Current File : //usr/src/linux-headers-5.15.0-125-generic/include/sound/ac97/controller.h
/* SPDX-License-Identifier: GPL-2.0
*
* Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr>
*/
#ifndef AC97_CONTROLLER_H
#define AC97_CONTROLLER_H
#include <linux/device.h>
#include <linux/list.h>
#define AC97_BUS_MAX_CODECS 4
#define AC97_SLOTS_AVAILABLE_ALL 0xf
struct ac97_controller_ops;
/**
* struct ac97_controller - The AC97 controller of the AC-Link
* @ops: the AC97 operations.
* @controllers: linked list of all existing controllers.
* @adap: the shell device ac97-%d, ie. ac97 adapter
* @nr: the number of the shell device
* @slots_available: the mask of accessible/scanable codecs.
* @parent: the device providing the AC97 controller.
* @codecs: the 4 possible AC97 codecs (NULL if none found).
* @codecs_pdata: platform_data for each codec (NULL if no pdata).
*
* This structure is internal to AC97 bus, and should not be used by the
* controllers themselves, excepting for using @dev.
*/
struct ac97_controller {
const struct ac97_controller_ops *ops;
struct list_head controllers;
struct device adap;
int nr;
unsigned short slots_available;
struct device *parent;
struct ac97_codec_device *codecs[AC97_BUS_MAX_CODECS];
void *codecs_pdata[AC97_BUS_MAX_CODECS];
};
/**
* struct ac97_controller_ops - The AC97 operations
* @reset: Cold reset of the AC97 AC-Link.
* @warm_reset: Warm reset of the AC97 AC-Link.
* @read: Read of a single AC97 register.
* Returns the register value or a negative error code.
* @write: Write of a single AC97 register.
*
* These are the basic operation an AC97 controller must provide for an AC97
* access functions. Amongst these, all but the last 2 are mandatory.
* The slot number is also known as the AC97 codec number, between 0 and 3.
*/
struct ac97_controller_ops {
void (*reset)(struct ac97_controller *adrv);
void (*warm_reset)(struct ac97_controller *adrv);
int (*write)(struct ac97_controller *adrv, int slot,
unsigned short reg, unsigned short val);
int (*read)(struct ac97_controller *adrv, int slot, unsigned short reg);
};
#if IS_ENABLED(CONFIG_AC97_BUS_NEW)
struct ac97_controller *snd_ac97_controller_register(
const struct ac97_controller_ops *ops, struct device *dev,
unsigned short slots_available, void **codecs_pdata);
void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl);
#else
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)
{
return ERR_PTR(-ENODEV);
}
static inline void
snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl)
{
}
#endif
#endif
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