[src/trunk]: src/sys/dev/usb add bug workaround for ELAN touchscreens

[macallan <macallan%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/ec4a0d3f0482
branches:  trunk
changeset: 822788:ec4a0d3f0482
user:      macallan <macallan%NetBSD.org@localhost>
date:      Thu Apr 06 20:06:44 2017 +0000

description:
add bug workaround for ELAN touchscreens

diffstat:

 sys/dev/usb/uts.c |  49 ++++++++++++++++++++++++++++++-------------------
 1 files changed, 30 insertions(+), 19 deletions(-)

diffs (79 lines):

diff -r bbb3fa919f2d -r ec4a0d3f0482 sys/dev/usb/uts.c
--- a/sys/dev/usb/uts.c Thu Apr 06 19:53:36 2017 +0000
+++ b/sys/dev/usb/uts.c Thu Apr 06 20:06:44 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uts.c,v 1.5 2016/04/27 19:35:17 jakllsch Exp $ */
+/*     $NetBSD: uts.c,v 1.6 2017/04/06 20:06:44 macallan Exp $ */
 
 /*
  * Copyright (c) 2012 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uts.c,v 1.5 2016/04/27 19:35:17 jakllsch Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uts.c,v 1.6 2017/04/06 20:06:44 macallan Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_usb.h"
@@ -205,9 +205,19 @@
        /* requires HID usage Digitizer:In_Range */
        if (!hid_locate(desc, size, HID_USAGE2(HUP_DIGITIZERS, HUD_IN_RANGE),
                uha->reportid, hid_input, &sc->sc_loc_z, &flags)) {
-               aprint_error_dev(sc->sc_hdev.sc_dev,
-                   "touchscreen has no range report\n");
-               return;
+               if (uha->uiaa->uiaa_vendor == USB_VENDOR_ELAN) {
+                       /*
+                        * XXX
+                        * ELAN touchscreens error out here but still return
+                        * valid data
+                        */
+                       aprint_debug_dev(sc->sc_hdev.sc_dev,
+                           "ELAN touchscreen found, workinmg around bug.\n");
+               } else {
+                       aprint_error_dev(sc->sc_hdev.sc_dev,
+                           "touchscreen has no range report\n");
+                       return;
+               }
        }
 
        /* multi-touch support would need HUD_CONTACTID and HUD_CONTACTMAX */
@@ -233,22 +243,23 @@
        sc->sc_calibcoords.maxy = 4095;
        sc->sc_calibcoords.samplelen = WSMOUSE_CALIBCOORDS_RESET;
        d = hid_start_parse(desc, size, hid_input);
-       while (hid_get_item(d, &item)) {
-               if (item.kind != hid_input
-                   || HID_GET_USAGE_PAGE(item.usage) != HUP_GENERIC_DESKTOP
-                   || item.report_ID != sc->sc_hdev.sc_report_id)
-                       continue;
-               if (HID_GET_USAGE(item.usage) == HUG_X) {
-                       sc->sc_calibcoords.minx = item.logical_minimum;
-                       sc->sc_calibcoords.maxx = item.logical_maximum;
+       if (d != NULL) {
+               while (hid_get_item(d, &item)) {
+                       if (item.kind != hid_input
+                           || HID_GET_USAGE_PAGE(item.usage) != HUP_GENERIC_DESKTOP
+                           || item.report_ID != sc->sc_hdev.sc_report_id)
+                               continue;
+                       if (HID_GET_USAGE(item.usage) == HUG_X) {
+                               sc->sc_calibcoords.minx = item.logical_minimum;
+                               sc->sc_calibcoords.maxx = item.logical_maximum;
+                       }
+                       if (HID_GET_USAGE(item.usage) == HUG_Y) {
+                               sc->sc_calibcoords.miny = item.logical_minimum;
+                               sc->sc_calibcoords.maxy = item.logical_maximum;
+                       }
                }
-               if (HID_GET_USAGE(item.usage) == HUG_Y) {
-                       sc->sc_calibcoords.miny = item.logical_minimum;
-                       sc->sc_calibcoords.maxy = item.logical_maximum;
-               }
+               hid_end_parse(d);
        }
-       hid_end_parse(d);
-
        tpcalib_init(&sc->sc_tpcalib);
        tpcalib_ioctl(&sc->sc_tpcalib, WSMOUSEIO_SCALIBCOORDS,
            (void *)&sc->sc_calibcoords, 0, 0);