DSI-fix v2.2, no dss power domain suspend issue[update July 22]

DSI-fix v2 - get rid of DSI False Control Errors by optimization
DSI-fix v2 is a fixed version. With DSI-fix v1, Milestone A853 has dss power domain suspend issue, the phone can’t enter the suspend mode in some case while the phone is idle. With DSI-fix v2, the no suspend issue is gone.

This fix is created for CyanogenMod 7 for Milestone A853 (CM7), you can find the dsifix.ko file in /system/lib/module/. To use the DSI-fix v2, you should replace the existed dsifix.ko file with the new one by any root file explorer, remembered to set the file permissions to “rw-r-r-“, and reboot the phone.

If you are confused of it, just waiting for the new CM7 for Milestone A853 RC 12 final or RC 13 release.

PS. all the work is done by Nadlabak. Visit his homepage http://android.doshaska.net for more information.

A new DSI-fix module have been uploaded in this post, please check this out.
http://chromloop.com/?p=666

Old link: dsifix-v2.2
updated v2.2 on July 22.
please do not mirror 🙂

v2.2 changelog:use __builtin_return_address(0) to determine whether to suppress the BTA sync

v2.1 changelog: suppression of BTA send after framedone added.
test result: no DSI error occurred after 2 hours. It’s better than v2, though I don’t suffer for the DSI error before.

the information below is quote from Nadlabak’s Activity in github.com

don’t send the coordinates to panel before every frame if they haven’t
changed, as in such case they are already programmed

main change from previous version:
- no error recovery scheduling -> no dss power domain suspend issue
- DSS driver speed up (as we use manual update mode)
- errors should be prevented, not recovered afterwards

What is the DSI False Control error?
Motorola Milestone A853 official froyo(Android 2.2) kernel, version 2.6.32, has the DSI(Display Serial Interface) error bug, you can see those error message by running the dmesg command:

omapdss DSI error: rx fifo not empty when sending BTA, dumping data:
omapdss DSI error: ACK with ERROR (0x40):
omapdss DSI error: False Control Error
omapdss DSI error: rx fifo not empty when sending BTA, dumping data:
omapdss DSI error: ACK with ERROR (0x42):
omapdss DSI error: SoT Sync Error
omapdss DSI error: False Control Error
omapdss DSI error: rx fifo not empty when sending BTA, dumping data:
omapdss DSI error: ACK with ERROR (0x42):
omapdss DSI error: SoT Sync Error
omapdss DSI error: False Control Error

it usually make the phone display freeze, sometimes make the phone system reboot, it is caused by the occasionally kernel panic when the DSI error occurred.