4.19-stable review patch. If anyone has any objections, please let me know.
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From: Jonathan Denose jdenose@google.com
[ Upstream commit a69ce592cbe0417664bc5a075205aa75c2ec1273 ]
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@google.com Link: https://lore.kernel.org/r/20240503155020.v2.1.Ifa0e25ebf968d8f307f58d6780369... Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/input/mouse/elantech.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+)
diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c index 6759cab82a723..6f747c59cd652 100644 --- a/drivers/input/mouse/elantech.c +++ b/drivers/input/mouse/elantech.c @@ -1527,16 +1527,47 @@ 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 */ static int elantech_reconnect(struct psmouse *psmouse) { + int err; + psmouse_reset(psmouse);
if (elantech_detect(psmouse, 0)) return -1;
+ if (dmi_check_system(elantech_needs_reenable)) { + 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");