From 36f78477ac2c89e9a2eed4a31404a291a3450b5d Mon Sep 17 00:00:00 2001
From: ChiYuan Huang <cy_huang@richtek.com>
Date: Mon, 9 Jan 2023 15:19:50 +0800
Subject: [PATCH] usb: typec: tcpm: Fix altmode re-registration causes sysfs create fail
Git-commit: 36f78477ac2c89e9a2eed4a31404a291a3450b5d
Patch-mainline: v6.2-rc5
References: git-fixes

There's the altmode re-registeration issue after data role
swap (DR_SWAP).

Comparing to USBPD 2.0, in USBPD 3.0, it loose the limit that only DFP
can initiate the VDM command to get partner identity information.

For a USBPD 3.0 UFP device, it may already get the identity information
from its port partner before DR_SWAP. If DR_SWAP send or receive at the
mean time, 'send_discover' flag will be raised again. It causes discover
identify action restart while entering ready state. And after all
discover actions are done, the 'tcpm_register_altmodes' will be called.
If old altmode is not unregistered, this sysfs create fail can be found.

In 'DR_SWAP_CHANGE_DR' state case, only DFP will unregister altmodes.
For UFP, the original altmodes keep registered.

This patch fix the logic that after DR_SWAP, 'tcpm_unregister_altmodes'
must be called whatever the current data role is.

Reviewed-by: Macpaul Lin <macpaul.lin@mediatek.com>
Fixes: ae8a2ca8a221 ("usb: typec: Group all TCPCI/TCPM code together")
Reported-by: TommyYl Chen <tommyyl.chen@mediatek.com>
Cc: stable@vger.kernel.org
Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/1673248790-15794-1-git-send-email-cy_huang@richtek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/typec/tcpm/tcpm.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 904c7b4ce2f0..59b366b5c614 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4594,14 +4594,13 @@ static void run_state_machine(struct tcpm_port *port)
 		tcpm_set_state(port, ready_state(port), 0);
 		break;
 	case DR_SWAP_CHANGE_DR:
-		if (port->data_role == TYPEC_HOST) {
-			tcpm_unregister_altmodes(port);
+		tcpm_unregister_altmodes(port);
+		if (port->data_role == TYPEC_HOST)
 			tcpm_set_roles(port, true, port->pwr_role,
 				       TYPEC_DEVICE);
-		} else {
+		else
 			tcpm_set_roles(port, true, port->pwr_role,
 				       TYPEC_HOST);
-		}
 		tcpm_ams_finish(port);
 		tcpm_set_state(port, ready_state(port), 0);
 		break;
-- 
2.35.3