diff options
Diffstat (limited to 'include/linux/gpio/machine.h')
| -rw-r--r-- | include/linux/gpio/machine.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/include/linux/gpio/machine.h b/include/linux/gpio/machine.h new file mode 100644 index 000000000..44e5f1629 --- /dev/null +++ b/include/linux/gpio/machine.h @@ -0,0 +1,127 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __LINUX_GPIO_MACHINE_H +#define __LINUX_GPIO_MACHINE_H + +#include <linux/types.h> + +enum gpio_lookup_flags { + GPIO_ACTIVE_HIGH = (0 << 0), + GPIO_ACTIVE_LOW = (1 << 0), + GPIO_OPEN_DRAIN = (1 << 1), + GPIO_OPEN_SOURCE = (1 << 2), + GPIO_PERSISTENT = (0 << 3), + GPIO_TRANSITORY = (1 << 3), + GPIO_PULL_UP = (1 << 4), + GPIO_PULL_DOWN = (1 << 5), + GPIO_PULL_DISABLE = (1 << 6), + + GPIO_LOOKUP_FLAGS_DEFAULT = GPIO_ACTIVE_HIGH | GPIO_PERSISTENT, +}; + +/** + * struct gpiod_lookup - lookup table + * @key: either the name of the chip the GPIO belongs to, or the GPIO line name + * Note that GPIO line names are not guaranteed to be globally unique, + * so this will use the first match found! + * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO, or + * U16_MAX to indicate that @key is a GPIO line name + * @con_id: name of the GPIO from the device's point of view + * @idx: index of the GPIO in case several GPIOs share the same name + * @flags: bitmask of gpio_lookup_flags GPIO_* values + * + * gpiod_lookup is a lookup table for associating GPIOs to specific devices and + * functions using platform data. + */ +struct gpiod_lookup { + const char *key; + u16 chip_hwnum; + const char *con_id; + unsigned int idx; + unsigned long flags; +}; + +struct gpiod_lookup_table { + struct list_head list; + const char *dev_id; + struct gpiod_lookup table[]; +}; + +/** + * struct gpiod_hog - GPIO line hog table + * @chip_label: name of the chip the GPIO belongs to + * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO + * @line_name: consumer name for the hogged line + * @lflags: bitmask of gpio_lookup_flags GPIO_* values + * @dflags: GPIO flags used to specify the direction and value + */ +struct gpiod_hog { + struct list_head list; + const char *chip_label; + u16 chip_hwnum; + const char *line_name; + unsigned long lflags; + int dflags; +}; + +/* + * Helper for lookup tables with just one single lookup for a device. + */ +#define GPIO_LOOKUP_SINGLE(_name, _dev_id, _key, _chip_hwnum, _con_id, _flags) \ +static struct gpiod_lookup_table _name = { \ + .dev_id = _dev_id, \ + .table = { \ + GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags), \ + {}, \ + }, \ +} + +/* + * Simple definition of a single GPIO under a con_id + */ +#define GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags) \ + GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, 0, _flags) + +/* + * Use this macro if you need to have several GPIOs under the same con_id. + * Each GPIO needs to use a different index and can be accessed using + * gpiod_get_index() + */ +#define GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, _idx, _flags) \ +(struct gpiod_lookup) { \ + .key = _key, \ + .chip_hwnum = _chip_hwnum, \ + .con_id = _con_id, \ + .idx = _idx, \ + .flags = _flags, \ +} + +/* + * Simple definition of a single GPIO hog in an array. + */ +#define GPIO_HOG(_chip_label, _chip_hwnum, _line_name, _lflags, _dflags) \ +(struct gpiod_hog) { \ + .chip_label = _chip_label, \ + .chip_hwnum = _chip_hwnum, \ + .line_name = _line_name, \ + .lflags = _lflags, \ + .dflags = _dflags, \ +} + +#ifdef CONFIG_GPIOLIB +void gpiod_add_lookup_table(struct gpiod_lookup_table *table); +void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n); +void gpiod_remove_lookup_table(struct gpiod_lookup_table *table); +void gpiod_add_hogs(struct gpiod_hog *hogs); +void gpiod_remove_hogs(struct gpiod_hog *hogs); +#else /* ! CONFIG_GPIOLIB */ +static inline +void gpiod_add_lookup_table(struct gpiod_lookup_table *table) {} +static inline +void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) {} +static inline +void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) {} +static inline void gpiod_add_hogs(struct gpiod_hog *hogs) {} +static inline void gpiod_remove_hogs(struct gpiod_hog *hogs) {} +#endif /* CONFIG_GPIOLIB */ + +#endif /* __LINUX_GPIO_MACHINE_H */ |