Gamecon driver fails to build on Kernel 4.19.x

Darksavior

@mitu I decided to use the latest weekly retropie-4.4.8-rpi2_rpi3.img.gz from May 26 and I can't reproduce the problem. No idea why the kernel was updated on my main build. The driver still doesn't build on the weekly, though.

System: Linux retropie 4.19.42-v7+ #1219 SMP Tue May 14 21:20:58 BST 2019 armv7l GNU/Linux
Loading new gamecon_gpio_rpi-1.3 DKMS files...
It is likely that 4.19.42-v7+ belongs to a chroot's host
Building for 4.19.42+ and 4.19.42-v7+
Building for architecture armv7l
Building initial module for 4.19.42+
Error! Bad return status for module build on kernel: 4.19.42+ (armv7l)
Consult /var/lib/dkms/gamecon_gpio_rpi/1.3/build/make.log for more information.

make.log

DKMS make.log for gamecon_gpio_rpi-1.3 for kernel 4.19.42+ (armv7l)
Mon 27 May 12:18:38 BST 2019
make -C /lib/modules/4.19.42+/build M=/var/lib/dkms/gamecon_gpio_rpi/1.3/build modules
make[1]: Entering directory '/usr/src/linux-headers-4.19.42+'
  CC [M]  /var/lib/dkms/gamecon_gpio_rpi/1.3/build/gamecon_gpio_rpi.o
/var/lib/dkms/gamecon_gpio_rpi/1.3/build/gamecon_gpio_rpi.c: In function ‘gc_probe’:
/var/lib/dkms/gamecon_gpio_rpi/1.3/build/gamecon_gpio_rpi.c:1138:2: error: implicit declaration of function ‘setup_timer’ [-Werror=implicit-function-declaration]
  setup_timer(&gc->timer, gc_timer, (long) gc);
  ^~~~~~~~~~~
cc1: some warnings being treated as errors
scripts/Makefile.build:309: recipe for target '/var/lib/dkms/gamecon_gpio_rpi/1.3/build/gamecon_gpio_rpi.o' failed
make[2]: *** [/var/lib/dkms/gamecon_gpio_rpi/1.3/build/gamecon_gpio_rpi.o] Error 1
Makefile:1524: recipe for target '_module_/var/lib/dkms/gamecon_gpio_rpi/1.3/build' failed
make[1]: *** [_module_/var/lib/dkms/gamecon_gpio_rpi/1.3/build] Error 2
make[1]: Leaving directory '/usr/src/linux-headers-4.19.42+'
Makefile:5: recipe for target 'all' failed
make: *** [all] Error 2

mitu

@Darksavior So it seems it's not building with 4.19.x, that's a real issue.

Darksavior

@mitu I updated the topic to the real problem.

BuZz

You will have to downgrade your kernel for now - https://retropie.org.uk/forum/post/190436

BuZz

@Darksavior Topic isn't correct (says 4.4) - it fails to build on 4.19.x - I'll sort it.

mitu

Looks like the change that breaks the driver is in 4.15, when setup_timer was replaced by timer_setup in the Linux kernel internal API (https://kernel.googlesource.com/pub/scm/linux/kernel/git/kees/linux/+/for-linus-timers-conversion-final-v4.15-rc1, https://lwn.net/Articles/735887/).

BuZz

@mitu Ah. Nice work. Should be an easy IFDEF fix then. No way I know of though of contacting author (maybe email in package info?), but worst case we could fix this ourselves.

This would be better on a GitHub repo also imho. Maybe they would upload their unpackaged files if they don't already have a repository somewhere (if we can contact them).

Darksavior

@BuZz The developer "marqs" sometimes posts on the raspberry pi forums. https://www.raspberrypi.org/forums/viewtopic.php?t=15787

This is his github repo: https://github.com/marqs85/

BuZz

@Darksavior thanks! :-)

mitu

@Darksavior If you're willing to try a patched version (since I have don't have the hardware setup), you can clone from my fork and give it try with the new 4.19.x kernel.

# clone & setup
git clone https://github.com/cmitu/gamecon_gpio_rpi
cd gamecon_gpio_rpi
sudo cp -r gamecon_gpio_rpi-1.3/ /usr/src/

# build the kernel
sudo dkms add gamecon_gpio_rpi/1.3
sudo dkms build gamecon_gpio_rpi/1.3
sudo dkms install gamecon_gpio_rpi/1.3

Darksavior

@mitu This works. Thanks! Thought I had to wait a few months like the last time the driver broke.

mitu

@Darksavior Alright, thanks for testing and reporting.
I'll submit the patches upstream - the repo(s) you indicated, maybe we should change also the scriptmodule to pull the sources from there.

mitu

@Darksavior The changes have been pushed upstream and also added to the RetroPie's package. If you want, you can update your RetroPie-setup script and then re-install the gamecon driver package to see if it works.

Darksavior

@mitu Gamecon driver no longer working when using the retropie fkms_rpi4 branch on a pi4. Might be too early for support. I'm asking before I go making a new topic or if it's ok in here.

mitu

@Darksavior Is the compilation not working or the module loads but the controller doesn't work ?

Darksavior

@mitu This time it's different. It seems to compile fine? ES sees both pads and gives me the option to configure them but they won't work. Jstest also sees both pads but no response. Not sure how to check if the module is loaded properly.
https://pastebin.com/fZXz6E7F

mitu

@Darksavior Yes, looks different than on a Pi3. The fact that pads are seen by ES and jstest seems to indicate that the driver is loaded, but you can also check with

lsmod | grep gamecon_gpio_rpi

Since this is the same Linux kernel version as on Stretch - 4.19, when you reported the issue - I think the problem is with either the GPIO configuration or the module compatibility with to the new PI model.

Darksavior

@mitu I ran that command and got 45056 0
At first I thought the controller ports weren't properly connected or maybe something desoldered, but it works fine on a pi3.

mitu

The module is loaded alright, I think is just not compatible with the RPI4 model.
I've looked at the bcm2835 GPIO library and - at the very least - the BCM2708_PERI_BASE is different on the PI4.
I can add a patch if you'd like to test - do you have the possibility to test on both RPI3/RPI4 models ?

Darksavior

@mitu Yes. I soldered an snes controller connector to an old ide cable so I can easily remove it and test on a pi3 or pi4.
On the pi3, would you like me to test with the latest retropie stretch weekly or use raspbian lite buster with the pi4 branch?