From: Madhusudanarao Amara <madhusudanarao.amara@xxxxxxxxx> commit 0f041b8592daaaea46e91a8ebb3b47e6e0171fd8 upstream. Warm reboot scenarios some times type C Mux driver gets Mux configuration request as HPD=1,IRQ=1. In that scenario typeC Mux driver need to configure Mux as follows as per IOM requirement: (1). Confgiure Mux HPD = 1, IRQ = 0 (2). Configure Mux with HPD = 1, IRQ = 1 IOM expects TypeC Mux configuration as follows: (1). HPD=1, IRQ=0 (2). HPD=1, IRQ=1 if IOM gets mux config request (2) without configuring (1), it will ignore the request. The impact of this is there is no DP_alt mode display. Fixes: 43d596e32276 ("usb: typec: intel_pmc_mux: Check the port status before connect") Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> Signed-off-by: Madhusudanarao Amara <madhusudanarao.amara@xxxxxxxxx> Link: https://lore.kernel.org/r/20201216140918.49197-1-madhusudanarao.amara@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/typec/mux/intel_pmc_mux.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/drivers/usb/typec/mux/intel_pmc_mux.c +++ b/drivers/usb/typec/mux/intel_pmc_mux.c @@ -202,10 +202,21 @@ static int pmc_usb_mux_dp_hpd(struct pmc_usb_port *port, struct typec_displayport_data *dp) { u8 msg[2] = { }; + int ret; msg[0] = PMC_USB_DP_HPD; msg[0] |= port->usb3_port << PMC_USB_MSG_USB3_PORT_SHIFT; + /* Configure HPD first if HPD,IRQ comes together */ + if (!IOM_PORT_HPD_ASSERTED(port->iom_status) && + dp->status & DP_STATUS_IRQ_HPD && + dp->status & DP_STATUS_HPD_STATE) { + msg[1] = PMC_USB_DP_HPD_LVL; + ret = pmc_usb_command(port, msg, sizeof(msg)); + if (ret) + return ret; + } + if (dp->status & DP_STATUS_IRQ_HPD) msg[1] = PMC_USB_DP_HPD_IRQ;