Re: [PATCH v3 10/12] usb: typec: tcpm: add discover svids and discover modes support for sop'

Heikki Krogerus
2024-01-15T09:14:58Z

On Mon, Jan 08, 2024 at 07:16:23PM +0000, RD Babiera wrote:
> Adds Discover SVIDs and Discover Modes support for SOP' and Alt Mode
> SVDM support over SOP'. tcpm_port adds separate Alt Mode data for SOP'.
>
> svdm_consume_svids and svdm_consume_modes take the received SVDM's SOP*
> type to store svids/modes separately, and tcpm_register_plug_altmodes
> registers the active cable's alt modes.
>
> In tcpm_pd_svdm, the port will send Discover SVIDs to SOP' after Discover
> Modes on SOP if the connected cable is an active cable. Discover Modes on
> SOP' is sent following Discover SVIDs on SOP. Registering partner alt modes
> is delayed when an active cable is present until Discover Modes completes
> on SOP', or if the Discover SVIDs/Discover Modes request on SOP' encounters
> a transmission error.
>
> Signed-off-by: RD Babiera <rdbabiera@google.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
> Changes since v2:
> * v2 replaced code that unregistered partner altmodes instead of adding,
> readded to tcpm_unregister_altmodes.
>
> Changes since v1:
> * Changes to tcpm_altmode_enter/exit/vdm are moved to next patch
> * adev_action changes are moved to next patch
> ---
> drivers/usb/typec/tcpm/tcpm.c | 161 +++++++++++++++++++++++++++++-----
> 1 file changed, 140 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 1ce525c8f97c..d16edf112858 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -477,7 +477,9 @@ struct tcpm_port {
>
> /* Alternate mode data */
> struct pd_mode_data mode_data;
> + struct pd_mode_data mode_data_prime;
> struct typec_altmode *partner_altmode[ALTMODE_DISCOVERY_MAX];
> + struct typec_altmode *plug_prime_altmode[ALTMODE_DISCOVERY_MAX];
> struct typec_altmode *port_altmode[ALTMODE_DISCOVERY_MAX];
>
> /* Deadline in jiffies to exit src_try_wait state */
> @@ -1636,9 +1638,11 @@ static void svdm_consume_identity_sop_prime(struct tcpm_port *port, const u32 *p
> }
> }
>
> -static bool svdm_consume_svids(struct tcpm_port *port, const u32 *p, int cnt)
> +static bool svdm_consume_svids(struct tcpm_port *port, const u32 *p, int cnt,
> + enum tcpm_transmit_type rx_sop_type)
> {
> - struct pd_mode_data *pmdata = &port->mode_data;
> + struct pd_mode_data *pmdata = rx_sop_type == TCPC_TX_SOP_PRIME ?
> + &port->mode_data_prime : &port->mode_data;
> int i;
>
> for (i = 1; i < cnt; i++) {
> @@ -1684,14 +1688,29 @@ static bool svdm_consume_svids(struct tcpm_port *port, const u32 *p, int cnt)
> return false;
> }
>
> -static void svdm_consume_modes(struct tcpm_port *port, const u32 *p, int cnt)
> +static void svdm_consume_modes(struct tcpm_port *port, const u32 *p, int cnt,
> + enum tcpm_transmit_type rx_sop_type)
> {
> struct pd_mode_data *pmdata = &port->mode_data;
> struct typec_altmode_desc *paltmode;
> int i;
>
> - if (pmdata->altmodes >= ARRAY_SIZE(port->partner_altmode)) {
> - /* Already logged in svdm_consume_svids() */
> + switch (rx_sop_type) {
> + case TCPC_TX_SOP_PRIME:
> + pmdata = &port->mode_data_prime;
> + if (pmdata->altmodes >= ARRAY_SIZE(port->plug_prime_altmode)) {
> + /* Already logged in svdm_consume_svids() */
> + return;
> + }
> + break;
> + case TCPC_TX_SOP:
> + pmdata = &port->mode_data;
