Commit b8664924 authored by Diego Elio Pettenò's avatar Diego Elio Pettenò Committed by Linus Walleij
Browse files

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: default avatarDiego Elio Pettenò <flameeyes@flameeyes.eu>
Signed-off-by: default avatarChristophe Vu-Brugier <cvubrugier@fastmail.fm>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 48b5953e

drivers/gpio/Kconfig

+10 −4
Original line number Diff line number Diff line
@@ -235,11 +235,17 @@ config GPIO_IOP 


	  If unsure, say N.



config GPIO_IT8761E

	tristate "IT8761E GPIO support"

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"

drivers/gpio/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -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

drivers/gpio/gpio-it87.c

0 → 100644
+411 −0
Original line number Diff line number Diff line 
/*

 *  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");

drivers/gpio/gpio-it8761e.c

deleted100644 → 0
+0 −230
Original line number Diff line number Diff line 
/*

 *  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");

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