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> --- Changes in v2: - change ps2_sendbyte() calls to ps2_command() 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..18f26315cae25 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_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_DISABLE); + + if (err) + psmouse_warn(psmouse, "Failed to deactivate mouse on %s: %d\n", + psmouse->ps2dev.serio->phys, err); + + err = ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE); + + 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.rc1.225.g2a3ae87e7f-goog