drivers/gpio/gpio-mpc8xxx.c

   1 /*
   2  * GPIOs on MPC512x/8349/8572/8610 and compatible
   3  *
   4  * Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
   5  *
   6  * This file is licensed under the terms of the GNU General Public License
   7  * version 2.  This program is licensed "as is" without any warranty of any
   8  * kind, whether express or implied.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/io.h>
  15 #include <linux/of.h>
  16 #include <linux/of_gpio.h>
  17 #include <linux/gpio.h>
  18 #include <linux/slab.h>
  19 #include <linux/irq.h>
  20
  21 #define MPC8XXX_GPIO_PINS       32
  22
  23 #define GPIO_DIR                0x00
  24 #define GPIO_ODR                0x04
  25 #define GPIO_DAT                0x08
  26 #define GPIO_IER                0x0c
  27 #define GPIO_IMR                0x10
  28 #define GPIO_ICR                0x14
  29 #define GPIO_ICR2               0x18
  30
  31 struct mpc8xxx_gpio_chip {
  32         struct of_mm_gpio_chip mm_gc;
  33         spinlock_t lock;
  34
  35         /*
  36          * shadowed data register to be able to clear/set output pins in
  37          * open drain mode safely
  38          */
  39         u32 data;
  40         struct irq_domain *irq;
  41         const void *of_dev_id_data;
  42 };
  43
  44 static inline u32 mpc8xxx_gpio2mask(unsigned int gpio)
  45 {
  46         return 1u << (MPC8XXX_GPIO_PINS - 1 - gpio);
  47 }
  48
  49 static inline struct mpc8xxx_gpio_chip *
  50 to_mpc8xxx_gpio_chip(struct of_mm_gpio_chip *mm)
  51 {
  52         return container_of(mm, struct mpc8xxx_gpio_chip, mm_gc);
  53 }
  54
  55 static void mpc8xxx_gpio_save_regs(struct of_mm_gpio_chip *mm)
  56 {
  57         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
  58
  59         mpc8xxx_gc->data = in_be32(mm->regs + GPIO_DAT);
  60 }
  61
  62 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
  63  * defined as output cannot be determined by reading GPDAT register,
  64  * so we use shadow data register instead. The status of input pins
  65  * is determined by reading GPDAT register.
  66  */
  67 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
  68 {
  69         u32 val;
  70         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
  71         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
  72         u32 out_mask, out_shadow;
  73
  74         out_mask = in_be32(mm->regs + GPIO_DIR);
  75
  76         val = in_be32(mm->regs + GPIO_DAT) & ~out_mask;
  77         out_shadow = mpc8xxx_gc->data & out_mask;
  78
  79         return (val | out_shadow) & mpc8xxx_gpio2mask(gpio);
  80 }
  81
  82 static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
  83 {
  84         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
  85
  86         return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
  87 }
  88
  89 static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
  90 {
  91         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
  92         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
  93         unsigned long flags;
  94
  95         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
  96
  97         if (val)
  98                 mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio);
  99         else
 100                 mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio);
 101
 102         out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
 103
 104         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 105 }
 106
 107 static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 108 {
 109         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
 110         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
 111         unsigned long flags;
 112
 113         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 114
 115         clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
 116
 117         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 118
 119         return 0;
 120 }
 121
 122 static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 123 {
 124         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
 125         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
 126         unsigned long flags;
 127
 128         mpc8xxx_gpio_set(gc, gpio, val);
 129
 130         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 131
 132         setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
 133
 134         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 135
 136         return 0;
 137 }
 138
 139 static int mpc5121_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 140 {
