HID: wacom: Handle failing HID_DG_CONTACTMAX requests
Hardware may not respond to a request for the HID_DG_CONTACTMAX feature and
we should be tolerant of such a failure. This is especially true when using
hid-replay where the hardware doesn't exist, but also for devices attached
to a flaky bus. This patch increases the number of allowable retries to
match other calls to 'wacom_get_report' and also provides a fallback which
forces 'touch_max = 16' (enough for any Wacom device seen so far).
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 109312f..eea18a6 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -125,9 +125,16 @@
break;
data[0] = field->report->id;
ret = wacom_get_report(hdev, HID_FEATURE_REPORT,
- data, 2, 0);
- if (ret == 2)
+ data, 2, WAC_CMD_RETRIES);
+ if (ret == 2) {
features->touch_max = data[1];
+ } else {
+ features->touch_max = 16;
+ hid_warn(hdev, "wacom_feature_mapping: "
+ "could not get HID_DG_CONTACTMAX, "
+ "defaulting to %d\n",
+ features->touch_max);
+ }
kfree(data);
}
break;