diff options
Diffstat (limited to 'drivers/gpio/sch_gpio.c')
| -rw-r--r-- | drivers/gpio/sch_gpio.c | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/drivers/gpio/sch_gpio.c b/drivers/gpio/sch_gpio.c new file mode 100644 index 00000000000..761071ae359 --- /dev/null +++ b/drivers/gpio/sch_gpio.c @@ -0,0 +1,282 @@ +/* + * sch_gpio.c - GPIO interface for Intel Poulsbo SCH + * + * Copyright (c) 2010 CompuLab Ltd + * 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/acpi.h> +#include <linux/platform_device.h> + +#include <linux/gpio.h> + +static DEFINE_SPINLOCK(gpio_lock); + +#define CGEN (0x00) +#define CGIO (0x04) +#define CGLV (0x08) + +#define RGEN (0x20) +#define RGIO (0x24) +#define RGLV (0x28) + +static unsigned short gpio_ba; + +static int sch_gpio_core_direction_in(struct gpio_chip *gc, unsigned gpio_num) +{ + u8 curr_dirs; + unsigned short offset, bit; + + spin_lock(&gpio_lock); + + offset = CGIO + gpio_num / 8; + bit = gpio_num % 8; + + curr_dirs = inb(gpio_ba + offset); + + if (!(curr_dirs & (1 << bit))) + outb(curr_dirs | (1 << bit), gpio_ba + offset); + + spin_unlock(&gpio_lock); + return 0; +} + +static int sch_gpio_core_get(struct gpio_chip *gc, unsigned gpio_num) +{ + int res; + unsigned short offset, bit; + + offset = CGLV + gpio_num / 8; + bit = gpio_num % 8; + + res = !!(inb(gpio_ba + offset) & (1 << bit)); + return res; +} + +static void sch_gpio_core_set(struct gpio_chip *gc, unsigned gpio_num, int val) +{ + u8 curr_vals; + unsigned short offset, bit; + + spin_lock(&gpio_lock); + + offset = CGLV + gpio_num / 8; + bit = gpio_num % 8; + + curr_vals = inb(gpio_ba + offset); + + if (val) + outb(curr_vals | (1 << bit), gpio_ba + offset); + else + outb((curr_vals & ~(1 << bit)), gpio_ba + offset); + spin_unlock(&gpio_lock); +} + +static int sch_gpio_core_direction_out(struct gpio_chip *gc, + unsigned gpio_num, int val) +{ + u8 curr_dirs; + unsigned short offset, bit; + + sch_gpio_core_set(gc, gpio_num, val); + + spin_lock(&gpio_lock); + + offset = CGIO + gpio_num / 8; + bit = gpio_num % 8; + + curr_dirs = inb(gpio_ba + offset); + if (curr_dirs & (1 << bit)) + outb(curr_dirs & ~(1 << bit), gpio_ba + offset); + + spin_unlock(&gpio_lock); + return 0; +} + +static struct gpio_chip sch_gpio_core = { + .label = "sch_gpio_core", + .owner = THIS_MODULE, + .direction_input = sch_gpio_core_direction_in, + .get = sch_gpio_core_get, + .direction_output = sch_gpio_core_direction_out, + .set = sch_gpio_core_set, +}; + +static int sch_gpio_resume_direction_in(struct gpio_chip *gc, + unsigned gpio_num) +{ + u8 curr_dirs; + + spin_lock(&gpio_lock); + + curr_dirs = inb(gpio_ba + RGIO); + + if (!(curr_dirs & (1 << gpio_num))) + outb(curr_dirs | (1 << gpio_num) , gpio_ba + RGIO); + + spin_unlock(&gpio_lock); + return 0; +} + +static int sch_gpio_resume_get(struct gpio_chip *gc, unsigned gpio_num) +{ + return !!(inb(gpio_ba + RGLV) & (1 << gpio_num)); +} + +static void sch_gpio_resume_set(struct gpio_chip *gc, + unsigned gpio_num, int val) +{ + u8 curr_vals; + + spin_lock(&gpio_lock); + + curr_vals = inb(gpio_ba + RGLV); + + if (val) + outb(curr_vals | (1 << gpio_num), gpio_ba + RGLV); + else + outb((curr_vals & ~(1 << gpio_num)), gpio_ba + RGLV); + + spin_unlock(&gpio_lock); +} + +static int sch_gpio_resume_direction_out(struct gpio_chip *gc, + unsigned gpio_num, int val) +{ + u8 curr_dirs; + + sch_gpio_resume_set(gc, gpio_num, val); + + spin_lock(&gpio_lock); + + curr_dirs = inb(gpio_ba + RGIO); + if (curr_dirs & (1 << gpio_num)) + outb(curr_dirs & ~(1 << gpio_num), gpio_ba + RGIO); + + spin_unlock(&gpio_lock); + return 0; +} + +static struct gpio_chip sch_gpio_resume = { + .label = "sch_gpio_resume", + .owner = THIS_MODULE, + .direction_input = sch_gpio_resume_direction_in, + .get = sch_gpio_resume_get, + .direction_output = sch_gpio_resume_direction_out, + .set = sch_gpio_resume_set, +}; + +static int __devinit sch_gpio_probe(struct platform_device *pdev) +{ + struct resource *res; + int err; + + res = platform_get_resource(pdev, IORESOURCE_IO, 0); + if (!res) + return -EBUSY; + + if (!request_region(res->start, resource_size(res), pdev->name)) + return -EBUSY; + + gpio_ba = res->start; + + sch_gpio_core.base = 0; + sch_gpio_core.ngpio = 10; + sch_gpio_core.dev = &pdev->dev; + + sch_gpio_resume.base = 10; + sch_gpio_resume.ngpio = 4; + sch_gpio_resume.dev = &pdev->dev; + + err = gpiochip_add(&sch_gpio_core); + if (err < 0) + goto err_sch_gpio_core; + + err = gpiochip_add(&sch_gpio_resume); + if (err < 0) + goto err_sch_gpio_resume; + + /* + * GPIO[6:0] enabled by default + * GPIO7 is configured by the CMC as SLPIOVR + * Enable GPIO[9:8] core powered gpios explicitly + */ + outb(0x3, gpio_ba + CGEN + 1); + /* + * SUS_GPIO[2:0] enabled by default + * Enable SUS_GPIO3 resume powered gpio explicitly + */ + outb(0x8, gpio_ba + RGEN); + + return 0; + +err_sch_gpio_resume: + gpiochip_remove(&sch_gpio_core); + +err_sch_gpio_core: + release_region(res->start, resource_size(res)); + gpio_ba = 0; + + return err; +} + +static int __devexit sch_gpio_remove(struct platform_device *pdev) +{ + struct resource *res; + if (gpio_ba) { + gpiochip_remove(&sch_gpio_core); + gpiochip_remove(&sch_gpio_resume); + + res = platform_get_resource(pdev, IORESOURCE_IO, 0); + + release_region(res->start, resource_size(res)); + gpio_ba = 0; + } + + return 0; +} + +static struct platform_driver sch_gpio_driver = { + .driver = { + .name = "sch_gpio", + .owner = THIS_MODULE, + }, + .probe = sch_gpio_probe, + .remove = __devexit_p(sch_gpio_remove), +}; + +static int __init sch_gpio_init(void) +{ + return platform_driver_register(&sch_gpio_driver); +} + +static void __exit sch_gpio_exit(void) +{ + platform_driver_unregister(&sch_gpio_driver); +} + +module_init(sch_gpio_init); +module_exit(sch_gpio_exit); + +MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>"); +MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:sch_gpio"); |