1 /* 2 * Interface the pinmux subsystem 3 * 4 * Copyright (C) 2011 ST-Ericsson SA 5 * Written on behalf of Linaro for ST-Ericsson 6 * Based on bits of regulator core, gpio core and clk core 7 * 8 * Author: Linus Walleij <[email protected]> 9 * 10 * License terms: GNU General Public License (GPL) version 2 11 */ 12 #ifndef __LINUX_PINCTRL_PINMUX_H 13 #define __LINUX_PINCTRL_PINMUX_H 14 15 #include <linux/list.h> 16 #include <linux/seq_file.h> 17 #include "pinctrl.h" 18 19 /* This struct is private to the core and should be regarded as a cookie */ 20 struct pinmux; 21 22 #ifdef CONFIG_PINMUX 23 24 struct pinctrl_dev; 25 26 /** 27 * struct pinmux_ops - pinmux operations, to be implemented by pin controller 28 * drivers that support pinmuxing 29 * @request: called by the core to see if a certain pin can be made available 30 * available for muxing. This is called by the core to acquire the pins 31 * before selecting any actual mux setting across a function. The driver 32 * is allowed to answer "no" by returning a negative error code 33 * @free: the reverse function of the request() callback, frees a pin after 34 * being requested 35 * @list_functions: list the number of selectable named functions available 36 * in this pinmux driver, the core will begin on 0 and call this 37 * repeatedly as long as it returns >= 0 to enumerate mux settings 38 * @get_function_name: return the function name of the muxing selector, 39 * called by the core to figure out which mux setting it shall map a 40 * certain device to 41 * @get_function_groups: return an array of groups names (in turn 42 * referencing pins) connected to a certain function selector. The group 43 * name can be used with the generic @pinctrl_ops to retrieve the 44 * actual pins affected. The applicable groups will be returned in 45 * @groups and the number of groups in @num_groups 46 * @enable: enable a certain muxing function with a certain pin group. The 47 * driver does not need to figure out whether enabling this function 48 * conflicts some other use of the pins in that group, such collisions 49 * are handled by the pinmux subsystem. The @func_selector selects a 50 * certain function whereas @group_selector selects a certain set of pins 51 * to be used. On simple controllers the latter argument may be ignored 52 * @disable: disable a certain muxing selector with a certain pin group 53 * @gpio_request_enable: requests and enables GPIO on a certain pin. 54 * Implement this only if you can mux every pin individually as GPIO. The 55 * affected GPIO range is passed along with an offset(pin number) into that 56 * specific GPIO range - function selectors and pin groups are orthogonal 57 * to this, the core will however make sure the pins do not collide. 58 * @gpio_disable_free: free up GPIO muxing on a certain pin, the reverse of 59 * @gpio_request_enable 60 * @gpio_set_direction: Since controllers may need different configurations 61 * depending on whether the GPIO is configured as input or output, 62 * a direction selector function may be implemented as a backing 63 * to the GPIO controllers that need pin muxing. 64 */ 65 struct pinmux_ops { 66 int (*request) (struct pinctrl_dev *pctldev, unsigned offset); 67 int (*free) (struct pinctrl_dev *pctldev, unsigned offset); 68 int (*list_functions) (struct pinctrl_dev *pctldev, unsigned selector); 69 const char *(*get_function_name) (struct pinctrl_dev *pctldev, 70 unsigned selector); 71 int (*get_function_groups) (struct pinctrl_dev *pctldev, 72 unsigned selector, 73 const char * const **groups, 74 unsigned * const num_groups); 75 int (*enable) (struct pinctrl_dev *pctldev, unsigned func_selector, 76 unsigned group_selector); 77 void (*disable) (struct pinctrl_dev *pctldev, unsigned func_selector, 78 unsigned group_selector); 79 int (*gpio_request_enable) (struct pinctrl_dev *pctldev, 80 struct pinctrl_gpio_range *range, 81 unsigned offset); 82 void (*gpio_disable_free) (struct pinctrl_dev *pctldev, 83 struct pinctrl_gpio_range *range, 84 unsigned offset); 85 int (*gpio_set_direction) (struct pinctrl_dev *pctldev, 86 struct pinctrl_gpio_range *range, 87 unsigned offset, 88 bool input); 89 }; 90 91 /* External interface to pinmux */ 92 extern int pinmux_request_gpio(unsigned gpio); 93 extern void pinmux_free_gpio(unsigned gpio); 94 extern int pinmux_gpio_direction_input(unsigned gpio); 95 extern int pinmux_gpio_direction_output(unsigned gpio); 96 extern struct pinmux * __must_check pinmux_get(struct device *dev, const char *name); 97 extern void pinmux_put(struct pinmux *pmx); 98 extern int pinmux_enable(struct pinmux *pmx); 99 extern void pinmux_disable(struct pinmux *pmx); 100 101 #else /* !CONFIG_PINMUX */ 102 103 static inline int pinmux_request_gpio(unsigned gpio) 104 { 105 return 0; 106 } 107 108 static inline void pinmux_free_gpio(unsigned gpio) 109 { 110 } 111 112 static inline int pinmux_gpio_direction_input(unsigned gpio) 113 { 114 return 0; 115 } 116 117 static inline int pinmux_gpio_direction_output(unsigned gpio) 118 { 119 return 0; 120 } 121 122 static inline struct pinmux * __must_check pinmux_get(struct device *dev, const char *name) 123 { 124 return NULL; 125 } 126 127 static inline void pinmux_put(struct pinmux *pmx) 128 { 129 } 130 131 static inline int pinmux_enable(struct pinmux *pmx) 132 { 133 return 0; 134 } 135 136 static inline void pinmux_disable(struct pinmux *pmx) 137 { 138 } 139 140 #endif /* CONFIG_PINMUX */ 141 142 #endif /* __LINUX_PINCTRL_PINMUX_H */ 143