drivers/gpio/gpio-pl061.c

   1 /*
   2  * Copyright (C) 2008, 2009 Provigent Ltd.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * Driver for the ARM PrimeCell(tm) General Purpose Input/Output (PL061)
   9  *
  10  * Data sheet: ARM DDI 0190B, September 2000
  11  */
  12 #include <linux/spinlock.h>
  13 #include <linux/errno.h>
  14 #include <linux/module.h>
  15 #include <linux/io.h>
  16 #include <linux/ioport.h>
  17 #include <linux/irq.h>
  18 #include <linux/irqdomain.h>
  19 #include <linux/irqchip/chained_irq.h>
  20 #include <linux/bitops.h>
  21 #include <linux/workqueue.h>
  22 #include <linux/gpio.h>
  23 #include <linux/device.h>
  24 #include <linux/amba/bus.h>
  25 #include <linux/amba/pl061.h>
  26 #include <linux/slab.h>
  27 #include <linux/pinctrl/consumer.h>
  28 #include <linux/pm.h>
  29
  30 #define GPIODIR 0x400
  31 #define GPIOIS  0x404
  32 #define GPIOIBE 0x408
  33 #define GPIOIEV 0x40C
  34 #define GPIOIE  0x410
  35 #define GPIORIS 0x414
  36 #define GPIOMIS 0x418
  37 #define GPIOIC  0x41C
  38
  39 #define PL061_GPIO_NR   8
  40
  41 #ifdef CONFIG_PM
  42 struct pl061_context_save_regs {
  43         u8 gpio_data;
  44         u8 gpio_dir;
  45         u8 gpio_is;
  46         u8 gpio_ibe;
  47         u8 gpio_iev;
  48         u8 gpio_ie;
  49 };
  50 #endif
  51
  52 struct pl061_gpio {
  53         spinlock_t              lock;
  54
  55         void __iomem            *base;
  56         struct irq_domain       *domain;
  57         struct gpio_chip        gc;
  58
  59 #ifdef CONFIG_PM
  60         struct pl061_context_save_regs csave_regs;
  61 #endif
  62 };
  63
  64 static int pl061_gpio_request(struct gpio_chip *chip, unsigned offset)
  65 {
  66         /*
  67          * Map back to global GPIO space and request muxing, the direction
  68          * parameter does not matter for this controller.
  69          */
  70         int gpio = chip->base + offset;
  71
  72         return pinctrl_request_gpio(gpio);
  73 }
  74
  75 static void pl061_gpio_free(struct gpio_chip *chip, unsigned offset)
  76 {
  77         int gpio = chip->base + offset;
  78
  79         pinctrl_free_gpio(gpio);
  80 }
  81
  82 static int pl061_direction_input(struct gpio_chip *gc, unsigned offset)
  83 {
  84         struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
  85         unsigned long flags;
  86         unsigned char gpiodir;
  87
  88         if (offset >= gc->ngpio)
  89                 return -EINVAL;
  90
  91         spin_lock_irqsave(&chip->lock, flags);
  92         gpiodir = readb(chip->base + GPIODIR);
  93         gpiodir &= ~(1 << offset);
  94         writeb(gpiodir, chip->base + GPIODIR);
  95         spin_unlock_irqrestore(&chip->lock, flags);
  96
  97         return 0;
  98 }
  99
 100 static int pl061_direction_output(struct gpio_chip *gc, unsigned offset,
 101                 int value)
 102 {
 103         struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
 104         unsigned long flags;
 105         unsigned char gpiodir;
 106
 107         if (offset >= gc->ngpio)
 108                 return -EINVAL;
 109
 110         spin_lock_irqsave(&chip->lock, flags);
 111         writeb(!!value << offset, chip->base + (1 << (offset + 2)));
 112         gpiodir = readb(chip->base + GPIODIR);
 113         gpiodir |= 1 << offset;
 114         writeb(gpiodir, chip->base + GPIODIR);
 115
 116         /*
 117          * gpio value is set again, because pl061 doesn't allow to set value of
 118          * a gpio pin before configuring it in OUT mode.
