[media] cx231xx: Fix power ramping issue
authorDevin Heitmueller <dheitmueller@kernellabs.com>
Sun, 24 Jul 2011 18:44:43 +0000 (15:44 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Wed, 27 Jul 2011 20:56:04 +0000 (17:56 -0300)
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>
drivers/media/video/cx231xx/cx231xx.h

index c8d0d3dee798e420b137abe325a68c75683dc5c3..2000bc64c49784af168855f9dfab150b078a6d48 100644 (file)
@@ -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