On Thu, Aug 21, 2025 at 08:38:34PM +0000, RD Babiera wrote:
> Alt Mode drivers are responsible for sending Enter Mode through the TCPM,
> but only a DFP is allowed to send Enter Mode. typec_get_data_role gets
> the port's data role, which can then be used in altmode drivers via
> typec_altmode_get_data_role to know if Enter Mode should be sent.
The functions are okay by me, but is the above statement correct?
Are you mixing power role and data role?
> Signed-off-by: RD Babiera <rdbabiera@xxxxxxxxxx>
> ---
> drivers/usb/typec/class.c | 13 +++++++++++++
> include/linux/usb/typec.h | 1 +
> include/linux/usb/typec_altmode.h | 12 ++++++++++++
> 3 files changed, 26 insertions(+)
>
> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
> index 67a533e35150..9b2647cb199b 100644
> --- a/drivers/usb/typec/class.c
> +++ b/drivers/usb/typec/class.c
> @@ -2120,6 +2120,19 @@ void typec_set_data_role(struct typec_port *port, enum typec_data_role role)
> }
> EXPORT_SYMBOL_GPL(typec_set_data_role);
>
> +/**
> + * typec_get_data_role - Get port data role
> + * @port: The USB Type-C Port to query
> + *
> + * This routine is used by the altmode drivers to determine if the port is the
> + * DFP before issuing Enter Mode
> + */
> +enum typec_data_role typec_get_data_role(struct typec_port *port)
> +{
> + return port->data_role;
> +}
> +EXPORT_SYMBOL_GPL(typec_get_data_role);
> +
> /**
> * typec_set_pwr_role - Report power role change
> * @port: The USB Type-C Port where the role was changed
> diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
> index 252af3f77039..309251572e2e 100644
> --- a/include/linux/usb/typec.h
> +++ b/include/linux/usb/typec.h
> @@ -337,6 +337,7 @@ struct typec_plug *typec_register_plug(struct typec_cable *cable,
> void typec_unregister_plug(struct typec_plug *plug);
>
> void typec_set_data_role(struct typec_port *port, enum typec_data_role role);
> +enum typec_data_role typec_get_data_role(struct typec_port *port);
> void typec_set_pwr_role(struct typec_port *port, enum typec_role role);
> void typec_set_vconn_role(struct typec_port *port, enum typec_role role);
> void typec_set_pwr_opmode(struct typec_port *port, enum typec_pwr_opmode mode);
> diff --git a/include/linux/usb/typec_altmode.h b/include/linux/usb/typec_altmode.h
> index b3c0866ea70f..559cd6865ba1 100644
> --- a/include/linux/usb/typec_altmode.h
> +++ b/include/linux/usb/typec_altmode.h
> @@ -172,6 +172,18 @@ typec_altmode_get_svdm_version(struct typec_altmode *altmode)
> return typec_get_negotiated_svdm_version(typec_altmode2port(altmode));
> }
>
> +/**
> + * typec_altmode_get_data_role - Get port data role. Alt Mode drivers should only
> + * issue Enter Mode through the port if they are the DFP.
The second sentence should go below. But I'm not sure it's correct.
> + * @altmode Handle to the alternate mode
> + */
> +static inline enum typec_data_role
> +typec_altmode_get_data_role(struct typec_altmode *altmode)
> +{
> + return typec_get_data_role(typec_altmode2port(altmode));
> +}
> +
> /**
> * struct typec_altmode_driver - USB Type-C alternate mode device driver
> * @id_table: Null terminated array of SVIDs
> --
> 2.51.0.261.g7ce5a0a67e-goog
--
heikki
