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 #ifdef CONFIG_ACPI
  33 void acpi_gpiochip_add(struct gpio_chip *chip);
  34 void acpi_gpiochip_remove(struct gpio_chip *chip);
  35
  36 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
  37 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
  38
  39 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
  40                                           const char *propname, int index,
  41                                           struct acpi_gpio_info *info);
  42 #else
  43 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
  44 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
  45
  46 static inline void
  47 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
  48
  49 static inline void
  50 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
  51
  52 static inline struct gpio_desc *
  53 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
  54                         int index, struct acpi_gpio_info *info)
  55 {
  56         return ERR_PTR(-ENOSYS);
  57 }
  58 #endif
  59
  60 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  61                    const char *list_name, int index, enum of_gpio_flags *flags);
  62
  63 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
  64
  65 extern struct spinlock gpio_lock;
  66 extern struct list_head gpio_chips;
  67
  68 struct gpio_desc {
  69         struct gpio_chip        *chip;
  70         unsigned long           flags;
  71 /* flag symbols are bit numbers */
  72 #define FLAG_REQUESTED  0
  73 #define FLAG_IS_OUT     1
  74 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
  75 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
  76 #define FLAG_TRIG_FALL  4       /* trigger on falling edge */
  77 #define FLAG_TRIG_RISE  5       /* trigger on rising edge */
  78 #define FLAG_ACTIVE_LOW 6       /* value has active low */
  79 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
  80 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
  81 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
  82 #define FLAG_SYSFS_DIR  10      /* show sysfs direction attribute */
  83
  84 #define ID_SHIFT        16      /* add new flags before this one */
  85
  86 #define GPIO_FLAGS_MASK         ((1 << ID_SHIFT) - 1)
  87 #define GPIO_TRIGGER_MASK       (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE))
  88
  89         const char              *label;
  90 };
  91
  92 int gpiod_request(struct gpio_desc *desc, const char *label);
  93 void gpiod_free(struct gpio_desc *desc);
  94
  95 /*
  96  * Return the GPIO number of the passed descriptor relative to its chip
  97  */
  98 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
  99 {
 100         return desc - &desc->chip->desc[0];
 101 }
 102
 103 /* With descriptor prefix */
 104
 105 #define gpiod_emerg(desc, fmt, ...)                                            \
 106         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 107                  ##__VA_ARGS__)
 108 #define gpiod_crit(desc, fmt, ...)                                             \
 109         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 110                  ##__VA_ARGS__)
 111 #define gpiod_err(desc, fmt, ...)                                              \
 112         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 113                  ##__VA_ARGS__)
 114 #define gpiod_warn(desc, fmt, ...)                                             \
 115         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 116                  ##__VA_ARGS__)
 117 #define gpiod_info(desc, fmt, ...)                                             \
 118         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 119                  ##__VA_ARGS__)
 120 #define gpiod_dbg(desc, fmt, ...)                                              \
 121         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 122                  ##__VA_ARGS__)
 123
 124 /* With chip prefix */
 125
 126 #define chip_emerg(chip, fmt, ...)                                      \
 127         pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 128 #define chip_crit(chip, fmt, ...)                                       \
 129         pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 130 #define chip_err(chip, fmt, ...)                                        \
 131         pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 132 #define chip_warn(chip, fmt, ...)                                       \
 133         pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 134 #define chip_info(chip, fmt, ...)                                       \
 135         pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 136 #define chip_dbg(chip, fmt, ...)                                        \
 137         pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 138
 139 #ifdef CONFIG_GPIO_SYSFS
 140
 141 int gpiochip_export(struct gpio_chip *chip);
 142 void gpiochip_unexport(struct gpio_chip *chip);
 143
 144 #else
 145
 146 static inline int gpiochip_export(struct gpio_chip *chip)
 147 {
 148         return 0;
 149 }
 150
 151 static inline void gpiochip_unexport(struct gpio_chip *chip)
 152 {
 153 }
 154
 155 #endif /* CONFIG_GPIO_SYSFS */
 156
 157 #endif /* GPIOLIB_H */