1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Based on the linux multiplexer framework
4  *
5  * Copyright (C) 2017 Axentia Technologies AB
6  * Author: Peter Rosin <peda@axentia.se>
7  *
8  * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/
9  * Jean-Jacques Hiblot <jjhiblot@ti.com>
10  */
11 
12 #ifndef _MUX_INTERNAL_H
13 #define _MUX_INTERNAL_H
14 
15 /* See mux.h for background documentation. */
16 
17 struct ofnode_phandle_args;
18 
19 /**
20  * struct mux_chip -	Represents a chip holding mux controllers.
21  * @controllers:	Number of mux controllers handled by the chip.
22  * @mux:		Array of mux controllers that are handled.
23  *
24  * This a per-device uclass-private data.
25  */
26 struct mux_chip {
27 	unsigned int controllers;
28 	struct mux_control *mux;
29 };
30 
31 /**
32  * struct mux_control_ops -	Mux controller operations for a mux chip.
33  * @set:			Set the state of the given mux controller.
34  */
35 struct mux_control_ops {
36 	/**
37 	 * set - Apply a state to a multiplexer control
38 	 *
39 	 * @mux:	A multiplexer control
40 	 * @return 0 if OK, or a negative error code.
41 	 */
42 	int (*set)(struct mux_control *mux, int state);
43 
44 	/**
45 	 * of_xlate - Translate a client's device-tree (OF) multiplexer
46 	 * specifier.
47 	 *
48 	 * If this function pointer is set to NULL, the multiplexer core will
49 	 * use a default implementation, which assumes #mux-control-cells = <1>
50 	 * and that the DT cell contains a simple integer channel ID.
51 	 *
52 	 * @dev_mux:	The multiplexer device. A single device may handle
53 	 *              several multiplexer controls.
54 	 * @args:	The multiplexer specifier values from device tree.
55 	 * @muxp:	(out) A multiplexer control
56 	 * @return 0 if OK, or a negative error code.
57 	 */
58 	int (*of_xlate)(struct mux_chip *dev_mux,
59 			struct ofnode_phandle_args *args,
60 			struct mux_control **muxp);
61 };
62 
63 /**
64  * struct mux_control -	Represents a mux controller.
65  * @in_use:		Whether the mux controller is in use or not.
66  * @dev:		The client device.
67  * @cached_state:	The current mux controller state, or -1 if none.
68  * @states:		The number of mux controller states.
69  * @idle_state:		The mux controller state to use when inactive, or one
70  *			of MUX_IDLE_AS_IS and MUX_IDLE_DISCONNECT.
71  * @id:			The index of the mux controller within the mux chip
72  *			it is a part of.
73  *
74  * Mux drivers may only change @states and @idle_state, and may only do so
75  * between allocation and registration of the mux controller. Specifically,
76  * @cached_state is internal to the mux core and should never be written by
77  * mux drivers.
78  */
79 struct mux_control {
80 	bool	in_use;
81 	struct udevice *dev;
82 	int cached_state;
83 	unsigned int states;
84 	int idle_state;
85 	int id;
86 };
87 
88 /**
89  * mux_control_get_index() - Get the index of the given mux controller
90  * @mux:		The mux-control to get the index for.
91  *
92  * Return: The index of the mux controller within the mux chip the mux
93  * controller is a part of.
94  */
mux_control_get_index(struct mux_control * mux)95 static inline unsigned int mux_control_get_index(struct mux_control *mux)
96 {
97 	return mux->id;
98 }
99 
100 /**
101  * mux_alloc_controllers() - Allocate the given number of mux controllers.
102  * @dev:		The client device.
103  * controllers:		Number of controllers to allocate.
104  *
105  * Return: 0 of OK, -errno otherwise.
106  */
107 int mux_alloc_controllers(struct udevice *dev, unsigned int controllers);
108 
109 #endif
110