1 /* 2 * Access to GPIOs on TWL4030/TPS659x0 chips 3 * 4 * Copyright (C) 2006-2007 Texas Instruments, Inc. 5 * Copyright (C) 2006 MontaVista Software, Inc. 6 * 7 * Code re-arranged and cleaned up by: 8 * Syed Mohammed Khasim <x0khasim@ti.com> 9 * 10 * Initial Code: 11 * Andy Lowe / Nishanth Menon 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or 16 * (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 26 */ 27 28 #include <linux/module.h> 29 #include <linux/init.h> 30 #include <linux/interrupt.h> 31 #include <linux/kthread.h> 32 #include <linux/irq.h> 33 #include <linux/gpio.h> 34 #include <linux/platform_device.h> 35 #include <linux/of.h> 36 #include <linux/irqdomain.h> 37 38 #include <linux/i2c/twl.h> 39 40 41 /* 42 * The GPIO "subchip" supports 18 GPIOs which can be configured as 43 * inputs or outputs, with pullups or pulldowns on each pin. Each 44 * GPIO can trigger interrupts on either or both edges. 45 * 46 * GPIO interrupts can be fed to either of two IRQ lines; this is 47 * intended to support multiple hosts. 48 * 49 * There are also two LED pins used sometimes as output-only GPIOs. 50 */ 51 52 53 static struct gpio_chip twl_gpiochip; 54 static int twl4030_gpio_irq_base; 55 56 /* genirq interfaces are not available to modules */ 57 #ifdef MODULE 58 #define is_module() true 59 #else 60 #define is_module() false 61 #endif 62 63 /* GPIO_CTRL Fields */ 64 #define MASK_GPIO_CTRL_GPIO0CD1 BIT(0) 65 #define MASK_GPIO_CTRL_GPIO1CD2 BIT(1) 66 #define MASK_GPIO_CTRL_GPIO_ON BIT(2) 67 68 /* Mask for GPIO registers when aggregated into a 32-bit integer */ 69 #define GPIO_32_MASK 0x0003ffff 70 71 /* Data structures */ 72 static DEFINE_MUTEX(gpio_lock); 73 74 /* store usage of each GPIO. - each bit represents one GPIO */ 75 static unsigned int gpio_usage_count; 76 77 /*----------------------------------------------------------------------*/ 78 79 /* 80 * To configure TWL4030 GPIO module registers 81 */ 82 static inline int gpio_twl4030_write(u8 address, u8 data) 83 { 84 return twl_i2c_write_u8(TWL4030_MODULE_GPIO, data, address); 85 } 86 87 /*----------------------------------------------------------------------*/ 88 89 /* 90 * LED register offsets (use TWL4030_MODULE_{LED,PWMA,PWMB})) 91 * PWMs A and B are dedicated to LEDs A and B, respectively. 92 */ 93 94 #define TWL4030_LED_LEDEN 0x0 95 96 /* LEDEN bits */ 97 #define LEDEN_LEDAON BIT(0) 98 #define LEDEN_LEDBON BIT(1) 99 #define LEDEN_LEDAEXT BIT(2) 100 #define LEDEN_LEDBEXT BIT(3) 101 #define LEDEN_LEDAPWM BIT(4) 102 #define LEDEN_LEDBPWM BIT(5) 103 #define LEDEN_PWM_LENGTHA BIT(6) 104 #define LEDEN_PWM_LENGTHB BIT(7) 105 106 #define TWL4030_PWMx_PWMxON 0x0 107 #define TWL4030_PWMx_PWMxOFF 0x1 108 109 #define PWMxON_LENGTH BIT(7) 110 111 /*----------------------------------------------------------------------*/ 112 113 /* 114 * To read a TWL4030 GPIO module register 115 */ 116 static inline int gpio_twl4030_read(u8 address) 117 { 118 u8 data; 119 int ret = 0; 120 121 ret = twl_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address); 122 return (ret < 0) ? ret : data; 123 } 124 125 /*----------------------------------------------------------------------*/ 126 127 static u8 cached_leden; /* protected by gpio_lock */ 128 129 /* The LED lines are open drain outputs ... a FET pulls to GND, so an 130 * external pullup is needed. We could also expose the integrated PWM 131 * as a LED brightness control; we initialize it as "always on". 