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Diffstat (limited to 'include/linux/pinctrl/pinmux.h')
| -rw-r--r-- | include/linux/pinctrl/pinmux.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/include/linux/pinctrl/pinmux.h b/include/linux/pinctrl/pinmux.h new file mode 100644 index 00000000000..937b3e2fa36 --- /dev/null +++ b/include/linux/pinctrl/pinmux.h @@ -0,0 +1,142 @@ +/* + * Interface the pinmux subsystem + * + * Copyright (C) 2011 ST-Ericsson SA + * Written on behalf of Linaro for ST-Ericsson + * Based on bits of regulator core, gpio core and clk core + * + * Author: Linus Walleij <linus.walleij@linaro.org> + * + * License terms: GNU General Public License (GPL) version 2 + */ +#ifndef __LINUX_PINCTRL_PINMUX_H +#define __LINUX_PINCTRL_PINMUX_H + +#include <linux/list.h> +#include <linux/seq_file.h> +#include "pinctrl.h" + +/* This struct is private to the core and should be regarded as a cookie */ +struct pinmux; + +#ifdef CONFIG_PINMUX + +struct pinctrl_dev; + +/** + * struct pinmux_ops - pinmux operations, to be implemented by pin controller + * drivers that support pinmuxing + * @request: called by the core to see if a certain pin can be made available + * available for muxing. This is called by the core to acquire the pins + * before selecting any actual mux setting across a function. The driver + * is allowed to answer "no" by returning a negative error code + * @free: the reverse function of the request() callback, frees a pin after + * being requested + * @list_functions: list the number of selectable named functions available + * in this pinmux driver, the core will begin on 0 and call this + * repeatedly as long as it returns >= 0 to enumerate mux settings + * @get_function_name: return the function name of the muxing selector, + * called by the core to figure out which mux setting it shall map a + * certain device to + * @get_function_groups: return an array of groups names (in turn + * referencing pins) connected to a certain function selector. The group + * name can be used with the generic @pinctrl_ops to retrieve the + * actual pins affected. The applicable groups will be returned in + * @groups and the number of groups in @num_groups + * @enable: enable a certain muxing function with a certain pin group. The + * driver does not need to figure out whether enabling this function + * conflicts some other use of the pins in that group, such collisions + * are handled by the pinmux subsystem. The @func_selector selects a + * certain function whereas @group_selector selects a certain set of pins + * to be used. On simple controllers the latter argument may be ignored + * @disable: disable a certain muxing selector with a certain pin group + * @gpio_request_enable: requests and enables GPIO on a certain pin. + * Implement this only if you can mux every pin individually as GPIO. The + * affected GPIO range is passed along with an offset(pin number) into that + * specific GPIO range - function selectors and pin groups are orthogonal + * to this, the core will however make sure the pins do not collide. + * @gpio_disable_free: free up GPIO muxing on a certain pin, the reverse of + * @gpio_request_enable + * @gpio_set_direction: Since controllers may need different configurations + * depending on whether the GPIO is configured as input or output, + * a direction selector function may be implemented as a backing + * to the GPIO controllers that need pin muxing. + */ +struct pinmux_ops { + int (*request) (struct pinctrl_dev *pctldev, unsigned offset); + int (*free) (struct pinctrl_dev *pctldev, unsigned offset); + int (*list_functions) (struct pinctrl_dev *pctldev, unsigned selector); + const char *(*get_function_name) (struct pinctrl_dev *pctldev, + unsigned selector); + int (*get_function_groups) (struct pinctrl_dev *pctldev, + unsigned selector, + const char * const **groups, + unsigned * const num_groups); + int (*enable) (struct pinctrl_dev *pctldev, unsigned func_selector, + unsigned group_selector); + void (*disable) (struct pinctrl_dev *pctldev, unsigned func_selector, + unsigned group_selector); + int (*gpio_request_enable) (struct pinctrl_dev *pctldev, + struct pinctrl_gpio_range *range, + unsigned offset); + void (*gpio_disable_free) (struct pinctrl_dev *pctldev, + struct pinctrl_gpio_range *range, + unsigned offset); + int (*gpio_set_direction) (struct pinctrl_dev *pctldev, + struct pinctrl_gpio_range *range, + unsigned offset, + bool input); +}; + +/* External interface to pinmux */ +extern int pinmux_request_gpio(unsigned gpio); +extern void pinmux_free_gpio(unsigned gpio); +extern int pinmux_gpio_direction_input(unsigned gpio); +extern int pinmux_gpio_direction_output(unsigned gpio); +extern struct pinmux * __must_check pinmux_get(struct device *dev, const char *name); +extern void pinmux_put(struct pinmux *pmx); +extern int pinmux_enable(struct pinmux *pmx); +extern void pinmux_disable(struct pinmux *pmx); + +#else /* !CONFIG_PINMUX */ + +static inline int pinmux_request_gpio(unsigned gpio) +{ + return 0; +} + +static inline void pinmux_free_gpio(unsigned gpio) +{ +} + +static inline int pinmux_gpio_direction_input(unsigned gpio) +{ + return 0; +} + +static inline int pinmux_gpio_direction_output(unsigned gpio) +{ + return 0; +} + +static inline struct pinmux * __must_check pinmux_get(struct device *dev, const char *name) +{ + return NULL; +} + +static inline void pinmux_put(struct pinmux *pmx) +{ +} + +static inline int pinmux_enable(struct pinmux *pmx) +{ + return 0; +} + +static inline void pinmux_disable(struct pinmux *pmx) +{ +} + +#endif /* CONFIG_PINMUX */ + +#endif /* __LINUX_PINCTRL_PINMUX_H */ |