diff options
author | Simon Guinot <simon.guinot@sequanux.org> | 2013-08-29 22:56:56 +0200 |
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committer | Linus Walleij <linus.walleij@linaro.org> | 2013-08-30 09:25:52 +0200 |
commit | 6c17aa0138a6c55364936bbaa35846e09a4db53b (patch) | |
tree | ddbe02fbee48e5cc0f058e9cda30a1c659e1df59 /drivers/gpio/gpio-f7188x.c | |
parent | c6641da12e0f5516b75386dccedf163bbfeaabe0 (diff) | |
download | linux-6c17aa0138a6c55364936bbaa35846e09a4db53b.tar.bz2 |
gpio: add GPIO support for F71882FG and F71889F
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.
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...
Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpio-f7188x.c')
-rw-r--r-- | drivers/gpio/gpio-f7188x.c | 469 |
1 files changed, 469 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio-f7188x.c new file mode 100644 index 000000000000..9cb8320e1181 --- /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@sequanux.org> + * + * 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@sequanux.org>"); +MODULE_LICENSE("GPL"); |