2 * Copyright (c) 2009 Wind River Systems, Inc.
3 * Tom Rix <Tom.Rix@windriver.com>
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of
8 * the License, or (at your option) any later version.
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.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
20 * This work is derived from the linux 2.6.27 kernel source
21 * To fetch, use the kernel repository
22 * git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
23 * Use the v2.6.27 tag.
25 * Below is the original's header including its copyright
27 * linux/arch/arm/plat-omap/gpio.c
29 * Support functions for OMAP GPIO
31 * Copyright (C) 2003-2005 Nokia Corporation
32 * Written by Juha Yrjölä <juha.yrjola@nokia.com>
34 * This program is free software; you can redistribute it and/or modify
35 * it under the terms of the GNU General Public License version 2 as
36 * published by the Free Software Foundation.
41 #include <asm/errno.h>
43 #define OMAP_GPIO_DIR_OUT 0
44 #define OMAP_GPIO_DIR_IN 1
46 static inline const struct gpio_bank *get_gpio_bank(int gpio)
48 return &omap_gpio_bank[gpio >> 5];
51 static inline int get_gpio_index(int gpio)
56 int gpio_is_valid(int gpio)
58 return (gpio >= 0) && (gpio < OMAP_MAX_GPIO);
61 static int check_gpio(int gpio)
63 if (!gpio_is_valid(gpio)) {
64 printf("ERROR : check_gpio: invalid GPIO %d\n", gpio);
70 static void _set_gpio_direction(const struct gpio_bank *bank, int gpio,
73 void *reg = bank->base;
76 switch (bank->method) {
77 case METHOD_GPIO_24XX:
92 * Get the direction of the GPIO by reading the GPIO_OE register
93 * corresponding to the specified bank.
95 static int _get_gpio_direction(const struct gpio_bank *bank, int gpio)
97 void *reg = bank->base;
100 switch (bank->method) {
101 case METHOD_GPIO_24XX:
108 v = __raw_readl(reg);
111 return OMAP_GPIO_DIR_IN;
113 return OMAP_GPIO_DIR_OUT;
116 static void _set_gpio_dataout(const struct gpio_bank *bank, int gpio,
119 void *reg = bank->base;
122 switch (bank->method) {
123 case METHOD_GPIO_24XX:
125 reg += OMAP_GPIO_SETDATAOUT;
127 reg += OMAP_GPIO_CLEARDATAOUT;
131 printf("omap3-gpio unknown bank method %s %d\n",
135 __raw_writel(l, reg);
139 * Set value of the specified gpio
141 int gpio_set_value(unsigned gpio, int value)
143 const struct gpio_bank *bank;
145 if (check_gpio(gpio) < 0)
147 bank = get_gpio_bank(gpio);
148 _set_gpio_dataout(bank, get_gpio_index(gpio), value);
154 * Get value of the specified gpio
156 int gpio_get_value(unsigned gpio)
158 const struct gpio_bank *bank;
162 if (check_gpio(gpio) < 0)
164 bank = get_gpio_bank(gpio);
166 switch (bank->method) {
167 case METHOD_GPIO_24XX:
168 input = _get_gpio_direction(bank, get_gpio_index(gpio));
170 case OMAP_GPIO_DIR_IN:
171 reg += OMAP_GPIO_DATAIN;
173 case OMAP_GPIO_DIR_OUT:
174 reg += OMAP_GPIO_DATAOUT;
183 return (__raw_readl(reg)
184 & (1 << get_gpio_index(gpio))) != 0;
188 * Set gpio direction as input
190 int gpio_direction_input(unsigned gpio)
192 const struct gpio_bank *bank;
194 if (check_gpio(gpio) < 0)
197 bank = get_gpio_bank(gpio);
198 _set_gpio_direction(bank, get_gpio_index(gpio), 1);
204 * Set gpio direction as output
206 int gpio_direction_output(unsigned gpio, int value)
208 const struct gpio_bank *bank;
210 if (check_gpio(gpio) < 0)
213 bank = get_gpio_bank(gpio);
214 _set_gpio_dataout(bank, get_gpio_index(gpio), value);
215 _set_gpio_direction(bank, get_gpio_index(gpio), 0);
221 * Request a gpio before using it.
223 * NOTE: Argument 'label' is unused.
225 int gpio_request(unsigned gpio, const char *label)
227 if (check_gpio(gpio) < 0)
234 * Reset and free the gpio after using it.
236 int gpio_free(unsigned gpio)