drivers/gpio/gpio-vr41xx.c

   1 /*
   2  *  Driver for NEC VR4100 series General-purpose I/O Unit.
   3  *
   4  *  Copyright (C) 2002 MontaVista Software Inc.
   5  *      Author: Yoichi Yuasa <source@mvista.com>
   6  *  Copyright (C) 2003-2009  Yoichi Yuasa <yuasa@linux-mips.org>
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  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  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22 #include <linux/errno.h>
  23 #include <linux/fs.h>
  24 #include <linux/gpio.h>
  25 #include <linux/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/io.h>
  28 #include <linux/irq.h>
  29 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/platform_device.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/types.h>
  34
  35 #include <asm/vr41xx/giu.h>
  36 #include <asm/vr41xx/irq.h>
  37 #include <asm/vr41xx/vr41xx.h>
  38
  39 MODULE_AUTHOR("Yoichi Yuasa <yuasa@linux-mips.org>");
  40 MODULE_DESCRIPTION("NEC VR4100 series General-purpose I/O Unit driver");
  41 MODULE_LICENSE("GPL");
  42
  43 #define GIUIOSELL       0x00
  44 #define GIUIOSELH       0x02
  45 #define GIUPIODL        0x04
  46 #define GIUPIODH        0x06
  47 #define GIUINTSTATL     0x08
  48 #define GIUINTSTATH     0x0a
  49 #define GIUINTENL       0x0c
  50 #define GIUINTENH       0x0e
  51 #define GIUINTTYPL      0x10
  52 #define GIUINTTYPH      0x12
  53 #define GIUINTALSELL    0x14
  54 #define GIUINTALSELH    0x16
  55 #define GIUINTHTSELL    0x18
  56 #define GIUINTHTSELH    0x1a
  57 #define GIUPODATL       0x1c
  58 #define GIUPODATEN      0x1c
  59 #define GIUPODATH       0x1e
  60  #define PIOEN0         0x0100
  61  #define PIOEN1         0x0200
  62 #define GIUPODAT        0x1e
  63 #define GIUFEDGEINHL    0x20
  64 #define GIUFEDGEINHH    0x22
  65 #define GIUREDGEINHL    0x24
  66 #define GIUREDGEINHH    0x26
  67
  68 #define GIUUSEUPDN      0x1e0
  69 #define GIUTERMUPDN     0x1e2
  70
  71 #define GPIO_HAS_PULLUPDOWN_IO          0x0001
  72 #define GPIO_HAS_OUTPUT_ENABLE          0x0002
  73 #define GPIO_HAS_INTERRUPT_EDGE_SELECT  0x0100
  74
  75 enum {
  76         GPIO_INPUT,
  77         GPIO_OUTPUT,
  78 };
  79
  80 static DEFINE_SPINLOCK(giu_lock);
  81 static unsigned long giu_flags;
  82
  83 static void __iomem *giu_base;
  84 static struct gpio_chip vr41xx_gpio_chip;
  85
  86 #define giu_read(offset)                readw(giu_base + (offset))
  87 #define giu_write(offset, value)        writew((value), giu_base + (offset))
  88
  89 #define GPIO_PIN_OF_IRQ(irq)    ((irq) - GIU_IRQ_BASE)
  90 #define GIUINT_HIGH_OFFSET      16
  91 #define GIUINT_HIGH_MAX         32
  92
  93 static inline u16 giu_set(u16 offset, u16 set)
  94 {
  95         u16 data;
  96
  97         data = giu_read(offset);
  98         data |= set;
  99         giu_write(offset, data);
 100
 101         return data;
 102 }
 103
 104 static inline u16 giu_clear(u16 offset, u16 clear)
 105 {
 106         u16 data;
 107
 108         data = giu_read(offset);
 109         data &= ~clear;
 110         giu_write(offset, data);
 111
 112         return data;
 113 }
 114
 115 static void ack_giuint_low(struct irq_data *d)
 116 {
 117         giu_write(GIUINTSTATL, 1 << GPIO_PIN_OF_IRQ(d->irq));
 118 }
 119
 120 static void mask_giuint_low(struct irq_data *d)
 121 {
 122         giu_clear(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(d->irq));
 123 }
 124
 125 static void mask_ack_giuint_low(struct irq_data *d)
 126 {
 127         unsigned int pin;
 128
 129         pin = GPIO_PIN_OF_IRQ(d->irq);
 130         giu_clear(GIUINTENL, 1 << pin);
 131         giu_write(GIUINTSTATL, 1 << pin);
 132 }
 133
 134 static void unmask_giuint_low(struct irq_data *d)
 135 {
 136         giu_set(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(d->irq));
 137 }
 138
 139 static unsigned int startup_giuint(struct irq_data *data)
 140 {
 141         if (gpiochip_lock_as_irq(&vr41xx_gpio_chip, data->hwirq))
 142                 dev_err(vr41xx_gpio_chip.dev,
 143                         "unable to lock HW IRQ %lu for IRQ\n",
 144                         data->hwirq);
 145         /* Satisfy the .enable semantics by unmasking the line */
