xref: /OK3568_Linux_fs/u-boot/include/reset-uclass.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (c) 2016, NVIDIA CORPORATION.
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * SPDX-License-Identifier: GPL-2.0
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #ifndef _RESET_UCLASS_H
8*4882a593Smuzhiyun #define _RESET_UCLASS_H
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun /* See reset.h for background documentation. */
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <reset.h>
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun struct ofnode_phandle_args;
15*4882a593Smuzhiyun struct udevice;
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun /**
18*4882a593Smuzhiyun  * struct reset_ops - The functions that a reset controller driver must
19*4882a593Smuzhiyun  * implement.
20*4882a593Smuzhiyun  */
21*4882a593Smuzhiyun struct reset_ops {
22*4882a593Smuzhiyun 	/**
23*4882a593Smuzhiyun 	 * of_xlate - Translate a client's device-tree (OF) reset specifier.
24*4882a593Smuzhiyun 	 *
25*4882a593Smuzhiyun 	 * The reset core calls this function as the first step in implementing
26*4882a593Smuzhiyun 	 * a client's reset_get_by_*() call.
27*4882a593Smuzhiyun 	 *
28*4882a593Smuzhiyun 	 * If this function pointer is set to NULL, the reset core will use a
29*4882a593Smuzhiyun 	 * default implementation, which assumes #reset-cells = <1>, and that
30*4882a593Smuzhiyun 	 * the DT cell contains a simple integer reset signal ID.
31*4882a593Smuzhiyun 	 *
32*4882a593Smuzhiyun 	 * At present, the reset API solely supports device-tree. If this
33*4882a593Smuzhiyun 	 * changes, other xxx_xlate() functions may be added to support those
34*4882a593Smuzhiyun 	 * other mechanisms.
35*4882a593Smuzhiyun 	 *
36*4882a593Smuzhiyun 	 * @reset_ctl:	The reset control struct to hold the translation result.
37*4882a593Smuzhiyun 	 * @args:	The reset specifier values from device tree.
38*4882a593Smuzhiyun 	 * @return 0 if OK, or a negative error code.
39*4882a593Smuzhiyun 	 */
40*4882a593Smuzhiyun 	int (*of_xlate)(struct reset_ctl *reset_ctl,
41*4882a593Smuzhiyun 			struct ofnode_phandle_args *args);
42*4882a593Smuzhiyun 	/**
43*4882a593Smuzhiyun 	 * request - Request a translated reset control.
44*4882a593Smuzhiyun 	 *
45*4882a593Smuzhiyun 	 * The reset core calls this function as the second step in
46*4882a593Smuzhiyun 	 * implementing a client's reset_get_by_*() call, following a
47*4882a593Smuzhiyun 	 * successful xxx_xlate() call.
48*4882a593Smuzhiyun 	 *
49*4882a593Smuzhiyun 	 * @reset_ctl:	The reset control struct to request; this has been
50*4882a593Smuzhiyun 	 *		filled in by a previoux xxx_xlate() function call.
51*4882a593Smuzhiyun 	 * @return 0 if OK, or a negative error code.
52*4882a593Smuzhiyun 	 */
53*4882a593Smuzhiyun 	int (*request)(struct reset_ctl *reset_ctl);
54*4882a593Smuzhiyun 	/**
55*4882a593Smuzhiyun 	 * free - Free a previously requested reset control.
56*4882a593Smuzhiyun 	 *
57*4882a593Smuzhiyun 	 * This is the implementation of the client reset_free() API.
58*4882a593Smuzhiyun 	 *
59*4882a593Smuzhiyun 	 * @reset_ctl:	The reset control to free.
60*4882a593Smuzhiyun 	 * @return 0 if OK, or a negative error code.
61*4882a593Smuzhiyun 	 */
62*4882a593Smuzhiyun 	int (*free)(struct reset_ctl *reset_ctl);
63*4882a593Smuzhiyun 	/**
64*4882a593Smuzhiyun 	 * rst_assert - Assert a reset signal.
65*4882a593Smuzhiyun 	 *
66*4882a593Smuzhiyun 	 * Note: This function is named rst_assert not assert to avoid
67*4882a593Smuzhiyun 	 * conflicting with global macro assert().
68*4882a593Smuzhiyun 	 *
69*4882a593Smuzhiyun 	 * @reset_ctl:	The reset signal to assert.
70*4882a593Smuzhiyun 	 * @return 0 if OK, or a negative error code.
71*4882a593Smuzhiyun 	 */
72*4882a593Smuzhiyun 	int (*rst_assert)(struct reset_ctl *reset_ctl);
73*4882a593Smuzhiyun 	/**
74*4882a593Smuzhiyun 	 * rst_deassert - Deassert a reset signal.
75*4882a593Smuzhiyun 	 *
76*4882a593Smuzhiyun 	 * @reset_ctl:	The reset signal to deassert.
77*4882a593Smuzhiyun 	 * @return 0 if OK, or a negative error code.
78*4882a593Smuzhiyun 	 */
79*4882a593Smuzhiyun 	int (*rst_deassert)(struct reset_ctl *reset_ctl);
80*4882a593Smuzhiyun };
81*4882a593Smuzhiyun 
82*4882a593Smuzhiyun #endif
83