On Wed, May 01, 2024 at 02:02:32PM +0000, Jonathan Denose wrote:
> 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>
Adding a couple more folks to take a look at this...
> ---
>
> 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
>
--
Dmitry
