usb: typec: mux: intel: Handle alt mode HPD_HIGH

According to the PMC Type C Subsystem (TCSS) Mux programming guide rev
0.6, when a device is transitioning to DP Alternate Mode state, if the
HPD_STATE (bit 7) field in the status update command VDO is set to
HPD_HIGH, the HPD_HIGH field in the Alternate Mode request “mode_data”
field (bit 14) should also be set. Ensure the bit is correctly handled
while issuing the Alternate Mode request.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Fixes: 6701adfa9693 ("usb: typec: driver for Intel PMC mux control")
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20200429054432.134178-1-pmalani@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/mux/intel_pmc_mux.c b/drivers/usb/typec/mux/intel_pmc_mux.c
index bb23886..67c5139 100644 (file)
--- a/drivers/usb/typec/mux/intel_pmc_mux.c
+++ b/drivers/usb/typec/mux/intel_pmc_mux.c
@@ -157,6 +157,10 @@ pmc_usb_mux_dp(struct pmc_usb_port *port, struct typec_mux_state *state)
        req.mode_data |= (state->mode - TYPEC_STATE_MODAL) <<
                         PMC_USB_ALTMODE_DP_MODE_SHIFT;
 
+       if (data->status & DP_STATUS_HPD_STATE)
+               req.mode_data |= PMC_USB_DP_HPD_LVL <<
+                                PMC_USB_ALTMODE_DP_MODE_SHIFT;
+
        return pmc_usb_command(port, (void *)&req, sizeof(req));
 }