132 */ 133 static void twl4030_led_set_value(int led, int value) 134 { 135 u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM; 136 int status; 137 138 if (led) 139 mask <<= 1; 140 141 mutex_lock(&gpio_lock); 142 if (value) 143 cached_leden &= ~mask; 144 else 145 cached_leden |= mask; 146 status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden, 147 TWL4030_LED_LEDEN); 148 mutex_unlock(&gpio_lock); 149 } 150 151 static int twl4030_set_gpio_direction(int gpio, int is_input) 152 { 153 u8 d_bnk = gpio >> 3; 154 u8 d_msk = BIT(gpio & 0x7); 155 u8 reg = 0; 156 u8 base = REG_GPIODATADIR1 + d_bnk; 157 int ret = 0; 158 159 mutex_lock(&gpio_lock); 160 ret = gpio_twl4030_read(base); 161 if (ret >= 0) { 162 if (is_input) 163 reg = ret & ~d_msk; 164 else 165 reg = ret | d_msk; 166 167 ret = gpio_twl4030_write(base, reg); 168 } 169 mutex_unlock(&gpio_lock); 170 return ret; 171 } 172 173 static int twl4030_set_gpio_dataout(int gpio, int enable) 174 { 175 u8 d_bnk = gpio >> 3; 176 u8 d_msk = BIT(gpio & 0x7); 177 u8 base = 0; 178 179 if (enable) 180 base = REG_SETGPIODATAOUT1 + d_bnk; 181 else 182 base = REG_CLEARGPIODATAOUT1 + d_bnk; 183 184 return gpio_twl4030_write(base, d_msk); 185 } 186 187 static int twl4030_get_gpio_datain(int gpio) 188 { 189 u8 d_bnk = gpio >> 3; 190 u8 d_off = gpio & 0x7; 191 u8 base = 0; 192 int ret = 0; 193 194 if (unlikely((gpio >= TWL4030_GPIO_MAX) 195 || !(gpio_usage_count & BIT(gpio)))) 196 return -EPERM; 197 198 base = REG_GPIODATAIN1 + d_bnk; 199 ret = gpio_twl4030_read(base); 200 if (ret > 0) 201 ret = (ret >> d_off) & 0x1; 202 203 return ret; 204 } 205 206 /*----------------------------------------------------------------------*/ 207 208 static int twl_request(struct gpio_chip *chip, unsigned offset) 209 { 210 int status = 0; 211 212 mutex_lock(&gpio_lock); 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 module = TWL4030_MODULE_PWMA; 219 220 offset -= TWL4030_GPIO_MAX; 221 if (offset) { 222 ledclr_mask <<= 1; 223 module = TWL4030_MODULE_PWMB; 224 } 225 226 /* initialize PWM to always-drive */ 227 status = twl_i2c_write_u8(module, 0x7f, 228 TWL4030_PWMx_PWMxOFF); 229 if (status < 0) 230 goto done; 231 status = twl_i2c_write_u8(module, 0x7f, 232 TWL4030_PWMx_PWMxON); 233 if (status < 0) 234 goto done; 235 236 /* init LED to not-driven (high) */ 237 module = TWL4030_MODULE_LED; 238 status = twl_i2c_read_u8(module, &cached_leden, 239 TWL4030_LED_LEDEN); 240 if (status < 0) 241 goto done; 242 cached_leden &= ~ledclr_mask; 243 status = twl_i2c_write_u8(module, cached_leden, 244 TWL4030_LED_LEDEN); 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 (!gpio_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 = chip->dev->platform_data; 261 if (pdata) 262 value |= pdata->mmc_cd & 0x03; 263 264 status = gpio_twl4030_write(REG_GPIO_CTRL, value); 265 } 266 267 if (!status) 268 gpio_usage_count |= (0x1 << offset); 269 270 done: 271 mutex_unlock(&gpio_lock); 272 return status; 273 } 274 275 static void twl_free(struct gpio_chip *chip, unsigned offset) 276 { 277 if (offset >= TWL4030_GPIO_MAX) { 278 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1); 279 return; 280 } 281 282 mutex_lock(&gpio_lock); 283 284 gpio_usage_count &= ~BIT(offset); 285 286 /* on last use, switch off GPIO module */ 287 if (!gpio_usage_count) 288 gpio_twl4030_write(REG_GPIO_CTRL, 0x0); 289 290 mutex_unlock(&gpio_lock); 291 } 292 293 static int twl_direction_in(struct gpio_chip *chip, unsigned offset) 294 { 295 return (offset < TWL4030_GPIO_MAX) 296 ? twl4030_set_gpio_direction(offset, 1) 297 : -EINVAL; 298 } 299 300 static int twl_get(struct gpio_chip *chip, unsigned offset) 301 { 302 int status = 0; 303 304 if (offset < TWL4030_GPIO_MAX) 305 status = twl4030_get_gpio_datain(offset); 306 else if (offset == TWL4030_GPIO_MAX) 307 status = cached_leden & LEDEN_LEDAON; 308 else 309 status = cached_leden & LEDEN_LEDBON; 310 return (status < 0) ? 0 : status; 311 } 312 313 static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value) 314 { 315 if (offset < TWL4030_GPIO_MAX) { 316 twl4030_set_gpio_dataout(offset, value); 317 return twl4030_set_gpio_direction(offset, 0); 318 } else { 319 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value); 320 return 0; 321 } 322 } 323 324 static void twl_set(struct gpio_chip *chip, unsigned offset, int value) 325 { 326 if (offset < TWL4030_GPIO_MAX) 327 twl4030_set_gpio_dataout(offset, value); 328 else 329 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value); 330 } 331 332 static int twl_to_irq(struct gpio_chip *chip, unsigned offset) 333 { 334 return (twl4030_gpio_irq_base && (offset < TWL4030_GPIO_MAX)) 335 ? (twl4030_gpio_irq_base + offset) 336 : -EINVAL; 337 } 338 339 static struct gpio_chip twl_gpiochip = { 340 .label = "twl4030", 341 .owner = THIS_MODULE, 342 .request = twl_request, 343 .free = twl_free, 344 .direction_input = twl_direction_in, 345 .get = twl_get, 346 .direction_output = twl_direction_out, 347 .set = twl_set, 348 .to_irq = twl_to_irq, 349 .can_sleep = 1, 350 }; 351 352 /*----------------------------------------------------------------------*/ 353 354 static int __devinit gpio_twl4030_pulls(u32 ups, u32 downs) 355 { 356 u8 message[6]; 357 unsigned i, gpio_bit; 358 359 /* For most pins, a pulldown was enabled by default. 360 * We should have data that's specific to this board. 361 */ 362 for (gpio_bit = 1, i = 1; i < 6; i++) { 363 u8 bit_mask; 364 unsigned j; 365 366 for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) { 367 if (ups & gpio_bit) 368 bit_mask |= 1 << (j + 1); 369 else if (downs & gpio_bit) 370 bit_mask |= 1 << (j + 0); 371 } 372 message[i] = bit_mask; 373 } 374 375 return twl_i2c_write(TWL4030_MODULE_GPIO, message, 376 REG_GPIOPUPDCTR1, 5); 377 } 378 379 static int __devinit gpio_twl4030_debounce(u32 debounce, u8 mmc_cd) 380 { 381 u8 message[4]; 382 383 /* 30 msec of debouncing is always used for MMC card detect, 384 * and is optional for everything else. 385 */ 386 message[1] = (debounce & 0xff) | (mmc_cd & 0x03); 387 debounce >>= 8; 388 message[2] = (debounce & 0xff); 389 debounce >>= 8; 390 message[3] = (debounce & 0x03); 391 392 return twl_i2c_write(TWL4030_MODULE_GPIO, message, 393 REG_GPIO_DEBEN1, 3); 394 } 395 396 static int gpio_twl4030_remove(struct platform_device *pdev); 397 398 static int __devinit gpio_twl4030_probe(struct platform_device *pdev) 399 { 400 struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data; 401 struct device_node *node = pdev->dev.of_node; 402 int ret, irq_base; 403 404 /* maybe setup IRQs */ 405 if (is_module()) { 406 dev_err(&pdev->dev, "can't dispatch IRQs from modules\n"); 407 goto no_irqs; 408 } 409 410 irq_base = irq_alloc_descs(-1, 0, TWL4030_GPIO_MAX, 0); 411 if (irq_base < 0) { 412 