[PATCH] usb: typec: tcpm: Fix VDM type for Enter Mode commands

From: Andy Yan

Date: Thu Jun 04 2026 - 06:55:26 EST


VDO() second parameter is VDM type (bit 15): 1 for SVDM, 0 for UVDM.
Using 'vdo ? 2 : 1' corrupts SVID low bit when vdo is non-NULL
(2 << 15 = BIT(16)). Enter Mode is always SVDM, hardcode to 1.

Fixes: 8face9aa57c8 ("usb: typec: Add parameter for the VDO to typec_altmode_enter()")
Signed-off-by: Andy Yan <andyshrk@xxxxxxx>
---

drivers/usb/typec/tcpm/tcpm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 55fee96d3342a..3674e1cdde57b 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -3061,7 +3061,7 @@ static int tcpm_altmode_enter(struct typec_altmode *altmode, u32 *vdo)
if (svdm_version < 0)
return svdm_version;

- header = VDO(altmode->svid, vdo ? 2 : 1, svdm_version, CMD_ENTER_MODE);
+ header = VDO(altmode->svid, 1, svdm_version, CMD_ENTER_MODE);
header |= VDO_OPOS(altmode->mode);

return tcpm_queue_vdm_unlocked(port, header, vdo, vdo ? 1 : 0, TCPC_TX_SOP);
@@ -3109,7 +3109,7 @@ static int tcpm_cable_altmode_enter(struct typec_altmode *altmode, enum typec_pl
if (svdm_version < 0)
return svdm_version;

- header = VDO(altmode->svid, vdo ? 2 : 1, svdm_version, CMD_ENTER_MODE);
+ header = VDO(altmode->svid, 1, svdm_version, CMD_ENTER_MODE);
header |= VDO_OPOS(altmode->mode);

return tcpm_queue_vdm_unlocked(port, header, vdo, vdo ? 1 : 0, TCPC_TX_SOP_PRIME);
--
2.43.0