LXR linux/drivers/gpio/gpio-rcar.c

   1/*
   2 * Renesas R-Car GPIO Support
   3 *
   4 *  Copyright (C) 2014 Renesas Electronics Corporation
   5 *  Copyright (C) 2013 Magnus Damm
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation; either version 2 of the License
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 */
  16
  17#include <linux/err.h>
  18#include <linux/gpio/driver.h>
  19#include <linux/init.h>
  20#include <linux/interrupt.h>
  21#include <linux/io.h>
  22#include <linux/ioport.h>
  23#include <linux/irq.h>
  24#include <linux/module.h>
  25#include <linux/of.h>
  26#include <linux/of_device.h>
  27#include <linux/pinctrl/consumer.h>
  28#include <linux/platform_device.h>
  29#include <linux/pm_runtime.h>
  30#include <linux/spinlock.h>
  31#include <linux/slab.h>
  32
  33struct gpio_rcar_bank_info {
  34        u32 iointsel;
  35        u32 inoutsel;
  36        u32 outdt;
  37        u32 posneg;
  38        u32 edglevel;
  39        u32 bothedge;
  40        u32 intmsk;
  41};
  42
  43struct gpio_rcar_priv {
  44        void __iomem *base;
  45        spinlock_t lock;
  46        struct platform_device *pdev;
  47        struct gpio_chip gpio_chip;
  48        struct irq_chip irq_chip;
  49        unsigned int irq_parent;
  50        atomic_t wakeup_path;
  51        bool has_both_edge_trigger;
  52        struct gpio_rcar_bank_info bank_info;
  53};
  54
  55#define IOINTSEL 0x00   /* General IO/Interrupt Switching Register */
  56#define INOUTSEL 0x04   /* General Input/Output Switching Register */
  57#define OUTDT 0x08      /* General Output Register */
  58#define INDT 0x0c       /* General Input Register */
  59#define INTDT 0x10      /* Interrupt Display Register */
  60#define INTCLR 0x14     /* Interrupt Clear Register */
  61#define INTMSK 0x18     /* Interrupt Mask Register */
  62#define MSKCLR 0x1c     /* Interrupt Mask Clear Register */
  63#define POSNEG 0x20     /* Positive/Negative Logic Select Register */
  64#define EDGLEVEL 0x24   /* Edge/level Select Register */
  65#define FILONOFF 0x28   /* Chattering Prevention On/Off Register */
  66#define BOTHEDGE 0x4c   /* One Edge/Both Edge Select Register */
  67
  68#define RCAR_MAX_GPIO_PER_BANK          32
  69
  70static inline u32 gpio_rcar_read(struct gpio_rcar_priv *p, int offs)
  71{
  72        return ioread32(p->base + offs);
  73}
  74
  75static inline void gpio_rcar_write(struct gpio_rcar_priv *p, int offs,
  76                                   u32 value)
  77{
  78        iowrite32(value, p->base + offs);
  79}
  80
  81static void gpio_rcar_modify_bit(struct gpio_rcar_priv *p, int offs,
  82                                 int bit, bool value)
  83{
  84        u32 tmp = gpio_rcar_read(p, offs);
  85
  86        if (value)
  87                tmp |= BIT(bit);
  88        else
  89                tmp &= ~BIT(bit);
  90
  91        gpio_rcar_write(p, offs, tmp);
  92}
  93
  94static void gpio_rcar_irq_disable(struct irq_data *d)
  95{
  96        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
  97        struct gpio_rcar_priv *p = gpiochip_get_data(gc);
  98
  99        gpio_rcar_write(p, INTMSK, ~BIT(irqd_to_hwirq(d)));
 100}
 101
 102static void gpio_rcar_irq_enable(struct irq_data *d)
 103{
 104        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 105        struct gpio_rcar_priv *p = gpiochip_get_data(gc);
 106
 107        gpio_rcar_write(p, MSKCLR, BIT(irqd_to_hwirq(d)));
 108}
 109
 110static void gpio_rcar_config_interrupt_input_mode(struct gpio_rcar_priv *p,
 111                                                  unsigned int hwirq,
 112                                                  bool active_high_rising_edge,
