linux/arch/arm/mach-msm/gpio.c
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   1/* linux/arch/arm/mach-msm/gpio.c
   2 *
   3 * Copyright (C) 2007 Google, Inc.
   4 * Copyright (c) 2009-2010, Code Aurora Forum. All rights reserved.
   5 *
   6 * This software is licensed under the terms of the GNU General Public
   7 * License version 2, as published by the Free Software Foundation, and
   8 * may be copied, distributed, and modified under those terms.
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 */
  16
  17#include <linux/bitops.h>
  18#include <linux/gpio.h>
  19#include <linux/interrupt.h>
  20#include <linux/io.h>
  21#include <linux/irq.h>
  22#include <linux/module.h>
  23#include "gpio_hw.h"
  24#include "gpiomux.h"
  25
  26#define FIRST_GPIO_IRQ MSM_GPIO_TO_INT(0)
  27
  28#define MSM_GPIO_BANK(bank, first, last)                                \
  29        {                                                               \
  30                .regs = {                                               \
  31                        .out =         MSM_GPIO_OUT_##bank,             \
  32                        .in =          MSM_GPIO_IN_##bank,              \
  33                        .int_status =  MSM_GPIO_INT_STATUS_##bank,      \
  34                        .int_clear =   MSM_GPIO_INT_CLEAR_##bank,       \
  35                        .int_en =      MSM_GPIO_INT_EN_##bank,          \
  36                        .int_edge =    MSM_GPIO_INT_EDGE_##bank,        \
  37                        .int_pos =     MSM_GPIO_INT_POS_##bank,         \
  38                        .oe =          MSM_GPIO_OE_##bank,              \
  39                },                                                      \
  40                .chip = {                                               \
  41                        .base = (first),                                \
  42                        .ngpio = (last) - (first) + 1,                  \
  43                        .get = msm_gpio_get,                            \
  44                        .set = msm_gpio_set,                            \
  45                        .direction_input = msm_gpio_direction_input,    \
  46                        .direction_output = msm_gpio_direction_output,  \
  47                        .to_irq = msm_gpio_to_irq,                      \
  48                        .request = msm_gpio_request,                    \
  49                        .free = msm_gpio_free,                          \
  50                }                                                       \
  51        }
  52
  53#define MSM_GPIO_BROKEN_INT_CLEAR 1
  54
  55struct msm_gpio_regs {
  56        void __iomem *out;
  57        void __iomem *in;
  58        void __iomem *int_status;
  59        void __iomem *int_clear;
  60        void __iomem *int_en;
  61        void __iomem *int_edge;
  62        void __iomem *int_pos;
  63        void __iomem *oe;
  64};
  65
  66struct msm_gpio_chip {
  67        spinlock_t              lock;
  68        struct gpio_chip        chip;
  69        struct msm_gpio_regs    regs;
  70#if MSM_GPIO_BROKEN_INT_CLEAR
  71        unsigned                int_status_copy;
  72#endif
  73        unsigned int            both_edge_detect;
  74        unsigned int            int_enable[2]; /* 0: awake, 1: sleep */
  75};
  76
  77static int msm_gpio_write(struct msm_gpio_chip *msm_chip,
  78                          unsigned offset, unsigned on)
  79{
  80        unsigned mask = BIT(offset);
  81        unsigned val;
  82
  83        val = readl(msm_chip->regs.out);
  84        if (on)
  85                writel(val | mask, msm_chip->regs.out);
  86        else
  87                writel(val & ~mask, msm_chip->regs.out);
  88        return 0;
  89}
  90
  91static void msm_gpio_update_both_edge_detect(struct msm_gpio_chip *msm_chip)
  92{
