/* SPDX-License-Identifier: GPL-2.0 */ /* * Internal GPIO functions. * * Copyright (C) 2013, Intel Corporation * Author: Mika Westerberg */ #ifndef GPIOLIB_H #define GPIOLIB_H #include #include #include #include /* for enum gpiod_flags */ #include #include #include #include #include #define GPIOCHIP_NAME "gpiochip" /** * struct gpio_device - internal state container for GPIO devices * @dev: the GPIO device struct * @chrdev: character device for the GPIO device * @id: numerical ID number for the GPIO chip * @mockdev: class device used by the deprecated sysfs interface (may be * NULL) * @owner: helps prevent removal of modules exporting active GPIOs * @chip: pointer to the corresponding gpiochip, holding static * data for this device * @descs: array of ngpio descriptors. * @desc_srcu: ensures consistent state of GPIO descriptors exposed to users * @ngpio: the number of GPIO lines on this GPIO device, equal to the size * of the @descs array. * @can_sleep: indicate whether the GPIO chip driver's callbacks can sleep * implying that they cannot be used from atomic context * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned * at device creation time. * @label: a descriptive name for the GPIO device, such as the part number * or name of the IP component in a System on Chip. * @data: per-instance data assigned by the driver * @list: links gpio_device:s together for traversal * @line_state_notifier: used to notify subscribers about lines being * requested, released or reconfigured * @line_state_wq: used to emit line state events from a separate thread in * process context * @device_notifier: used to notify character device wait queues about the GPIO * device being unregistered * @srcu: protects the pointer to the underlying GPIO chip * @pin_ranges: range of pins served by the GPIO driver * * This state container holds most of the runtime variable data * for a GPIO device and can hold references and live on after the * GPIO chip has been removed, if it is still being used from * userspace. */ struct gpio_device { struct device dev; struct cdev chrdev; int id; struct device *mockdev; struct module *owner; struct gpio_chip __rcu *chip; struct gpio_desc *descs; struct srcu_struct desc_srcu; unsigned int base; u16 ngpio; bool can_sleep; const char *label; void *data; struct list_head list; struct atomic_notifier_head line_state_notifier; struct workqueue_struct *line_state_wq; struct blocking_notifier_head device_notifier; struct srcu_struct srcu; #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 }; static inline struct gpio_device *to_gpio_device(struct device *dev) { return container_of(dev, struct gpio_device, dev); } /* GPIO suffixes used for ACPI and device tree lookup */ extern const char *const gpio_suffixes[]; #define for_each_gpio_property_name(propname, con_id) \ for (const char * const *__suffixes = gpio_suffixes; \ *__suffixes && ({ \ const char *__gs = *__suffixes; \ \ if (con_id) \ snprintf(propname, sizeof(propname), "%s-%s", con_id, __gs); \ else \ snprintf(propname, sizeof(propname), "%s", __gs); \ 1; \ }); \ __suffixes++) /** * struct gpio_array - Opaque descriptor for a structure of GPIO array attributes * * @desc: Array of pointers to the GPIO descriptors * @size: Number of elements in desc * @chip: Parent GPIO chip * @get_mask: Get mask used in fastpath * @set_mask: Set mask used in fastpath * @invert_mask: Invert mask used in fastpath * * This structure is attached to struct gpiod_descs obtained from * gpiod_get_array() and can be passed back to get/set array functions in order * to activate fast processing path if applicable. */ struct gpio_array { struct gpio_desc **desc; unsigned int size; struct gpio_chip *chip; unsigned long *get_mask; unsigned long *set_mask; unsigned long invert_mask[]; }; #define for_each_gpio_desc(gc, desc) \ for (unsigned int __i = 0; \ __i < gc->ngpio && (desc = gpiochip_get_desc(gc, __i)); \ __i++) \ #define for_each_gpio_desc_with_flag(gc, desc, flag) \ for_each_gpio_desc(gc, desc) \ if (!test_bit(flag, &desc->flags)) {} else int gpiod_get_array_value_complex(bool raw, bool can_sleep, unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap); int gpiod_set_array_value_complex(bool raw, bool can_sleep, unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap); int gpiod_set_transitory(struct gpio_desc *desc, bool transitory); void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action); int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value); int gpiod_direction_input_nonotify(struct gpio_desc *desc); struct gpio_desc_label { struct rcu_head rh; char str[]; }; /** * struct gpio_desc - Opaque descriptor for a GPIO * * @gdev: Pointer to the parent GPIO device * @flags: Binary descriptor flags * @label: Name of the consumer * @name: Line name * @hog: Pointer to the device node that hogs this line (if any) * @debounce_period_us: Debounce period in microseconds * * These are obtained using gpiod_get() and are preferable to the old * integer-based handles. * * Contrary to integers, a pointer to a &struct gpio_desc is guaranteed to be * valid until the GPIO is released. */ struct gpio_desc { struct gpio_device *gdev; unsigned long flags; /* flag symbols are bit numbers */ #define FLAG_REQUESTED 0 #define FLAG_IS_OUT 1 #define FLAG_EXPORT 2 /* protected by sysfs_lock */ #define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */ #define FLAG_ACTIVE_LOW 6 /* value has active low */ #define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */ #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */ #define FLAG_IRQ_IS_ENABLED 10 /* GPIO is connected to an enabled IRQ */ #define FLAG_IS_HOGGED 11 /* GPIO is hogged */ #define FLAG_TRANSITORY 12 /* GPIO may lose value in sleep or reset */ #define FLAG_PULL_UP 13 /* GPIO has pull up enabled */ #define FLAG_PULL_DOWN 14 /* GPIO has pull down enabled */ #define FLAG_BIAS_DISABLE 15 /* GPIO has pull disabled */ #define FLAG_EDGE_RISING 16 /* GPIO CDEV detects rising edge events */ #define FLAG_EDGE_FALLING 17 /* GPIO CDEV detects falling edge events */ #define FLAG_EVENT_CLOCK_REALTIME 18 /* GPIO CDEV reports REALTIME timestamps in events */ #define FLAG_EVENT_CLOCK_HTE 19 /* GPIO CDEV reports hardware timestamps in events */ /* Connection label */ struct gpio_desc_label __rcu *label; /* Name of the GPIO */ const char *name; #ifdef CONFIG_OF_DYNAMIC struct device_node *hog; #endif #ifdef CONFIG_GPIO_CDEV /* debounce period in microseconds */ unsigned int debounce_period_us; #endif }; #define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) struct gpio_chip_guard { struct gpio_device *gdev; struct gpio_chip *gc; int idx; }; DEFINE_CLASS(gpio_chip_guard, struct gpio_chip_guard, srcu_read_unlock(&_T.gdev->srcu, _T.idx), ({ struct gpio_chip_guard _guard; _guard.gdev = desc->gdev; _guard.idx = srcu_read_lock(&_guard.gdev->srcu); _guard.gc = srcu_dereference(_guard.gdev->chip, &_guard.gdev->srcu); _guard; }), struct gpio_desc *desc) int gpiod_request(struct gpio_desc *desc, const char *label); void gpiod_free(struct gpio_desc *desc); static inline int gpiod_request_user(struct gpio_desc *desc, const char *label) { int ret; ret = gpiod_request(desc, label); if (ret == -EPROBE_DEFER) ret = -ENODEV; return ret; } struct gpio_desc *gpiod_find_and_request(struct device *consumer, struct fwnode_handle *fwnode, const char *con_id, unsigned int idx, enum gpiod_flags flags, const char *label, bool platform_lookup_allowed); int gpio_do_set_config(struct gpio_desc *desc, unsigned long config); int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, unsigned long lflags, enum gpiod_flags dflags); int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce); int gpiod_hog(struct gpio_desc *desc, const char *name, unsigned long lflags, enum gpiod_flags dflags); int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev); struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum); const char *gpiod_get_label(struct gpio_desc *desc); /* * Return the GPIO number of the passed descriptor relative to its chip */ static inline int gpio_chip_hwgpio(const struct gpio_desc *desc) { return desc - &desc->gdev->descs[0]; } /* With descriptor prefix */ #define gpiod_err(desc, fmt, ...) \ do { \ scoped_guard(srcu, &desc->gdev->desc_srcu) { \ pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), \ gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \ } \ } while (0) #define gpiod_warn(desc, fmt, ...) \ do { \ scoped_guard(srcu, &desc->gdev->desc_srcu) { \ pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), \ gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \ } \ } while (0) #define gpiod_dbg(desc, fmt, ...) \ do { \ scoped_guard(srcu, &desc->gdev->desc_srcu) { \ pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), \ gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \ } \ } while (0) /* With chip prefix */ #define chip_err(gc, fmt, ...) \ dev_err(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) #define chip_warn(gc, fmt, ...) \ dev_warn(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) #define chip_info(gc, fmt, ...) \ dev_info(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) #define chip_dbg(gc, fmt, ...) \ dev_dbg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) #endif /* GPIOLIB_H */