238 lines
7.9 KiB
C
238 lines
7.9 KiB
C
#ifndef __LINUX_GPIO_DRIVER_H
|
|
#define __LINUX_GPIO_DRIVER_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/module.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/irqchip/chained_irq.h>
|
|
#include <linux/irqdomain.h>
|
|
|
|
struct device;
|
|
struct gpio_desc;
|
|
struct of_phandle_args;
|
|
struct device_node;
|
|
struct seq_file;
|
|
|
|
#ifdef CONFIG_GPIOLIB
|
|
|
|
/**
|
|
* struct gpio_chip - abstract a GPIO controller
|
|
* @label: for diagnostics
|
|
* @dev: optional device providing the GPIOs
|
|
* @owner: helps prevent removal of modules exporting active GPIOs
|
|
* @list: links gpio_chips together for traversal
|
|
* @request: optional hook for chip-specific activation, such as
|
|
* enabling module power and clock; may sleep
|
|
* @free: optional hook for chip-specific deactivation, such as
|
|
* disabling module power and clock; may sleep
|
|
* @get_direction: returns direction for signal "offset", 0=out, 1=in,
|
|
* (same as GPIOF_DIR_XXX), or negative error
|
|
* @direction_input: configures signal "offset" as input, or returns error
|
|
* @direction_output: configures signal "offset" as output, or returns error
|
|
* @get: returns value for signal "offset"; for output signals this
|
|
* returns either the value actually sensed, or zero
|
|
* @set: assigns output value for signal "offset"
|
|
* @set_debounce: optional hook for setting debounce time for specified gpio in
|
|
* interrupt triggered gpio chips
|
|
* @to_irq: optional hook supporting non-static gpio_to_irq() mappings;
|
|
* implementation may not sleep
|
|
* @dbg_show: optional routine to show contents in debugfs; default code
|
|
* will be used when this is omitted, but custom code can show extra
|
|
* state (such as pullup/pulldown configuration).
|
|
* @base: identifies the first GPIO number handled by this chip; or, if
|
|
* negative during registration, requests dynamic ID allocation.
|
|
* @ngpio: the number of GPIOs handled by this controller; the last GPIO
|
|
* handled is (base + ngpio - 1).
|
|
* @desc: array of ngpio descriptors. Private.
|
|
* @names: if set, must be an array of strings to use as alternative
|
|
* names for the GPIOs in this chip. Any entry in the array
|
|
* may be NULL if there is no alias for the GPIO, however the
|
|
* array must be @ngpio entries long. A name can include a single printk
|
|
* format specifier for an unsigned int. It is substituted by the actual
|
|
* number of the gpio.
|
|
* @can_sleep: flag must be set iff get()/set() methods sleep, as they
|
|
* must while accessing GPIO expander chips over I2C or SPI. This
|
|
* implies that if the chip supports IRQs, these IRQs need to be threaded
|
|
* as the chip access may sleep when e.g. reading out the IRQ status
|
|
* registers.
|
|
* @exported: flags if the gpiochip is exported for use from sysfs. Private.
|
|
*
|
|
* A gpio_chip can help platforms abstract various sources of GPIOs so
|
|
* they can all be accessed through a common programing interface.
|
|
* Example sources would be SOC controllers, FPGAs, multifunction
|
|
* chips, dedicated GPIO expanders, and so on.
|
|
*
|
|
* Each chip controls a number of signals, identified in method calls
|
|
* by "offset" values in the range 0..(@ngpio - 1). When those signals
|
|
* are referenced through calls like gpio_get_value(gpio), the offset
|
|
* is calculated by subtracting @base from the gpio number.
|
|
*/
|
|
struct gpio_chip {
|
|
const char *label;
|
|
struct device *dev;
|
|
struct module *owner;
|
|
struct list_head list;
|
|
|
|
int (*request)(struct gpio_chip *chip,
|
|
unsigned offset);
|
|
void (*free)(struct gpio_chip *chip,
|
|
unsigned offset);
|
|
int (*get_direction)(struct gpio_chip *chip,
|
|
unsigned offset);
|
|
int (*direction_input)(struct gpio_chip *chip,
|
|
unsigned offset);
|
|
int (*direction_output)(struct gpio_chip *chip,
|
|
unsigned offset, int value);
|
|
int (*get)(struct gpio_chip *chip,
|
|
unsigned offset);
|
|
void (*set)(struct gpio_chip *chip,
|
|
unsigned offset, int value);
|
|
int (*set_debounce)(struct gpio_chip *chip,
|
|
unsigned offset,
|
|
unsigned debounce);
|
|
|
|
int (*to_irq)(struct gpio_chip *chip,
|
|
unsigned offset);
|
|
|
|
void (*dbg_show)(struct seq_file *s,
|
|
struct gpio_chip *chip);
|
|
int base;
|
|
u16 ngpio;
|
|
struct gpio_desc *desc;
|
|
const char *const *names;
|
|
bool can_sleep;
|
|
bool exported;
|
|
|
|
#ifdef CONFIG_GPIOLIB_IRQCHIP
|
|
/*
|
|
* With CONFIG_GPIO_IRQCHIP we get an irqchip inside the gpiolib
|
|
* to handle IRQs for most practical cases.
