I've the same problem, I was trying to install a recovery image and it failed at the downloading PIT step.

I'm using ubuntu-14.04 LTS (fully patched) with my T-mobile note 4 (the original, not the newer T3 model). I get exactly the same error:
'''
Some devices may take up to 2 minutes to respond.
Please be patient!

Session begun.

Downloading device's PIT file...
ERROR: Failed to send request to end PIT file transfer!
ERROR: Failed to download PIT file!
Ending session...
ERROR: Failed to send end session packet!
Releasing device interface...
Re-attaching kernel driver...
'''

I tried compiling heimdall 1.4.1 from git, it was a bit tricky, but it fails in a very similar way:
'''
Initialising connection...
Detecting device...
Claiming interface...
Setting up interface...

Initialising protocol...
ERROR: Protocol initialisation failed!

Both are with my device in recovery mode saying:
ODIN MODE (HIGH SPEED)
PRODUCT NAME: SM-910T
...
Downloading...
Do not turn off target.
'''

Try heimdall 1.2,

It saved my galaxy s4 lte

From where? I found 1.4.0 here: https://bitbucket.org/benjamin_dobell/heimdall/downloads

v1.1.1, v1.3.0, v1.3.1, v1.3.2, v1.4.0, and v1.4.1 here:
https://github.com/Benjamin-Dobell/Heimdall/releases

Ah, hrm, I did find some ubuntu packages that claimed to be 1.2.0, but if I run them they claim they are 1.0.8. I tried 1.3.0, 1.4.0, and 1.4.1. None seem to work with my t-mobile note 4.

I dont know what happened to 1.2. But i remember it worked.Now I run Odin in a VM to use it, havent used heimdall in a while. Flashes recovery, ROM and it's Done.

Might be your kernel, too, heimdall seems not to like liquorix kernel 4.x

@yagomont The kernel having an impact seems unlikely. Heimdall communicates with the secondary bootloader. Depending on how you flashed your kernel perhaps you replaced the secondary bootloader at the same time.

@spikebike @yagomont Old releases (including 1.2) can be found here:
https://github.com/Benjamin-Dobell/Heimdall/downloads

Quite a lot has changed since then, I'd be a bit surprised if it worked with anything beyond an S3.

I am talking about the linux kernel in my computer.

I am talking about the linux kernel in my computer.

Whoops, sorry! That most certainly could lead to wildly different USB behaviour, libusb-1.0 seems to be a lot more finicky than I'd like.

Hey, you can always download the pit file for your phone in xda developers. Ser if that works.

@yagomont That will only work if you are repartitioning... and if Heimdall is having difficulty communicating with your device then I strongly advise against doing that.

@Benjamin-Dobell I installed heimdall_1.2.0_amd64.deb, but when I run it:
Heimdall v1.0.2b, Copyright (c) 2010-2011, Benjamin Dobell, Glass Echidna

I have a completely stock Note 4 and a collection of ubuntu-14.04 LTS desktops and laptops running a linux 3.13.0-30-lowlatency low latency kernel (the default). I tried all the versions I could find of heimdall and built a few from source as well. Any idea on what to try to get pit downloads to work?

I'm closing this issue as I'm pretty sure the problem is already resolved if you compile from master.

I know compiling is not ideal, I've opened #295

Hi, thanks much for this software,
Mac OSX (10.8.5) here.
Today I've compiled from master and tried downloading the SM-T533's pit file, but I stille get an error:

Initialising connection...
Detecting device...
Claiming interface...
Setting up interface...

Initialising protocol...
ERROR: Protocol initialisation failed!

Releasing device interface...

Any help would be appreciated

I can repro with code from master.

In my experience, moving from 1.4.1 to master 1.4.2 solved the problem

@Germano0 was right: it is solved in 1.4.2.

Especially for Debian users, see this comment to compile Heimdall, because 1.4.2 is not yet in the repositories.

@lebarde @Benjamin-Dobell , I feel like that comment should be integrated into the Linux readme, because I was stymied for hours trying to get it to compile on an Ubuntu based system because of that last command. Maybe later if need be I can throw together a PR for it

I had the same issue with a Galaxy S5 (SM-G900F) and Windows 7.
Compiling Heimdall 1.4.2 solved the problem.
But it was a disaster to get the make-process run successfully.

It seems, that the recent version of MSYS64 has changed in some behaviours (well, that's just my assumption, because I hadn't used msys64 before and there are differences to the readme, which was described as pretty good in some comments I read):

• There was no make.exe in msys64/mingw64/bin
• The mingw32-make.exe in msys64/mingw64/bin was not recognized resp. used
• The cmake command line option -DQt5Widgets_DIR had no effect
• The cmake command line option -G "MSYS Makefiles" had to be changed to -G "MinGW Makefiles"

I had no experience with make files before. Also this is only a memory log (memorandum/minutes from memory) of which actions resulted in progress. So there may be simpler solutions.

My solution was:
(1) Install MSYS2 64-bit (x86_64) to default directory: C:\msys64
On a Question something like: "2 versions of package xyz available: use abc or git?" I chose git-version (did not try the other version, so it may work too).

(2) Update package data base (like in the readme):
Pacman -Syu

(3) Install packages (like in the readme):
Pacman -S mingw-w64-x86_64 mingw-w64-x86_64-clang mingw-w64-x86_64-cmake mingw-w64-x86_64-libusb mingw-w64-x86_64-qt5-static make

(4) Install additional packages:
pacman -S mingw-w64-x86_64-libwebp mingw-w64-x86_64-jasper mingw-w64-x86_64-dbus
pacman -S mingw-w64-x86_64-gcc
Notes:

• I think the package mingw-w64-x86_64-gcc was already installed
• jasper was a missing dependency in the linking process. I don't know, if the others here are really needed
• There may be other additional packages which I forgot. If this is the case, it should be no problem to solve this with some research (Well, I Just don't want to do delete and repeat everything ;-)

(5) Go to directory [msys64-install-dir]/mingw64/bin/
If there is no make.exe:
Copy and rename mingw32-make.exe to make.exe

(6) Go the directory were the Heimdall sources are located (I used: c:\cbuilds\heimdall)
Open CMakeLists.txt and insert:
set (CMAKE_PREFIX_PATH "C:\\msys64\\mingw64\\qt5-static\\lib\\cmake\\Qt5Widgets")
Notes:

• The path to the msys64 directory may be adjusted.
• I don't know if it is relevant at which position this line is inserted. I inserted it right after the first one with cmake_minimum_required(VERSION 2.8.4)

(7) Open Terminal in the heimdall source directory:

mkdir build
cd build
cmake -G "MinGW Makefiles" -DCMAKE_BUILD_TYPE=Release ..
make

(8) The executable files are located in [heimdall-source-dir]/build/bin