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diff --git a/src/udev/src/keymap/README.keymap.txt b/src/udev/src/keymap/README.keymap.txt new file mode 100644 index 0000000000..52d50ed2de --- /dev/null +++ b/src/udev/src/keymap/README.keymap.txt @@ -0,0 +1,101 @@ += The udev keymap tool = + +== Introduction == + +This udev extension configures computer model specific key mappings. This is +particularly necessary for the non-standard extra keys found on many laptops, +such as "brightness up", "next song", "www browser", or "suspend". Often these +are accessed with the Fn key. + +Every key produces a "scan code", which is highly vendor/model specific for the +nonstandard keys. This tool maintains mappings for these scan codes to standard +"key codes", which denote the "meaning" of the key. The key codes are defined +in /usr/include/linux/input.h. + +If some of your keys on your keyboard are not working at all, or produce the +wrong effect, then a very likely cause of this is that the scan code -> key +code mapping is incorrect on your computer. + +== Structure == + +udev-keymap consists of the following parts: + + keymaps/*:: mappings of scan codes to key code names + + 95-keymap.rules:: udev rules for mapping system vendor/product names and + input module names to one of the keymaps above + + keymap:: manipulate an evdev input device: + * write a key map file into a device (used by udev rules) + * dump current scan → key code mapping + * interactively display scan and key codes of pressed keys + + findkeyboards:: display evdev input devices which belong to actual keyboards, + i. e. those suitable for the keymap program + + fdi2rules.py:: convert hal keymap FDIs into udev rules and key map files + (Please note that this is far from perfect, since the mapping between fdi and + udev rules is not straightforward, and impossible in some cases.) + +== Fixing broken keys == + +In order to make a broken key work on your system and send it back to upstream +for inclusion you need to do the following steps: + + 1. Find the keyboard device. + + Run /usr/lib/udev/findkeyboards. This should always give you an "AT + keyboard" and possibly a "module". Some laptops (notably Thinkpads, Sonys, and + Acers) have multimedia/function keys on a separate input device instead of the + primary keyboard. The keyboard device should have a name like "input/event3". + In the following commands, the name will be written as "input/eventX" (replace + X with the appropriate number). + + 2. Find broken scan codes: + + sudo /usr/lib/udev/keymap -i input/eventX + + Press all multimedia/function keys and check if the key name that gets printed + out is plausible. If it is unknown or wrong, write down the scan code (looks + like "0x1E") and the intended functionality of this key. Look in + /usr/include/linux/input.h for an available KEY_XXXXX constant which most + closely approximates this functionality and write it down as the new key code. + + For example, you might press a key labeled "web browser" which currently + produces "unknown". Note down this: + + 0x1E www # Fn+F2 web browser + + Repeat that for all other keys. Write the resulting list into a file. Look at + /usr/lib/udev/keymaps/ for existing key map files and make sure that you use the + same structure. + + If the key only ever works once and then your keyboard (or the entire desktop) + gets stuck for a long time, then it is likely that the BIOS fails to send a + corresponding "key release" event after the key press event. Please note down + this case as well, as it can be worked around in + /usr/lib/udev/keymaps/95-keyboard-force-release.rules . + + 3. Find out your system vendor and product: + + cat /sys/class/dmi/id/sys_vendor + cat /sys/class/dmi/id/product_name + + 4. Generate a device dump with "udevadm info --export-db > /tmp/udev-db.txt". + + 6. Send the system vendor/product names, the key mapping from step 2, + and /tmp/udev-db.txt from step 4 to the linux-hotplug@vger.kernel.org mailing + list, so that they can be included in the next release. + +For local testing, copy your map file to /usr/lib/udev/keymaps/ with an appropriate +name, and add an appropriate udev rule to /usr/lib/udev/rules.d/95-keymap.rules: + + * If you selected an "AT keyboard", add the rule to the section after + 'LABEL="keyboard_vendorcheck"'. + + * If you selected a "module", add the rule to the top section where the + "ThinkPad Extra Buttons" are. + +== Author == + +keymap is written and maintained by Martin Pitt <martin.pitt@ubuntu.com>. |