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-rw-r--r--include/linux/gpio/driver.h239
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diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
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+++ b/include/linux/gpio/driver.h
@@ -0,0 +1,239 @@
+#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>
+#include <linux/pinctrl/pinctrl.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_multiple: assigns output values for multiple signals defined by "mask"
+ * @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.
+ * @irq_not_threaded: flag must be set if @can_sleep is set but the
+ * IRQs don't need to be threaded
+ *
+ * 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);
+ void (*set_multiple)(struct gpio_chip *chip,
+ unsigned long *mask,
+ unsigned long *bits);
+ 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 irq_not_threaded;
+ bool exported;
+
+#ifdef CONFIG_GPIOLIB_IRQCHIP
+ /*
+ * With CONFIG_GPIOLIB_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 void 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 gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset);
+void gpiochip_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_GPIOLIB_IRQCHIP */
+
+#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 */
+
+struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
+ 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