Input: elantech - discard the first 2 positions on some firmwares

commit 7f29f17b57255b6395046805a98bc663ded63fb8 upstream.

According to the Dell/Ubuntu driver, what was previously observed as
"jumpy cursor" corresponds to the hardware sending incorrect data for
the first two reports of a one touch finger. So let's use the same
workaround as in the other driver. Also, detect another firmware
version with the same behaviour, as in the other driver.

Signed-off-by: Éric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
[bwh: Adjust for 2.6.32]
[ak: adjust for 2.6.35]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index b18862b2a70e142a1e73bc306244ed3e377b438a..b188fd747c93d14c41e8b9390a3f1635ffd99f06 100644 (file)
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -185,7 +185,6 @@ 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 < 0x020000) {
                /*
@@ -203,11 +202,14 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
        }
 
        if (etd->jumpy_cursor) {
-               /* Discard packets that are likely to have bogus coordinates */
-               if (fingers > old_fingers) {
-                       elantech_debug("discarding packet\n");
-                       goto discard_packet_v1;
-               }
+               if (fingers != 1) {
+                       etd->single_finger_reports = 0;
+               } else if (etd->single_finger_reports < 2) {
+                       /* Discard first 2 reports of one finger, bogus */
+                       etd->single_finger_reports++;
+                       elantech_debug("elantech.c: discarding packet\n");
+                       return;
+               }
        }
 
        input_report_key(dev, BTN_TOUCH, fingers != 0);
@@ -238,9 +240,6 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
        }
 
        input_sync(dev);
-
- discard_packet_v1:
-       old_fingers = fingers;
 }
 
 /*
@@ -733,13 +732,14 @@ int elantech_init(struct psmouse *psmouse)
        etd->capabilities = param[0];
 
        /*
-        * This firmware seems to suffer from misreporting coordinates when
+        * This firmware suffers from misreporting coordinates when
         * a touch action starts causing the mouse cursor or scrolled page
         * to jump. Enable a workaround.
         */
-       if (etd->fw_version == 0x020022) {
-               pr_info("firmware version 2.0.34 detected, enabling jumpy cursor workaround\n");
-               etd->jumpy_cursor = 1;
+       if (etd->fw_version == 0x020022 || etd->fw_version == 0x020600) {
+               pr_info("elantech.c: firmware version 2.0.34/2.6.0 detected, "
+                       "enabling jumpy cursor workaround\n");
+               etd->jumpy_cursor = true;
        }
 
        if (elantech_set_absolute_mode(psmouse)) {

diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h
index ac57bde1bb9f3e62fb3b891227521f0b63df3946..aa4aac5d21983988e8e8de6c3d150d579dba0ae0 100644 (file)
--- a/drivers/input/mouse/elantech.h
+++ b/drivers/input/mouse/elantech.h
@@ -100,10 +100,11 @@ struct elantech_data {
        unsigned char reg_26;
        unsigned char debug;
        unsigned char capabilities;
-       unsigned char paritycheck;
-       unsigned char jumpy_cursor;
+       bool paritycheck;
+       bool jumpy_cursor;
        unsigned char hw_version;
-       unsigned int  fw_version;
+       unsigned int fw_version;
+       unsigned int single_finger_reports;
        unsigned char parity[256];
 };