 146         unmask_giuint_low(data);
 147         return 0;
 148 }
 149
 150 static void shutdown_giuint(struct irq_data *data)
 151 {
 152         mask_giuint_low(data);
 153         gpiochip_unlock_as_irq(&vr41xx_gpio_chip, data->hwirq);
 154 }
 155
 156 static struct irq_chip giuint_low_irq_chip = {
 157         .name           = "GIUINTL",
 158         .irq_ack        = ack_giuint_low,
 159         .irq_mask       = mask_giuint_low,
 160         .irq_mask_ack   = mask_ack_giuint_low,
 161         .irq_unmask     = unmask_giuint_low,
 162         .irq_startup    = startup_giuint,
 163         .irq_shutdown   = shutdown_giuint,
 164 };
 165
 166 static void ack_giuint_high(struct irq_data *d)
 167 {
 168         giu_write(GIUINTSTATH,
 169                   1 << (GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET));
 170 }
 171
 172 static void mask_giuint_high(struct irq_data *d)
 173 {
 174         giu_clear(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET));
 175 }
 176
 177 static void mask_ack_giuint_high(struct irq_data *d)
 178 {
 179         unsigned int pin;
 180
 181         pin = GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET;
 182         giu_clear(GIUINTENH, 1 << pin);
 183         giu_write(GIUINTSTATH, 1 << pin);
 184 }
 185
 186 static void unmask_giuint_high(struct irq_data *d)
 187 {
 188         giu_set(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(d->irq) - GIUINT_HIGH_OFFSET));
 189 }
 190
 191 static struct irq_chip giuint_high_irq_chip = {
 192         .name           = "GIUINTH",
 193         .irq_ack        = ack_giuint_high,
 194         .irq_mask       = mask_giuint_high,
 195         .irq_mask_ack   = mask_ack_giuint_high,
 196         .irq_unmask     = unmask_giuint_high,
 197 };
 198
 199 static int giu_get_irq(unsigned int irq)
 200 {
 201         u16 pendl, pendh, maskl, maskh;
 202         int i;
 203
 204         pendl = giu_read(GIUINTSTATL);
 205         pendh = giu_read(GIUINTSTATH);
 206         maskl = giu_read(GIUINTENL);
 207         maskh = giu_read(GIUINTENH);
 208
 209         maskl &= pendl;
 210         maskh &= pendh;
 211
 212         if (maskl) {
 213                 for (i = 0; i < 16; i++) {
 214                         if (maskl & (1 << i))
 215                                 return GIU_IRQ(i);
 216                 }
 217         } else if (maskh) {
 218                 for (i = 0; i < 16; i++) {
 219                         if (maskh & (1 << i))
 220                                 return GIU_IRQ(i + GIUINT_HIGH_OFFSET);
 221                 }
 222         }
 223
 224         printk(KERN_ERR "spurious GIU interrupt: %04x(%04x),%04x(%04x)\n",
 225                maskl, pendl, maskh, pendh);
 226
 227         atomic_inc(&irq_err_count);
 228
 229         return -EINVAL;
 230 }
 231
 232 void vr41xx_set_irq_trigger(unsigned int pin, irq_trigger_t trigger,
 233                             irq_signal_t signal)
 234 {
 235         u16 mask;
 236
 237         if (pin < GIUINT_HIGH_OFFSET) {
 238                 mask = 1 << pin;
 239                 if (trigger != IRQ_TRIGGER_LEVEL) {
 240                         giu_set(GIUINTTYPL, mask);
 241                         if (signal == IRQ_SIGNAL_HOLD)
 242                                 giu_set(GIUINTHTSELL, mask);
 243                         else
 244                                 giu_clear(GIUINTHTSELL, mask);
 245                         if (giu_flags & GPIO_HAS_INTERRUPT_EDGE_SELECT) {
 246                                 switch (trigger) {
 247                                 case IRQ_TRIGGER_EDGE_FALLING:
 248                                         giu_set(GIUFEDGEINHL, mask);
 249                                         giu_clear(GIUREDGEINHL, mask);
 250                                         break;
 251                                 case IRQ_TRIGGER_EDGE_RISING:
 252                                         giu_clear(GIUFEDGEINHL, mask);
 253                                         giu_set(GIUREDGEINHL, mask);
 254                                         break;
 255                                 default:
