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  * @flags: GPIO initialization flags
  79  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
  80  * @polarity: interrupt polarity as provided by ACPI
  81  * @triggering: triggering type as provided by ACPI
  82  */
  83 struct acpi_gpio_info {
  84         enum gpiod_flags flags;
  85         bool gpioint;
  86         int polarity;
  87         int triggering;
  88 };
  89
  90 /* gpio suffixes used for ACPI and device tree lookup */
  91 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
  92
  93 #ifdef CONFIG_OF_GPIO
  94 struct gpio_desc *of_find_gpio(struct device *dev,
  95                                const char *con_id,
  96                                unsigned int idx,
  97                                enum gpio_lookup_flags *flags);
  98 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  99                    const char *list_name, int index, enum of_gpio_flags *flags);
 100 int of_gpiochip_add(struct gpio_chip *gc);
 101 void of_gpiochip_remove(struct gpio_chip *gc);
 102 #else
 103 static inline struct gpio_desc *of_find_gpio(struct device *dev,
 104                                              const char *con_id,
 105                                              unsigned int idx,
 106                                              enum gpio_lookup_flags *flags)
 107 {
 108         return ERR_PTR(-ENOENT);
 109 }
 110 static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
 111                    const char *list_name, int index, enum of_gpio_flags *flags)
 112 {
 113         return ERR_PTR(-ENOENT);
 114 }
 115 static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
 116 static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
 117 #endif /* CONFIG_OF_GPIO */
 118
 119 #ifdef CONFIG_ACPI
 120 void acpi_gpiochip_add(struct gpio_chip *chip);
 121 void acpi_gpiochip_remove(struct gpio_chip *chip);
 122
 123 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
 124 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
 125
 126 int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
 127                                  enum gpiod_flags update);
 128
 129 struct gpio_desc *acpi_find_gpio(struct device *dev,
 130                                  const char *con_id,
 131                                  unsigned int idx,
 132                                  enum gpiod_flags *dflags,
 133                                  enum gpio_lookup_flags *lookupflags);
 134 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
 135                                       const char *propname, int index,
 136                                       struct acpi_gpio_info *info);
 137
 138 int acpi_gpio_count(struct device *dev, const char *con_id);
 139
 140 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
 141 #else
 142 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
 143 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
 144
 145 static inline void
 146 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
 147
 148 static inline void
 149 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
 150
 151 static inline int
 152 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
 153 {
 154         return 0;
 155 }
 156
 157 static inline struct gpio_desc *
 158 acpi_find_gpio(struct device *dev, const char *con_id,
 159                unsigned int idx, enum gpiod_flags *dflags,
 160                enum gpio_lookup_flags *lookupflags)
 161 {
 162         return ERR_PTR(-ENOENT);
 163 }
 164 static inline struct gpio_desc *
 165 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
 166                     int index, struct acpi_gpio_info *info)
 167 {
 168         return ERR_PTR(-ENXIO);
 169 }
 170 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
 171 {
 172         return -ENODEV;
 173 }
 174
 175 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
 176                                             const char *con_id)
 177 {
 178         return false;
 179 }
 180 #endif
 181
 182 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
 183 void gpiod_set_array_value_complex(bool raw, bool can_sleep,
 184                                    unsigned int array_size,
 185                                    struct gpio_desc **desc_array,
 186                                    int *value_array);
 187
 188 extern struct spinlock gpio_lock;
 189 extern struct list_head gpio_devices;
 190
 191 struct gpio_desc {
 192         struct gpio_device      *gdev;
 193         unsigned long           flags;
 194 /* flag symbols are bit numbers */
 195 #define FLAG_REQUESTED  0
 196 #define FLAG_IS_OUT     1
 197 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
 198 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
 199 #define FLAG_ACTIVE_LOW 6       /* value has active low */
 200 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
 201 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
 202 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
 203 #define FLAG_IS_HOGGED  11      /* GPIO is hogged */
 204 #define FLAG_SLEEP_MAY_LOOSE_VALUE 12   /* GPIO may loose value in sleep */
 205
 206         /* Connection label */
 207         const char              *label;
 208         /* Name of the GPIO */
 209         const char              *name;
 210 };
 211
 212 int gpiod_request(struct gpio_desc *desc, const char *label);
 213 void gpiod_free(struct gpio_desc *desc);
 214 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
 215                 unsigned long lflags, enum gpiod_flags dflags);
 216 int gpiod_hog(struct gpio_desc *desc, const char *name,
 217                 unsigned long lflags, enum gpiod_flags dflags);
 218
 219 /*
 220  * Return the GPIO number of the passed descriptor relative to its chip
 221  */
 222 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
 223 {
 224         return desc - &desc->gdev->descs[0];
 225 }
 226
 227 void devprop_gpiochip_set_names(struct gpio_chip *chip);
 228
 229 /* With descriptor prefix */
 230
 231 #define gpiod_emerg(desc, fmt, ...)                                            \
 232         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 233                  ##__VA_ARGS__)
 234 #define gpiod_crit(desc, fmt, ...)                                             \
 235         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 236                  ##__VA_ARGS__)
 237 #define gpiod_err(desc, fmt, ...)                                              \
 238         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 239                  ##__VA_ARGS__)
 240 #define gpiod_warn(desc, fmt, ...)                                             \
 241         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 242                  ##__VA_ARGS__)
 243 #define gpiod_info(desc, fmt, ...)                                             \
 244         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 245                  ##__VA_ARGS__)
 246 #define gpiod_dbg(desc, fmt, ...)                                              \
 247         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 248                  ##__VA_ARGS__)
 249
 250 /* With chip prefix */
 251
 252 #define chip_emerg(chip, fmt, ...)                                      \
 253         dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 254 #define chip_crit(chip, fmt, ...)                                       \
 255         dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 256 #define chip_err(chip, fmt, ...)                                        \
 257         dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 258 #define chip_warn(chip, fmt, ...)                                       \
 259         dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 260 #define chip_info(chip, fmt, ...)                                       \
 261         dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 262 #define chip_dbg(chip, fmt, ...)                                        \
 263         dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
 264
 265 #ifdef CONFIG_GPIO_SYSFS
 266
 267 int gpiochip_sysfs_register(struct gpio_device *gdev);
 268 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
 269
 270 #else
 271
 272 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
 273 {
 274         return 0;
 275 }
 276
 277 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
 278 {
 279 }
 280
 281 #endif /* CONFIG_GPIO_SYSFS */
 282
 283 #endif /* GPIOLIB_H */