+++ /dev/null
-/*
- * GPIO interface for IT8761E Super I/O chip
- *
- * Author: Denis Turischev <denis@compulab.co.il>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License 2 as published
- * by the Free Software Foundation.
- *
- * 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; see the file COPYING. If not, write to
- * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/io.h>
-#include <linux/errno.h>
-#include <linux/ioport.h>
-
-#include <linux/gpio.h>
-
-#define SIO_CHIP_ID 0x8761
-#define CHIP_ID_HIGH_BYTE 0x20
-#define CHIP_ID_LOW_BYTE 0x21
-
-static u8 ports[2] = { 0x2e, 0x4e };
-static u8 port;
-
-static DEFINE_SPINLOCK(sio_lock);
-
-#define GPIO_NAME "it8761-gpio"
-#define GPIO_BA_HIGH_BYTE 0x60
-#define GPIO_BA_LOW_BYTE 0x61
-#define GPIO_IOSIZE 4
-#define GPIO1X_IO 0xf0
-#define GPIO2X_IO 0xf1
-
-static u16 gpio_ba;
-
-static u8 read_reg(u8 addr, u8 port)
-{
- outb(addr, port);
- return inb(port + 1);
-}
-
-static void write_reg(u8 data, u8 addr, u8 port)
-{
- outb(addr, port);
- outb(data, port + 1);
-}
-
-static void enter_conf_mode(u8 port)
-{
- outb(0x87, port);
- outb(0x61, port);
- outb(0x55, port);
- outb((port == 0x2e) ? 0x55 : 0xaa, port);
-}
-
-static void exit_conf_mode(u8 port)
-{
- outb(0x2, port);
- outb(0x2, port + 1);
-}
-
-static void enter_gpio_mode(u8 port)
-{
- write_reg(0x2, 0x7, port);
-}
-
-static int it8761e_gpio_get(struct gpio_chip *gc, unsigned gpio_num)
-{
- u16 reg;
- u8 bit;
-
- bit = gpio_num % 8;
- reg = (gpio_num >= 8) ? gpio_ba + 1 : gpio_ba;
-
- return !!(inb(reg) & (1 << bit));
-}
-
-static int it8761e_gpio_direction_in(struct gpio_chip *gc, unsigned gpio_num)
-{
- u8 curr_dirs;
- u8 io_reg, bit;
-
- bit = gpio_num % 8;
- io_reg = (gpio_num >= 8) ? GPIO2X_IO : GPIO1X_IO;
-
- spin_lock(&sio_lock);
-
- enter_conf_mode(port);
- enter_gpio_mode(port);
-
- curr_dirs = read_reg(io_reg, port);
-
- if (curr_dirs & (1 << bit))
- write_reg(curr_dirs & ~(1 << bit), io_reg, port);
-
- exit_conf_mode(port);
-
- spin_unlock(&sio_lock);
- return 0;
-}
-
-static void it8761e_gpio_set(struct gpio_chip *gc,
- unsigned gpio_num, int val)
-{
- u8 curr_vals, bit;
- u16 reg;
-
- bit = gpio_num % 8;
- reg = (gpio_num >= 8) ? gpio_ba + 1 : gpio_ba;
-
- spin_lock(&sio_lock);
-
- curr_vals = inb(reg);
- if (val)
- outb(curr_vals | (1 << bit) , reg);
- else
- outb(curr_vals & ~(1 << bit), reg);
-
- spin_unlock(&sio_lock);
-}
-
-static int it8761e_gpio_direction_out(struct gpio_chip *gc,
- unsigned gpio_num, int val)
-{
- u8 curr_dirs, io_reg, bit;
-
- bit = gpio_num % 8;
- io_reg = (gpio_num >= 8) ? GPIO2X_IO : GPIO1X_IO;
-
- it8761e_gpio_set(gc, gpio_num, val);
-
- spin_lock(&sio_lock);
-
- enter_conf_mode(port);
- enter_gpio_mode(port);
-
- curr_dirs = read_reg(io_reg, port);
-
- if (!(curr_dirs & (1 << bit)))
- write_reg(curr_dirs | (1 << bit), io_reg, port);
-
- exit_conf_mode(port);
-
- spin_unlock(&sio_lock);
- return 0;
-}
-
-static struct gpio_chip it8761e_gpio_chip = {
- .label = GPIO_NAME,
- .owner = THIS_MODULE,
- .get = it8761e_gpio_get,
- .direction_input = it8761e_gpio_direction_in,
- .set = it8761e_gpio_set,
- .direction_output = it8761e_gpio_direction_out,
-};
-
-static int __init it8761e_gpio_init(void)
-{
- int i, id, err;
-
- /* chip and port detection */
- for (i = 0; i < ARRAY_SIZE(ports); i++) {
- spin_lock(&sio_lock);
- enter_conf_mode(ports[i]);
-
- id = (read_reg(CHIP_ID_HIGH_BYTE, ports[i]) << 8) +
- read_reg(CHIP_ID_LOW_BYTE, ports[i]);
-
- exit_conf_mode(ports[i]);
- spin_unlock(&sio_lock);
-
- if (id == SIO_CHIP_ID) {
- port = ports[i];
- break;
- }
- }
-
- if (!port)
- return -ENODEV;
-
- /* fetch GPIO base address */
- enter_conf_mode(port);
- enter_gpio_mode(port);
- gpio_ba = (read_reg(GPIO_BA_HIGH_BYTE, port) << 8) +
- read_reg(GPIO_BA_LOW_BYTE, port);
- exit_conf_mode(port);
-
- if (!request_region(gpio_ba, GPIO_IOSIZE, GPIO_NAME))
- return -EBUSY;
-
- it8761e_gpio_chip.base = -1;
- it8761e_gpio_chip.ngpio = 16;
-
- err = gpiochip_add(&it8761e_gpio_chip);
- if (err < 0)
- goto gpiochip_add_err;
-
- return 0;
-
-gpiochip_add_err:
- release_region(gpio_ba, GPIO_IOSIZE);
- gpio_ba = 0;
- return err;
-}
-
-static void __exit it8761e_gpio_exit(void)
-{
- if (gpio_ba) {
- gpiochip_remove(&it8761e_gpio_chip);
- release_region(gpio_ba, GPIO_IOSIZE);
- gpio_ba = 0;
- }
-}
-module_init(it8761e_gpio_init);
-module_exit(it8761e_gpio_exit);
-
-MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
-MODULE_DESCRIPTION("GPIO interface for IT8761E Super I/O chip");
-MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff