drivers/gpio/gpiolib.h

   1 /*
   2  * Internal GPIO functions.
   3  *
   4  * Copyright (C) 2013, Intel Corporation
   5  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #ifndef GPIOLIB_H
  13 #define GPIOLIB_H
  14
  15 #include <linux/err.h>
  16 #include <linux/device.h>
  17
  18 enum of_gpio_flags;
  19
  20 struct acpi_device;
  21
  22 /**
  23  * struct acpi_gpio_info - ACPI GPIO specific information
  24  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
  25  * @active_low: in case of @gpioint, the pin is active low
  26  */
  27 struct acpi_gpio_info {
  28         bool gpioint;
  29         bool active_low;
  30 };
  31
  32 /* gpio suffixes used for ACPI and device tree lookup */
  33 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
  34
  35 #ifdef CONFIG_ACPI
  36 void acpi_gpiochip_add(struct gpio_chip *chip);
  37 void acpi_gpiochip_remove(struct gpio_chip *chip);
  38
  39 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
  40 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
  41
  42 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
  43                                           const char *propname, int index,
  44                                           struct acpi_gpio_info *info);
  45 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
  46                                       const char *propname, int index,
  47                                       struct acpi_gpio_info *info);
  48
  49 int acpi_gpio_count(struct device *dev, const char *con_id);
  50 #else
  51 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
  52 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
  53
  54 static inline void
  55 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
  56
  57 static inline void
  58 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
  59
  60 static inline struct gpio_desc *
  61 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
  62                         int index, struct acpi_gpio_info *info)
  63 {
  64         return ERR_PTR(-ENOSYS);
  65 }
  66 static inline struct gpio_desc *
  67 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
  68                     int index, struct acpi_gpio_info *info)
  69 {
  70         return ERR_PTR(-ENXIO);
  71 }
  72 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
  73 {
  74         return -ENODEV;
  75 }
  76 #endif
  77
  78 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  79                    const char *list_name, int index, enum of_gpio_flags *flags);
  80
  81 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
  82
  83 extern struct spinlock gpio_lock;
  84 extern struct list_head gpio_chips;
  85
  86 struct gpio_desc {
  87         struct gpio_chip        *chip;
  88         unsigned long           flags;
  89 /* flag symbols are bit numbers */
  90 #define FLAG_REQUESTED  0
  91 #define FLAG_IS_OUT     1
  92 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
  93 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
  94 #define FLAG_ACTIVE_LOW 6       /* value has active low */
  95 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
  96 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
  97 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
  98 #define FLAG_IS_HOGGED  11      /* GPIO is hogged */
  99
 100         /* Connection label */
 101         const char              *label;
 102         /* Name of the GPIO */
 103         const char              *name;
 104 };
 105
 106 int gpiod_request(struct gpio_desc *desc, const char *label);
 107 void gpiod_free(struct gpio_desc *desc);
 108 int gpiod_hog(struct gpio_desc *desc, const char *name,
 109                 unsigned long lflags, enum gpiod_flags dflags);
 110
 111 /*
 112  * Return the GPIO number of the passed descriptor relative to its chip
 113  */
 114 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
 115 {
 116         return desc - &desc->chip->desc[0];
 117 }
 118
 119 /* With descriptor prefix */
 120
 121 #define gpiod_emerg(desc, fmt, ...)                                            \
 122         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 123                  ##__VA_ARGS__)
 124 #define gpiod_crit(desc, fmt, ...)                                             \
 125         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 126                  ##__VA_ARGS__)
 127 #define gpiod_err(desc, fmt, ...)                                              \
 128         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 129                  ##__VA_ARGS__)
 130 #define gpiod_warn(desc, fmt, ...)                                             \
 131         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 132                  ##__VA_ARGS__)
 133 #define gpiod_info(desc, fmt, ...)                                             \
 134         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 135                  ##__VA_ARGS__)
 136 #define gpiod_dbg(desc, fmt, ...)                                              \
 137         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 138                  ##__VA_ARGS__)
 139
 140 /* With chip prefix */
 141
 142 #define chip_emerg(chip, fmt, ...)                                      \
 143         pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 144 #define chip_crit(chip, fmt, ...)                                       \
 145         pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 146 #define chip_err(chip, fmt, ...)                                        \
 147         pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 148 #define chip_warn(chip, fmt, ...)                                       \
 149         pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 150 #define chip_info(chip, fmt, ...)                                       \
 151         pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 152 #define chip_dbg(chip, fmt, ...)                                        \
 153         pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 154
 155 #ifdef CONFIG_GPIO_SYSFS
 156
 157 int gpiochip_sysfs_register(struct gpio_chip *chip);
 158 void gpiochip_sysfs_unregister(struct gpio_chip *chip);
 159
 160 #else
 161
 162 static inline int gpiochip_sysfs_register(struct gpio_chip *chip)
 163 {
 164         return 0;
 165 }
 166
 167 static inline void gpiochip_sysfs_unregister(struct gpio_chip *chip)
 168 {
 169 }
 170
 171 #endif /* CONFIG_GPIO_SYSFS */
 172
 173 #endif /* GPIOLIB_H */