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[media] cx231xx: Fix power ramping issue

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On platforms that have CONFIG_HZ set to 100, the power ramp time effectively
ends up being 10ms.  However, on those that have a higher CONFIG_HZ, the time
ends up *actually* being 5ms, which doesn't allow enough time for the hardware
to be fully powered up before attempting to address it via i2c.

Change the constant to 10ms, which is long enough for the hardware to power
up, and won't really be anymore time than it was previously on platforms
with CONFIG_HZ being 100.

Credit goes to Mauro Carvalho Chehab and Gerd Hoffmann who previously
investigated this issue.

Tested with the Hauppauge USBLive 2, with which the problem was readily
reproducible after setting CONFIG_HZ to 1000.

Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Devin Heitmueller 2011-07-24 15:44:43 -03:00 committed by Mauro Carvalho Chehab
parent 992299e84a
commit 44ecf1df94
1 changed files with 1 additions and 1 deletions
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2
drivers/media/video/cx231xx/cx231xx.h
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@ -43,7 +43,7 @@
#include "cx231xx-conf-reg.h"
#define DRIVER_NAME "cx231xx"
#define PWR_SLEEP_INTERVAL 5
#define PWR_SLEEP_INTERVAL 10
/* I2C addresses for control block in Cx231xx */
#define AFE_DEVICE_ADDRESS 0x60