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/list.h>
15 #include <linux/seq_file.h>
16 #include <linux/pinctrl/pinctrl.h>
17
18 struct pinctrl_dev;
19
20 /**
21 * struct pinmux_ops - pinmux operations, to be implemented by pin controller
22 * drivers that support pinmuxing
23 * @request: called by the core to see if a certain pin can be made
24 * available for muxing. This is called by the core to acquire the pins
25 * before selecting any actual mux setting across a function. The driver
26 * is allowed to answer "no" by returning a negative error code
27 * @free: the reverse function of the request() callback, frees a pin after
28 * being requested
29 * @get_functions_count: returns number of selectable named functions available
30 * in this pinmux driver
31 * @get_function_name: return the function name of the muxing selector,
32 * called by the core to figure out which mux setting it shall map a
33 * certain device to
34 * @get_function_groups: return an array of groups names (in turn
35 * referencing pins) connected to a certain function selector. The group
36 * name can be used with the generic @pinctrl_ops to retrieve the
37 * actual pins affected. The applicable groups will be returned in
38 * @groups and the number of groups in @num_groups
39 * @set_mux: enable a certain muxing function with a certain pin group. The
40 * driver does not need to figure out whether enabling this function
41 * conflicts some other use of the pins in that group, such collisions
42 * are handled by the pinmux subsystem. The @func_selector selects a
43 * certain function whereas @group_selector selects a certain set of pins
44 * to be used. On simple controllers the latter argument may be ignored
45 * @gpio_request_enable: requests and enables GPIO on a certain pin.
46 * Implement this only if you can mux every pin individually as GPIO. The
47 * affected GPIO range is passed along with an offset(pin number) into that
48 * specific GPIO range - function selectors and pin groups are orthogonal
49 * to this, the core will however make sure the pins do not collide.
50 * @gpio_disable_free: free up GPIO muxing on a certain pin, the reverse of
51 * @gpio_request_enable
52 * @gpio_set_direction: Since controllers may need different configurations
53 * depending on whether the GPIO is configured as input or output,
54 * a direction selector function may be implemented as a backing
55 * to the GPIO controllers that need pin muxing.
56 * @strict: do not allow simultaneous use of the same pin for GPIO and another
57 * function. Check both gpio_owner and mux_owner strictly before approving
58 * the pin request.
59 */
60 struct pinmux_ops {
61 int (*request) (struct pinctrl_dev *pctldev, unsigned offset);
62 int (*free) (struct pinctrl_dev *pctldev, unsigned offset);
63 int (*get_functions_count) (struct pinctrl_dev *pctldev);
64 const char *(*get_function_name) (struct pinctrl_dev *pctldev,
65 unsigned selector);
66 int (*get_function_groups) (struct pinctrl_dev *pctldev,
67 unsigned selector,
68 const char * const **groups,
69 unsigned *num_groups);
70 int (*set_mux) (struct pinctrl_dev *pctldev, unsigned func_selector,
71 unsigned group_selector);
72 int (*gpio_request_enable) (struct pinctrl_dev *pctldev,
73 struct pinctrl_gpio_range *range,
74 unsigned offset);
75 void (*gpio_disable_free) (struct pinctrl_dev *pctldev,
76 struct pinctrl_gpio_range *range,
77 unsigned offset);
78 int (*gpio_set_direction) (struct pinctrl_dev *pctldev,
79 struct pinctrl_gpio_range *range,
80 unsigned offset,
81 bool input);
82 bool strict;
83 };
84
85 #endif /* __LINUX_PINCTRL_PINMUX_H */