From 3f8c0df43dec51fbdfb2627f7574aa00a5fce98c Mon Sep 17 00:00:00 2001 From: Arjan Opmeer Date: Sat, 18 Apr 2009 19:05:40 -0700 Subject: Input: elantech - provide a workaround for jumpy cursor on firmware 2.34 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) (limited to 'drivers/input/mouse/elantech.c') 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; -- cgit v1.2.2 From b2546df69b6bef19513112fd54ffb5d37cb3eb7a Mon Sep 17 00:00:00 2001 From: Arjan Opmeer Date: Sat, 18 Apr 2009 19:10:17 -0700 Subject: Input: elantech - make sure touchpad is really in absolute mode There exist laptops with Elantech touchpads where switching to absolute mode does not happen, although writing the configuration register succeeds without error. Reading back the register afterwards reveils that the absolute mode bit is not set as if masked out by the touchpad firmware. Always read back register 0x10, make sure that for hardware version 1 the absolute mode bit is actually set and fail otherwise. This prevents the case where the touchpad is claimed by the Elantech driver but is nonetheless not working. Signed-off-by: Arjan Opmeer Signed-off-by: Dmitry Torokhov --- drivers/input/mouse/elantech.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'drivers/input/mouse/elantech.c') diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c index d3b591673792..4bc78892ba91 100644 --- a/drivers/input/mouse/elantech.c +++ b/drivers/input/mouse/elantech.c @@ -375,9 +375,14 @@ static int elantech_set_absolute_mode(struct psmouse *psmouse) rc = -1; break; } + } + + if (rc == 0) { /* - * Read back reg 0x10. The touchpad is probably initalising - * and not ready until we read back the value we just wrote. + * Read back reg 0x10. For hardware version 1 we must make + * sure the absolute mode bit is set. For hardware version 2 + * the touchpad is probably initalising and not ready until + * we read back the value we just wrote. */ do { rc = elantech_read_reg(psmouse, 0x10, &val); @@ -385,12 +390,18 @@ static int elantech_set_absolute_mode(struct psmouse *psmouse) break; tries--; elantech_debug("elantech.c: retrying read (%d).\n", - tries); + tries); msleep(ETP_READ_BACK_DELAY); } while (tries > 0); - if (rc) + + if (rc) { pr_err("elantech.c: failed to read back register 0x10.\n"); - break; + } else if (etd->hw_version == 1 && + !(val & ETP_R10_ABSOLUTE_MODE)) { + pr_err("elantech.c: touchpad refuses " + "to switch to absolute mode.\n"); + rc = -1; + } } if (rc) -- cgit v1.2.2