 113                                                  bool level_trigger,
 114                                                  bool both)
 115{
 116        unsigned long flags;
 117
 118        /* follow steps in the GPIO documentation for
 119         * "Setting Edge-Sensitive Interrupt Input Mode" and
 120         * "Setting Level-Sensitive Interrupt Input Mode"
 121         */
 122
 123        spin_lock_irqsave(&p->lock, flags);
 124
 125        /* Configure postive or negative logic in POSNEG */
 126        gpio_rcar_modify_bit(p, POSNEG, hwirq, !active_high_rising_edge);
 127
 128        /* Configure edge or level trigger in EDGLEVEL */
 129        gpio_rcar_modify_bit(p, EDGLEVEL, hwirq, !level_trigger);
 130
 131        /* Select one edge or both edges in BOTHEDGE */
 132        if (p->has_both_edge_trigger)
 133                gpio_rcar_modify_bit(p, BOTHEDGE, hwirq, both);
 134
 135        /* Select "Interrupt Input Mode" in IOINTSEL */
 136        gpio_rcar_modify_bit(p, IOINTSEL, hwirq, true);
 137
 138        /* Write INTCLR in case of edge trigger */
 139        if (!level_trigger)
 140                gpio_rcar_write(p, INTCLR, BIT(hwirq));
 141
 142        spin_unlock_irqrestore(&p->lock, flags);
 143}
 144
 145static int gpio_rcar_irq_set_type(struct irq_data *d, unsigned int type)
 146{
 147        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 148        struct gpio_rcar_priv *p = gpiochip_get_data(gc);
 149        unsigned int hwirq = irqd_to_hwirq(d);
 150
 151        dev_dbg(&p->pdev->dev, "sense irq = %d, type = %d\n", hwirq, type);
 152
 153        switch (type & IRQ_TYPE_SENSE_MASK) {
 154        case IRQ_TYPE_LEVEL_HIGH:
 155                gpio_rcar_config_interrupt_input_mode(p, hwirq, true, true,
 156                                                      false);
 157                break;
 158        case IRQ_TYPE_LEVEL_LOW:
 159                gpio_rcar_config_interrupt_input_mode(p, hwirq, false, true,
 160                                                      false);
 161                break;
 162        case IRQ_TYPE_EDGE_RISING:
 163                gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
 164                                                      false);
 165                break;
 166        case IRQ_TYPE_EDGE_FALLING:
 167                gpio_rcar_config_interrupt_input_mode(p, hwirq, false, false,
 168                                                      false);
 169                break;
 170        case IRQ_TYPE_EDGE_BOTH:
 171                if (!p->has_both_edge_trigger)
 172                        return -EINVAL;
 173                gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
 174                                                      true);
 175                break;
 176        default:
 177                return -EINVAL;
 178        }
 179        return 0;
 180}
 181
 182static int gpio_rcar_irq_set_wake(struct irq_data *d, unsigned int on)
 183{
 184        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 185        struct gpio_rcar_priv *p = gpiochip_get_data(gc);
 186        int error;
 187
 188        if (p->irq_parent) {
 189                error = irq_set_irq_wake(p->irq_parent, on);
 190                if (error) {
 191                        dev_dbg(&p->pdev->dev,
 192                                "irq %u doesn't support irq_set_wake\n",
 193                                p->irq_parent);
 194                        p->irq_parent = 0;
 195                }
 196        }
 197
 198        if (on)
 199                atomic_inc(&p->wakeup_path);
 200        else
 201                atomic_dec(&p->wakeup_path);
 202
 203        return 0;
 204}
 205
