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