 119          */
 120         writeb(!!value << offset, chip->base + (1 << (offset + 2)));
 121         spin_unlock_irqrestore(&chip->lock, flags);
 122
 123         return 0;
 124 }
 125
 126 static int pl061_get_value(struct gpio_chip *gc, unsigned offset)
 127 {
 128         struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
 129
 130         return !!readb(chip->base + (1 << (offset + 2)));
 131 }
 132
 133 static void pl061_set_value(struct gpio_chip *gc, unsigned offset, int value)
 134 {
 135         struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
 136
 137         writeb(!!value << offset, chip->base + (1 << (offset + 2)));
 138 }
 139
 140 static int pl061_to_irq(struct gpio_chip *gc, unsigned offset)
 141 {
 142         struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc);
 143
 144         return irq_create_mapping(chip->domain, offset);
 145 }
 146
 147 static int pl061_irq_type(struct irq_data *d, unsigned trigger)
 148 {
 149         struct pl061_gpio *chip = irq_data_get_irq_chip_data(d);
 150         int offset = irqd_to_hwirq(d);
 151         unsigned long flags;
 152         u8 gpiois, gpioibe, gpioiev;
 153
 154         if (offset < 0 || offset >= PL061_GPIO_NR)
 155                 return -EINVAL;
 156
 157         spin_lock_irqsave(&chip->lock, flags);
 158
 159         gpioiev = readb(chip->base + GPIOIEV);
 160
 161         gpiois = readb(chip->base + GPIOIS);
 162         if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
 163                 gpiois |= 1 << offset;
 164                 if (trigger & IRQ_TYPE_LEVEL_HIGH)
 165                         gpioiev |= 1 << offset;
 166                 else
 167                         gpioiev &= ~(1 << offset);
 168         } else
 169                 gpiois &= ~(1 << offset);
 170         writeb(gpiois, chip->base + GPIOIS);
 171
 172         gpioibe = readb(chip->base + GPIOIBE);
 173         if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
 174                 gpioibe |= 1 << offset;
 175         else {
 176                 gpioibe &= ~(1 << offset);
 177                 if (trigger & IRQ_TYPE_EDGE_RISING)
 178                         gpioiev |= 1 << offset;
 179                 else if (trigger & IRQ_TYPE_EDGE_FALLING)
 180                         gpioiev &= ~(1 << offset);
 181         }
 182         writeb(gpioibe, chip->base + GPIOIBE);
 183
 184         writeb(gpioiev, chip->base + GPIOIEV);
 185
 186         spin_unlock_irqrestore(&chip->lock, flags);
 187
 188         return 0;
 189 }
 190
 191 static void pl061_irq_handler(unsigned irq, struct irq_desc *desc)
 192 {
 193         unsigned long pending;
 194         int offset;
 195         struct pl061_gpio *chip = irq_desc_get_handler_data(desc);
 196         struct irq_chip *irqchip = irq_desc_get_chip(desc);
 197
 198         chained_irq_enter(irqchip, desc);
 199
 200         pending = readb(chip->base + GPIOMIS);
 201         writeb(pending, chip->base + GPIOIC);
 202         if (pending) {
 203                 for_each_set_bit(offset, &pending, PL061_GPIO_NR)
 204                         generic_handle_irq(pl061_to_irq(&chip->gc, offset));
 205         }
 206
 207         chained_irq_exit(irqchip, desc);
 208 }
 209
 210 static void pl061_irq_mask(struct irq_data *d)
 211 {
 212         struct pl061_gpio *chip = irq_data_get_irq_chip_data(d);
 213         u8 mask = 1 << (irqd_to_hwirq(d) % PL061_GPIO_NR);
 214         u8 gpioie;
 215
 216         spin_lock(&chip->lock);
 217         gpioie = readb(chip->base + GPIOIE) & ~mask;
 218         writeb(gpioie, chip->base + GPIOIE);
