LXR linux/arch/mips/loongson/common/gpio.c

   1/*
   2 *  STLS2F GPIO Support
   3 *
   4 *  Copyright (c) 2008 Richard Liu,  STMicroelectronics  <richard.liu@st.com>
   5 *  Copyright (c) 2008-2010 Arnaud Patard <apatard@mandriva.com>
   6 *
   7 *  This program is free software; you can redistribute it and/or modify
   8 *  it under the terms of the GNU General Public License as published by
   9 *  the Free Software Foundation; either version 2 of the License, or
  10 *  (at your option) any later version.
  11 */
  12
  13#include <linux/kernel.h>
  14#include <linux/init.h>
  15#include <linux/module.h>
  16#include <linux/spinlock.h>
  17#include <linux/err.h>
  18#include <asm/types.h>
  19#include <loongson.h>
  20#include <linux/gpio.h>
  21
  22#define STLS2F_N_GPIO           4
  23#define STLS2F_GPIO_IN_OFFSET   16
  24
  25static DEFINE_SPINLOCK(gpio_lock);
  26
  27int gpio_get_value(unsigned gpio)
  28{
  29        u32 val;
  30        u32 mask;
  31
  32        if (gpio >= STLS2F_N_GPIO)
  33                return __gpio_get_value(gpio);
  34
  35        mask = 1 << (gpio + STLS2F_GPIO_IN_OFFSET);
  36        spin_lock(&gpio_lock);
  37        val = LOONGSON_GPIODATA;
  38        spin_unlock(&gpio_lock);
  39
  40        return ((val & mask) != 0);
  41}
  42EXPORT_SYMBOL(gpio_get_value);
  43
  44void gpio_set_value(unsigned gpio, int state)
  45{
  46        u32 val;
  47        u32 mask;
  48
  49        if (gpio >= STLS2F_N_GPIO) {
  50                __gpio_set_value(gpio, state);
  51                return ;
  52        }
  53
  54        mask = 1 << gpio;
  55
  56        spin_lock(&gpio_lock);
  57        val = LOONGSON_GPIODATA;
  58        if (state)
  59                val |= mask;
  60        else
  61                val &= (~mask);
  62        LOONGSON_GPIODATA = val;
  63        spin_unlock(&gpio_lock);
  64}
  65EXPORT_SYMBOL(gpio_set_value);
  66
  67int gpio_cansleep(unsigned gpio)
  68{
  69        if (gpio < STLS2F_N_GPIO)
  70                return 0;
  71        else
  72                return __gpio_cansleep(gpio);
  73}
  74EXPORT_SYMBOL(gpio_cansleep);
  75
  76static int ls2f_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
  77{
  78        u32 temp;
  79        u32 mask;
  80
  81        if (gpio >= STLS2F_N_GPIO)
  82                return -EINVAL;
  83
  84        spin_lock(&gpio_lock);
  85        mask = 1 << gpio;
  86        temp = LOONGSON_GPIOIE;
  87        temp |= mask;
  88        LOONGSON_GPIOIE = temp;
  89        spin_unlock(&gpio_lock);
  90
  91        return 0;
  92}
  93
  94static int ls2f_gpio_direction_output(struct gpio_chip *chip,
  95                unsigned gpio, int level)
  96{
  97        u32 temp;
  98        u32 mask;
  99
 100        if (gpio >= STLS2F_N_GPIO)
 101                return -EINVAL;
 102
 103        gpio_set_value(gpio, level);
 104        spin_lock(&gpio_lock);
 105        mask = 1 << gpio;
 106        temp = LOONGSON_GPIOIE;
 107        temp &= (~mask);
 108        LOONGSON_GPIOIE = temp;
 109        spin_unlock(&gpio_lock);
 110
 111        return 0;
 112}
 113
 114static int ls2f_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
 115{
 116        return gpio_get_value(gpio);
 117}
 118
 119static void ls2f_gpio_set_value(struct gpio_chip *chip,
 120                unsigned gpio, int value)
 121{
 122        gpio_set_value(gpio, value);
 123}
 124
 125static struct gpio_chip ls2f_chip = {
 126        .label                  = "ls2f",
 127        .direction_input        = ls2f_gpio_direction_input,
 128        .get                    = ls2f_gpio_get_value,
 129        .direction_output       = ls2f_gpio_direction_output,
 130        .set                    = ls2f_gpio_set_value,
 131        .base                   = 0,
 132        .ngpio                  = STLS2F_N_GPIO,
 133};
 134
 135static int __init ls2f_gpio_setup(void)
 136{
 137        return gpiochip_add(&ls2f_chip);
 138}
 139arch_initcall(ls2f_gpio_setup);
 140