gpio.c

Go to the documentation of this file.

/* SPDX-License-Identifier: GPL-2.0-or-later */
 
#include <device/mmio.h>
#include <console/console.h>
#include <soc/ti/am335x/gpio.h>
#include <stdint.h>
 
static struct am335x_gpio_regs *gpio_regs_and_bit(unsigned int gpio,
                                                  uint32_t *bit)
{
        unsigned int bank = gpio / AM335X_GPIO_BITS_PER_BANK;
 
        if (bank >= ARRAY_SIZE(am335x_gpio_banks)) {
                printk(BIOS_ERR, "Bad gpio index %d.\n", gpio);
                return NULL;
        }
        *bit = 1 << (gpio % 32);
        return am335x_gpio_banks[bank];
}
 
void am335x_disable_gpio_irqs(void)
{
        int i;
 
        for (i = 0; i < ARRAY_SIZE(am335x_gpio_banks); i++)
                write32(&am335x_gpio_banks[i]->irqstatus_clr_0, 0xffffffff);
}
 
int gpio_direction_input(unsigned int gpio)
{
        uint32_t bit;
        struct am335x_gpio_regs *regs = gpio_regs_and_bit(gpio, &bit);
 
        if (!regs)
                return -1;
        setbits32(&regs->oe, bit);
        return 0;
}
 
int gpio_direction_output(unsigned int gpio, int value)
{
        uint32_t bit;
        struct am335x_gpio_regs *regs = gpio_regs_and_bit(gpio, &bit);
 
        if (!regs)
                return -1;
        if (value)
                write32(&regs->setdataout, bit);
        else
                write32(&regs->cleardataout, bit);
        clrbits32(&regs->oe, bit);
        return 0;
}
 
int gpio_get_value(unsigned int gpio)
{
        uint32_t bit;
        struct am335x_gpio_regs *regs = gpio_regs_and_bit(gpio, &bit);
 
        if (!regs)
                return -1;
        return (read32(&regs->datain) & bit) ? 1 : 0;
}
 
int gpio_set_value(unsigned int gpio, int value)
{
        uint32_t bit;
        struct am335x_gpio_regs *regs = gpio_regs_and_bit(gpio, &bit);
 
        if (!regs)
                return -1;
        if (value)
                write32(&regs->setdataout, bit);
        else
                write32(&regs->cleardataout, bit);
        return 0;
}