1 /* Copyright 2013-2014 Google Corp.
2 *
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
12 * implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 #include <stdint.h>
17 #include "ec/config.h"
18 #include "ec/gpio.h"
19
ec_gpio_setup(EcGpioPort port,uint8_t pin,int is_output,int pullup_enable)20 int ec_gpio_setup(EcGpioPort port, uint8_t pin,
21 int is_output, int pullup_enable)
22 {
23 uint8_t ddr_reg;
24 if (pin > 7) {
25 return -1;
26 }
27
28 /* Set data direction */
29 ec_outb(EC_GPIO_INDEX,
30 port * EC_GPIO_PORT_SKIP + EC_GPIO_DDR_OFFSET);
31 ddr_reg = ec_inb(EC_GPIO_DATA);
32 if (is_output) {
33 ddr_reg |= (1 << pin);
34 } else {
35 ddr_reg &= ~(1 << pin);
36 }
37 ec_outb(EC_GPIO_DATA, ddr_reg);
38
39 /* Set pullup enable for output GPOs */
40 if (is_output)
41 {
42 uint8_t pup_reg;
43 ec_outb(EC_GPIO_INDEX,
44 port * EC_GPIO_PORT_SKIP + EC_GPIO_PUP_OFFSET);
45 pup_reg = ec_inb(EC_GPIO_DATA);
46 if (pullup_enable) {
47 pup_reg |= (1 << pin);
48 } else {
49 pup_reg &= ~(1 << pin);
50 }
51 ec_outb(EC_GPIO_DATA, pup_reg);
52 }
53
54 return 0;
55 }
56
ec_gpio_read(EcGpioPort port,uint8_t pin)57 int ec_gpio_read(EcGpioPort port, uint8_t pin)
58 {
59 uint8_t pin_reg;
60 if (pin > 7) {
61 return -1;
62 }
63
64 ec_outb(EC_GPIO_INDEX,
65 port * EC_GPIO_PORT_SKIP + EC_GPIO_PIN_OFFSET);
66 pin_reg = ec_inb(EC_GPIO_DATA);
67 return !!(pin_reg & (1 << pin));
68 }
69
ec_gpio_set(EcGpioPort port,uint8_t pin,int val)70 int ec_gpio_set(EcGpioPort port, uint8_t pin, int val)
71 {
72 uint8_t data_reg;
73 if (pin > 7) {
74 return -1;
75 }
76
77 ec_outb(EC_GPIO_INDEX,
78 port * EC_GPIO_PORT_SKIP + EC_GPIO_DATA_OFFSET);
79 data_reg = ec_inb(EC_GPIO_DATA);
80 if (val) {
81 data_reg |= (1 << pin);
82 } else {
83 data_reg &= ~(1 << pin);
84 }
85 ec_outb(EC_GPIO_DATA, data_reg);
86 return 0;
87 }
88