 256                                         giu_set(GIUFEDGEINHL, mask);
 257                                         giu_set(GIUREDGEINHL, mask);
 258                                         break;
 259                                 }
 260                         }
 261                         irq_set_chip_and_handler(GIU_IRQ(pin),
 262                                                  &giuint_low_irq_chip,
 263                                                  handle_edge_irq);
 264                 } else {
 265                         giu_clear(GIUINTTYPL, mask);
 266                         giu_clear(GIUINTHTSELL, mask);
 267                         irq_set_chip_and_handler(GIU_IRQ(pin),
 268                                                  &giuint_low_irq_chip,
 269                                                  handle_level_irq);
 270                 }
 271                 giu_write(GIUINTSTATL, mask);
 272         } else if (pin < GIUINT_HIGH_MAX) {
 273                 mask = 1 << (pin - GIUINT_HIGH_OFFSET);
 274                 if (trigger != IRQ_TRIGGER_LEVEL) {
 275                         giu_set(GIUINTTYPH, mask);
 276                         if (signal == IRQ_SIGNAL_HOLD)
 277                                 giu_set(GIUINTHTSELH, mask);
 278                         else
 279                                 giu_clear(GIUINTHTSELH, mask);
 280                         if (giu_flags & GPIO_HAS_INTERRUPT_EDGE_SELECT) {
 281                                 switch (trigger) {
 282                                 case IRQ_TRIGGER_EDGE_FALLING:
 283                                         giu_set(GIUFEDGEINHH, mask);
 284                                         giu_clear(GIUREDGEINHH, mask);
 285                                         break;
 286                                 case IRQ_TRIGGER_EDGE_RISING:
 287                                         giu_clear(GIUFEDGEINHH, mask);
 288                                         giu_set(GIUREDGEINHH, mask);
 289                                         break;
 290                                 default:
 291                                         giu_set(GIUFEDGEINHH, mask);
 292                                         giu_set(GIUREDGEINHH, mask);
 293                                         break;
 294                                 }
 295                         }
 296                         irq_set_chip_and_handler(GIU_IRQ(pin),
 297                                                  &giuint_high_irq_chip,
 298                                                  handle_edge_irq);
 299                 } else {
 300                         giu_clear(GIUINTTYPH, mask);
 301                         giu_clear(GIUINTHTSELH, mask);
 302                         irq_set_chip_and_handler(GIU_IRQ(pin),
 303                                                  &giuint_high_irq_chip,
 304                                                  handle_level_irq);
 305                 }
 306                 giu_write(GIUINTSTATH, mask);
 307         }
 308 }
 309 EXPORT_SYMBOL_GPL(vr41xx_set_irq_trigger);
 310
 311 void vr41xx_set_irq_level(unsigned int pin, irq_level_t level)
 312 {
 313         u16 mask;
 314
 315         if (pin < GIUINT_HIGH_OFFSET) {
 316                 mask = 1 << pin;
 317                 if (level == IRQ_LEVEL_HIGH)
 318                         giu_set(GIUINTALSELL, mask);
 319                 else
 320                         giu_clear(GIUINTALSELL, mask);
 321                 giu_write(GIUINTSTATL, mask);
 322         } else if (pin < GIUINT_HIGH_MAX) {
 323                 mask = 1 << (pin - GIUINT_HIGH_OFFSET);
 324                 if (level == IRQ_LEVEL_HIGH)
 325                         giu_set(GIUINTALSELH, mask);
 326                 else
 327                         giu_clear(GIUINTALSELH, mask);
 328                 giu_write(GIUINTSTATH, mask);
 329         }
 330 }
 331 EXPORT_SYMBOL_GPL(vr41xx_set_irq_level);
 332
 333 static int giu_set_direction(struct gpio_chip *chip, unsigned pin, int dir)
 334 {
 335         u16 offset, mask, reg;
 336         unsigned long flags;
 337
 338         if (pin >= chip->ngpio)
 339                 return -EINVAL;
 340
 341         if (pin < 16) {
