 420         ab8500_gpio = kzalloc(sizeof(struct ab8500_gpio), GFP_KERNEL);
 421         if (ab8500_gpio == NULL) {
 422                 dev_err(&pdev->dev, "failed to allocate memory\n");
 423                 return -ENOMEM;
 424         }
 425         ab8500_gpio->dev = &pdev->dev;
 426         ab8500_gpio->parent = dev_get_drvdata(pdev->dev.parent);
 427         ab8500_gpio->chip = ab8500gpio_chip;
 428         ab8500_gpio->chip.ngpio = AB8500_NUM_GPIO;
 429         ab8500_gpio->chip.dev = &pdev->dev;
 430         ab8500_gpio->chip.base = pdata->gpio_base;
 431         ab8500_gpio->irq_base = pdata->irq_base;
 432         /* initialize the lock */
 433         mutex_init(&ab8500_gpio->lock);
 434         /*
 435          * AB8500 core will handle and clear the IRQ
 436          * configre GPIO based on config-reg value.
 437          * These values are for selecting the PINs as
 438          * GPIO or alternate function
 439          */
 440         for (i = AB8500_GPIO_SEL1_REG; i <= AB8500_GPIO_SEL6_REG; i++)  {
 441                 ret = abx500_set_register_interruptible(ab8500_gpio->dev,
 442                                 AB8500_MISC, i,
 443                                 pdata->config_reg[i]);
 444                 if (ret < 0)
 445                         goto out_free;
 446         }
 447         ret = abx500_set_register_interruptible(ab8500_gpio->dev, AB8500_MISC,
 448                                 AB8500_GPIO_ALTFUN_REG,
 449                                 pdata->config_reg[ALTFUN_REG_INDEX]);
 450         if (ret < 0)
 451                 goto out_free;
 452
 453         ret = ab8500_gpio_irq_init(ab8500_gpio);
 454         if (ret)
 455                 goto out_free;
 456         ret = gpiochip_add(&ab8500_gpio->chip);
 457         if (ret) {
 458                 dev_err(&pdev->dev, "unable to add gpiochip: %d\n",
 459                                 ret);
 460                 goto out_rem_irq;
 461         }
 462         platform_set_drvdata(pdev, ab8500_gpio);
 463         return 0;
 464
 465 out_rem_irq:
 466         ab8500_gpio_irq_remove(ab8500_gpio);
 467 out_free:
 468         mutex_destroy(&ab8500_gpio->lock);
 469         kfree(ab8500_gpio);
 470         return ret;
 471 }
 472
 473 /*
 474  * ab8500_gpio_remove() - remove Ab8500-gpio driver
 475  * @pdev :      Platform device registered
 476  */
 477 static int __devexit ab8500_gpio_remove(struct platform_device *pdev)
 478 {
 479         struct ab8500_gpio *ab8500_gpio = platform_get_drvdata(pdev);
 480         int ret;
 481
 482         ret = gpiochip_remove(&ab8500_gpio->chip);
 483         if (ret < 0) {
 484                 dev_err(ab8500_gpio->dev, "unable to remove gpiochip: %d\n",
 485                         ret);
 486                 return ret;
 487         }
 488
 489         platform_set_drvdata(pdev, NULL);
 490         mutex_destroy(&ab8500_gpio->lock);
 491         kfree(ab8500_gpio);
 492
 493         return 0;
 494 }
 495
 496 static struct platform_driver ab8500_gpio_driver = {
 497         .driver = {
 498                 .name = "ab8500-gpio",
 499                 .owner = THIS_MODULE,
 500         },
 501         .probe = ab8500_gpio_probe,
 502         .remove = __devexit_p(ab8500_gpio_remove),
 503 };
 504
 505 static int __init ab8500_gpio_init(void)
 506 {
 507         return platform_driver_register(&ab8500_gpio_driver);
 508 }
 509 arch_initcall(ab8500_gpio_init);
 510
 511 static void __exit ab8500_gpio_exit(void)
 512 {
 513         platform_driver_unregister(&ab8500_gpio_driver);
 514 }
 515 module_exit(ab8500_gpio_exit);
 516
 517 MODULE_AUTHOR("BIBEK BASU <bibek.basu@stericsson.com>");
 518 MODULE_DESCRIPTION("Driver allows to use AB8500 unused pins to be used as GPIO");
 519 MODULE_ALIAS("platform:ab8500-gpio");
 520 MODULE_LICENSE("GPL v2");