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/gpio/driver.h>
  16 #include <linux/err.h>
  17 #include <linux/device.h>
  18 #include <linux/module.h>
  19 #include <linux/cdev.h>
  20
  21 enum of_gpio_flags;
  22 enum gpiod_flags;
  23 enum gpio_lookup_flags;
  24 struct acpi_device;
  25
  26 /**
  27  * struct gpio_device - internal state container for GPIO devices
  28  * @id: numerical ID number for the GPIO chip
  29  * @dev: the GPIO device struct
  30  * @chrdev: character device for the GPIO device
  31  * @mockdev: class device used by the deprecated sysfs interface (may be
  32  * NULL)
  33  * @owner: helps prevent removal of modules exporting active GPIOs
  34  * @chip: pointer to the corresponding gpiochip, holding static
  35  * data for this device
  36  * @descs: array of ngpio descriptors.
  37  * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
  38  * of the @descs array.
  39  * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
  40  * at device creation time.
  41  * @label: a descriptive name for the GPIO device, such as the part number
  42  * or name of the IP component in a System on Chip.
  43  * @data: per-instance data assigned by the driver
  44  * @list: links gpio_device:s together for traversal
  45  *
  46  * This state container holds most of the runtime variable data
  47  * for a GPIO device and can hold references and live on after the
  48  * GPIO chip has been removed, if it is still being used from
  49  * userspace.
  50  */
  51 struct gpio_device {
  52         int                     id;
  53         struct device           dev;
  54         struct cdev             chrdev;
  55         struct device           *mockdev;
  56         struct module           *owner;
  57         struct gpio_chip        *chip;
  58         struct gpio_desc        *descs;
  59         int                     base;
  60         u16                     ngpio;
  61         char                    *label;
  62         void                    *data;
  63         struct list_head        list;
  64
  65 #ifdef CONFIG_PINCTRL
  66         /*
  67          * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
  68          * describe the actual pin range which they serve in an SoC. This
  69          * information would be used by pinctrl subsystem to configure
  70          * corresponding pins for gpio usage.
  71          */
  72         struct list_head pin_ranges;
  73 #endif
  74 };
  75
  76 /**
  77  * struct acpi_gpio_info - ACPI GPIO specific information
  78  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
  79  * @active_low: in case of @gpioint, the pin is active low
  80  */
  81 struct acpi_gpio_info {
  82         bool gpioint;
  83         int polarity;
  84         int triggering;
  85 };
  86
  87 /* gpio suffixes used for ACPI and device tree lookup */
  88 static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
  89
  90 #ifdef CONFIG_OF_GPIO
  91 struct gpio_desc *of_find_gpio(struct device *dev,
  92                                const char *con_id,
  93                                unsigned int idx,
  94                                enum gpio_lookup_flags *flags);
  95 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  96                    const char *list_name, int index, enum of_gpio_flags *flags);
  97 int of_gpiochip_add(struct gpio_chip *gc);
  98 void of_gpiochip_remove(struct gpio_chip *gc);
  99 #else
 100 static inline struct gpio_desc *of_find_gpio(struct device *dev,
 101                                              const char *con_id,
 102                                              unsigned int idx,
 103                                              enum gpio_lookup_flags *flags)
 104 {
 105         return ERR_PTR(-ENOENT);
 106 }
 107 static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
 108                    const char *list_name, int index, enum of_gpio_flags *flags)
 109 {
 110         return ERR_PTR(-ENOENT);
 111 }
 112 static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
 113 static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
 114 #endif /* CONFIG_OF_GPIO */
 115
 116 #ifdef CONFIG_ACPI
 117 void acpi_gpiochip_add(struct gpio_chip *chip);
 118 void acpi_gpiochip_remove(struct gpio_chip *chip);
 119
 120 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
 121 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
 122
 123 struct gpio_desc *acpi_find_gpio(struct device *dev,
 124                                  const char *con_id,
 125                                  unsigned int idx,
 126                                  enum gpiod_flags flags,
 127                                  enum gpio_lookup_flags *lookupflags);
 128 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
 129                                       const char *propname, int index,
 130                                       struct acpi_gpio_info *info);
 131
 132 int acpi_gpio_count(struct device *dev, const char *con_id);
 133
 134 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
 135 #else
 136 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
 137 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
