[linux-2.6-block.git] / include / linux / gpio / driver.h

#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 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 gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset);
void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset);

struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);

#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 */

int gpiochip_request_own_desc(struct gpio_desc *desc, const char *label);
void gpiochip_free_own_desc(struct gpio_desc *desc);

#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
Commit	Line	Data
79a9becd AC	1	#ifndef __LINUX_GPIO_DRIVER_H
	2	#define __LINUX_GPIO_DRIVER_H
	3
	4	#include <linux/types.h>
c9a9972b	5	#include <linux/module.h>
14250520 LW	6	#include <linux/irq.h>
	7	#include <linux/irqchip/chained_irq.h>
	8	#include <linux/irqdomain.h>
79a9becd AC	9
	10	struct device;
	11	struct gpio_desc;
c9a9972b AC	12	struct of_phandle_args;
c9a9972b AC	13	struct device_node;
f3ed0b66	14	struct seq_file;
79a9becd	15
bb1e88cc AC	16	#ifdef CONFIG_GPIOLIB
bb1e88cc AC	17
79a9becd AC	18	/**
	19	* struct gpio_chip - abstract a GPIO controller
	20	* @label: for diagnostics
	21	* @dev: optional device providing the GPIOs
	22	* @owner: helps prevent removal of modules exporting active GPIOs
	23	* @list: links gpio_chips together for traversal
	24	* @request: optional hook for chip-specific activation, such as
	25	* enabling module power and clock; may sleep
	26	* @free: optional hook for chip-specific deactivation, such as
	27	* disabling module power and clock; may sleep
	28	* @get_direction: returns direction for signal "offset", 0=out, 1=in,
	29	* (same as GPIOF_DIR_XXX), or negative error
	30	* @direction_input: configures signal "offset" as input, or returns error
	31	* @direction_output: configures signal "offset" as output, or returns error
	32	* @get: returns value for signal "offset"; for output signals this
	33	* returns either the value actually sensed, or zero
	34	* @set: assigns output value for signal "offset"
	35	* @set_debounce: optional hook for setting debounce time for specified gpio in
	36	* interrupt triggered gpio chips
	37	* @to_irq: optional hook supporting non-static gpio_to_irq() mappings;
	38	* implementation may not sleep
	39	* @dbg_show: optional routine to show contents in debugfs; default code
	40	* will be used when this is omitted, but custom code can show extra
	41	* state (such as pullup/pulldown configuration).
	42	* @base: identifies the first GPIO number handled by this chip; or, if
	43	* negative during registration, requests dynamic ID allocation.
	44	* @ngpio: the number of GPIOs handled by this controller; the last GPIO
	45	* handled is (base + ngpio - 1).
	46	* @desc: array of ngpio descriptors. Private.
79a9becd AC	47	* @names: if set, must be an array of strings to use as alternative
	48	* names for the GPIOs in this chip. Any entry in the array
	49	* may be NULL if there is no alias for the GPIO, however the
	50	* array must be @ngpio entries long. A name can include a single printk
	51	* format specifier for an unsigned int. It is substituted by the actual
	52	* number of the gpio.
9fb1f39e	53	* @can_sleep: flag must be set iff get()/set() methods sleep, as they
1c8732bb LW	54	* must while accessing GPIO expander chips over I2C or SPI. This
	55	* implies that if the chip supports IRQs, these IRQs need to be threaded
	56	* as the chip access may sleep when e.g. reading out the IRQ status
	57	* registers.
9fb1f39e	58	* @exported: flags if the gpiochip is exported for use from sysfs. Private.
79a9becd AC	59	*
	60	* A gpio_chip can help platforms abstract various sources of GPIOs so
	61	* they can all be accessed through a common programing interface.
	62	* Example sources would be SOC controllers, FPGAs, multifunction
	63	* chips, dedicated GPIO expanders, and so on.
	64	*
