drivers/gpio/gpio-twl4030.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Access to GPIOs on TWL4030/TPS659x0 chips
   4  *
   5  * Copyright (C) 2006-2007 Texas Instruments, Inc.
   6  * Copyright (C) 2006 MontaVista Software, Inc.
   7  *
   8  * Code re-arranged and cleaned up by:
   9  *      Syed Mohammed Khasim <x0khasim@ti.com>
  10  *
  11  * Initial Code:
  12  *      Andy Lowe / Nishanth Menon
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/kthread.h>
  19 #include <linux/irq.h>
  20 #include <linux/gpio/machine.h>
  21 #include <linux/gpio/driver.h>
  22 #include <linux/gpio/consumer.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/of.h>
  25 #include <linux/irqdomain.h>
  26
  27 #include <linux/mfd/twl.h>
  28
  29 /*
  30  * The GPIO "subchip" supports 18 GPIOs which can be configured as
  31  * inputs or outputs, with pullups or pulldowns on each pin.  Each
  32  * GPIO can trigger interrupts on either or both edges.
  33  *
  34  * GPIO interrupts can be fed to either of two IRQ lines; this is
  35  * intended to support multiple hosts.
  36  *
  37  * There are also two LED pins used sometimes as output-only GPIOs.
  38  */
  39
  40 /* genirq interfaces are not available to modules */
  41 #ifdef MODULE
  42 #define is_module()     true
  43 #else
  44 #define is_module()     false
  45 #endif
  46
  47 /* GPIO_CTRL Fields */
  48 #define MASK_GPIO_CTRL_GPIO0CD1         BIT(0)
  49 #define MASK_GPIO_CTRL_GPIO1CD2         BIT(1)
  50 #define MASK_GPIO_CTRL_GPIO_ON          BIT(2)
  51
  52 /* Mask for GPIO registers when aggregated into a 32-bit integer */
  53 #define GPIO_32_MASK                    0x0003ffff
  54
  55 struct gpio_twl4030_priv {
  56         struct gpio_chip gpio_chip;
  57         struct mutex mutex;
  58         int irq_base;
  59
  60         /* Bitfields for state caching */
  61         unsigned int usage_count;
  62         unsigned int direction;
  63         unsigned int out_state;
  64 };
  65
  66 /*----------------------------------------------------------------------*/
  67
  68 /*
  69  * To configure TWL4030 GPIO module registers
  70  */
  71 static inline int gpio_twl4030_write(u8 address, u8 data)
  72 {
  73         return twl_i2c_write_u8(TWL4030_MODULE_GPIO, data, address);
  74 }
  75
  76 /*----------------------------------------------------------------------*/
  77
  78 /*
  79  * LED register offsets from TWL_MODULE_LED base
  80  * PWMs A and B are dedicated to LEDs A and B, respectively.
  81  */
  82
  83 #define TWL4030_LED_LEDEN_REG   0x00
  84 #define TWL4030_PWMAON_REG      0x01
  85 #define TWL4030_PWMAOFF_REG     0x02
  86 #define TWL4030_PWMBON_REG      0x03
  87 #define TWL4030_PWMBOFF_REG     0x04
  88
  89 /* LEDEN bits */
  90 #define LEDEN_LEDAON            BIT(0)
  91 #define LEDEN_LEDBON            BIT(1)
  92 #define LEDEN_LEDAEXT           BIT(2)
  93 #define LEDEN_LEDBEXT           BIT(3)
  94 #define LEDEN_LEDAPWM           BIT(4)
  95 #define LEDEN_LEDBPWM           BIT(5)
  96 #define LEDEN_PWM_LENGTHA       BIT(6)
  97 #define LEDEN_PWM_LENGTHB       BIT(7)
  98
  99 #define PWMxON_LENGTH           BIT(7)
 100
 101 /*----------------------------------------------------------------------*/
 102
 103 /*
 104  * To read a TWL4030 GPIO module register
 105  */
 106 static inline int gpio_twl4030_read(u8 address)
 107 {
 108         u8 data;
 109         int ret = 0;
 110
 111         ret = twl_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address);
 112         return (ret < 0) ? ret : data;
 113 }
 114
 115 /*----------------------------------------------------------------------*/
 116
 117 static u8 cached_leden;
 118
 119 /* The LED lines are open drain outputs ... a FET pulls to GND, so an
 120  * external pullup is needed.  We could also expose the integrated PWM
 121  * as a LED brightness control; we initialize it as "always on".