 141         /* GPIO 28..31 are input only on MPC5121 */
 142         if (gpio >= 28)
 143                 return -EINVAL;
 144
 145         return mpc8xxx_gpio_dir_out(gc, gpio, val);
 146 }
 147
 148 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 149 {
 150         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
 151         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
 152
 153         if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
 154                 return irq_create_mapping(mpc8xxx_gc->irq, offset);
 155         else
 156                 return -ENXIO;
 157 }
 158
 159 static void mpc8xxx_gpio_irq_cascade(unsigned int irq, struct irq_desc *desc)
 160 {
 161         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
 162         struct irq_chip *chip = irq_desc_get_chip(desc);
 163         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 164         unsigned int mask;
 165
 166         mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
 167         if (mask)
 168                 generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
 169                                                      32 - ffs(mask)));
 170         if (chip->irq_eoi)
 171                 chip->irq_eoi(&desc->irq_data);
 172 }
 173
 174 static void mpc8xxx_irq_unmask(struct irq_data *d)
 175 {
 176         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 177         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 178         unsigned long flags;
 179
 180         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 181
 182         setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 183
 184         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 185 }
 186
 187 static void mpc8xxx_irq_mask(struct irq_data *d)
 188 {
 189         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 190         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 191         unsigned long flags;
 192
 193         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 194
 195         clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 196
 197         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 198 }
 199
 200 static void mpc8xxx_irq_ack(struct irq_data *d)
 201 {
 202         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 203         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 204
 205         out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 206 }
 207
 208 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
 209 {
 210         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 211         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 212         unsigned long flags;
 213
 214         switch (flow_type) {
 215         case IRQ_TYPE_EDGE_FALLING:
 216                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 217                 setbits32(mm->regs + GPIO_ICR,
 218                           mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 219                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 220                 break;
 221
 222         case IRQ_TYPE_EDGE_BOTH:
 223                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 224                 clrbits32(mm->regs + GPIO_ICR,
 225                           mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 226                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 227                 break;
 228
 229         default:
 230                 return -EINVAL;
 231         }
 232
 233         return 0;
 234 }
 235
 236 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
 237 {
 238         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 239         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 240         unsigned long gpio = irqd_to_hwirq(d);
 241         void __iomem *reg;
 242         unsigned int shift;
 243         unsigned long flags;
 244
 245         if (gpio < 16) {
 246                 reg = mm->regs + GPIO_ICR;
 247                 shift = (15 - gpio) * 2;
 248         } else {
 249                 reg = mm->regs + GPIO_ICR2;
 250                 shift = (15 - (gpio % 16)) * 2;
 251         }
 252
 253         switch (flow_type) {
 254         case IRQ_TYPE_EDGE_FALLING:
 255         case IRQ_TYPE_LEVEL_LOW:
 256                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 257                 clrsetbits_be32(reg, 3 << shift, 2 << shift);
 258                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 259                 break;
 260
 261         case IRQ_TYPE_EDGE_RISING:
 262         case IRQ_TYPE_LEVEL_HIGH:
