1/* 2 * arch/arm/mach-tegra/gpio.c 3 * 4 * Copyright (c) 2010 Google, Inc 5 * 6 * Author: 7 * Erik Gilling <konkers@google.com> 8 * 9 * This software is licensed under the terms of the GNU General Public 10 * License version 2, as published by the Free Software Foundation, and 11 * may be copied, distributed, and modified under those terms. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 */ 19 20#include <linux/err.h> 21#include <linux/init.h> 22#include <linux/irq.h> 23#include <linux/interrupt.h> 24#include <linux/io.h> 25#include <linux/gpio.h> 26#include <linux/of_device.h> 27#include <linux/platform_device.h> 28#include <linux/module.h> 29#include <linux/irqdomain.h> 30#include <linux/irqchip/chained_irq.h> 31#include <linux/pinctrl/consumer.h> 32#include <linux/pm.h> 33 34#define GPIO_BANK(x) ((x) >> 5) 35#define GPIO_PORT(x) (((x) >> 3) & 0x3) 36#define GPIO_BIT(x) ((x) & 0x7) 37 38#define GPIO_REG(x) (GPIO_BANK(x) * tegra_gpio_bank_stride + \ 39 GPIO_PORT(x) * 4) 40 41#define GPIO_CNF(x) (GPIO_REG(x) + 0x00) 42#define GPIO_OE(x) (GPIO_REG(x) + 0x10) 43#define GPIO_OUT(x) (GPIO_REG(x) + 0X20) 44#define GPIO_IN(x) (GPIO_REG(x) + 0x30) 45#define GPIO_INT_STA(x) (GPIO_REG(x) + 0x40) 46#define GPIO_INT_ENB(x) (GPIO_REG(x) + 0x50) 47#define GPIO_INT_LVL(x) (GPIO_REG(x) + 0x60) 48#define GPIO_INT_CLR(x) (GPIO_REG(x) + 0x70) 49 50#define GPIO_MSK_CNF(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x00) 51#define GPIO_MSK_OE(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x10) 52#define GPIO_MSK_OUT(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0X20) 53#define GPIO_MSK_INT_STA(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x40) 54#define GPIO_MSK_INT_ENB(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x50) 55#define GPIO_MSK_INT_LVL(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x60) 56 57#define GPIO_INT_LVL_MASK 0x010101 58#define GPIO_INT_LVL_EDGE_RISING 0x000101 59#define GPIO_INT_LVL_EDGE_FALLING 0x000100 60#define GPIO_INT_LVL_EDGE_BOTH 0x010100 61#define GPIO_INT_LVL_LEVEL_HIGH 0x000001 62#define GPIO_INT_LVL_LEVEL_LOW 0x000000 63 64struct tegra_gpio_bank { 65 int bank; 66 int irq; 67 spinlock_t lvl_lock[4]; 68#ifdef CONFIG_PM_SLEEP 69 u32 cnf[4]; 70 u32 out[4]; 71 u32 oe[4]; 72 u32 int_enb[4]; 73 u32 int_lvl[4]; 74 u32 wake_enb[4]; 75#endif 76}; 77 78static struct device *dev; 79static struct irq_domain *irq_domain; 80static void __iomem *regs; 81static u32 tegra_gpio_bank_count; 82static u32 tegra_gpio_bank_stride; 83static u32 tegra_gpio_upper_offset; 84static struct tegra_gpio_bank *tegra_gpio_banks; 85 86static inline void tegra_gpio_writel(u32 val, u32 reg) 87{ 88 __raw_writel(val, regs + reg); 89} 90 91static inline u32 tegra_gpio_readl(u32 reg) 92{ 93 return __raw_readl(regs + reg); 94} 95 96static int tegra_gpio_compose(int bank, int port, int bit) 97{ 98 return (bank << 5) | ((port & 0x3) << 3) | (bit & 0x7); 99} 100 101static void tegra_gpio_mask_write(u32 reg, int gpio, int value) 102{ 103 u32 val; 104 105 val = 0x100 << GPIO_BIT(gpio); 106 if (value) 107 val |= 1 << GPIO_BIT(gpio); 108 tegra_gpio_writel(val, reg); 109} 110 111static void tegra_gpio_enable(int gpio) 112{ 113 tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1); 114} 115 116static void tegra_gpio_disable(int gpio) 117{ 118 tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0); 119} 120 121static int tegra_gpio_request(struct gpio_chip *chip, unsigned offset) 122{ 123 return pinctrl_request_gpio(offset); 124} 125 126static void tegra_gpio_free(struct gpio_chip *chip, unsigned offset) 127{ 128 pinctrl_free_gpio(offset); 129 tegra_gpio_disable(offset); 130} 131 132static void tegra_gpio_set(struct gpio_chip *chip, unsigned offset, int value) 133{ 134 tegra_gpio_mask_write(GPIO_MSK_OUT(offset), offset, value); 135} 136 137static int tegra_gpio_get(struct gpio_chip *chip, unsigned offset) 138{ 139 /* If gpio is in output mode then read from the out value */ 140 if ((tegra_gpio_readl(GPIO_OE(offset)) >> GPIO_BIT(offset)) & 1) 141 return (tegra_gpio_readl(GPIO_OUT(offset)) >> 142 GPIO_BIT(offset)) & 0x1; 143 144 return (tegra_gpio_readl(GPIO_IN(offset)) >> GPIO_BIT(offset)) & 0x1; 145} 146 147static int tegra_gpio_direction_input(struct gpio_chip *chip, unsigned offset) 148{ 149 tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 0); 150 tegra_gpio_enable(offset); 151 return 0; 152} 153 154static int tegra_gpio_direction_output(struct gpio_chip *chip, unsigned offset, 155 int value) 156{ 157 tegra_gpio_set(chip, offset, value); 158 tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 1); 159 tegra_gpio_enable(offset); 160 return 0; 161} 162 163static int tegra_gpio_to_irq(struct gpio_chip *chip, unsigned offset) 164{ 165 return irq_find_mapping(irq_domain, offset); 166} 167 168static struct gpio_chip tegra_gpio_chip = { 169 .label = "tegra-gpio", 170 .request = tegra_gpio_request, 171 .free = tegra_gpio_free, 172 .direction_input = tegra_gpio_direction_input, 173 .get = tegra_gpio_get, 174 .direction_output = tegra_gpio_direction_output, 175 .set = tegra_gpio_set, 176 .to_irq = tegra_gpio_to_irq, 177 .base = 0, 178}; 179 180static void tegra_gpio_irq_ack(struct irq_data *d) 181{ 182 int gpio = d->hwirq; 183 184 tegra_gpio_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio)); 185} 186 187static void tegra_gpio_irq_mask(struct irq_data *d) 188{ 189 int gpio = d->hwirq; 190 191 tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0); 192} 193 194static void tegra_gpio_irq_unmask(struct irq_data *d) 195{ 196 int gpio = d->hwirq; 197 198 tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 1); 199} 200 201static int tegra_gpio_irq_set_type(struct irq_data *d, unsigned int type) 202{ 203 int gpio = d->hwirq; 204 struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d); 205 int port = GPIO_PORT(gpio); 206 int lvl_type; 207 int val; 208 unsigned long flags; 209 int ret; 210 211 switch (type & IRQ_TYPE_SENSE_MASK) { 212 case IRQ_TYPE_EDGE_RISING: 213 lvl_type = GPIO_INT_LVL_EDGE_RISING; 214 break; 215 216 case IRQ_TYPE_EDGE_FALLING: 217 lvl_type = GPIO_INT_LVL_EDGE_FALLING; 218 break; 219 220 case IRQ_TYPE_EDGE_BOTH: 221 lvl_type = GPIO_INT_LVL_EDGE_BOTH; 222 break; 223 224 case IRQ_TYPE_LEVEL_HIGH: 225 lvl_type = GPIO_INT_LVL_LEVEL_HIGH; 226 break; 227 228 case IRQ_TYPE_LEVEL_LOW: 229 lvl_type = GPIO_INT_LVL_LEVEL_LOW; 230 break; 231 232 default: 233 return -EINVAL; 