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authorDiego Elio Pettenò <flameeyes@flameeyes.eu>2015-09-21 19:24:24 +0300
committerLinus Walleij <linus.walleij@linaro.org>2015-10-02 14:19:35 +0300
commitb8664924e8071b67b99f05b13e669e20104d7709 (patch)
treeacbe80f4ddc945102dadd077ef4db00f6f3925bb /drivers/gpio
parent48b5953ed826224a1332f2fd784d37d5f084ca9c (diff)
downloadlinux-b8664924e8071b67b99f05b13e669e20104d7709.tar.xz
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>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/Kconfig14
-rw-r--r--drivers/gpio/Makefile2
-rw-r--r--drivers/gpio/gpio-it87.c411
-rw-r--r--drivers/gpio/gpio-it8761e.c230
4 files changed, 422 insertions, 235 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 2026034879cb..63000b1f9da8 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -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"
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 0d30b645965b..77a07e9d014a 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -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
diff --git a/drivers/gpio/gpio-it87.c b/drivers/gpio/gpio-it87.c
new file mode 100644
index 000000000000..21f6f7c0eb34
--- /dev/null
+++ b/drivers/gpio/gpio-it87.c
@@ -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");
diff --git a/drivers/gpio/gpio-it8761e.c b/drivers/gpio/gpio-it8761e.c
deleted file mode 100644
index 30a8f24c92c5..000000000000
--- a/drivers/gpio/gpio-it8761e.c
+++ /dev/null
@@ -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");