historical/m0-applesillicon.git/xnu-qemu-arm64-5.1.0/roms/skiboot/hw/ec/gpio.c
2024-01-16 11:20:27 -06:00

87 lines
2.2 KiB
C

/* Copyright 2013-2014 Google Corp.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdint.h>
#include "ec/config.h"
#include "ec/gpio.h"
int ec_gpio_setup(EcGpioPort port, uint8_t pin,
int is_output, int pullup_enable)
{
uint8_t ddr_reg;
if (pin > 7) {
return -1;
}
/* Set data direction */
ec_outb(EC_GPIO_INDEX,
port * EC_GPIO_PORT_SKIP + EC_GPIO_DDR_OFFSET);
ddr_reg = ec_inb(EC_GPIO_DATA);
if (is_output) {
ddr_reg |= (1 << pin);
} else {
ddr_reg &= ~(1 << pin);
}
ec_outb(EC_GPIO_DATA, ddr_reg);
/* Set pullup enable for output GPOs */
if (is_output)
{
uint8_t pup_reg;
ec_outb(EC_GPIO_INDEX,
port * EC_GPIO_PORT_SKIP + EC_GPIO_PUP_OFFSET);
pup_reg = ec_inb(EC_GPIO_DATA);
if (pullup_enable) {
pup_reg |= (1 << pin);
} else {
pup_reg &= ~(1 << pin);
}
ec_outb(EC_GPIO_DATA, pup_reg);
}
return 0;
}
int ec_gpio_read(EcGpioPort port, uint8_t pin)
{
uint8_t pin_reg;
if (pin > 7) {
return -1;
}
ec_outb(EC_GPIO_INDEX,
port * EC_GPIO_PORT_SKIP + EC_GPIO_PIN_OFFSET);
pin_reg = ec_inb(EC_GPIO_DATA);
return !!(pin_reg & (1 << pin));
}
int ec_gpio_set(EcGpioPort port, uint8_t pin, int val)
{
uint8_t data_reg;
if (pin > 7) {
return -1;
}
ec_outb(EC_GPIO_INDEX,
port * EC_GPIO_PORT_SKIP + EC_GPIO_DATA_OFFSET);
data_reg = ec_inb(EC_GPIO_DATA);
if (val) {
data_reg |= (1 << pin);
} else {
data_reg &= ~(1 << pin);
}
ec_outb(EC_GPIO_DATA, data_reg);
return 0;
}