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@google.com 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@vger.kernel.org Reviewed-by: Guenter Roeck linux@roeck-us.net Acked-by: Heikki Krogerus heikki.krogerus@linux.intel.com Signed-off-by: Kyle Tso kyletso@google.com Link: https://lore.kernel.org/r/20210523015855.1785484-2-kyletso@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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");