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    SubjectRe: [PATCH 2.6.13.1 1/1] CS5535 AUDIO ALSA driver
    > > +static int __devinit snd_cs5535audio_probe(struct pci_dev *pci,
    > > + const struct pci_device_id *pci_id)
    > > +{
    > > + static int dev;
    > > + snd_card_t *card;
    > > + cs5535audio_t *cs5535au;
    > > + int err;
    > > +
    > > + if (dev >= SNDRV_CARDS)
    > > + return -ENODEV;
    > > + if (!enable[dev]) {
    > > + dev++;
    > > + return -ENOENT;
    > > + }
    > > +
    > > + card = snd_card_new(index[dev], id[dev], THIS_MODULE, 0);
    > > + if (card == NULL)
    > > + return -ENOMEM;
    > > +
    > > + if ((err = snd_cs5535audio_create(card, pci, &cs5535au)) < 0) {
    > > + snd_card_free(card);
    > > + return err;
    > > + }
    > > +
    > > + if ((err = snd_cs5535audio_mixer(cs5535au)) < 0) {
    > > + snd_card_free(card);
    > > + return err;
    > > + }
    > > +
    > > + if ((err = snd_cs5535audio_pcm(cs5535au)) < 0) {
    > > + snd_card_free(card);
    > > + return err;
    > > + }
    > > +
    > > + strcpy(card->driver, DRIVER_NAME);
    > > +
    > > + strcpy(card->shortname, "CS5535 Audio");
    > > + sprintf(card->longname, "%s %s at 0x%lx, irq %i",
    > > + card->shortname, card->driver,
    > > + cs5535au->port, cs5535au->irq);
    > > +
    > > + if ((err = snd_card_register(card)) < 0) {
    > > + snd_card_free(card);
    > > + return err;
    > > + }
    > > +
    > > + pci_set_drvdata(pci, card);
    > > + dev++;
    > > + return 0;
    > > +}
    >
    > Ditto.
    >
    > The handling of `dev' is racy ;)

    I took a quick look at the dev handling.

    % egrep -B20 "dev\+\+" $lintree/sound/pci/*.c
    <snip>
    --
    ../azt3328.c- return -ENODEV;
    ../azt3328.c- if (!enable[dev]) {
    ../azt3328.c: dev++;
    --
    ../azt3328.c-
    ../azt3328.c- pci_set_drvdata(pci, card);
    ../azt3328.c: dev++;
    --
    ../cmipci.c- return -ENODEV;
    ../cmipci.c- if (! enable[dev]) {
    ../cmipci.c: dev++;
    --
    ../cmipci.c- }
    ../cmipci.c- pci_set_drvdata(pci, card);
    ../cmipci.c: dev++;
    --
    <snip>

    So I think everyone is doing the same thing. I think probe is called
    from driver_probe_device through device_add and in this case that's
    from pci_bus_add_device/s from pci_do_scan_bus. I think the device
    probe functions are therefore called serially and there is no risk of
    a race condition. I hope that's right.

    Thanks,
    jk
    -
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