drivers/gpio/gpio-mpc8xxx.c

   1 /*
   2  * GPIOs on MPC512x/8349/8572/8610/QorIQ and compatible
   3  *
   4  * Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
   5  * Copyright (C) 2016 Freescale Semiconductor Inc.
   6  *
   7  * This file is licensed under the terms of the GNU General Public License
   8  * version 2.  This program is licensed "as is" without any warranty of any
   9  * kind, whether express or implied.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/io.h>
  16 #include <linux/of.h>
  17 #include <linux/of_gpio.h>
  18 #include <linux/of_address.h>
  19 #include <linux/of_irq.h>
  20 #include <linux/of_platform.h>
  21 #include <linux/slab.h>
  22 #include <linux/irq.h>
  23 #include <linux/gpio/driver.h>
  24 #include <linux/bitops.h>
  25 #include <linux/interrupt.h>
  26
  27 #define MPC8XXX_GPIO_PINS       32
  28
  29 #define GPIO_DIR                0x00
  30 #define GPIO_ODR                0x04
  31 #define GPIO_DAT                0x08
  32 #define GPIO_IER                0x0c
  33 #define GPIO_IMR                0x10
  34 #define GPIO_ICR                0x14
  35 #define GPIO_ICR2               0x18
  36 #define GPIO_IBE                0x18
  37
  38 struct mpc8xxx_gpio_chip {
  39         struct gpio_chip        gc;
  40         void __iomem *regs;
  41         raw_spinlock_t lock;
  42
  43         int (*direction_output)(struct gpio_chip *chip,
  44                                 unsigned offset, int value);
  45
  46         struct irq_domain *irq;
  47         unsigned int irqn;
  48 };
  49
  50 /* The GPIO Input Buffer Enable register(GPIO_IBE) is used to
  51  * control the input enable of each individual GPIO port.
  52  * When an individual GPIO port’s direction is set to
  53  * input (GPIO_GPDIR[DRn=0]), the associated input enable must be
  54  * set (GPIOxGPIE[IEn]=1) to propagate the port value to the GPIO
  55  * Data Register.
  56  */
  57 static int ls1028a_gpio_dir_in_init(struct gpio_chip *gc)
  58 {
  59         unsigned long flags;
  60         struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
  61
  62         spin_lock_irqsave(&gc->bgpio_lock, flags);
  63
  64         gc->write_reg(mpc8xxx_gc->regs + GPIO_IBE, 0xffffffff);
  65
  66         spin_unlock_irqrestore(&gc->bgpio_lock, flags);
  67
  68         return 0;
  69 }
  70
  71 /*
  72  * This hardware has a big endian bit assignment such that GPIO line 0 is
  73  * connected to bit 31, line 1 to bit 30 ... line 31 to bit 0.
  74  * This inline helper give the right bitmask for a certain line.
  75  */
  76 static inline u32 mpc_pin2mask(unsigned int offset)
  77 {
  78         return BIT(31 - offset);
  79 }
  80
  81 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
  82  * defined as output cannot be determined by reading GPDAT register,
  83  * so we use shadow data register instead. The status of input pins
  84  * is determined by reading GPDAT register.
