This is a note to let you know that I've just added the patch titled
usb: typec: tcpm: Properly interrupt VDM AMS
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 0bc3ee92880d910a1d100b73a781904f359e1f1c Mon Sep 17 00:00:00 2001
From: Kyle Tso <kyletso@xxxxxxxxxx>
Date: Sun, 23 May 2021 09:58:54 +0800
Subject: usb: typec: tcpm: Properly interrupt VDM AMS
When a VDM AMS is interrupted by Messages other than VDM, the AMS needs
to be finished properly. Also start a VDM AMS if receiving SVDM Commands
from the port partner to complement the functionality of tcpm_vdm_ams().
Fixes: 0908c5aca31e ("usb: typec: tcpm: AMS and Collision Avoidance")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Kyle Tso <kyletso@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210523015855.1785484-2-kyletso@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/typec/tcpm/tcpm.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 8fdfd7f65ad7..6ea5df3782cf 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -1550,6 +1550,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
if (PD_VDO_SVDM_VER(p[0]) < svdm_version)
typec_partner_set_svdm_version(port->partner,
PD_VDO_SVDM_VER(p[0]));
+
+ tcpm_ams_start(port, DISCOVER_IDENTITY);
/* 6.4.4.3.1: Only respond as UFP (device) */
if (port->data_role == TYPEC_DEVICE &&
port->nr_snk_vdo) {
@@ -1568,14 +1570,19 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
}
break;
case CMD_DISCOVER_SVID:
+ tcpm_ams_start(port, DISCOVER_SVIDS);
break;
case CMD_DISCOVER_MODES:
+ tcpm_ams_start(port, DISCOVER_MODES);
break;
case CMD_ENTER_MODE:
+ tcpm_ams_start(port, DFP_TO_UFP_ENTER_MODE);
break;
case CMD_EXIT_MODE:
+ tcpm_ams_start(port, 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;
@@ -2287,6 +2294,12 @@ static void tcpm_pd_data_request(struct tcpm_port *port,
bool frs_enable;
int ret;
+ if (tcpm_vdm_ams(port) && type != PD_DATA_VENDOR_DEF) {
+ port->vdm_state = VDM_STATE_ERR_BUSY;
+ tcpm_ams_finish(port);
+ mod_vdm_delayed_work(port, 0);
+ }
+
switch (type) {
case PD_DATA_SOURCE_CAP:
for (i = 0; i < cnt; i++)
@@ -2459,6 +2472,16 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
enum pd_ctrl_msg_type type = pd_header_type_le(msg->header);
enum tcpm_state next_state;
+ /*
+ * Stop VDM state machine if interrupted by other Messages while NOT_SUPP is allowed in
+ * VDM AMS if waiting for VDM responses and will be handled later.
+ */
+ if (tcpm_vdm_ams(port) && type != PD_CTRL_NOT_SUPP && type != PD_CTRL_GOOD_CRC) {
+ port->vdm_state = VDM_STATE_ERR_BUSY;
+ tcpm_ams_finish(port);
+ mod_vdm_delayed_work(port, 0);
+ }
+
switch (type) {
case PD_CTRL_GOOD_CRC:
case PD_CTRL_PING:
@@ -2717,6 +2740,13 @@ static void tcpm_pd_ext_msg_request(struct tcpm_port *port,
enum pd_ext_msg_type type = pd_header_type_le(msg->header);
unsigned int data_size = pd_ext_header_data_size_le(msg->ext_msg.header);
+ /* stopping VDM state machine if interrupted by other Messages */
+ if (tcpm_vdm_ams(port)) {
+ port->vdm_state = VDM_STATE_ERR_BUSY;
+ tcpm_ams_finish(port);
+ mod_vdm_delayed_work(port, 0);
+ }
+
if (!(le16_to_cpu(msg->ext_msg.header) & PD_EXT_HDR_CHUNKED)) {
tcpm_pd_handle_msg(port, PD_MSG_CTRL_NOT_SUPP, NONE_AMS);
tcpm_log(port, "Unchunked extended messages unsupported");
--
2.31.1