|
|
*/
|
|
struct irq_chip *irqchip;
|
|
struct irq_domain *irqdomain;
|
|
unsigned int irq_base;
|
|
irq_flow_handler_t irq_handler;
|
|
unsigned int irq_default_type;
|
|
#endif
|
|
|
|
#if defined(CONFIG_OF_GPIO)
|
|
/*
|
|
* If CONFIG_OF is enabled, then all GPIO controllers described in the
|
|
* device tree automatically may have an OF translation
|
|
*/
|
|
struct device_node *of_node;
|
|
int of_gpio_n_cells;
|
|
int (*of_xlate)(struct gpio_chip *gc,
|
|
const struct of_phandle_args *gpiospec, u32 *flags);
|
|
#endif
|
|
#ifdef CONFIG_PINCTRL
|
|
/*
|
|
* If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
|
|
* describe the actual pin range which they serve in an SoC. This
|
|
* information would be used by pinctrl subsystem to configure
|
|
* corresponding pins for gpio usage.
|
|
*/
|
|
struct list_head pin_ranges;
|
|
#endif
|
|
};
|
|
|
|
extern const char *gpiochip_is_requested(struct gpio_chip *chip,
|
|
unsigned offset);
|
|
|
|
/* add/remove chips */
|
|
extern int gpiochip_add(struct gpio_chip *chip);
|
|
extern int __must_check gpiochip_remove(struct gpio_chip *chip);
|
|
extern struct gpio_chip *gpiochip_find(void *data,
|
|
int (*match)(struct gpio_chip *chip, void *data));
|
|
|
|
/* lock/unlock as IRQ */
|
|
int gpiod_lock_as_irq(struct gpio_desc *desc);
|
|
void gpiod_unlock_as_irq(struct gpio_desc *desc);
|
|
|
|
struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);
|
|
|
|
struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
|
|
u16 hwnum);
|
|
|
|
enum gpio_lookup_flags {
|
|
GPIO_ACTIVE_HIGH = (0 << 0),
|
|
GPIO_ACTIVE_LOW = (1 << 0),
|
|
GPIO_OPEN_DRAIN = (1 << 1),
|
|
GPIO_OPEN_SOURCE = (1 << 2),
|
|
};
|
|
|
|
/**
|
|
* struct gpiod_lookup - lookup table
|
|
* @chip_label: name of the chip the GPIO belongs to
|
|
* @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO
|
|
* @con_id: name of the GPIO from the device's point of view
|
|
* @idx: index of the GPIO in case several GPIOs share the same name
|
|
* @flags: mask of GPIO_* values
|
|
*
|
|
* gpiod_lookup is a lookup table for associating GPIOs to specific devices and
|
|
* functions using platform data.
|
|
*/
|
|
struct gpiod_lookup {
|
|
const char *chip_label;
|
|
u16 chip_hwnum;
|
|
const char *con_id;
|
|
unsigned int idx;
|
|
enum gpio_lookup_flags flags;
|
|
};
|
|
|
|
struct gpiod_lookup_table {
|
|
struct list_head list;
|
|
const char *dev_id;
|
|
struct gpiod_lookup table[];
|
|
};
|
|
|
|
/*
|
|
* Simple definition of a single GPIO under a con_id
|
|
*/
|
|
#define GPIO_LOOKUP(_chip_label, _chip_hwnum, _con_id, _flags) \
|
|
GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _con_id, 0, _flags)
|
|
|
|
/*
|
|
* Use this macro if you need to have several GPIOs under the same con_id.
|
|
* Each GPIO needs to use a different index and can be accessed using
|
|
* gpiod_get_index()
|
|
*/
|
|
#define GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _con_id, _idx, _flags) \
|
|
{ \
|
|
.chip_label = _chip_label, \
|
|
.chip_hwnum = _chip_hwnum, \
|
|
.con_id = _con_id, \
|
|
.idx = _idx, \
|
|
.flags = _flags, \
|
|
}
|
|
|
|
void gpiod_add_lookup_table(struct gpiod_lookup_table *table);
|
|
|
|
#ifdef CONFIG_GPIOLIB_IRQCHIP
|
|
|
|
void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
|
|
struct irq_chip *irqchip,
|
|
int parent_irq,
|
|
irq_flow_handler_t parent_handler);
|
|
|
|
int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
|
|
struct irq_chip *irqchip,
|
|
unsigned int first_irq,
|
|
irq_flow_handler_t handler,
|
|
unsigned int type);
|
|
|
|
#endif /* CONFIG_GPIO_IRQCHIP */
|
|
|
|
#else /* CONFIG_GPIOLIB */
|
|
|
|
static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
|
|
{
|
|
/* GPIO can never have been requested */
|
|
WARN_ON(1);
|
|
return ERR_PTR(-ENODEV);
|
|
}
|
|
|
|
#endif /* CONFIG_GPIOLIB */
|
|
|
|
#endif
|