The Lenovo N24 on resume becomes stuck in a state where it
sends incorrect packets, causing elantech_packet_check_v4 to fail.
The only way for the device to resume sending the correct packets is for
it to be disabled and then re-enabled.
This change adds a dmi check to trigger this behavior on resume.
Signed-off-by: Jonathan Denose <jdenose@xxxxxxxxxx>
---
drivers/input/mouse/elantech.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 4e38229404b4b..e0f3095b4227e 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -1476,6 +1476,23 @@ static void elantech_disconnect(struct psmouse *psmouse)
psmouse->private = NULL;
}
+/*
+ * Some hw_version 4 models fail to properly activate absolute mode on
+ * resume without going through disable/enable cycle.
+ */
+static const struct dmi_system_id elantech_needs_reenable[] = {
+#if defined(CONFIG_DMI) && defined(CONFIG_X86)
+ {
+ /* Lenovo N24 */
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "81AF"),
+ },
+ },
+#endif
+ { }
+};
+
/*
* Put the touchpad back into absolute mode when reconnecting
*/
@@ -1486,6 +1503,22 @@ static int elantech_reconnect(struct psmouse *psmouse)
if (elantech_detect(psmouse, 0))
return -1;
+ if (dmi_check_system(elantech_needs_reenable)) {
+ int err;
+
+ err = ps2_sendbyte(&psmouse->ps2dev, PSMOUSE_CMD_DISABLE, NULL);
+
+ if (err)
+ psmouse_warn(psmouse, "Failed to deactivate mouse on %s: %d\n",
+ psmouse->ps2dev.serio->phys, err);
+
+ err = ps2_sendbyte(&psmouse->ps2dev, PSMOUSE_CMD_ENABLE, NULL);
+
+ if (err)
+ psmouse_warn(psmouse, "Failed to reactivate mouse on %s: %d\n",
+ psmouse->ps2dev.serio->phys, err);
+ }
+
if (elantech_set_absolute_mode(psmouse)) {
psmouse_err(psmouse,
"failed to put touchpad back into absolute mode.\n");
--
2.45.0.rc0.197.gbae5840b3b-goog