 122  */
 123 static void twl4030_led_set_value(int led, int value)
 124 {
 125         u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM;
 126
 127         if (led)
 128                 mask <<= 1;
 129
 130         if (value)
 131                 cached_leden &= ~mask;
 132         else
 133                 cached_leden |= mask;
 134
 135         WARN_ON_ONCE(twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
 136                                       TWL4030_LED_LEDEN_REG));
 137 }
 138
 139 static int twl4030_set_gpio_direction(int gpio, int is_input)
 140 {
 141         u8 d_bnk = gpio >> 3;
 142         u8 d_msk = BIT(gpio & 0x7);
 143         u8 reg = 0;
 144         u8 base = REG_GPIODATADIR1 + d_bnk;
 145         int ret = 0;
 146
 147         ret = gpio_twl4030_read(base);
 148         if (ret >= 0) {
 149                 if (is_input)
 150                         reg = ret & ~d_msk;
 151                 else
 152                         reg = ret | d_msk;
 153
 154                 ret = gpio_twl4030_write(base, reg);
 155         }
 156         return ret;
 157 }
 158
 159 static int twl4030_get_gpio_direction(int gpio)
 160 {
 161         u8 d_bnk = gpio >> 3;
 162         u8 d_msk = BIT(gpio & 0x7);
 163         u8 base = REG_GPIODATADIR1 + d_bnk;
 164         int ret = 0;
 165
 166         ret = gpio_twl4030_read(base);
 167         if (ret < 0)
 168                 return ret;
 169
 170         if (ret & d_msk)
 171                 return GPIO_LINE_DIRECTION_OUT;
 172
 173         return GPIO_LINE_DIRECTION_IN;
 174 }
 175
 176 static int twl4030_set_gpio_dataout(int gpio, int enable)
 177 {
 178         u8 d_bnk = gpio >> 3;
 179         u8 d_msk = BIT(gpio & 0x7);
 180         u8 base = 0;
 181
 182         if (enable)
 183                 base = REG_SETGPIODATAOUT1 + d_bnk;
 184         else
 185                 base = REG_CLEARGPIODATAOUT1 + d_bnk;
 186
 187         return gpio_twl4030_write(base, d_msk);
 188 }
 189
 190 static int twl4030_get_gpio_datain(int gpio)
 191 {
 192         u8 d_bnk = gpio >> 3;
 193         u8 d_off = gpio & 0x7;
 194         u8 base = 0;
 195         int ret = 0;
 196
 197         base = REG_GPIODATAIN1 + d_bnk;
 198         ret = gpio_twl4030_read(base);
 199         if (ret > 0)
 200                 ret = (ret >> d_off) & 0x1;
 201
 202         return ret;
 203 }
 204
 205 /*----------------------------------------------------------------------*/
 206
 207 static int twl_request(struct gpio_chip *chip, unsigned offset)
 208 {
 209         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 210         int status = 0;
 211
 212         mutex_lock(&priv->mutex);
 213
 214         /* Support the two LED outputs as output-only GPIOs. */
 215         if (offset >= TWL4030_GPIO_MAX) {
 216                 u8      ledclr_mask = LEDEN_LEDAON | LEDEN_LEDAEXT
 217                                 | LEDEN_LEDAPWM | LEDEN_PWM_LENGTHA;
 218                 u8      reg = TWL4030_PWMAON_REG;
 219
 220                 offset -= TWL4030_GPIO_MAX;
 221                 if (offset) {
 222                         ledclr_mask <<= 1;
 223                         reg = TWL4030_PWMBON_REG;
 224                 }
 225
 226                 /* initialize PWM to always-drive */
 227                 /* Configure PWM OFF register first */
 228                 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg + 1);
 229                 if (status < 0)
 230                         goto done;
 231
 232                 /* Followed by PWM ON register */
 233                 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg);
 234                 if (status < 0)
 235                         goto done;
 236
 237                 /* init LED to not-driven (high) */
 238                 status = twl_i2c_read_u8(TWL4030_MODULE_LED, &cached_leden,
 239                                          TWL4030_LED_LEDEN_REG);
 240                 if (status < 0)
 241                         goto done;
 242                 cached_leden &= ~ledclr_mask;
 243                 status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
 244                                           TWL4030_LED_LEDEN_REG);
 245                 if (status < 0)
 246                         goto done;
 247
 248                 status = 0;
 249                 goto done;
 250         }
 251
 252         /* on first use, turn GPIO module "on" */
 253         if (!priv->usage_count) {
 254                 struct twl4030_gpio_platform_data *pdata;
 255                 u8 value = MASK_GPIO_CTRL_GPIO_ON;
 256
 257                 /* optionally have the first two GPIOs switch vMMC1
 258                  * and vMMC2 power supplies based on card presence.
