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/driver.h> 21 #include <linux/platform_device.h> 22 #include <linux/of.h> 23 #include <linux/irqdomain.h> 24 25 #include <linux/mfd/twl.h> 26 27 /* 28 * The GPIO "subchip" supports 18 GPIOs which can be configured as 29 * inputs or outputs, with pullups or pulldowns on each pin. Each 30 * GPIO can trigger interrupts on either or both edges. 31 * 32 * GPIO interrupts can be fed to either of two IRQ lines; this is 33 * intended to support multiple hosts. 34 * 35 * There are also two LED pins used sometimes as output-only GPIOs. 36 */ 37 38 /* genirq interfaces are not available to modules */ 39 #ifdef MODULE 40 #define is_module() true 41 #else 42 #define is_module() false 43 #endif 44 45 /* GPIO_CTRL Fields */ 46 #define MASK_GPIO_CTRL_GPIO0CD1 BIT(0) 47 #define MASK_GPIO_CTRL_GPIO1CD2 BIT(1) 48 #define MASK_GPIO_CTRL_GPIO_ON BIT(2) 49 50 /* Mask for GPIO registers when aggregated into a 32-bit integer */ 51 #define GPIO_32_MASK 0x0003ffff 52 53 struct gpio_twl4030_priv { 54 struct gpio_chip gpio_chip; 55 struct mutex mutex; 56 int irq_base; 57 58 /* Bitfields for state caching */ 59 unsigned int usage_count; 60 unsigned int direction; 61 unsigned int out_state; 62 }; 63 64 /*----------------------------------------------------------------------*/ 65 66 /* 67 * To configure TWL4030 GPIO module registers 68 */ 69 static inline int gpio_twl4030_write(u8 address, u8 data) 70 { 71 return twl_i2c_write_u8(TWL4030_MODULE_GPIO, data, address); 72 } 73 74 /*----------------------------------------------------------------------*/ 75 76 /* 77 * LED register offsets from TWL_MODULE_LED base 78 * PWMs A and B are dedicated to LEDs A and B, respectively. 79 */ 80 81 #define TWL4030_LED_LEDEN_REG 0x00 82 #define TWL4030_PWMAON_REG 0x01 83 #define TWL4030_PWMAOFF_REG 0x02 84 #define TWL4030_PWMBON_REG 0x03 85 #define TWL4030_PWMBOFF_REG 0x04 86 87 /* LEDEN bits */ 88 #define LEDEN_LEDAON BIT(0) 89 #define LEDEN_LEDBON BIT(1) 90 #define LEDEN_LEDAEXT BIT(2) 91 #define LEDEN_LEDBEXT BIT(3) 92 #define LEDEN_LEDAPWM BIT(4) 93 #define LEDEN_LEDBPWM BIT(5) 94 #define LEDEN_PWM_LENGTHA BIT(6) 95 #define LEDEN_PWM_LENGTHB BIT(7) 96 97 #define PWMxON_LENGTH BIT(7) 98 99 /*----------------------------------------------------------------------*/ 100 101 /* 102 * To read a TWL4030 GPIO module register 103 */ 104 static inline int gpio_twl4030_read(u8 address) 105 { 106 u8 data; 107 int ret = 0; 108 109 ret = twl_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address); 110 return (ret < 0) ? ret : data; 111 } 112 113 /*----------------------------------------------------------------------*/ 114 115 static u8 cached_leden; 116 117 /* The LED lines are open drain outputs ... a FET pulls to GND, so an 118 * external pullup is needed. We could also expose the integrated PWM 119 * as a LED brightness control; we initialize it as "always on". 