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Pablo Sun
c1e5c2f0cb
Fix incorrect pin assignment values when connecting to a monitor with
Type-C receptacle instead of a plug.
According to specification, an UFP_D receptacle's pin assignment
should came from the UFP_D pin assignments field (bit 23:16), while
an UFP_D plug's assignments are described in the DFP_D pin assignments
(bit 15:8) during Mode Discovery.
For example the LG 27 UL850-W is a monitor with Type-C receptacle.
The monitor responds to MODE DISCOVERY command with following
DisplayPort Capability flag:
dp->alt->vdo=0x140045
The existing logic only take cares of UPF_D plug case,
and would take the bit 15:8 for this 0x140045 case.
This results in an non-existing pin assignment 0x0 in
dp_altmode_configure.
To fix this problem a new set of macros are introduced
to take plug/receptacle differences into consideration.
Fixes: 0e3bb7d689 ("usb: typec: Add driver for DisplayPort alternate mode")
Cc: [email protected]
Co-developed-by: Pablo Sun <[email protected]>
Co-developed-by: Macpaul Lin <[email protected]>
Reviewed-by: Guillaume Ranquet <[email protected]>
Reviewed-by: Heikki Krogerus <[email protected]>
Signed-off-by: Pablo Sun <[email protected]>
Signed-off-by: Macpaul Lin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>