 259                  */
 260                 pdata = dev_get_platdata(chip->parent);
 261                 if (pdata)
 262                         value |= pdata->mmc_cd & 0x03;
 263
 264                 status = gpio_twl4030_write(REG_GPIO_CTRL, value);
 265         }
 266
 267 done:
 268         if (!status)
 269                 priv->usage_count |= BIT(offset);
 270
 271         mutex_unlock(&priv->mutex);
 272         return status;
 273 }
 274
 275 static void twl_free(struct gpio_chip *chip, unsigned offset)
 276 {
 277         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 278
 279         mutex_lock(&priv->mutex);
 280         if (offset >= TWL4030_GPIO_MAX) {
 281                 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1);
 282                 goto out;
 283         }
 284
 285         priv->usage_count &= ~BIT(offset);
 286
 287         /* on last use, switch off GPIO module */
 288         if (!priv->usage_count)
 289                 gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
 290
 291 out:
 292         mutex_unlock(&priv->mutex);
 293 }
 294
 295 static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
 296 {
 297         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 298         int ret;
 299
 300         mutex_lock(&priv->mutex);
 301         if (offset < TWL4030_GPIO_MAX)
 302                 ret = twl4030_set_gpio_direction(offset, 1);
 303         else
 304                 ret = -EINVAL;  /* LED outputs can't be set as input */
 305
 306         if (!ret)
 307                 priv->direction &= ~BIT(offset);
 308
 309         mutex_unlock(&priv->mutex);
 310
 311         return ret;
 312 }
 313
 314 static int twl_get(struct gpio_chip *chip, unsigned offset)
 315 {
 316         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 317         int ret;
 318         int status = 0;
 319
 320         mutex_lock(&priv->mutex);
 321         if (!(priv->usage_count & BIT(offset))) {
 322                 ret = -EPERM;
 323                 goto out;
 324         }
 325
 326         if (priv->direction & BIT(offset))
 327                 status = priv->out_state & BIT(offset);
 328         else
 329                 status = twl4030_get_gpio_datain(offset);
 330
 331         ret = (status < 0) ? status : !!status;
 332 out:
 333         mutex_unlock(&priv->mutex);
 334         return ret;
 335 }
 336
 337 static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
 338 {
 339         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 340
 341         mutex_lock(&priv->mutex);
 342         if (offset < TWL4030_GPIO_MAX)
 343                 twl4030_set_gpio_dataout(offset, value);
 344         else
 345                 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
 346
 347         if (value)
 348                 priv->out_state |= BIT(offset);
 349         else
 350                 priv->out_state &= ~BIT(offset);
 351
 352         mutex_unlock(&priv->mutex);
 353 }
 354
 355 static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
 356 {
 357         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 358         int ret = 0;
 359
 360         mutex_lock(&priv->mutex);
 361         if (offset < TWL4030_GPIO_MAX) {
 362                 ret = twl4030_set_gpio_direction(offset, 0);
 363                 if (ret) {
 364                         mutex_unlock(&priv->mutex);
 365                         return ret;
 366                 }
 367         }
 368
 369         /*
 370          *  LED gpios i.e. offset >= TWL4030_GPIO_MAX are always output
 371          */
 372
 373         priv->direction |= BIT(offset);
 374         mutex_unlock(&priv->mutex);
 375
 376         twl_set(chip, offset, value);
 377
 378         return ret;
 379 }
 380
 381 static int twl_get_direction(struct gpio_chip *chip, unsigned offset)
 382 {
 383         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 384         /*
 385          * Default GPIO_LINE_DIRECTION_OUT
 386          * LED GPIOs >= TWL4030_GPIO_MAX are always output
 387          */
 388         int ret = GPIO_LINE_DIRECTION_OUT;
 389
 390         mutex_lock(&priv->mutex);
 391         if (offset < TWL4030_GPIO_MAX) {
 392                 ret = twl4030_get_gpio_direction(offset);
 393                 if (ret) {
 394                         mutex_unlock(&priv->mutex);
 395                         return ret;
 396                 }
 397         }
 398         mutex_unlock(&priv->mutex);
 399
 400         return ret;
 401 }
 402
 403 static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
 404 {
 405         struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
 406
 407         return (priv->irq_base && (offset < TWL4030_GPIO_MAX))
 408                 ? (priv->irq_base + offset)
 409                 : -EINVAL;
 410 }
 411
 412 static const struct gpio_chip template_chip = {
 413         .label                  = "twl4030",
 414         .owner                  = THIS_MODULE,
 415         .request                = twl_request,
 416         .free                   = twl_free,
 417         .direction_input        = twl_direction_in,
 418         .direction_output       = twl_direction_out,
 419         .get_direction          = twl_get_direction,
 420         .get                    = twl_get,
 421         .set                    = twl_set,
 422         .to_irq                 = twl_to_irq,
 423         .can_sleep              = true,
 424 };
 425
 426 /*----------------------------------------------------------------------*/
 427
 428 static int gpio_twl4030_pulls(u32 ups, u32 downs)
 429 {
 430         u8              message[5];
 431         unsigned        i, gpio_bit;
 432
 433         /* For most pins, a pulldown was enabled by default.