120 */ 121 static void twl4030_led_set_value(int led, int value) 122 { 123 u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM; 124 125 if (led) 126 mask <<= 1; 127 128 if (value) 129 cached_leden &= ~mask; 130 else 131 cached_leden |= mask; 132 133 WARN_ON_ONCE(twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden, 134 TWL4030_LED_LEDEN_REG)); 135 } 136 137 static int twl4030_set_gpio_direction(int gpio, int is_input) 138 { 139 u8 d_bnk = gpio >> 3; 140 u8 d_msk = BIT(gpio & 0x7); 141 u8 reg = 0; 142 u8 base = REG_GPIODATADIR1 + d_bnk; 143 int ret = 0; 144 145 ret = gpio_twl4030_read(base); 146 if (ret >= 0) { 147 if (is_input) 148 reg = ret & ~d_msk; 149 else 150 reg = ret | d_msk; 151 152 ret = gpio_twl4030_write(base, reg); 153 } 154 return ret; 155 } 156 157 static int twl4030_get_gpio_direction(int gpio) 158 { 159 u8 d_bnk = gpio >> 3; 160 u8 d_msk = BIT(gpio & 0x7); 161 u8 base = REG_GPIODATADIR1 + d_bnk; 162 int ret = 0; 163 164 ret = gpio_twl4030_read(base); 165 if (ret < 0) 166 return ret; 167 168 /* 1 = output, but gpiolib semantics are inverse so invert */ 169 ret = !(ret & d_msk); 170 171 return ret; 172 } 173 174 static int twl4030_set_gpio_dataout(int gpio, int enable) 175 { 176 u8 d_bnk = gpio >> 3; 177 u8 d_msk = BIT(gpio & 0x7); 178 u8 base = 0; 179 180 if (enable) 181 base = REG_SETGPIODATAOUT1 + d_bnk; 182 else 183 base = REG_CLEARGPIODATAOUT1 + d_bnk; 184 185 return gpio_twl4030_write(base, d_msk); 186 } 187 188 static int twl4030_get_gpio_datain(int gpio) 189 { 190 u8 d_bnk = gpio >> 3; 191 u8 d_off = gpio & 0x7; 192 u8 base = 0; 193 int ret = 0; 194 195 base = REG_GPIODATAIN1 + d_bnk; 196 ret = gpio_twl4030_read(base); 197 if (ret > 0) 198 ret = (ret >> d_off) & 0x1; 199 200 return ret; 201 } 202 203 /*----------------------------------------------------------------------*/ 204 205 static int twl_request(struct gpio_chip *chip, unsigned offset) 206 { 207 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 208 int status = 0; 209 210 mutex_lock(&priv->mutex); 211 212 /* Support the two LED outputs as output-only GPIOs. */ 213 if (offset >= TWL4030_GPIO_MAX) { 214 u8 ledclr_mask = LEDEN_LEDAON | LEDEN_LEDAEXT 215 | LEDEN_LEDAPWM | LEDEN_PWM_LENGTHA; 216 u8 reg = TWL4030_PWMAON_REG; 217 218 offset -= TWL4030_GPIO_MAX; 219 if (offset) { 220 ledclr_mask <<= 1; 221 reg = TWL4030_PWMBON_REG; 222 } 223 224 /* initialize PWM to always-drive */ 225 /* Configure PWM OFF register first */ 226 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg + 1); 227 if (status < 0) 228 goto done; 229 230 /* Followed by PWM ON register */ 231 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg); 232 if (status < 0) 233 goto done; 234 235 /* init LED to not-driven (high) */ 236 status = twl_i2c_read_u8(TWL4030_MODULE_LED, &cached_leden, 237 TWL4030_LED_LEDEN_REG); 238 if (status < 0) 239 goto done; 240 cached_leden &= ~ledclr_mask; 241 status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden, 242 TWL4030_LED_LEDEN_REG); 243 if (status < 0) 244 goto done; 245 246 status = 0; 247 goto done; 248 } 249 250 /* on first use, turn GPIO module "on" */ 251 if (!priv->usage_count) { 252 struct twl4030_gpio_platform_data *pdata; 253 u8 value = MASK_GPIO_CTRL_GPIO_ON; 254 255 /* optionally have the first two GPIOs switch vMMC1 256 * and vMMC2 power supplies based on card presence. 