linux/include/sound/ac97/codec.h
Greg Kroah-Hartman d69d804845 driver core: have match() callback in struct bus_type take a const *
In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *.  This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly.  This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-03 15:16:54 +02:00

114 lines
3.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0
*
* Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr>
*/
#ifndef __SOUND_AC97_CODEC2_H
#define __SOUND_AC97_CODEC2_H
#include <linux/device.h>
#define AC97_ID(vendor_id1, vendor_id2) \
((((vendor_id1) & 0xffff) << 16) | ((vendor_id2) & 0xffff))
#define AC97_DRIVER_ID(vendor_id1, vendor_id2, mask_id1, mask_id2, _data) \
{ .id = (((vendor_id1) & 0xffff) << 16) | ((vendor_id2) & 0xffff), \
.mask = (((mask_id1) & 0xffff) << 16) | ((mask_id2) & 0xffff), \
.data = (_data) }
struct ac97_controller;
struct clk;
/**
* struct ac97_id - matches a codec device and driver on an ac97 bus
* @id: The significant bits if the codec vendor ID1 and ID2
* @mask: Bitmask specifying which bits of the id field are significant when
* matching. A driver binds to a device when :
* ((vendorID1 << 8 | vendorID2) & (mask_id1 << 8 | mask_id2)) == id.
* @data: Private data used by the driver.
*/
struct ac97_id {
unsigned int id;
unsigned int mask;
void *data;
};
/**
* ac97_codec_device - a ac97 codec
* @dev: the core device
* @vendor_id: the vendor_id of the codec, as sensed on the AC-link
* @num: the codec number, 0 is primary, 1 is first slave, etc ...
* @clk: the clock BIT_CLK provided by the codec
* @ac97_ctrl: ac97 digital controller on the same AC-link
*
* This is the device instantiated for each codec living on a AC-link. There are
* normally 0 to 4 codec devices per AC-link, and all of them are controlled by
* an AC97 digital controller.
*/
struct ac97_codec_device {
struct device dev;
unsigned int vendor_id;
unsigned int num;
struct clk *clk;
struct ac97_controller *ac97_ctrl;
};
/**
* ac97_codec_driver - a ac97 codec driver
* @driver: the device driver structure
* @probe: the function called when a ac97_codec_device is matched
* @remove: the function called when the device is unbound/removed
* @shutdown: shutdown function (might be NULL)
* @id_table: ac97 vendor_id match table, { } member terminated
*/
struct ac97_codec_driver {
struct device_driver driver;
int (*probe)(struct ac97_codec_device *);
void (*remove)(struct ac97_codec_device *dev);
void (*shutdown)(struct ac97_codec_device *);
const struct ac97_id *id_table;
};
static inline struct ac97_codec_device *to_ac97_device(struct device *d)
{
return container_of(d, struct ac97_codec_device, dev);
}
#define to_ac97_driver(__drv) container_of_const(__drv, struct ac97_codec_driver, driver)
#if IS_ENABLED(CONFIG_AC97_BUS_NEW)
int snd_ac97_codec_driver_register(struct ac97_codec_driver *drv);
void snd_ac97_codec_driver_unregister(struct ac97_codec_driver *drv);
#else
static inline int
snd_ac97_codec_driver_register(struct ac97_codec_driver *drv)
{
return 0;
}
static inline void
snd_ac97_codec_driver_unregister(struct ac97_codec_driver *drv)
{
}
#endif
static inline struct device *
ac97_codec_dev2dev(struct ac97_codec_device *adev)
{
return &adev->dev;
}
static inline void *ac97_get_drvdata(struct ac97_codec_device *adev)
{
return dev_get_drvdata(ac97_codec_dev2dev(adev));
}
static inline void ac97_set_drvdata(struct ac97_codec_device *adev,
void *data)
{
dev_set_drvdata(ac97_codec_dev2dev(adev), data);
}
void *snd_ac97_codec_get_platdata(const struct ac97_codec_device *adev);
#endif