  85  */
  86 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
  87 {
  88         u32 val;
  89         struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
  90         u32 out_mask, out_shadow;
  91
  92         out_mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
  93         val = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) & ~out_mask;
  94         out_shadow = gc->bgpio_data & out_mask;
  95
  96         return !!((val | out_shadow) & mpc_pin2mask(gpio));
  97 }
  98
  99 static int mpc5121_gpio_dir_out(struct gpio_chip *gc,
 100                                 unsigned int gpio, int val)
 101 {
 102         struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
 103         /* GPIO 28..31 are input only on MPC5121 */
 104         if (gpio >= 28)
 105                 return -EINVAL;
 106
 107         return mpc8xxx_gc->direction_output(gc, gpio, val);
 108 }
 109
 110 static int mpc5125_gpio_dir_out(struct gpio_chip *gc,
 111                                 unsigned int gpio, int val)
 112 {
 113         struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
 114         /* GPIO 0..3 are input only on MPC5125 */
 115         if (gpio <= 3)
 116                 return -EINVAL;
 117
 118         return mpc8xxx_gc->direction_output(gc, gpio, val);
 119 }
 120
 121 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 122 {
 123         struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
 124
 125         if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
 126                 return irq_create_mapping(mpc8xxx_gc->irq, offset);
 127         else
 128                 return -ENXIO;
 129 }
 130
 131 static irqreturn_t mpc8xxx_gpio_irq_cascade(int irq, void *data)
 132 {
 133         struct mpc8xxx_gpio_chip *mpc8xxx_gc = data;
 134         struct gpio_chip *gc = &mpc8xxx_gc->gc;
 135         unsigned long mask;
 136         int i;
 137
 138         mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_IER)
 139                 & gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR);
 140         for_each_set_bit(i, &mask, 32)
 141                 generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq, 31 - i));
 142
 143         return IRQ_HANDLED;
 144 }
 145
 146 static void mpc8xxx_irq_unmask(struct irq_data *d)
 147 {
 148         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 149         struct gpio_chip *gc = &mpc8xxx_gc->gc;
 150         unsigned long flags;
 151
 152         raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 153
 154         gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
 155                 gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
 156                 | mpc_pin2mask(irqd_to_hwirq(d)));
 157
 158         raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 159 }
 160
 161 static void mpc8xxx_irq_mask(struct irq_data *d)
 162 {
 163         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 164         struct gpio_chip *gc = &mpc8xxx_gc->gc;
 165         unsigned long flags;
 166
 167         raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 168
 169         gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
 170                 gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
 171                 & ~mpc_pin2mask(irqd_to_hwirq(d)));
 172
 173         raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 174 }
 175
 176 static void mpc8xxx_irq_ack(struct irq_data *d)
 177 {
 178         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 179         struct gpio_chip *gc = &mpc8xxx_gc->gc;
 180
 181         gc->write_reg(mpc8xxx_gc->regs + GPIO_IER,
 182                       mpc_pin2mask(irqd_to_hwirq(d)));
 183 }
 184
 185 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
 186 {
 187         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 188         struct gpio_chip *gc = &mpc8xxx_gc->gc;
 189         unsigned long flags;
 190
 191         switch (flow_type) {
 192         case IRQ_TYPE_EDGE_FALLING:
 193                 raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 194                 gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
 195                         gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
 196                         | mpc_pin2mask(irqd_to_hwirq(d)));
 197                 raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 198                 break;
 199
 200         case IRQ_TYPE_EDGE_BOTH:
 201                 raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 202                 gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
 203                         gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
 204                         & ~mpc_pin2mask(irqd_to_hwirq(d)));
 205                 raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 206                 break;
 207
 208         default:
 209                 return -EINVAL;
 210         }
 211
 212         return 0;
 213 }
 214
 215 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
 216 {
 217         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 218         struct gpio_chip *gc = &mpc8xxx_gc->gc;
 219         unsigned long gpio = irqd_to_hwirq(d);
 220         void __iomem *reg;
 221         unsigned int shift;
 222         unsigned long flags;
 223
 224         if (gpio < 16) {
 225                 reg = mpc8xxx_gc->regs + GPIO_ICR;
 226                 shift = (15 - gpio) * 2;
 227         } else {
 228                 reg = mpc8xxx_gc->regs + GPIO_ICR2;
 229                 shift = (15 - (gpio % 16)) * 2;
 230         }
 231
 232         switch (flow_type) {
 233         case IRQ_TYPE_EDGE_FALLING:
 234         case IRQ_TYPE_LEVEL_LOW:
 235                 raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 236                 gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
