6.15-stable review patch. If anyone has any objections, please let me know.
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From: Johan Hovold johan+linaro@kernel.org
commit 5090ac9191a19c61beeade60d3d839e509fab640 upstream.
The PMIC GLINK driver is currently generating DisplayPort hotplug notifications whenever something is connected to (or disconnected from) a port regardless of the type of notification sent by the firmware.
These notifications are forwarded to user space by the DRM subsystem as connector "change" uevents:
KERNEL[1556.223776] change /devices/platform/soc@0/ae00000.display-subsystem/ae01000.display-controller/drm/card0 (drm) ACTION=change DEVPATH=/devices/platform/soc@0/ae00000.display-subsystem/ae01000.display-controller/drm/card0 SUBSYSTEM=drm HOTPLUG=1 CONNECTOR=36 DEVNAME=/dev/dri/card0 DEVTYPE=drm_minor SEQNUM=4176 MAJOR=226 MINOR=0
On the Lenovo ThinkPad X13s and T14s, the PMIC GLINK firmware sends two identical notifications with orientation information when connecting a charger, each generating a bogus DRM hotplug event. On the X13s, two such notification are also sent every 90 seconds while a charger remains connected, which again are forwarded to user space:
port = 1, svid = ff00, mode = 255, hpd_state = 0 payload = 01 00 00 00 00 00 00 ff 00 00 00 00 00 00 00 00
Note that the firmware only sends on of these when connecting an ethernet adapter.
Fix the spurious hotplug events by only forwarding hotplug notifications for the Type-C DisplayPort service id. This also reduces the number of uevents from four to two when an actual DisplayPort altmode device is connected:
port = 0, svid = ff01, mode = 2, hpd_state = 0 payload = 00 01 02 00 f2 0c 01 ff 03 00 00 00 00 00 00 00 port = 0, svid = ff01, mode = 2, hpd_state = 1 payload = 00 01 02 00 f2 0c 01 ff 43 00 00 00 00 00 00 00
Fixes: 080b4e24852b ("soc: qcom: pmic_glink: Introduce altmode support") Cc: stable@vger.kernel.org # 6.3 Cc: Bjorn Andersson andersson@kernel.org Reported-by: Clayton Craft clayton@craftyguy.net Signed-off-by: Johan Hovold johan+linaro@kernel.org Acked-by: Konrad Dybcio konrad.dybcio@oss.qualcomm.com Tested-by: Clayton Craft clayton@craftyguy.net Link: https://lore.kernel.org/r/20250324132448.6134-1-johan+linaro@kernel.org Signed-off-by: Bjorn Andersson andersson@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/soc/qcom/pmic_glink_altmode.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-)
--- a/drivers/soc/qcom/pmic_glink_altmode.c +++ b/drivers/soc/qcom/pmic_glink_altmode.c @@ -218,21 +218,29 @@ static void pmic_glink_altmode_worker(st { struct pmic_glink_altmode_port *alt_port = work_to_altmode_port(work); struct pmic_glink_altmode *altmode = alt_port->altmode; + enum drm_connector_status conn_status;
typec_switch_set(alt_port->typec_switch, alt_port->orientation);
- if (alt_port->svid == USB_TYPEC_DP_SID && alt_port->mode == 0xff) - pmic_glink_altmode_safe(altmode, alt_port); - else if (alt_port->svid == USB_TYPEC_DP_SID) - pmic_glink_altmode_enable_dp(altmode, alt_port, alt_port->mode, - alt_port->hpd_state, alt_port->hpd_irq); - else - pmic_glink_altmode_enable_usb(altmode, alt_port); + if (alt_port->svid == USB_TYPEC_DP_SID) { + if (alt_port->mode == 0xff) { + pmic_glink_altmode_safe(altmode, alt_port); + } else { + pmic_glink_altmode_enable_dp(altmode, alt_port, + alt_port->mode, + alt_port->hpd_state, + alt_port->hpd_irq); + } + + if (alt_port->hpd_state) + conn_status = connector_status_connected; + else + conn_status = connector_status_disconnected;
- drm_aux_hpd_bridge_notify(&alt_port->bridge->dev, - alt_port->hpd_state ? - connector_status_connected : - connector_status_disconnected); + drm_aux_hpd_bridge_notify(&alt_port->bridge->dev, conn_status); + } else { + pmic_glink_altmode_enable_usb(altmode, alt_port); + }
pmic_glink_altmode_request(altmode, ALTMODE_PAN_ACK, alt_port->index); }