usb: typec: ucsi: yoga-c630: correct response for GET_CURRENT_CAM

On Lenovo Yoga C630 the EC handles GET_CURRENT_CAM command, but it
returns 1 if DisplayPort is active and 0 otherwise. However in order to
let UCSI drivers handle AltModes correctly, it should return 0 / 0xff.
Correct returned value.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250621-c630-ucsi-v1-6-a86de5e11361@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/ucsi/ucsi_yoga_c630.c b/drivers/usb/typec/ucsi/ucsi_yoga_c630.c
index 506faf31b6e3a056e067f2bb69f5e9e5ea40e514..76afd128d42a2573ff55433f815c2773462a6426 100644 (file)
--- a/drivers/usb/typec/ucsi/ucsi_yoga_c630.c
+++ b/drivers/usb/typec/ucsi/ucsi_yoga_c630.c
@@ -111,7 +111,15 @@ static int yoga_c630_ucsi_sync_control(struct ucsi *ucsi,
                return 0;
        }
 
-       return ucsi_sync_control_common(ucsi, command, cci, data, size);
+       ret = ucsi_sync_control_common(ucsi, command, cci, data, size);
+       if (ret < 0)
+               return ret;
+
+       /* UCSI_GET_CURRENT_CAM is off-by-one on all ports */
+       if (UCSI_COMMAND(command) == UCSI_GET_CURRENT_CAM && data)
+               ((u8 *)data)[0]--;
+
+       return ret;
 }
 
 static bool yoga_c630_ucsi_update_altmodes(struct ucsi *ucsi,