 342                 offset = GIUIOSELL;
 343                 mask = 1 << pin;
 344         } else if (pin < 32) {
 345                 offset = GIUIOSELH;
 346                 mask = 1 << (pin - 16);
 347         } else {
 348                 if (giu_flags & GPIO_HAS_OUTPUT_ENABLE) {
 349                         offset = GIUPODATEN;
 350                         mask = 1 << (pin - 32);
 351                 } else {
 352                         switch (pin) {
 353                         case 48:
 354                                 offset = GIUPODATH;
 355                                 mask = PIOEN0;
 356                                 break;
 357                         case 49:
 358                                 offset = GIUPODATH;
 359                                 mask = PIOEN1;
 360                                 break;
 361                         default:
 362                                 return -EINVAL;
 363                         }
 364                 }
 365         }
 366
 367         spin_lock_irqsave(&giu_lock, flags);
 368
 369         reg = giu_read(offset);
 370         if (dir == GPIO_OUTPUT)
 371                 reg |= mask;
 372         else
 373                 reg &= ~mask;
 374         giu_write(offset, reg);
 375
 376         spin_unlock_irqrestore(&giu_lock, flags);
 377
 378         return 0;
 379 }
 380
 381 int vr41xx_gpio_pullupdown(unsigned int pin, gpio_pull_t pull)
 382 {
 383         u16 reg, mask;
 384         unsigned long flags;
 385
 386         if ((giu_flags & GPIO_HAS_PULLUPDOWN_IO) != GPIO_HAS_PULLUPDOWN_IO)
 387                 return -EPERM;
 388
 389         if (pin >= 15)
 390                 return -EINVAL;
 391
 392         mask = 1 << pin;
 393
 394         spin_lock_irqsave(&giu_lock, flags);
 395
 396         if (pull == GPIO_PULL_UP || pull == GPIO_PULL_DOWN) {
 397                 reg = giu_read(GIUTERMUPDN);
 398                 if (pull == GPIO_PULL_UP)
 399                         reg |= mask;
 400                 else
 401                         reg &= ~mask;
 402                 giu_write(GIUTERMUPDN, reg);
 403
 404                 reg = giu_read(GIUUSEUPDN);
 405                 reg |= mask;
 406                 giu_write(GIUUSEUPDN, reg);
 407         } else {
 408                 reg = giu_read(GIUUSEUPDN);
 409                 reg &= ~mask;
 410                 giu_write(GIUUSEUPDN, reg);
 411         }
 412
 413         spin_unlock_irqrestore(&giu_lock, flags);
 414
 415         return 0;
 416 }
 417 EXPORT_SYMBOL_GPL(vr41xx_gpio_pullupdown);
 418
 419 static int vr41xx_gpio_get(struct gpio_chip *chip, unsigned pin)
 420 {
 421         u16 reg, mask;
 422
 423         if (pin >= chip->ngpio)
 424                 return -EINVAL;
 425
 426         if (pin < 16) {
 427                 reg = giu_read(GIUPIODL);
 428                 mask = 1 << pin;
 429         } else if (pin < 32) {
 430                 reg = giu_read(GIUPIODH);
 431                 mask = 1 << (pin - 16);
 432         } else if (pin < 48) {
 433                 reg = giu_read(GIUPODATL);
 434                 mask = 1 << (pin - 32);
 435         } else {
 436                 reg = giu_read(GIUPODATH);
 437                 mask = 1 << (pin - 48);
 438         }
 439
 440         if (reg & mask)
 441                 return 1;
 442
 443         return 0;
 444 }
 445
 446 static void vr41xx_gpio_set(struct gpio_chip *chip, unsigned pin,
 447                             int value)
 448 {
 449         u16 offset, mask, reg;
 450         unsigned long flags;
 451
 452         if (pin >= chip->ngpio)
 453                 return;
 454
 455         if (pin < 16) {
 456                 offset = GIUPIODL;
 457                 mask = 1 << pin;
 458         } else if (pin < 32) {
 459                 offset = GIUPIODH;
 460                 mask = 1 << (pin - 16);
 461         } else if (pin < 48) {
 462                 offset = GIUPODATL;
 463                 mask = 1 << (pin - 32);
 464         } else {
 465                 offset = GIUPODATH;
 466                 mask = 1 << (pin - 48);
 467         }
 468
 469         spin_lock_irqsave(&giu_lock, flags);
 470
