diff options
Diffstat (limited to 'drivers/gpio/s3c2440_gpio.c')
-rw-r--r-- | drivers/gpio/s3c2440_gpio.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/drivers/gpio/s3c2440_gpio.c b/drivers/gpio/s3c2440_gpio.c new file mode 100644 index 0000000..43bbf11 --- /dev/null +++ b/drivers/gpio/s3c2440_gpio.c @@ -0,0 +1,95 @@ +/* + * Copyright (C) 2012 + * Gabriel Huau <contact@huau-gabriel.fr> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ +#include <common.h> +#include <asm/arch/s3c2440.h> +#include <asm/gpio.h> +#include <asm/io.h> + +#define GPIO_INPUT 0x0 +#define GPIO_OUTPUT 0x1 + +/* 0x4 means that we want DAT and not CON register */ +#define GPIO_PORT(x) ((((x) >> 5) & 0x3) + 0x4) +#define GPIO_BIT(x) ((x) & 0x3f) + +/* + * It's how we calculate the full port address + * We have to get the number of the port + 1 (Port A is at 0x56000001 ...) + * We move it at the second digit, and finally we add 0x4 because we want + * to modify GPIO DAT and not CON + */ +#define GPIO_FULLPORT(x) (S3C24X0_GPIO_BASE | ((GPIO_PORT(gpio) + 1) << 1)) + +int gpio_set_value(unsigned gpio, int value) +{ + unsigned l = readl(GPIO_FULLPORT(gpio)); + unsigned bit; + unsigned port = GPIO_FULLPORT(gpio); + + /* + * All GPIO Port have a configuration on + * 2 bits excepted the first GPIO (A) which + * have only 1 bit of configuration. + */ + if (!GPIO_PORT(gpio)) + bit = (0x1 << GPIO_BIT(gpio)); + else + bit = (0x3 << GPIO_BIT(gpio)); + + if (value) + l |= bit; + else + l &= ~bit; + + return writel(port, l); +} + +int gpio_get_value(unsigned gpio) +{ + unsigned l = readl(GPIO_FULLPORT(gpio)); + + if (GPIO_PORT(gpio) == 0) /* PORT A */ + return (l >> GPIO_BIT(gpio)) & 0x1; + return (l >> GPIO_BIT(gpio)) & 0x3; +} + +int gpio_request(unsigned gpio, const char *label) +{ + return 0; +} + +int gpio_free(unsigned gpio) +{ + return 0; +} + +int gpio_direction_input(unsigned gpio) +{ + return writel(GPIO_FULLPORT(gpio), GPIO_INPUT << GPIO_BIT(gpio)); +} + +int gpio_direction_output(unsigned gpio, int value) +{ + writel(GPIO_FULLPORT(gpio), GPIO_OUTPUT << GPIO_BIT(gpio)); + return gpio_set_value(gpio, value); +} |