[PATCH v4] gpio: add GPIO support for F71882FG and F71889F

From: Simon Guinot
Date: Thu Aug 29 2013 - 16:55:58 EST


This patch adds support for the GPIOs found on the Fintek super-I/O
chips F71882FG and F71889F.

A super-I/O is a legacy I/O controller embedded on x86 motherboards. It
is used to connect the low-bandwidth devices. Among others functions the
F71882FG/F71889F provides: a parallel port, two serial ports, a keyboard
controller, an hardware monitoring controller and some GPIO pins.

Note that this super-I/Os are embedded on some Atom-based LaCie NASes.
The GPIOs are used to control the LEDs and the hard drive power.

Signed-off-by: Simon Guinot <simon.guinot@xxxxxxxxxxxx>
---
Linus,

Here is a v4 for the driver gpio-f7188x. It fixes an issue noticed by
Guenter: the driver needs to use request_muxed_region in order to
synchronize with the hwmon and watchdog drivers for the same chip.

I should have sent this update earlier but I was waiting for more
changes (ACPI support)... All my apologies for the inconvenience.

Please drop the v3 and apply this one.

Thanks,

Simon

Changes since v3:
- Use request_muxed_region to protect the I/O ports against concurrent
accesses.

Changes since v2:
- Remove useless NULL setters for driver data.

Changes since v1:
- Enhance the commit message by describing what is a Super-I/O.
- Use self-explanatory names for the GPIO register macros.
- Add a comment to explain the platform device and driver registration.
- Fix gpio_get when GPIO is configured in input mode. I only had
the hardware to check this mode recently...

drivers/gpio/Kconfig | 10 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-f7188x.c | 469 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 480 insertions(+)
create mode 100644 drivers/gpio/gpio-f7188x.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b2450ba..c5ae0ac 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -146,6 +146,16 @@ config GPIO_MM_LANTIQ
(EBU) found on Lantiq SoCs. The gpios are output only as they are
created by attaching a 16bit latch to the bus.

