]> git.ipfire.org Git - thirdparty/kernel/linux.git/commit
usb: typec: ucsi: Handle incorrect num_connectors capability
authorMark Pearson <mpearson-lenovo@squebb.ca>
Thu, 21 Aug 2025 18:53:07 +0000 (14:53 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 13 Oct 2025 07:34:32 +0000 (09:34 +0200)
commit30cd2cb1abf4c4acdb1ddb468c946f68939819fb
treef20664d68de62cbf5a3949eaa15688423c80a5a9
parent5570ad1423ee60f6e972dadb63fb2e5f90a54cbe
usb: typec: ucsi: Handle incorrect num_connectors capability

The UCSI spec states that the num_connectors field is 7 bits, and the
8th bit is reserved and should be set to zero.
Some buggy FW has been known to set this bit, and it can lead to a
system not booting.
Flag that the FW is not behaving correctly, and auto-fix the value
so that the system boots correctly.

Found on Lenovo P1 G8 during Linux enablement program. The FW will
be fixed, but seemed worth addressing in case it hit platforms that
aren't officially Linux supported.

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250821185319.2585023-1-mpearson-lenovo@squebb.ca
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/typec/ucsi/ucsi.c