  93        int loop_limit = 100;
  94        unsigned pol, val, val2, intstat;
  95        do {
  96                val = readl(msm_chip->regs.in);
  97                pol = readl(msm_chip->regs.int_pos);
  98                pol = (pol & ~msm_chip->both_edge_detect) |
  99                      (~val & msm_chip->both_edge_detect);
 100                writel(pol, msm_chip->regs.int_pos);
 101                intstat = readl(msm_chip->regs.int_status);
 102                val2 = readl(msm_chip->regs.in);
 103                if (((val ^ val2) & msm_chip->both_edge_detect & ~intstat) == 0)
 104                        return;
 105        } while (loop_limit-- > 0);
 106        printk(KERN_ERR "msm_gpio_update_both_edge_detect, "
 107               "failed to reach stable state %x != %x\n", val, val2);
 108}
 109
 110static int msm_gpio_clear_detect_status(struct msm_gpio_chip *msm_chip,
 111                                        unsigned offset)
 112{
 113        unsigned bit = BIT(offset);
 114
 115#if MSM_GPIO_BROKEN_INT_CLEAR
 116        /* Save interrupts that already triggered before we loose them. */
 117        /* Any interrupt that triggers between the read of int_status */
 118        /* and the write to int_clear will still be lost though. */
 119        msm_chip->int_status_copy |= readl(msm_chip->regs.int_status);
 120        msm_chip->int_status_copy &= ~bit;
 121#endif
 122        writel(bit, msm_chip->regs.int_clear);
 123        msm_gpio_update_both_edge_detect(msm_chip);
 124        return 0;
 125}
 126
 127static int msm_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 128{
 129        struct msm_gpio_chip *msm_chip;
 130        unsigned long irq_flags;
 131
 132        msm_chip = container_of(chip, struct msm_gpio_chip, chip);
 133        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 134        writel(readl(msm_chip->regs.oe) & ~BIT(offset), msm_chip->regs.oe);
 135        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 136        return 0;
 137}
 138
 139static int
 140msm_gpio_direction_output(struct gpio_chip *chip, unsigned offset, int value)
 141{
 142        struct msm_gpio_chip *msm_chip;
 143        unsigned long irq_flags;
 144
 145        msm_chip = container_of(chip, struct msm_gpio_chip, chip);
 146        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 147        msm_gpio_write(msm_chip, offset, value);
 148        writel(readl(msm_chip->regs.oe) | BIT(offset), msm_chip->regs.oe);
 149        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 150        return 0;
 151}
 152
 153static int msm_gpio_get(struct gpio_chip *chip, unsigned offset)
 154{
 155        struct msm_gpio_chip *msm_chip;
 156
 157        msm_chip = container_of(chip, struct msm_gpio_chip, chip);
 158        return (readl(msm_chip->regs.in) & (1U << offset)) ? 1 : 0;
 159}
 160
 161static void msm_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 162{
 163        struct msm_gpio_chip *msm_chip;
 164        unsigned long irq_flags;
 165
 166        msm_chip = container_of(chip, struct msm_gpio_chip, chip);
 167        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 168        msm_gpio_write(msm_chip, offset, value);
 169        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 170}
 171
 172static int msm_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 173{
 174        return MSM_GPIO_TO_INT(chip->base + offset);
 175}
 176
 177#ifdef CONFIG_MSM_GPIOMUX
 178static int msm_gpio_request(struct gpio_chip *chip, unsigned offset)
 179{
 180        return msm_gpiomux_get(chip->base + offset);
 181}
 182
 183static void msm_gpio_free(struct gpio_chip *chip, unsigned offset)
 184{
 185        msm_gpiomux_put(chip->base + offset);
 186}
 187#else
 188#define msm_gpio_request NULL
 189#define msm_gpio_free NULL
 190#endif
 191
 192struct msm_gpio_chip msm_gpio_chips[] = {
 193#if defined(CONFIG_ARCH_MSM7X00A)
