usb: typec: intel_pmc_mux: Do not configure Altmode HPD High
authorUtkarsh Patel <utkarsh.h.patel@intel.com>
Mon, 7 Sep 2020 14:21:51 +0000 (17:21 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 17 Sep 2020 11:55:46 +0000 (13:55 +0200)
commit41e3571c02ec070c4428ee3d7f932167e3d5948b
tree610fd7245cbb73925f3618d4d050e5d0d3af4305
parentefec148aa4eb407b9e4d97adf473a3e847a43452
usb: typec: intel_pmc_mux: Do not configure Altmode HPD High

commit 294955fd43dbf1e8f3a84cffa4797c6f22badc31 upstream.

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>
drivers/usb/typec/mux/intel_pmc_mux.c