 471         reg = giu_read(offset);
 472         if (value)
 473                 reg |= mask;
 474         else
 475                 reg &= ~mask;
 476         giu_write(offset, reg);
 477
 478         spin_unlock_irqrestore(&giu_lock, flags);
 479 }
 480
 481
 482 static int vr41xx_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 483 {
 484         return giu_set_direction(chip, offset, GPIO_INPUT);
 485 }
 486
 487 static int vr41xx_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 488                                 int value)
 489 {
 490         vr41xx_gpio_set(chip, offset, value);
 491
 492         return giu_set_direction(chip, offset, GPIO_OUTPUT);
 493 }
 494
 495 static int vr41xx_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 496 {
 497         if (offset >= chip->ngpio)
 498                 return -EINVAL;
 499
 500         return GIU_IRQ_BASE + offset;
 501 }
 502
 503 static struct gpio_chip vr41xx_gpio_chip = {
 504         .label                  = "vr41xx",
 505         .owner                  = THIS_MODULE,
 506         .direction_input        = vr41xx_gpio_direction_input,
 507         .get                    = vr41xx_gpio_get,
 508         .direction_output       = vr41xx_gpio_direction_output,
 509         .set                    = vr41xx_gpio_set,
 510         .to_irq                 = vr41xx_gpio_to_irq,
 511 };
 512
 513 static int giu_probe(struct platform_device *pdev)
 514 {
 515         struct resource *res;
 516         unsigned int trigger, i, pin;
 517         struct irq_chip *chip;
 518         int irq, ret;
 519
 520         switch (pdev->id) {
 521         case GPIO_50PINS_PULLUPDOWN:
 522                 giu_flags = GPIO_HAS_PULLUPDOWN_IO;
 523                 vr41xx_gpio_chip.ngpio = 50;
 524                 break;
 525         case GPIO_36PINS:
 526                 vr41xx_gpio_chip.ngpio = 36;
 527                 break;
 528         case GPIO_48PINS_EDGE_SELECT:
 529                 giu_flags = GPIO_HAS_INTERRUPT_EDGE_SELECT;
 530                 vr41xx_gpio_chip.ngpio = 48;
 531                 break;
 532         default:
 533                 dev_err(&pdev->dev, "GIU: unknown ID %d\n", pdev->id);
 534                 return -ENODEV;
 535         }
 536
 537         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 538         if (!res)
 539                 return -EBUSY;
 540
 541         giu_base = ioremap(res->start, resource_size(res));
 542         if (!giu_base)
 543                 return -ENOMEM;
 544
 545         vr41xx_gpio_chip.dev = &pdev->dev;
 546
 547         ret = gpiochip_add(&vr41xx_gpio_chip);
 548         if (!ret) {
 549                 iounmap(giu_base);
 550                 return -ENODEV;
 551         }
 552
 553         giu_write(GIUINTENL, 0);
 554         giu_write(GIUINTENH, 0);
 555
 556         trigger = giu_read(GIUINTTYPH) << 16;
 557         trigger |= giu_read(GIUINTTYPL);
 558         for (i = GIU_IRQ_BASE; i <= GIU_IRQ_LAST; i++) {
 559                 pin = GPIO_PIN_OF_IRQ(i);
 560                 if (pin < GIUINT_HIGH_OFFSET)
 561                         chip = &giuint_low_irq_chip;
 562                 else
 563                         chip = &giuint_high_irq_chip;
 564
 565                 if (trigger & (1 << pin))
 566                         irq_set_chip_and_handler(i, chip, handle_edge_irq);
 567                 else
 568                         irq_set_chip_and_handler(i, chip, handle_level_irq);
 569
 570         }
 571
 572         irq = platform_get_irq(pdev, 0);
 573         if (irq < 0 || irq >= nr_irqs)
 574                 return -EBUSY;
 575
 576         return cascade_irq(irq, giu_get_irq);
 577 }
 578
 579 static int giu_remove(struct platform_device *pdev)
 580 {
 581         if (giu_base) {
 582                 iounmap(giu_base);
 583                 giu_base = NULL;
 584         }
 585
 586         return 0;
 587 }
 588
 589 static struct platform_driver giu_device_driver = {
 590         .probe          = giu_probe,
 591         .remove         = giu_remove,
 592         .driver         = {
 593                 .name   = "GIU",
 594         },
 595 };
 596
 597 module_platform_driver(giu_device_driver);