257 */ 258 pdata = dev_get_platdata(chip->parent); 259 if (pdata) 260 value |= pdata->mmc_cd & 0x03; 261 262 status = gpio_twl4030_write(REG_GPIO_CTRL, value); 263 } 264 265 done: 266 if (!status) 267 priv->usage_count |= BIT(offset); 268 269 mutex_unlock(&priv->mutex); 270 return status; 271 } 272 273 static void twl_free(struct gpio_chip *chip, unsigned offset) 274 { 275 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 276 277 mutex_lock(&priv->mutex); 278 if (offset >= TWL4030_GPIO_MAX) { 279 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1); 280 goto out; 281 } 282 283 priv->usage_count &= ~BIT(offset); 284 285 /* on last use, switch off GPIO module */ 286 if (!priv->usage_count) 287 gpio_twl4030_write(REG_GPIO_CTRL, 0x0); 288 289 out: 290 mutex_unlock(&priv->mutex); 291 } 292 293 static int twl_direction_in(struct gpio_chip *chip, unsigned offset) 294 { 295 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 296 int ret; 297 298 mutex_lock(&priv->mutex); 299 if (offset < TWL4030_GPIO_MAX) 300 ret = twl4030_set_gpio_direction(offset, 1); 301 else 302 ret = -EINVAL; /* LED outputs can't be set as input */ 303 304 if (!ret) 305 priv->direction &= ~BIT(offset); 306 307 mutex_unlock(&priv->mutex); 308 309 return ret; 310 } 311 312 static int twl_get(struct gpio_chip *chip, unsigned offset) 313 { 314 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 315 int ret; 316 int status = 0; 317 318 mutex_lock(&priv->mutex); 319 if (!(priv->usage_count & BIT(offset))) { 320 ret = -EPERM; 321 goto out; 322 } 323 324 if (priv->direction & BIT(offset)) 325 status = priv->out_state & BIT(offset); 326 else 327 status = twl4030_get_gpio_datain(offset); 328 329 ret = (status < 0) ? status : !!status; 330 out: 331 mutex_unlock(&priv->mutex); 332 return ret; 333 } 334 335 static void twl_set(struct gpio_chip *chip, unsigned offset, int value) 336 { 337 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 338 339 mutex_lock(&priv->mutex); 340 if (offset < TWL4030_GPIO_MAX) 341 twl4030_set_gpio_dataout(offset, value); 342 else 343 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value); 344 345 if (value) 346 priv->out_state |= BIT(offset); 347 else 348 priv->out_state &= ~BIT(offset); 349 350 mutex_unlock(&priv->mutex); 351 } 352 353 static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value) 354 { 355 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 356 int ret = 0; 357 358 mutex_lock(&priv->mutex); 359 if (offset < TWL4030_GPIO_MAX) { 360 ret = twl4030_set_gpio_direction(offset, 0); 361 if (ret) { 362 mutex_unlock(&priv->mutex); 363 return ret; 364 } 365 } 366 367 /* 368 * LED gpios i.e. offset >= TWL4030_GPIO_MAX are always output 369 */ 370 371 priv->direction |= BIT(offset); 372 mutex_unlock(&priv->mutex); 373 374 twl_set(chip, offset, value); 375 376 return ret; 377 } 378 379 static int twl_get_direction(struct gpio_chip *chip, unsigned offset) 380 { 381 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 382 /* 383 * Default 0 = output 384 * LED GPIOs >= TWL4030_GPIO_MAX are always output 385 */ 386 int ret = 0; 387 388 mutex_lock(&priv->mutex); 389 if (offset < TWL4030_GPIO_MAX) { 390 ret = twl4030_get_gpio_direction(offset); 391 if (ret) { 392 mutex_unlock(&priv->mutex); 393 return ret; 394 } 395 } 396 mutex_unlock(&priv->mutex); 397 398 return ret; 399 } 400 401 static int twl_to_irq(struct gpio_chip *chip, unsigned offset) 402 { 403 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); 404 405 return (priv->irq_base && (offset < TWL4030_GPIO_MAX)) 406 ? (priv->irq_base + offset) 407 : -EINVAL; 408 } 409 410 static const struct gpio_chip template_chip = { 411 .label = "twl4030", 412 .owner = THIS_MODULE, 413 .request = twl_request, 414 .free = twl_free, 415 .direction_input = twl_direction_in, 416 .direction_output = twl_direction_out, 417 .get_direction = twl_get_direction, 418 .get = twl_get, 419 .set = twl_set, 420 .to_irq = twl_to_irq, 421 .can_sleep = true, 422 }; 423 424 /*----------------------------------------------------------------------*/ 425 426 static int gpio_twl4030_pulls(u32 ups, u32 downs) 427 { 428 u8 message[5]; 429 unsigned i, gpio_bit; 430 431 /* For most pins, a pulldown was enabled by default. 432 * We should have data that's specific to this board. 433 */ 434 for (gpio_bit = 1, i = 0; i < 5; i++) { 435 u8 bit_mask; 436 unsigned j; 437 438 for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) { 439 if (ups & gpio_bit) 440 bit_mask |= 1 << (j + 1); 441 else if (downs & gpio_bit) 442 bit_mask |= 1 << (j + 0); 443 } 444 message[i] = bit_mask; 445 } 446 447 return twl_i2c_write(TWL4030_MODULE_GPIO, message, 448 REG_GPIOPUPDCTR1, 5); 449 } 450 451 static int gpio_twl4030_debounce(u32 debounce, u8 mmc_cd) 452 { 453 u8 message[3]; 454 455 /* 30 msec of debouncing is always used for MMC card detect, 456 * and is optional for everything else. 457 */ 458 message[0] = (debounce & 0xff) | (mmc_cd & 0x03); 459 debounce >>= 8; 460 message[1] = (debounce & 0xff); 461 debounce >>= 8; 462 message[2] = (debounce & 0x03); 463 464 return twl_i2c_write(TWL4030_MODULE_GPIO, message, 465 REG_GPIO_DEBEN1, 3); 466 } 467 468 static int gpio_twl4030_remove(struct platform_device *pdev); 469 470 static struct twl4030_gpio_platform_data *of_gpio_twl4030(struct device *dev, 471 struct twl4030_gpio_platform_data *pdata) 472 { 473 struct twl4030_gpio_platform_data *omap_twl_info; 474 475 omap_twl_info = devm_kzalloc(dev, sizeof(*omap_twl_info), GFP_KERNEL); 476 if (!omap_twl_info) 477 return NULL; 478 479 if (pdata) 480 *omap_twl_info = *pdata; 481 482 omap_twl_info->use_leds = of_property_read_bool(dev->of_node, 483 "ti,use-leds"); 484 485 of_property_read_u32(dev->of_node, "ti,debounce", 486 &omap_twl_info->debounce); 487 of_property_read_u32(dev->of_node, "ti,mmc-cd", 488 (u32 *)&omap_twl_info->mmc_cd); 489 of_property_read_u32(dev->of_node, "ti,pullups", 490 &omap_twl_info->pullups); 491 of_property_read_u32(dev->of_node, "ti,pulldowns", 492 &omap_twl_info->pulldowns); 493 494 return omap_twl_info; 495 } 496 497 static int gpio_twl4030_probe(struct platform_device *pdev) 498 { 499 struct twl4030_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev); 500 struct device_node *node = pdev->dev.of_node; 501 struct gpio_twl4030_priv *priv; 502 int ret, irq_base; 503 504 priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_twl4030_priv), 505 GFP_KERNEL); 506 if (!priv) 507 return -ENOMEM; 508 509 /* maybe setup IRQs */ 510 if (is_module()) { 511 dev_err(&pdev->dev, "can't dispatch IRQs from modules\n"); 512 goto no_irqs; 513 } 514 515 irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 516 0, TWL4030_GPIO_MAX, 0); 517 if (irq_base < 0) { 518 dev_err(&pdev->dev, "Failed to alloc irq_descs\n"); 519 return irq_base; 520 } 521 522 irq_domain_add_legacy(node, TWL4030_GPIO_MAX, irq_base, 0, 523 &irq_domain_simple_ops, NULL); 524 525 ret = twl4030_sih_setup(&pdev->dev, TWL4030_MODULE_GPIO, irq_base); 526 if (ret < 0) 527 return ret; 528 529 priv->irq_base = irq_base; 530 531 no_irqs: 532 priv->gpio_chip = template_chip; 533 priv->gpio_chip.base = -1; 534 priv->gpio_chip.ngpio = TWL4030_GPIO_MAX; 535 priv->gpio_chip.parent = &pdev->dev; 536 537 mutex_init(&priv->mutex); 538 539 if (node) 540 pdata = of_gpio_twl4030(&pdev->dev, pdata); 541 542 if (pdata == NULL) { 543 dev_err(&pdev->dev, "Platform data is missing\n"); 544 return -ENXIO; 545 } 546 547 /* 548 * NOTE: boards may waste power if they don't set pullups 549 * and pulldowns correctly ... default for non-ULPI pins is 550 * pulldown, and some other pins may have external pullups 551 * or pulldowns. Careful! 552 */ 553 ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns); 554 if (ret) 555 dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n", 556 pdata->pullups, pdata->pulldowns, ret); 557 558 ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd); 559 if (ret) 560 dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n", 561 pdata->debounce, pdata->mmc_cd, ret); 562 563 /* 564 * NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE, 565 * is (still) clear if use_leds is set. 566 */ 567 if (pdata->use_leds) 568 priv->gpio_chip.ngpio += 2; 569 570 ret = gpiochip_add_data(&priv->gpio_chip, priv); 571 if (ret < 0) { 572 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret); 573 priv->gpio_chip.ngpio = 0; 574 gpio_twl4030_remove(pdev); 575 goto out; 576 } 577 578 platform_set_drvdata(pdev, priv); 579 580 if (pdata->setup) { 581 int status; 582 583 status = pdata->setup(&pdev->dev, priv->gpio_chip.base, 584 TWL4030_GPIO_MAX); 585 if (status) 586 dev_dbg(&pdev->dev, "setup --> %d\n", status); 587 } 588 589 out: 590 return ret; 591 } 592 593 /* Cannot use as gpio_twl4030_probe() calls us */ 594 static int gpio_twl4030_remove(struct platform_device *pdev) 595 { 596 struct twl4030_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev); 597 struct gpio_twl4030_priv *priv = platform_get_drvdata(pdev); 598 int status; 599 600 if (pdata && pdata->teardown) { 601 status = pdata->teardown(&pdev->dev, priv->gpio_chip.base, 602 TWL4030_GPIO_MAX); 603 if (status) { 604 dev_dbg(&pdev->dev, "teardown --> %d\n", status); 605 return status; 606 } 607 } 608 609 gpiochip_remove(&priv->gpio_chip); 610 611 if (is_module()) 612 return 0; 613 614 /* REVISIT no support yet for deregistering all the IRQs */ 615 WARN_ON(1); 616 return -EIO; 617 } 618 619 static const struct of_device_id twl_gpio_match[] = { 620 { .compatible = "ti,twl4030-gpio", }, 621 { }, 622 }; 623 MODULE_DEVICE_TABLE(of, twl_gpio_match); 624 625 /* Note: this hardware lives inside an I2C-based multi-function device. */ 626 MODULE_ALIAS("platform:twl4030_gpio"); 627 628 static struct platform_driver gpio_twl4030_driver = { 629 .driver = { 630 .name = "twl4030_gpio", 631 .of_match_table = twl_gpio_match, 632 }, 633 .probe = gpio_twl4030_probe, 634 .remove = gpio_twl4030_remove, 635 }; 636 637 static int __init gpio_twl4030_init(void) 638 { 639 return platform_driver_register(&gpio_twl4030_driver); 640 } 641 subsys_initcall(gpio_twl4030_init); 642 643 static void __exit gpio_twl4030_exit(void) 644 { 645 platform_driver_unregister(&gpio_twl4030_driver); 646 } 647 module_exit(gpio_twl4030_exit); 648 649 MODULE_AUTHOR("Texas Instruments, Inc."); 650 MODULE_DESCRIPTION("GPIO interface for TWL4030"); 651 MODULE_LICENSE("GPL"); 652