On Sun, May 23, 2021 at 09:58:54AM +0800, Kyle Tso wrote:
> 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")
> Signed-off-by: Kyle Tso <kyletso@xxxxxxxxxx>
> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> ---
> 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 3feaf5d6419e..7db6ae3e9c0b 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -1578,6 +1578,8 @@ 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) {
> @@ -1596,14 +1598,19 @@ 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;
> @@ -2315,6 +2322,12 @@ 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++)
> @@ -2487,6 +2500,16 @@ 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:
> @@ -2745,6 +2768,13 @@ 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 (!(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");
> --
> 2.31.1.818.g46aad6cb9e-goog
--
heikki
