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);