> + if (pmdata->altmodes >= ARRAY_SIZE(port->partner_altmode)) {
> + /* Already logged in svdm_consume_svids() */
> + return;
> + }
> + break;
> + default:
> return;
> }
>
> @@ -1729,7 +1748,28 @@ static void tcpm_register_partner_altmodes(struct tcpm_port *port)
> }
> }
>
> +static void tcpm_register_plug_altmodes(struct tcpm_port *port)
> +{
> + struct pd_mode_data *modep = &port->mode_data_prime;
> + struct typec_altmode *altmode;
> + int i;
> +
> + typec_plug_set_num_altmodes(port->plug_prime, modep->altmodes);
> +
> + for (i = 0; i < modep->altmodes; i++) {
> + altmode = typec_plug_register_altmode(port->plug_prime,
> + &modep->altmode_desc[i]);
> + if (IS_ERR(altmode)) {
> + tcpm_log(port, "Failed to register plug SVID 0x%04x",
> + modep->altmode_desc[i].svid);
> + altmode = NULL;
> + }
> + port->plug_prime_altmode[i] = altmode;
> + }
> +}
> +
> #define supports_modal(port) PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
> +#define supports_modal_cable(port) PD_IDH_MODAL_SUPP((port)->cable_ident.id_header)
> #define supports_host(port) PD_IDH_HOST_SUPP((port->partner_ident.id_header))
>
> /*
> @@ -1807,6 +1847,15 @@ static bool tcpm_attempt_vconn_swap_discovery(struct tcpm_port *port)
> return false;
> }
>
> +
> +static bool tcpm_cable_vdm_supported(struct tcpm_port *port)
> +{
> + return !IS_ERR_OR_NULL(port->cable) &&
> + typec_cable_is_active(port->cable) &&
> + supports_modal_cable(port) &&
> + tcpm_can_communicate_sop_prime(port);
> +}
> +
> static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
> const u32 *p, int cnt, u32 *response,
> enum adev_actions *adev_action,
> @@ -1814,8 +1863,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
> enum tcpm_transmit_type *response_tx_sop_type)
> {
> struct typec_port *typec = port->typec_port;
> - struct typec_altmode *pdev;
> - struct pd_mode_data *modep;
> + struct typec_altmode *pdev, *pdev_prime;
> + struct pd_mode_data *modep, *modep_prime;
> int svdm_version;
> int rlen = 0;
> int cmd_type;
> @@ -1836,6 +1885,11 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
>
> switch (rx_sop_type) {
> case TCPC_TX_SOP_PRIME:
> + modep_prime = &port->mode_data_prime;
> + pdev_prime = typec_match_altmode(port->plug_prime_altmode,
> + ALTMODE_DISCOVERY_MAX,
> + PD_VDO_VID(p[0]),
> + PD_VDO_OPOS(p[0]));
> if (!IS_ERR_OR_NULL(port->cable)) {
> svdm_version = typec_get_cable_svdm_version(typec);
> if (PD_VDO_SVDM_VER(p[0]) < svdm_version)
> @@ -1843,11 +1897,21 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
> }
> break;
> case TCPC_TX_SOP:
> + modep = &port->mode_data;
> + pdev = typec_match_altmode(port->partner_altmode,
> + ALTMODE_DISCOVERY_MAX,
> + PD_VDO_VID(p[0]),
> + PD_VDO_OPOS(p[0]));
> svdm_version = typec_get_negotiated_svdm_version(typec);
> if (svdm_version < 0)
> return 0;
> break;
> default:
> + modep = &port->mode_data;
> + pdev = typec_match_altmode(port->partner_altmode,
> + ALTMODE_DISCOVERY_MAX,
> + PD_VDO_VID(p[0]),
> + PD_VDO_OPOS(p[0]));
> svdm_version = typec_get_negotiated_svdm_version(typec);
> if (svdm_version < 0)
> return 0;
> @@ -1939,6 +2003,9 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
> * SOP' Discover Identity
> * SOP Discover SVIDs
> * Discover Modes
> + * (Active Cables)
> + * SOP' Discover SVIDs
> + * Discover Modes
> *
> * Perform Discover SOP' if the port can communicate with cable
> * plug.
