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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Access to GPIOs on TWL4030/TPS659x0 chips4 *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 Menon13 */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 as31 * inputs or outputs, with pullups or pulldowns on each pin. Each32 * GPIO can trigger interrupts on either or both edges.33 *34 * GPIO interrupts can be fed to either of two IRQ lines; this is35 * 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 MODULE42#define is_module() true43#else44#define is_module() false45#endif46 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 0x0003ffff54 55struct 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 registers70 */71static 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 base80 * PWMs A and B are dedicated to LEDs A and B, respectively.81 */82 83#define TWL4030_LED_LEDEN_REG 0x0084#define TWL4030_PWMAON_REG 0x0185#define TWL4030_PWMAOFF_REG 0x0286#define TWL4030_PWMBON_REG 0x0387#define TWL4030_PWMBOFF_REG 0x0488 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 register105 */106static 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 117static u8 cached_leden;118 119/* The LED lines are open drain outputs ... a FET pulls to GND, so an120 * external pullup is needed. We could also expose the integrated PWM121 * as a LED brightness control; we initialize it as "always on".122 */123static 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 else133 cached_leden |= mask;134 135 WARN_ON_ONCE(twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,136 TWL4030_LED_LEDEN_REG));137}138 139static 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 else152 reg = ret | d_msk;153 154 ret = gpio_twl4030_write(base, reg);155 }156 return ret;157}158 159static 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 176static 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 else185 base = REG_CLEARGPIODATAOUT1 + d_bnk;186 187 return gpio_twl4030_write(base, d_msk);188}189 190static 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 207static 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_LEDAEXT217 | 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 vMMC1258 * 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 267done:268 if (!status)269 priv->usage_count |= BIT(offset);270 271 mutex_unlock(&priv->mutex);272 return status;273}274 275static 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 291out:292 mutex_unlock(&priv->mutex);293}294 295static 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 else304 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 314static 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 else329 status = twl4030_get_gpio_datain(offset);330 331 ret = (status < 0) ? status : !!status;332out:333 mutex_unlock(&priv->mutex);334 return ret;335}336 337static 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 else345 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);346 347 if (value)348 priv->out_state |= BIT(offset);349 else350 priv->out_state &= ~BIT(offset);351 352 mutex_unlock(&priv->mutex);353}354 355static 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 output371 */372 373 priv->direction |= BIT(offset);374 mutex_unlock(&priv->mutex);375 376 twl_set(chip, offset, value);377 378 return ret;379}380 381static 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_OUT386 * LED GPIOs >= TWL4030_GPIO_MAX are always output387 */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 403static 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 412static 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 428static 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 453static 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 470static 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 */494static 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 502static 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 536no_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 pullups552 * and pulldowns correctly ... default for non-ULPI pins is553 * pulldown, and some other pins may have external pullups554 * 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 power582 * 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 608static const struct of_device_id twl_gpio_match[] = {609 { .compatible = "ti,twl4030-gpio", },610 { },611};612MODULE_DEVICE_TABLE(of, twl_gpio_match);613 614/* Note: this hardware lives inside an I2C-based multi-function device. */615MODULE_ALIAS("platform:twl4030_gpio");616 617static 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 625static int __init gpio_twl4030_init(void)626{627 return platform_driver_register(&gpio_twl4030_driver);628}629subsys_initcall(gpio_twl4030_init);630 631static void __exit gpio_twl4030_exit(void)632{633 platform_driver_unregister(&gpio_twl4030_driver);634}635module_exit(gpio_twl4030_exit);636 637MODULE_AUTHOR("Texas Instruments, Inc.");638MODULE_DESCRIPTION("GPIO interface for TWL4030");639MODULE_LICENSE("GPL");640