 237                         | (2 << shift));
 238                 raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 239                 break;
 240
 241         case IRQ_TYPE_EDGE_RISING:
 242         case IRQ_TYPE_LEVEL_HIGH:
 243                 raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 244                 gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
 245                         | (1 << shift));
 246                 raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 247                 break;
 248
 249         case IRQ_TYPE_EDGE_BOTH:
 250                 raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 251                 gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift)));
 252                 raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 253                 break;
 254
 255         default:
 256                 return -EINVAL;
 257         }
 258
 259         return 0;
 260 }
 261
 262 static struct irq_chip mpc8xxx_irq_chip = {
 263         .name           = "mpc8xxx-gpio",
 264         .irq_unmask     = mpc8xxx_irq_unmask,
 265         .irq_mask       = mpc8xxx_irq_mask,
 266         .irq_ack        = mpc8xxx_irq_ack,
 267         /* this might get overwritten in mpc8xxx_probe() */
 268         .irq_set_type   = mpc8xxx_irq_set_type,
 269 };
 270
 271 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
 272                                 irq_hw_number_t hwirq)
 273 {
 274         irq_set_chip_data(irq, h->host_data);
 275         irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_edge_irq);
 276
 277         return 0;
 278 }
 279
 280 static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
 281         .map    = mpc8xxx_gpio_irq_map,
 282         .xlate  = irq_domain_xlate_twocell,
 283 };
 284
 285 struct mpc8xxx_gpio_devtype {
 286         int (*gpio_dir_in_init)(struct gpio_chip *chip);
 287         int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
 288         int (*gpio_get)(struct gpio_chip *, unsigned int);
 289         int (*irq_set_type)(struct irq_data *, unsigned int);
 290 };
 291
 292 static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
 293         .gpio_dir_out = mpc5121_gpio_dir_out,
 294         .irq_set_type = mpc512x_irq_set_type,
 295 };
 296
 297 static const struct mpc8xxx_gpio_devtype ls1028a_gpio_devtype = {
 298         .gpio_dir_in_init = ls1028a_gpio_dir_in_init,
 299 };
 300
 301 static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
 302         .gpio_dir_out = mpc5125_gpio_dir_out,
 303         .irq_set_type = mpc512x_irq_set_type,
 304 };
 305
 306 static const struct mpc8xxx_gpio_devtype mpc8572_gpio_devtype = {
 307         .gpio_get = mpc8572_gpio_get,
 308 };
 309
 310 static const struct mpc8xxx_gpio_devtype mpc8xxx_gpio_devtype_default = {
 311         .irq_set_type = mpc8xxx_irq_set_type,
 312 };
 313
 314 static const struct of_device_id mpc8xxx_gpio_ids[] = {
 315         { .compatible = "fsl,mpc8349-gpio", },
 316         { .compatible = "fsl,mpc8572-gpio", .data = &mpc8572_gpio_devtype, },
 317         { .compatible = "fsl,mpc8610-gpio", },
 318         { .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
 319         { .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
 320         { .compatible = "fsl,pq3-gpio",     },
 321         { .compatible = "fsl,ls1028a-gpio", .data = &ls1028a_gpio_devtype, },
 322         { .compatible = "fsl,ls1088a-gpio", .data = &ls1028a_gpio_devtype, },
 323         { .compatible = "fsl,qoriq-gpio",   },
 324         {}
 325 };
 326
 327 static int mpc8xxx_probe(struct platform_device *pdev)
 328 {
 329         struct device_node *np = pdev->dev.of_node;
 330         struct mpc8xxx_gpio_chip *mpc8xxx_gc;
 331         struct gpio_chip        *gc;
 332         const struct mpc8xxx_gpio_devtype *devtype =
 333                 of_device_get_match_data(&pdev->dev);
 334         int ret;
 335
 336         mpc8xxx_gc = devm_kzalloc(&pdev->dev, sizeof(*mpc8xxx_gc), GFP_KERNEL);
 337         if (!mpc8xxx_gc)
 338                 return -ENOMEM;
 339
 340         platform_set_drvdata(pdev, mpc8xxx_gc);
 341
 342         raw_spin_lock_init(&mpc8xxx_gc->lock);
 343
 344         mpc8xxx_gc->regs = of_iomap(np, 0);
 345         if (!mpc8xxx_gc->regs)
 346                 return -ENOMEM;
 347
 348         gc = &mpc8xxx_gc->gc;
 349
 350         if (of_property_read_bool(np, "little-endian")) {
 351                 ret = bgpio_init(gc, &pdev->dev, 4,
 352                                  mpc8xxx_gc->regs + GPIO_DAT,
 353                                  NULL, NULL,
 354                                  mpc8xxx_gc->regs + GPIO_DIR, NULL,
 355                                  BGPIOF_BIG_ENDIAN);
 356                 if (ret)
 357                         goto err;
 358                 dev_dbg(&pdev->dev, "GPIO registers are LITTLE endian\n");
 359         } else {
 360                 ret = bgpio_init(gc, &pdev->dev, 4,
 361                                  mpc8xxx_gc->regs + GPIO_DAT,
 362                                  NULL, NULL,
 363                                  mpc8xxx_gc->regs + GPIO_DIR, NULL,
 364                                  BGPIOF_BIG_ENDIAN
 365                                  | BGPIOF_BIG_ENDIAN_BYTE_ORDER);
 366                 if (ret)
 367                         goto err;
 368                 dev_dbg(&pdev->dev, "GPIO registers are BIG endian\n");
 369         }
 370
 371         mpc8xxx_gc->direction_output = gc->direction_output;
 372
 373         if (!devtype)
 374                 devtype = &mpc8xxx_gpio_devtype_default;
 375
 376         /*
 377          * It's assumed that only a single type of gpio controller is available
 378          * on the current machine, so overwriting global data is fine.