	65	* Each chip controls a number of signals, identified in method calls
	66	* by "offset" values in the range 0..(@ngpio - 1). When those signals
	67	* are referenced through calls like gpio_get_value(gpio), the offset
	68	* is calculated by subtracting @base from the gpio number.
	69	*/
	70	struct gpio_chip {
	71	const char *label;
	72	struct device *dev;
	73	struct module *owner;
	74	struct list_head list;
	75
	76	int (request)(struct gpio_chip chip,
	77	unsigned offset);
	78	void (free)(struct gpio_chip chip,
	79	unsigned offset);
	80	int (get_direction)(struct gpio_chip chip,
	81	unsigned offset);
	82	int (direction_input)(struct gpio_chip chip,
	83	unsigned offset);
	84	int (direction_output)(struct gpio_chip chip,
	85	unsigned offset, int value);
	86	int (get)(struct gpio_chip chip,
	87	unsigned offset);
	88	void (set)(struct gpio_chip chip,
	89	unsigned offset, int value);
	90	int (set_debounce)(struct gpio_chip chip,
	91	unsigned offset,
	92	unsigned debounce);
	93
	94	int (to_irq)(struct gpio_chip chip,
	95	unsigned offset);
	96
	97	void (dbg_show)(struct seq_file s,
	98	struct gpio_chip *chip);
	99	int base;
	100	u16 ngpio;
	101	struct gpio_desc *desc;
	102	const char const names;
9fb1f39e LW	103	bool can_sleep;
9fb1f39e LW	104	bool exported;
79a9becd	105
14250520 LW	106	#ifdef CONFIG_GPIOLIB_IRQCHIP
	107	/*
	108	* With CONFIG_GPIO_IRQCHIP we get an irqchip inside the gpiolib
	109	* to handle IRQs for most practical cases.
	110	*/
	111	struct irq_chip *irqchip;
	112	struct irq_domain *irqdomain;
c3626fde	113	unsigned int irq_base;
14250520 LW	114	irq_flow_handler_t irq_handler;
	115	unsigned int irq_default_type;
	116	#endif
	117
79a9becd AC	118	#if defined(CONFIG_OF_GPIO)
	119	/*
	120	* If CONFIG_OF is enabled, then all GPIO controllers described in the
	121	* device tree automatically may have an OF translation
	122	*/
	123	struct device_node *of_node;
	124	int of_gpio_n_cells;
	125	int (of_xlate)(struct gpio_chip gc,
	126	const struct of_phandle_args gpiospec, u32 flags);
	127	#endif
	128	#ifdef CONFIG_PINCTRL
	129	/*
	130	* If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
	131	* describe the actual pin range which they serve in an SoC. This
	132	* information would be used by pinctrl subsystem to configure
	133	* corresponding pins for gpio usage.
	134	*/
	135	struct list_head pin_ranges;
	136	#endif
	137	};
	138
	139	extern const char gpiochip_is_requested(struct gpio_chip chip,
	140	unsigned offset);
	141
	142	/* add/remove chips */
	143	extern int gpiochip_add(struct gpio_chip *chip);
14c8a620	144	extern int gpiochip_remove(struct gpio_chip *chip);
79a9becd AC	145	extern struct gpio_chip gpiochip_find(void data,
	146	int (match)(struct gpio_chip chip, void *data));
	147
	148	/* lock/unlock as IRQ */
d74be6df AC	149	int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset);
d74be6df AC	150	void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset);
79a9becd	151
bb1e88cc AC	152	struct gpio_chip gpiod_to_chip(const struct gpio_desc desc);
bb1e88cc AC	153
14250520 LW	154	#ifdef CONFIG_GPIOLIB_IRQCHIP
	155
	156	void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
	157	struct irq_chip *irqchip,
	158	int parent_irq,
	159	irq_flow_handler_t parent_handler);
	160
	161	int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
	162	struct irq_chip *irqchip,
	163	unsigned int first_irq,
	164	irq_flow_handler_t handler,
	165	unsigned int type);
	166
	167	#endif /* CONFIG_GPIO_IRQCHIP */
	168
f7d4ad98 GR	169	int gpiochip_request_own_desc(struct gpio_desc desc, const char label);
	170	void gpiochip_free_own_desc(struct gpio_desc *desc);
	171
bb1e88cc AC	172	#else /* CONFIG_GPIOLIB */
	173
	174	static inline struct gpio_chip gpiod_to_chip(const struct gpio_desc desc)
	175	{
	176	/* GPIO can never have been requested */
	177	WARN_ON(1);
	178	return ERR_PTR(-ENODEV);
	179	}
	180
	181	#endif /* CONFIG_GPIOLIB */
	182
79a9becd	183	#endif