 138
 139 static inline void
 140 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
 141
 142 static inline void
 143 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
 144
 145 static inline struct gpio_desc *
 146 acpi_find_gpio(struct device *dev, const char *con_id,
 147                unsigned int idx, enum gpiod_flags flags,
 148                enum gpio_lookup_flags *lookupflags)
 149 {
 150         return ERR_PTR(-ENOENT);
 151 }
 152 static inline struct gpio_desc *
 153 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
 154                     int index, struct acpi_gpio_info *info)
 155 {
 156         return ERR_PTR(-ENXIO);
 157 }
 158 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
 159 {
 160         return -ENODEV;
 161 }
 162
 163 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
 164                                             const char *con_id)
 165 {
 166         return false;
 167 }
 168 #endif
 169
 170 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
 171 void gpiod_set_array_value_complex(bool raw, bool can_sleep,
 172                                    unsigned int array_size,
 173                                    struct gpio_desc **desc_array,
 174                                    int *value_array);
 175
 176 extern struct spinlock gpio_lock;
 177 extern struct list_head gpio_devices;
 178
 179 struct gpio_desc {
 180         struct gpio_device      *gdev;
 181         unsigned long           flags;
 182 /* flag symbols are bit numbers */
 183 #define FLAG_REQUESTED  0
 184 #define FLAG_IS_OUT     1
 185 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
 186 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
 187 #define FLAG_ACTIVE_LOW 6       /* value has active low */
 188 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
 189 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
 190 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
 191 #define FLAG_IS_HOGGED  11      /* GPIO is hogged */
 192
 193         /* Connection label */
 194         const char              *label;
 195         /* Name of the GPIO */
 196         const char              *name;
 197 };
 198
 199 int gpiod_request(struct gpio_desc *desc, const char *label);
 200 void gpiod_free(struct gpio_desc *desc);
 201 int gpiod_hog(struct gpio_desc *desc, const char *name,
 202                 unsigned long lflags, enum gpiod_flags dflags);
 203
 204 /*
 205  * Return the GPIO number of the passed descriptor relative to its chip
 206  */
 207 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
 208 {
 209         return desc - &desc->gdev->descs[0];
 210 }
 211
 212 /* With descriptor prefix */
 213
 214 #define gpiod_emerg(desc, fmt, ...)                                            \
 215         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 216                  ##__VA_ARGS__)
 217 #define gpiod_crit(desc, fmt, ...)                                             \
 218         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 219                  ##__VA_ARGS__)
 220 #define gpiod_err(desc, fmt, ...)                                              \
 221         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 222                  ##__VA_ARGS__)
 223 #define gpiod_warn(desc, fmt, ...)                                             \
 224         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 225                  ##__VA_ARGS__)
 226 #define gpiod_info(desc, fmt, ...)                                             \
 227         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 228                  ##__VA_ARGS__)
 229 #define gpiod_dbg(desc, fmt, ...)                                              \
 230         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 231                  ##__VA_ARGS__)
 232
 233 /* With chip prefix */
 234
 235 #define chip_emerg(chip, fmt, ...)                                      \
 236         dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 237 #define chip_crit(chip, fmt, ...)                                       \
 238         dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 239 #define chip_err(chip, fmt, ...)                                        \
 240         dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 241 #define chip_warn(chip, fmt, ...)                                       \
 242         dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 243 #define chip_info(chip, fmt, ...)                                       \
 244         dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 245 #define chip_dbg(chip, fmt, ...)                                        \
 246         dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 247
 248 #ifdef CONFIG_GPIO_SYSFS
 249
 250 int gpiochip_sysfs_register(struct gpio_device *gdev);
 251 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
 252
 253 #else
 254
 255 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
 256 {
 257         return 0;
 258 }
 259
 260 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
 261 {
 262 }
 263
 264 #endif /* CONFIG_GPIO_SYSFS */
 265
 266 #endif /* GPIOLIB_H */