 379          */
 380         if (devtype->irq_set_type)
 381                 mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type;
 382
 383         if (devtype->gpio_dir_out)
 384                 gc->direction_output = devtype->gpio_dir_out;
 385         if (devtype->gpio_get)
 386                 gc->get = devtype->gpio_get;
 387
 388         gc->to_irq = mpc8xxx_gpio_to_irq;
 389
 390         if (of_device_is_compatible(np, "fsl,qoriq-gpio"))
 391                 gc->write_reg(mpc8xxx_gc->regs + GPIO_IBE, 0xffffffff);
 392
 393         ret = gpiochip_add_data(gc, mpc8xxx_gc);
 394         if (ret) {
 395                 pr_err("%pOF: GPIO chip registration failed with status %d\n",
 396                        np, ret);
 397                 goto err;
 398         }
 399
 400         mpc8xxx_gc->irqn = irq_of_parse_and_map(np, 0);
 401         if (!mpc8xxx_gc->irqn)
 402                 return 0;
 403
 404         mpc8xxx_gc->irq = irq_domain_add_linear(np, MPC8XXX_GPIO_PINS,
 405                                         &mpc8xxx_gpio_irq_ops, mpc8xxx_gc);
 406         if (!mpc8xxx_gc->irq)
 407                 return 0;
 408
 409         /* ack and mask all irqs */
 410         gc->write_reg(mpc8xxx_gc->regs + GPIO_IER, 0xffffffff);
 411         gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR, 0);
 412         /* enable input buffer  */
 413         if (devtype->gpio_dir_in_init)
 414                 devtype->gpio_dir_in_init(gc);
 415
 416         ret = devm_request_irq(&pdev->dev, mpc8xxx_gc->irqn,
 417                                mpc8xxx_gpio_irq_cascade,
 418                                IRQF_NO_THREAD | IRQF_SHARED, "gpio-cascade",
 419                                mpc8xxx_gc);
 420         if (ret) {
 421                 dev_err(&pdev->dev, "%s: failed to devm_request_irq(%d), ret = %d\n",
 422                         np->full_name, mpc8xxx_gc->irqn, ret);
 423                 goto err;
 424         }
 425
 426         return 0;
 427 err:
 428         iounmap(mpc8xxx_gc->regs);
 429         return ret;
 430 }
 431
 432 static int mpc8xxx_remove(struct platform_device *pdev)
 433 {
 434         struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
 435
 436         if (mpc8xxx_gc->irq) {
 437                 irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, NULL, NULL);
 438                 irq_domain_remove(mpc8xxx_gc->irq);
 439         }
 440
 441         gpiochip_remove(&mpc8xxx_gc->gc);
 442         iounmap(mpc8xxx_gc->regs);
 443
 444         return 0;
 445 }
 446
 447 static struct platform_driver mpc8xxx_plat_driver = {
 448         .probe          = mpc8xxx_probe,
 449         .remove         = mpc8xxx_remove,
 450         .driver         = {
 451                 .name = "gpio-mpc8xxx",
 452                 .of_match_table = mpc8xxx_gpio_ids,
 453         },
 454 };
 455
 456 static int __init mpc8xxx_init(void)
 457 {
 458         return platform_driver_register(&mpc8xxx_plat_driver);
 459 }
 460
 461 arch_initcall(mpc8xxx_init);