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[Guide] Patching LAPTOP DSDT/SSDTs

XPbIM3 said:
Hi!

I'am experiencing a DELL specific problem with my laptop
As You might know DELL laptops have a AC adapter check mechanism and if third-party adapter detected then battery forced to no charging and cpu forced on lowest P-state.

I have a N5050 with i5-2450M on third party AC adapter and trying to overcome a P-state limitations thru ACPI tables

Here is the quick info what i did:
-booting a High Sierra 10.13.6 with 4658 Clover
-tried to drop a variety of SSDT tables , up to full drop of all SSDT tables
-injected a ssdtPRGen generated SSDT instead of all tables
-removed all access to _PPC from DSDT, tried to do a force _PPC as Zero value in DSDT

Achieved a PerformanceStateArray visible in IOreg but got an MaxPowerState = 0x1 anyway and CPU on lowest P-state.
I thought a _PPC is a method to assign a MaxPowerState value, am I wrong?

Point me on what i should do to overcome P-state limitation, any ideas?

There is original ACPI tables in attachment and screenshot. If Someone will do a sneak peek on those tables and point me out on how AC adapter detection is implemented that would be awesome.
Click to expand...

You could use ACPIDebug to compare code path in the related ACPI code between genuine AC adapter and problematic 3rd party adapter.

But why would you want to use a inferior 3rd party adapter?
 
dloprios97 said:
Hi @RehabMan . I finished patching almost everything for my correct laptop functioning (still dealing with Brightness). I want to point out something. I used the Battery HP Envy17t patch over my HP 14 ac132la and its working flawlessly. No issues at all. You should add it to the notes of each patch.
Thank you so much.
Click to expand...

Thanks. Added.
 
RehabMan said:
But why would you want to use a inferior 3rd party adapter?
Click to expand...
Because i have no working Dell adapter at all. And it seems the hardware ID line in charging circuit is damaged.
 
XPbIM3 said:
Because i have no working Dell adapter at all. And it seems the hardware ID line in charging circuit is damaged.
Click to expand...

Simple/obvious solution: You might consider purchasing an official adapter from Dell or Ebay.
 
RehabMan said:
Simple/obvious solution: You might consider purchasing an official adapter from Dell or Ebay.
Click to expand...

I meant the ID circuit is damaged on laptop side. No matter what charger is plugged:eek:fficial or not - no valid ID received.
So thats the point - not to mess with hardware and workaround it with software ACPI path.


EDIT:

Decided to do i little dig into a hardware problem. Luckily there is a PDF schematics of this particualar DELL logic board.
So I've found a shot broken resistor on ID line on logic board, replaced it and my charger identification now working like a charm.
Now, theoretically we can figure out how this mechanism works on ACPI level comparing an ACPI state WITH and WITHOUT proper charger ID in system....but who cares.
And YES , now both script generated and clover generated p/c states leads to working speedstep.
 
Last edited:
my laptop specifications are as follows,
dell inspiron 14r 5437
intel i5-4200u
hd 4400 graphics
8gb ram
i can't fix my dsdt.dsl :/
i initially have 18 errors, and when i try to fix the first one, i get 36 instead, kindly help.
i have managed to get everything work, just need to patch my dsdt for better audio and backlight. Any help would be appreciated
 

Attachments

  • DSDT.dsl
    553.2 KB · Views: 125
arunim2000 said:
my laptop specifications are as follows,
dell inspiron 14r 5437
intel i5-4200u
hd 4400 graphics
8gb ram
i can't fix my dsdt.dsl :/
i initially have 18 errors, and when i try to fix the first one, i get 36 instead, kindly help.
i have managed to get everything work, just need to patch my dsdt for better audio and backlight. Any help would be appreciated
Click to expand...
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please read the faq for proper hardware profile setup:
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Hi RehabMan! I tried to follow your guide but I always end up with error on disassembly. Please help me with this.
 

Attachments

  • Origin.zip
    127 KB · Views: 67
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