1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Interface the pinmux subsystem 4 * 5 * Copyright (C) 2011 ST-Ericsson SA 6 * Written on behalf of Linaro for ST-Ericsson 7 * Based on bits of regulator core, gpio core and clk core 8 * 9 * Author: Linus Walleij <linus.walleij@linaro.org> 10 */ 11 #ifndef __LINUX_PINCTRL_PINMUX_H 12 #define __LINUX_PINCTRL_PINMUX_H 13 14 #include <linux/types.h> 15 16 struct pinctrl_dev; 17 struct pinctrl_gpio_range; 18 19 /** 20 * struct pinmux_ops - pinmux operations, to be implemented by pin controller 21 * drivers that support pinmuxing 22 * @request: called by the core to see if a certain pin can be made 23 * available for muxing. This is called by the core to acquire the pins 24 * before selecting any actual mux setting across a function. The driver 25 * is allowed to answer "no" by returning a negative error code 26 * @free: the reverse function of the request() callback, frees a pin after 27 * being requested 28 * @get_functions_count: returns number of selectable named functions available 29 * in this pinmux driver 30 * @get_function_name: return the function name of the muxing selector, 31 * called by the core to figure out which mux setting it shall map a 32 * certain device to 33 * @get_function_groups: return an array of groups names (in turn 34 * referencing pins) connected to a certain function selector. The group 35 * name can be used with the generic @pinctrl_ops to retrieve the 36 * actual pins affected. The applicable groups will be returned in 37 * @groups and the number of groups in @num_groups 38 * @function_is_gpio: determine if the indicated function selector passed 39 * corresponds to the GPIO function which is used by the accelerated GPIO 40 * functions @gpio_request_enable, @gpio_disable_free and 41 * @gpio_set_direction. When the pin control core can properly determine 42 * if a function is a GPIO function, it is easier to use the @strict mode 43 * on the pin controller. Since a single function is passed, this is 44 * only useful on pin controllers that use a specific function for GPIO, 45 * and that usually presupposes that a one-group-per-pin approach is 46 * used, so that a single function can be set on a single pin to turn 47 * it to GPIO mode. 48 * @set_mux: enable a certain muxing function with a certain pin group. The 49 * driver does not need to figure out whether enabling this function 50 * conflicts some other use of the pins in that group, such collisions 51 * are handled by the pinmux subsystem. The @func_selector selects a 52 * certain function whereas @group_selector selects a certain set of pins 53 * to be used. On simple controllers the latter argument may be ignored 54 * @gpio_request_enable: requests and enables GPIO on a certain pin. 55 * Implement this only if you can mux every pin individually as GPIO. The 56 * affected GPIO range is passed along with an offset(pin number) into that 57 * specific GPIO range - function selectors and pin groups are orthogonal 58 * to this, the core will however make sure the pins do not collide. 59 * @gpio_disable_free: free up GPIO muxing on a certain pin, the reverse of 60 * @gpio_request_enable 61 * @gpio_set_direction: Since controllers may need different configurations 62 * depending on whether the GPIO is configured as input or output, 63 * a direction selector function may be implemented as a backing 64 * to the GPIO controllers that need pin muxing. 65 * @strict: do not allow simultaneous use of the same pin for GPIO and another 66 * function. Check both gpio_owner and mux_owner strictly before approving 67 * the pin request. 68 */ 69 struct pinmux_ops { 70 int (*request) (struct pinctrl_dev *pctldev, unsigned int offset); 71 int (*free) (struct pinctrl_dev *pctldev, unsigned int offset); 72 int (*get_functions_count) (struct pinctrl_dev *pctldev); 73 const char *(*get_function_name) (struct pinctrl_dev *pctldev, 74 unsigned int selector); 75 int (*get_function_groups) (struct pinctrl_dev *pctldev, 76 unsigned int selector, 77 const char * const **groups, 78 unsigned int *num_groups); 79 bool (*function_is_gpio) (struct pinctrl_dev *pctldev, 80 unsigned int selector); 81 int (*set_mux) (struct pinctrl_dev *pctldev, unsigned int func_selector, 82 unsigned int group_selector); 83 int (*gpio_request_enable) (struct pinctrl_dev *pctldev, 84 struct pinctrl_gpio_range *range, 85 unsigned int offset); 86 void (*gpio_disable_free) (struct pinctrl_dev *pctldev, 87 struct pinctrl_gpio_range *range, 88 unsigned int offset); 89 int (*gpio_set_direction) (struct pinctrl_dev *pctldev, 90 struct pinctrl_gpio_range *range, 91 unsigned int offset, 92 bool input); 93 bool strict; 94 }; 95 96 #endif /* __LINUX_PINCTRL_PINMUX_H */ 97