 194        MSM_GPIO_BANK(0,   0,  15),
 195        MSM_GPIO_BANK(1,  16,  42),
 196        MSM_GPIO_BANK(2,  43,  67),
 197        MSM_GPIO_BANK(3,  68,  94),
 198        MSM_GPIO_BANK(4,  95, 106),
 199        MSM_GPIO_BANK(5, 107, 121),
 200#elif defined(CONFIG_ARCH_MSM7X25) || defined(CONFIG_ARCH_MSM7X27)
 201        MSM_GPIO_BANK(0,   0,  15),
 202        MSM_GPIO_BANK(1,  16,  42),
 203        MSM_GPIO_BANK(2,  43,  67),
 204        MSM_GPIO_BANK(3,  68,  94),
 205        MSM_GPIO_BANK(4,  95, 106),
 206        MSM_GPIO_BANK(5, 107, 132),
 207#elif defined(CONFIG_ARCH_MSM7X30)
 208        MSM_GPIO_BANK(0,   0,  15),
 209        MSM_GPIO_BANK(1,  16,  43),
 210        MSM_GPIO_BANK(2,  44,  67),
 211        MSM_GPIO_BANK(3,  68,  94),
 212        MSM_GPIO_BANK(4,  95, 106),
 213        MSM_GPIO_BANK(5, 107, 133),
 214        MSM_GPIO_BANK(6, 134, 150),
 215        MSM_GPIO_BANK(7, 151, 181),
 216#elif defined(CONFIG_ARCH_QSD8X50)
 217        MSM_GPIO_BANK(0,   0,  15),
 218        MSM_GPIO_BANK(1,  16,  42),
 219        MSM_GPIO_BANK(2,  43,  67),
 220        MSM_GPIO_BANK(3,  68,  94),
 221        MSM_GPIO_BANK(4,  95, 103),
 222        MSM_GPIO_BANK(5, 104, 121),
 223        MSM_GPIO_BANK(6, 122, 152),
 224        MSM_GPIO_BANK(7, 153, 164),
 225#endif
 226};
 227
 228static void msm_gpio_irq_ack(unsigned int irq)
 229{
 230        unsigned long irq_flags;
 231        struct msm_gpio_chip *msm_chip = get_irq_chip_data(irq);
 232        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 233        msm_gpio_clear_detect_status(msm_chip,
 234                                     irq - gpio_to_irq(msm_chip->chip.base));
 235        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 236}
 237
 238static void msm_gpio_irq_mask(unsigned int irq)
 239{
 240        unsigned long irq_flags;
 241        struct msm_gpio_chip *msm_chip = get_irq_chip_data(irq);
 242        unsigned offset = irq - gpio_to_irq(msm_chip->chip.base);
 243
 244        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 245        /* level triggered interrupts are also latched */
 246        if (!(readl(msm_chip->regs.int_edge) & BIT(offset)))
 247                msm_gpio_clear_detect_status(msm_chip, offset);
 248        msm_chip->int_enable[0] &= ~BIT(offset);
 249        writel(msm_chip->int_enable[0], msm_chip->regs.int_en);
 250        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 251}
 252
 253static void msm_gpio_irq_unmask(unsigned int irq)
 254{
 255        unsigned long irq_flags;
 256        struct msm_gpio_chip *msm_chip = get_irq_chip_data(irq);
 257        unsigned offset = irq - gpio_to_irq(msm_chip->chip.base);
 258
 259        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 260        /* level triggered interrupts are also latched */
 261        if (!(readl(msm_chip->regs.int_edge) & BIT(offset)))
 262                msm_gpio_clear_detect_status(msm_chip, offset);
 263        msm_chip->int_enable[0] |= BIT(offset);
 264        writel(msm_chip->int_enable[0], msm_chip->regs.int_en);
 265        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 266}
 267
 268static int msm_gpio_irq_set_wake(unsigned int irq, unsigned int on)
 269{
 270        unsigned long irq_flags;
 271        struct msm_gpio_chip *msm_chip = get_irq_chip_data(irq);
 272        unsigned offset = irq - gpio_to_irq(msm_chip->chip.base);
 273
 274        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 275
 276        if (on)
 277                msm_chip->int_enable[1] |= BIT(offset);
 278        else
 279                msm_chip->int_enable[1] &= ~BIT(offset);
 280
 281        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 282        return 0;
 283}
 284
 285static int msm_gpio_irq_set_type(unsigned int irq, unsigned int flow_type)
 286{
 287        unsigned long irq_flags;
 288        struct msm_gpio_chip *msm_chip = get_irq_chip_data(irq);