+config GPIO_F7188X
+ tristate "F71882FG and F71889F GPIO support"
+ depends on X86
+ help
+ This option enables support for GPIOs found on Fintek Super-I/O
+ chips F71882FG and F71889F.
+
+ To compile this driver as a module, choose M here: the module will
+ be called f7188x-gpio.
+
config GPIO_MPC5200
def_bool y
depends on PPC_MPC52xx
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index ef3e983..bc7a677 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_GPIO_DA9055) += gpio-da9055.o
obj-$(CONFIG_ARCH_DAVINCI) += gpio-davinci.o
obj-$(CONFIG_GPIO_EM) += gpio-em.o
obj-$(CONFIG_GPIO_EP93XX) += gpio-ep93xx.o
+obj-$(CONFIG_GPIO_F7188X) += gpio-f7188x.o
obj-$(CONFIG_GPIO_GE_FPGA) += gpio-ge.o
obj-$(CONFIG_GPIO_GRGPIO) += gpio-grgpio.o
obj-$(CONFIG_GPIO_ICH) += gpio-ich.o
diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio-f7188x.c
new file mode 100644
index 0000000..9cb8320
--- /dev/null
+++ b/drivers/gpio/gpio-f7188x.c
@@ -0,0 +1,469 @@
+/*
+ * GPIO driver for Fintek Super-I/O F71882 and F71889
+ *
+ * Copyright (C) 2010-2013 LaCie
+ *
+ * Author: Simon Guinot <simon.guinot@xxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+
+#define DRVNAME "gpio-f7188x"
+
+/*
+ * Super-I/O registers
+ */
+#define SIO_LDSEL 0x07 /* Logical device select */
+#define SIO_DEVID 0x20 /* Device ID (2 bytes) */
+#define SIO_DEVREV 0x22 /* Device revision */
+#define SIO_MANID 0x23 /* Fintek ID (2 bytes) */
+
+#define SIO_LD_GPIO 0x06 /* GPIO logical device */
+#define SIO_UNLOCK_KEY 0x87 /* Key to enable Super-I/O */
+#define SIO_LOCK_KEY 0xAA /* Key to disable Super-I/O */
+
+#define SIO_FINTEK_ID 0x1934 /* Manufacturer ID */
+#define SIO_F71882_ID 0x0541 /* F71882 chipset ID */
+#define SIO_F71889_ID 0x0909 /* F71889 chipset ID */
+
+enum chips { f71882fg, f71889f };
+
+static const char * const f7188x_names[] = {
+ "f71882fg",
+ "f71889f",
+};
+
+struct f7188x_sio {
+ int addr;
+ enum chips type;
+};
+
+struct f7188x_gpio_bank {
+ struct gpio_chip chip;
+ unsigned int regbase;
+ struct f7188x_gpio_data *data;
+};
+
+struct f7188x_gpio_data {
+ struct f7188x_sio *sio;
+ int nr_bank;
+ struct f7188x_gpio_bank *bank;
+};
+
+/*
+ * Super-I/O functions.
+ */
+
+static inline int superio_inb(int base, int reg)
+{
+ outb(reg, base);
+ return inb(base + 1);
+}
+
+static int superio_inw(int base, int reg)
+{
+ int val;
+
+ outb(reg++, base);
+ val = inb(base + 1) << 8;
+ outb(reg, base);
+ val |= inb(base + 1);
+
+ return val;
+}
+
+static inline void superio_outb(int base, int reg, int val)
+{
+ outb(reg, base);
+ outb(val, base + 1);
+}
+
+static inline int superio_enter(int base)
+{
+ /* Don't step on other drivers' I/O space by accident. */
+ if (!request_muxed_region(base, 2, DRVNAME)) {
+ pr_err(DRVNAME "I/O address 0x%04x already in use\n", base);
+ return -EBUSY;
+ }
+
+ /* According to the datasheet the key must be send twice. */
+ outb(SIO_UNLOCK_KEY, base);
+ outb(SIO_UNLOCK_KEY, base);
+
+ return 0;
+}
+
+static inline void superio_select(int base, int ld)
+{
+ outb(SIO_LDSEL, base);
+ outb(ld, base + 1);
+}
+
+static inline void superio_exit(int base)
+{
+ outb(SIO_LOCK_KEY, base);
+ release_region(base, 2);
+}
+
+/*
+ * GPIO chip.
+ */
+
+static int f7188x_gpio_direction_in(struct gpio_chip *chip, unsigned offset);
+static int f7188x_gpio_get(struct gpio_chip *chip, unsigned offset);
+static int f7188x_gpio_direction_out(struct gpio_chip *chip,
+ unsigned offset, int value);
+static void f7188x_gpio_set(struct gpio_chip *chip, unsigned offset, int value);
+
+#define F7188X_GPIO_BANK(_base, _ngpio, _regbase) \
+ { \
+ .chip = { \
+ .label = DRVNAME, \
+ .owner = THIS_MODULE, \
+ .direction_input = f7188x_gpio_direction_in, \
+ .get = f7188x_gpio_get, \
+ .direction_output = f7188x_gpio_direction_out, \
+ .set = f7188x_gpio_set, \
