[PATCH 5.12 127/173] usb: typec: tcpm: Fix misuses of AMS invocation

From: Greg Kroah-Hartman
Date: Mon Jun 14 2021 - 07:33:24 EST


From: Kyle Tso <kyletso@xxxxxxxxxx>

commit 80137c18737c30d20ee630e442405236d96898a7 upstream.

tcpm_ams_start is used to initiate an AMS as well as checking Collision
Avoidance conditions but not for flagging passive AMS (initiated by the
port partner). Fix the misuses of tcpm_ams_start in tcpm_pd_svdm.

ATTENTION doesn't need responses so the AMS flag is not needed here.

Fixes: 0bc3ee92880d ("usb: typec: tcpm: Properly interrupt VDM AMS")
Signed-off-by: Kyle Tso <kyletso@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210601123151.3441914-5-kyletso@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/typec/tcpm/tcpm.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -1537,7 +1537,7 @@ static int tcpm_pd_svdm(struct tcpm_port
svdm_version = PD_VDO_SVDM_VER(p[0]);
}

- tcpm_ams_start(port, DISCOVER_IDENTITY);
+ port->ams = DISCOVER_IDENTITY;
/*
* PD2.0 Spec 6.10.3: respond with NAK as DFP (data host)
* PD3.1 Spec 6.4.4.2.5.1: respond with NAK if "invalid field" or
@@ -1560,19 +1560,18 @@ static int tcpm_pd_svdm(struct tcpm_port
}
break;
case CMD_DISCOVER_SVID:
- tcpm_ams_start(port, DISCOVER_SVIDS);
+ port->ams = DISCOVER_SVIDS;
break;
case CMD_DISCOVER_MODES:
- tcpm_ams_start(port, DISCOVER_MODES);
+ port->ams = DISCOVER_MODES;
break;
case CMD_ENTER_MODE:
- tcpm_ams_start(port, DFP_TO_UFP_ENTER_MODE);
+ port->ams = DFP_TO_UFP_ENTER_MODE;
break;
case CMD_EXIT_MODE:
- tcpm_ams_start(port, DFP_TO_UFP_EXIT_MODE);
+ port->ams = DFP_TO_UFP_EXIT_MODE;
break;
case CMD_ATTENTION:
- tcpm_ams_start(port, ATTENTION);
/* Attention command does not have response */
*adev_action = ADEV_ATTENTION;
return 0;