--- /dev/null
+/*
+ * it8761_gpio.c - 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 % 7;
+ reg = (gpio_num >= 7) ? 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 % 7;
+ io_reg = (gpio_num >= 7) ? 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 % 7;
+ reg = (gpio_num >= 7) ? 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 % 7;
+ io_reg = (gpio_num >= 7) ? 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 = 14;
+
+ 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");
git://ftp.safe.ca / safe / jmp / linux-2.6 / commitdiff