234 } 235 236 ret = gpiochip_lock_as_irq(&tegra_gpio_chip, gpio); 237 if (ret) { 238 dev_err(dev, "unable to lock Tegra GPIO %d as IRQ\n", gpio); 239 return ret; 240 } 241 242 spin_lock_irqsave(&bank->lvl_lock[port], flags); 243 244 val = tegra_gpio_readl(GPIO_INT_LVL(gpio)); 245 val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio)); 246 val |= lvl_type << GPIO_BIT(gpio); 247 tegra_gpio_writel(val, GPIO_INT_LVL(gpio)); 248 249 spin_unlock_irqrestore(&bank->lvl_lock[port], flags); 250 251 tegra_gpio_mask_write(GPIO_MSK_OE(gpio), gpio, 0); 252 tegra_gpio_enable(gpio); 253 254 if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) 255 irq_set_handler_locked(d, handle_level_irq); 256 else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) 257 irq_set_handler_locked(d, handle_edge_irq); 258 259 return 0; 260} 261 262static void tegra_gpio_irq_shutdown(struct irq_data *d) 263{ 264 int gpio = d->hwirq; 265 266 gpiochip_unlock_as_irq(&tegra_gpio_chip, gpio); 267} 268 269static void tegra_gpio_irq_handler(struct irq_desc *desc) 270{ 271 int port; 272 int pin; 273 int unmasked = 0; 274 struct irq_chip *chip = irq_desc_get_chip(desc); 275 struct tegra_gpio_bank *bank = irq_desc_get_handler_data(desc); 276 277 chained_irq_enter(chip, desc); 278 279 for (port = 0; port < 4; port++) { 280 int gpio = tegra_gpio_compose(bank->bank, port, 0); 281 unsigned long sta = tegra_gpio_readl(GPIO_INT_STA(gpio)) & 282 tegra_gpio_readl(GPIO_INT_ENB(gpio)); 283 u32 lvl = tegra_gpio_readl(GPIO_INT_LVL(gpio)); 284 285 for_each_set_bit(pin, &sta, 8) { 286 tegra_gpio_writel(1 << pin, GPIO_INT_CLR(gpio)); 287 288 /* if gpio is edge triggered, clear condition 289 * before executing the handler so that we don't 290 * miss edges 291 */ 292 if (lvl & (0x100 << pin)) { 293 unmasked = 1; 294 chained_irq_exit(chip, desc); 295 } 296 297 generic_handle_irq(gpio_to_irq(gpio + pin)); 298 } 299 } 300 301 if (!unmasked) 302 chained_irq_exit(chip, desc); 303 304} 305 306#ifdef CONFIG_PM_SLEEP 307static int tegra_gpio_resume(struct device *dev) 308{ 309 unsigned long flags; 310 int b; 311 int p; 312 313 local_irq_save(flags); 314 315 for (b = 0; b < tegra_gpio_bank_count; b++) { 316 struct tegra_gpio_bank *bank = &tegra_gpio_banks[b]; 317 318 for (p = 0; p < ARRAY_SIZE(bank->oe); p++) { 319 unsigned int gpio = (b<<5) | (p<<3); 320 tegra_gpio_writel(bank->cnf[p], GPIO_CNF(gpio)); 321 tegra_gpio_writel(bank->out[p], GPIO_OUT(gpio)); 322 tegra_gpio_writel(bank->oe[p], GPIO_OE(gpio)); 323 tegra_gpio_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio)); 324 tegra_gpio_writel(bank->int_enb[p], GPIO_INT_ENB(gpio)); 325 } 326 } 327 328 local_irq_restore(flags); 329 return 0; 330} 331 332static int tegra_gpio_suspend(struct device *dev) 333{ 334 unsigned long flags; 335 int b; 336 int p; 337 338 local_irq_save(flags); 339 for (b = 0; b < tegra_gpio_bank_count; b++) { 340 struct tegra_gpio_bank *bank = &tegra_gpio_banks[b]; 341 342 for (p = 0; p < ARRAY_SIZE(bank->oe); p++) { 343 unsigned int gpio = (b<<5) | (p<<3); 344 bank->cnf[p] = tegra_gpio_readl(GPIO_CNF(gpio)); 345 bank->out[p] = tegra_gpio_readl(GPIO_OUT(gpio)); 346 bank->oe[p] = tegra_gpio_readl(GPIO_OE(gpio)); 347 