drivers/gpio/gpiolib.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Internal GPIO functions.
   4  *
   5  * Copyright (C) 2013, Intel Corporation
   6  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
   7  */
   8
   9 #ifndef GPIOLIB_H
  10 #define GPIOLIB_H
  11
  12 #include <linux/gpio/driver.h>
  13 #include <linux/gpio/consumer.h> /* for enum gpiod_flags */
  14 #include <linux/err.h>
  15 #include <linux/device.h>
  16 #include <linux/module.h>
  17 #include <linux/cdev.h>
  18
  19 #define GPIOCHIP_NAME   "gpiochip"
  20
  21 /**
  22  * struct gpio_device - internal state container for GPIO devices
  23  * @id: numerical ID number for the GPIO chip
  24  * @dev: the GPIO device struct
  25  * @chrdev: character device for the GPIO device
  26  * @mockdev: class device used by the deprecated sysfs interface (may be
  27  * NULL)
  28  * @owner: helps prevent removal of modules exporting active GPIOs
  29  * @chip: pointer to the corresponding gpiochip, holding static
  30  * data for this device
  31  * @descs: array of ngpio descriptors.
  32  * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
  33  * of the @descs array.
  34  * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
  35  * at device creation time.
  36  * @label: a descriptive name for the GPIO device, such as the part number
  37  * or name of the IP component in a System on Chip.
  38  * @data: per-instance data assigned by the driver
  39  * @list: links gpio_device:s together for traversal
  40  *
  41  * This state container holds most of the runtime variable data
  42  * for a GPIO device and can hold references and live on after the
  43  * GPIO chip has been removed, if it is still being used from
  44  * userspace.
  45  */
  46 struct gpio_device {
  47         int                     id;
  48         struct device           dev;
  49         struct cdev             chrdev;
  50         struct device           *mockdev;
  51         struct module           *owner;
  52         struct gpio_chip        *chip;
  53         struct gpio_desc        *descs;
  54         int                     base;
  55         u16                     ngpio;
  56         const char              *label;
  57         void                    *data;
  58         struct list_head        list;
  59         struct atomic_notifier_head notifier;
  60
  61 #ifdef CONFIG_PINCTRL
  62         /*
  63          * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
  64          * describe the actual pin range which they serve in an SoC. This
  65          * information would be used by pinctrl subsystem to configure
  66          * corresponding pins for gpio usage.
  67          */
  68         struct list_head pin_ranges;
  69 #endif
  70 };
  71
  72 /* gpio suffixes used for ACPI and device tree lookup */
  73 static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
  74
  75 struct gpio_array {
  76         struct gpio_desc        **desc;
  77         unsigned int            size;
  78         struct gpio_chip        *chip;
  79         unsigned long           *get_mask;
  80         unsigned long           *set_mask;
  81         unsigned long           invert_mask[];
  82 };
  83
  84 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
  85                                     unsigned int hwnum);
  86 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
  87                                   unsigned int array_size,
  88                                   struct gpio_desc **desc_array,
  89                                   struct gpio_array *array_info,
  90                                   unsigned long *value_bitmap);
  91 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
  92                                   unsigned int array_size,
  93                                   struct gpio_desc **desc_array,
  94                                   struct gpio_array *array_info,
  95                                   unsigned long *value_bitmap);
  96
  97 extern spinlock_t gpio_lock;
  98 extern struct list_head gpio_devices;
  99
 100 struct gpio_desc {
 101         struct gpio_device      *gdev;
 102         unsigned long           flags;
 103 /* flag symbols are bit numbers */
 104 #define FLAG_REQUESTED  0
 105 #define FLAG_IS_OUT     1
 106 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
 107 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
 108 #define FLAG_ACTIVE_LOW 6       /* value has active low */
 109 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
 110 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
 111 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
 112 #define FLAG_IRQ_IS_ENABLED 10  /* GPIO is connected to an enabled IRQ */
 113 #define FLAG_IS_HOGGED  11      /* GPIO is hogged */
 114 #define FLAG_TRANSITORY 12      /* GPIO may lose value in sleep or reset */
 115 #define FLAG_PULL_UP    13      /* GPIO has pull up enabled */
 116 #define FLAG_PULL_DOWN  14      /* GPIO has pull down enabled */
 117 #define FLAG_BIAS_DISABLE    15 /* GPIO has pull disabled */
 118
 119         /* Connection label */
 120         const char              *label;
 121         /* Name of the GPIO */
 122         const char              *name;
 123 #ifdef CONFIG_OF_DYNAMIC
 124         struct device_node      *hog;
 125 #endif
 126 };
 127
 128 int gpiod_request(struct gpio_desc *desc, const char *label);
 129 void gpiod_free(struct gpio_desc *desc);
 130 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
 131                 unsigned long lflags, enum gpiod_flags dflags);
 132 int gpiod_hog(struct gpio_desc *desc, const char *name,
 133                 unsigned long lflags, enum gpiod_flags dflags);
 134
 135 /*
 136  * Return the GPIO number of the passed descriptor relative to its chip
 137  */
 138 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
 139 {
 140         return desc - &desc->gdev->descs[0];
 141 }
 142
 143 /* With descriptor prefix */
 144
 145 #define gpiod_emerg(desc, fmt, ...)                                            \
 146         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 147                  ##__VA_ARGS__)
 148 #define gpiod_crit(desc, fmt, ...)                                             \
 149         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 150                  ##__VA_ARGS__)
 151 #define gpiod_err(desc, fmt, ...)                                              \
 152         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 153                  ##__VA_ARGS__)
 154 #define gpiod_warn(desc, fmt, ...)                                             \
 155         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 156                  ##__VA_ARGS__)
 157 #define gpiod_info(desc, fmt, ...)                                             \
 158         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 159                  ##__VA_ARGS__)
 160 #define gpiod_dbg(desc, fmt, ...)                                              \
 161         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 162                  ##__VA_ARGS__)
 163
 164 /* With chip prefix */
 165
 166 #define chip_emerg(chip, fmt, ...)                                      \
 167         dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 168 #define chip_crit(chip, fmt, ...)                                       \
 169         dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 170 #define chip_err(chip, fmt, ...)                                        \
 171         dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 172 #define chip_warn(chip, fmt, ...)                                       \
 173         dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 174 #define chip_info(chip, fmt, ...)                                       \
 175         dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 176 #define chip_dbg(chip, fmt, ...)                                        \
 177         dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 178
 179 #ifdef CONFIG_GPIO_SYSFS
 180
 181 int gpiochip_sysfs_register(struct gpio_device *gdev);
 182 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
 183
 184 #else
 185
 186 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
 187 {
 188         return 0;
 189 }
 190
 191 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
 192 {
 193 }
 194
 195 #endif /* CONFIG_GPIO_SYSFS */
 196
 197 #endif /* GPIOLIB_H */