ALSA: ac97: Constify snd_ac97_bus_ops definitions

Now snd_ac97_bus() takes the const ops pointer, so we can define the
snd_ac97_bus_ops locally as const as well for further optimization.

There should be no functional changes by this patch.

Link: https://lore.kernel.org/r/20200103081714.9560-24-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

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

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 #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: ac97: fix device initialization in the compat layer

ac97->dev is an object of 'struct device' type. It should be initialized
via device_initialize() or device_register().

Fixes: 74426fbff66e ("ALSA: ac97: add an ac97 bus")
Signed-off-by: Lihua Yao <ylhuajnu@163.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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>