Missed keyboard events

[Bruce Webster]

Kernel - Linux raspberrypi 3.1.9+ #272 PREEMPT aug 7 2012

I am experiencing issues with key presses being correctly registered. I have tried two 5v adapters and 5v line is measured as 4.9V in one case and 5.05V in other. This problem was not apparent on the older Debian builds so it is unlikely a power/keyboard problem. it was apparent on the first rasbian build published on raspberrypi.org.

Symptoms are that key presses are either not registered or "key up" events are not captured resulting in repeat. Other USB devices appear to function correctly, eg mouse, usb drive. Problem is pressent in command line and in the GUI.

Keyboard is wired and works perfectly on other computers

[Dave Efflandt (efflandt)]

Not sure whether I should click affects me too, but I have the same symptoms with newer kernel and different hardware (Logitech di Novo Edge keyboard/mousepad using its 100 mA Logitech BT mini-receiver). Key presses and mouse taps or clicks frequently either do not register at all, or repeat until I hit same key or other key. That can cause browser windows to keep scrolling until I move mousepad cursor away from scrollbar. Sometimes I have to repeatedly click or tap on desktop launchers before they work (yes I know not to expect instant response). Cursor movement from mousepad seems fine, just taps, clicks or key presses that have a problem not happening or repeating. I selected that model from the keyboard list during initial RPi config on first boot.

Linux raspberrypi 3.2.27+ #250 PREEMPT Thu Oct 18 19:03:02 BST 2012 armv6l GNU/Linux

Newark 5.25 V 1 A power to 512 MB B RPi with only 100 mA Logitech BT mini-receiver on USB. Network is eth0 to tiny Netgear wireless bridge with its own 5 V 1 A power supply (not its alternate USB power cable). Just received the RPi yesterday and did "sudo apt-get update" and "sudo apt-get dist-upgrade" last night.

No key entry issues via ssh to RPi or when using wired 105 key US keyboard from a Dell, and Logitech laptop wireless mouse with its own tiny dongle on RPi USB ports. lsusb -v shows 98 mA for wireless mouse dongle plus 100 mA for Lite-On wired keyboard vs. 100 mA total for di Novo Edge wireless dongle. I did change /etc/default/keyboard from XKBMODEL="logidinovoedge" to XKBMODEL="pc105" before rebooting with the standard keyboard.

[Dave Efflandt (efflandt)]

Adding the following to the end of /boot/cmdline.txt seems to resolve dropped/sticky keys and dropped mousepad clicks for my wireless keyboard/mousepad, although, I hear that adding this may slow networking:

dwc_otg.speed=1

Note: everything in cmdline.txt should all be on one line.

[Bruce Webster (b-webster-08)]

I'll give that a go, but I believe that is for switching to usb 1.1 which isn't ideal. I've tried the arch distro as well and it has the same problems. I'm guessing this is a issue with the synopsis driver. Out of interest if anyone has a usb sniffer can you check the polling rate of the keyboard.
It makes little sense that this is happening though as presumably the cpu is easily fast enough to manage ~125Hz scan rates, even if the cpu was too slow to scan in the new value, it wouldn't stick on continuously. This would suggest that the HID driver is not being called often enough or is doing something wrong, but I'm guessing it would be called when the usb poll rescans the keyboard. The HID driver functions perfectly on everything else anyway.
I checked the synopsis driver for something stupid like a missing volatile declaration but it's there. I'm not great at trawling through makefiles unfortunately, might be worth checking the compile flags and verifying that volatile statements aren't being ignored

[peter green (plugwash)]

I'm marking this as invalid, we don't do significant kernel work in the raspbian project we leave that up to the raspberry pi foundation.

If you are still having problems please report it to the raspberry pi foundation on github.