From 3f8c0df43dec51fbdfb2627f7574aa00a5fce98c Mon Sep 17 00:00:00 2001 From: Arjan Opmeer Date: Sat, 18 Apr 2009 19:05:40 -0700 Subject: [PATCH] Input: elantech - provide a workaround for jumpy cursor on firmware 2.34 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit It seems that Elantech touchpad firmware version 2.34 on the Hercules eCAFÉ suffers from a problem where bogus coordinates get reported at the beginning of a touch action. This causes the mouse cursor or the scrolled page to jump. Included patch provides a workaround that discards mouse packets that are likely to contain bogus coordinates. The workaround is activated when we detect touchpad with fimware version 2.34. Signed-off-by: Arjan Opmeer Signed-off-by: Dmitry Torokhov --- drivers/input/mouse/elantech.c | 27 +++++++++++++++++++++++++-- drivers/input/mouse/elantech.h | 5 +++-- 2 files changed, 28 insertions(+), 4 deletions(-) diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c index 6ab0eb1ada1c..d3b591673792 100644 --- a/drivers/input/mouse/elantech.c +++ b/drivers/input/mouse/elantech.c @@ -1,7 +1,7 @@ /* - * Elantech Touchpad driver (v5) + * Elantech Touchpad driver (v6) * - * Copyright (C) 2007-2008 Arjan Opmeer + * Copyright (C) 2007-2009 Arjan Opmeer * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published @@ -178,6 +178,7 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse) struct elantech_data *etd = psmouse->private; unsigned char *packet = psmouse->packet; int fingers; + static int old_fingers; if (etd->fw_version_maj == 0x01) { /* byte 0: D U p1 p2 1 p3 R L @@ -190,6 +191,14 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse) fingers = (packet[0] & 0xc0) >> 6; } + if (etd->jumpy_cursor) { + /* Discard packets that are likely to have bogus coordinates */ + if (fingers > old_fingers) { + elantech_debug("elantech.c: discarding packet\n"); + goto discard_packet_v1; + } + } + input_report_key(dev, BTN_TOUCH, fingers != 0); /* byte 2: x7 x6 x5 x4 x3 x2 x1 x0 @@ -216,6 +225,9 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse) } input_sync(dev); + + discard_packet_v1: + old_fingers = fingers; } /* @@ -662,6 +674,17 @@ int elantech_init(struct psmouse *psmouse) param[0], param[1], param[2]); etd->capabilities = param[0]; + /* + * This firmware seems to suffer from misreporting coordinates when + * a touch action starts causing the mouse cursor or scrolled page + * to jump. Enable a workaround. + */ + if (etd->fw_version_maj == 0x02 && etd->fw_version_min == 0x22) { + pr_info("elantech.c: firmware version 2.34 detected, " + "enabling jumpy cursor workaround\n"); + etd->jumpy_cursor = 1; + } + if (elantech_set_absolute_mode(psmouse)) { pr_err("elantech.c: failed to put touchpad into absolute mode.\n"); goto init_fail; diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h index bee282b540bc..ed848cc80814 100644 --- a/drivers/input/mouse/elantech.h +++ b/drivers/input/mouse/elantech.h @@ -1,7 +1,7 @@ /* - * Elantech Touchpad driver (v5) + * Elantech Touchpad driver (v6) * - * Copyright (C) 2007-2008 Arjan Opmeer + * Copyright (C) 2007-2009 Arjan Opmeer * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published @@ -104,6 +104,7 @@ struct elantech_data { unsigned char fw_version_min; unsigned char hw_version; unsigned char paritycheck; + unsigned char jumpy_cursor; unsigned char parity[256]; }; -- 2.20.1