 434          * We should have data that's specific to this board.
 435          */
 436         for (gpio_bit = 1, i = 0; i < 5; i++) {
 437                 u8              bit_mask;
 438                 unsigned        j;
 439
 440                 for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) {
 441                         if (ups & gpio_bit)
 442                                 bit_mask |= 1 << (j + 1);
 443                         else if (downs & gpio_bit)
 444                                 bit_mask |= 1 << (j + 0);
 445                 }
 446                 message[i] = bit_mask;
 447         }
 448
 449         return twl_i2c_write(TWL4030_MODULE_GPIO, message,
 450                                 REG_GPIOPUPDCTR1, 5);
 451 }
 452
 453 static int gpio_twl4030_debounce(u32 debounce, u8 mmc_cd)
 454 {
 455         u8              message[3];
 456
 457         /* 30 msec of debouncing is always used for MMC card detect,
 458          * and is optional for everything else.
 459          */
 460         message[0] = (debounce & 0xff) | (mmc_cd & 0x03);
 461         debounce >>= 8;
 462         message[1] = (debounce & 0xff);
 463         debounce >>= 8;
 464         message[2] = (debounce & 0x03);
 465
 466         return twl_i2c_write(TWL4030_MODULE_GPIO, message,
 467                                 REG_GPIO_DEBEN1, 3);
 468 }
 469
 470 static struct twl4030_gpio_platform_data *of_gpio_twl4030(struct device *dev)
 471 {
 472         struct twl4030_gpio_platform_data *omap_twl_info;
 473
 474         omap_twl_info = devm_kzalloc(dev, sizeof(*omap_twl_info), GFP_KERNEL);
 475         if (!omap_twl_info)
 476                 return NULL;
 477
 478         omap_twl_info->use_leds = of_property_read_bool(dev->of_node,
 479                         "ti,use-leds");
 480
 481         of_property_read_u32(dev->of_node, "ti,debounce",
 482                              &omap_twl_info->debounce);
 483         of_property_read_u32(dev->of_node, "ti,mmc-cd",
 484                              (u32 *)&omap_twl_info->mmc_cd);
 485         of_property_read_u32(dev->of_node, "ti,pullups",
 486                              &omap_twl_info->pullups);
 487         of_property_read_u32(dev->of_node, "ti,pulldowns",
 488                              &omap_twl_info->pulldowns);
 489
 490         return omap_twl_info;
 491 }
 492
 493 /* Called from the registered devm action */
 494 static void gpio_twl4030_power_off_action(void *data)
 495 {
 496         struct gpio_desc *d = data;
 497
 498         gpiod_unexport(d);
 499         gpiochip_free_own_desc(d);
 500 }
 501
 502 static int gpio_twl4030_probe(struct platform_device *pdev)
 503 {
 504         struct twl4030_gpio_platform_data *pdata;
 505         struct device_node *node = pdev->dev.of_node;
 506         struct gpio_twl4030_priv *priv;
 507         int ret, irq_base;
 508
 509         priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_twl4030_priv),
 510                             GFP_KERNEL);
 511         if (!priv)
 512                 return -ENOMEM;
 513
 514         /* maybe setup IRQs */
 515         if (is_module()) {
 516                 dev_err(&pdev->dev, "can't dispatch IRQs from modules\n");
 517                 goto no_irqs;
 518         }
 519
 520         irq_base = devm_irq_alloc_descs(&pdev->dev, -1,
 521                                         0, TWL4030_GPIO_MAX, 0);
 522         if (irq_base < 0) {
 523                 dev_err(&pdev->dev, "Failed to alloc irq_descs\n");
 524                 return irq_base;
 525         }
 526
 527         irq_domain_add_legacy(node, TWL4030_GPIO_MAX, irq_base, 0,
 528                               &irq_domain_simple_ops, NULL);
 529
 530         ret = twl4030_sih_setup(&pdev->dev, TWL4030_MODULE_GPIO, irq_base);
 531         if (ret < 0)
 532                 return ret;
 533
 534         priv->irq_base = irq_base;
 535
 536 no_irqs:
 537         priv->gpio_chip = template_chip;
 538         priv->gpio_chip.base = -1;
 539         priv->gpio_chip.ngpio = TWL4030_GPIO_MAX;
 540         priv->gpio_chip.parent = &pdev->dev;
 541
 542         mutex_init(&priv->mutex);
 543
 544         pdata = of_gpio_twl4030(&pdev->dev);
 545         if (pdata == NULL) {
 546                 dev_err(&pdev->dev, "Platform data is missing\n");
 547                 return -ENXIO;
 548         }
 549
 550         /*
 551          * NOTE:  boards may waste power if they don't set pullups
 552          * and pulldowns correctly ... default for non-ULPI pins is
 553          * pulldown, and some other pins may have external pullups
 554          * or pulldowns.  Careful!
