Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1 | #ifndef __LINUX_GPIO_DRIVER_H |
| 2 | #define __LINUX_GPIO_DRIVER_H |
| 3 | |
| 4 | #include <linux/types.h> |
| 5 | |
| 6 | struct device; |
| 7 | struct gpio_desc; |
Stephen Rothwell | f3ed0b6 | 2013-10-29 01:06:23 +1100 | [diff] [blame^] | 8 | struct seq_file; |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 9 | |
| 10 | /** |
| 11 | * struct gpio_chip - abstract a GPIO controller |
| 12 | * @label: for diagnostics |
| 13 | * @dev: optional device providing the GPIOs |
| 14 | * @owner: helps prevent removal of modules exporting active GPIOs |
| 15 | * @list: links gpio_chips together for traversal |
| 16 | * @request: optional hook for chip-specific activation, such as |
| 17 | * enabling module power and clock; may sleep |
| 18 | * @free: optional hook for chip-specific deactivation, such as |
| 19 | * disabling module power and clock; may sleep |
| 20 | * @get_direction: returns direction for signal "offset", 0=out, 1=in, |
| 21 | * (same as GPIOF_DIR_XXX), or negative error |
| 22 | * @direction_input: configures signal "offset" as input, or returns error |
| 23 | * @direction_output: configures signal "offset" as output, or returns error |
| 24 | * @get: returns value for signal "offset"; for output signals this |
| 25 | * returns either the value actually sensed, or zero |
| 26 | * @set: assigns output value for signal "offset" |
| 27 | * @set_debounce: optional hook for setting debounce time for specified gpio in |
| 28 | * interrupt triggered gpio chips |
| 29 | * @to_irq: optional hook supporting non-static gpio_to_irq() mappings; |
| 30 | * implementation may not sleep |
| 31 | * @dbg_show: optional routine to show contents in debugfs; default code |
| 32 | * will be used when this is omitted, but custom code can show extra |
| 33 | * state (such as pullup/pulldown configuration). |
| 34 | * @base: identifies the first GPIO number handled by this chip; or, if |
| 35 | * negative during registration, requests dynamic ID allocation. |
| 36 | * @ngpio: the number of GPIOs handled by this controller; the last GPIO |
| 37 | * handled is (base + ngpio - 1). |
| 38 | * @desc: array of ngpio descriptors. Private. |
| 39 | * @can_sleep: flag must be set iff get()/set() methods sleep, as they |
| 40 | * must while accessing GPIO expander chips over I2C or SPI |
| 41 | * @names: if set, must be an array of strings to use as alternative |
| 42 | * names for the GPIOs in this chip. Any entry in the array |
| 43 | * may be NULL if there is no alias for the GPIO, however the |
| 44 | * array must be @ngpio entries long. A name can include a single printk |
| 45 | * format specifier for an unsigned int. It is substituted by the actual |
| 46 | * number of the gpio. |
| 47 | * |
| 48 | * A gpio_chip can help platforms abstract various sources of GPIOs so |
| 49 | * they can all be accessed through a common programing interface. |
| 50 | * Example sources would be SOC controllers, FPGAs, multifunction |
| 51 | * chips, dedicated GPIO expanders, and so on. |
| 52 | * |
| 53 | * Each chip controls a number of signals, identified in method calls |
| 54 | * by "offset" values in the range 0..(@ngpio - 1). When those signals |
| 55 | * are referenced through calls like gpio_get_value(gpio), the offset |
| 56 | * is calculated by subtracting @base from the gpio number. |
| 57 | */ |
| 58 | struct gpio_chip { |
| 59 | const char *label; |
| 60 | struct device *dev; |
| 61 | struct module *owner; |
| 62 | struct list_head list; |
| 63 | |
| 64 | int (*request)(struct gpio_chip *chip, |
| 65 | unsigned offset); |
| 66 | void (*free)(struct gpio_chip *chip, |
| 67 | unsigned offset); |
| 68 | int (*get_direction)(struct gpio_chip *chip, |
| 69 | unsigned offset); |
| 70 | int (*direction_input)(struct gpio_chip *chip, |
| 71 | unsigned offset); |
| 72 | int (*direction_output)(struct gpio_chip *chip, |
| 73 | unsigned offset, int value); |
