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_host *irq;
  41         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
  73         val = in_be32(mm->regs + GPIO_DAT) & ~in_be32(mm->regs + GPIO_DIR);
  74
  75         return (val | mpc8xxx_gc->data) & mpc8xxx_gpio2mask(gpio);
  76 }
  77
  78 static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
  79 {
  80         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
  81
  82         return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
  83 }
  84
  85 static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
  86 {
  87         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
  88         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
  89         unsigned long flags;
  90
  91         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
  92
  93         if (val)
  94                 mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio);
  95         else
  96                 mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio);
  97
  98         out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
  99
 100         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 101 }
 102
 103 static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 104 {
 105         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
 106         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
 107         unsigned long flags;
 108
 109         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 110
 111         clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
 112
 113         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 114
 115         return 0;
 116 }
 117
 118 static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 119 {
 120         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
 121         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
 122         unsigned long flags;
 123
 124         mpc8xxx_gpio_set(gc, gpio, val);
 125
 126         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 127
 128         setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
 129
 130         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 131
 132         return 0;
 133 }
 134
 135 static int mpc5121_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 136 {
 137         /* GPIO 28..31 are input only on MPC5121 */
 138         if (gpio >= 28)
 139                 return -EINVAL;
 140
 141         return mpc8xxx_gpio_dir_out(gc, gpio, val);
 142 }
 143
 144 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 145 {
 146         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
 147         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
 148
 149         if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
 150                 return irq_create_mapping(mpc8xxx_gc->irq, offset);
 151         else
 152                 return -ENXIO;
 153 }
 154
 155 static void mpc8xxx_gpio_irq_cascade(unsigned int irq, struct irq_desc *desc)
 156 {
 157         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
 158         struct irq_chip *chip = irq_desc_get_chip(desc);
 159         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 160         unsigned int mask;
 161
 162         mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
 163         if (mask)
 164                 generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
 165                                                      32 - ffs(mask)));
 166         if (chip->irq_eoi)
 167                 chip->irq_eoi(&desc->irq_data);
 168 }
 169
 170 static void mpc8xxx_irq_unmask(struct irq_data *d)
 171 {
 172         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 173         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 174         unsigned long flags;
 175
 176         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 177
 178         setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 179
 180         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 181 }
 182
 183 static void mpc8xxx_irq_mask(struct irq_data *d)
 184 {
 185         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 186         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 187         unsigned long flags;
 188
 189         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 190
 191         clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 192
 193         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 194 }
 195
 196 static void mpc8xxx_irq_ack(struct irq_data *d)
 197 {
 198         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 199         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 200
 201         out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 202 }
 203
 204 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
 205 {
 206         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 207         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 208         unsigned long flags;
 209
 210         switch (flow_type) {
 211         case IRQ_TYPE_EDGE_FALLING:
 212                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 213                 setbits32(mm->regs + GPIO_ICR,
 214                           mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 215                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 216                 break;
 217
 218         case IRQ_TYPE_EDGE_BOTH:
 219                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 220                 clrbits32(mm->regs + GPIO_ICR,
 221                           mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 222                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 223                 break;
 224
 225         default:
 226                 return -EINVAL;
 227         }
 228
 229         return 0;
 230 }
 231
 232 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
 233 {
 234         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 235         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 236         unsigned long gpio = irqd_to_hwirq(d);
