arch/powerpc/sysdev/mpc8xxx_gpio.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 mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 136 {
 137         struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
 138         struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
 139
 140         if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
 141                 return irq_create_mapping(mpc8xxx_gc->irq, offset);
 142         else
 143                 return -ENXIO;
 144 }
 145
 146 static void mpc8xxx_gpio_irq_cascade(unsigned int irq, struct irq_desc *desc)
 147 {
 148         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
 149         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 150         unsigned int mask;
 151
 152         mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
 153         if (mask)
 154                 generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
 155                                                      32 - ffs(mask)));
 156 }
 157
 158 static void mpc8xxx_irq_unmask(struct irq_data *d)
 159 {
 160         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 161         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 162         unsigned long flags;
 163
 164         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 165
 166         setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 167
 168         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 169 }
 170
 171 static void mpc8xxx_irq_mask(struct irq_data *d)
 172 {
 173         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 174         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 175         unsigned long flags;
 176
 177         spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 178
 179         clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 180
 181         spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 182 }
 183
 184 static void mpc8xxx_irq_ack(struct irq_data *d)
 185 {
 186         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 187         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 188
 189         out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 190 }
 191
 192 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
 193 {
 194         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 195         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 196         unsigned long flags;
 197
 198         switch (flow_type) {
 199         case IRQ_TYPE_EDGE_FALLING:
 200                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 201                 setbits32(mm->regs + GPIO_ICR,
 202                           mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 203                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 204                 break;
 205
 206         case IRQ_TYPE_EDGE_BOTH:
 207                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 208                 clrbits32(mm->regs + GPIO_ICR,
 209                           mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
 210                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 211                 break;
 212
 213         default:
 214                 return -EINVAL;
 215         }
 216
 217         return 0;
 218 }
 219
 220 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
 221 {
 222         struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
 223         struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
 224         unsigned long gpio = irqd_to_hwirq(d);
 225         void __iomem *reg;
 226         unsigned int shift;
 227         unsigned long flags;
 228
 229         if (gpio < 16) {
 230                 reg = mm->regs + GPIO_ICR;
 231                 shift = (15 - gpio) * 2;
 232         } else {
 233                 reg = mm->regs + GPIO_ICR2;
 234                 shift = (15 - (gpio % 16)) * 2;
 235         }
 236
 237         switch (flow_type) {
 238         case IRQ_TYPE_EDGE_FALLING:
 239         case IRQ_TYPE_LEVEL_LOW:
 240                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 241                 clrsetbits_be32(reg, 3 << shift, 2 << shift);
 242                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 243                 break;
 244
 245         case IRQ_TYPE_EDGE_RISING:
 246         case IRQ_TYPE_LEVEL_HIGH:
 247                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 248                 clrsetbits_be32(reg, 3 << shift, 1 << shift);