dev_err(&pdev->dev, "Failed to alloc irq_descs\n"); 413 return irq_base; 414 } 415 416 irq_domain_add_legacy(node, TWL4030_GPIO_MAX, irq_base, 0, 417 &irq_domain_simple_ops, NULL); 418 419 ret = twl4030_sih_setup(&pdev->dev, TWL4030_MODULE_GPIO, irq_base); 420 if (ret < 0) 421 return ret; 422 423 twl4030_gpio_irq_base = irq_base; 424 425 no_irqs: 426 twl_gpiochip.base = -1; 427 twl_gpiochip.ngpio = TWL4030_GPIO_MAX; 428 twl_gpiochip.dev = &pdev->dev; 429 430 if (pdata) { 431 twl_gpiochip.base = pdata->gpio_base; 432 433 /* 434 * NOTE: boards may waste power if they don't set pullups 435 * and pulldowns correctly ... default for non-ULPI pins is 436 * pulldown, and some other pins may have external pullups 437 * or pulldowns. Careful! 438 */ 439 ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns); 440 if (ret) 441 dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n", 442 pdata->pullups, pdata->pulldowns, 443 ret); 444 445 ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd); 446 if (ret) 447 dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n", 448 pdata->debounce, pdata->mmc_cd, 449 ret); 450 451 /* 452 * NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE, 453 * is (still) clear if use_leds is set. 454 */ 455 if (pdata->use_leds) 456 twl_gpiochip.ngpio += 2; 457 } 458 459 ret = gpiochip_add(&twl_gpiochip); 460 if (ret < 0) { 461 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret); 462 twl_gpiochip.ngpio = 0; 463 gpio_twl4030_remove(pdev); 464 } else if (pdata && pdata->setup) { 465 int status; 466 467 status = pdata->setup(&pdev->dev, 468 pdata->gpio_base, TWL4030_GPIO_MAX); 469 if (status) 470 dev_dbg(&pdev->dev, "setup --> %d\n", status); 471 } 472 473 return ret; 474 } 475 476 /* Cannot use __devexit as gpio_twl4030_probe() calls us */ 477 static int gpio_twl4030_remove(struct platform_device *pdev) 478 { 479 struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data; 480 int status; 481 482 if (pdata && pdata->teardown) { 483 status = pdata->teardown(&pdev->dev, 484 pdata->gpio_base, TWL4030_GPIO_MAX); 485 if (status) { 486 dev_dbg(&pdev->dev, "teardown --> %d\n", status); 487 return status; 488 } 489 } 490 491 status = gpiochip_remove(&twl_gpiochip); 492 if (status < 0) 493 return status; 494 495 if (is_module()) 496 return 0; 497 498 /* REVISIT no support yet for deregistering all the IRQs */ 499 WARN_ON(1); 500 return -EIO; 501 } 502 503 static const struct of_device_id twl_gpio_match[] = { 504 { .compatible = "ti,twl4030-gpio", }, 505 { }, 506 }; 507 MODULE_DEVICE_TABLE(of, twl_gpio_match); 508 509 /* Note: this hardware lives inside an I2C-based multi-function device. */ 510 MODULE_ALIAS("platform:twl4030_gpio"); 511 512 static struct platform_driver gpio_twl4030_driver = { 513 .driver = { 514 .name = "twl4030_gpio", 515 .owner = THIS_MODULE, 516 .of_match_table = of_match_ptr(twl_gpio_match), 517 }, 518 .probe = gpio_twl4030_probe, 519 .remove = gpio_twl4030_remove, 520 }; 521 522 static int __init gpio_twl4030_init(void) 523 { 524 return platform_driver_register(&gpio_twl4030_driver); 525 } 526 subsys_initcall(gpio_twl4030_init); 527 528 static void __exit gpio_twl4030_exit(void) 529 { 530 platform_driver_unregister(&gpio_twl4030_driver); 531 } 532 module_exit(gpio_twl4030_exit); 533 534 MODULE_AUTHOR("Texas Instruments, Inc."); 535 MODULE_DESCRIPTION("GPIO interface for TWL4030"); 536 MODULE_LICENSE("GPL"); 537