bank->int_enb[p] = tegra_gpio_readl(GPIO_INT_ENB(gpio)); 348 bank->int_lvl[p] = tegra_gpio_readl(GPIO_INT_LVL(gpio)); 349 350 /* Enable gpio irq for wake up source */ 351 tegra_gpio_writel(bank->wake_enb[p], 352 GPIO_INT_ENB(gpio)); 353 } 354 } 355 local_irq_restore(flags); 356 return 0; 357} 358 359static int tegra_gpio_irq_set_wake(struct irq_data *d, unsigned int enable) 360{ 361 struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d); 362 int gpio = d->hwirq; 363 u32 port, bit, mask; 364 365 port = GPIO_PORT(gpio); 366 bit = GPIO_BIT(gpio); 367 mask = BIT(bit); 368 369 if (enable) 370 bank->wake_enb[port] |= mask; 371 else 372 bank->wake_enb[port] &= ~mask; 373 374 return irq_set_irq_wake(bank->irq, enable); 375} 376#endif 377 378#ifdef CONFIG_DEBUG_FS 379 380#include <linux/debugfs.h> 381#include <linux/seq_file.h> 382 383static int dbg_gpio_show(struct seq_file *s, void *unused) 384{ 385 int i; 386 int j; 387 388 for (i = 0; i < tegra_gpio_bank_count; i++) { 389 for (j = 0; j < 4; j++) { 390 int gpio = tegra_gpio_compose(i, j, 0); 391 seq_printf(s, 392 "%d:%d %02x %02x %02x %02x %02x %02x %06x\n", 393 i, j, 394 tegra_gpio_readl(GPIO_CNF(gpio)), 395 tegra_gpio_readl(GPIO_OE(gpio)), 396 tegra_gpio_readl(GPIO_OUT(gpio)), 397 tegra_gpio_readl(GPIO_IN(gpio)), 398 tegra_gpio_readl(GPIO_INT_STA(gpio)), 399 tegra_gpio_readl(GPIO_INT_ENB(gpio)), 400 tegra_gpio_readl(GPIO_INT_LVL(gpio))); 401 } 402 } 403 return 0; 404} 405 406static int dbg_gpio_open(struct inode *inode, struct file *file) 407{ 408 return single_open(file, dbg_gpio_show, &inode->i_private); 409} 410 411static const struct file_operations debug_fops = { 412 .open = dbg_gpio_open, 413 .read = seq_read, 414 .llseek = seq_lseek, 415 .release = single_release, 416}; 417 418static void tegra_gpio_debuginit(void) 419{ 420 (void) debugfs_create_file("tegra_gpio", S_IRUGO, 421 NULL, NULL, &debug_fops); 422} 423 424#else 425 426static inline void tegra_gpio_debuginit(void) 427{ 428} 429 430#endif 431 432static struct irq_chip tegra_gpio_irq_chip = { 433 .name = "GPIO", 434 .irq_ack = tegra_gpio_irq_ack, 435 .irq_mask = tegra_gpio_irq_mask, 436 .irq_unmask = tegra_gpio_irq_unmask, 437 .irq_set_type = tegra_gpio_irq_set_type, 438 .irq_shutdown = tegra_gpio_irq_shutdown, 439#ifdef CONFIG_PM_SLEEP 440 .irq_set_wake = tegra_gpio_irq_set_wake, 441#endif 442}; 443 444static const struct dev_pm_ops tegra_gpio_pm_ops = { 445 SET_SYSTEM_SLEEP_PM_OPS(tegra_gpio_suspend, tegra_gpio_resume) 446}; 447 448struct tegra_gpio_soc_config { 449 u32 bank_stride; 450 u32 upper_offset; 451}; 452 453static struct tegra_gpio_soc_config tegra20_gpio_config = { 454 .bank_stride = 0x80, 455 .upper_offset = 0x800, 456}; 457 458static struct tegra_gpio_soc_config tegra30_gpio_config = { 459 .bank_stride = 0x100, 460 .upper_offset = 0x80, 461}; 462 463static const struct of_device_id tegra_gpio_of_match[] = { 464 { .compatible = "nvidia,tegra30-gpio", .data = &tegra30_gpio_config }, 465 { .compatible = "nvidia,tegra20-gpio", .data = &tegra20_gpio_config }, 466 { }, 467}; 468 469/* This lock class tells lockdep that GPIO irqs are in a different 470 * category than their parents, so it won't report false recursion. 