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ALSA: ad1889: Replace mdelay with usleep_range in snd_ad1889_ac97_ready

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snd_ad1889_ac97_ready() is never called in atomic context.

The call chain ending up at snd_ad1889_ac97_ready() is:
[1] snd_ad1889_ac97_ready() <- snd_ad1889_ac97_xinit() <-
	snd_ad1889_ac97_init() <- snd_ad1889_probe()

snd_ad1889_probe() is only set as ".probe" in struct pci_driver.
This function is not called in atomic context.

Despite never getting called from atomic context, snd_ad1889_ac97_ready()
calls mdelay for busy wait.
This is not necessary and can be replaced with usleep_range to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Jia-Ju Bai 2018-04-09 21:03:38 +08:00 committed by Takashi Iwai
parent 621fdf60ab
commit 1fa350b6e1
1 changed files with 1 additions and 1 deletions
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2
sound/pci/ad1889.c
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@ -258,7 +258,7 @@ snd_ad1889_ac97_ready(struct snd_ad1889 *chip)
while (!(ad1889_readw(chip, AD_AC97_ACIC) & AD_AC97_ACIC_ACRDY)
&& --retry)
mdelay(1);
usleep_range(1000, 2000);
if (!retry) {
dev_err(chip->card->dev, "[%s] Link is not ready.\n",
__func__);