 206static irqreturn_t gpio_rcar_irq_handler(int irq, void *dev_id)
 207{
 208        struct gpio_rcar_priv *p = dev_id;
 209        u32 pending;
 210        unsigned int offset, irqs_handled = 0;
 211
 212        while ((pending = gpio_rcar_read(p, INTDT) &
 213                          gpio_rcar_read(p, INTMSK))) {
 214                offset = __ffs(pending);
 215                gpio_rcar_write(p, INTCLR, BIT(offset));
 216                generic_handle_irq(irq_find_mapping(p->gpio_chip.irq.domain,
 217                                                    offset));
 218                irqs_handled++;
 219        }
 220
 221        return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
 222}
 223
 224static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip,
 225                                                       unsigned int gpio,
 226                                                       bool output)
 227{
 228        struct gpio_rcar_priv *p = gpiochip_get_data(chip);
 229        unsigned long flags;
 230
 231        /* follow steps in the GPIO documentation for
 232         * "Setting General Output Mode" and
 233         * "Setting General Input Mode"
 234         */
 235
 236        spin_lock_irqsave(&p->lock, flags);
 237
 238        /* Configure postive logic in POSNEG */
 239        gpio_rcar_modify_bit(p, POSNEG, gpio, false);
 240
 241        /* Select "General Input/Output Mode" in IOINTSEL */
 242        gpio_rcar_modify_bit(p, IOINTSEL, gpio, false);
 243
 244        /* Select Input Mode or Output Mode in INOUTSEL */
 245        gpio_rcar_modify_bit(p, INOUTSEL, gpio, output);
 246
 247        spin_unlock_irqrestore(&p->lock, flags);
 248}
 249
 250static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset)
 251{
 252        struct gpio_rcar_priv *p = gpiochip_get_data(chip);
 253        int error;
 254
 255        error = pm_runtime_get_sync(&p->pdev->dev);
 256        if (error < 0)
 257                return error;
 258
 259        error = pinctrl_gpio_request(chip->base + offset);
 260        if (error)
 261                pm_runtime_put(&p->pdev->dev);
 262
 263        return error;
 264}
 265
 266static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset)
 267{
 268        struct gpio_rcar_priv *p = gpiochip_get_data(chip);
 269
 270        pinctrl_gpio_free(chip->base + offset);
 271
 272        /*
 273         * Set the GPIO as an input to ensure that the next GPIO request won't
 274         * drive the GPIO pin as an output.
 275         */
 276        gpio_rcar_config_general_input_output_mode(chip, offset, false);
 277
 278        pm_runtime_put(&p->pdev->dev);
 279}
 280
 281static int gpio_rcar_get_direction(struct gpio_chip *chip, unsigned int offset)
 282{
 283        struct gpio_rcar_priv *p = gpiochip_get_data(chip);
 284
 285        return !(gpio_rcar_read(p, INOUTSEL) & BIT(offset));
 286}
 287
 288static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset)
 289{
 290        gpio_rcar_config_general_input_output_mode(chip, offset, false);
 291        return 0;
 292}
 293
 294static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset)
 295{
 296        u32 bit = BIT(offset);
 297
 298        /* testing on r8a7790 shows that INDT does not show correct pin state
 299         * when configured as output, so use OUTDT in case of output pins */
 300        if (gpio_rcar_read(gpiochip_get_data(chip), INOUTSEL) & bit)
 301                return !!(gpio_rcar_read(gpiochip_get_data(chip), OUTDT) & bit);
 302        else
 303                return !!(gpio_rcar_read(gpiochip_get_data(chip), INDT) & bit);
 304}
 305
 306static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value)
 307{