+ .base = _base, \
+ .ngpio = _ngpio, \
+ }, \
+ .regbase = _regbase, \
+ }
+
+#define gpio_dir(base) (base + 0)
+#define gpio_data_out(base) (base + 1)
+#define gpio_data_in(base) (base + 2)
+/* Output mode register (0:open drain 1:push-pull). */
+#define gpio_out_mode(base) (base + 3)
+
+static struct f7188x_gpio_bank f71882_gpio_bank[] = {
+ F7188X_GPIO_BANK(0 , 8, 0xF0),
+ F7188X_GPIO_BANK(10, 8, 0xE0),
+ F7188X_GPIO_BANK(20, 8, 0xD0),
+ F7188X_GPIO_BANK(30, 4, 0xC0),
+ F7188X_GPIO_BANK(40, 4, 0xB0),
+};
+
+static struct f7188x_gpio_bank f71889_gpio_bank[] = {
+ F7188X_GPIO_BANK(0 , 7, 0xF0),
+ F7188X_GPIO_BANK(10, 7, 0xE0),
+ F7188X_GPIO_BANK(20, 8, 0xD0),
+ F7188X_GPIO_BANK(30, 8, 0xC0),
+ F7188X_GPIO_BANK(40, 8, 0xB0),
+ F7188X_GPIO_BANK(50, 5, 0xA0),
+ F7188X_GPIO_BANK(60, 8, 0x90),
+ F7188X_GPIO_BANK(70, 8, 0x80),
+};
+
+static int f7188x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
+{
+ int err;
+ struct f7188x_gpio_bank *bank =
+ container_of(chip, struct f7188x_gpio_bank, chip);
+ struct f7188x_sio *sio = bank->data->sio;
+ u8 dir;
+
+ err = superio_enter(sio->addr);
+ if (err)
+ return err;
+ superio_select(sio->addr, SIO_LD_GPIO);
+
+ dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
+ dir &= ~(1 << offset);
+ superio_outb(sio->addr, gpio_dir(bank->regbase), dir);
+
+ superio_exit(sio->addr);
+
+ return 0;
+}
+
+static int f7188x_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ int err;
+ struct f7188x_gpio_bank *bank =
+ container_of(chip, struct f7188x_gpio_bank, chip);
+ struct f7188x_sio *sio = bank->data->sio;
+ u8 dir, data;
+
+ err = superio_enter(sio->addr);
+ if (err)
+ return err;
+ superio_select(sio->addr, SIO_LD_GPIO);
+
+ dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
+ dir = !!(dir & (1 << offset));
+ if (dir)
+ data = superio_inb(sio->addr, gpio_data_out(bank->regbase));
+ else
+ data = superio_inb(sio->addr, gpio_data_in(bank->regbase));
+
+ superio_exit(sio->addr);
+
+ return !!(data & 1 << offset);
+}
+
+static int f7188x_gpio_direction_out(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ int err;
+ struct f7188x_gpio_bank *bank =
+ container_of(chip, struct f7188x_gpio_bank, chip);
+ struct f7188x_sio *sio = bank->data->sio;
+ u8 dir, data_out;
+
+ err = superio_enter(sio->addr);
+ if (err)
+ return err;
+ superio_select(sio->addr, SIO_LD_GPIO);
+
+ data_out = superio_inb(sio->addr, gpio_data_out(bank->regbase));
+ if (value)
+ data_out |= (1 << offset);
+ else
+ data_out &= ~(1 << offset);
+ superio_outb(sio->addr, gpio_data_out(bank->regbase), data_out);
+
+ dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
+ dir |= (1 << offset);
+ superio_outb(sio->addr, gpio_dir(bank->regbase), dir);
+
+ superio_exit(sio->addr);
+
+ return 0;
+}
+
+static void f7188x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ int err;
+ struct f7188x_gpio_bank *bank =
+ container_of(chip, struct f7188x_gpio_bank, chip);
+ struct f7188x_sio *sio = bank->data->sio;
+ u8 data_out;
+
+ err = superio_enter(sio->addr);
+ if (err)
+ return;
+ superio_select(sio->addr, SIO_LD_GPIO);
+
+ data_out = superio_inb(sio->addr, gpio_data_out(bank->regbase));
+ if (value)
+ data_out |= (1 << offset);
+ else
+ data_out &= ~(1 << offset);
+ superio_outb(sio->addr, gpio_data_out(bank->regbase), data_out);
+
+ superio_exit(sio->addr);
+}
+
+/*
+ * Platform device and driver.
+ */
+
+static int f7188x_gpio_probe(struct platform_device *pdev)
+{
+ int err;
+ int i;
+ struct f7188x_sio *sio = pdev->dev.platform_data;
+ struct f7188x_gpio_data *data;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ switch (sio->type) {
+ case f71882fg:
+ data->nr_bank = ARRAY_SIZE(f71882_gpio_bank);
+ data->bank = f71882_gpio_bank;
+ break;
+ case f71889f:
+ data->nr_bank = ARRAY_SIZE(f71889_gpio_bank);
