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
  46 int acpi_gpio_count(struct device *dev, const char *con_id);
  47 #else
  48 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
  49 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
  50
  51 static inline void
  52 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
  53
  54 static inline void
  55 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
  56
  57 static inline struct gpio_desc *
  58 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
  59                         int index, struct acpi_gpio_info *info)
  60 {
  61         return ERR_PTR(-ENOSYS);
  62 }
  63
  64 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
  65 {
  66         return -ENODEV;
  67 }
  68 #endif
  69
  70 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  71                    const char *list_name, int index, enum of_gpio_flags *flags);
  72
  73 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
  74
  75 extern struct spinlock gpio_lock;
  76 extern struct list_head gpio_chips;
  77
  78 struct gpio_desc {
  79         struct gpio_chip        *chip;
  80         unsigned long           flags;
  81 /* flag symbols are bit numbers */
  82 #define FLAG_REQUESTED  0
  83 #define FLAG_IS_OUT     1
  84 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
  85 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
  86 #define FLAG_TRIG_FALL  4       /* trigger on falling edge */
  87 #define FLAG_TRIG_RISE  5       /* trigger on rising edge */
  88 #define FLAG_ACTIVE_LOW 6       /* value has active low */
  89 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
  90 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
  91 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
  92 #define FLAG_SYSFS_DIR  10      /* show sysfs direction attribute */
  93 #define FLAG_IS_HOGGED  11      /* GPIO is hogged */
  94
  95 #define ID_SHIFT        16      /* add new flags before this one */
  96
  97 #define GPIO_FLAGS_MASK         ((1 << ID_SHIFT) - 1)
  98 #define GPIO_TRIGGER_MASK       (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE))
  99
 100         const char              *label;
 101 };
 102
 103 int gpiod_request(struct gpio_desc *desc, const char *label);
 104 void gpiod_free(struct gpio_desc *desc);
 105 int gpiod_hog(struct gpio_desc *desc, const char *name,
 106                 unsigned long lflags, enum gpiod_flags dflags);
 107
 108 /*
 109  * Return the GPIO number of the passed descriptor relative to its chip
 110  */
 111 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
 112 {
 113         return desc - &desc->chip->desc[0];
 114 }
 115
 116 /* With descriptor prefix */
 117
 118 #define gpiod_emerg(desc, fmt, ...)                                            \
 119         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 120                  ##__VA_ARGS__)
 121 #define gpiod_crit(desc, fmt, ...)                                             \
 122         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 123                  ##__VA_ARGS__)
 124 #define gpiod_err(desc, fmt, ...)                                              \
 125         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 126                  ##__VA_ARGS__)
 127 #define gpiod_warn(desc, fmt, ...)                                             \
 128         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 129                  ##__VA_ARGS__)
 130 #define gpiod_info(desc, fmt, ...)                                             \
 131         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 132                  ##__VA_ARGS__)
 133 #define gpiod_dbg(desc, fmt, ...)                                              \
 134         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 135                  ##__VA_ARGS__)
 136
 137 /* With chip prefix */
 138
 139 #define chip_emerg(chip, fmt, ...)                                      \
 140         pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 141 #define chip_crit(chip, fmt, ...)                                       \
 142         pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 143 #define chip_err(chip, fmt, ...)                                        \
 144         pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 145 #define chip_warn(chip, fmt, ...)                                       \
 146         pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 147 #define chip_info(chip, fmt, ...)                                       \
 148         pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 149 #define chip_dbg(chip, fmt, ...)                                        \
 150         pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 151
 152 #ifdef CONFIG_GPIO_SYSFS
 153
 154 int gpiochip_export(struct gpio_chip *chip);
 155 void gpiochip_unexport(struct gpio_chip *chip);
 156
 157 #else
 158
 159 static inline int gpiochip_export(struct gpio_chip *chip)
 160 {
 161         return 0;
 162 }
 163
 164 static inline void gpiochip_unexport(struct gpio_chip *chip)
 165 {
 166 }
 167
 168 #endif /* CONFIG_GPIO_SYSFS */
 169
 170 #endif /* GPIOLIB_H */