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 /**
  21  * struct acpi_gpio_info - ACPI GPIO specific information
  22  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
  23  * @active_low: in case of @gpioint, the pin is active low
  24  */
  25 struct acpi_gpio_info {
  26         bool gpioint;
  27         bool active_low;
  28 };
  29
  30 #ifdef CONFIG_ACPI
  31 void acpi_gpiochip_add(struct gpio_chip *chip);
  32 void acpi_gpiochip_remove(struct gpio_chip *chip);
  33
  34 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
  35 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
  36
  37 struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index,
  38                                           struct acpi_gpio_info *info);
  39 #else
  40 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
  41 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
  42
  43 static inline void
  44 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
  45
  46 static inline void
  47 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
  48
  49 static inline struct gpio_desc *
  50 acpi_get_gpiod_by_index(struct device *dev, int index,
  51                         struct acpi_gpio_info *info)
  52 {
  53         return ERR_PTR(-ENOSYS);
  54 }
  55 #endif
  56
  57 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  58                    const char *list_name, int index, enum of_gpio_flags *flags);
  59
  60 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
  61
  62 extern struct spinlock gpio_lock;
  63 extern struct list_head gpio_chips;
  64
  65 struct gpio_desc {
  66         struct gpio_chip        *chip;
  67         unsigned long           flags;
  68 /* flag symbols are bit numbers */
  69 #define FLAG_REQUESTED  0
  70 #define FLAG_IS_OUT     1
  71 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
  72 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
  73 #define FLAG_TRIG_FALL  4       /* trigger on falling edge */
  74 #define FLAG_TRIG_RISE  5       /* trigger on rising edge */
  75 #define FLAG_ACTIVE_LOW 6       /* value has active low */
  76 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
  77 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
  78 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
  79
  80 #define ID_SHIFT        16      /* add new flags before this one */
  81
  82 #define GPIO_FLAGS_MASK         ((1 << ID_SHIFT) - 1)
  83 #define GPIO_TRIGGER_MASK       (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE))
  84
  85         const char              *label;
  86 };
  87
  88 int gpiod_request(struct gpio_desc *desc, const char *label);
  89 void gpiod_free(struct gpio_desc *desc);
  90
  91 /*
  92  * Return the GPIO number of the passed descriptor relative to its chip
  93  */
  94 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
  95 {
  96         return desc - &desc->chip->desc[0];
  97 }
  98
  99 /* With descriptor prefix */
 100
 101 #define gpiod_emerg(desc, fmt, ...)                                            \
 102         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 103                  ##__VA_ARGS__)
 104 #define gpiod_crit(desc, fmt, ...)                                             \
 105         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 106                  ##__VA_ARGS__)
 107 #define gpiod_err(desc, fmt, ...)                                              \
 108         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 109                  ##__VA_ARGS__)
 110 #define gpiod_warn(desc, fmt, ...)                                             \
 111         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 112                  ##__VA_ARGS__)
 113 #define gpiod_info(desc, fmt, ...)                                             \
 114         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 115                  ##__VA_ARGS__)
 116 #define gpiod_dbg(desc, fmt, ...)                                              \
 117         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 118                  ##__VA_ARGS__)
 119
 120 /* With chip prefix */
 121
 122 #define chip_emerg(chip, fmt, ...)                                      \
 123         pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 124 #define chip_crit(chip, fmt, ...)                                       \
 125         pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 126 #define chip_err(chip, fmt, ...)                                        \
 127         pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 128 #define chip_warn(chip, fmt, ...)                                       \
 129         pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 130 #define chip_info(chip, fmt, ...)                                       \
 131         pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 132 #define chip_dbg(chip, fmt, ...)                                        \
 133         pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 134
 135 #ifdef CONFIG_GPIO_SYSFS
 136
 137 int gpiochip_export(struct gpio_chip *chip);
 138 void gpiochip_unexport(struct gpio_chip *chip);
 139
 140 #else
 141
 142 static inline int gpiochip_export(struct gpio_chip *chip)
 143 {
 144         return 0;
 145 }
 146
 147 static inline void gpiochip_unexport(struct gpio_chip *chip)
 148 {
 149 }
 150
 151 #endif /* CONFIG_GPIO_SYSFS */
 152
 153 #endif /* GPIOLIB_H */