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author | Jiri Kosina <jkosina@suse.cz> | 2013-01-29 10:48:30 +0100 |
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committer | Jiri Kosina <jkosina@suse.cz> | 2013-01-29 10:48:30 +0100 |
commit | 617677295b53a40d0e54aac4cbbc216ffbc755dd (patch) | |
tree | 51b9e87213243ed5efff252c8e8d8fec4eebc588 /drivers/gpio/gpiolib-acpi.c | |
parent | 5c8d1b68e01a144813e38795fe6dbe7ebb506131 (diff) | |
parent | 6abb7c25775b7fb2225ad0508236d63ca710e65f (diff) | |
download | linux-617677295b53a40d0e54aac4cbbc216ffbc755dd.tar.gz linux-617677295b53a40d0e54aac4cbbc216ffbc755dd.tar.bz2 linux-617677295b53a40d0e54aac4cbbc216ffbc755dd.zip |
Merge branch 'master' into for-next
Conflicts:
drivers/devfreq/exynos4_bus.c
Sync with Linus' tree to be able to apply patches that are
against newer code (mvneta).
Diffstat (limited to 'drivers/gpio/gpiolib-acpi.c')
-rw-r--r-- | drivers/gpio/gpiolib-acpi.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c new file mode 100644 index 000000000000..cbad6e908d30 --- /dev/null +++ b/drivers/gpio/gpiolib-acpi.c @@ -0,0 +1,54 @@ +/* + * ACPI helpers for GPIO API + * + * Copyright (C) 2012, Intel Corporation + * Authors: Mathias Nyman <mathias.nyman@linux.intel.com> + * Mika Westerberg <mika.westerberg@linux.intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/errno.h> +#include <linux/gpio.h> +#include <linux/export.h> +#include <linux/acpi_gpio.h> +#include <linux/acpi.h> + +static int acpi_gpiochip_find(struct gpio_chip *gc, void *data) +{ + if (!gc->dev) + return false; + + return ACPI_HANDLE(gc->dev) == data; +} + +/** + * acpi_get_gpio() - Translate ACPI GPIO pin to GPIO number usable with GPIO API + * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1") + * @pin: ACPI GPIO pin number (0-based, controller-relative) + * + * Returns GPIO number to use with Linux generic GPIO API, or errno error value + */ + +int acpi_get_gpio(char *path, int pin) +{ + struct gpio_chip *chip; + acpi_handle handle; + acpi_status status; + + status = acpi_get_handle(NULL, path, &handle); + if (ACPI_FAILURE(status)) + return -ENODEV; + + chip = gpiochip_find(handle, acpi_gpiochip_find); + if (!chip) + return -ENODEV; + + if (!gpio_is_valid(chip->base + pin)) + return -EINVAL; + + return chip->base + pin; +} +EXPORT_SYMBOL_GPL(acpi_get_gpio); |