> @@ -2018,26 +2085,62 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
> }
> break;
> case CMD_DISCOVER_SVID:
> + *response_tx_sop_type = rx_sop_type;
> /* 6.4.4.3.2 */
> - if (svdm_consume_svids(port, p, cnt)) {
> + if (svdm_consume_svids(port, p, cnt, rx_sop_type)) {
> response[0] = VDO(USB_SID_PD, 1, svdm_version, CMD_DISCOVER_SVID);
> rlen = 1;
> - } else if (modep->nsvids && supports_modal(port)) {
> - response[0] = VDO(modep->svids[0], 1, svdm_version,
> - CMD_DISCOVER_MODES);
> - rlen = 1;
> + } else {
> + if (rx_sop_type == TCPC_TX_SOP) {
> + if (modep->nsvids && supports_modal(port)) {
> + response[0] = VDO(modep->svids[0], 1, svdm_version,
> + CMD_DISCOVER_MODES);
> + rlen = 1;
> + }
> + } else if (rx_sop_type == TCPC_TX_SOP_PRIME) {
> + if (modep_prime->nsvids) {
> + response[0] = VDO(modep_prime->svids[0], 1,
> + svdm_version, CMD_DISCOVER_MODES);
> + rlen = 1;
> + }
> + }
> }
> break;
> case CMD_DISCOVER_MODES:
> - /* 6.4.4.3.3 */
> - svdm_consume_modes(port, p, cnt);
> - modep->svid_index++;
> - if (modep->svid_index < modep->nsvids) {
> - u16 svid = modep->svids[modep->svid_index];
> - response[0] = VDO(svid, 1, svdm_version, CMD_DISCOVER_MODES);
> - rlen = 1;
> - } else {
> - tcpm_register_partner_altmodes(port);
> + if (rx_sop_type == TCPC_TX_SOP) {
> + /* 6.4.4.3.3 */
> + svdm_consume_modes(port, p, cnt, rx_sop_type);
> + modep->svid_index++;
> + if (modep->svid_index < modep->nsvids) {
> + u16 svid = modep->svids[modep->svid_index];
> + *response_tx_sop_type = TCPC_TX_SOP;
> + response[0] = VDO(svid, 1, svdm_version,
> + CMD_DISCOVER_MODES);
> + rlen = 1;
> + } else if (tcpm_cable_vdm_supported(port)) {
> + *response_tx_sop_type = TCPC_TX_SOP_PRIME;
> + response[0] = VDO(USB_SID_PD, 1,
> + typec_get_cable_svdm_version(typec),
> + CMD_DISCOVER_SVID);
> + rlen = 1;
> + } else {
> + tcpm_register_partner_altmodes(port);
> + }
> + } else if (rx_sop_type == TCPC_TX_SOP_PRIME) {
> + /* 6.4.4.3.3 */
> + svdm_consume_modes(port, p, cnt, rx_sop_type);
> + modep_prime->svid_index++;
> + if (modep_prime->svid_index < modep_prime->nsvids) {
> + u16 svid = modep_prime->svids[modep_prime->svid_index];
> + *response_tx_sop_type = TCPC_TX_SOP_PRIME;
> + response[0] = VDO(svid, 1,
> + typec_get_cable_svdm_version(typec),
> + CMD_DISCOVER_MODES);
> + rlen = 1;
> + } else {
> + tcpm_register_plug_altmodes(port);
> + tcpm_register_partner_altmodes(port);
> + }
> }
> break;
> case CMD_ENTER_MODE:
> @@ -2418,6 +2521,16 @@ static void vdm_run_state_machine(struct tcpm_port *port)
> tcpm_queue_vdm(port, response[0], &response[1],
> 0, TCPC_TX_SOP);
> break;
> + /*
> + * If Discover SVIDs or Discover Modes fail, then
> + * proceed with Alt Mode discovery process on SOP.
> + */
> + case CMD_DISCOVER_SVID:
> + tcpm_register_partner_altmodes(port);
> + break;
> + case CMD_DISCOVER_MODES:
> + tcpm_register_partner_altmodes(port);
> + break;
> default:
> break;
> }
> @@ -4124,14 +4237,20 @@ static void tcpm_typec_disconnect(struct tcpm_port *port)
> static void tcpm_unregister_altmodes(struct tcpm_port *port)
> {
> struct pd_mode_data *modep = &port->mode_data;
> + struct pd_mode_data *modep_prime = &port->mode_data_prime;
> int i;
>
> for (i = 0; i < modep->altmodes; i++) {
> typec_unregister_altmode(port->partner_altmode[i]);
> port->partner_altmode[i] = NULL;
> }
> + for (i = 0; i < modep_prime->altmodes; i++) {
> + typec_unregister_altmode(port->plug_prime_altmode[i]);
> + port->plug_prime_altmode[i] = NULL;
> + }
>
> memset(modep, 0, sizeof(*modep));
> + memset(modep_prime, 0, sizeof(*modep_prime));
> }
>
> static void tcpm_set_partner_usb_comm_capable(struct tcpm_port *port, bool capable)
> --
> 2.43.0.472.g3155946c3a-goog

--
heikki