471 */ 472static struct lock_class_key gpio_lock_class; 473 474static int tegra_gpio_probe(struct platform_device *pdev) 475{ 476 const struct of_device_id *match; 477 struct tegra_gpio_soc_config *config; 478 struct resource *res; 479 struct tegra_gpio_bank *bank; 480 int ret; 481 int gpio; 482 int i; 483 int j; 484 485 dev = &pdev->dev; 486 487 match = of_match_device(tegra_gpio_of_match, &pdev->dev); 488 if (!match) { 489 dev_err(&pdev->dev, "Error: No device match found\n"); 490 return -ENODEV; 491 } 492 config = (struct tegra_gpio_soc_config *)match->data; 493 494 tegra_gpio_bank_stride = config->bank_stride; 495 tegra_gpio_upper_offset = config->upper_offset; 496 497 for (;;) { 498 res = platform_get_resource(pdev, IORESOURCE_IRQ, tegra_gpio_bank_count); 499 if (!res) 500 break; 501 tegra_gpio_bank_count++; 502 } 503 if (!tegra_gpio_bank_count) { 504 dev_err(&pdev->dev, "Missing IRQ resource\n"); 505 return -ENODEV; 506 } 507 508 tegra_gpio_chip.ngpio = tegra_gpio_bank_count * 32; 509 510 tegra_gpio_banks = devm_kzalloc(&pdev->dev, 511 tegra_gpio_bank_count * sizeof(*tegra_gpio_banks), 512 GFP_KERNEL); 513 if (!tegra_gpio_banks) 514 return -ENODEV; 515 516 irq_domain = irq_domain_add_linear(pdev->dev.of_node, 517 tegra_gpio_chip.ngpio, 518 &irq_domain_simple_ops, NULL); 519 if (!irq_domain) 520 return -ENODEV; 521 522 for (i = 0; i < tegra_gpio_bank_count; i++) { 523 res = platform_get_resource(pdev, IORESOURCE_IRQ, i); 524 if (!res) { 525 dev_err(&pdev->dev, "Missing IRQ resource\n"); 526 return -ENODEV; 527 } 528 529 bank = &tegra_gpio_banks[i]; 530 bank->bank = i; 531 bank->irq = res->start; 532 } 533 534 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 535 regs = devm_ioremap_resource(&pdev->dev, res); 536 if (IS_ERR(regs)) 537 return PTR_ERR(regs); 538 539 for (i = 0; i < tegra_gpio_bank_count; i++) { 540 for (j = 0; j < 4; j++) { 541 int gpio = tegra_gpio_compose(i, j, 0); 542 tegra_gpio_writel(0x00, GPIO_INT_ENB(gpio)); 543 } 544 } 545 546 tegra_gpio_chip.of_node = pdev->dev.of_node; 547 548 ret = gpiochip_add(&tegra_gpio_chip); 549 if (ret < 0) { 550 irq_domain_remove(irq_domain); 551 return ret; 552 } 553 554 for (gpio = 0; gpio < tegra_gpio_chip.ngpio; gpio++) { 555 int irq = irq_create_mapping(irq_domain, gpio); 556 /* No validity check; all Tegra GPIOs are valid IRQs */ 557 558 bank = &tegra_gpio_banks[GPIO_BANK(gpio)]; 559 560 irq_set_lockdep_class(irq, &gpio_lock_class); 561 irq_set_chip_data(irq, bank); 562 irq_set_chip_and_handler(irq, &tegra_gpio_irq_chip, 563 handle_simple_irq); 564 } 565 566 for (i = 0; i < tegra_gpio_bank_count; i++) { 567 bank = &tegra_gpio_banks[i]; 568 569 irq_set_chained_handler_and_data(bank->irq, 570 tegra_gpio_irq_handler, bank); 571 572 for (j = 0; j < 4; j++) 573 spin_lock_init(&bank->lvl_lock[j]); 574 } 575 576 tegra_gpio_debuginit(); 577 578 return 0; 579} 580 581static struct platform_driver tegra_gpio_driver = { 582 .driver = { 583 .name = "tegra-gpio", 584 .pm = &tegra_gpio_pm_ops, 585 .of_match_table = tegra_gpio_of_match, 586 }, 587 .probe = tegra_gpio_probe, 588}; 589 590static int __init tegra_gpio_init(void) 591{ 592 return platform_driver_register(&tegra_gpio_driver); 593} 594postcore_initcall(tegra_gpio_init); 595