 237         void __iomem *reg;
 238         unsigned int shift;
 239         unsigned long flags;
 240
 241         if (gpio < 16) {
 242                 reg = mm->regs + GPIO_ICR;
 243                 shift = (15 - gpio) * 2;
 244         } else {
 245                 reg = mm->regs + GPIO_ICR2;
 246                 shift = (15 - (gpio % 16)) * 2;
 247         }
 248
 249         switch (flow_type) {
 250         case IRQ_TYPE_EDGE_FALLING:
 251         case IRQ_TYPE_LEVEL_LOW:
 252                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 253                 clrsetbits_be32(reg, 3 << shift, 2 << shift);
 254                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 255                 break;
 256
 257         case IRQ_TYPE_EDGE_RISING:
 258         case IRQ_TYPE_LEVEL_HIGH:
 259                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 260                 clrsetbits_be32(reg, 3 << shift, 1 << shift);
 261                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 262                 break;
 263
 264         case IRQ_TYPE_EDGE_BOTH:
 265                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 266                 clrbits32(reg, 3 << shift);
 267                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 268                 break;
 269
 270         default:
 271                 return -EINVAL;
 272         }
 273
 274         return 0;
 275 }
 276
 277 static struct irq_chip mpc8xxx_irq_chip = {
 278         .name           = "mpc8xxx-gpio",
 279         .irq_unmask     = mpc8xxx_irq_unmask,
 280         .irq_mask       = mpc8xxx_irq_mask,
 281         .irq_ack        = mpc8xxx_irq_ack,
 282         .irq_set_type   = mpc8xxx_irq_set_type,
 283 };
 284
 285 static int mpc8xxx_gpio_irq_map(struct irq_host *h, unsigned int virq,
 286                                 irq_hw_number_t hw)
 287 {
 288         struct mpc8xxx_gpio_chip *mpc8xxx_gc = h->host_data;
 289
 290         if (mpc8xxx_gc->of_dev_id_data)
 291                 mpc8xxx_irq_chip.irq_set_type = mpc8xxx_gc->of_dev_id_data;
 292
 293         irq_set_chip_data(virq, h->host_data);
 294         irq_set_chip_and_handler(virq, &mpc8xxx_irq_chip, handle_level_irq);
 295         irq_set_irq_type(virq, IRQ_TYPE_NONE);
 296
 297         return 0;
 298 }
 299
 300 static int mpc8xxx_gpio_irq_xlate(struct irq_host *h, struct device_node *ct,
 301                                   const u32 *intspec, unsigned int intsize,
 302                                   irq_hw_number_t *out_hwirq,
 303                                   unsigned int *out_flags)
 304
 305 {
 306         /* interrupt sense values coming from the device tree equal either
 307          * EDGE_FALLING or EDGE_BOTH
 308          */
 309         *out_hwirq = intspec[0];
 310         *out_flags = intspec[1];
 311
 312         return 0;
 313 }
 314
 315 static struct irq_host_ops mpc8xxx_gpio_irq_ops = {
 316         .map    = mpc8xxx_gpio_irq_map,
 317         .xlate  = mpc8xxx_gpio_irq_xlate,
 318 };
 319
 320 static struct of_device_id mpc8xxx_gpio_ids[] __initdata = {
 321         { .compatible = "fsl,mpc8349-gpio", },
 322         { .compatible = "fsl,mpc8572-gpio", },
 323         { .compatible = "fsl,mpc8610-gpio", },
 324         { .compatible = "fsl,mpc5121-gpio", .data = mpc512x_irq_set_type, },
 325         { .compatible = "fsl,pq3-gpio",     },
 326         { .compatible = "fsl,qoriq-gpio",   },
 327         {}
 328 };
 329
 330 static void __init mpc8xxx_add_controller(struct device_node *np)
 331 {
 332         struct mpc8xxx_gpio_chip *mpc8xxx_gc;
 333         struct of_mm_gpio_chip *mm_gc;
 334         struct gpio_chip *gc;
 335         const struct of_device_id *id;
 336         unsigned hwirq;
 337         int ret;
 338
 339         mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL);
 340         if (!mpc8xxx_gc) {
 341                 ret = -ENOMEM;
 342                 goto err;
 343         }
 344
 345         spin_lock_init(&mpc8xxx_gc->lock);
 346
 347         mm_gc = &mpc8xxx_gc->mm_gc;
 348         gc = &mm_gc->gc;
 349
 350         mm_gc->save_regs = mpc8xxx_gpio_save_regs;
 351         gc->ngpio = MPC8XXX_GPIO_PINS;
 352         gc->direction_input = mpc8xxx_gpio_dir_in;
 353         gc->direction_output = of_device_is_compatible(np, "fsl,mpc5121-gpio") ?
 354                 mpc5121_gpio_dir_out : mpc8xxx_gpio_dir_out;
 355         gc->get = of_device_is_compatible(np, "fsl,mpc8572-gpio") ?
 356                 mpc8572_gpio_get : mpc8xxx_gpio_get;
 357         gc->set = mpc8xxx_gpio_set;
 358         gc->to_irq = mpc8xxx_gpio_to_irq;
 359
 360         ret = of_mm_gpiochip_add(np, mm_gc);
 361         if (ret)
 362                 goto err;
 363
 364         hwirq = irq_of_parse_and_map(np, 0);
 365         if (hwirq == NO_IRQ)
 366                 goto skip_irq;
 367
 368         mpc8xxx_gc->irq =
 369                 irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, MPC8XXX_GPIO_PINS,
 370                                &mpc8xxx_gpio_irq_ops, MPC8XXX_GPIO_PINS);
 371         if (!mpc8xxx_gc->irq)
 372                 goto skip_irq;
 373
 374         id = of_match_node(mpc8xxx_gpio_ids, np);
 375         if (id)
 376                 mpc8xxx_gc->of_dev_id_data = id->data;
 377
 378         mpc8xxx_gc->irq->host_data = mpc8xxx_gc;
 379
 380         /* ack and mask all irqs */
 381         out_be32(mm_gc->regs + GPIO_IER, 0xffffffff);
 382         out_be32(mm_gc->regs + GPIO_IMR, 0);
 383
 384         irq_set_handler_data(hwirq, mpc8xxx_gc);
 385         irq_set_chained_handler(hwirq, mpc8xxx_gpio_irq_cascade);
 386
 387 skip_irq:
 388         return;
 389
 390 err:
 391         pr_err("%s: registration failed with status %d\n",
 392                np->full_name, ret);
 393         kfree(mpc8xxx_gc);
 394
 395         return;
 396 }
 397
 398 static int __init mpc8xxx_add_gpiochips(void)
 399 {
 400         struct device_node *np;
 401
 402         for_each_matching_node(np, mpc8xxx_gpio_ids)
 403                 mpc8xxx_add_controller(np);
 404
 405         return 0;
 406 }
 407 arch_initcall(mpc8xxx_add_gpiochips);