#ifndef _ASM_GENERIC_GPIO_H
#define _ASM_GENERIC_GPIO_H
-#ifdef CONFIG_HAVE_GPIO_LIB
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+
+#ifdef CONFIG_GPIOLIB
+
+#include <linux/compiler.h>
/* Platforms may implement their GPIO interface with library code,
* at a small performance cost for non-inlined operations and some
*
* 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.
+ * smaller range 0..ARCH_NR_GPIOS-1.
*/
#ifndef ARCH_NR_GPIOS
return ((unsigned)number) < ARCH_NR_GPIOS;
}
+struct device;
struct seq_file;
struct module;
/**
* 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
+ * @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
* @direction_input: configures signal "offset" as input, or returns error
* @get: returns value for signal "offset"; for output signals this
* returns either the value actually sensed, or zero
* @direction_output: configures signal "offset" as output, or returns error
* @set: assigns output value for signal "offset"
+ * @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).
* handled is (base + ngpio - 1).
* @can_sleep: flag must be set iff get()/set() methods sleep, as they
* must while accessing GPIO expander chips over I2C or SPI
+ * @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 gpio_chip can help platforms abstract various sources of GPIOs so
* they can all be accessed through a common programing interface.
* is calculated by subtracting @base from the gpio number.
*/
struct gpio_chip {
- char *label;
+ const char *label;
+ struct device *dev;
struct module *owner;
+ int (*request)(struct gpio_chip *chip,
+ unsigned offset);
+ void (*free)(struct gpio_chip *chip,
+ unsigned offset);
+
int (*direction_input)(struct gpio_chip *chip,
unsigned offset);
int (*get)(struct gpio_chip *chip,
unsigned offset, int value);
void (*set)(struct gpio_chip *chip,
unsigned offset, int value);
+
+ int (*to_irq)(struct gpio_chip *chip,
+ unsigned offset);
+
void (*dbg_show)(struct seq_file *s,
struct gpio_chip *chip);
int base;
u16 ngpio;
+ char **names;
unsigned can_sleep:1;
+ unsigned exported:1;
};
extern const char *gpiochip_is_requested(struct gpio_chip *chip,
unsigned offset);
-extern int __init __must_check gpiochip_reserve(int start, int ngpio);
+extern int __must_check gpiochip_reserve(int start, int ngpio);
/* add/remove chips */
extern int gpiochip_add(struct gpio_chip *chip);
extern int __gpio_cansleep(unsigned gpio);
+extern int __gpio_to_irq(unsigned gpio);
+
+#define GPIOF_DIR_OUT (0 << 0)
+#define GPIOF_DIR_IN (1 << 0)
+
+#define GPIOF_INIT_LOW (0 << 1)
+#define GPIOF_INIT_HIGH (1 << 1)
+
+#define GPIOF_IN (GPIOF_DIR_IN)
+#define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW)
+#define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
+
+/**
+ * struct gpio - a structure describing a GPIO with configuration
+ * @gpio: the GPIO number
+ * @flags: GPIO configuration as specified by GPIOF_*
+ * @label: a literal description string of this GPIO
+ */
+struct gpio {
+ unsigned gpio;
+ unsigned long flags;
+ const char *label;
+};
+
+extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
+extern int gpio_request_array(struct gpio *array, size_t num);
+extern void gpio_free_array(struct gpio *array, size_t num);
+
+#ifdef CONFIG_GPIO_SYSFS
+
+/*
+ * A sysfs interface can be exported by individual drivers if they want,
+ * but more typically is configured entirely from userspace.
+ */
+extern int gpio_export(unsigned gpio, bool direction_may_change);
+extern int gpio_export_link(struct device *dev, const char *name,
+ unsigned gpio);
+extern int gpio_sysfs_set_active_low(unsigned gpio, int value);
+extern void gpio_unexport(unsigned gpio);
+
+#endif /* CONFIG_GPIO_SYSFS */
-#else
+#else /* !CONFIG_HAVE_GPIO_LIB */
static inline int gpio_is_valid(int number)
{
gpio_set_value(gpio, value);
}
-#endif
+#endif /* !CONFIG_HAVE_GPIO_LIB */
+
+#ifndef CONFIG_GPIO_SYSFS
+
+struct device;
+
+/* sysfs support is only available with gpiolib, where it's optional */
+
+static inline int gpio_export(unsigned gpio, bool direction_may_change)
+{
+ return -ENOSYS;
+}
+
+static inline int gpio_export_link(struct device *dev, const char *name,
+ unsigned gpio)
+{
+ return -ENOSYS;
+}
+
+static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
+{
+ return -ENOSYS;
+}
+
+static inline void gpio_unexport(unsigned gpio)
+{
+}
+#endif /* CONFIG_GPIO_SYSFS */
#endif /* _ASM_GENERIC_GPIO_H */