]> git.ipfire.org Git - thirdparty/kernel/stable.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, 19 Jan 2026 12:11:46 +0000 (13:11 +0100)
commit07c8d2a109d847775b3b4e2c3294c8e1eea75432
tree71a25a5206a3a25158015fa3776e7dc116020d04
parent3c87923d752bfea86155918687273163086aacb2
usb: typec: ucsi: Handle incorrect num_connectors capability

[ Upstream commit 30cd2cb1abf4c4acdb1ddb468c946f68939819fb ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/usb/typec/ucsi/ucsi.c