 263                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 264                 clrsetbits_be32(reg, 3 << shift, 1 << shift);
 265                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 266                 break;
 267
 268         case IRQ_TYPE_EDGE_BOTH:
 269                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 270                 clrbits32(reg, 3 << shift);
 271                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 272                 break;
 273
 274         default:
 275                 return -EINVAL;
 276         }
 277
 278         return 0;
 279 }
 280
 281 static struct irq_chip mpc8xxx_irq_chip = {
 282         .name           = "mpc8xxx-gpio",
 283         .irq_unmask     = mpc8xxx_irq_unmask,
 284         .irq_mask       = mpc8xxx_irq_mask,
 285         .irq_ack        = mpc8xxx_irq_ack,
 286         .irq_set_type   = mpc8xxx_irq_set_type,
 287 };
 288
 289 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int virq,
 290                                 irq_hw_number_t hw)
 291 {
 292         struct mpc8xxx_gpio_chip *mpc8xxx_gc = h->host_data;
 293
 294         if (mpc8xxx_gc->of_dev_id_data)
 295                 mpc8xxx_irq_chip.irq_set_type = mpc8xxx_gc->of_dev_id_data;
 296
 297         irq_set_chip_data(virq, h->host_data);
 298         irq_set_chip_and_handler(virq, &mpc8xxx_irq_chip, handle_edge_irq);
 299
 300         return 0;
 301 }
 302
 303 static struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
 304         .map    = mpc8xxx_gpio_irq_map,
 305         .xlate  = irq_domain_xlate_twocell,
 306 };
 307
 308 static struct of_device_id mpc8xxx_gpio_ids[] __initdata = {
 309         { .compatible = "fsl,mpc8349-gpio", },
 310         { .compatible = "fsl,mpc8572-gpio", },
 311         { .compatible = "fsl,mpc8610-gpio", },
 312         { .compatible = "fsl,mpc5121-gpio", .data = mpc512x_irq_set_type, },
 313         { .compatible = "fsl,pq3-gpio",     },
 314         { .compatible = "fsl,qoriq-gpio",   },
 315         {}
 316 };
 317
 318 static void __init mpc8xxx_add_controller(struct device_node *np)
 319 {
 320         struct mpc8xxx_gpio_chip *mpc8xxx_gc;
 321         struct of_mm_gpio_chip *mm_gc;
 322         struct gpio_chip *gc;
 323         const struct of_device_id *id;
 324         unsigned hwirq;
 325         int ret;
 326
 327         mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL);
 328         if (!mpc8xxx_gc) {
 329                 ret = -ENOMEM;
 330                 goto err;
 331         }
 332
 333         spin_lock_init(&mpc8xxx_gc->lock);
 334
 335         mm_gc = &mpc8xxx_gc->mm_gc;
 336         gc = &mm_gc->gc;
 337
 338         mm_gc->save_regs = mpc8xxx_gpio_save_regs;
 339         gc->ngpio = MPC8XXX_GPIO_PINS;
 340         gc->direction_input = mpc8xxx_gpio_dir_in;
 341         gc->direction_output = of_device_is_compatible(np, "fsl,mpc5121-gpio") ?
 342                 mpc5121_gpio_dir_out : mpc8xxx_gpio_dir_out;
 343         gc->get = of_device_is_compatible(np, "fsl,mpc8572-gpio") ?
 344                 mpc8572_gpio_get : mpc8xxx_gpio_get;
 345         gc->set = mpc8xxx_gpio_set;
 346         gc->to_irq = mpc8xxx_gpio_to_irq;
 347
 348         ret = of_mm_gpiochip_add(np, mm_gc);
 349         if (ret)
 350                 goto err;
 351
 352         hwirq = irq_of_parse_and_map(np, 0);
 353         if (hwirq == NO_IRQ)
 354                 goto skip_irq;
 355
 356         mpc8xxx_gc->irq = irq_domain_add_linear(np, MPC8XXX_GPIO_PINS,
 357                                         &mpc8xxx_gpio_irq_ops, mpc8xxx_gc);
 358         if (!mpc8xxx_gc->irq)
 359                 goto skip_irq;
 360
 361         id = of_match_node(mpc8xxx_gpio_ids, np);
 362         if (id)
 363                 mpc8xxx_gc->of_dev_id_data = id->data;
 364
 365         /* ack and mask all irqs */
 366         out_be32(mm_gc->regs + GPIO_IER, 0xffffffff);
 367         out_be32(mm_gc->regs + GPIO_IMR, 0);
 368
 369         irq_set_handler_data(hwirq, mpc8xxx_gc);
 370         irq_set_chained_handler(hwirq, mpc8xxx_gpio_irq_cascade);
 371
 372 skip_irq:
 373         return;
 374
 375 err:
 376         pr_err("%s: registration failed with status %d\n",
 377                np->full_name, ret);
 378         kfree(mpc8xxx_gc);
 379
 380         return;
 381 }
 382
 383 static int __init mpc8xxx_add_gpiochips(void)
 384 {
 385         struct device_node *np;
 386
 387         for_each_matching_node(np, mpc8xxx_gpio_ids)
 388                 mpc8xxx_add_controller(np);
 389
 390         return 0;
 391 }
 392 arch_initcall(mpc8xxx_add_gpiochips);