Letux Kernel

Issue 472: Missing some power management functions

Reported by Nikolaus Schaller, Jul 31, 2013

To me it seems that 3.11 is missing some power management functions. 
I have ~50mA during suspend. It's good start but not really usable 
now.
 
Regards
 
Radek

Comment 1 by Nikolaus Schaller, Sep 25, 2013

We should check:

TV output unused
When the TV output is not required then the following configuration 
should be implemented in order to reduce the power consumption to 
its minimum value.
The analog pins tv_ref, vssadac, vdda_dac, tv_out1/2 and tv_vfb1/2 
should be grounded. To avoid internal current leakage, the following 
bits must be set to 0:
DSS.DSS_CONTROL[5]
DAC_POWERDN_BGZ
DSS.VENC_OUTPUT_CONTROL[2:0]
PRCM.CM_FCLKEN_DSS[2]
EN_TV
CONTROL.CONTROL_DEVCONF[18]
TVOUTBYPASS

Comment 2 by Nikolaus Schaller, Oct 1, 2013

Status: Accepted
Owner: hns

Comment 3 by Nikolaus Schaller, Oct 11, 2013

We have to verify if the LCD panel goes to deep sleep in suspend, 
i.e. the panel driver is correct.
Otherwise the backlight may just be off but the panel will still 
draw some mA from the 3.3V rail.
This can easily be tested by suspending a device with and one 
without connected display.

Created: 8 years 3 months ago by Nikolaus Schaller

Updated: 8 years 1 month ago

Status: Accepted

Owner: Nikolaus Schaller

Labels:
Type:Defect
Priority:Critical
Milestone:3.10

This issue is related to
512 - Sus... may not work completely
707 - GTA...sumption still too high!