 308        struct gpio_rcar_priv *p = gpiochip_get_data(chip);
 309        unsigned long flags;
 310
 311        spin_lock_irqsave(&p->lock, flags);
 312        gpio_rcar_modify_bit(p, OUTDT, offset, value);
 313        spin_unlock_irqrestore(&p->lock, flags);
 314}
 315
 316static void gpio_rcar_set_multiple(struct gpio_chip *chip, unsigned long *mask,
 317                                   unsigned long *bits)
 318{
 319        struct gpio_rcar_priv *p = gpiochip_get_data(chip);
 320        unsigned long flags;
 321        u32 val, bankmask;
 322
 323        bankmask = mask[0] & GENMASK(chip->ngpio - 1, 0);
 324        if (!bankmask)
 325                return;
 326
 327        spin_lock_irqsave(&p->lock, flags);
 328        val = gpio_rcar_read(p, OUTDT);
 329        val &= ~bankmask;
 330        val |= (bankmask & bits[0]);
 331        gpio_rcar_write(p, OUTDT, val);
 332        spin_unlock_irqrestore(&p->lock, flags);
 333}
 334
 335static int gpio_rcar_direction_output(struct gpio_chip *chip, unsigned offset,
 336                                      int value)
 337{
 338        /* write GPIO value to output before selecting output mode of pin */
 339        gpio_rcar_set(chip, offset, value);
 340        gpio_rcar_config_general_input_output_mode(chip, offset, true);
 341        return 0;
 342}
 343
 344struct gpio_rcar_info {
 345        bool has_both_edge_trigger;
 346};
 347
 348static const struct gpio_rcar_info gpio_rcar_info_gen1 = {
 349        .has_both_edge_trigger = false,
 350};
 351
 352static const struct gpio_rcar_info gpio_rcar_info_gen2 = {
 353        .has_both_edge_trigger = true,
 354};
 355
 356static const struct of_device_id gpio_rcar_of_table[] = {
 357        {
 358                .compatible = "renesas,gpio-r8a7743",
 359                /* RZ/G1 GPIO is identical to R-Car Gen2. */
 360                .data = &gpio_rcar_info_gen2,
 361        }, {
 362                .compatible = "renesas,gpio-r8a7790",
 363                .data = &gpio_rcar_info_gen2,
 364        }, {
 365                .compatible = "renesas,gpio-r8a7791",
 366                .data = &gpio_rcar_info_gen2,
 367        }, {
 368                .compatible = "renesas,gpio-r8a7792",
 369                .data = &gpio_rcar_info_gen2,
 370        }, {
 371                .compatible = "renesas,gpio-r8a7793",
 372                .data = &gpio_rcar_info_gen2,
 373        }, {
 374                .compatible = "renesas,gpio-r8a7794",
 375                .data = &gpio_rcar_info_gen2,
 376        }, {
 377                .compatible = "renesas,gpio-r8a7795",
 378                /* Gen3 GPIO is identical to Gen2. */
 379                .data = &gpio_rcar_info_gen2,
 380        }, {
 381                .compatible = "renesas,gpio-r8a7796",
 382                /* Gen3 GPIO is identical to Gen2. */
 383                .data = &gpio_rcar_info_gen2,
 384        }, {
 385                .compatible = "renesas,rcar-gen1-gpio",
 386                .data = &gpio_rcar_info_gen1,
 387        }, {
 388                .compatible = "renesas,rcar-gen2-gpio",
 389                .data = &gpio_rcar_info_gen2,
 390        }, {
 391                .compatible = "renesas,rcar-gen3-gpio",
 392                /* Gen3 GPIO is identical to Gen2. */
 393                .data = &gpio_rcar_info_gen2,
 394        }, {
 395                .compatible = "renesas,gpio-rcar",
 396                .data = &gpio_rcar_info_gen1,
 397        }, {
 398                /* Terminator */
 399        },
 400};
 401
 402MODULE_DEVICE_TABLE(of, gpio_rcar_of_table);
 403
 404static int gpio_rcar_parse_dt(struct gpio_rcar_priv *p, unsigned int *npins)
 405{
 406        struct device_node *np = p->pdev->dev.of_node;
