HID: logitech: read all 32 bits of report type bitfield
On big-endian systems (e.g., Apple PowerBook), trying to use a
logitech wireless mouse with the Logitech Unifying Receiver does not
work with v3.2 and later kernels. The device doesn't show up in
/dev/input. Older kernels work fine.
That is because the new hid-logitech-dj driver claims the device. The
device arrival notification appears:
20 00 41 02 00 00 00 00 00 00 00 00 00 00 00
and we read the report_types bitfield (02 00 00 00) to find out what
kind of device it is. Unfortunately the driver only reads the first 8
bits and treats that value as a 32-bit little-endian number, so on a
powerpc the report type seems to be 0x02000000 and is not recognized.
Even on little-endian machines, connecting a media center remote
control (report type 00 01 00 00) with this driver loaded would
presumably fail for the same reason.
Fix both problems by using get_unaligned_le32() to read all four
bytes, which is a little clearer anyway. After this change, the
wireless mouse works on Hugo's PowerBook again.
Based on a patch by Nestor Lopez Casado.
Addresses http://bugs.debian.org/671292
Reported-by: Hugo Osvaldo Barrera <hugo@osvaldobarrera.com.ar>
Inspired-by: Nestor Lopez Casado <nlopezcasad@logitech.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Nestor Lopez Casado <nlopezcasad@logitech.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
1 file changed