gpio: add GPIO support for IT87xx, replacing gpio-it8761e

This patch adds support for the GPIOs found on the ITE super-I/O chips
IT87xx.

Signed-off-by: Diego Elio Pettenò <flameeyes@flameeyes.eu>
Signed-off-by: Christophe Vu-Brugier <cvubrugier@fastmail.fm>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Diego Elio Pettenò 2015-09-21 18:24:24 +02:00 committed by Linus Walleij
parent 48b5953ed8
commit b8664924e8
4 changed files with 422 additions and 235 deletions

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@ -235,11 +235,17 @@ config GPIO_IOP
If unsure, say N.
config GPIO_IT8761E
tristate "IT8761E GPIO support"
depends on X86 # unconditional access to IO space.
config GPIO_IT87
tristate "IT87xx GPIO support"
depends on X86 # unconditional access to IO space.
help
Say yes here to support GPIO functionality of IT8761E super I/O chip.
Say yes here to support GPIO functionality of IT87xx Super I/O chips.
This driver is tested with ITE IT8728 and IT8732 Super I/O chips, and
supports the IT8761E Super I/O chip as well.
To compile this driver as a module, choose M here: the module will
be called gpio_it87
config GPIO_LOONGSON
bool "Loongson-2/3 GPIO support"

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@ -40,7 +40,7 @@ obj-$(CONFIG_GPIO_GE_FPGA) += gpio-ge.o
obj-$(CONFIG_GPIO_GRGPIO) += gpio-grgpio.o
obj-$(CONFIG_GPIO_ICH) += gpio-ich.o
obj-$(CONFIG_GPIO_IOP) += gpio-iop.o
obj-$(CONFIG_GPIO_IT8761E) += gpio-it8761e.o
obj-$(CONFIG_GPIO_IT87) += gpio-it87.o
obj-$(CONFIG_GPIO_JANZ_TTL) += gpio-janz-ttl.o
obj-$(CONFIG_GPIO_KEMPLD) += gpio-kempld.o
obj-$(CONFIG_ARCH_KS8695) += gpio-ks8695.o