 289        unsigned offset = irq - gpio_to_irq(msm_chip->chip.base);
 290        unsigned val, mask = BIT(offset);
 291
 292        spin_lock_irqsave(&msm_chip->lock, irq_flags);
 293        val = readl(msm_chip->regs.int_edge);
 294        if (flow_type & IRQ_TYPE_EDGE_BOTH) {
 295                writel(val | mask, msm_chip->regs.int_edge);
 296                irq_desc[irq].handle_irq = handle_edge_irq;
 297        } else {
 298                writel(val & ~mask, msm_chip->regs.int_edge);
 299                irq_desc[irq].handle_irq = handle_level_irq;
 300        }
 301        if ((flow_type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
 302                msm_chip->both_edge_detect |= mask;
 303                msm_gpio_update_both_edge_detect(msm_chip);
 304        } else {
 305                msm_chip->both_edge_detect &= ~mask;
 306                val = readl(msm_chip->regs.int_pos);
 307                if (flow_type & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_HIGH))
 308                        writel(val | mask, msm_chip->regs.int_pos);
 309                else
 310                        writel(val & ~mask, msm_chip->regs.int_pos);
 311        }
 312        spin_unlock_irqrestore(&msm_chip->lock, irq_flags);
 313        return 0;
 314}
 315
 316static void msm_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
 317{
 318        int i, j, mask;
 319        unsigned val;
 320
 321        for (i = 0; i < ARRAY_SIZE(msm_gpio_chips); i++) {
 322                struct msm_gpio_chip *msm_chip = &msm_gpio_chips[i];
 323                val = readl(msm_chip->regs.int_status);
 324                val &= msm_chip->int_enable[0];
 325                while (val) {
 326                        mask = val & -val;
 327                        j = fls(mask) - 1;
 328                        /* printk("%s %08x %08x bit %d gpio %d irq %d\n",
 329                                __func__, v, m, j, msm_chip->chip.start + j,
 330                                FIRST_GPIO_IRQ + msm_chip->chip.start + j); */
 331                        val &= ~mask;
 332                        generic_handle_irq(FIRST_GPIO_IRQ +
 333                                           msm_chip->chip.base + j);
 334                }
 335        }
 336        desc->chip->ack(irq);
 337}
 338
 339static struct irq_chip msm_gpio_irq_chip = {
 340        .name      = "msmgpio",
 341        .ack       = msm_gpio_irq_ack,
 342        .mask      = msm_gpio_irq_mask,
 343        .unmask    = msm_gpio_irq_unmask,
 344        .set_wake  = msm_gpio_irq_set_wake,
 345        .set_type  = msm_gpio_irq_set_type,
 346};
 347
 348static int __init msm_init_gpio(void)
 349{
 350        int i, j = 0;
 351
 352        for (i = FIRST_GPIO_IRQ; i < FIRST_GPIO_IRQ + NR_GPIO_IRQS; i++) {
 353                if (i - FIRST_GPIO_IRQ >=
 354                        msm_gpio_chips[j].chip.base +
 355                        msm_gpio_chips[j].chip.ngpio)
 356                        j++;
 357                set_irq_chip_data(i, &msm_gpio_chips[j]);
 358                set_irq_chip(i, &msm_gpio_irq_chip);
 359                set_irq_handler(i, handle_edge_irq);
 360                set_irq_flags(i, IRQF_VALID);
 361        }
 362
 363        for (i = 0; i < ARRAY_SIZE(msm_gpio_chips); i++) {
 364                spin_lock_init(&msm_gpio_chips[i].lock);
 365                writel(0, msm_gpio_chips[i].regs.int_en);
 366                gpiochip_add(&msm_gpio_chips[i].chip);
 367        }
 368
 369        set_irq_chained_handler(INT_GPIO_GROUP1, msm_gpio_irq_handler);
 370        set_irq_chained_handler(INT_GPIO_GROUP2, msm_gpio_irq_handler);
 371        set_irq_wake(INT_GPIO_GROUP1, 1);
 372        set_irq_wake(INT_GPIO_GROUP2, 2);
 373        return 0;
 374}
 375
 376postcore_initcall(msm_init_gpio);
 377
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