+ data->bank = f71889_gpio_bank;
+ break;
+ default:
+ return -ENODEV;
+ }
+ data->sio = sio;
+
+ platform_set_drvdata(pdev, data);
+
+ /* For each GPIO bank, register a GPIO chip. */
+ for (i = 0; i < data->nr_bank; i++) {
+ struct f7188x_gpio_bank *bank = &data->bank[i];
+
+ bank->chip.dev = &pdev->dev;
+ bank->data = data;
+
+ err = gpiochip_add(&bank->chip);
+ if (err) {
+ dev_err(&pdev->dev,
+ "Failed to register gpiochip %d: %d\n",
+ i, err);
+ goto err_gpiochip;
+ }
+ }
+
+ return 0;
+
+err_gpiochip:
+ for (i = i - 1; i >= 0; i--) {
+ struct f7188x_gpio_bank *bank = &data->bank[i];
+ int tmp;
+
+ tmp = gpiochip_remove(&bank->chip);
+ if (tmp < 0)
+ dev_err(&pdev->dev,
+ "Failed to remove gpiochip %d: %d\n",
+ i, tmp);
+ }
+
+ return err;
+}
+
+static int f7188x_gpio_remove(struct platform_device *pdev)
+{
+ int err;
+ int i;
+ struct f7188x_gpio_data *data = platform_get_drvdata(pdev);
+
+ for (i = 0; i < data->nr_bank; i++) {
+ struct f7188x_gpio_bank *bank = &data->bank[i];
+
+ err = gpiochip_remove(&bank->chip);
+ if (err) {
+ dev_err(&pdev->dev,
+ "Failed to remove GPIO gpiochip %d: %d\n",
+ i, err);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int __init f7188x_find(int addr, struct f7188x_sio *sio)
+{
+ int err;
+ u16 devid;
+
+ err = superio_enter(addr);
+ if (err)
+ return err;
+
+ err = -ENODEV;
+ devid = superio_inw(addr, SIO_MANID);
+ if (devid != SIO_FINTEK_ID) {
+ pr_debug(DRVNAME ": Not a Fintek device at 0x%08x\n", addr);
+ goto err;
+ }
+
+ devid = superio_inw(addr, SIO_DEVID);
+ switch (devid) {
+ case SIO_F71882_ID:
+ sio->type = f71882fg;
+ break;
+ case SIO_F71889_ID:
+ sio->type = f71889f;
+ break;
+ default:
+ pr_info(DRVNAME ": Unsupported Fintek device 0x%04x\n", devid);
+ goto err;
+ }
+ sio->addr = addr;
+ err = 0;
+
+ pr_info(DRVNAME ": Found %s at %#x, revision %d\n",
+ f7188x_names[sio->type],
+ (unsigned int) addr,
+ (int) superio_inb(addr, SIO_DEVREV));
+
+err:
+ superio_exit(addr);
+ return err;
+}
+
+static struct platform_device *f7188x_gpio_pdev;
+
+static int __init
+f7188x_gpio_device_add(const struct f7188x_sio *sio)
+{
+ int err;
+
+ f7188x_gpio_pdev = platform_device_alloc(DRVNAME, -1);
+ if (!f7188x_gpio_pdev)
+ return -ENOMEM;
+
+ err = platform_device_add_data(f7188x_gpio_pdev,
+ sio, sizeof(*sio));
+ if (err) {
+ pr_err(DRVNAME "Platform data allocation failed\n");
+ goto err;
+ }
+
+ err = platform_device_add(f7188x_gpio_pdev);
+ if (err) {
+ pr_err(DRVNAME "Device addition failed\n");
+ goto err;
+ }
+
+ return 0;
+
+err:
+ platform_device_put(f7188x_gpio_pdev);
+
+ return err;
+}
+
+/*
+ * Try to match a supported Fintech device by reading the (hard-wired)
+ * configuration I/O ports. If available, then register both the platform
+ * device and driver to support the GPIOs.
+ */
+
+static struct platform_driver f7188x_gpio_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = DRVNAME,
+ },
+ .probe = f7188x_gpio_probe,
+ .remove = f7188x_gpio_remove,
+};
+
+static int __init f7188x_gpio_init(void)
+{
+ int err;
+ struct f7188x_sio sio;
+
+ if (f7188x_find(0x2e, &sio) &&
+ f7188x_find(0x4e, &sio))
+ return -ENODEV;
+
+ err = platform_driver_register(&f7188x_gpio_driver);
+ if (!err) {
+ err = f7188x_gpio_device_add(&sio);
+ if (err)
+ platform_driver_unregister(&f7188x_gpio_driver);
+ }
+
+ return err;
+}
+subsys_initcall(f7188x_gpio_init);
+
+static void __exit f7188x_gpio_exit(void)
+{
+ platform_device_unregister(f7188x_gpio_pdev);
+ platform_driver_unregister(&f7188x_gpio_driver);
+}
+module_exit(f7188x_gpio_exit);
+
+MODULE_DESCRIPTION("GPIO driver for Super-I/O chips F71882FG and F71889F");
+MODULE_AUTHOR("Simon Guinot <simon.guinot@xxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
--
1.7.10.4

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