1/*
 2 *  Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr>
 3 *
 4 * This program is free software; you can redistribute it and/or modify
 5 * it under the terms of the GNU General Public License version 2 as
 6 * published by the Free Software Foundation.
 7 */
 8#ifndef AC97_CONTROLLER_H
 9#define AC97_CONTROLLER_H
10
11#include <linux/device.h>
12#include <linux/list.h>
13
14#define AC97_BUS_MAX_CODECS 4
15#define AC97_SLOTS_AVAILABLE_ALL 0xf
16
17struct ac97_controller_ops;
18
19/**
20 * struct ac97_controller - The AC97 controller of the AC-Link
21 * @ops:		the AC97 operations.
22 * @controllers:	linked list of all existing controllers.
23 * @adap:		the shell device ac97-%d, ie. ac97 adapter
24 * @nr:			the number of the shell device
25 * @slots_available:	the mask of accessible/scanable codecs.
26 * @parent:		the device providing the AC97 controller.
27 * @codecs:		the 4 possible AC97 codecs (NULL if none found).
28 * @codecs_pdata:	platform_data for each codec (NULL if no pdata).
29 *
30 * This structure is internal to AC97 bus, and should not be used by the
31 * controllers themselves, excepting for using @dev.
32 */
33struct ac97_controller {
34	const struct ac97_controller_ops *ops;
35	struct list_head controllers;
36	struct device adap;
37	int nr;
38	unsigned short slots_available;
39	struct device *parent;
40	struct ac97_codec_device *codecs[AC97_BUS_MAX_CODECS];
41	void *codecs_pdata[AC97_BUS_MAX_CODECS];
42};
43
44/**
45 * struct ac97_controller_ops - The AC97 operations
46 * @reset:	Cold reset of the AC97 AC-Link.
47 * @warm_reset:	Warm reset of the AC97 AC-Link.
48 * @read:	Read of a single AC97 register.
49 *		Returns the register value or a negative error code.
50 * @write:	Write of a single AC97 register.
51 *
52 * These are the basic operation an AC97 controller must provide for an AC97
53 * access functions. Amongst these, all but the last 2 are mandatory.
54 * The slot number is also known as the AC97 codec number, between 0 and 3.
55 */
56struct ac97_controller_ops {
57	void (*reset)(struct ac97_controller *adrv);
58	void (*warm_reset)(struct ac97_controller *adrv);
59	int (*write)(struct ac97_controller *adrv, int slot,
60		     unsigned short reg, unsigned short val);
61	int (*read)(struct ac97_controller *adrv, int slot, unsigned short reg);
62};
63
64#if IS_ENABLED(CONFIG_AC97_BUS_NEW)
65struct ac97_controller *snd_ac97_controller_register(
66	const struct ac97_controller_ops *ops, struct device *dev,
67	unsigned short slots_available, void **codecs_pdata);
68void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl);
69#else
70static inline struct ac97_controller *
71snd_ac97_controller_register(const struct ac97_controller_ops *ops,
72			     struct device *dev,
73			     unsigned short slots_available,
74			     void **codecs_pdata)
75{
76	return ERR_PTR(-ENODEV);
77}
78
79static inline void
80snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl)
81{
82}
83#endif
84
85#endif