linux/include/asm-generic/gpio.h
Mika Westerberg 7ca267faba gpio: Increase ARCH_NR_GPIOs to 512
Some newer Intel SoCs, like Braswell already have more than 256 GPIOs
available so the default limit is exceeded. Instead of adding more
architecture specific gpio.h files with custom ARCH_NR_GPIOs we increase
the gpiolib default limit to be twice the current.

Current generic ARCH_NR_GPIOS limit is 256 which starts to be too small
for newer Intel SoCs like Braswell. In order to support GPIO controllers
on these SoCs we increase ARCH_NR_GPIOS to be 512 which should be
sufficient for now.

The kernel size increases a bit with this change. Below is an example of
x86_64 kernel image.

ARCH_NR_GPIOS=256
 text     data    bss     dec      hex    filename
 11476173 1971328 1265664 14713165 e0814d vmlinux

ARCH_NR_GPIOS=512
 text     data    bss     dec      hex    filename
 11476173 1971328 1269760 14717261 e0914d vmlinux

So the BSS size and this the kernel image size increases by 4k.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-23 17:51:39 +02:00

221 lines
5.7 KiB
C

#ifndef _ASM_GENERIC_GPIO_H
#define _ASM_GENERIC_GPIO_H
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/of.h>
#include <linux/pinctrl/pinctrl.h>
#ifdef CONFIG_GPIOLIB
#include <linux/compiler.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/consumer.h>
/* Platforms may implement their GPIO interface with library code,
* at a small performance cost for non-inlined operations and some
* extra memory (for code and for per-GPIO table entries).
*
* While the GPIO programming interface defines valid GPIO numbers
* to be in the range 0..MAX_INT, this library restricts them to the
* smaller range 0..ARCH_NR_GPIOS-1.
*
* ARCH_NR_GPIOS is somewhat arbitrary; it usually reflects the sum of
* builtin/SoC GPIOs plus a number of GPIOs on expanders; the latter is
* actually an estimate of a board-specific value.
*/
#ifndef ARCH_NR_GPIOS
#define ARCH_NR_GPIOS 512
#endif
/*
* "valid" GPIO numbers are nonnegative and may be passed to
* setup routines like gpio_request(). only some valid numbers
* can successfully be requested and used.
*
* Invalid GPIO numbers are useful for indicating no-such-GPIO in
* platform data and other tables.
*/
static inline bool gpio_is_valid(int number)
{
return number >= 0 && number < ARCH_NR_GPIOS;
}
struct device;
struct gpio;
struct seq_file;
struct module;
struct device_node;
struct gpio_desc;
/* caller holds gpio_lock *OR* gpio is marked as requested */
static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
{
return gpiod_to_chip(gpio_to_desc(gpio));
}
/* Always use the library code for GPIO management calls,
* or when sleeping may be involved.
*/
extern int gpio_request(unsigned gpio, const char *label);
extern void gpio_free(unsigned gpio);
static inline int gpio_direction_input(unsigned gpio)
{
return gpiod_direction_input(gpio_to_desc(gpio));
}
static inline int gpio_direction_output(unsigned gpio, int value)
{
return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
}
static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
{
return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
}
static inline int gpio_get_value_cansleep(unsigned gpio)
{
return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
}
static inline void gpio_set_value_cansleep(unsigned gpio, int value)
{
return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
}
/* A platform's <asm/gpio.h> code may want to inline the I/O calls when
* the GPIO is constant and refers to some always-present controller,
* giving direct access to chip registers and tight bitbanging loops.
*/
static inline int __gpio_get_value(unsigned gpio)
{
return gpiod_get_raw_value(gpio_to_desc(gpio));
}
static inline void __gpio_set_value(unsigned gpio, int value)
{
return gpiod_set_raw_value(gpio_to_desc(gpio), value);
}
static inline int __gpio_cansleep(unsigned gpio)
{
return gpiod_cansleep(gpio_to_desc(gpio));
}
static inline int __gpio_to_irq(unsigned gpio)
{
return gpiod_to_irq(gpio_to_desc(gpio));
}
extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
extern int gpio_request_array(const struct gpio *array, size_t num);
extern void gpio_free_array(const struct gpio *array, size_t num);
/*
* A sysfs interface can be exported by individual drivers if they want,
* but more typically is configured entirely from userspace.
*/
static inline int gpio_export(unsigned gpio, bool direction_may_change)
{
return gpiod_export(gpio_to_desc(gpio), direction_may_change);
}
static inline int gpio_export_link(struct device *dev, const char *name,
unsigned gpio)
{
return gpiod_export_link(dev, name, gpio_to_desc(gpio));
}
static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
{
return gpiod_sysfs_set_active_low(gpio_to_desc(gpio), value);
}
static inline void gpio_unexport(unsigned gpio)
{
gpiod_unexport(gpio_to_desc(gpio));
}
#ifdef CONFIG_PINCTRL
/**
* struct gpio_pin_range - pin range controlled by a gpio chip
* @head: list for maintaining set of pin ranges, used internally
* @pctldev: pinctrl device which handles corresponding pins
* @range: actual range of pins controlled by a gpio controller
*/
struct gpio_pin_range {
struct list_head node;
struct pinctrl_dev *pctldev;
struct pinctrl_gpio_range range;
};
int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
unsigned int gpio_offset, unsigned int pin_offset,
unsigned int npins);
int gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group);
void gpiochip_remove_pin_ranges(struct gpio_chip *chip);
#else
static inline int
gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
unsigned int gpio_offset, unsigned int pin_offset,
unsigned int npins)
{
return 0;
}
static inline int
gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group)
{
return 0;
}
static inline void
gpiochip_remove_pin_ranges(struct gpio_chip *chip)
{
}
#endif /* CONFIG_PINCTRL */
#else /* !CONFIG_GPIOLIB */
static inline bool gpio_is_valid(int number)
{
/* only non-negative numbers are valid */
return number >= 0;
}
/* platforms that don't directly support access to GPIOs through I2C, SPI,
* or other blocking infrastructure can use these wrappers.
*/
static inline int gpio_cansleep(unsigned gpio)
{
return 0;
}
static inline int gpio_get_value_cansleep(unsigned gpio)
{
might_sleep();
return __gpio_get_value(gpio);
}
static inline void gpio_set_value_cansleep(unsigned gpio, int value)
{
might_sleep();
__gpio_set_value(gpio, value);
}
#endif /* !CONFIG_GPIOLIB */
#endif /* _ASM_GENERIC_GPIO_H */