 407        const struct gpio_rcar_info *info;
 408        struct of_phandle_args args;
 409        int ret;
 410
 411        info = of_device_get_match_data(&p->pdev->dev);
 412
 413        ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &args);
 414        *npins = ret == 0 ? args.args[2] : RCAR_MAX_GPIO_PER_BANK;
 415        p->has_both_edge_trigger = info->has_both_edge_trigger;
 416
 417        if (*npins == 0 || *npins > RCAR_MAX_GPIO_PER_BANK) {
 418                dev_warn(&p->pdev->dev,
 419                         "Invalid number of gpio lines %u, using %u\n", *npins,
 420                         RCAR_MAX_GPIO_PER_BANK);
 421                *npins = RCAR_MAX_GPIO_PER_BANK;
 422        }
 423
 424        return 0;
 425}
 426
 427static int gpio_rcar_probe(struct platform_device *pdev)
 428{
 429        struct gpio_rcar_priv *p;
 430        struct resource *io, *irq;
 431        struct gpio_chip *gpio_chip;
 432        struct irq_chip *irq_chip;
 433        struct device *dev = &pdev->dev;
 434        const char *name = dev_name(dev);
 435        unsigned int npins;
 436        int ret;
 437
 438        p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
 439        if (!p)
 440                return -ENOMEM;
 441
 442        p->pdev = pdev;
 443        spin_lock_init(&p->lock);
 444
 445        /* Get device configuration from DT node */
 446        ret = gpio_rcar_parse_dt(p, &npins);
 447        if (ret < 0)
 448                return ret;
 449
 450        platform_set_drvdata(pdev, p);
 451
 452        pm_runtime_enable(dev);
 453
 454        irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 455        if (!irq) {
 456                dev_err(dev, "missing IRQ\n");
 457                ret = -EINVAL;
 458                goto err0;
 459        }
 460
 461        io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 462        p->base = devm_ioremap_resource(dev, io);
 463        if (IS_ERR(p->base)) {
 464                ret = PTR_ERR(p->base);
 465                goto err0;
 466        }
 467
 468        gpio_chip = &p->gpio_chip;
 469        gpio_chip->request = gpio_rcar_request;
 470        gpio_chip->free = gpio_rcar_free;
 471        gpio_chip->get_direction = gpio_rcar_get_direction;
 472        gpio_chip->direction_input = gpio_rcar_direction_input;
 473        gpio_chip->get = gpio_rcar_get;
 474        gpio_chip->direction_output = gpio_rcar_direction_output;
 475        gpio_chip->set = gpio_rcar_set;
 476        gpio_chip->set_multiple = gpio_rcar_set_multiple;
 477        gpio_chip->label = name;
 478        gpio_chip->parent = dev;
 479        gpio_chip->owner = THIS_MODULE;
 480        gpio_chip->base = -1;
 481        gpio_chip->ngpio = npins;
 482
 483        irq_chip = &p->irq_chip;
 484        irq_chip->name = name;
 485        irq_chip->parent_device = dev;
 486        irq_chip->irq_mask = gpio_rcar_irq_disable;
 487        irq_chip->irq_unmask = gpio_rcar_irq_enable;
 488        irq_chip->irq_set_type = gpio_rcar_irq_set_type;
 489        irq_chip->irq_set_wake = gpio_rcar_irq_set_wake;
 490        irq_chip->flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_MASK_ON_SUSPEND;
 491
 492        ret = gpiochip_add_data(gpio_chip, p);
 493        if (ret) {
 494                dev_err(dev, "failed to add GPIO controller\n");
 495                goto err0;
 496        }
 497
 498        ret = gpiochip_irqchip_add(gpio_chip, irq_chip, 0, handle_level_irq,
 499                                   IRQ_TYPE_NONE);
 500        if (ret) {
 501                dev_err(dev, "cannot add irqchip\n");
 502                goto err1;
 503        }
 504
 505        p->irq_parent = irq->start;