411
drivers/gpio/gpio-it87.c Normal file
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@ -0,0 +1,411 @@
/*
* GPIO interface for IT87xx Super I/O chips
*
* Author: Diego Elio Pettenò <flameeyes@flameeyes.eu>
*
* Based on it87_wdt.c by Oliver Schuster
* gpio-it8761e.c by Denis Turischev
* gpio-stmpe.c by Rabin Vincent
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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/slab.h>
#include <linux/gpio.h>
/* Chip Id numbers */
#define NO_DEV_ID 0xffff
#define IT8728_ID 0x8728
#define IT8732_ID 0x8732
#define IT8761_ID 0x8761
/* IO Ports */
#define REG 0x2e
#define VAL 0x2f
/* Logical device Numbers LDN */
#define GPIO 0x07
/* Configuration Registers and Functions */
#define LDNREG 0x07
#define CHIPID 0x20
#define CHIPREV 0x22
/**
* struct it87_gpio - it87-specific GPIO chip
* @chip the underlying gpio_chip structure
* @lock a lock to avoid races between operations
* @io_base base address for gpio ports
* @io_size size of the port rage starting from io_base.
* @output_base Super I/O register address for Output Enable register
* @simple_base Super I/O 'Simple I/O' Enable register
* @simple_size Super IO 'Simple I/O' Enable register size; this is
* required because IT87xx chips might only provide Simple I/O
* switches on a subset of lines, whereas the others keep the
* same status all time.
*/
struct it87_gpio {
struct gpio_chip chip;
spinlock_t lock;
u16 io_base;
u16 io_size;
u8 output_base;
u8 simple_base;
u8 simple_size;
};
static struct it87_gpio it87_gpio_chip = {
.lock = __SPIN_LOCK_UNLOCKED(it87_gpio_chip.lock),
};
static inline struct it87_gpio *to_it87_gpio(struct gpio_chip *chip)
{
return container_of(chip, struct it87_gpio, chip);
}
/* Superio chip access functions; copied from wdt_it87 */
static inline int superio_enter(void)
{
/*
* Try to reserve REG and REG + 1 for exclusive access.
*/
if (!request_muxed_region(REG, 2, KBUILD_MODNAME))
return -EBUSY;
outb(0x87, REG);
outb(0x01, REG);
outb(0x55, REG);
outb(0x55, REG);
return 0;
}
static inline void superio_exit(void)
{
outb(0x02, REG);
outb(0x02, VAL);
release_region(REG, 2);
}
static inline void superio_select(int ldn)
{
outb(LDNREG, REG);
outb(ldn, VAL);
}
static inline int superio_inb(int reg)
{
outb(reg, REG);
return inb(VAL);
}
static inline void superio_outb(int val, int reg)
{
outb(reg, REG);
outb(val, VAL);
}
static inline int superio_inw(int reg)
{
int val;
outb(reg++, REG);
val = inb(VAL) << 8;
outb(reg, REG);
val |= inb(VAL);
return val;
}
static inline void superio_outw(int val, int reg)
{
outb(reg++, REG);
outb(val >> 8, VAL);
outb(reg, REG);
outb(val, VAL);
}
static inline void superio_set_mask(int mask, int reg)
{
u8 curr_val = superio_inb(reg);
u8 new_val = curr_val | mask;
if (curr_val != new_val)
superio_outb(new_val, reg);
}
static inline void superio_clear_mask(int mask, int reg)
{
u8 curr_val = superio_inb(reg);
u8 new_val = curr_val & ~mask;
if (curr_val != new_val)
superio_outb(new_val, reg);
}
static int it87_gpio_request(struct gpio_chip *chip, unsigned gpio_num)
{
u8 mask, group;
int rc = 0;
struct it87_gpio *it87_gpio = to_it87_gpio(chip);
mask = 1 << (gpio_num % 8);
group = (gpio_num / 8);
spin_lock(&it87_gpio->lock);
rc = superio_enter();
if (rc)
goto exit;
/* not all the IT87xx chips support Simple I/O and not all of
* them allow all the lines to be set/unset to Simple I/O.
*/
if (group < it87_gpio->simple_size)
superio_set_mask(mask, group + it87_gpio->simple_base);
/* clear output enable, setting the pin to input, as all the
* newly-exported GPIO interfaces are set to input.
*/
superio_clear_mask(mask, group + it87_gpio->output_base);
superio_exit();
exit:
spin_unlock(&it87_gpio->lock);
return rc;
}
static int it87_gpio_get(struct gpio_chip *chip, unsigned gpio_num)
{
u16 reg;
u8 mask;
struct it87_gpio *it87_gpio = to_it87_gpio(chip);
mask = 1 << (gpio_num % 8);
reg = (gpio_num / 8) + it87_gpio->io_base;
return !!(inb(reg) & mask);
}
static int it87_gpio_direction_in(struct gpio_chip *chip, unsigned gpio_num)
{
u8 mask, group;
int rc = 0;
struct it87_gpio *it87_gpio = to_it87_gpio(chip);
mask = 1 << (gpio_num % 8);
group = (gpio_num / 8);
