diff options
Diffstat (limited to 'Documentation/input/devices/bcm5974.rst')
| -rw-r--r-- | Documentation/input/devices/bcm5974.rst | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/Documentation/input/devices/bcm5974.rst b/Documentation/input/devices/bcm5974.rst new file mode 100644 index 000000000000..4aca199b0aa6 --- /dev/null +++ b/Documentation/input/devices/bcm5974.rst @@ -0,0 +1,70 @@ +.. include:: <isonum.txt> + +------------------------ +BCM5974 Driver (bcm5974) +------------------------ + +:Copyright: |copy| 2008-2009 Henrik Rydberg <rydberg@euromail.se> + +The USB initialization and package decoding was made by Scott Shawcroft as +part of the touchd user-space driver project: + +:Copyright: |copy| 2008 Scott Shawcroft (scott.shawcroft@gmail.com) + +The BCM5974 driver is based on the appletouch driver: + +:Copyright: |copy| 2001-2004 Greg Kroah-Hartman (greg@kroah.com) +:Copyright: |copy| 2005 Johannes Berg (johannes@sipsolutions.net) +:Copyright: |copy| 2005 Stelian Pop (stelian@popies.net) +:Copyright: |copy| 2005 Frank Arnold (frank@scirocco-5v-turbo.de) +:Copyright: |copy| 2005 Peter Osterlund (petero2@telia.com) +:Copyright: |copy| 2005 Michael Hanselmann (linux-kernel@hansmi.ch) +:Copyright: |copy| 2006 Nicolas Boichat (nicolas@boichat.ch) + +This driver adds support for the multi-touch trackpad on the new Apple +Macbook Air and Macbook Pro laptops. It replaces the appletouch driver on +those computers, and integrates well with the synaptics driver of the Xorg +system. + +Known to work on Macbook Air, Macbook Pro Penryn and the new unibody +Macbook 5 and Macbook Pro 5. + +Usage +----- + +The driver loads automatically for the supported usb device ids, and +becomes available both as an event device (/dev/input/event*) and as a +mouse via the mousedev driver (/dev/input/mice). + +USB Race +-------- + +The Apple multi-touch trackpads report both mouse and keyboard events via +different interfaces of the same usb device. This creates a race condition +with the HID driver, which, if not told otherwise, will find the standard +HID mouse and keyboard, and claim the whole device. To remedy, the usb +product id must be listed in the mouse_ignore list of the hid driver. + +Debug output +------------ + +To ease the development for new hardware version, verbose packet output can +be switched on with the debug kernel module parameter. The range [1-9] +yields different levels of verbosity. Example (as root):: + + echo -n 9 > /sys/module/bcm5974/parameters/debug + + tail -f /var/log/debug + + echo -n 0 > /sys/module/bcm5974/parameters/debug + +Trivia +------ + +The driver was developed at the ubuntu forums in June 2008 [#f1]_, and now has +a more permanent home at bitmath.org [#f2]_. + +.. Links + +.. [#f1] http://ubuntuforums.org/showthread.php?t=840040 +.. [#f2] http://bitmath.org/code/ |