On Wed, Dec 12, 2018 at 04:42:05PM +0100, Benjamin Tissoires wrote:
> The current implementation of elan_i2c is known to not support those
> 2 laptops.
>
> A proper fix is to tweak both elantech and elan_i2c to transmit the
> correct information from PS/2, which would make a bad candidate for
> stable.
>
> So to give us some time for fixing the root of the problem, disable
> elan_i2c for the devices we know are not behaving properly.
>
> Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1803600
> Link: https://bugs.archlinux.org/task/59714
> Fixes: df077237cf55 Input: elantech - detect new ICs and setup Host Notify
> for them
>
> Cc: sta...@vger.kernel.org # v4.18+
> Signed-off-by: Benjamin Tissoires <benjamin.tissoi...@redhat.com>
Acked-by: Peter Hutterer <peter.hutte...@who-t.net>
Cheers,
Peter
> ---
> drivers/input/mouse/elantech.c | 18 ++++++++++++++++--
> 1 file changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
> index 2d95e8d93cc7..830ae9f07045 100644
> --- a/drivers/input/mouse/elantech.c
> +++ b/drivers/input/mouse/elantech.c
> @@ -1767,6 +1767,18 @@ static int elantech_smbus =
> IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) ?
> module_param_named(elantech_smbus, elantech_smbus, int, 0644);
> MODULE_PARM_DESC(elantech_smbus, "Use a secondary bus for the Elantech
> device.");
>
> +static const char * const i2c_blacklist_pnp_ids[] = {
> + /*
> + * these are known to not be working properly as bits are missing
> + * in elan_i2c
> + */
> + "LEN2131", /* ThinkPad P52 w/ NFC */
> + "LEN2132", /* ThinkPad P52 */
> + "LEN2133", /* ThinkPad P72 w/ NFC */
> + "LEN2134", /* ThinkPad P72 */
> + NULL
> +};
> +
> static int elantech_create_smbus(struct psmouse *psmouse,
> struct elantech_device_info *info,
> bool leave_breadcrumbs)
> @@ -1802,10 +1814,12 @@ static int elantech_setup_smbus(struct psmouse
> *psmouse,
>
> if (elantech_smbus == ELANTECH_SMBUS_NOT_SET) {
> /*
> - * New ICs are enabled by default.
> + * New ICs are enabled by default, unless mentioned in
> + * i2c_blacklist_pnp_ids.
> * Old ICs are up to the user to decide.
> */
> - if (!ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version))
> + if (!ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version) ||
> + psmouse_matches_pnp_id(psmouse, i2c_blacklist_pnp_ids))
> return -ENXIO;
> }
>
> --
> 2.19.2
>