spin_lock(&it87_gpio->lock);
rc = superio_enter();
if (rc)
goto exit;
/* clear the output enable bit */
superio_clear_mask(mask, group + it87_gpio->output_base);
superio_exit();
exit:
spin_unlock(&it87_gpio->lock);
return rc;
}
static void it87_gpio_set(struct gpio_chip *chip,
unsigned gpio_num, int val)
{
u8 mask, curr_vals;
u16 reg;
struct it87_gpio *it87_gpio = to_it87_gpio(chip);
mask = 1 << (gpio_num % 8);
reg = (gpio_num / 8) + it87_gpio->io_base;
curr_vals = inb(reg);
if (val)
outb(curr_vals | mask, reg);
else
outb(curr_vals & ~mask, reg);
}
static int it87_gpio_direction_out(struct gpio_chip *chip,
unsigned gpio_num, int val)
{
u8 mask, group;
int rc = 0;
struct it87_gpio *it87_gpio = to_it87_gpio(chip);
mask = 1 << (gpio_num % 8);
group = (gpio_num / 8);
spin_lock(&it87_gpio->lock);
rc = superio_enter();
if (rc)
goto exit;
/* set the output enable bit */
superio_set_mask(mask, group + it87_gpio->output_base);
it87_gpio_set(chip, gpio_num, val);
superio_exit();
exit:
spin_unlock(&it87_gpio->lock);
return rc;
}
static struct gpio_chip it87_template_chip = {
.label = KBUILD_MODNAME,
.owner = THIS_MODULE,
.request = it87_gpio_request,
.get = it87_gpio_get,
.direction_input = it87_gpio_direction_in,
.set = it87_gpio_set,
.direction_output = it87_gpio_direction_out,
.base = -1
};
static int __init it87_gpio_init(void)
{
int rc = 0, i;
u16 chip_type;
u8 chip_rev, gpio_ba_reg;
char *labels, **labels_table;
struct it87_gpio *it87_gpio = &it87_gpio_chip;
rc = superio_enter();
if (rc)
return rc;
chip_type = superio_inw(CHIPID);
chip_rev = superio_inb(CHIPREV) & 0x0f;
superio_exit();
it87_gpio->chip = it87_template_chip;
switch (chip_type) {
case IT8728_ID:
case IT8732_ID:
gpio_ba_reg = 0x62;
it87_gpio->io_size = 8;
it87_gpio->output_base = 0xc8;
it87_gpio->simple_base = 0xc0;
it87_gpio->simple_size = 5;
it87_gpio->chip.ngpio = 64;
break;
case IT8761_ID:
gpio_ba_reg = 0x60;
it87_gpio->io_size = 4;
it87_gpio->output_base = 0xf0;
it87_gpio->simple_size = 0;
it87_gpio->chip.ngpio = 16;
break;
case NO_DEV_ID:
pr_err("no device\n");
return -ENODEV;
default:
pr_err("Unknown Chip found, Chip %04x Revision %x\n",
chip_type, chip_rev);
return -ENODEV;
}
rc = superio_enter();
if (rc)
return rc;
superio_select(GPIO);
/* fetch GPIO base address */
it87_gpio->io_base = superio_inw(gpio_ba_reg);
superio_exit();
pr_info("Found Chip IT%04x rev %x. %u GPIO lines starting at %04xh\n",
chip_type, chip_rev, it87_gpio->chip.ngpio,
it87_gpio->io_base);
if (!request_region(it87_gpio->io_base, it87_gpio->io_size,
KBUILD_MODNAME))
return -EBUSY;
/* Set up aliases for the GPIO connection.
*
* ITE documentation for recent chips such as the IT8728F
* refers to the GPIO lines as GPxy, with a coordinates system
* where x is the GPIO group (starting from 1) and y is the
* bit within the group.
*
* By creating these aliases, we make it easier to understand
* to which GPIO pin we're referring to.
*/
labels = kcalloc(it87_gpio->chip.ngpio, sizeof("it87_gpXY"),
GFP_KERNEL);
labels_table = kcalloc(it87_gpio->chip.ngpio, sizeof(const char *),
GFP_KERNEL);
if (!labels || !labels_table) {
rc = -ENOMEM;
goto labels_free;
}
for (i = 0; i < it87_gpio->chip.ngpio; i++) {
char *label = &labels[i * sizeof("it87_gpXY")];
sprintf(label, "it87_gp%u%u", 1+(i/8), i%8);
labels_table[i] = label;
}
it87_gpio->chip.names = (const char *const*)labels_table;
rc = gpiochip_add(&it87_gpio->chip);
if (rc)
goto labels_free;
return 0;
labels_free:
kfree(labels_table);
kfree(labels);
release_region(it87_gpio->io_base, it87_gpio->io_size);
return rc;
}
static void __exit it87_gpio_exit(void)
{
struct it87_gpio *it87_gpio = &it87_gpio_chip;
gpiochip_remove(&it87_gpio->chip);
release_region(it87_gpio->io_base, it87_gpio->io_size);
kfree(it87_gpio->chip.names[0]);
kfree(it87_gpio->chip.names);
}
module_init(it87_gpio_init);
module_exit(it87_gpio_exit);
MODULE_AUTHOR("Diego Elio Pettenò <flameeyes@flameeyes.eu>");
MODULE_DESCRIPTION("GPIO interface for IT87xx Super I/O chips");
MODULE_LICENSE("GPL");

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@ -1,230 +0,0 @@
/*
* 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");