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 * @notifier: used to notify subscribers about lines being requested, released 41 * or reconfigured 42 * @pin_ranges: range of pins served by the GPIO driver 43 * 44 * This state container holds most of the runtime variable data 45 * for a GPIO device and can hold references and live on after the 46 * GPIO chip has been removed, if it is still being used from 47 * userspace. 48 */ 49 struct gpio_device { 50 int id; 51 struct device dev; 52 struct cdev chrdev; 53 struct device *mockdev; 54 struct module *owner; 55 struct gpio_chip *chip; 56 struct gpio_desc *descs; 57 int base; 58 u16 ngpio; 59 const char *label; 60 void *data; 61 struct list_head list; 62 struct blocking_notifier_head notifier; 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 /* gpio suffixes used for ACPI and device tree lookup */ 76 static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" }; 77 78 /** 79 * struct gpio_array - Opaque descriptor for a structure of GPIO array attributes 80 * 81 * @desc: Array of pointers to the GPIO descriptors 82 * @size: Number of elements in desc 83 * @chip: Parent GPIO chip 84 * @get_mask: Get mask used in fastpath 85 * @set_mask: Set mask used in fastpath 86 * @invert_mask: Invert mask used in fastpath 87 * 88 * This structure is attached to struct gpiod_descs obtained from 89 * gpiod_get_array() and can be passed back to get/set array functions in order 90 * to activate fast processing path if applicable. 91 */ 92 struct gpio_array { 93 struct gpio_desc **desc; 94 unsigned int size; 95 struct gpio_chip *chip; 96 unsigned long *get_mask; 97 unsigned long *set_mask; 98 unsigned long invert_mask[]; 99 }; 100 101 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum); 102 103 #define for_each_gpio_desc(gc, desc) \ 104 for (unsigned int __i = 0; \ 105 __i < gc->ngpio && (desc = gpiochip_get_desc(gc, __i)); \ 106 __i++) \ 107 108 #define for_each_gpio_desc_with_flag(gc, desc, flag) \ 109 for_each_gpio_desc(gc, desc) \ 110 if (!test_bit(flag, &desc->flags)) {} else 111 112 int gpiod_get_array_value_complex(bool raw, bool can_sleep, 113 unsigned int array_size, 114 struct gpio_desc **desc_array, 115 struct gpio_array *array_info, 116 unsigned long *value_bitmap); 117 int gpiod_set_array_value_complex(bool raw, bool can_sleep, 118 unsigned int array_size, 119 struct gpio_desc **desc_array, 120 struct gpio_array *array_info, 121 unsigned long *value_bitmap); 122 123 extern spinlock_t gpio_lock; 124 extern struct list_head gpio_devices; 125 126 127 /** 128 * struct gpio_desc - Opaque descriptor for a GPIO 129 * 130 * @gdev: Pointer to the parent GPIO device 131 * @flags: Binary descriptor flags 132 * @label: Name of the consumer 133 * @name: Line name 134 * @hog: Pointer to the device node that hogs this line (if any) 135 * @debounce_period_us: Debounce period in microseconds 136 * 137 * These are obtained using gpiod_get() and are preferable to the old 138 * integer-based handles. 139 * 140 * Contrary to integers, a pointer to a &struct gpio_desc is guaranteed to be 141 * valid until the GPIO is released. 142 */ 143 struct gpio_desc { 144 struct gpio_device *gdev; 145 unsigned long flags; 146 /* flag symbols are bit numbers */ 147 #define FLAG_REQUESTED 0 148 #define FLAG_IS_OUT 1 149 #define FLAG_EXPORT 2 /* protected by sysfs_lock */ 150 #define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */ 151 #define FLAG_ACTIVE_LOW 6 /* value has active low */ 152 #define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */ 153 #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ 154 #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */ 155 #define FLAG_IRQ_IS_ENABLED 10 /* GPIO is connected to an enabled IRQ */ 156 #define FLAG_IS_HOGGED 11 /* GPIO is hogged */ 157 #define FLAG_TRANSITORY 12 /* GPIO may lose value in sleep or reset */ 158 #define FLAG_PULL_UP 13 /* GPIO has pull up enabled */ 159 #define FLAG_PULL_DOWN 14 /* GPIO has pull down enabled */ 160 #define FLAG_BIAS_DISABLE 15 /* GPIO has pull disabled */ 161 #define FLAG_EDGE_RISING 16 /* GPIO CDEV detects rising edge events */ 162 #define FLAG_EDGE_FALLING 17 /* GPIO CDEV detects falling edge events */ 163 #define FLAG_EVENT_CLOCK_REALTIME 18 /* GPIO CDEV reports REALTIME timestamps in events */ 164 165 /* Connection label */ 166 const char *label; 167 /* Name of the GPIO */ 168 const char *name; 169 #ifdef CONFIG_OF_DYNAMIC 170 struct device_node *hog; 171 #endif 172 #ifdef CONFIG_GPIO_CDEV 173 /* debounce period in microseconds */ 174 unsigned int debounce_period_us; 175 #endif 176 }; 177 178 #define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) 179 180 int gpiod_request(struct gpio_desc *desc, const char *label); 181 void gpiod_free(struct gpio_desc *desc); 182 183 static inline int gpiod_request_user(struct gpio_desc *desc, const char *label) 184 { 185 int ret; 186 187 ret = gpiod_request(desc, label); 188 if (ret == -EPROBE_DEFER) 189 ret = -ENODEV; 190 191 return ret; 192 } 193 194 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, 195 unsigned long lflags, enum gpiod_flags dflags); 196 int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce); 197 int gpiod_hog(struct gpio_desc *desc, const char *name, 198 unsigned long lflags, enum gpiod_flags dflags); 199 200 /* 201 * Return the GPIO number of the passed descriptor relative to its chip 202 */ 203 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc) 204 { 205 return desc - &desc->gdev->descs[0]; 206 } 207 208 /* With descriptor prefix */ 209 210 #define gpiod_emerg(desc, fmt, ...) \ 211 pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\ 212 ##__VA_ARGS__) 213 #define gpiod_crit(desc, fmt, ...) \ 214 pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ 215 ##__VA_ARGS__) 216 #define gpiod_err(desc, fmt, ...) \ 217 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ 218 ##__VA_ARGS__) 219 #define gpiod_warn(desc, fmt, ...) \ 220 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ 221 ##__VA_ARGS__) 222 #define gpiod_info(desc, fmt, ...) \ 223 pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ 224 ##__VA_ARGS__) 225 #define gpiod_dbg(desc, fmt, ...) \ 226 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\ 227 ##__VA_ARGS__) 228 229 /* With chip prefix */ 230 231 #define chip_emerg(gc, fmt, ...) \ 232 dev_emerg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) 233 #define chip_crit(gc, fmt, ...) \ 234 dev_crit(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) 235 #define chip_err(gc, fmt, ...) \ 236 dev_err(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) 237 #define chip_warn(gc, fmt, ...) \ 238 dev_warn(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) 239 #define chip_info(gc, fmt, ...) \ 240 dev_info(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) 241 #define chip_dbg(gc, fmt, ...) \ 242 dev_dbg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__) 243 244 #endif /* GPIOLIB_H */ 245