hid: egalax: Report zero as minimum pressure

The firmware reports a logical minimum of one, but in order for
userspace applications to correctly map all reported values to
non-zero pressure, the driver needs to report a logical minimum of
zero.  Fixed with this patch.

Tested-by: Philipp Merkel <mail@philmerk.de>
Cc: Stephane Chatty <chatty@enac.fr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

diff --git a/drivers/hid/hid-egalax.c b/drivers/hid/hid-egalax.c
index 733bebc..aac8a63 100644 (file)
--- a/drivers/hid/hid-egalax.c
+++ b/drivers/hid/hid-egalax.c
@@ -90,6 +90,7 @@ static int egalax_input_mapping(struct hid_device *hdev, struct hid_input *hi,
                        set_abs(input, ABS_MT_TRACKING_ID, field, 0);
                        return 1;
                case HID_DG_TIPPRESSURE:
+                       field->logical_minimum = 0;
                        hid_map_usage(hi, usage, bit, max,
                                        EV_ABS, ABS_MT_PRESSURE);
                        set_abs(input, ABS_MT_PRESSURE, field, 0);