 219         spin_unlock(&chip->lock);
 220 }
 221
 222 static void pl061_irq_unmask(struct irq_data *d)
 223 {
 224         struct pl061_gpio *chip = irq_data_get_irq_chip_data(d);
 225         u8 mask = 1 << (irqd_to_hwirq(d) % PL061_GPIO_NR);
 226         u8 gpioie;
 227
 228         spin_lock(&chip->lock);
 229         gpioie = readb(chip->base + GPIOIE) | mask;
 230         writeb(gpioie, chip->base + GPIOIE);
 231         spin_unlock(&chip->lock);
 232 }
 233
 234 static struct irq_chip pl061_irqchip = {
 235         .name           = "pl061 gpio",
 236         .irq_mask       = pl061_irq_mask,
 237         .irq_unmask     = pl061_irq_unmask,
 238         .irq_set_type   = pl061_irq_type,
 239 };
 240
 241 static int pl061_irq_map(struct irq_domain *d, unsigned int virq,
 242                          irq_hw_number_t hw)
 243 {
 244         struct pl061_gpio *chip = d->host_data;
 245
 246         irq_set_chip_and_handler_name(virq, &pl061_irqchip, handle_simple_irq,
 247                                       "pl061");
 248         irq_set_chip_data(virq, chip);
 249         irq_set_irq_type(virq, IRQ_TYPE_NONE);
 250
 251         return 0;
 252 }
 253
 254 static const struct irq_domain_ops pl061_domain_ops = {
 255         .map    = pl061_irq_map,
 256         .xlate  = irq_domain_xlate_twocell,
 257 };
 258
 259 static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
 260 {
 261         struct device *dev = &adev->dev;
 262         struct pl061_platform_data *pdata = dev->platform_data;
 263         struct pl061_gpio *chip;
 264         int ret, irq, i, irq_base;
 265
 266         chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 267         if (chip == NULL)
 268                 return -ENOMEM;
 269
 270         if (pdata) {
 271                 chip->gc.base = pdata->gpio_base;
 272                 irq_base = pdata->irq_base;
 273                 if (irq_base <= 0)
 274                         return -ENODEV;
 275         } else {
 276                 chip->gc.base = -1;
 277                 irq_base = 0;
 278         }
 279
 280         if (!devm_request_mem_region(dev, adev->res.start,
 281                                      resource_size(&adev->res), "pl061"))
 282                 return -EBUSY;
 283
 284         chip->base = devm_ioremap(dev, adev->res.start,
 285                                   resource_size(&adev->res));
 286         if (!chip->base)
 287                 return -ENOMEM;
 288
 289         spin_lock_init(&chip->lock);
 290
 291         chip->gc.request = pl061_gpio_request;
 292         chip->gc.free = pl061_gpio_free;
 293         chip->gc.direction_input = pl061_direction_input;
 294         chip->gc.direction_output = pl061_direction_output;
 295         chip->gc.get = pl061_get_value;
 296         chip->gc.set = pl061_set_value;
 297         chip->gc.to_irq = pl061_to_irq;
 298         chip->gc.ngpio = PL061_GPIO_NR;
 299         chip->gc.label = dev_name(dev);
 300         chip->gc.dev = dev;
 301         chip->gc.owner = THIS_MODULE;
 302
 303         ret = gpiochip_add(&chip->gc);
 304         if (ret)
 305                 return ret;
 306
 307         /*
 308          * irq_chip support
 309          */
 310         writeb(0, chip->base + GPIOIE); /* disable irqs */
 311         irq = adev->irq[0];
 312         if (irq < 0)
 313                 return -ENODEV;
 314
 315         irq_set_chained_handler(irq, pl061_irq_handler);
 316         irq_set_handler_data(irq, chip);
 317
 318         chip->domain = irq_domain_add_simple(adev->dev.of_node, PL061_GPIO_NR,
