cregit-Linux how code gets into the kernel

Release 4.8 sound/ac97_bus.c

Directory: sound
 * Linux driver model AC97 bus interface
 * Author:      Nicolas Pitre
 * Created:     Jan 14, 2005
 * Copyright:   (C) MontaVista Software Inc.
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/string.h>
#include <sound/ac97_codec.h>

 * snd_ac97_check_id() - Reads and checks the vendor ID of the device
 * @ac97: The AC97 device to check
 * @id: The ID to compare to
 * @id_mask: Mask that is applied to the device ID before comparing to @id
 * If @id is 0 this function returns true if the read device vendor ID is
 * a valid ID. If @id is non 0 this functions returns true if @id
 * matches the read vendor ID. Otherwise the function returns false.

static bool snd_ac97_check_id(struct snd_ac97 *ac97, unsigned int id, unsigned int id_mask) { ac97->id = ac97->bus->ops->read(ac97, AC97_VENDOR_ID1) << 16; ac97->id |= ac97->bus->ops->read(ac97, AC97_VENDOR_ID2); if (ac97->id == 0x0 || ac97->id == 0xffffffff) return false; if (id != 0 && id != (ac97->id & id_mask)) return false; return true; }


lars-peter clausenlars-peter clausen94100.00%1100.00%

/** * snd_ac97_reset() - Reset AC'97 device * @ac97: The AC'97 device to reset * @try_warm: Try a warm reset first * @id: Expected device vendor ID * @id_mask: Mask that is applied to the device ID before comparing to @id * * This function resets the AC'97 device. If @try_warm is true the function * first performs a warm reset. If the warm reset is successful the function * returns 1. Otherwise or if @try_warm is false the function issues cold reset * followed by a warm reset. If this is successful the function returns 0, * otherwise a negative error code. If @id is 0 any valid device ID will be * accepted, otherwise only the ID that matches @id and @id_mask is accepted. */
int snd_ac97_reset(struct snd_ac97 *ac97, bool try_warm, unsigned int id, unsigned int id_mask) { struct snd_ac97_bus_ops *ops = ac97->bus->ops; if (try_warm && ops->warm_reset) { ops->warm_reset(ac97); if (snd_ac97_check_id(ac97, id, id_mask)) return 1; } if (ops->reset) ops->reset(ac97); if (ops->warm_reset) ops->warm_reset(ac97); if (snd_ac97_check_id(ac97, id, id_mask)) return 0; return -ENODEV; }


lars-peter clausenlars-peter clausen107100.00%1100.00%

EXPORT_SYMBOL_GPL(snd_ac97_reset); /* * Let drivers decide whether they want to support given codec from their * probe method. Drivers have direct access to the struct snd_ac97 * structure and may decide based on the id field amongst other things. */
static int ac97_bus_match(struct device *dev, struct device_driver *drv) { return 1; }


liam girdwoodliam girdwood1894.74%150.00%
nicolas pitrenicolas pitre15.26%150.00%

struct bus_type ac97_bus_type = { .name = "ac97", .match = ac97_bus_match, };
static int __init ac97_bus_init(void) { return bus_register(&ac97_bus_type); }


liam girdwoodliam girdwood16100.00%1100.00%

static void __exit ac97_bus_exit(void) { bus_unregister(&ac97_bus_type); }


liam girdwoodliam girdwood15100.00%1100.00%

module_exit(ac97_bus_exit); EXPORT_SYMBOL(ac97_bus_type); MODULE_LICENSE("GPL");

Overall Contributors

lars-peter clausenlars-peter clausen20967.20%228.57%
liam girdwoodliam girdwood9630.87%114.29%
mark brownmark brown30.96%114.29%
nicolas pitrenicolas pitre10.32%114.29%
jeffrin josejeffrin jose10.32%114.29%
jaroslav kyselajaroslav kysela10.32%114.29%
Directory: sound
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