| 74 | int (*get)(struct gpio_chip *chip, |
| 75 | unsigned offset); |
| 76 | void (*set)(struct gpio_chip *chip, |
| 77 | unsigned offset, int value); |
| 78 | int (*set_debounce)(struct gpio_chip *chip, |
| 79 | unsigned offset, |
| 80 | unsigned debounce); |
| 81 | |
| 82 | int (*to_irq)(struct gpio_chip *chip, |
| 83 | unsigned offset); |
| 84 | |
| 85 | void (*dbg_show)(struct seq_file *s, |
| 86 | struct gpio_chip *chip); |
| 87 | int base; |
| 88 | u16 ngpio; |
| 89 | struct gpio_desc *desc; |
| 90 | const char *const *names; |
| 91 | unsigned can_sleep:1; |
| 92 | unsigned exported:1; |
| 93 | |
| 94 | #if defined(CONFIG_OF_GPIO) |
| 95 | /* |
| 96 | * If CONFIG_OF is enabled, then all GPIO controllers described in the |
| 97 | * device tree automatically may have an OF translation |
| 98 | */ |
| 99 | struct device_node *of_node; |
| 100 | int of_gpio_n_cells; |
| 101 | int (*of_xlate)(struct gpio_chip *gc, |
| 102 | const struct of_phandle_args *gpiospec, u32 *flags); |
| 103 | #endif |
| 104 | #ifdef CONFIG_PINCTRL |
| 105 | /* |
| 106 | * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally |
| 107 | * describe the actual pin range which they serve in an SoC. This |
| 108 | * information would be used by pinctrl subsystem to configure |
| 109 | * corresponding pins for gpio usage. |
| 110 | */ |
| 111 | struct list_head pin_ranges; |
| 112 | #endif |
| 113 | }; |
| 114 | |
| 115 | extern const char *gpiochip_is_requested(struct gpio_chip *chip, |
| 116 | unsigned offset); |
| 117 | |
| 118 | /* add/remove chips */ |
| 119 | extern int gpiochip_add(struct gpio_chip *chip); |
| 120 | extern int __must_check gpiochip_remove(struct gpio_chip *chip); |
| 121 | extern struct gpio_chip *gpiochip_find(void *data, |
| 122 | int (*match)(struct gpio_chip *chip, void *data)); |
| 123 | |
| 124 | /* lock/unlock as IRQ */ |
| 125 | int gpiod_lock_as_irq(struct gpio_desc *desc); |
| 126 | void gpiod_unlock_as_irq(struct gpio_desc *desc); |
| 127 | |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 128 | /** |
| 129 | * Lookup table for associating GPIOs to specific devices and functions using |
| 130 | * platform data. |
| 131 | */ |
| 132 | struct gpiod_lookup { |
| 133 | struct list_head list; |
| 134 | /* |
| 135 | * name of the chip the GPIO belongs to |
| 136 | */ |
| 137 | const char *chip_label; |
| 138 | /* |
| 139 | * hardware number (i.e. relative to the chip) of the GPIO |
| 140 | */ |
| 141 | u16 chip_hwnum; |
| 142 | /* |
| 143 | * name of device that can claim this GPIO |
| 144 | */ |
| 145 | const char *dev_id; |
| 146 | /* |
| 147 | * name of the GPIO from the device's point of view |
| 148 | */ |
| 149 | const char *con_id; |
| 150 | /* |
| 151 | * index of the GPIO in case several GPIOs share the same name |
| 152 | */ |
| 153 | unsigned int idx; |
| 154 | /* |
| 155 | * mask of GPIOF_* values |
| 156 | */ |
| 157 | unsigned long flags; |
| 158 | }; |
| 159 | |
| 160 | /* |
| 161 | * Simple definition of a single GPIO under a con_id |
| 162 | */ |
| 163 | #define GPIO_LOOKUP(_chip_label, _chip_hwnum, _dev_id, _con_id, _flags) \ |
| 164 | GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _dev_id, _con_id, 0, _flags) |
| 165 | |
| 166 | /* |
| 167 | * Use this macro if you need to have several GPIOs under the same con_id. |
| 168 | * Each GPIO needs to use a different index and can be accessed using |
| 169 | * gpiod_get_index() |
| 170 | */ |
| 171 | #define GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _dev_id, _con_id, _idx, \ |
| 172 | _flags) \ |
| 173 | { \ |
| 174 | .chip_label = _chip_label, \ |
| 175 | .chip_hwnum = _chip_hwnum, \ |
| 176 | .dev_id = _dev_id, \ |
| 177 | .con_id = _con_id, \ |
| 178 | .idx = _idx, \ |
| 179 | .flags = _flags, \ |
| 180 | } |
| 181 | |
| 182 | void gpiod_add_table(struct gpiod_lookup *table, size_t size); |
| 183 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 184 | #endif |