 319                                              irq_base, &pl061_domain_ops, chip);
 320         if (!chip->domain)
 321                 return -ENODEV;
 322
 323         for (i = 0; i < PL061_GPIO_NR; i++) {
 324                 if (pdata) {
 325                         if (pdata->directions & (1 << i))
 326                                 pl061_direction_output(&chip->gc, i,
 327                                                 pdata->values & (1 << i));
 328                         else
 329                                 pl061_direction_input(&chip->gc, i);
 330                 }
 331         }
 332
 333         amba_set_drvdata(adev, chip);
 334
 335         return 0;
 336 }
 337
 338 #ifdef CONFIG_PM
 339 static int pl061_suspend(struct device *dev)
 340 {
 341         struct pl061_gpio *chip = dev_get_drvdata(dev);
 342         int offset;
 343
 344         chip->csave_regs.gpio_data = 0;
 345         chip->csave_regs.gpio_dir = readb(chip->base + GPIODIR);
 346         chip->csave_regs.gpio_is = readb(chip->base + GPIOIS);
 347         chip->csave_regs.gpio_ibe = readb(chip->base + GPIOIBE);
 348         chip->csave_regs.gpio_iev = readb(chip->base + GPIOIEV);
 349         chip->csave_regs.gpio_ie = readb(chip->base + GPIOIE);
 350
 351         for (offset = 0; offset < PL061_GPIO_NR; offset++) {
 352                 if (chip->csave_regs.gpio_dir & (1 << offset))
 353                         chip->csave_regs.gpio_data |=
 354                                 pl061_get_value(&chip->gc, offset) << offset;
 355         }
 356
 357         return 0;
 358 }
 359
 360 static int pl061_resume(struct device *dev)
 361 {
 362         struct pl061_gpio *chip = dev_get_drvdata(dev);
 363         int offset;
 364
 365         for (offset = 0; offset < PL061_GPIO_NR; offset++) {
 366                 if (chip->csave_regs.gpio_dir & (1 << offset))
 367                         pl061_direction_output(&chip->gc, offset,
 368                                         chip->csave_regs.gpio_data &
 369                                         (1 << offset));
 370                 else
 371                         pl061_direction_input(&chip->gc, offset);
 372         }
 373
 374         writeb(chip->csave_regs.gpio_is, chip->base + GPIOIS);
 375         writeb(chip->csave_regs.gpio_ibe, chip->base + GPIOIBE);
 376         writeb(chip->csave_regs.gpio_iev, chip->base + GPIOIEV);
 377         writeb(chip->csave_regs.gpio_ie, chip->base + GPIOIE);
 378
 379         return 0;
 380 }
 381
 382 static const struct dev_pm_ops pl061_dev_pm_ops = {
 383         .suspend = pl061_suspend,
 384         .resume = pl061_resume,
 385         .freeze = pl061_suspend,
 386         .restore = pl061_resume,
 387 };
 388 #endif
 389
 390 static struct amba_id pl061_ids[] = {
 391         {
 392                 .id     = 0x00041061,
 393                 .mask   = 0x000fffff,
 394         },
 395         { 0, 0 },
 396 };
 397
 398 MODULE_DEVICE_TABLE(amba, pl061_ids);
 399
 400 static struct amba_driver pl061_gpio_driver = {
 401         .drv = {
 402                 .name   = "pl061_gpio",
 403 #ifdef CONFIG_PM
 404                 .pm     = &pl061_dev_pm_ops,
 405 #endif
 406         },
 407         .id_table       = pl061_ids,
 408         .probe          = pl061_probe,
 409 };
 410
 411 static int __init pl061_gpio_init(void)
 412 {
 413         return amba_driver_register(&pl061_gpio_driver);
 414 }
 415 module_init(pl061_gpio_init);
 416
 417 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 418 MODULE_DESCRIPTION("PL061 GPIO driver");
 419 MODULE_LICENSE("GPL");