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 enum gpiod_flags;
  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         int polarity;
  30         int triggering;
  31 };
  32
  33 /* gpio suffixes used for ACPI and device tree lookup */
  34 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
  35
  36 #ifdef CONFIG_ACPI
  37 void acpi_gpiochip_add(struct gpio_chip *chip);
  38 void acpi_gpiochip_remove(struct gpio_chip *chip);
  39
  40 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
  41 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
  42
  43 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
  44                                           const char *propname, int index,
  45                                           struct acpi_gpio_info *info);
  46 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
  47                                       const char *propname, int index,
  48                                       struct acpi_gpio_info *info);
  49
  50 int acpi_gpio_count(struct device *dev, const char *con_id);
  51
  52 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
  53 #else
  54 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
  55 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
  56
  57 static inline void
  58 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
  59
  60 static inline void
  61 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
  62
  63 static inline struct gpio_desc *
  64 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
  65                         int index, struct acpi_gpio_info *info)
  66 {
  67         return ERR_PTR(-ENOSYS);
  68 }
  69 static inline struct gpio_desc *
  70 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
  71                     int index, struct acpi_gpio_info *info)
  72 {
  73         return ERR_PTR(-ENXIO);
  74 }
  75 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
  76 {
  77         return -ENODEV;
  78 }
  79
  80 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
  81                                             const char *con_id)
  82 {
  83         return false;
  84 }
  85 #endif
  86
  87 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  88                    const char *list_name, int index, enum of_gpio_flags *flags);
  89
  90 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
  91
  92 extern struct spinlock gpio_lock;
  93 extern struct list_head gpio_chips;
  94
  95 struct gpio_desc {
  96         struct gpio_chip        *chip;
  97         unsigned long           flags;
  98 /* flag symbols are bit numbers */
  99 #define FLAG_REQUESTED  0
 100 #define FLAG_IS_OUT     1
 101 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
 102 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
 103 #define FLAG_ACTIVE_LOW 6       /* value has active low */
 104 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
 105 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
 106 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
 107 #define FLAG_IS_HOGGED  11      /* GPIO is hogged */
 108
 109         /* Connection label */
 110         const char              *label;
 111         /* Name of the GPIO */
 112         const char              *name;
 113 };
 114
 115 int gpiod_request(struct gpio_desc *desc, const char *label);
 116 void gpiod_free(struct gpio_desc *desc);
 117 int gpiod_hog(struct gpio_desc *desc, const char *name,
 118                 unsigned long lflags, enum gpiod_flags dflags);
 119
 120 /*
 121  * Return the GPIO number of the passed descriptor relative to its chip
 122  */
 123 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
 124 {
 125         return desc - &desc->chip->desc[0];
 126 }
 127
 128 /* With descriptor prefix */
 129
 130 #define gpiod_emerg(desc, fmt, ...)                                            \
 131         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 132                  ##__VA_ARGS__)
 133 #define gpiod_crit(desc, fmt, ...)                                             \
 134         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 135                  ##__VA_ARGS__)
 136 #define gpiod_err(desc, fmt, ...)                                              \
 137         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 138                  ##__VA_ARGS__)
 139 #define gpiod_warn(desc, fmt, ...)                                             \
 140         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 141                  ##__VA_ARGS__)
 142 #define gpiod_info(desc, fmt, ...)                                             \
 143         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 144                  ##__VA_ARGS__)
 145 #define gpiod_dbg(desc, fmt, ...)                                              \
 146         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 147                  ##__VA_ARGS__)
 148
 149 /* With chip prefix */
 150
 151 #define chip_emerg(chip, fmt, ...)                                      \
 152         pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 153 #define chip_crit(chip, fmt, ...)                                       \
 154         pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 155 #define chip_err(chip, fmt, ...)                                        \
 156         pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 157 #define chip_warn(chip, fmt, ...)                                       \
 158         pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 159 #define chip_info(chip, fmt, ...)                                       \
 160         pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 161 #define chip_dbg(chip, fmt, ...)                                        \
 162         pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 163
 164 #ifdef CONFIG_GPIO_SYSFS
 165
 166 int gpiochip_sysfs_register(struct gpio_chip *chip);
 167 void gpiochip_sysfs_unregister(struct gpio_chip *chip);
 168
 169 #else
 170
 171 static inline int gpiochip_sysfs_register(struct gpio_chip *chip)
 172 {
 173         return 0;
 174 }
 175
 176 static inline void gpiochip_sysfs_unregister(struct gpio_chip *chip)
 177 {
 178 }
 179
 180 #endif /* CONFIG_GPIO_SYSFS */
 181
 182 #endif /* GPIOLIB_H */