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