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I am fairly technical and I was wondering if there are any software based hacks or modifications that I can apply to force the maximum of 2.1A to be supplied through a USB port without the attached device first negotiating this over the data pins?

By default my MacBook Pro (15" Mid 2015) will only supply 500mA through its USB ports if the device hasn't explicitly requested access to the additional 1600mA. This is mostly a software limitation I believe, because the hardware will be just fine with supplying 2.1A.

My question: Is it possible to make my MacBook Pro believe that the device has requested an additional 1600mA without the need of dongles or other external devices (which I don't have with me now, while I need the power for my phone at the moment). I'm ok with importing .kext files or doing other kind of low-level (read potentially risky) modifications.

EDIT: After some inspection of the MacBook's schematic the power isn't actually being limited, its my phone not willing to take more power because the macbook hasn't indicated yet that its alright to do so. Chargers do this by applying a special voltage to both the D- D+ data pins of the USB port, is there any chance this is possible in any other way? Otherwise I assume this is a lost cause and I should look into breaking protocol from my phone by just telling its alright to consume more current.

I changed the question title to better reflect newfound information

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    >"This is mostly a software limitation I believe, because the hardware will be just fine with supplying 2.1A." Source? – Scottmeup Jun 5 '18 at 9:20
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    Source is the macbook board schematic (820-00138 is used in this model), They power the USB ports from the PP5V_S4 line and its being limited by a TP2557DRB IC which is (As long as the system doesn't force it to be less) set to have a 2.2A power limit. Obviously can't share the direct schematic here but you can find it online – Bart Jun 5 '18 at 9:24
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    Do you have information that J4600 isn't responsible for the 500mA limit without assistance from the OS? I couldn't find detail on that part. – Scottmeup Jun 5 '18 at 10:01
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    J4600 can't limit as its simply a connector. The limiting is setup at U4600 over Pin 5 (USB_ILIM), The maximum is set over resistors R4600/01. However I'm starting to think the system is actually not able to limit the current passing through, since USB_ILIM_R is not connected to anything other then a testpoint. I think I should tell me phone to just pull more current, instead of telling my macbook this. Another option would be to have the macbook announce its a charger over the USB D- D+ pins, but that would probably be near impossible :) – Bart Jun 5 '18 at 10:07
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    I'm wondering if something upstream is just cutting off vbus when it senses some current over 500mA. As you mention USB_ILIM_R is just a testpoint, it appears that U4600 isn't involved in limiting the current below 2.1A. – Scottmeup Jun 5 '18 at 10:23

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