diff options
author | Robert Jarzmik | 2017-09-02 21:54:04 +0200 |
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committer | Mark Brown | 2017-09-04 18:24:56 +0100 |
commit | 74426fbff66eea8e8d1f42c8238c268d1e63a832 (patch) | |
tree | 98b6d36b8fc9f8059cbbb2114ce592dab5a94be7 /include/sound/ac97/controller.h | |
parent | 8e4f7d9b8c652b4eb3ceb790e1e9fe433f9e3b58 (diff) |
ALSA: ac97: add an ac97 bus
AC97 is a bus for sound usage. It enables for a AC97 AC-Link to link one
controller to 0 to 4 AC97 codecs.
The goal of this new implementation is to implement a device/driver
model for AC97, with an automatic scan of the bus and automatic
discovery of AC97 codec devices.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'include/sound/ac97/controller.h')
-rw-r--r-- | include/sound/ac97/controller.h | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/include/sound/ac97/controller.h b/include/sound/ac97/controller.h new file mode 100644 index 000000000000..b36ecdd64f14 --- /dev/null +++ b/include/sound/ac97/controller.h @@ -0,0 +1,85 @@ +/* + * Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#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 |