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 <linus.walleij@linaro.org>
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 <linux/pinctrl/pinctrl.h>
18
19#ifdef CONFIG_PINMUX
20
21struct pinctrl_dev;
22
23/**
24 * struct pinmux_ops - pinmux operations, to be implemented by pin controller
25 * drivers that support pinmuxing
26 * @request: called by the core to see if a certain pin can be made
27 *	available for muxing. This is called by the core to acquire the pins
28 *	before selecting any actual mux setting across a function. The driver
29 *	is allowed to answer "no" by returning a negative error code
30 * @free: the reverse function of the request() callback, frees a pin after
31 *	being requested
32 * @get_functions_count: returns number of selectable named functions available
33 *	in this pinmux driver
34 * @get_function_name: return the function name of the muxing selector,
35 *	called by the core to figure out which mux setting it shall map a
36 *	certain device to
37 * @get_function_groups: return an array of groups names (in turn
38 *	referencing pins) connected to a certain function selector. The group
39 *	name can be used with the generic @pinctrl_ops to retrieve the
40 *	actual pins affected. The applicable groups will be returned in
41 *	@groups and the number of groups in @num_groups
42 * @set_mux: enable a certain muxing function with a certain pin group. The
43 *	driver does not need to figure out whether enabling this function
44 *	conflicts some other use of the pins in that group, such collisions
45 *	are handled by the pinmux subsystem. The @func_selector selects a
46 *	certain function whereas @group_selector selects a certain set of pins
47 *	to be used. On simple controllers the latter argument may be ignored
48 * @gpio_request_enable: requests and enables GPIO on a certain pin.
49 *	Implement this only if you can mux every pin individually as GPIO. The
50 *	affected GPIO range is passed along with an offset(pin number) into that
51 *	specific GPIO range - function selectors and pin groups are orthogonal
52 *	to this, the core will however make sure the pins do not collide.
53 * @gpio_disable_free: free up GPIO muxing on a certain pin, the reverse of
54 *	@gpio_request_enable
55 * @gpio_set_direction: Since controllers may need different configurations
56 *	depending on whether the GPIO is configured as input or output,
57 *	a direction selector function may be implemented as a backing
58 *	to the GPIO controllers that need pin muxing.
59 */
60struct 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 * const 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};
83
84#endif /* CONFIG_PINMUX */
85
86#endif /* __LINUX_PINCTRL_PINMUX_H */
87