1 /* SPDX-License-Identifier: GPL-2.0
2 *
3 * Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr>
4 */
5
6 #ifndef AC97_CONTROLLER_H
7 #define AC97_CONTROLLER_H
8
9 #include <linux/device.h>
10 #include <linux/list.h>
11
12 #define AC97_BUS_MAX_CODECS 4
13 #define AC97_SLOTS_AVAILABLE_ALL 0xf
14
15 struct ac97_controller_ops;
16
17 /**
18 * struct ac97_controller - The AC97 controller of the AC-Link
19 * @ops: the AC97 operations.
20 * @controllers: linked list of all existing controllers.
21 * @adap: the shell device ac97-%d, ie. ac97 adapter
22 * @nr: the number of the shell device
23 * @slots_available: the mask of accessible/scanable codecs.
24 * @parent: the device providing the AC97 controller.
25 * @codecs: the 4 possible AC97 codecs (NULL if none found).
26 * @codecs_pdata: platform_data for each codec (NULL if no pdata).
27 *
28 * This structure is internal to AC97 bus, and should not be used by the
29 * controllers themselves, excepting for using @dev.
30 */
31 struct ac97_controller {
32 const struct ac97_controller_ops *ops;
33 struct list_head controllers;
34 struct device adap;
35 int nr;
36 unsigned short slots_available;
37 struct device *parent;
38 struct ac97_codec_device *codecs[AC97_BUS_MAX_CODECS];
39 void *codecs_pdata[AC97_BUS_MAX_CODECS];
40 };
41
42 /**
43 * struct ac97_controller_ops - The AC97 operations
44 * @reset: Cold reset of the AC97 AC-Link.
45 * @warm_reset: Warm reset of the AC97 AC-Link.
46 * @read: Read of a single AC97 register.
47 * Returns the register value or a negative error code.
48 * @write: Write of a single AC97 register.
49 *
50 * These are the basic operation an AC97 controller must provide for an AC97
51 * access functions. Amongst these, all but the last 2 are mandatory.
52 * The slot number is also known as the AC97 codec number, between 0 and 3.
53 */
54 struct ac97_controller_ops {
55 void (*reset)(struct ac97_controller *adrv);
56 void (*warm_reset)(struct ac97_controller *adrv);
57 int (*write)(struct ac97_controller *adrv, int slot,
58 unsigned short reg, unsigned short val);
59 int (*read)(struct ac97_controller *adrv, int slot, unsigned short reg);
60 };
61
62 #if IS_ENABLED(CONFIG_AC97_BUS_NEW)
63 struct ac97_controller *snd_ac97_controller_register(
64 const struct ac97_controller_ops *ops, struct device *dev,
65 unsigned short slots_available, void **codecs_pdata);
66 void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl);
67 #else
68 static inline struct ac97_controller *
snd_ac97_controller_register(const struct ac97_controller_ops * ops,struct device * dev,unsigned short slots_available,void ** codecs_pdata)69 snd_ac97_controller_register(const struct ac97_controller_ops *ops,
70 struct device *dev,
71 unsigned short slots_available,
72 void **codecs_pdata)
73 {
74 return ERR_PTR(-ENODEV);
75 }
76
77 static inline void
snd_ac97_controller_unregister(struct ac97_controller * ac97_ctrl)78 snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl)
79 {
80 }
81 #endif
82
83 #endif
84