[commit] r3502 - cpu/arm/olpc

[repository service]

Author: quozl
Date: Fri Dec 28 09:14:36 2012
New Revision: 3502
URL: http://tracker.coreboot.org/trac/openfirmware/changeset/3502

Log:
OLPC XO-4 - fix support for non-touchscreen SKUs, compatible with touchscreen SKUs, treats TOUCH_HD# signal as active high, since the touchscreen controller is pulling the signal low in normal operation, momentarily enables a pull-down in conflict against the permanent pull-up, in order to sample the signal properly.  Requires a BOM change.  #12391

Modified:
   cpu/arm/olpc/nn-touchscreen.fth

Modified: cpu/arm/olpc/nn-touchscreen.fth
==============================================================================
--- cpu/arm/olpc/nn-touchscreen.fth	Tue Dec 18 06:58:54 2012	(r3501)
+++ cpu/arm/olpc/nn-touchscreen.fth	Fri Dec 28 09:14:36 2012	(r3502)
@@ -70,7 +70,12 @@
 : reset  ( -- )  touch-rst-gpio# dup gpio-clr gpio-set  d# 250 ms  ;
 : hold-reset  ( -- )  touch-rst-gpio# gpio-clr  ;
 : no-data?  ( -- no-data? )  touch-int-gpio# gpio-pin@  ;
-: absent?  ( -- flag )  touch-hd-gpio# gpio-pin@  0=  ;
+: absent?  ( -- flag )
+   touch-hd-gpio# af@  +pull-dn  touch-hd-gpio# af!
+   1 ms
+   touch-hd-gpio# gpio-pin@
+   touch-hd-gpio# af@  0 +pull-dn invert and  touch-hd-gpio# af!
+;

d# 250 constant /pbuf
 0 value pbuf