usb: typec: intel_pmc_mux: Do not configure Altmode HPD High

According to the PMC Type C Subsystem (TCSS) Mux programming guide rev
0.7, bit 14 is reserved in Alternate mode.
In DP Alternate Mode state, if the HPD_STATE (bit 7) field in the
status update command VDO is set to HPD_HIGH, HPD is configured via
separate HPD mode request after configuring DP Alternate mode request.
Configuring reserved bit may show unexpected behaviour.
So do not configure them while issuing the Alternate Mode request.

Fixes: 7990be48ef4d ("usb: typec: mux: intel: Handle alt mode HPD_HIGH")
Cc: stable@vger.kernel.org
Signed-off-by: Utkarsh Patel <utkarsh.h.patel@intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20200907142152.35678-2-heikki.krogerus@linux.intel.com
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 fd9008f..bb9cb4e 100644 (file)
--- a/drivers/usb/typec/mux/intel_pmc_mux.c
+++ b/drivers/usb/typec/mux/intel_pmc_mux.c
@@ -68,7 +68,6 @@ enum {
 #define PMC_USB_ALTMODE_DP_MODE_SHIFT  8
 
 /* TBT specific Mode Data bits */
-#define PMC_USB_ALTMODE_HPD_HIGH       BIT(14)
 #define PMC_USB_ALTMODE_TBT_TYPE       BIT(17)
 #define PMC_USB_ALTMODE_CABLE_TYPE     BIT(18)
 #define PMC_USB_ALTMODE_ACTIVE_LINK    BIT(20)
@@ -185,9 +184,6 @@ 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_ALTMODE_HPD_HIGH;
-
        ret = pmc_usb_command(port, (void *)&req, sizeof(req));
        if (ret)
                return ret;