drivers/gpio/gpio-tegra.c

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