 249                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 250                 break;
 251
 252         case IRQ_TYPE_EDGE_BOTH:
 253                 spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
 254                 clrbits32(reg, 3 << shift);
 255                 spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
 256                 break;
 257
 258         default:
 259                 return -EINVAL;
 260         }
 261
 262         return 0;
 263 }
 264
 265 static struct irq_chip mpc8xxx_irq_chip = {
 266         .name           = "mpc8xxx-gpio",
 267         .irq_unmask     = mpc8xxx_irq_unmask,
 268         .irq_mask       = mpc8xxx_irq_mask,
 269         .irq_ack        = mpc8xxx_irq_ack,
 270         .irq_set_type   = mpc8xxx_irq_set_type,
 271 };
 272
 273 static int mpc8xxx_gpio_irq_map(struct irq_host *h, unsigned int virq,
 274                                 irq_hw_number_t hw)
 275 {
 276         struct mpc8xxx_gpio_chip *mpc8xxx_gc = h->host_data;
 277
 278         if (mpc8xxx_gc->of_dev_id_data)
 279                 mpc8xxx_irq_chip.irq_set_type = mpc8xxx_gc->of_dev_id_data;
 280
 281         irq_set_chip_data(virq, h->host_data);
 282         irq_set_chip_and_handler(virq, &mpc8xxx_irq_chip, handle_level_irq);
 283         irq_set_irq_type(virq, IRQ_TYPE_NONE);
 284
 285         return 0;
 286 }
 287
 288 static int mpc8xxx_gpio_irq_xlate(struct irq_host *h, struct device_node *ct,
 289                                   const u32 *intspec, unsigned int intsize,
 290                                   irq_hw_number_t *out_hwirq,
 291                                   unsigned int *out_flags)
 292
 293 {
 294         /* interrupt sense values coming from the device tree equal either
 295          * EDGE_FALLING or EDGE_BOTH
 296          */
 297         *out_hwirq = intspec[0];
 298         *out_flags = intspec[1];
 299
 300         return 0;
 301 }
 302
 303 static struct irq_host_ops mpc8xxx_gpio_irq_ops = {
 304         .map    = mpc8xxx_gpio_irq_map,
 305         .xlate  = mpc8xxx_gpio_irq_xlate,
 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,qoriq-gpio",   },
 314         {}
 315 };
 316
 317 static void __init mpc8xxx_add_controller(struct device_node *np)
 318 {
 319         struct mpc8xxx_gpio_chip *mpc8xxx_gc;
 320         struct of_mm_gpio_chip *mm_gc;
 321         struct gpio_chip *gc;
 322         const struct of_device_id *id;
 323         unsigned hwirq;
 324         int ret;
 325
 326         mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL);
 327         if (!mpc8xxx_gc) {
 328                 ret = -ENOMEM;
 329                 goto err;
 330         }
 331
 332         spin_lock_init(&mpc8xxx_gc->lock);
 333
 334         mm_gc = &mpc8xxx_gc->mm_gc;
 335         gc = &mm_gc->gc;
 336
 337         mm_gc->save_regs = mpc8xxx_gpio_save_regs;
 338         gc->ngpio = MPC8XXX_GPIO_PINS;
 339         gc->direction_input = mpc8xxx_gpio_dir_in;
 340         gc->direction_output = mpc8xxx_gpio_dir_out;
 341         if (of_device_is_compatible(np, "fsl,mpc8572-gpio"))
 342                 gc->get = mpc8572_gpio_get;
 343         else
 344                 gc->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 =
 357                 irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, MPC8XXX_GPIO_PINS,
 358                                &mpc8xxx_gpio_irq_ops, MPC8XXX_GPIO_PINS);
 359         if (!mpc8xxx_gc->irq)
 360                 goto skip_irq;
 361
 362         id = of_match_node(mpc8xxx_gpio_ids, np);
 363         if (id)
 364                 mpc8xxx_gc->of_dev_id_data = id->data;
 365
 366         mpc8xxx_gc->irq->host_data = mpc8xxx_gc;
 367
 368         /* ack and mask all irqs */
 369         out_be32(mm_gc->regs + GPIO_IER, 0xffffffff);
 370         out_be32(mm_gc->regs + GPIO_IMR, 0);
 371
 372         irq_set_handler_data(hwirq, mpc8xxx_gc);
 373         irq_set_chained_handler(hwirq, mpc8xxx_gpio_irq_cascade);
 374
 375 skip_irq:
 376         return;
 377
 378 err:
 379         pr_err("%s: registration failed with status %d\n",
 380                np->full_name, ret);
 381         kfree(mpc8xxx_gc);
 382
 383         return;
 384 }
 385
 386 static int __init mpc8xxx_add_gpiochips(void)
 387 {
 388         struct device_node *np;
 389
 390         for_each_matching_node(np, mpc8xxx_gpio_ids)
 391                 mpc8xxx_add_controller(np);
 392
 393         return 0;
 394 }
 395 arch_initcall(mpc8xxx_add_gpiochips);