[alsa-devel] [PATCH] ALSA - Replace msleep() with usleep_range() to save module loading time

[Wang Xingchao]

msleep(1) is not so accurate and may cause almost 15ms delay in azx_reset().
usleep_range() can reduce ~30ms loading time for Intel Haswell which has two HDA
controllers.

Signed-off-by: Wang Xingchao <wangxingchao2011 at gmail.com>
---
 sound/pci/hda/hda_intel.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index eb48109..865df90 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -1075,22 +1075,22 @@ static int azx_reset(struct azx *chip, int full_reset)
 
 	count = 50;
 	while (azx_readb(chip, GCTL) && --count)
-		msleep(1);
+		usleep_range(1000, 1500);
 
 	/* delay for >= 100us for codec PLL to settle per spec
 	 * Rev 0.9 section 5.5.1
 	 */
-	msleep(1);
+	usleep_range(1000, 1500);
 
 	/* Bring controller out of reset */
 	azx_writeb(chip, GCTL, azx_readb(chip, GCTL) | ICH6_GCTL_RESET);
 
 	count = 50;
 	while (!azx_readb(chip, GCTL) && --count)
-		msleep(1);
+		usleep_range(1000, 1500);
 
 	/* Brent Chartrand said to wait >= 540us for codecs to initialize */
-	msleep(1);
+	usleep_range(1000, 1500);
 
       __skip:
 	/* check to see if controller is ready */
-- 
1.7.9.5