On Wed, Dec 16, 2020 at 10:20:47PM -0800, Jack Pham wrote:
> From: Mayank Rana <mrana@xxxxxxxxxxxxxx>
>
> UCSI already conveys the information about a port's connection
> status, whether it is operating in UFP or DFP mode, and whether the
> partner supports USB data or not. This information can be used to
> notify a dual-role controller to start up its host or peripheral
> mode accordingly. Add optional support for this by querying each
> port's fwnode to look for an associated USB role switch device.
> If present, call usb_role_switch_set() with the determined data
> role upon Connect Change or Connector Partner Change updates.
>
> Signed-off-by: Mayank Rana <mrana@xxxxxxxxxxxxxx>
> Signed-off-by: Jack Pham <jackp@xxxxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> ---
> drivers/usb/typec/ucsi/ucsi.c | 55 +++++++++++++++++++++++++++++++++--
> drivers/usb/typec/ucsi/ucsi.h | 3 ++
> 2 files changed, 55 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> index 51a570d40a42..8d3e3518a506 100644
> --- a/drivers/usb/typec/ucsi/ucsi.c
> +++ b/drivers/usb/typec/ucsi/ucsi.c
> @@ -588,6 +588,7 @@ static void ucsi_unregister_partner(struct ucsi_connector *con)
>
> static void ucsi_partner_change(struct ucsi_connector *con)
> {
> + enum usb_role u_role = USB_ROLE_NONE;
> int ret;
>
> if (!con->partner)
> @@ -595,11 +596,14 @@ static void ucsi_partner_change(struct ucsi_connector *con)
>
> switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) {
> case UCSI_CONSTAT_PARTNER_TYPE_UFP:
> - case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
> case UCSI_CONSTAT_PARTNER_TYPE_CABLE_AND_UFP:
> + u_role = USB_ROLE_HOST;
> + fallthrough;
> + case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
> typec_set_data_role(con->port, TYPEC_HOST);
> break;
> case UCSI_CONSTAT_PARTNER_TYPE_DFP:
> + u_role = USB_ROLE_DEVICE;
> typec_set_data_role(con->port, TYPEC_DEVICE);
> break;
> default:
> @@ -610,6 +614,15 @@ static void ucsi_partner_change(struct ucsi_connector *con)
> if (!completion_done(&con->complete))
> complete(&con->complete);
>
> + /* Only notify USB controller if partner supports USB data */
> + if (!(UCSI_CONSTAT_PARTNER_FLAGS(con->status.flags) & UCSI_CONSTAT_PARTNER_FLAG_USB))
> + u_role = USB_ROLE_NONE;
> +
> + ret = usb_role_switch_set_role(con->usb_role_sw, u_role);
> + if (ret)
> + dev_err(con->ucsi->dev, "con:%d: failed to set usb role:%d\n",
> + con->num, u_role);
> +
> /* Can't rely on Partner Flags field. Always checking the alt modes. */
> ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_SOP);
> if (ret)
> @@ -626,6 +639,7 @@ static void ucsi_handle_connector_change(struct work_struct *work)
> work);
> struct ucsi *ucsi = con->ucsi;
> enum typec_role role;
> + enum usb_role u_role = USB_ROLE_NONE;
> u64 command;
> int ret;
>
> @@ -661,11 +675,14 @@ static void ucsi_handle_connector_change(struct work_struct *work)
>
> switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) {
> case UCSI_CONSTAT_PARTNER_TYPE_UFP:
> - case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
> case UCSI_CONSTAT_PARTNER_TYPE_CABLE_AND_UFP:
> + u_role = USB_ROLE_HOST;
> + fallthrough;
> + case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
> typec_set_data_role(con->port, TYPEC_HOST);
> break;
> case UCSI_CONSTAT_PARTNER_TYPE_DFP:
> + u_role = USB_ROLE_DEVICE;
> typec_set_data_role(con->port, TYPEC_DEVICE);
> break;
> default:
> @@ -678,6 +695,16 @@ static void ucsi_handle_connector_change(struct work_struct *work)
> ucsi_unregister_partner(con);
>
> ucsi_port_psy_changed(con);
> +
> + /* Only notify USB controller if partner supports USB data */
> + if (!(UCSI_CONSTAT_PARTNER_FLAGS(con->status.flags) &
> + UCSI_CONSTAT_PARTNER_FLAG_USB))
> + u_role = USB_ROLE_NONE;
> +
> + ret = usb_role_switch_set_role(con->usb_role_sw, u_role);
> + if (ret)
> + dev_err(ucsi->dev, "con:%d: failed to set usb role:%d\n",
> + con->num, u_role);
> }
>
> if (con->status.change & UCSI_CONSTAT_CAM_CHANGE) {
> @@ -903,6 +930,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
> struct ucsi_connector *con = &ucsi->connector[index];
> struct typec_capability *cap = &con->typec_cap;
> enum typec_accessory *accessory = cap->accessory;
> + enum usb_role u_role = USB_ROLE_NONE;
> u64 command;
> int ret;
>
> @@ -981,11 +1009,14 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
>
> switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) {
> case UCSI_CONSTAT_PARTNER_TYPE_UFP:
> - case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
> case UCSI_CONSTAT_PARTNER_TYPE_CABLE_AND_UFP:
> + u_role = USB_ROLE_HOST;
> + fallthrough;
> + case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
> typec_set_data_role(con->port, TYPEC_HOST);
> break;
> case UCSI_CONSTAT_PARTNER_TYPE_DFP:
> + u_role = USB_ROLE_DEVICE;
> typec_set_data_role(con->port, TYPEC_DEVICE);
> break;
> default:
> @@ -1001,6 +1032,24 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
> ucsi_port_psy_changed(con);
> }
>
> + con->usb_role_sw = fwnode_usb_role_switch_get(cap->fwnode);
> + if (IS_ERR(con->usb_role_sw)) {
> + dev_err(ucsi->dev, "con%d: failed to get usb role switch\n",
> + con->num);
> + con->usb_role_sw = NULL;
> + }
> +
> + /* Only notify USB controller if partner supports USB data */
> + if (!(UCSI_CONSTAT_PARTNER_FLAGS(con->status.flags) & UCSI_CONSTAT_PARTNER_FLAG_USB))
> + u_role = USB_ROLE_NONE;
> +
> + ret = usb_role_switch_set_role(con->usb_role_sw, u_role);
> + if (ret) {
> + dev_err(ucsi->dev, "con:%d: failed to set usb role:%d\n",
> + con->num, u_role);
> + ret = 0;
> + }
> +
> if (con->partner) {
> ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_SOP);
> if (ret) {
> diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
> index b7a92f246050..8474342b79a7 100644
> --- a/drivers/usb/typec/ucsi/ucsi.h
> +++ b/drivers/usb/typec/ucsi/ucsi.h
> @@ -8,6 +8,7 @@
> #include <linux/power_supply.h>
> #include <linux/types.h>
> #include <linux/usb/typec.h>
> +#include <linux/usb/role.h>
>
> /* -------------------------------------------------------------------------- */
>
> @@ -329,6 +330,8 @@ struct ucsi_connector {
> u32 rdo;
> u32 src_pdos[UCSI_MAX_PDOS];
> int num_pdos;
> +
> + struct usb_role_switch *usb_role_sw;
> };
>
> int ucsi_send_command(struct ucsi *ucsi, u64 command,
> --
> 2.24.0
thanks,
--
heikki
