usb: ucsi_acpi: Quirk to ack a connector change ack cmd

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The PPM on some Dell laptops seems to expect that the ACK_CC_CI
command to clear the connector change notification is in turn
followed by another ACK_CC_CI to acknowledge the ACK_CC_CI command
itself. This is in violation of the UCSI spec that states:

    "The only notification that is not acknowledged by the OPM is
     the command completion notification for the ACK_CC_CI or the
     PPM_RESET command."

Add a quirk to send this ack anyway.
Apply the quirk to all Dell systems.

On the first command that acks a connector change send a dummy
command to determine if it runs into a timeout. Only activate
the quirk if it does. This ensure that we do not break Dell
systems that do not need the quirk.

Signed-off-by: "Christian A. Ehrhardt" <lk@c--e.de>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240121204123.275441-4-lk@c--e.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Christian A. Ehrhardt 2024-01-21 21:41:23 +01:00 • committed by Greg Kroah-Hartman

parent 2840143e39

commit f3be347ea4

1 changed files with 68 additions and 3 deletions

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drivers/usb/typec/ucsi/ucsi_acpi.c

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