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