 506        if (devm_request_irq(dev, irq->start, gpio_rcar_irq_handler,
 507                             IRQF_SHARED, name, p)) {
 508                dev_err(dev, "failed to request IRQ\n");
 509                ret = -ENOENT;
 510                goto err1;
 511        }
 512
 513        dev_info(dev, "driving %d GPIOs\n", npins);
 514
 515        return 0;
 516
 517err1:
 518        gpiochip_remove(gpio_chip);
 519err0:
 520        pm_runtime_disable(dev);
 521        return ret;
 522}
 523
 524static int gpio_rcar_remove(struct platform_device *pdev)
 525{
 526        struct gpio_rcar_priv *p = platform_get_drvdata(pdev);
 527
 528        gpiochip_remove(&p->gpio_chip);
 529
 530        pm_runtime_disable(&pdev->dev);
 531        return 0;
 532}
 533
 534#ifdef CONFIG_PM_SLEEP
 535static int gpio_rcar_suspend(struct device *dev)
 536{
 537        struct gpio_rcar_priv *p = dev_get_drvdata(dev);
 538
 539        p->bank_info.iointsel = gpio_rcar_read(p, IOINTSEL);
 540        p->bank_info.inoutsel = gpio_rcar_read(p, INOUTSEL);
 541        p->bank_info.outdt = gpio_rcar_read(p, OUTDT);
 542        p->bank_info.intmsk = gpio_rcar_read(p, INTMSK);
 543        p->bank_info.posneg = gpio_rcar_read(p, POSNEG);
 544        p->bank_info.edglevel = gpio_rcar_read(p, EDGLEVEL);
 545        if (p->has_both_edge_trigger)
 546                p->bank_info.bothedge = gpio_rcar_read(p, BOTHEDGE);
 547
 548        if (atomic_read(&p->wakeup_path))
 549                device_set_wakeup_path(dev);
 550
 551        return 0;
 552}
 553
 554static int gpio_rcar_resume(struct device *dev)
 555{
 556        struct gpio_rcar_priv *p = dev_get_drvdata(dev);
 557        unsigned int offset;
 558        u32 mask;
 559
 560        for (offset = 0; offset < p->gpio_chip.ngpio; offset++) {
 561                mask = BIT(offset);
 562                /* I/O pin */
 563                if (!(p->bank_info.iointsel & mask)) {
 564                        if (p->bank_info.inoutsel & mask)
 565                                gpio_rcar_direction_output(
 566                                        &p->gpio_chip, offset,
 567                                        !!(p->bank_info.outdt & mask));
 568                        else
 569                                gpio_rcar_direction_input(&p->gpio_chip,
 570                                                          offset);
 571                } else {
 572                        /* Interrupt pin */
 573                        gpio_rcar_config_interrupt_input_mode(
 574                                p,
 575                                offset,
 576                                !(p->bank_info.posneg & mask),
 577                                !(p->bank_info.edglevel & mask),
 578                                !!(p->bank_info.bothedge & mask));
 579
 580                        if (p->bank_info.intmsk & mask)
 581                                gpio_rcar_write(p, MSKCLR, mask);
 582                }
 583        }
 584
 585        return 0;
 586}
 587#endif /* CONFIG_PM_SLEEP*/
 588
 589static SIMPLE_DEV_PM_OPS(gpio_rcar_pm_ops, gpio_rcar_suspend, gpio_rcar_resume);
 590
 591static struct platform_driver gpio_rcar_device_driver = {
 592        .probe          = gpio_rcar_probe,
 593        .remove         = gpio_rcar_remove,
 594        .driver         = {
 595                .name   = "gpio_rcar",
 596                .pm     = &gpio_rcar_pm_ops,
 597                .of_match_table = of_match_ptr(gpio_rcar_of_table),
 598        }
 599};
 600
 601module_platform_driver(gpio_rcar_device_driver);
 602
 603MODULE_AUTHOR("Magnus Damm");
 604MODULE_DESCRIPTION("Renesas R-Car GPIO Driver");
 605MODULE_LICENSE("GPL v2");
 606