 555          */
 556         ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns);
 557         if (ret)
 558                 dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n",
 559                         pdata->pullups, pdata->pulldowns, ret);
 560
 561         ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd);
 562         if (ret)
 563                 dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n",
 564                         pdata->debounce, pdata->mmc_cd, ret);
 565
 566         /*
 567          * NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE,
 568          * is (still) clear if use_leds is set.
 569          */
 570         if (pdata->use_leds)
 571                 priv->gpio_chip.ngpio += 2;
 572
 573         ret = devm_gpiochip_add_data(&pdev->dev, &priv->gpio_chip, priv);
 574         if (ret < 0) {
 575                 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
 576                 priv->gpio_chip.ngpio = 0;
 577                 return ret;
 578         }
 579
 580         /*
 581          * Special quirk for the OMAP3 to hog and export a WLAN power
 582          * GPIO.
 583          */
 584         if (IS_ENABLED(CONFIG_ARCH_OMAP3) &&
 585             of_machine_is_compatible("compulab,omap3-sbc-t3730")) {
 586                 struct gpio_desc *d;
 587
 588                 d = gpiochip_request_own_desc(&priv->gpio_chip,
 589                                                  2, "wlan pwr",
 590                                                  GPIO_ACTIVE_HIGH,
 591                                                  GPIOD_OUT_HIGH);
 592                 if (IS_ERR(d))
 593                         return dev_err_probe(&pdev->dev, PTR_ERR(d),
 594                                              "unable to hog wlan pwr GPIO\n");
 595
 596                 gpiod_export(d, 0);
 597
 598                 ret = devm_add_action_or_reset(&pdev->dev, gpio_twl4030_power_off_action, d);
 599                 if (ret)
 600                         return dev_err_probe(&pdev->dev, ret,
 601                                              "failed to install power off handler\n");
 602
 603         }
 604
 605         return 0;
 606 }
 607
 608 static const struct of_device_id twl_gpio_match[] = {
 609         { .compatible = "ti,twl4030-gpio", },
 610         { },
 611 };
 612 MODULE_DEVICE_TABLE(of, twl_gpio_match);
 613
 614 /* Note:  this hardware lives inside an I2C-based multi-function device. */
 615 MODULE_ALIAS("platform:twl4030_gpio");
 616
 617 static struct platform_driver gpio_twl4030_driver = {
 618         .driver = {
 619                 .name   = "twl4030_gpio",
 620                 .of_match_table = twl_gpio_match,
 621         },
 622         .probe          = gpio_twl4030_probe,
 623 };
 624
 625 static int __init gpio_twl4030_init(void)
 626 {
 627         return platform_driver_register(&gpio_twl4030_driver);
 628 }
 629 subsys_initcall(gpio_twl4030_init);
 630
 631 static void __exit gpio_twl4030_exit(void)
 632 {
 633         platform_driver_unregister(&gpio_twl4030_driver);
 634 }
 635 module_exit(gpio_twl4030_exit);
 636
 637 MODULE_AUTHOR("Texas Instruments, Inc.");
 638 MODULE_DESCRIPTION("GPIO interface for TWL4030");
 639 MODULE_LICENSE("GPL");