]> git.ipfire.org Git - thirdparty/linux.git/commit
usb: typec: ucsi: psy: Set current max to 100mA for BC 1.2 and Default
authorBenson Leung <bleung@chromium.org>
Thu, 17 Jul 2025 20:08:05 +0000 (20:08 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 21 Jul 2025 14:33:06 +0000 (16:33 +0200)
commitaf833e7f7db3cf4c82f063668e1b52297a30ec18
tree72d50534d8c9a26c44501e4fb6489064dadac533
parent1e61f6ab08786d66a11cfc51e13d6f08a6b06c56
usb: typec: ucsi: psy: Set current max to 100mA for BC 1.2 and Default

ucsi_psy_get_current_max would return 0mA as the maximum current if
UCSI detected a BC or a Default USB Power sporce.

The comment in this function is true that we can't tell the difference
between DCP/CDP or SDP chargers, but we can guarantee that at least 1-unit
of USB 1.1/2.0 power is available, which is 100mA, which is a better
fallback value than 0, which causes some userspaces, including the ChromeOS
power manager, to regard this as a power source that is not providing
any power.

In reality, 100mA is guaranteed from all sources in these classes.

Signed-off-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Jameson Thies <jthies@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20250717200805.3710473-1-bleung@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/typec/ucsi/psy.c
drivers/usb/typec/ucsi/ucsi.h