On Fri, 5 Sep 2014, Benjamin Tissoires wrote: > In the Dell XPS 13 9333, it appears that sometimes the bus get confused > and corrupts the incoming data. It fills the input report with the > sentinel value "ff". Synaptics told us that such behavior does not comes > from the touchpad itself, so we filter out such reports here. > > Unfortunately, we can not simply discard the incoming data because they > may contain useful information. Most of the time, the misbehavior is > quite near the end of the report, so we can still use the valid part of > it. > > Fixes: > https://bugzilla.redhat.com/show_bug.cgi?id=1123584 > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> > --- > drivers/hid/hid-rmi.c | 31 ++++++++++++++++++++++++++----- > 1 file changed, 26 insertions(+), 5 deletions(-) > > diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c > index 8389e81..db92c3b 100644 > --- a/drivers/hid/hid-rmi.c > +++ b/drivers/hid/hid-rmi.c > @@ -320,9 +320,6 @@ static int rmi_f11_input_event(struct hid_device *hdev, u8 irq, u8 *data, > int offset; > int i; > > - if (size < hdata->f11.report_size) > - return 0; > - > if (!(irq & hdata->f11.irq_mask)) > return 0; > > @@ -332,9 +329,13 @@ static int rmi_f11_input_event(struct hid_device *hdev, u8 irq, u8 *data, > int fs_bit_position = (i & 0x3) << 1; > int finger_state = (data[fs_byte_position] >> fs_bit_position) & > 0x03; > + int position = offset + 5 * i; > + > + if (position + 5 > size) > + /* partial report, go on with what we received */ > + break; Do you perhaps want to warn the user here, so that he knows that things are getting a little bit hairy? Or is this happening so often that it makes no sense to warn about it? -- Jiri Kosina SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
