[Galaxy Tab 10.1 Android Development] jaswinky:
Ok, here it is:

Firstly, comment that I confirmed that in standard and 1.2-1.5 kernels, when you plug to a USB port (laptop, desktop PC, or any non-samsung charger 0,5, 1 or 2A), the system detects it as non AC charger (USB charger) and the current is just 0,5A in all cases, so that you can maintain your charge without drain (only if you are not playing Asphalt 7, of course...), considering the drain in standby state with screen on is about 0,45-0,55A

In this first graph you can see the difference between screen on and no activity, sleep mode (screen turned off), and wake up... we can see that sleep mode drain is about 150mA, normal drain considering that min CPU freq is 216MHz... If any got to activate minor min freq, maybe the drain in sleep mode would fall a bit...

View attachment 1269975

Now, I'll put some graph, all with 1.5experimental (it is, 1.5 considering all USB power connections as AC, same as samsung oficial 2A charger). The USB tested chargers was, in this order (log in 5 seg interval):

1. Samsung AC charger,

2. 0,5A non-samsung wall charger

3. External travel battery 2A port

4. Same external travel battery 1A port

5. USB port laptop (Acer)

6. USB front port desktop PC

7. Car charger 2A port

8. Same car charger 1A port

The process was, in all cases, connect in screen on state, turn off the screen for a while, turn it back on, and unplug... so the maxime values correspond to a screen off state.

View attachment 1269976

You will see the current on each gadget (difference betwen previous state and connect state), in screen off mode (so I add to the max values 150mA):

1. Samsung AC charger: About 1,5A

2. 0,5A non-samsung wall charger: about 0,5A

3. External travel battery 2A port: about 1,5A

4. Same external travel battery 1A port: about 1,5A (As you see, I didn't give it enough time to get a value in screen off state, so I checked it again during the report)

5. USB port laptop (Acer): 1,15A

6. USB front port desktop PC: 0,5A

7. Car charger 2A port: 1,5A

8. Same car charger 1A port: 1,4A

You can see that with my two gadgets, the external battery and the car charger using the ports for 1A (smartphone port), the current is greater than 1A. You could think that it is dangerous for the gadget, and yes, you're right, but we should consider that both gadgets are internaly ready to give 2A, so in this case it should not be dangerous... The reason why it gives more than 1A in this 1A port is that the internal limit protection is at 2A... Anyway, when I use this, I'll use 2A ports, of course...

You can see as, even the tablet ask for 1,5A to 2A, if the device cannot give that cuurent, it will not do it, as USB PC desktop and 0,5 wall carger cases. You must also consider nowadays, the devices are all protected electronically, so if the gadget is only 10 years or less, it is high probbably it will be safe...

Conclusions:

If you have not gadgets as mines, external 2A battery or car charger for our tablet, or you are allow to spend money in a original samsung charger in case of damage of your actual charger, you don't need this mod in the kernel, you allways can maintain the battery connecting to the USB port in your PC and that's all... But if you have this gadgets, or you don't want to spend much money in a original samsung charger, you should need this mod (changes in acallways c code) in the kernel to consider all USB power connections as AC chargers and allow up to 2A charging, having a bit of care and that's all (really be care with chargers or USB PC ports with more than 5-7 years which could not have any internal current protection, but it is really very difficult to find nowadays a old AC-DC charger with USB port...).

Hope this report have been usefull for you.