LXR linux/sound/hda/hda_bus

   1/*
   2 * HD-audio bus
   3 */
   4#include <linux/init.h>
   5#include <linux/device.h>
   6#include <linux/module.h>
   7#include <linux/mod_devicetable.h>
   8#include <linux/export.h>
   9#include <sound/hdaudio.h>
  10
  11MODULE_DESCRIPTION("HD-audio bus");
  12MODULE_LICENSE("GPL");
  13
  14/**
  15 * hdac_get_device_id - gets the hdac device id entry
  16 * @hdev: HD-audio core device
  17 * @drv: HD-audio codec driver
  18 *
  19 * Compares the hdac device vendor_id and revision_id to the hdac_device
  20 * driver id_table and returns the matching device id entry.
  21 */
  22const struct hda_device_id *
  23hdac_get_device_id(struct hdac_device *hdev, struct hdac_driver *drv)
  24{
  25        if (drv->id_table) {
  26                const struct hda_device_id *id  = drv->id_table;
  27
  28                while (id->vendor_id) {
  29                        if (hdev->vendor_id == id->vendor_id &&
  30                                (!id->rev_id || id->rev_id == hdev->revision_id))
  31                                return id;
  32                        id++;
  33                }
  34        }
  35
  36        return NULL;
  37}
  38EXPORT_SYMBOL_GPL(hdac_get_device_id);
  39
  40static int hdac_codec_match(struct hdac_device *dev, struct hdac_driver *drv)
  41{
  42        if (hdac_get_device_id(dev, drv))
  43                return 1;
  44        else
  45                return 0;
  46}
  47
  48static int hda_bus_match(struct device *dev, struct device_driver *drv)
  49{
  50        struct hdac_device *hdev = dev_to_hdac_dev(dev);
  51        struct hdac_driver *hdrv = drv_to_hdac_driver(drv);
  52
  53        if (hdev->type != hdrv->type)
  54                return 0;
  55
  56        /*
  57         * if driver provided a match function use that otherwise we will
  58         * use hdac_codec_match function
  59         */
  60        if (hdrv->match)
  61                return hdrv->match(hdev, hdrv);
  62        else
  63                return hdac_codec_match(hdev, hdrv);
  64        return 1;
  65}
  66
  67static int hda_uevent(struct device *dev, struct kobj_uevent_env *env)
  68{
  69        char modalias[32];
  70
  71        snd_hdac_codec_modalias(dev_to_hdac_dev(dev), modalias,
  72                                sizeof(modalias));
  73        if (add_uevent_var(env, "MODALIAS=%s", modalias))
  74                return -ENOMEM;
  75        return 0;
  76}
  77
  78struct bus_type snd_hda_bus_type = {
  79        .name = "hdaudio",
  80        .match = hda_bus_match,
  81        .uevent = hda_uevent,
  82};
  83EXPORT_SYMBOL_GPL(snd_hda_bus_type);
  84
  85static int __init hda_bus_init(void)
  86{
  87        return bus_register(&snd_hda_bus_type);
  88}
  89
  90static void __exit hda_bus_exit(void)
  91{
  92        bus_unregister(&snd_hda_bus_type);
  93}
  94
  95subsys_initcall(hda_bus_init);
  96module_exit(hda_bus_exit);
  97